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Evaluation of palpitations in adults

Evaluation of palpitations in adults
Author:
Peter J Zimetbaum, MD
Section Editor:
Mark D Aronson, MD
Deputy Editor:
Sara Swenson, MD
Literature review current through: Jan 2024.
This topic last updated: Nov 29, 2023.

INTRODUCTION — Palpitations are one of the most common symptoms of patients presenting to primary care providers and cardiologists [1]. Although the cause is usually benign, palpitations are occasionally a manifestation of a concerning or potentially life-threatening arrhythmia. Thus, a thoughtful and appropriate evaluation is needed for patients with palpitations, although many patients may not benefit from extensive testing.

The common etiologies for palpitations and a rational guide to the diagnostic evaluation of palpitations in adults are reviewed here. The approach to palpitations in children and the management of documented arrhythmias in children and adults are discussed separately. (See "Approach to the child with palpitations" and "Approach to the child with tachycardia" and "Arrhythmia management for the primary care clinician" and "Overview of the acute management of tachyarrhythmias" and "Premature ventricular complexes: Clinical presentation and diagnostic evaluation" and "Supraventricular premature beats".)

DEFINITION — Palpitations are a subjective symptom. They are defined as an unpleasant awareness of the forceful, rapid, or irregular beating of the heart. Patients may additionally describe the sensation as a rapid fluttering or a flip-flopping in the chest, or a pounding sensation in the chest or neck; the precise description of the subjective sensations experienced by the patient may help the clinician determine the cause of the palpitations [2].

ETIOLOGIES — The cause of palpitations can be determined in the majority of patients. The most common causes of palpitations include cardiac disorders, medical conditions including endocrine and metabolic abnormalities, psychiatric disorders, medication effects, and drug or other substance use effects (table 1). As an example, in a study of 190 consecutive patients presenting with a chief complaint of palpitations, an etiology was determined in 84 percent; among all patients, the cause was determined to be cardiac in 43 percent, psychiatric in 31 percent, miscellaneous (eg, medication induced, thyrotoxicosis, caffeine, cocaine, anemia, amphetamine, mastocytosis) in 10 percent, and unknown in the remaining 16 percent [3].

Cardiac disorders – Cardiac disorders are a common cause of palpitations, and this possibility generates the most concern among clinicians. Cardiac causes of palpitations include [4]:

Cardiac arrhythmias, including the development of a new arrhythmia or a significant change in the rate of a previously stable arrhythmia (such as atrial fibrillation). Cardiac arrhythmias may develop due to underlying structural heart disease (eg, cardiomyopathy, previous myocardial infarction) or identifiable conduction system abnormality (eg, long QT syndrome, Wolff-Parkinson-White syndrome, complete heart block), or they may be idiopathic. (See 'Personal and family history of cardiac disease' below.)

Arrhythmias causing palpitations include tachyarrhythmias, bradyarrhythmias, and ectopic beats.

Other less common cardiac causes include valvular heart disease (eg, mitral valve prolapse), pacemaker syndrome (ie, atrioventricular dyssynchrony due to single chamber [ventricular] pacing), atrial myxoma, and high-output cardiac states. (See "Modes of cardiac pacing: Nomenclature and selection", section on 'Pacemaker syndrome' and "Clinical manifestations, diagnosis, and management of high-output heart failure", section on 'Clinical manifestations' and "Mitral valve prolapse: Clinical manifestations and diagnosis", section on 'MVP syndrome'.)

In one study, features that predicted a cardiac etiology of palpitations included male sex, description of an irregular heartbeat, a personal history of heart disease, and event duration greater than five minutes [3].

The majority of patients with palpitations who undergo ambulatory monitoring are found to have supraventricular or ventricular ectopy or normal sinus rhythm [5-8]; normal sinus rhythm is correlated with symptomatic palpitations in up to 30 percent of patients.

Psychiatric disorders – Palpitations are a clinical feature of several psychiatric disorders, including panic attacks, generalized anxiety disorder, and somatization [9,10]. (See 'Coexisting psychiatric disorders' below.)

Other causes – Other important causes of palpitations are related to medication effects, drug or other substance effects, endocrine disorders, and metabolic abnormalities (table 1). (See 'Medications' below and 'Caffeine, nicotine, and other substance use' below and 'Coexisting medical conditions' below.)

OUR APPROACH — In the majority of patients with palpitations, we can determine the cause for their palpitations using a focused medical history, physical examination, 12-lead electrocardiogram (ECG), and limited laboratory testing [11,12]. In addition, most patients with a likely cardiac cause will need further evaluation with ambulatory cardiac rhythm monitoring to characterize the nature and severity of arrhythmia. For patients in whom no cause for the palpitations is immediately apparent after the initial evaluation, ambulatory cardiac rhythm monitoring is also performed to determine if a cardiac arrhythmia is responsible for their symptoms. (See 'Ambulatory cardiac rhythm monitoring' below.)

Patients experiencing palpitations at time of evaluation — We initially assess all patients to determine if they are currently experiencing palpitations at the time of the evaluation. If so, we immediately obtain a 12-lead ECG and perform a focused physical examination with specific attention to the cardiovascular system:

If an arrhythmia is confirmed by ECG, the patient's hemodynamic stability is assessed and the arrhythmia (and any underlying cause) managed as appropriate. (See "Arrhythmia management for the primary care clinician".)

In patients with no arrhythmia identified on the 12-lead ECG, we perform a cardiac examination. Some arrhythmias, particularly infrequent premature beats (eg, premature atrial complexes [PACs; also referred to as premature atrial beats, premature supraventricular complexes, or premature supraventricular beats] and premature ventricular complexes/contractions [PVCs; also referred to as premature ventricular beats or premature ventricular depolarizations]), are not captured due to the brief nature of the ECG but may be detected during several minutes of cardiac auscultation. (See "Supraventricular premature beats" and "Premature ventricular complexes: Clinical presentation and diagnostic evaluation".)

The diagnosis of PVCs or PACs is likely if the cardiac examination is consistent with premature contractions (see "Premature ventricular complexes: Clinical presentation and diagnostic evaluation", section on 'Physical examination' and "Supraventricular premature beats", section on 'Physical examination'), the patient describes the palpitations as an occasional "skipped beat" followed by a pause, and the palpitations do not occur during exercise (or resolve with exercise). In these patients, the ECG is examined for other abnormalities, and a medical history is taken to assess the characteristics of the palpitations and to evaluate for coexisting disease and other contributory factors. The evaluation and management of patients with PVCs and PACs is discussed in detail elsewhere. (See "Premature ventricular complexes: Clinical presentation and diagnostic evaluation" and "Supraventricular premature beats" and "Arrhythmia management for the primary care clinician".)

For patients in whom the initial ECG or physical examination does not provide a diagnosis, we proceed with the evaluation described below.

History — For patients who are not currently symptomatic, we elicit detailed characteristics of the palpitations from the patient and obtain a relevant clinical history including personal and family history of heart disease, medication and substance use, and a focused review of systems (eg, symptoms of hyperthyroidism or other endocrine disorders).

Palpitation characteristics — Several characteristics of the palpitations can be helpful in providing diagnostic clues to the etiology of the palpitations.

Age of onset – Although age does not appear to be an independent predictor of the presence or absence of a cardiac etiology of palpitations [3], the age at which palpitations begin may help narrow the differential diagnosis of likely causative arrhythmias.

Patients with episodes of rapid palpitations since childhood are likely to have a supraventricular tachycardia (SVT), probably an atrioventricular reentrant tachycardia (AVRT) with an accessory pathway or atrioventricular nodal reentrant tachycardia (AVNRT). (See "Narrow QRS complex tachycardias: Clinical manifestations, diagnosis, and evaluation" and "Atrioventricular reentrant tachycardia (AVRT) associated with an accessory pathway" and "Atrioventricular nodal reentrant tachycardia".)

Patients in whom palpitations have begun at an older age are more likely to have paroxysmal SVT (PSVT), atrial tachycardia, or atrial fibrillation (AF) or atrial flutter. (See "Narrow QRS complex tachycardias: Clinical manifestations, diagnosis, and evaluation" and "Focal atrial tachycardia" and "Multifocal atrial tachycardia" and "Atrial fibrillation: Overview and management of new-onset atrial fibrillation" and "Overview of atrial flutter".)

Older age of onset is also a risk factor for life-threatening ventricular arrhythmias, as these are more likely to occur in patients with structural heart disease. However, idiopathic ventricular tachycardia (VT) occasionally occurs in adolescence, and many cases of torsades de pointes due to congenital long QT syndrome occur before the age of 20. (See "Ventricular tachycardia in the absence of apparent structural heart disease" and "Congenital long QT syndrome: Epidemiology and clinical manifestations".)

Duration of palpitations – Palpitations that last for an "instant" (perhaps described as an occasional skipped beat) are more likely to represent PVCs or PACs; those that are sustained and last for minutes (or longer) are more consistent with supraventricular or ventricular arrhythmias. (See "Supraventricular premature beats" and "Premature ventricular complexes: Clinical presentation and diagnostic evaluation".)

Heart rate and rhythm regularity – Asking the patient to describe (or quantify if possible) the rate and degree of regularity of the palpitations may be helpful in identification of the cause. It may be helpful for the patient to tap out the rhythm with the fingers. Similarly, it may also be useful for the clinician to provide examples of rapid and regular rhythms, rapid and irregular rhythms, slow and regular rhythms, and slow and irregular rhythms. For example, a heart rate of >160 bpm is unlikely to be due to sinus tachycardia.

Rapid and regular rhythms are suggestive of PSVT or VT. (See "Narrow QRS complex tachycardias: Clinical manifestations, diagnosis, and evaluation", section on 'Paroxysmal and incessant SVT' and "Nonsustained ventricular tachycardia: Clinical manifestations, evaluation, and management".)

Rapid and irregular rhythms suggest paroxysmal AF, atrial flutter, or atrial tachycardia with variable block. (See "Paroxysmal atrial fibrillation" and "Overview of atrial flutter" and "Focal atrial tachycardia" and "Multifocal atrial tachycardia".)

Additional descriptive sensations – Other descriptions of the subjective sensations experienced by the patient can provide helpful information. As examples:

A feeling of rapid fluttering in the chest is typically seen in sustained ventricular or supraventricular arrhythmias, including sinus tachycardia. The regularity or irregularity of the palpitation may indicate the probable arrhythmic etiology; as examples, AF is irregular while sinus tachycardia and AVNRT are regular.

A sensation of "flip-flopping" in the chest, the experience of a pounding, or very strong heartbeat followed by the heart briefly "stopping" may be caused by premature supraventricular or ventricular beats. The sensation that the heart has stopped results from the pause following the premature contraction, and the pounding or flipping sensation results from the forceful contraction following the pause. (See "Supraventricular premature beats" and "Premature ventricular complexes: Clinical presentation and diagnostic evaluation".)

An irregular, pounding feeling in the neck may be experienced by patients with PVCs, complete heart block, pacemaker syndrome, or VT. It is caused by atrioventricular dissociation, with independent contraction of the atria and ventricles, resulting in occasional atrial contraction against a closed tricuspid and mitral valve. (See "Premature ventricular complexes: Clinical presentation and diagnostic evaluation" and "Third-degree (complete) atrioventricular block", section on 'Clinical presentation and evaluation' and "Modes of cardiac pacing: Nomenclature and selection", section on 'Pacemaker syndrome' and "Nonsustained ventricular tachycardia: Clinical manifestations, evaluation, and management", section on 'History and associated symptoms'.)

A sense of rapid and regular neck pulsations is typical of reentrant supraventricular arrhythmias, particularly AVNRT (or AVNRT due to a pre-excitation syndrome). AVNRT, the most common form of PSVT, is three times as common in women as in men [13]. In the typical form of AVNRT, the atria and ventricles are activated simultaneously at a rate of 160 to 180 beats per minute; as a result, the atria are always contracting against a closed or partially closed mitral and tricuspid valve. (See "Wolff-Parkinson-White syndrome: Anatomy, epidemiology, clinical manifestations, and diagnosis" and "Atrioventricular nodal reentrant tachycardia" and "Atrioventricular reentrant tachycardia (AVRT) associated with an accessory pathway".)

Associated presyncope or syncope – Lightheadedness, presyncope, or syncope may accompany palpitations and should prompt a search for a hemodynamically significant and potentially serious arrhythmia, most importantly VT. (See "Nonsustained ventricular tachycardia: Clinical manifestations, evaluation, and management", section on 'History and associated symptoms' and "Sustained monomorphic ventricular tachycardia: Clinical manifestations, diagnosis, and evaluation", section on 'History and associated symptoms'.)

Occasionally syncope is associated with SVT, particularly upon initiation of the episode. This type of syncope is believed to result from acute vasodilation, rapid heart rate with low cardiac output, or both [14,15]. Other tachyarrhythmias including AF and atrial flutter may cause palpitations and presyncope. (See "Syncope in adults: Epidemiology, pathogenesis, and etiologies", section on 'Cardiac arrhythmias' and "Atrial fibrillation: Overview and management of new-onset atrial fibrillation", section on 'History and physical examination' and "Overview of atrial flutter", section on 'History and physical examination'.)

Abruptness of palpitation onset and resolution – Palpitations that occur randomly and episodically and last for an instant are generally due to premature beats, while a gradual onset and resolution of palpitations suggests a sinus tachycardia. Palpitations described as abrupt in onset and termination may be caused by an SVT or VT. Of note, we find the abruptness of resolution to be more useful information, since many patients, even those with sinus tachycardia, do not appreciate the gradual onset of symptoms.

Patient self-termination of palpitations – Patients may report successful attempts at self-termination of their palpitations with carotid sinus massage or other vagal maneuvers, such as the Valsalva maneuver. This mode of termination is suggestive of SVTs, particularly AVNRT or AVRT with a bypass tract. (See "Atrioventricular nodal reentrant tachycardia" and "Atrioventricular reentrant tachycardia (AVRT) associated with an accessory pathway".)

Effect of positional changes – Some positional changes may precipitate arrhythmias, and in other cases, some positional changes may simply make palpitations more noticeable to the patient. As examples:

Among patients with AVNRT, the arrhythmia may be precipitated by standing up straight after bending over; the arrhythmia may then terminate when the patient becomes recumbent. (See "Atrioventricular nodal reentrant tachycardia", section on 'Triggers'.)

Patients may experience an intermittent heart pounding sensation while lying in bed, particularly while in the supine or left lateral decubitus position. This is commonly due to premature supraventricular or ventricular beats, which occur more frequently at slow heart rates. In addition, in the left lateral decubitus position, the apex of the heart is closer to the chest wall, which may account for the greater awareness of palpitations in this position. (See "Supraventricular premature beats" and "Premature ventricular complexes: Clinical presentation and diagnostic evaluation".)

Temporal association with exercise or emotional stress – A number of sustained SVTs and VTs may be provoked by sympathetic stimulation and catecholamine excess, as occurs during exercise or at times of stress. In studies involving exercise testing, nonsustained premature supraventricular and ventricular beats were more common than sustained arrhythmias, and the incidence of any arrhythmia is increased in patients with underlying heart disease. (See "Prognostic features of stress testing in patients with known or suspected coronary disease", section on 'Ventricular arrhythmias' and "Prognostic features of stress testing in patients with known or suspected coronary disease", section on 'Atrial arrhythmias'.)

On the other hand, idiopathic VT, especially when it arises from the right ventricular outflow tract, may occur during exercise in patients with structurally normal hearts; this arrhythmia most often presents during the second and third decades of life as palpitations, dizziness, or syncope [16]. (See "Ventricular tachycardia in the absence of apparent structural heart disease".)

SVTs, including AF, can be induced during exercise or at the termination of exercise when withdrawal of catecholamines is coupled with a surge in vagal tone [17]. AF occurring during this relative increase in vagal tone is particularly common in athletic men in the third to sixth decade of life [18]. (See "Paroxysmal atrial fibrillation", section on 'Autonomic nervous system'.)

Arrhythmias may also occur during emotionally startling experiences. As an example, patients with the long QT syndrome, especially congenital type 1 or 2 (an inherited abnormality of myocardial repolarization), characteristically present with palpitations during periods of vigorous exercise or emotional stress; polymorphic VT (known as torsades de pointes) is the classic arrhythmia seen [19]. (See "Congenital long QT syndrome: Epidemiology and clinical manifestations".)

Inappropriate sinus tachycardia is a rare disorder that manifests as palpitations during periods of minimal physical exertion or with emotional stress. This arrhythmia is characterized by an inappropriate increase in the sinus rate and is most frequently seen in young women; it may result from a hypersensitivity to beta-adrenergic stimulation. (See "Sinus tachycardia: Evaluation and management", section on 'Inappropriate sinus tachycardia'.)

Additional clinical history — In addition to collecting information regarding the details of the palpitations and any associated symptoms, the patient's personal and family history of heart disease, coexisting medical and psychiatric disease, medications and other substances used, and a focused review of symptoms may help narrow the diagnostic possibilities.

Personal and family history of cardiac disease — We inquire about a personal or family history of heart disease, including mitral valve prolapse, structural heart disease (including cardiomyopathy), myocardial infarction, and other cardiac disorders, including prolonged QT syndrome, Wolff-Parkinson-White syndrome, pacemaker device, or sudden cardiac death.

Mitral valve prolapse – Virtually every type of supraventricular arrhythmia, as well as premature ventricular depolarizations and nonsustained VT, have been described with mitral valve prolapse, and palpitations are nearly ubiquitous in the subset of patients with mitral valve prolapse who have the mitral valve prolapse syndrome, even in patients who do not have an identifiable arrhythmia [20]. (See "Mitral valve prolapse: Overview of complications and their management" and "Mitral valve prolapse: Clinical manifestations and diagnosis", section on 'MVP syndrome'.)

Structural heart disease – A personal or family history of structural heart disease (including cardiomyopathy or myocardial infarction) is associated with many arrhythmias but in particular raises the level of concern for life-threatening ventricular arrhythmias. (See "Ventricular arrhythmias: Overview in patients with heart failure and cardiomyopathy", section on 'Underlying structural myocardial disease' and "Ventricular arrhythmias: Overview in patients with heart failure and cardiomyopathy", section on 'Myocardial ischemia' and "Ventricular arrhythmias: Overview in patients with heart failure and cardiomyopathy", section on 'Mechanical factors' and "Hypertrophic cardiomyopathy: Clinical manifestations, diagnosis, and evaluation", section on 'Arrhythmias'.)

Personal or family history of cardiac conduction system disease – We inquire about a personal or family history of cardiac conduction system disease, such as Wolff-Parkinson-White syndrome or congenital (genetic) prolonged QT syndrome. Wolff-Parkinson-White syndrome increases the likelihood of a variety of SVTs (which may degenerate into life-threatening VF); prolonged QT syndrome is associated with polymorphic VT (torsades de pointes). (See "Wolff-Parkinson-White syndrome: Anatomy, epidemiology, clinical manifestations, and diagnosis", section on 'Familial WPW' and "Wolff-Parkinson-White syndrome: Anatomy, epidemiology, clinical manifestations, and diagnosis", section on 'Arrhythmias associated with WPW' and "Congenital long QT syndrome: Epidemiology and clinical manifestations", section on 'Types of arrhythmias'.)

In patients with known atrial fibrillation and a "controlled" heart rate, palpitations may represent episodes of poorly controlled ventricular response due to increase AV nodal conduction in the setting increased sympathetic stimulation. (See "Atrial fibrillation: Overview and management of new-onset atrial fibrillation".)

A family history of sudden cardiac death is not diagnostic of a familial arrhythmogenic cardiac disorder but does alert the clinician to the possibility that one may be present. (See "Approach to sudden cardiac arrest in the absence of apparent structural heart disease", section on 'Familial SCD' and "Cardiac evaluation of the survivor of sudden cardiac arrest", section on 'Evaluation of family members'.)

The presence of a pacemaker, particularly a device with single chamber (ventricular) pacing, raises the possibility of pacemaker syndrome (atrioventricular dyssynchrony). (See "Modes of cardiac pacing: Nomenclature and selection", section on 'Pacemaker syndrome'.)

Coexisting medical conditions — We evaluate patients for a history of (or symptoms consistent with) any of the medical conditions that may be associated with palpitations (eg, high-output cardiac states, metabolic and endocrine causes, and chronic obstructive pulmonary disease [COPD]) (table 1).

High-output cardiac state – Palpitations due to increased cardiac contractility and tachyarrhythmias (sinus tachycardia and others) may occur in conditions associated with a high output cardiac state, such as Paget disease of bone, fever, anemia, pregnancy, hyperthyroidism, and vascular shunts (intra- or extra-cardiac). (See "Causes and pathophysiology of high-output heart failure", section on 'Causes and their mechanisms'.)

Pregnancy related – In addition to palpitations related to the high-output state associated with pregnancy, peripartum cardiomyopathy may be associated with arrhythmias, particularly AF and ventricular arrhythmias. (See "Supraventricular arrhythmias during pregnancy" and "Peripartum cardiomyopathy: Treatment and prognosis", section on 'Arrhythmia'.)

Metabolic and endocrine causes – Several metabolic and endocrine disorders are associated with palpitations.

Hypoglycemia (related to diabetes treatment, insulinoma, or another cause) may cause palpitations in addition to other symptoms, including tremor, diaphoresis, weakness, confusion. The palpitations are typically due to sinus tachycardia secondary to catecholamine excess. (See "Hypoglycemia in adults without diabetes mellitus: Clinical manifestations, causes, and diagnosis", section on 'Symptoms' and "Hypoglycemia in adults with diabetes mellitus", section on 'Symptoms'.)

Hyperthyroidism, characterized by sweating, unintentional weight loss, tremors, and heat intolerance, may cause palpitations due to sinus tachycardia or AF. (See "Overview of the clinical manifestations of hyperthyroidism in adults", section on 'Cardiovascular'.)

Patients with pheochromocytoma may experience episodic palpitations in addition to sweating, tremor, headache and dyspnea, all symptoms of catecholamine excess. (See "Clinical presentation and diagnosis of pheochromocytoma", section on 'Symptoms and signs'.)

Chronic obstructive pulmonary disease – Palpitations may occur in patients with COPD due to the relatively high frequency of arrhythmias that occur among these patients. Commonly seen arrhythmias include multifocal atrial tachycardia (MAT), AF, and ventricular arrhythmias; the prevalence of arrhythmias is likely related to the severity of lung disease. (See "Arrhythmias in COPD", section on 'Specific arrhythmias associated with COPD'.)

Coexisting psychiatric disorders — All patients should be evaluated for a coexisting psychiatric disorder that may be associated with palpitations, including generalized anxiety disorder, panic disorder, and somatization (table 1). Patients with anxiety or panic disorder may find it difficult, however, to discern whether the feeling of anxiety or panic preceded or resulted from the palpitations. Palpitations associated with psychiatric conditions are not necessarily associated with an objective arrhythmia. In addition, psychiatric illness may coexist with a nonpsychiatric (cardiac or other) cause of palpitations [3,21,22]. (See "Panic disorder in adults: Epidemiology, clinical manifestations, and diagnosis" and "Generalized anxiety disorder in adults: Epidemiology, pathogenesis, clinical manifestations, course, assessment, and diagnosis" and "Somatic symptom disorder: Epidemiology and clinical presentation", section on 'Clinical presentation'.)

Medications — A history of all medications, including over-the-counter medications, should be obtained. In particular, palpitations due to SVTs occur with the use of sympathomimetic agents, vasodilators, anticholinergic drugs, or during withdrawal from beta blockers.

Caffeine, nicotine, and other substance use — Consumption of caffeine, nicotine-containing products, and other drugs (eg, alcohol, cocaine or amphetamines) should be established. If used, any temporal relationship between the use of these products and the occurrence of palpitations should be sought.

Typical caffeine consumption does not seem to increase the risk of arrhythmias, although excessive use in sensitive individuals may increase this risk. Cocaine may induce supraventricular and ventricular arrhythmias, and amphetamines may cause SVTs. Cigarette smoking or the use of nicotine replacement products such as nicotine lozenges may cause palpitations. (See "Cardiovascular effects of caffeine and caffeinated beverages", section on 'Other arrhythmias' and "Clinical manifestations, diagnosis, and management of the cardiovascular complications of cocaine abuse", section on 'Arrhythmias and conduction abnormalities' and "Methamphetamine: Acute intoxication", section on 'Tachycardia' and "Pharmacotherapy for smoking cessation in adults", section on 'Nicotine replacement therapy' and "Epidemiology, risk factors, and prevention of atrial fibrillation" and "Epidemiology, risk factors, and prevention of atrial fibrillation", section on 'Alcohol'.)

Focused physical examination — Although the clinician rarely has the opportunity to examine a patient during an episode of palpitations, the physical examination is often useful in defining potential abnormalities that may provide an indication of the etiology of the palpitations. The following physical examination findings, when present, may provide useful clues as to the etiology of the patient's palpitations.

We check temperature, blood pressure, pulse, oxygen saturation, and respiratory rate.

Elevated temperature raises the possibility of infection, malignancy, and even intracardiac myxoma. An increased heart rate is a normal physiologic response in the setting of a fever.

Elevated blood pressure and pulse may be consistent with pheochromocytoma, substance use, beta blocker withdrawal, or another condition associated with catecholamine excess. (See 'Coexisting medical conditions' above and 'Caffeine, nicotine, and other substance use' above and 'Medications' above.)

In addition to checking vital signs, we perform a careful cardiovascular examination, with attention to the following:

A midsystolic click (and possibly a late systolic murmur) which are associated with mitral valve prolapse. (See 'Personal and family history of cardiac disease' above and "Mitral valve prolapse: Clinical manifestations and diagnosis".)

A harsh holosystolic murmur heard along the left sternal border that increases with the Valsalva maneuver suggests hypertrophic obstructive cardiomyopathy. (See 'Personal and family history of cardiac disease' above.)

A diastolic tumor "plop" may be heard with the classic left atrial myxoma. In addition, signs of systemic embolization may be evident. (See 'Personal and family history of cardiac disease' above and "Cardiac tumors".)

Clinical evidence of a dilated cardiomyopathy and heart failure: Other than a diffuse and laterally displaced point of maximal impulse, well-compensated dilated cardiomyopathy may be difficult to discern on physical examination. Conversely, patients with dilated cardiomyopathy complicated by heart failure typically demonstrate evidence of volume overload (pulmonary congestion, peripheral edema, and elevated jugular venous pressure) and additionally may have an audible S3 gallop. (See 'Personal and family history of cardiac disease' above.)

In patients with AF, a cardiac examination after ambulation can be very useful for evaluating palpitations. Although palpitations may not be present at rest when the ventricular response is slow, a brisk walk may unmask a poorly controlled ventricular response to even minimal exertion. (See 'Personal and family history of cardiac disease' above.)

A pulmonary examination can provide important clinical information in a patient with palpitations:

We assess for COPD (eg, prolonged expiratory phase of respiration, wheezing, lung hyperinflation, decreased breath sounds). (See "Chronic obstructive pulmonary disease: Diagnosis and staging", section on 'Physical examination' and 'Coexisting medical conditions' above.)

We also evaluate for signs of endocrine abnormalities, particularly hyperthyroidism:

Signs of hyperthyroidism include sweating, fine tremor, exophthalmos, thyromegaly and brisk deep tendon reflexes. (See 'Coexisting medical conditions' above and "Diagnosis of hyperthyroidism", section on 'Physical examination'.)

12-lead ECG — For all patients with palpitations, a 12-lead ECG is required as part of the initial evaluation.

If an arrhythmia is documented on ECG, the arrhythmia should be managed as indicated. (See "Arrhythmia management for the primary care clinician".)

Although the majority of patients are in sinus rhythm when the initial ECG is obtained, it may still help narrow the differential diagnosis of palpitations [13]. Specifically, the ECG should be examined for the following findings:

A short PR interval and delta waves (Wolff-Parkinson-White syndrome), consistent with ventricular preexcitation; this suggests the likelihood SVT (waveform 1).

Marked left ventricular hypertrophy with deep septal Q waves in I, aVL, and V4 through V6 suggest the presence of hypertrophic obstructive cardiomyopathy. Left ventricular hypertrophy with evidence of left atrial abnormality (as indicated by a terminal P wave force in V1 more negative than 0.04 msec and notched in lead II) suggests a likely substrate for AF. (See "Hypertrophic cardiomyopathy: Clinical manifestations, diagnosis, and evaluation".)

The presence of Q waves characteristic of a prior myocardial infarction suggests the possibility of nonsustained or sustained VT. (See "Pathogenesis and diagnosis of Q waves on the electrocardiogram" and "Ventricular arrhythmias during acute myocardial infarction: Incidence, mechanisms, and clinical features", section on 'Late arrhythmias'.)

Isolated supraventricular and/or ventricular ectopy may occasionally be seen on the 12-lead ECG. In particular, the morphology of the PVCs, particularly in patients without heart disease, can indicate the risk of serious consequences (eg, development of life-threatening arrhythmias or cardiomyopathy). (See "Premature ventricular complexes: Treatment and prognosis", section on 'Premature ventricular complex characteristics'.)

Prolongation of the QT interval and abnormal T wave morphology may suggest the presence of the long QT syndrome (waveform 2). (See "Congenital long QT syndrome: Epidemiology and clinical manifestations".)

Bradycardia of any etiology can be accompanied by premature ventricular depolarizations and associated palpitations. In particular, complete heart block can be associated with premature ventricular depolarizations or a prolonged QT interval and torsades de pointes.

Limited laboratory testing — There are no evidence-based guidelines to direct the laboratory workup of patients with palpitations. In most patients, we perform limited laboratory testing to rule out anemia and hyperthyroidism. In addition, we test for specific metabolic disorders as suggested by the history and physical examination. Finally, toxicology testing may be indicated in patients for whom substance use is suspected.

Additional testing for select patients

Echocardiography for any patient with possible structural heart disease — We obtain an echocardiogram in patients whose history, physical examination, or ECG raise concern for structural heart disease. These include those with a family history, symptoms, or ECG concerning for hypertrophic cardiomyopathy; who have a murmur on physical examination; or who have an ECG with Q waves suggesting prior myocardial infarction, a left bundle branch block, or changes consistent with ventricular hypertrophy. (See "Hypertrophic cardiomyopathy: Clinical manifestations, diagnosis, and evaluation", section on 'Electrocardiography' and "Left bundle branch block", section on 'ECG findings and diagnosis' and "Left ventricular hypertrophy: Clinical findings and ECG diagnosis", section on 'Electrocardiographic findings: General'.)

Ambulatory cardiac rhythm monitoring — Ambulatory ECG monitoring (including the 24- to 48-hour Holter monitor, the two- to four-week event monitor, and the insertable cardiac monitor [ICM; also sometimes referred to as implantable cardiac monitor or implantable loop recorder]) is the most important tool for the diagnosis of unexplained palpitations [11,23]. (See "Ambulatory ECG monitoring".)

Indications — We use the clinical history gathered from the patient, along with the results of the physical examination, the 12-lead ECG, and the echocardiography (if appropriate) to determine the need for further evaluation including ambulatory cardiac rhythm monitoring.

Low risk for concerning arrhythmias – For patients at low risk of concerning arrhythmias (eg, those whose palpitations are unsustained and well tolerated and who do not have evidence of heart disease by history, physical examination, or 12-lead ECG), we generally do not obtain ambulatory rhythm monitoring. If a patient is very concerned about their symptoms and requires reassurance, however, we will perform two weeks of event monitoring.

Regardless of whether ambulatory rhythm monitoring is performed, we educate the patient and ask them to alert us for any increase in the pattern or severity of their symptoms. (See 'Management' below.)

High risk for concerning arrhythmias – We obtain ambulatory cardiac rhythm monitoring for all patients whose initial diagnostic evaluation suggests the possibility of a disorder known to be associated with the development of VT [24]:

Palpitations that are sustained, poorly tolerated, or associated with syncope or presyncope

Organic heart disease (eg, scar formation from myocardial infarction, dilated cardiomyopathy of any cause, clinically significant valvular heart disease, hypertrophic cardiomyopathy)

A personal or family history of arrhythmia, syncope, sudden death, cardiomyopathy, or long QT syndrome

An inpatient evaluation may be more appropriate for those patients with frequent symptoms and associated syncope.

Methods — There are three methods of ambulatory cardiac rhythm monitoring, a 24- or 48-hour continuous Holter monitor, a two- to four-week continuous loop event recording, and an implantable continuous loop even recorder which can be kept in place for up to two years. In the majority of patients with palpitations, we prefer two weeks of continuous loop event recording as the method of ambulatory monitoring.

The Holter monitor is a 24- or 48-hour monitoring system that records and saves data continuously. The device is worn for one or two days while the patient keeps a diary recording the time and characteristics of symptoms.

Holter monitors are limited by the short duration of time available for monitoring. In addition, arrhythmias may be identified that are unrelated to the palpitations. This was illustrated in a study of over 1400 older adult patients aged 60 to 94 years, 8.3 percent of whom complained of palpitations [25]. Arrhythmias, predominantly conduction abnormalities and sinus bradycardia, were found in 12.6 percent. However, the prevalence of palpitations was similar in those with and without documented arrhythmias. In another study of 518 patients who underwent 24-hour ambulatory rhythm monitoring, 34 percent experienced typical palpitations, but the corresponding cardiac rhythm was normal [8]. (See "Ambulatory ECG monitoring" and "Ambulatory ECG monitoring", section on 'When to choose continuous ECG (Holter) monitoring'.)

Continuous loop event recorders continuously record data but typically save the data for the preceding and subsequent two minutes (or for other time periods as programmed), but only when the patient manually activates the monitor. These recording devices are capable of direct transmission of the ECG as an audio signal via the telephone [26]. Continuous loop recorders can be used for longer periods than Holter monitors; since most patients with palpitations do not have them daily, this method is more likely to record data during palpitations. Furthermore, with event recorders, symptoms can be directly correlated with the cardiac rhythm since the patient activates the monitor. (See "Ambulatory ECG monitoring", section on 'Event (loop) monitor'.)

The ICM is a subcutaneous monitoring device for the detection of cardiac arrhythmias [27]. Such a device is typically implanted in the left pectoral region and stores events when the device is activated automatically according to programmed criteria or manually with magnet application. The ICM is most often used for patients with unexplained syncope, but it may have a role for those in whom other methods have failed to document the cause of palpitations. (See "Ambulatory ECG monitoring", section on 'Insertable cardiac monitor'.)

Continuous loop devices have a higher diagnostic yield than Holter monitors (66 to 83 percent versus 33 to 35 percent), and are likely more cost effective [5,28,29]. A Holter monitor, however, can be useful in patients with frequent, daily palpitations, particularly if the patient is likely to have trouble activating the loop recorder.

Regardless of the method, two weeks of event monitoring is sufficient to make a diagnosis in the vast majority of patients with palpitations and is less costly than the standard monitoring period of one month. As an example, in a retrospective analysis of 5000 patients who had undergone event recording with a continuous loop monitor, 87 percent had an initial transmission corresponding to palpitations in the first two weeks of monitoring [30]. An additional 9 percent of initial transmissions occurred by four weeks of monitoring. In a second report of 105 outpatients with palpitations referred for event monitoring, the diagnostic yield was 1.04 diagnoses per patient in week 1, 0.15 in week 2, and 0.01 diagnoses per patient in week 3 and beyond [6]. The cost-effectiveness ratio increased from USD $98 per new diagnosis in week one, to $576 and $5832 in weeks 2 and 3, respectively.

An implantable event recorder can be used in selected patients with extremely infrequent but symptomatic palpitations (eg, typically those associated with presyncope or syncope).

Referral for electrophysiologic testing — If palpitations are sustained or poorly tolerated, an electrophysiologic (EP) study may be indicated [31]. Invasive cardiac EP evaluation can be used for the diagnosis of a suspected arrhythmia when ambulatory rhythm monitoring has not provided a diagnosis and in patients with a high pretest likelihood of a serious arrhythmia (eg, patients with structural heart disease). (See "Invasive diagnostic cardiac electrophysiology studies".)

MANAGEMENT — Management of patients with palpitations depends upon the suspected or identified cause.

For patients in whom the initial evaluation suggests a likely medical or medication-related cause as the etiology of their palpitations, we proceed with an intervention as appropriate. As examples:

If hypoglycemia is suspected as the cause, we ask patients to check a simultaneous capillary blood glucose at the time of palpitations. If hypoglycemia is documented, and palpitations resolve with correction of hypoglycemia (in the absence of other risk factors for arrhythmias), no further evaluation may be necessary. (See "Hypoglycemia in adults with diabetes mellitus", section on 'Symptoms' and "Hypoglycemia in adults with diabetes mellitus", section on 'Strategies to manage hypoglycemia'.)

If palpitations begin in temporal association with initiation of a medication known to cause palpitations (eg, methylphenidate, dextroamphetamine) or upon abrupt discontinuation of a beta blocker, we discontinue the new medication or resume the beta blocker (if safe and appropriate to do so). If palpitations resolve, and there are no other risk factors for arrhythmias, then no further evaluation may be necessary. (See "Attention deficit hyperactivity disorder in adults: Treatment overview", section on 'Choosing a stimulant' and "Tapering and discontinuing antihypertensive medications", section on 'Withdrawal syndromes'.)

For patients with palpitations associated with a documented arrhythmia, the arrhythmia is managed as appropriate. (See "Arrhythmia management for the primary care clinician".)

For patients with palpitations that have no cause identified despite extensive evaluation, the role of anxiety or panic disorder should be explored. If appropriate, the underlying psychiatric condition should be treated or the patient referred to a behavioral medicine provider for further evaluation and management. (See "Generalized anxiety disorder in adults: Management" and "Management of panic disorder with or without agoraphobia in adults".)

In addition, we advise these patients to monitor for any increase in frequency or severity of palpitations, or the development of any associated symptoms. If these develop, a repeat evaluation including ambulatory cardiac rhythm monitoring may be needed.

For those patients with palpitations that are associated with documented sinus rhythm on ambulatory rhythm monitoring and with an otherwise normal evaluation, we offer reassurance as to the benign nature of their symptoms. We do, however, ask them to monitor their palpitations for an increase in frequency, severity or development of any associated symptoms, as these may be indications for repeat or further evaluation.

SUMMARY AND RECOMMENDATIONS

Definition – Palpitations are defined as an unpleasant awareness of the forceful, rapid, or irregular beating of the heart. Patients may additionally describe the sensation as a rapid fluttering or a flip-flopping in the chest, or a pounding sensation in the chest or neck; the precise description of the subjective sensations experienced by the patient may help the clinician determine the cause of the palpitations. (See 'Definition' above.)

Etiologies – Common etiologies are displayed in the table (table 1). (See 'Etiologies' above.)

Common cardiac causes include the development of a new arrhythmia or a significant change in the rate of a previously stable arrhythmia. Less common cardiac causes include mitral valve prolapse, pacemaker syndrome, atrial myxoma, and high-output cardiac states.

Palpitations are also a clinical feature of several psychiatric disorders, including panic attacks, generalized anxiety disorder, and somatization.

Other important causes of palpitations are related to medication effects, drug or other substance effects, endocrine disorders, and metabolic abnormalities.

Approach to diagnosis – In the majority of patients with palpitations, the cause for their palpitations can be determined using a focused medical history, physical examination, 12-lead electrocardiogram (ECG), and limited laboratory testing. (See 'Our approach' above.)

Patients symptomatic on presentation – We initially assess all patients to determine if they are currently experiencing palpitations at the time of the evaluation. If so, we immediately obtain a 12-lead ECG and perform a focused physical examination with specific attention to the cardiovascular system (see 'Patients experiencing palpitations at time of evaluation' above):

-If an arrhythmia is confirmed by ECG, the patient's hemodynamic stability is assessed and the arrhythmia (and any underlying cause) managed as appropriate.

-In patients with no arrhythmia identified on the 12-lead ECG, we perform a cardiac examination. Some arrhythmias, particularly infrequent premature ventricular complexes (PVCs) or premature atrial complexes (PACs), are not captured due to the brief nature of the ECG but may be detected during several minutes of cardiac auscultation.

Patients without symptoms on presentation – For patients who are not currently symptomatic, we elicit detailed characteristics of the palpitations from the patient and obtain a relevant clinical history, including personal and family history of heart disease, medication and substance use, and a focused review of systems (eg, symptoms of hyperthyroidism or other endocrine disorders). (See 'History' above.)

Focused physical examination – Although the clinician rarely has the opportunity to examine a patient during an episode of palpitations, the physical examination is often useful in defining potential abnormalities that may provide an indication of the etiology of the palpitations. We check temperature, blood pressure, pulse and respiratory rate, and perform a careful cardiovascular examination. A pulmonary examination can provide important clinical information, and we also evaluate for signs of endocrine abnormalities. (See 'Focused physical examination' above.)

ECG for all patients – For all patients with palpitations, a 12-lead ECG is required as part of the initial evaluation. Although the majority of patients are in sinus rhythm when the initial ECG is obtained, it may still help narrow the differential diagnosis of palpitations. Specifically, the ECG should be examined for findings suggestive of underlying structural heart disease or electrical system disturbance. (See '12-lead ECG' above.)

Limited laboratory testing – There are no evidence-based guidelines to direct the laboratory workup of patients with palpitations. In most patients, we perform limited laboratory testing to rule out anemia and hyperthyroidism. In addition, we test for specific metabolic disorders as suggested by the history and physical examination. Finally, toxicology testing may be indicated in patients for whom substance use is suspected. (See 'Limited laboratory testing' above.)

Echocardiography for some patients – We obtain an echocardiogram in patients whose history, physical examination, or ECG raise concern for structural heart disease. These include those with a family history, symptoms, or ECG concerning for hypertrophic cardiomyopathy, who have a murmur on physical examination, or who have an ECG with Q waves suggesting prior myocardial infarction, a left bundle branch block, or changes consistent with ventricular hypertrophy. (See 'Echocardiography for any patient with possible structural heart disease' above.)

Need for ambulatory monitoring – We use the clinical history gathered from the patient, along with the results of the physical examination, the 12-lead ECG, and the echocardiography (if appropriate) to determine the need for further evaluation including ambulatory cardiac rhythm monitoring. (See 'Ambulatory cardiac rhythm monitoring' above.)

For patients who are at low risk of concerning arrhythmias (eg, those whose palpitations are unsustained and well tolerated and who do not have evidence of heart disease by history, physical examination, or 12-lead ECG), we generally do not obtain ambulatory rhythm monitoring. If a patient is very concerned about their symptoms and requires reassurance, however, we will perform two weeks of event monitoring.

We obtain ambulatory cardiac rhythm monitoring for all patients whose initial diagnostic evaluation suggests the possibility of a disorder known to be associated with the development of ventricular tachycardia (VT):

-Palpitations that are sustained, poorly tolerated, or associated with syncope or presyncope

-Organic heart disease (eg, scar formation from myocardial infarction, dilated cardiomyopathy of any cause, clinically significant valvular heart disease, hypertrophic cardiomyopathy)

-A personal or family history of arrhythmia, syncope, sudden death, cardiomyopathy, or long QT syndrome.

An inpatient evaluation may be more appropriate for those patients with frequent symptoms and associated syncope.

Referral for electrophysiologic testing – If palpitations are sustained or poorly tolerated, an electrophysiologic (EP) study may be indicated. Invasive cardiac EP evaluation can be used for the diagnosis of a suspected arrhythmia when ambulatory rhythm monitoring has not provided a diagnosis and in patients with a high pretest likelihood of a serious arrhythmia (eg, patients with structural heart disease). (See 'Referral for electrophysiologic testing' above.)

Management – Management of patients with palpitations depends upon the suspected or identified cause. (See 'Management' above.)

For patients in whom the initial evaluation suggests a likely medical cause as the etiology of their palpitations, we proceed with treatment or intervention as appropriate.

For patients with palpitations that have no cause identified, the role of anxiety or panic disorder should be explored. If appropriate, the underlying psychiatric condition should be treated or the patient referred to a behavioral medicine provider for further evaluation and management.

For those patients with palpitations that are associated with documented sinus rhythm on ambulatory rhythm monitoring and with an otherwise normal evaluation, we offer reassurance as to the benign nature of their symptoms. We do, however, ask them to monitor their palpitations for an increase in frequency, severity or development of any associated symptoms, as these may be indications for repeat or further evaluation.

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Topic 6835 Version 41.0

References

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