Palpitations represent an intermittent or sustained awareness of the heartbeat, often described by the pt as a thumping, pounding, or fluttering sensation in the chest. The symptom may reflect a cardiac etiology, an extracardiac cause [hyperthyroidism, use of stimulants (e.g., caffeine, cocaine)], or a high catecholamine state (e.g., exercise, anxiety, pheochromocytoma). Contributory cardiac dysrhythmias include atrial or ventricular premature beats or, when sustained and regular, supraventricular or ventricular tachyarrhythmias (Chap. 132). Irregular sustained palpitations are often due to atrial fibrillation. Asking the pt to “tap out” the sense of palpitation can help distinguish regular from irregular rhythms.
APPROACH TO THE PATIENT Palpitations
Palpitations are often benign but may represent an important dysrhythmia if associated with hemodynamic compromise (lightheadedness, syncope, angina, dyspnea) or if found in pts with preexisting CAD, ventricular dysfunction, hypertrophic cardiomyopathy, aortic stenosis, or other valvular disease.
Helpful diagnostic studies include electrocardiography (if symptoms present at time of recording), exercise testing (if exertion typically precipitates the sense of palpitation or if underlying CAD is suspected), and echocardiography (if structural heart disease is suspected). If symptoms are episodic, ambulatory electrocardiographic monitoring can be diagnostic, including use of a Holter monitor (24–48 h of monitoring), event/loop monitor (for 2–4 weeks), or implantable loop monitor (for 1–2 years). Helpful laboratory studies may include testing for hypokalemia, hypomagnesemia, and/or hyperthyroidism.
For pts with benign atrial or ventricular premature beats in the absence of structural heart disease, therapeutic strategies include reduction of ethanol and caffeine intake, reassurance, and consideration of beta-blocker therapy for symptomatic suppression. Treatment of more serious dysrhythmias is presented in Chaps. 131 and 132.
For a more detailed discussion, see Loscalzo J: Palpitations, Chap. 37, p. 295, in HPIM-18.