text: <unk> s are a nonspecific symptom that are often defined as a rapid disagreeable sensation/pulsation that may be momentary or sustained and regular or irregular. It is one thing to understand the pathophysiology of<unk> s as a symptom and another to understand the pathophysiology of conditions that cause<unk> s.<unk> s are hypothesized to be due to neural-afferent sensory pathways located at both cardiac and extracardiac levels. It may be caused due to abnormal adjustments in the rate, rhythm and contractility of the heart.
option_0: Palpitation pathophysiology
option_1: Unstable angina pathophysiology
option_2: Heartburn pathophysiology
option_3: Orthopnea epidemiology and demographics
option_4: Syncope pathophysiology
option_5: Pacemaker syndrome pathophysiology
option_6: Chest pain risk factors
option_7: Diastolic dysfunction epidemiology and demographics