Tachycardic

Tachycardic refers to having a heart rate that is higher than normal at rest. In adults, resting tachycardia is typically defined as a heart rate exceeding 100 beats per minute. The term can describe a person with tachycardia or a heart rhythm that is fast; in children, age-specific thresholds apply. Tachycardia can be sinus (originating from the sinoatrial node) or non-sinus, reflecting various tachyarrhythmias.

Causes are broadly categorized as physiological or pathological. Physiologic triggers include exercise, fever, anxiety, pain, dehydration, caffeine, or other stimulants. Pathologic causes include hypovolemia, anemia, hyperthyroidism, sepsis, heart failure, pulmonary embolism, myocardial ischemia, and arrhythmias. Some conditions produce a rapid heart rate as a compensatory mechanism (eg, hypotension or hypoxia).

Clinical presentation and evaluation: Many individuals with tachycardia are asymptomatic; others report palpitations, dizziness, lightheadedness, chest discomfort, or shortness of breath. Initial assessment should determine heart rate, rhythm, blood pressure, and perfusion. An electrocardiogram distinguishes sinus tachycardia from tachyarrhythmias such as atrial fibrillation, atrial flutter, supraventricular tachycardia, or ventricular tachycardia. Further testing may include laboratory studies (complete blood count, electrolytes, thyroid function), and imaging or echocardiography if cardiopulmonary disease is suspected.

Management: The approach targets the underlying cause and the patient’s stability. If tachycardia is causing instability, urgent rate or rhythm control is indicated. Treatments may include beta-blockers or calcium channel blockers for rate control, adenosine for certain SVTs, or electrical cardioversion for unstable rhythms. In chronic cases, addressing contributory factors and considering rhythm control or antiarrhythmic therapy may be appropriate.

Prognosis and notes: Tachycardia is a sign rather than a disease in itself. Persistent tachycardia can increase myocardial oxygen demand and reduce diastolic filling, and chronic rapid rates may contribute to tachycardiomyopathy if not managed. The outlook depends on the underlying cause and response to treatment.