What're the symptoms of cardiac arrhythmia?
The symptoms of cardiac arrhythmia are not specifically life-threatening, unless left untreated, Cardia arrhythmia can lead to more fatal forms of rhythm disturbance, eg/ premature ventricular depolarization may lead to ventricular fibrillation (resulting in a heart attack). The signs and symptoms of cardiac arrhythmias can range from completely asymptomatic to loss of consciousness or sudden cardiac death. In general, more severe symptoms are more likely to occur in the presence of structural heart disease. For example, sustained monomorphic VT, particularly in a normal heart, may be hemodynamically tolerated without syncope. In contrast, even non-sustained VT may be poorly tolerated and cause marked symptoms in
patients with severe LV dysfunction. Complaints such as lightheadedness, dizziness, quivering, shortness of breath, chest discomfort, heart fluttering or pounding, and forceful or painful extra beats are commonly reported with a variety of arrhythmias. Frequently patients notice their arrhythmia only after checking peripheral pulses. Certain symptoms raise the index of suspicion and can give clues to the type of arrhythmia. The presence of sustained regular palpitations or heart racing in young patients without any evidence of structural heart disease suggests the presence of an SVT due to atrioventricular nodal re-entry, or SVT due to an accessory pathway. Such tachycardias may frequently be accompanied by chest discomfort, diaphoresis, neck fullness, or a vasovagal type of response with syncope, diaphoresis, and nausea. It has been shown that the hemodynamic consequences of SVT and VT can have an autonomic basis, recruiting vasodepressor reflexes similar to that observed in neurocardiogenic syncope. Isolated or occasional premature beats suggest PACs or PVCs and are benign in the absence of structural heart disease.
Syncope in the setting of noxious stimuli such as pain, prolonged standing, and venepuncture, particularly when preceded by vagal-type symptoms (diaphoresis, nausea, vomiting), suggests neurocardiogenic (vasovagal) syncope. Occasionally, patients may report abrupt syncope without prodromal symptoms, suggesting the possibility of the "malignant" variety of neurocardiogenic syncope. Malignant neurocardiogenic syncope denotes syncope in the absence of a precipitating stimulus, with a short or absent prodrome, often resulting in injuries, and is associated with marked cardioinhibitory and bradycardic responses spontaneously or provoked by head-up tilt-table testing. The presence of sustained or paroxysmal sinus tachycardia, frequently associated with chronic fatigue syndrome and fibromyalgia, suggests the possibility of POTS (postural orthostatic tachycardia syndrome). This syndrome, which may be a form of autonomic dysfunction, is currently unexplained. It is characterized by a markedly exaggerated chronotropic response to head-up tilt-table testing and stress testing. POTS frequently has associated systemic signs such as muscle aches (fibromyalgia), cognitive dysfunction, and weight loss. Inappropriate sinus tachycardia syndrome is similar in presentation, but probably represents a separate disorder with alternative etiology, possibly due to atrial tachycardias in the sinus node area or dysregulation of sinus node automaticity.