ANATOMY

Detailed explanation-1: -Sinus tachycardia is an example of a supraventricular rhythm. In sinus tachycardia the sinus node fires between 100 and 180 beats per minute, faster than normal. The maximal heart rate decreases with age from around 200 bpm to 140 bpm.

Detailed explanation-2: -Tachycardia of atrial or ventricular origin reduces stroke volume and cardiac output, particularly when the ventricular rate is greater than 160 beats/min. The stroke volume becomes reduced because of decreased ventricular filling time and decreased ventricular filling (preload) at high rates of contraction.

Detailed explanation-3: -Tachycardia is an increased heart rate for any reason. It can be a usual rise in heart rate caused by exercise or a stress response (sinus tachycardia). Sinus tachycardia is considered a symptom, not a disease. Tachycardia can also be caused by an irregular heart rhythm (arrhythmia).

Detailed explanation-4: -Symptoms of pulmonary edema may include: Coughing up blood or bloody froth. Difficulty breathing when lying down (orthopnea) Feeling of “air hunger” or “drowning” (This feeling is called “paroxysmal nocturnal dyspnea” if it causes you to wake up 1 to 2 hours after falling asleep and struggle to catch your breath.)