Supraventricular tachycardias

Abstract

Dr. Wagner: Thank you, Dr. Cooper. That was a superb and practical presentation of a subject of great interest. To summarize, briefly, our discussion today, it appears that supraventricular tachycardia may so alarm some of us that we ignore the caveat which tells us to look at the whole patient. These arrhythmias are not always due to heart disease. The primary disease generally deserves our first therapeutic efforts. We concentrated on five forms of supraventricular tachycardia, noting that sinus tachycardia is a response to problems outside the heart and should not be treated as an isolated entity. In life-threatening situations all other supraventricular tachycardias may be treated with electric shock. Under less pressing circumstances time should be taken to evaluate and treat other major problems and to identify the specific rhythm disorder. The arrhythmia will not always demand specific therapy. Atrial and junctional tachycardia are usually controlled by carotid sinus massage alone or combined with other methods of increasing vagal effect. These include increasing the blood pressure with phenylephrine, use of morphine, and use of digitalis. The treatment of choice for atrial flutter is low energy electric shock. Caution must be exercised in cases where the arrhythmia may be due to the effects of digitalis because, here, electric shock can produce a lethal, refractory, ventricular arrhythmia. Propranolol or atrial pacing are appropriate alternatives. Atrial fibrillation with rapid ventricular response is ideally treated with digitalis. There are certainly many other aspects of these rhythm problems that may challenge us in the emergency situation. We will reserve them for subsequent meetings.