Search

Echophonographic findings of three patients with spontaneous degeneration of porcine tricuspid and mitral valves presenting with musical murmurs are reported. Echocardiography in all these patients revealed systolic or diastolic cusp flutter similar in frequency to the musical murmur on simultaneously recorded phonocardiogram. Porcine tricuspid regurgitation is usually well tolerated and can be followed clinically for many years. However, patients with mitral porcine valves usually become symptomatic or present with congestive heart failure and usually require valve surgery soon after clinical or echo-phonocardiographic findings of valve regurgitation appear.

Direct involvement of the myocardium, a serious complication of sarcoidosis, was observed in 2 cases. The first patient had a progressively downhill course over 2 1 2 years, ending in sudden death. Her disease was characterized by recurrent ventricular arrhythmias, progressive heart failure and terminal arrhythmia. Cardiac catheterization and cineangiocardiograms performed before death revealed 2 ventricular aneurysms. Postmortem examination revealed extensive fibrosis and typical noncaseating granulomatous infiltration of the myocardium. The second patient presented with complete heart block. At the time of implantation of an epicardial pacemaker, biopsy of the myocardium and a mediastinal lymph node showed the noncaseating granulomas of sarcoidosis. In the subsequent years, atrioventricular (A-V) conduction improved and, when last seen, the patient maintained a normal sinus rhythm with first degree atrioventricular block.

The diagnostic difficulties between supraventricular tachyarrhythmias with intraventricular conduction delay and ventricular tachycardia have challenged the physician since the first recording of a ventricular tachycardia by Lewis in 1909. 2 The examples selected emphasize some of the diagnostic and therapeutic dilemmas of "broad QRS tachycardias" and their major differential features from abberrancy. Multiple simulataneous surface ECG leads are valuable in showing the direction of the initial activation forces of the QRS complexes, the frontal QRS axis and the configuration of the QRS in lead V 1 . Vagal maneuvers and intraatrial or esophageal leads are very useful in demonstrating the underlying atrial rhythm and atrioventricular dissociation when present. In life-threatening situations, urgent therapy or D.C. cardioversion may be required before a definitive diagnosis has been established. In recent years electrode catheter techniques for the diagnosis, 12,21,22 for arrhythmia induction and for the selection and assessment of the effectiveness of the antiarrhythmic drug therapy have been carried out in the management of recurrent broad QRS tachycardia. 23 In view of the inherent risks with the use of this invasive technique, it should be restricted to a carefully selected number of patients with recurrent life-threatening dysrhythmias as suggested by Scheinman. 24

Synchronized direct countershock, introduced by Lown et al 1 in 1962, is generally accepted as the treatment of choice for the rapid termination of atrial flutter. 2 In 1967, Haft and associates 3 first applied the technique of rapid atrial pacing in the treatment of atrial flutter, and its use was found to be safe even in patients with digitalis-excess. 4,5 Induction of atrial fibrillation has been initiated successfully with a variety of temporary pacemaker methods in the management of supraventricular tachycardias, 6 including atrial flutter. 7 On occasion, patients are encountered who, as a result of unresponsiveness to the intensive medical treatment 8 or intolerance to available antiarrhythmic drugs, continue to experience frequent bouts of atrial tachyarrhythmia. This is accompanied by markedly disabling and even lifethreatening symptoms making the application of other more definitive forms of therapy, such as the surgical induction of atrioventricular (AV) block and ventricular pacing