Persistent postoperative ventricular tachycardia treatment by using external cardiopulmonary support.

Drug-resistant incessant ventricular tachycardia (DRIVT) after cardiac surgery is a rare but almost always fatal event. Antiarrhythmic therapy seems to be ineffective and electrical cardioversion is of limited value when these patients present themselves with recurrent, sustained ventricular tachycardia. A patient with DRIVT in whom external cardiopulmonary support finally succeeded in bringing about resuscitation will be described in this article. The use of external cardiopulmonary support (CPS) should be considered in patients with this kind of malignant arrhythmia.

Triggered activity as a mechanism of recurrent ventricular tachycardia.

Triggered activity was shown to be the likely mechanism of recurrent tachycardia in a 28 year old Vietnamese man. During baseline electrophysiological testing the tachycardia was induced consistently by prolonged atrial or ventricular pacing but not by premature extrastimuli. Moreover, the tachycardia coupling intervals varied directly with the cycle length of the initiating drive. Procainamide and propranolol did not suppress tachycardia, but verapamil terminated it and prevented its reinitiation. The origin of the tachycardia was localised to the left ventricular inferoapical segment and four direct current countershocks of 200 J each delivered via an electrode catheter abolished the tachycardia. During 12 months of follow up the patient was not treated with antiarrhythmic agents and the tachycardia did not recur.

Life-threatening ventricular tachycardia and fibrillation induced by painless myocardial ischemia during exercise testing.

The clinical importance of myocardial ischemia without associated symptoms in patients with atherosclerotic coronary disease has not been clarified. We present three patients in whom painless cardiac ischemia was associated with the induction of cardiac arrest and/or ventricular tachycardia/fibrillation. In the two surviving patients, programmed ventricular stimulation did not induce ventricular arrhythmias. In one patient, successful coronary bypass surgery resulted in the elimination of exercise-induced painless myocardial ischemia and associated ventricular fibrillation; the other patient suffered a myocardial infarction after which ischemia and ventricular tachyarrhythmias could not be reproduced with exercise testing. We conclude that painless myocardial ischemia can cause life-threatening arrhythmias and is, therefore, a potentially lethal phenomenon.

Elevated CK-MB with normal total creatine kinase in suspected myocardial infarction: associated clinical findings and early prognosis.

To test the hypothesis that patients with normal serum levels of creatine kinase (CK) but elevated percentages of MB isoenzyme fractions in suspected myocardial infarction may have sustained clinically significant events, we studied the hospital course of 347 consecutive patients admitted with suspected myocardial infarction. Two hundred twenty-three patients had normal CK levels (182 +/- 44 IU) and normal MB percentages (normal group), 68 had elevated levels of both CK (1395 +/- 178 IU) and MB percentage (10.5 +/- 0.6) (macroinfarction group), and 40 had normal CK levels (96 +/- 7 IU) but elevated MB percentages (9.6 +/- 0.5) with typical enzyme curves (microinfarction group). Compared to the normal group, microinfarction patients were older, had more congestive heart failure, required more intensive monitoring and therapy during longer stays, and sustained a higher in-hospital mortality rate. Thus, these microinfarction patients are at increased risk and therefore warrant aggressive treatment and further evaluation.