Use of cardiac troponin T rapid assay in the diagnosis of a myocardial injury secondary to electrical cardioversion.

BACKGROUND AND HYPOTHESIS: This study was carried out to determine whether cardiac troponin T test in rapid assay gives positive results in patients previously submitted to cardioversion or electrical defibrillation. METHODS: Forty patients with supraventricular tachyarrhythmias lasting no more than 2 days were treated with electrical cardioversion. The total creatine phosphokinase (CPK)-MB isoenzyme and troponin T in rapid assay were measured at baseline and at 6, 12, and 24 h thereafter. RESULTS: Total CPK baseline levels were normal in all cases; within 4 h, the serum CPK levels increased by 98%, at 6 h by 111.5%, at 12 h by 168%, and at 24 h by 225% (p > 0.01). The CPK-MB isoenzyme showed no percentage increase of total CPK higher than 5%, measured at 6, 12, and 24 h after the shock, independent of the number of attempts of cardioversion. The troponin T test was also negative in all cases at baseline and at 6, 12, and 24 h after cardioversion. CONCLUSION: We conclude that the absence of elevations in CPK-MB levels and cardiac troponin T levels matched clinical and electrocardiographic results showing absence of myocardial damage after electrical cardioversion.

[Evaluation of the anti-arrhythmia effect of intravenous flecainide in supraventricular tachyarrhythmias]. / Valoración antiarrítmica de la flecainida endovenosa en las taquiarritmias supraventriculares.

We studied the effects of intravenous flecainide acetate, given as a single dose of 2 mg/kg in no less than 15 minutes, on 31 patients with supraventricular tachyarrhythmias. Fourteen (87%) of the 16 patients with paroxysmal atrial fibrillation converted to sinus node rhythm. All 7 (100%) of the patients with paroxysmal supraventricular tachycardia converted to sinus node rhythm. Five (60%) of the 8 patients with paroxysmal atrial flutter converted to sinus node rhythm. The average time of conversion, after completion of drug administration, was 15 +/- 20 minutes. The QRS was prolonged an average of 82 to 91 milliseconds; in those cases who converted, the PR interval duration was 180 milliseconds average; QT was prolonged an average of 425-450 milliseconds. There were no changes in the JT interval, and we observed no hemodynamic untoward effects.