The Midlands Trial of Empirical Amiodarone versus Electrophysiology-guided Interventions and Implantable Cardioverter-defibrillators (MAVERIC): a multi-centre prospective randomised clinical trial on the secondary prevention of sudden cardiac death.

AIMS: MAVERIC was a randomised clinical trial designed to test the possibility of prospectively identifying patients who would benefit most from the implantable cardioverter-defibrillator (ICD) by electrophysiology (EP) study in the context of secondary prevention of sudden cardiac death (SCD) through comparing EP-guided interventions (anti-arrhythmic drugs, coronary revascularization, and ICD) against empirical amiodarone therapy. METHODS: Two hundred and fourteen survivors of sustained ventricular tachycardia (VT), ventricular fibrillation (VF) or SCD were randomized to either treatment strategy, pre-stratified for haemodynamic status at index event, and followed up for a median of 5 years. RESULTS: Of the 106 amiodarone arm patients, 89 (84%) received the drug and 5 (5%) received an ICD after crossing over. Of the 108 EP arm patients, 31 (29%) received an ICD, 46 (43%) received anti-arrhythmic drugs only (mainly amiodarone or sotalol) and 18 (17%) received coronary revascularization but no ICD. No significant differences in survival or arrhythmia recurrence existed between the two treatment arms after 6 years. However, ICD recipients had a lower mortality than non-ICD recipients, regardless of allocated treatment (hazard ratio=0.54, p=0.0391). CONCLUSIONS: Prospective selection of patients to receive the ICD by EP study did not improve survival compared with empirical amiodarone therapy among survivors of VT, VF or SCD, whereas ICD implantation improved survival regardless of allocated treatment. On this basis, routine EP study has no role in the management of such patients, who should be offered empirical ICD therapy according to the results of other secondary prevention ICD trials.

Effect of liver transplantation on QT interval prolongation and autonomic dysfunction in end-stage liver disease.

Both a prolonged QT interval and disturbance of autonomic nervous system function are markers of poor prognosis in patients with diabetes mellitus and alcoholic liver disease (ALD). We studied the prevalence of abnormal QT interval and autonomic nervous system dysfunction in 53 consecutive patients with end-stage liver disease before and after orthotopic liver transplantation (OLT). The maximum QT interval in any lead (QTmax) was assessed by two independent observers. The QTmax, corrected for heart rate (QTcmax) was prolonged in 44 patients (83%), although increased QT dispersion was not found. There was a significant correlation between the QTcmax and Child-Pugh score but not with etiology. Evidence of parasympathetic dysfunction was present in 41 patients (77%), and sympathetic dysfunction was present in 20 patients before OLT. Fifty-two patients underwent transplantation. There was significant improvement in the QTcmax interval after OLT (P < .001); 32 of the 44 patients with prolonged QTcmax ( > 440 milliseconds) improved. Repeat testing was not performed in 7 patients, because they had died or had not undergone transplantation. Indices of parasympathetic function improved in 27 patients after OLT, but no improvement was observed in 8. Improvement in sympathetic dysfunction was observed in 13 of the 19 patients tested. There was no association between QTcmax, autonomic dysfunction, and survival. These results suggest that both prolonged QTcmax and some tests of autonomic function are temporary and arise as a consequence of liver dysfunction.