A Vegh1, L Szekeres, J R Parratt. 1. Institute of Pharmacology, Albert Szent-Gyorgyi Medical University, Szeged, Hungary.
Abstract
STUDY OBJECTIVE: The aim was to determine whether rapid ventricular pacing can protect against the ventricular arrhythmias occurring during a subsequent coronary artery occlusion. DESIGN: The effect was examined of two 2 min periods of pacing (300 beats.min-1) in chloralose-urethane anaesthetised dogs on a subsequent 25 min coronary artery occlusion. Ventricular arrhythmias, ST segment elevation, and inhomogeneity of conduction were analysed. EXPERIMENTAL MATERIAL: 25 anaesthetised mongrel dogs in a restricted body weight range were used. MEASUREMENTS AND MAIN RESULTS: Preocclusion pacing reduced the severity of occlusion induced ST segment elevation, degree of inhomogeneity, and arrhythmias: ventricular premature beats were reduced from 528(SEM 40) to 136(45), and there were lower incidences of ventricular fibrillation (0% v 47%) and ventricular tachycardia (30% v 80%). CONCLUSIONS: Rapid ventricular pacing "preconditions" the myocardium in a manner similar to that following short coronary artery occlusions. Short periods of ischaemia no matter how induced protect the heart against the arrhythmogenic effect of a prolonged coronary artery occlusion.
STUDY OBJECTIVE: The aim was to determine whether rapid ventricular pacing can protect against the ventricular arrhythmias occurring during a subsequent coronary artery occlusion. DESIGN: The effect was examined of two 2 min periods of pacing (300 beats.min-1) in chloralose-urethane anaesthetised dogs on a subsequent 25 min coronary artery occlusion. Ventricular arrhythmias, ST segment elevation, and inhomogeneity of conduction were analysed. EXPERIMENTAL MATERIAL: 25 anaesthetised mongrel dogs in a restricted body weight range were used. MEASUREMENTS AND MAIN RESULTS: Preocclusion pacing reduced the severity of occlusion induced ST segment elevation, degree of inhomogeneity, and arrhythmias: ventricular premature beats were reduced from 528(SEM 40) to 136(45), and there were lower incidences of ventricular fibrillation (0% v 47%) and ventricular tachycardia (30% v 80%). CONCLUSIONS: Rapid ventricular pacing "preconditions" the myocardium in a manner similar to that following short coronary artery occlusions. Short periods of ischaemia no matter how induced protect the heart against the arrhythmogenic effect of a prolonged coronary artery occlusion.
Authors: Kieran McCafferty; Conor J Byrne; Julius Kieswich; Martin Raftery; Christoph Thiemermann; Muhammad M Yaqoob Journal: Heart Asia Date: 2014-05-24
Authors: Peter E Penson; William R Ford; Emma J Kidd; Kenneth J Broadley Journal: Naunyn Schmiedebergs Arch Pharmacol Date: 2008-07-29 Impact factor: 3.000