958-100 Myocardial Preconditioning During Repeated Daily Ischemic Episodes

Abstract

Myocardial preconditioning was described in animal experiments and also on repeated coronary occlusions during coronary angioplasty, however, it has never been described during daily life. Twenty-three patients with proven coronary disease and episodes of ischemia on Holter monitoring were instructed to walk the same route, which previously caused myocardial ischemia, 3 times within 45 minutes (15 minutes each walk). The duration of ischemia (per patient), maximal ST depression (STD), and the ST level at a uniform heart rate (normalized STD) for all 3 walks for every patient were recorded. Walk p 1 2 3 walk 1vs 2 walk 1 vs 3 Ischemia Duration (sec) 514 228 253 0.003 0.003 Maximal STD (mm) 2.21 1.61 1.43 0.001 0.0002 Normalized STD (mm) 1.95 1.41 1.18 0.0002 0.00001 Max. Heart Rate (b/min) 113 112 113 0.793 0.974 These data indicate that during repeated ischemic episodes, for the same maximal heart rates, there was a reduction in duration of ischemia, in maximal ST depression and a reduction in the normalized STD. This is the first description of myocardial preconditioning during daily life, and it may provide explanation for the well-known phenomenon of “walk-through-angina”