Sudden Cardiac Death II
Abstract
Heart rate turbulence (HRT) is a useful predictor of SCD in post-MI patients. Relationship between left ventricle (LV) dysfunction and a decrease in turbulence may affect the prognostic significance of HRT. Purpose of the study was to analyse HRT indices in post-MI patients, with ICD implanted in primary and secondary prevention, with regard to the level of LV dysfunction. A group of 133 patients with previous (>40 days) MI (without diabetes, sinus rhythm, 30% had similar TO: −0.5 ± 1 vs. −1 ± 1%, P = 0.18, but significantly lower TS: 2.7 ± 1.4 vs. 4.8 ± 3.3 ms/rri, P = 0.02. VT/VF subgroup with LVEF ≤30% had similar turbulence parameters to NoVT/VF subjects—TO: 0 ± 1.3 vs. −0.3 ± 1.2%, P = 0.36 and TS: 2.1 ± 1.8 vs. 2.4 ± 1.2 ms/rri, P = 0.53, HRT2 was more frequent in VT/VF (28 patients, 54%) than in NoVT/VF (4 patients, 25%), P = 0.05. In conclusion, HRT differentiates patients with VT/VF with a moderate, but not severe LV dysfunction. It may suggest that turbulence is a marker of both systolic LV dysfunction and susceptibility to VT/VF occurrence.