Purpose. To study the diagnostic value of heart rate variability (HRV) individual parameters analysis, left ventricle ejection fraction (LVEF) assessment and cardiac 123I-methaiodobenzylguanidine (123I-MIBG) scintigraphy in the VTA prediction in patients with CAD and high risk of sudden cardiac death SCD.
Methods. 30 patients (male - 22, female - 8, average age 66,9±8,6 year) with CAD, myocardial infarction and secondary SCD prevention indications were examined. Before ICD implantation, patients underwent echocardiography, HRV individual parameters analysis and cardiac 123I-MIBG scintigraphy. All patients were treated with antiarrhythmic therapy (beta-blockers and amiodarone). All patients were divided into 2 groups according to the incidences VTA events during sixth months’ follow-up. The first group consisted of patients with VTA events, second group - without VTA. Data of HRV, LVEF and cardiac 123I-MIBG scintigraphy before ICD implantation were compared.
Results. The 1-st group consisted of 19 (63,3%) patients with VTA events (male - 15, female - 4, age 66,4±9,1 years). The 2-nd group consisted of 11 (36,7%) patients without VTA events (male - 7, female - 4, age 67,7±8,1 years). There were statistically significant differences between patients with and without VTA before ICD implantation in terms of: LVEF - 50,63±9,22% vs. 64,18±7,96% (p=0,001), low frequencies domain - 719,47±437,83 ms vs. 1385,01±889,98 ms (p=0,01), total frequencies domain - 1910,63±882,04 ms vs. 2830,81±1208,61 ms (p=0,04), summed 123I-MIBG score calculation on early (31,68±17,71% vs. 7,36±2,24% (p=0,0005)) and delayed (33,05±18,08 vs. 9,36±3,93% (p=0,0003)), respectively. Conclusion. HRV assessment, as well as LVEF and cardiac sympathetic activity assessment can be used for identification of SCD highest risk group. But cardiac 123I-MIBG scintigraphy is more powerful predictor of VTA events then heart rate variability and left ventricle systolic function assessment in patients with CAD.