Left ventricular myocardial mass index as a predictor of spontaneous rhythm recovery after cardioplegia in patients with obstructive hypertrophic cardiomyopathy

Objective. To evaluate left ventricular myocardial mass index (LVMI) as a predictor of cardiac rhythm recovery after removal of aortic clamp during septal myectomy surgery in patients with hypertrophic cardiomyopathy. Material and methods. We retrospectively analyzed 196 patients who underwent septal myectomy in 2018—2023. Exclusion criteria: age <18 years, redo cardiac surgery, LV ejection fraction <30%, LV end-diastolic volume ≥250 ml. We used the following primary endpoints: spontaneous rhythm recovery, defibrillation in post-perfusion period, postoperative rhythm disturbances, acute heart failure. For analysis of perioperative parameters, we divided patients into two groups: spontaneous rhythm recovery (n=90) and reperfusion VF (n=106). Results. LVMI had high variability. Minimum aortic cross-clamping time was 23 min, maximum — 172 min. None patient required long-term inotropic and mechanical support. When comparing rhythm recovery, we found significant differences in LVMI (p=0.022). AUC exclusively for LVMI was 0.595±0.041 (95% CI 0.515—0.675). This model was significant (p=0.022). Cut-off LVMI corresponding to the highest Yuden index was 173. Conclusion. Along with other intraoperative factors, LVMI may be a predictor of spontaneous rhythm recovery after cardioplegia in patients with hypertrophic cardiomyopathy. The probability of spontaneous rhythm recovery was significantly lower in patients with LVMI >173.