Impact of Severe Postoperative Multi-Organ Dysfunction on Long-Term Outcomes After Modified Morrow Surgery

The modified Morrow surgery is the gold standard surgical treatment for hypertrophic obstructive cardiomyopathy (HOCM). While effective, it carries a risk of postoperative severe multi-organ dysfunction and its impact on long-term cardiovascular outcomes remains poorly understood and controversial.

This observational cohort study included 380 HOCM patients undergoing the modified Morrow surgery between July 2015 and March 2025. Severe multi-organ dysfunction was defined as a maximum Sequential Organ Failure Assessment (SOFA) score ≥ 11. The primary endpoint was the long-term incidence of major adverse cardiac and cerebrovascular events (MACCEs). Secondary endpoints included heart failure hospitalization (HFH), postoperative atrial fibrillation (AF) ablation, and cardiovascular mortality.

Compared to patients without severe multi-organ dysfunction (SOFA Maximum < 11, n = 234), those with SOFA Maximum ≥ 11 (n = 146) had significantly higher rates of MACCEs (53.4% vs. 17.5%, p < 0.001), cardiovascular mortality (11.6% vs. 0.9%, p < 0.001), HFH (21.9% vs. 8.5%, p < 0.001), and postoperative AF ablation (17.8% vs. 3.8%, p < 0.001). Multivariable Cox proportional hazards regression demonstrated that severe multi-organ dysfunction was independently associated with cardiovascular mortality (HR = 4.157, p = 0.047), MACCEs (HR = 2.296, p < 0.001), HFH (HR = 1.834, p = 0.042), and postoperative AF ablation (HR = 3.987, p < 0.001). Other independent predictors included family history of hypertrophic cardiomyopathy, left ventricular end-systolic dimension, postoperative left ventricular outflow tract velocity, and postoperative surgical intensive care unit ventilation time.

Postoperative severe multi-organ dysfunction is independently associated with an increased risk of adverse long-term outcomes after modified Morrow surgery. Incorporating the SOFA score into postoperative risk stratification may help identify high-risk patients warranting intensified long-term management.