Preoperative D-dimer and outcomes in obstructive hypertrophic cardiomyopathy after myectomy

The prognostic significance of D-dimer in patients with hypertrophic cardiomyopathy undergoing septal myectomy has not been well established.

We retrospectively analyzed D-dimer levels in 728 patients who underwent septal myectomy at our hospital between 2009 and 2018. Baseline D-dimer levels were categorized into tertiles (<0.21, 0.21-0.3, ≥0.3 mg/L) The primary and secondary endpoints were all-cause mortality and cardiovascular mortality, respectively. Cox regression and competing risk models were used to evaluate risk factors for all-cause and cardiovascular mortality, respectively.

Higher D-dimer levels were associated with older age, female sex, more severe mitral regurgitation, and elevated N-terminal pro B-type natriuretic peptide levels (P < 0.05). Over a median follow-up of 4.2 years, 31 (4.3 %) patients reached the primary endpoint; 23 deaths were attributed to cardiovascular causes. The optimal cutoff D-dimer level for predicting 5-year mortality was 0.29 mg/L. After adjusting for covariates, D-dimer levels of >0.29 mg/L were significantly associated with an increased risk of all-cause mortality (hazard ratio [HR], 3.12; 95 % confidence interval [CI], 1.42-6.86; p = 0.005) and cardiovascular mortality (HR, 3.29; 95 % CI, 1.12-9.62; p = 0.030). Body mass index and left atrial diameter were also independent predictors of both all-cause mortality (HR, 1.12; p = 0.026, and HR, 1.08; p = 0.006, respectively) and cardiovascular mortality (HR, 1.12; p = 0.043, and HR, 1.11; p = 0.004, respectively). The inclusion of D-dimer levels of >0.29 mg/L improved the net reclassification index for all-cause mortality (p = 0.016).

D-dimer is a robust predictor of mid-to-long-term all-cause and cardiovascular mortality in patients undergoing septal myectomy.