Understanding Sex Differences in Hypertrophic Cardiomyopathy Surgery: Insights From a Decade-Long Cohort Study From China.

Abstract

Background: Sex differences in patients with hypertrophic cardiomyopathy have been elaborated by many studies. However, large studies of the association of patient sex with outcomes after surgical myectomy are scarce. This study evaluated sex disparities in a large Chinese cohort undergoing hypertrophic cardiomyopathy surgery.

Methods: The cohort encompassed 1613 patients, including 627 (38.9%) women who underwent septal myectomy between 2009 and 2018.

Results: At the time of surgery, women were 6 years older and had 1 year longer disease onset-to-surgery delay than men. They were more frequently in New York Heart Association class III/IV and had more severe left ventricular outflow tract obstruction. Compared with men, women had a notably higher left ventricular wall thickness index and a lower extent of late gadolinium enhancement. Women also had more mutations in MYH7 and fewer in MYBPC3. Postoperatively, women had a higher operative mortality rate (1.3% versus 0.1%, P=0.006). The follow-up results showed no significant difference between the sexes in all-cause death (hazard ratio [HR], 0.67 [95% CI, 0.38-1.18]; P=0.166). A U-shaped association was observed between age and death in the overall population. However, women exhibited this association more obviously at age ≥55 years and men at <35 years. Moreover, women also had a higher risk of cardiovascular rehospitalization after surgery (HR, 1.40 [95% CI, 1.03-1.89]; P=0.030).

Conclusions: In patients with obstructive hypertrophic cardiomyopathy, women had a similar fatal outcome but a worse nonfatal outcome than men after surgery. Measures improving quality of life may further enhance the event-free survival of female patients. Close monitoring and follow-up are warranted, especially in younger men and older women.