Abstract Body (Do not enter title and authors here): Background: Sex differences in patients with obstructive hypertrophic cardiomyopathy (HCM) who undergo septal myectomy remain unclear. This study evaluated sex disparities in a large Chinese cohort undergoing HCM 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-year older and had 1-year longer disease onset-to-surgery delay than men. They were more frequently in NYHA class III/IV and had more severe left ventricular outflow tract obstruction. Compared with men, women had a notably higher LV wall thickness index and a lower extent of LGE. Women also had more mutations in MYH7 and fewer in MYBPC3. Postoperatively, women had a higher operative mortality rate (1.3% vs. 0.1%, p=0.006), longer ventilation time, and longer postoperative stay. The follow-up results showed no significant difference between the sexes in all-cause mortality (HR 0.72 [0.41 - 1.29], p= 0.274). A U-shaped association was observed between age and mortality in the overall population. However, women exhibited this association more obviously at ≥55 years of age and men at<35 years. Moreover, women also had a higher risk of cardiovascular re-hospitalization after surgery (HR 1.43 [1.05-1.94], p=0.021).
Conclusions: Women had a similar fatal outcome while 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.