Sex-based outcomes of surgical myectomy for hypertrophic cardiomyopathy: An analysis from the National Readmission Database

Background: There is a paucity of data on sex differences in outcomes after surgical myectomy (SM) for hypertrophic cardiomyopathy (HCM). Methods: Patients who received SM for HCM during October 1, 2015, through December 31, 2018, were identified from the US National Readmission Database. The primary end point of this study was in-hospital mortality. The secondary end points were major bleeding, acute kidney injury, new pacemaker implantation, severe disability surrogates (non-home discharge and need for mechanical ventilation), resources utilization surrogates (length of stay and cost of hospitalization), and 30-day outcomes (readmission rate, mortality, and new pacemaker insertion). Results: A total of 3031 patients were included in the current analysis. Using propensity score matching, 2 well matched cohorts were compared (women = 1170 and men = 1127). Women had a higher requirement for new pacemaker insertion compared with men (10.9% vs 6.8%; P = .029), higher number of non-home discharges (13.8% vs 7.9%; P < .01), and longer length of hospital stay (median = 7 [interquartile range, 5-9] days) versus (median = 6 [interquartile range, 5-8] days). There was no difference in in-hospital mortality, major bleeding, blood transfusion, acute kidney injury, or hospitalization costs for women versus men. At 30 days, women continued to show a higher need for pacemaker insertion (11.3% vs 7.1%; P = .03) and had a higher readmission rate than men (10.9% vs 7.1%; P = .02). There was no difference in 30-day mortality between women and men (3% vs 2.4%; P = .54). Conclusions: Among the HCM cohort who received SM, significant sex-based differences in the outcomes were observed. Women had higher new pacemaker insertion rate, higher non-home discharge rate, and higher rate of 30-day readmission compared with men.