Clinical features and postoperative outcomes in elderly patients undergoing septal myectomy for hypertrophic cardiomyopathy.

Objectives: Surgical septal reduction is sometimes avoided in older adults due to anticipated high operative risk. The study objectives were to compare the clinical and echocardiographic characteristics of young and older patients undergoing septal myectomy for obstructive hypertrophic cardiomyopathy and assess differences in early and late postoperative outcomes.

Methods: A total of 2663 patients with obstructive hypertrophic cardiomyopathy underwent transaortic septal myectomy between 2000 and 2021 and were categorized by age: 18 to 64 years, 65 to 74 years, and 75 years or more.

Results: Median age at the time of surgery increased over the study interval. Female sex (P < .001), hypertension P < .001), and diabetes (P = .004) were more prevalent in older patients, but extent of functional limitation (New York Heart Association) was similar (P = .092). Elderly patients had thinner septal and posterior walls (P < .001, P = .006) and less prominent asymmetry (P < .001). They are less likely to have positive genetic testing. Hospital mortality was 0.2%, 0.5%, and 1.3% in patients aged less than 65 years, 65 to 74 years, and 75 years or more, respectively (P = .06), and 5-year survivals were 97%, 93%, and 91%, respectively. Septal-to-posterior wall thickness ratio significantly correlated with increased mortality in patients aged more than 65 years, but not in patients aged less than 65 years (P = .92). Most of the patients reported improved quality of life after myectomy.

Conclusions: Clinical characteristics of obstructive hypertrophic cardiomyopathy in older patients differ from those in younger patients. More symmetric but less extensive ventricular hypertrophy and less positive genetic testing suggests that hypertrophic cardiomyopathy has distinct clinical and morphological variants in the elderly. Septal myectomy is safe in older patients, but the presence of left ventricular wall asymmetry portends a poorer prognosis.