Use of Intraoperative Dobutamine Stress Echocardiography on Outcomes of Septal Myectomy.

Background: Septal myectomy is the standard treatment for obstructive hypertrophic cardiomyopathy. We studied the impact of intraoperative pre- and post-procedure dobutamine stress transesophageal echocardiography on surgical planning and outcomes of septal myectomy. Methods: We identified 55 patients undergoing septal myectomy over a 24-month period. All patients underwent resting and dobutamine stress(20-40 mcg/kg/min) echocardiography after induction of anesthesia pre- and post-procedure. Demographic, clinical and imaging data were prospectively collected. Results: Mean age was 59(42-68). 69% of patients were NYHA Class III/IV. During outpatient evaluation, peak pre-operative resting left ventricular outflow tract gradient was 91.6mmHg and 94%(50/53) had severe stress-induced mitral regurgitation. After induction, peak resting gradient fell to 47.8mmHg and 43%(24/55) had improved gradients(