INTRODUCTION: In this study systolic and diastolic function in patients with hypertrophic obstructive cardiomyopathy (HOCM) and intractable complaints to medication were investigated before and after a mean of 7 months after myectomy. METHODS: Investigations in 19 patients with HOCM included echocardiography, Swan-Ganz-thermodilution-catheter and radionuclide-angiography. RESULTS: Myectomy resulted in a reduction of the intraventricular gradient at rest (40.1 +/- 43.3 versus 7.6 +/- 12.0 mm Hg, p < or = 0.005) and under provocation (92.4 +/- 67.1 versus 21.3 +/- 26.5 mm Hg, p < or = 0.001). Echocardiographically determined basal septal thickness was reduced (24.9 +/- 6.3 versus 20.1 +/- 6.8 mm; p < or = 0.05) and diastolic diameter increased (40.4 +/- 5.2 versus 44.8 +/- 7.1; p < or = 0.05). Exercise tolerance increased from the maximally achieved 64.5 +/- 19.2 to 89.5 +/- 24.0 W (p < or = 0.001). Symptomatic status (NYHA) improved (1.7 +/- 1.4 versus 2.8 +/- 0.3 (p < or = 0.001). Systolic parameters showed at rest an increase in isovolumetric contraction time (65 +/- 39 versus 112 +/- 50 ms, p < or = 0.01), in time to peak ejection (109 +/- 40 versus 188 +/- 42 ms, p < or = 0.001), and a reduced left ventricular ejection fraction (72 +/- 12 versus 64 +/- 11%, p < or = 0.01). Analysis of regional ejection fraction revealed a significant reduction of ejection fraction in the basal septal region (p < or = 0.05). Increase of global and regional ejection fraction under exercise was still preserved. Mean pulmonary capillary wedge pressure was significantly reduced at rest (11.8 +/- 3.8 versus 8.6 +/- 2.4 mm Hg, p < or = 0.05) as well as under exercise (27.0 +/- 7.1 versus 20.4 +/- 6.8 mm Hg, p < or = 0.01), whereas left ventricular enddiastolic volume index (63 +/- 19 versus 72 +/- 17 ml*m-2, p < or = 0.05) was significantly increased. CONCLUSIONS: In patients with HOCM, myectomy reduces intraventricular gradient, increases exercise capacity, and is accompanied by improved diastolic function parameters, while systolic function parameters are generally reduced.
INTRODUCTION: In this study systolic and diastolic function in patients with hypertrophic obstructive cardiomyopathy (HOCM) and intractable complaints to medication were investigated before and after a mean of 7 months after myectomy. METHODS: Investigations in 19 patients with HOCM included echocardiography, Swan-Ganz-thermodilution-catheter and radionuclide-angiography. RESULTS: Myectomy resulted in a reduction of the intraventricular gradient at rest (40.1 +/- 43.3 versus 7.6 +/- 12.0 mm Hg, p < or = 0.005) and under provocation (92.4 +/- 67.1 versus 21.3 +/- 26.5 mm Hg, p < or = 0.001). Echocardiographically determined basal septal thickness was reduced (24.9 +/- 6.3 versus 20.1 +/- 6.8 mm; p < or = 0.05) and diastolic diameter increased (40.4 +/- 5.2 versus 44.8 +/- 7.1; p < or = 0.05). Exercise tolerance increased from the maximally achieved 64.5 +/- 19.2 to 89.5 +/- 24.0 W (p < or = 0.001). Symptomatic status (NYHA) improved (1.7 +/- 1.4 versus 2.8 +/- 0.3 (p < or = 0.001). Systolic parameters showed at rest an increase in isovolumetric contraction time (65 +/- 39 versus 112 +/- 50 ms, p < or = 0.01), in time to peak ejection (109 +/- 40 versus 188 +/- 42 ms, p < or = 0.001), and a reduced left ventricular ejection fraction (72 +/- 12 versus 64 +/- 11%, p < or = 0.01). Analysis of regional ejection fraction revealed a significant reduction of ejection fraction in the basal septal region (p < or = 0.05). Increase of global and regional ejection fraction under exercise was still preserved. Mean pulmonary capillary wedge pressure was significantly reduced at rest (11.8 +/- 3.8 versus 8.6 +/- 2.4 mm Hg, p < or = 0.05) as well as under exercise (27.0 +/- 7.1 versus 20.4 +/- 6.8 mm Hg, p < or = 0.01), whereas left ventricular enddiastolic volume index (63 +/- 19 versus 72 +/- 17 ml*m-2, p < or = 0.05) was significantly increased. CONCLUSIONS: In patients with HOCM, myectomy reduces intraventricular gradient, increases exercise capacity, and is accompanied by improved diastolic function parameters, while systolic function parameters are generally reduced.