Comparison of myectomy alone or in combination with mitral valve repair for hypertrophic obstructive cardiomyopathy.

Unlabelled: Between 1/84 and 6/91 56 patients were treated for hypertrophic obstructive cardiomyopathy (HOCM): the Morrow technique alone was performed on 40 patients (group 1), in 16 patients (group 2) an additional replacement (n = 13) or reconstruction (n = 3) of the mitral valve was indicated. In a total of 14 cases coronary artery bypass grafting and aortic valve replacement was performed in addition. Postoperatively (mean follow-up 4.2 yrs, 141 patient-years) left-ventricular diastolic and systolic function parameters, heart muscle mass, ECG findings, and symptomatology were recorded and the ratios of beta-adrenoreceptor density to density of the calcium channel were measured.

Results: Pressure gradient decreased from 69.2 +/- 5.2 (group 1) and 75.1 +/- 4.8 (group 2) to 23.3 +/- 2.7 and 11.7 +/- 2.2 mmHg postoperatively. Likewise Sokolow-Lyon index decreased from 3.5 +/- 0.2/3.7 +/- 0.2 to 2.9 +/- 0.2/2.8 +/- 0.3. The quotient time-to-peak-velocity/left-ventricular-ejection-time decreased significantly in group 2 from 58.6 +/- 6.3 to 41.9 +/- 5.8 (p less than 0.05). The heart muscle mass, determined echocardiographically, decreased from 680g to 430g (p less than 0.05). Isovolumetric tension time, isovolumetric relaxation time, and E/A ratio at rest and after stress showed typical characteristics. Ca(++)-channel density was clearly raised in all patients, with no differences between the two groups being observable. We conclude from our results: The most marked improvements in clinical and left-ventricular functional parameters were experienced by patients in group 2 (myectomy+MVR).(ABSTRACT TRUNCATED AT 250 WORDS)