Changes of the Degree of Hypertrophy in Hypertrophic Obstructive Cardiomyopathy under Medical and Surgical Treatment

Abstract

The aim of our study was to establish the extent to which therapy of hypertrophic obstructive cardiomyopathy (HOCM) can influence the degree of hypertrophy. By means of two-dimensionally guided M-mode echocardiography, 120 patients with HOCM (age range 4–72 years, mean age 41 years) were observed over an average period of 49 ± 41 months. Depending on the respective therapy, we formed four patient groups: group 1:13 patients without any therapy (follow-up period 31 ± 30 months); group 2: 27 patients receiving propranolol (follow-up period 47 ± 34 months); group 3: 50 patients receiving verapamil (follow-up period 39 ± 27 months), and group 4: 30 patients with myectomy (follow-up period 34 ± 32 months). In group 4, as expected, the thickness of the interventricular septum (IVS) decreased postoperatively (from 24.2 ± 4.5 to 19.8 ± 6.7 mm, p < 0.05), and the left ventricular posterior wall (LVPW) thickness also decreased later postoperatively (from 13.0 ± 2.6 to 11.9 ± 2.3 mm, p < 0.05). The left ventricular diameters increased. In groups 2 and 3 treated with pharmacotherapy as in the untreated patients of group 1 on average there was no change in IVS and LVPW thickness nor in the left ventricular diameters (with the exception of increasing left ventricular end-diastolic diameter in the propranolol-treated group). In contrast to group 1 in occasional cases there were substantial decreases of IVS thickness (11% of the patients in group 2, 13 % in group 3) or LVPW thickness (13% of the patients in group 2, 12% in group 3). However, the thickness remained mainly unchanged (IVS: 74% of the patients in group 2, 71% in group 3; LVPW: 67% in group 2, 70% in group 3) or increased (IVS: 15% in group 2, 17% in group 3; LVPW: 21 % in group 2, 19% in group 3). The differences between groups 2 and 3 were not significant. Thus, our investigations indicated that on average neither propranolol nor verapamil leads to a regression of hypertrophy in HOCM.

Medical therapy versus interventional therapy in hypertropic obstructive cardiomyopathy

“…Similar findings have been reported after surgical myectomy [36]. Furthermore, some groups report reduction of both left ventricular end diastolic pressure and mean pulmonary arterial pressure [25,35].…”

A Decade of Percutaneous Septal Ablation in Hypertrophic Cardiomyopathy

“…55 A reduction in free wall thickness has also been described after myectomy, implying that the increased afterload in HOCM may boost left ventricular hypertrophy, which can be subsequently lessened with effective reduction of the LVOT gradient. 56 Changes in coronary blood flow after PTSMA have been investigated with various methods. Invasive assessment of coronary flow reserve shows an immediate improvement after PTSMA as a result of the reduced contraction load of the left ventricle.…”

Current status of alcohol septal ablation for patients with hypertrophic cardiomyopathy

“…As in surgical myectomy [38], these findings must be interpreted as a result of the elimination (or at least reduction) of the pressure overload. Negative effects of the induced septal infarction, especially left ventricular enlargement, have not been described.…”