Introduction: In late 1997, the German Cardiac Society set up a multicenter registry to evaluate the acute and mid-term course of all patients (pts.) treated with septal ablation for symptomatic hypertrophic obstructive cardiomyopathy (HOCM). An analysis of the acute results has already been published. We now report on the mid-term course (3-6 months) of 242 pts. registered through September 1999.
Results: Follow-up was 92% complete (n=222). During follow-up (mean: 4.9+/-2.3 months), an additional 3 pts. died (in-hospital mortality: 3 pts.). A satisfactory clinical effect was reported by 195 pts. (88%); 27 pts. (12%) remained in NYHA classes III and IV. Overall symptomatic improvement (NYHA class: from 2.8+/-0.7 to 1.7+/-0.7) paralleled the outflow gradient (LVOTG) reduction which was further accentuated as compared with the acute result (Doppler measurement at rest: from 57+/-31 to 25+/-25 mmHg to 20+/-21 mmHg; with provocation: from 107+/-53 to 49+/-40, to 44+/-40 mmHg, p<0.001, resp.). Left atrial (LA) diameter (from 46+/-8 to 44+/-7 mm) and septal thickness (from 20+/-5 to 15+/-5 mm; p<0.001, resp.) were also reduced. Comparing the methods for target vessel selection (i.e., with contrast echo monitoring vs pressurefluoroscopy guidance), at followup clinical improvement and hemodynamic measurements were comparable.
Conclusion: Clinical success can be achieved by septal ablation, both with the echocontrast guided and gradient-fluoroscopy guided method, in 88% of highly symptomatic HOCM pts. At mid-term follow-up, symptoms, left atrial size and septal thickness are reduced, and outflow gradients are further improved as compared to the acute result.