Abstract

Objective: The recently introduced interventional techniques for treatment of Hypertrophic Obstructive Cardiomyopathy (HOCM) using DDD (VAT) Double Chamber Pacemaker Stimulation (DCP) and Transcoronary Ablation of Septal Hypertrophy (TASH) have changed the indication for Transaortic Subvalvular Myectomy (TSM) considerably. The therapeutic intention is to reduce the left ventricular outflowtract obstruction (LVOTO) and the sequelae as a palliative procedure. On this background the long-term results after TSM may serve as a so-called gold standard for CDP and TASH to reach or even to exceed!

Methods: Our surgical indication was always restrictive and currently include patients (pts.) in NYHA III after long-term failing medical treatment and after-failing DCP and TASH, with midventricular obstruction, children and adolescents, and pts. with simultaneously necessary additional cardiac interventions (CAD, ASD, valvular lesions, muscle bridge) in all NYHA classes after reanimation, syncope, and life-threatening tachyarrhythmias.

Results: Our surgical experience (1963--1997) is related to 516 pts., mean age 49 ± 11 years (range 3 mos--82 years). The total early lethality rate was 4.5% (n = 23), which could be reduced to 2.8% (1985--1994) and 1.7% (1995--1997).

A 100% follow-up could be completed between 1963 to 1991 (closing date 2/98) including 346 pts. During follow-up (28 years) late lethality was 11% (n = 38). Only 18 deaths were related to HOCM (5.2%).

During the observation time several hemodynamic, exertional, echocardiographic, and arrhythmia studies were performed and published indicating the functional improvement concerning complaints, exercise capacity, reduction of pulmonary artery and LV enddiastolic pressures, reduction of septal and LV-posterior wall hypertrophy and increase of diastolic function of the LV. The long-term survival rate (actuarial rate after 25 years: 74.2%) was superior to results after medication only. Our results are confirmed by recent publications from other centers (Aachen, Bethesda, Cleveland, Houston, Lyon, Rochester, Stanford, Toronto).

Conclusion: Surgical indications have changed for TSM after further development of interventional techniques (DCP; TASH) which seem to be acceptable for lower degree HOCM pts., and earlier intervention, however, for a special group of pts. the indication for TSM will persist. The collecting overview of the long-term results after TSM from European and American Centers may serve as the aims to be reached by interventional techniques.