[Improved myocardial function after transluminal coronary angioplasty (author's transl)]

To assess the results of transluminal coronary angioplasty (TCA), 42 patients (mean age 50 years) with for coronary artery disease were investigated at rest and during exercise with the ECG (n = 40), thallium-201 myocardial scintigraphy (n = 23) and equilibrium-radionuclide ventriculography (n = 32). Each method of stress testing was quantified: the exercise ECG by means of an ischemia score, incremented with increasing ST-segment depression and decremented as a function of duration of exercise and workload in watts; thallium-201 scintigraphy by means of an index for minimal to maximal perfusion region (vitality index) and redistribution factors; equilibrium-radionuclide ventriculography by means of global ejection fraction and maximum systolic volume change with respect to the end-diastolic volume. The patients were divided into three groups: 30 had successful TCA defined as demonstrating at least a 20% reduction in the stenosis; six underwent aortocoronary bypass operation (nine grafts; complete revascularization in four patients); and in six patients TCA was unsuccessful. TCA was successful in 24 LAD stenoses, 5 RCA stenoses, and in one proximal anastomosis of an aortocoronary bypass graft. Dilatation could not be achieved in three LAD stenoses and three stenoses of the RCA. In those in whom it was successful, TCA yielded an average reduction of coronary artery stenosis from 84 to 43%. Both TCA and bypass operation (OP) led to comparable degrees of functional improvement. The ischemia score decreased from 2.8 to 0.9 after TCA and from 1.6 to 0 after OP. The vitality index increased from 67 to 77% and from 74 to 81% after TCA and OP respectively while the corresponding redistribution factors decreased (TCA: at 1 hour from 5 to 1% and at 3.5 hours from 11 to 4%; OP: at 1 hour from 2.2 to 1.4% and at 3.5 hours from 7.6 to 4.1%. The global ejection fractions at rest improved from 46 to 52% and from 38 to 45% and during exercise from 42 to 50% and from 36 to 43% after TCA and OP respectively. The maximum--dV/dt/EDV increased at rest (TCA: from 2.7 to 3.5 per second; OP: from 2.1 to 3.8 per second) and during exercise (TCA: from 3.1 to 4.0 per second; OP: from 2.6 to 3.3 per second). In the group with unsuccessful TCA, no significant differences in the latter parameters were observed. Ten of the 30 patients who had undergone successful dilatation were reinvestigated after three months. Maintenance of good functional results could be documented in eight while deterioration was seen in two patients, one with a significant restenosis and one who developed a new narrowing distal to the successfully dilated stenosis. Thus, the results show that in selected cases, TCA can render improved ventricular function and perfusion comparable to that of aortocoronary artery bypass surgery.