Changes in myocardial perfusion due to physical exercise in patients with stable coronary artery disease

Percutaneous transluminal coronary angioplasty (PTCA) is one of the main therapy options for patients with coronary artery disease (CAD), resulting in an improvement in myocardial perfusion and exercise capacity. Nevertheless, studies have also demonstrated a positive effect of regular exercise training on myocardial perfusion and maximum exercise capacity. The aim of this study was to evaluate changes in myocardial stress perfusion after 1 year of exercise training in comparison with the effects of PTCA in patients with CAD.

In 66 male patients with angiographically confirmed significant coronary artery stenosis in one target vessel, myocardial perfusion scintigraphy was performed at baseline and 12 months after randomisation into either a physical exercise group or a PTCA group. Circumferential count rate profiles in 16 wall segments were classified according to their relative count rate and localisation within or outside the area supplied by the stenosed vessel.

Ischaemic segments showed a significant improvement in myocardial count rate within the target area after 12 months in both the PTCA and the training group (PTCA group: from 76.8+/-4.9% to 86.6+/-10.9%, p=0.03; training group: from 74.0+/-7.3% to 83.7+/-10.8%, p<0.01). Outside the target area only the training group showed a significant improvement (from 77.7+/-4.4% to 91.7+/-4.8%, p<0.01).

Our data indicate a significant improvement in stress myocardial perfusion in the training group after 12 months. The ischaemia is reduced not only in the target region of the leading stenosis but also in other ischaemic myocardial areas. In contrast, after PTCA stress perfusion improves only in the initially ischaemic parts of the target area.