[Stress reaction of pulmonary artery pressure in the early and chronic phase after heart transplantation: comparison with healthy control probands].

The pulmonary artery pressure response to exercise frequently reflects ventricular diastolic properties. The aim of this study was to determine noninvasively cardiac allograft function and pulmonary artery pressure response to stress in the early and late phases after heart transplantation (HTX). Ten patients in the early postoperative phase (3.7 +/- 1.6 months postoperatively, group I) and ten patients at least 2 years after HTX (34.3 +/- 8.3 months postoperatively, group II) were studied by two-dimensional (2 D-), M-Mode, and Doppler echocardiography during supine graded bicycle exercise (25, 50, 75, 100 watts). The patients' data were compared to those obtained in eight normal controls. The peak pressure gradient between the right ventricle and right atrium during systole was derived from saline contrast-enhanced Doppler echocardiography of the tricuspid regurgitant jet and used as an estimate of pulmonary artery systolic pressure. In group I- and group II-patients, resting and exercise left ventricular diameters as well as systolic function were normal. The right ventricle was enlarged (3.2 +/- 0.4 cm/3.0 +/- 0.6 cm in group I/group II versus 2.1 +/- 0.3 cm in normal controls, p < 0.05). During exercise, heart rate increased less in heart transplant recipients (+26%/+36% in group I/group II, p < 0.05) than in normals (+67% at 100 watts, p < 0.05). Resting pulmonary artery pressures were similar in heart transplant recipients in the early and late postoperative stage and in normals.(ABSTRACT TRUNCATED AT 250 WORDS)