Diastolic dysfunction in cardiac transplant recipients: an important role in the response to increased afterload.

We evaluated the hemodynamic and functional response to acute elevations in left ventricular (LV) afterload in 22 recent recipients of cardiac transplants to determine whether abnormalities in LV diastolic function influence the response to this intervention. In seven patients (group 1) LV ejection fraction decreased significantly from baseline values (> or = 5%) during methoxamine infusion, whereas in 15 patients (group 2) LV ejection fraction was maintained. Peak filling rate was lower in group 1 versus group 2 (3.36 +/- 0.46 vs 4.23 +/- 0.68 end-diastolic volumes/sec, p < 0.01). In addition, patients in group 1 did not have LV dilatation during methoxamine (percentage change in end-diastolic counts, -3.4 +/- 6.9%) and had a large increase in pulmonary artery wedge pressure. In contrast, patients in group 2 had LV dilatation (percentage change in end-diastolic counts, +10.7 +/- 14.7%) and a smaller increase in pulmonary artery wedge pressure. There was a relationship between the baseline peak filling rate and the change in LV ejection fraction during methoxamine (r = 0.65, p = 0.001). Therefore in a subset of cardiac transplant patients, abnormalities in LV filling can have an impact on the response to increased afterload.