Predictive factors and long-term evolution of early endothelial dysfunction after cardiac transplantation

Background: Abnormal coronary vasomotion appears to be a common finding aft er heart transplantation (HTx). However, the pathophysiology and outcome of this functional disturbance remains poorly understood. Aims of the study w ere to determine the prevalence, predictive factors and long-term evolution of endothelial dysfunction after cardiac transplantation. Methods: The endothelium-dependent coronary vasomotion of 50 patients, who showed angiographically normal coronary arteries, were studied early (at 3 +/- 1 months) and at follow-up (16 +/- 5 months) after HTx. Endothelial fun ction was studied by selective infusion of serial doses of acetylcholine (A Ch) (10(-8), 10(-7) and 10(-6) mol/l) in the left anterior descending coron ary artery. Changes in mean luminal diameter after the infusion of each dos e were evaluated by quantitative coronary angiography (QCA). Results: At early study, 17 patients (34%) showed a vasoconstriction after maxima; dose of ACh (-13.3 +/- 13%) indicative of endothelial dysfunction. Logistic regression analysis identified the following Variables as independ ent predictors of early endothelial dysfunction: donor inotropic support (p = 0.004), female donor (p = 0.04) and rejection at the time of the study ( p = 0.01). Forty-one patients were re-studied at follow-up. Nine of them (2 2%) presented endothelial dysfunction. Early endothelial dysfunction was re stored in 6 patients (43%) at follow-up. The number of episodes of rejectio n was the only variable associated to late endothelial dysfunction. Conclusions: Endothelial dysfunction is a common finding after cardiac tran splantation. The pathogenesis of this functional disturbance appears to be donor-related and immune-mediated, The reversibility of this phenomenon obs erved at follow-up suggests the episodic nature of the immunologic injury.