Abstract 17876: Microvasculopathy Preceeds and Predicts Epicardial Allograft Vasculopathy in Heart Transplant Patients
Background: Cardiac allograft vasculopathy (CAV) is the leading cause of late mortality after heart transplantation (HT). CAV affects both epicardial coronary vessels and microvasculature. We aimed to assess either the presence or the risk of CAV and severe microvascular dysfunction in relationship with time from heart transplantation (HT) and the validity of coronary flow reserve (CFR) as a predictor of CAV onset.
Methods: CFR was assessed in the left anterior descending coronary artery by transthoracic echocardiography in 120 HT pts (97 male, aged 50 ± 12 years at HT), at 9 ± 6 years post-HT. CAV was defined as any angiographic lesion ≥10%. Microvascular dysfunction was defined as CFR <2.5. The relationship between time from HT and CAV or microvascular dysfunction was evaluated by logistic regression. To evaluate CAV new onset coronary angiography was repeated after 3.6 ± 1.2 years.
Results: CAV was diagnosed in 75 pts (62%) (group A), 45 (38%) had no CAV (group B). Group A had lower CFR than group B (2.2 ± 0.6 vs 3.1 ± 0.7, p<0.0001). In 15 pts (33%) without CAV CFR was <2.5. At 5, 10 and 15 years from HT the probability of CFR<2.5 resulted higher than CAV probability (p<0.0001 for all comparisons) (Figure). In addition, a close correlation was observed between the presence of CAV and the evidence of CFR< 2.5 (χ2=21, OR 6.4, p <0.0001). CFR was lower in pts with CAV onset (3.4 ± 0.5 vs 2.6 ± 0.8, p=0.002). A CFR<2.5 was 100% specific and 60% sensitive for predicting CAV onset, (PPV= 100%, NPV=61%, Accuracy 76%) (p<0.0001). Pts with CFR<2.5 had a lower survival free from CAV onset (38% vs 100%, p<0.0001) (Figure). By Cox regression a CFR<2.5 predicted CAV onset (RR 6.3, 95% CI 2.5–15.6, p<0.0001).
Conclusions: In HT patients the risk of CAV and microvascular dysfunction increases with time from HT. The risk of severe microvascular dysfunction is higher than that of CAV. Finally, lower CFR is a reliable predictor of CAV onset.
- Transplantation/medical aspects
- Coronary microcirculation
- Follow-up studies
- Cardiovascular imaging
- © 2010 by American Heart Association, Inc.