Role of heart failure etiology on arterial wave reflection in heart transplant recipients: relation with C-reactive protein

Abstract

Aortic augmentation index (AIa), a measure of arterial pressure wave reflection related to central and peripheral arterial stiffness, is elevated in many heart transplant recipients. We investigated whether the increase in wave reflection observed in some heart transplant recipients is influenced by the etiology of antecedent heart failure and circulating pro-inflammatory proteins early in the post-transplantation period. Two months after heart transplantation, 20 heart transplant recipients underwent noninvasive measurement of aortic pressure and wave reflection properties and measurement of plasma pro-inflammatory proteins. AIa adjusted to a heart rate of 75 beats/min (AIaHR75) was higher in heart transplant recipients with ischemic (n = 12) compared with nonischemic (n = 8) heart failure (P < 0.01). Similarly, circulating C-reactive protein, a marker of systemic inflammation and an independent predictor of allograft vasculopathy and death in heart transplant recipients, was higher in heart transplant recipients with ischemic than with nonischemic heart failure (log-transformed, P < 0.05). Moreover, there was a significant relation between log C-reactive protein and AIaHR75 (r = 0.68, P < 0.05), augmented pressure (r = 0.60, P < 0.01), roundtrip time of the reflected wave to the peripheral reflecting sites and back (r = -0.62; P < 0.01), and left ventricular wasted energy (r = 0.55, P < 0.01). Multiple regression analysis revealed that log C-reactive protein explained 43% of the variance in AIaHR75 and the difference in AIaHR75 between groups was abolished when adjusted for log C-reactive protein. Heart transplant recipients with antecedent ischemic heart failure demonstrated increased AIaHR75 compared with nonischemic heart transplant recipients and AIaHR75 was associated with higher circulating C-reactive protein concentration. Whether elevated arterial wave reflection and associated systemic low-grade inflammation early after transplantation have clinical implications in ischemic heart transplant recipients requires further investigation.