Short-term angiopeptin therapy and the incidence of graft vessel disease after heart transplantation

Elevated uric acid levels predict allograft vasculopathy in cardiac transplant recipients

BACKGROUND

Cardiac allograft vasculopathy (CAV) poses the greatest threat to the long-term survival of cardiac transplant recipients, and these individuals often exhibit elevated levels of uric acid (UA), a stimulator of T cells. We hypothesized that hyperuricemia is associated with CAV in cardiac transplant recipients.

METHODS

UA levels were measured in cardiac transplant recipients between January 2003 and January 2005. Surveillance cardiac catheterizations performed 3 months to 1 year after UA measurement were reviewed. The relationship between UA and CAV was adjusted for possible confounders with propensity scores and confirmed with goodness-of-fit tests.

RESULTS

The 105 patients included in this study were a median 63.3 months post-transplant and their left heart catheterizations were performed a median 5.6 months after UA measurement. Focal stenosis was evident in 25 angiograms and 31 showed distal pruning of the coronary arteries. Compared with the lowest quartile of UA, the highest quartile had an increased risk of CAV: odds ratio (OR) 6.11 (95% CI 1.47 to 25.5; p = 0.013) for focal stenosis and OR 4.60 (95% CI 1.34 to 15.8; p = 0.015) for distal pruning. After adjustment, this relationship persisted for both focal stenosis (OR 5.53, 95% confidence interval [CI] 1.29 to 23.7; p = 0.021) and distal pruning (OR 4.21, 95% CI 1.15 to 15.4; p = 0.029).

CONCLUSIONS

Elevated UA confers an increased risk of CAV. This association may be causal, with pathophysiologic implications for the role of hyperuricemia in allograft failure and, if substantiated, could have clinical implications for the use of xanthine oxidase inhibitors in cardiac transplant recipients.

Effects of Growth Hormone Therapy in Children After Cardiac Transplantation

BACKGROUND

Growth hormone (GH) is used to treat growth failure in children with GH deficiency. The safety and efficacy of GH after pediatric cardiac transplantation is not known. The objective of this study was to evaluate growth and cardiovascular effects of GH in children with growth failure after cardiac transplantation.

METHODS

Pediatric cardiac transplant recipients who received GH from 1994 to 2004 were evaluated. Growth, cardiac function, hemodynamics and rejection frequency were serially monitored for 2 years before, during and after GH. Eight age-matched heart transplant recipients undergoing a natural growth spurt were evaluated as controls.

RESULTS

The mean age of subjects at initiation of GH was 13 +/- 3 years (mean duration 2.5 +/- 1 years, n = 10), of whom 3 were GH-deficient. Growth velocity (GV) increased from 2.5 +/- 2 to 8.6 +/- 3 cm/year with GH. There was an increase in left ventricular (LV) shortening fraction (SF; 37 +/- 1% to 41 +/- 1%), LV mass (93 +/- 11 to 118 +/- 15 g/m2), LV volume (138 +/- 14 to 188 +/- 21 ml/m2) and cardiac index (3.1 +/- 0.7 to 4.1 +/- 0.5 liters/min/m2) during GH therapy (p < 0.05). After discontinuation of GH, SF, cardiac index and LV mass returned to normal, but LV volume did not. In control patients, LV volume increased without an increase in SF or mass. Rejection frequency did not change in either group. There were no adverse events related to GH.

CONCLUSIONS

GH is safe and effective in treating growth failure in children after cardiac transplantation. GH therapy is associated with an increase in LV mass, volume and cardiac output. These changes are partially reversible after discontinuation of GH. The mechanisms and long-term consequences of these changes require further investigation.

Impact of Pre-Operative Diabetes Mellitus Upon Early and Late Survival After Heart Transplantation: A Possible Era Effect

BACKGROUND

The effect of pre- or post-operatively acquired diabetes mellitus on survival after heart transplantation remains controversial. The influence of transplant era on diabetes-associated survival is unknown.

METHODS

A retrospective database analysis was performed on all cardiac transplant recipients followed up at our institution between 1986 and 2003. Diabetes mellitus was diagnosed based on oral glucose tolerance testing.

RESULTS

Survival was analyzed in 243 patients (80% male, mean age 52.2 years, mean follow-up 5.22 years). Kaplan-Meier survival analysis demonstrated significantly worse (p = 0.0001) survival both early (months 0 to 12) and late (>5 years) after transplantation in pre-operative diabetics (n = 53) compared with non-diabetics (n = 190). Pre-operative diabetes was identified as the only independent risk factor for decreased long-term (>1 year) survival (p = 0.004). In contrast, no effect on survival (p = 0.5) was demonstrated in patients becoming diabetic only after heart transplantation (n = 39). At 12 months post-transplant renal function was significantly impaired in diabetics (p = 0.025); acute rejection, cytomegalovirus (CMV) infection and transplant vasculopathy occurred with similar frequency. Causes of death were similar in diabetics and non-diabetics. Reduced long-term survival in pre-operative diabetics was seen in the early transplant era (1986 to 1994) (p < 0.0001), but not in the more recent era (1995 to 2003) (p = 0.5).

CONCLUSIONS

Pre-transplant but not post-transplant diabetes confers an adverse risk for survival (short and long term). Diabetes-associated long-term survival appears to have improved in the recent era, supporting continued transplantation in diabetics under close surveillance and aggressive medical management.