Preoperative Evaluation Improves the Outcome in Heart Transplant Recipients With Pulmonary Hypertension-Retrospective Analysis of 106 Cases

Selecting oversized donor cardiac allografts for patients with pulmonary hypertension may be unnecessary

INTRODUCTION

There is a tendency to favor oversized donor hearts for heart transplant candidates affected by mild to moderate pulmonary hypertension (PHTN). We hypothesize that both undersized and oversized donor hearts fare equally well in this setting.

METHODS

A total of 107 cases from 2003 to 2008 were retrospectively reviewed and subsequently divided into those receiving organs from undersized donors (group 1: donor weight/recipient weight ≤ 0.90, n = 37) and oversized donors (group 2: donor weight/recipient weight ≥ 1.2, n = 70). PHTN was identified in the perioperative period in those patients with systolic pulmonary artery pressure (SPAP) ≥ 40 mm Hg. Endpoints of mortality and hemodynamic data were investigated.

RESULTS

Of 107 patients, 37 received undersized donor allografts, with a mean donor-to-recipient weight ratio of 0.8, and 70 received oversized donors allografts, with a mean donor-to-recipient ratio of 1.4. Perioperative PAH was diagnosed in 20 of the 37 (54%) patients from the undersized group (mean SPAP = 45.9 mm Hg) and 41 of 70 (59%) patients from the oversized group (mean SPAP = 46.5 mm Hg). There was no significant difference in right ventricular function at 1 week, 1 month, or 6 months. Left ventricular function was similar between both groups at 6 months (P = .22). The mean SPAP in the undersized group was 45.9, 33.4, 31.8, and 23.1 mm Hg at the perioperative, 1 week, 1 month, and 6 month time points, respectively. Corresponding mean SPAP for the oversized group was 46.5, 35.0, 29.4, and 26.1 mm Hg. The 1 month, 1 year, and 3 year survivals were similar in both groups.

CONCLUSIONS

Oversized and undersized donor hearts fared equally well in the setting of mild to moderate perioperative PAH. This in addition to the propensity for resolution of pulmonary hypertension over time suggests that the current practice of favoring oversized donor hearts for patients with pre-transplantation PAH may be unwarranted.

Inhaled nitric oxide versus sodium nitroprusside for preoperative evaluation of pulmonary hypertension in heart transplant candidates

OBJECTIVE

The development of pulmonary hypertension before heart transplantation increases the risk for postoperative right ventricular failure. Reversibility of pulmonary vascular resistance (PVR), which indicates the feasibility of heart transplantation, can be tested with the use of intravenous vasodilators, such as sodium nitroprusside (NaNTP) or prostacyclin. However, the drawback of these drugs is the development of systemic hypotension. The aim of this study was to evaluate the safely and feasibility of inhaled nitric oxide (iNO) compared with sodium nitroprusside to test PVR reversibility, while avoiding systemic hypotension.

MATERIALS AND METHODS

We included all patients who were affected by end stage heart failure undergoing evaluation for heart transplantation if they showed elevated PVR > 2.5 Wood units and mean pulmonary arterial pressure (mPAP) >25 mm Hg. The hemodynamic parameters measured by right heart catheterization were: systolic blood pressure (SBP), mPAP, pulmonary capillary wedge pressure, and cardiac index (CI). The following variables were derived: transpulmonary gradient (TPG) and PVR. All patients were tested by both iNO (20-40 ppm) and intravenous NaNTP, at increasing dosages which were titrated based on systemic pressure. We randomly assigned the order of administration of iNO and NaNTP.

RESULTS

The 9 male candidates has an average age of 56 ± 4 years. Seven of the 9 (71%) had postischemic cardiomyopathy, and 2 had idiopathic cardiomyopathy. We observed a reduction of mPAP (32% and 14%), PVR (41% and 32%), TPG (20% and 26%), and SBP (17% and 5%) and an increase of CI with administration of NaNTP and iNO, respectively.

CONCLUSIONS

We observed a reduction in PVR and mPAP with administration of either iNO and NaNTP. A better effect of NaNTP was attributed to reducted post-load of the left ventricle. However, the main advantage of iNO was the absence of systemic hypotension and its selectivity for pulmonary vascular system, as underscored by TPG reduction.

Impact of pulmonary hypertension on transplant outcomes in pediatric cardiomyopathy patients

Controversy exists over whether PHTN in heart transplant candidates increases post-transplant mortality. We performed analysis of data reported to UNOS for children who underwent primary heart transplantation for cardiomyopathy from January 1994 to June 2010. Patients were divided into two groups depending on their pre-transplant TPG: no-PHTN (TPG ≤ 12 mmHg) and PHTN (TPG >12 mm Hg). A total of 6139 children underwent transplantation of whom 2456 (40%) were for cardiomyopathies; 1322 (54%) of these had catheterization data available. The PHTN group (mean TPG 19.5 ± 8.6) had 312 patients and no-PHTN (TPG 6.7 ± 4.0) had 1010. Mortality at one month (4.5% vs. 2.3%) and three months (6.1% vs. 3.1%) post-transplant was significantly higher in the PHTN than the no-PHTN group with an odds ratio of 2 (p < 0.05). There was no significant effect of PHTN on early mortality in children <1 yr age. There was no significant improvement in early survival for transplants performed after compared to before 2003 in patients with PHTN despite availability of pulmonary dilators. Pre-transplant PHTN increases early post-transplant mortality in pediatric cardiomyopathy patients above one yr of age. There has been no significant improvement in the outcome of this group over the last seven yr.