Pretransplant risk factors of early mortality after orthotopic heart transplantation

Left ventricular assist devices decrease fixed pulmonary hypertension in cardiac transplant candidates

OBJECTIVE

Fixed pulmonary hypertension is a contraindication for cardiac transplantation because of the increased risk of donor heart failure. We sought to determine whether left ventricular assist devices improve fixed pulmonary hypertension in cardiac transplant candidates to enable safe cardiac transplantation.

METHODS

Thirty-five consecutive cardiac transplant candidates (age 56 +/- 6 years, 88.5% were men) with fixed pulmonary hypertension (5.1 +/- 2.6 Wood units) resistant to medical treatment received a left ventricular assist device as a bridge to transplantation. Three left ventricular assist device systems were used (pulsatile blood flow: Novacor [World Heart Inc, Oakland, Calif] n = 8; continuous blood flow: MicroMed DeBakey [MicroMed Technology Inc, Houston, Tex] n = 24, DuraHeart [Terumo Heart Inc, Ann Arbor, Mich] n = 3). Right-sided heart catheter data were obtained before left ventricular assist device implantation at 3-day and 6-week follow-ups. Clinical data and complications were recorded.

RESULTS

Before left ventricular assist device implantation, the pulmonary vascular resistance was 5.1 +/- 2.8 Wood units. Values were comparable in patients receiving pulsatile (5.1 +/- 3.4 Wood units) or continuous blood flow left ventricular assist devices (5.1 +/- 2.7 Wood units, P = .976). Left ventricular assist device implantation decreased pulmonary vascular resistance at 3-day (2.9 +/- 1.3 Wood units, P < .0001) and 6-week (2.0 +/- 0.8 Wood units, P < .0001) follow-ups compared with before implantation. This effect was independent of the type of left ventricular assist device system used (3-day follow-up: pulsatile flow: 3.2 +/- 1.3 Wood units vs continuous flow: 2.7 +/- 1.2 Wood units; P = .310 and 6-week follow-up: pulsatile flow: 1.9 +/- 0.9 Wood units vs continuous flow: 2.1 +/- 0.8 Wood units; P = .905). Twenty-four patients had successful bridges to transplantation (69%, mean time on left ventricular assist device 210 +/- 83 days), and 11 patients died before transplantation (31%, mean time on left ventricular assist device 67 +/- 30 days). The 1-year survival after transplantation was 95%.

CONCLUSION

Left ventricular assist devices decrease fixed pulmonary hypertension in cardiac transplant candidates and allow patients to overcome a contraindication for cardiac transplantation. Therefore, left ventricular assist devices should be considered in all cardiac transplant candidates with fixed pulmonary hypertension.

Association of parental pretransplant psychosocial assessment with post-transplant morbidity in pediatric heart transplant recipients

Because parents assume the primary responsibility for providing ambulatory post-transplant care to pediatric patients, pretransplant psychosocial evaluation in these recipients is usually focused on parents rather than on patients themselves. We sought to determine whether pretransplant parental psychosocial evaluation predicts post-transplant medical outcome at current levels of psychosocial support. We compared relative risk (RR) of rejection and hospitalizations (days of all-cause hospitalization) following initial discharge in patients in 'risk' and 'control' groups defined by their pretransplant parental psychosocial evaluation. We also compared the two groups of patients for the proportion of all outpatient trough cyclosporine A (CSA) or tacrolimus (FK) levels that were < 50% of the target level (defined as the mid-therapeutic range level). There were seven patients in the 'risk' group with a median age 0.25 yr (range 0.19-14.7 yr) and total follow up 20.5 patient-yr. There were 21 patients in the 'control' groups with a median age of 2.1 yr (range 0.05-16.2 yr) and total follow up of 71.3 patient-yr. There was no significant difference between the groups in rejection-risk or days of all-cause hospitalization early after transplant (first six months). During the late period (after the first six months), there were 11 rejection episodes in the 'risk' group over 17.4 patient-yr and four rejection episodes in control group over 61.8 patient-yr of follow up. After adjustment for age and race, patients in the 'risk' category had a RR of 3.4 for developing a rejection episode (p = 0.06) and 3.1 for being inpatient (p < 0.001) during the late period. Patients in the risk group were 2.9 times more likely to have subtherapeutic trough levels (< 50% target level) of calcineurin inhibitor (CSA or FK) during both early and late periods (p < 0.01 for both periods) after adjustment for patient age and race. We conclude that pretransplant parental psychosocial risk assessment is associated with post-transplant morbidity in children after cardiac transplantation. These patients may benefit from closer outpatient monitoring and a higher level of psychosocial support.

Recipient selection in cardiac transplantation: contraindications and risk factors for mortality

Currently the only acknowledged, definitive treatment for refractory heart failure is heart transplantation (HTx). During the past 10 years, selection criteria for heart transplant recipients have been developed that use an analysis of risk factors associated with mortality, which were identified by consensus opinion and by single-center and multi-center database review. A number of other studies also have been designed to evaluate specific risk factors for transplant such as advanced age, diabetes, and sex. This review identifies variables that continue to provoke controversy during the candidate selection process or variables that have changed from absolute to relative contraindications for HTx. Clinicians may use the data summarized in this review as a guide to making decisions about patient candidacy for HTx. One could conclude from this analysis that a more formalized and objective scale to select patients and to assess risk of death after HTx is necessary. Moreover, as alternative therapies to HTx become reality, a better instrument for triaging patients to one form of therapy or another may be necessary.