Increasing heart transplant donor pool by liberalization of size matching

https://doi.org/10.1016/j.healun.2019.08.020Get rights and content

BACKGROUND

The heart transplant (HT) guidelines recommendation to match recipient and donors within 30% of body weight lacks a strong evidence base and is not well established in patients bridged to transplant with left ventricular assist devices (LVAD). In light of the scarcity of donor hearts, we investigated the effect of size mismatch on hemodynamics, one-year survival and length of stay (LOS) following HT.

METHODS

Single-center retrospective analysis of consecutive HT patients from April 2007 to September 2017. Recipients were divided into 3 cohorts based on donor-to-recipient weight ratio (DRWR): (1) undersized (<0.7), (2) size-matched, (0.7–1.3); (3) oversized (>1.3).

RESULTS

288 consecutive patients were identified (mean age 53 ± 11 years; 76% male), 46 were undersized (0.61 ± 0.05), 210 size-matched (0.94 ± 0.16), and 32 oversized (1.65 ± 0.38). There was no significant difference in donor left ventricular end diastolic diameter (LVEDD) between the 3 groups (p = 0.11). The donor/recipient (D/R) predicted heart mass (PHM) was lowest in the undersized group (0.92 ± 0.13). There were no significant differences in 1-year survival in the overall and LVAD cohort (p = 0.65 and 0.59, respectively). Neither donor LVEDD nor D/R PHM differed among survivors or non-survivors. LOS was longer in the undersized group than the size-matched cohort (p = 0.004). The undersized group had hearts with the highest filling pressures and lowest cardiac index at 1 week among the remaining groups (p = 0.009, 0.017, and p = 0.05, respectively). There were no clinically significant differences in hemodynamics at 1 or 6 months.

CONCLUSIONS

HT undersizing affects hemodynamics early but not later in the course and does not impact 1-year survival. The liberalization of size matching may increase the HT donor pool significantly.

Section snippets

Study design

We performed a retrospective chart analysis of consecutive patients undergoing HT at the University of Chicago between April 2007 and September 2017. The University of Chicago Institutional Review Board approved this retrospective chart review. Heart allocation at the University of Chicago incorporates LVEDD matching and does not exclude donor hearts solely based on weight matching criteria. Pre-transplant donor information, including height, weight, and echocardiographic data, were retrieved

Patient characteristics

Two hundred eighty-eight consecutive patients comprised the study cohort. The mean age was 53 ± 11 years, and 76% were males (Table 1). Out of the 288 patients, 58 were bridged to transplantation with LVAD.

Based on DRWR, 46 (16%) patients were in the undersized group (0.61 ± 0.05), 210 (73%) patients were in the size-matched group (0.94 ± 0.16), and 32 (11.1%) patients were in the oversized group (1.65 ± 0.38).

There were no significant differences in demographics, gender mismatch,

Discussion

In the current study, we evaluated the effect of D/R heart size matching on survival and hemodynamics. Our main findings are as follows: (1) Recipients of donor hearts that are undersized according to DRWR have a statistically comparable outcome to recipients of size-matched or oversized hearts. (2) Recipients of donor hearts that are undersized according to DRWR have higher intracardiac filling pressures and lower CI early after transplantation, but the hemodynamic differences resolve with

Disclosure statement

The authors have no conflicts of interest to disclose.

References (28)

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