Heart retransplant recipients with renal dysfunction benefit from simultaneous heart-kidney transplantation

Kidney function assessment using cystatin C and serum creatinine in heart transplantation recipients: Implications for valganciclovir dosing

BACKGROUND

Among heart transplantation (HT) recipients, the accuracy of serum creatinine (sCr)-based estimated glomerular filtration rate (eGFR) may be limited by fluctuations in muscle mass. Cystatin C (cysC) is less influenced by muscle mass, but its levels may increase with obesity and steroid use. Herein, we (1) longitudinally compared eGFRcysC and eGFRsCr among HT recipients; (2) investigated the association of body mass index (BMI), steroid use, and muscle mass with discrepancies between eGFRs; and (3) explored the implications of eGFRcysC use on valganciclovir (VGC) dosing.

METHODS

cysC and sCr were measured in 294 blood samples obtained from 80 subjects. Intraindividual differences between eGFRs (eGFRdiffcysC-sCr) were calculated with negative values corresponding to eGFRsCr > eGFRcysC and positive values to eGFRcysC > eGFRsCr. In a patient subset (n = 21), pectoralis muscle measures were obtained.

RESULTS

Marked differences between eGFRcysC and eGFRsCr were observed, particularly early post-HT (1-week post-HT, median eGFRdiffcysC-sCr -28 ml/min/1.73 m2). eGFRcysC demonstrated stability following a transient postoperative decline, while eGFRsCr decreased in the first year post-HT. Lower BMI and higher prednisone dose displayed a modest association with more negative eGFRdiffcysC-sCr values. Pectoralis muscle measures indicative of greater muscle mass and better tissue quality exhibited a stronger association with more positive eGFRdiffcysC-sCr values. The use of eGFRcysC would have led to VGC dose adjustment in 46% of samples, predominantly resulting in dose reduction.

CONCLUSIONS

Among HT recipients, eGFRcysC and eGFRsCr markedly differ with implications for VGC dosing. The observed discrepancies may reflect changes in body composition and steroid use.

Year in Review 2023: Noteworthy Literature in Cardiothoracic Transplantation

This review highlights key studies examining perioperative management of cardiothoracic transplantation published in 2023. Articles were manually screened after searching Scopus, PubMed, and Google Scholar databases for manuscripts related to cardiothoracic transplantation, which yielded 343 papers with 15 qualitatively selected as the most salient for readers. Overarching themes include differences in outcomes across the various etiologies of end-stage lung disease, novel developments to expand the donor pool, and multi-organ transplantation.

Evolutions in Combined Heart-Kidney Transplant

PURPOSE OF REVIEW

This review describes management practices, outcomes, and allocation policies in candidates for simultaneous heart-kidney transplantation (SHKT).

RECENT FINDINGS

In patients with heart failure and concomitant kidney disease, SHKT confers a survival advantage over heart transplantation (HT) alone in patients with dialysis dependence or an estimated glomerular filtration rate (eGFR) < 40 mL/min/1.73 m2. However, when compared to kidney transplantation (KT) alone, SHKT is associated with worse patient and kidney allograft survival. In September 2023, the United Network of Organ Sharing adopted a new organ allocation policy, with strict eligibility criteria for SHKT and a safety net for patients requiring KT after HT alone. While the impact of the policy change on SHKT outcomes remains to be seen, strategies to prevent and slow development of kidney disease in patients with heart failure and to prevent kidney dysfunction after HT and SHKT are necessary.