22 Renal complications in LVAD and heart transplant patients

Renal dysfunction remains a primary determinant of both short- and long-term outcomes following heart transplantation (HTx) and ventricular assist device (VAD) implantation.1 2 Challenging to the assessment of candidacy for advanced heart failure (HF) therapies is the ability to distinguish intrinsic parenchymal renal disease from reversible cardiorenal disease. Patients with haemodynamically mediated renal failure may recover kidney function once renal perfusion is restored following HTx or VAD surgery. Chronic hypoperfusion, however, can lead to progressive structural lesions that may not improve despite correction of underlying haemodynamic abnormalities. In patients undergoing kidney biopsy as part of their HTx evaluation, there was poor correlation between eGFR and the extent of tubular atrophy and interstitial fibrosis.3 Prolonged elevation of serum creatinine (SCr) levels suggest but do not prove irreversibility and SCr in isolation is unlikely the best biomarker to determine transplant candidacy in this clinical setting. Reasons for SCr elevation in HF including pharmacotherapies such as renin-angiotensin-aldosterone system antagonists which lead to SCr elevations unrelated to underlying renal dysfunction. Additionally, patients with HF are frequently malnourished with muscle wasting, in which case SCr levels may be misleading. Baseline proteinuria is associated with poor post-operative outcomes in LVAD recipients and is an easily measurable biomarker that can further help to risk stratify patients in advance of VAD surgery.4 While absolute thresholds of risk are difficult to define, if eligible for dual organ transplant, advanced HF patients with GFR <35 mL/min/m2 are likely to derive a survival benefit from simultaneous heart-kidney transplantation rather than HTx alone.5 References Kirklin JK, Naftel DC, Pagani FD, Kormos RL, Stevenson LW, Blume ED, Miller MA, Baldwin JT, Young JB. Sixth INTERMACS annual report: a 10,000-patient database. J Heart Lung Transplant 2014;33:555–564. Erratum in: J Heart Lung Transplant2015;34:1356. Hong KN, Merlo A, Chauhan D, Davies RR, Iribarne A, Johnson E, Jeevanandam V, Russo MJ. Evidence supports severe renal insufficiency as a relative contraindication to heart transplantation. J Heart Lung Transplant 2016;35:893–900. Labban B, Arora N, Restaino S, Markowitz G, Valeri A, Radhakrishnan J. The role of kidney biopsy in heart transplant candidates with kidney disease. Transplantation 2010;89:887–893. Topkara VK, Garan AR, Fine B, Godier-Furnémont AF, Breskin A, Cagliostro B, Yuzefpolskaya M, Takeda K, Takayama H, Mancini DM, Naka Y, Colombo PC. Myocardial recovery in patients receiving contemporary left ventricular assist devices: results from the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS). Circ Heart Fail 2016;9. pii: e003157. Kilic A, Grimm JC, Whitman GJ, Shah AS, Mandal K, Conte JV, Sciortino CM. The survival benefit of simultaneous heart-kidney transplantation extends beyond dialysis-dependent patients. Ann Thorac Surg 2015;99:1321–1327.