Key words : Combined heart and kidney transplantation, Dilated cardiomyopathy, End-stage renal disease, Heart transplantation, Kidney transplantation

Introduction

Combined heart and kidney transplant (CHKT) is a rare but valuable therapeutic option for selected patients with end-stage cardiac and renal failure. In appropriately selected recipients, CHKT has been associated with favorable long-term survival, a lower rejection risk, and acceptable graft outcomes. Chronic kidney disease in patients with an established indication for heart transplant represents a major comorbidity and may adversely affect outcomes if isolated heart transplant is performed. Published series have suggested that CHKT is a safe and effective strategy in selected recipients.^1-3 Herein, we present the 20-year follow-up of a patient who underwent CHKT for dilated cardiomyopathy and end-stage renal disease secondary to glomerulonephritis.

Case Report

A 27-year-old man with a history of pulmonary stenosis had undergone valvuloplasty in 1998. In 2003, he had been diagnosed with chronic kidney failure secondary to glomerulonephritis, and hemodialysis was initiated. During follow-up, he also developed progressive dilated cardiomyopathy. In 2005, his left ventricular ejection fraction had declined from 35% to 24%, and he had been hospitalized 3 times to treat acute pulmonary edema. Coronary angiography at that time had revealed normal coronary arteries, a pulmonary capillary wedge pressure of 16 mm Hg, a pulmonary artery pressure of 38/16 mm Hg, and a value of 1 for the ratio of pulmonary blood flow versus systemic blood flow.

As heart failure progressed, the patient had be-come intolerant to hemodialysis. Severe hypotension, marked pulmonary congestion on imaging, and inability to perform effective ultrafiltration were observed during dialysis sessions. Because of wor-sening heart failure and intolerance to hemodialysis, the patient was scheduled for CHKT.

In 2006, he underwent CHKT using organs from a 52-year-old deceased male donor. Cold ischemia time was 6.5 hours, and HLA matching was 3/6. Induction immunosuppression consisted of anti-thymocyte globulin. Maintenance immunosuppres-sion therapy included tacrolimus, mycophenolate mofetil, and prednisolone. At the end of the first posttransplant year, tacrolimus was replaced with sirolimus to minimize nephrotoxicity and to reduce the risk of cardiac allograft vasculopathy. No peri-operative complications occurred, and no infectious episode was recorded during follow-up.

For the 2006 CHKT surgery, the patient was extubated on postoperative day 1, transferred to the ward on postoperative day 4, and discharged on postoperative day 14. No rejection was detected on the predischarge endomyocardial biopsy. Echocardiog-raphy performed on postoperative day 14 demon-strated a left ventricular ejection fraction of 52%.

Long-term cardiac follow-up included serial echocardiography and endomyocardial biopsies. A total of 19 endomyocardial biopsies were performed during the 20-year follow-up period. Only 1 episode of early cardiac rejection had been detected, which was in the second posttransplant year and was successfully controlled by intensification of mycop-henolate mofetil therapy. Left ventricular ejection fraction had gradually declined in recent years, measuring 45%, 43%, 42%, 45%, and 40% during the last 5 years of follow-up, respectively; tricuspid annular plane systolic excursion was 15 mm at the most recent assessment (Figure 1).

Renal graft follow-up included serial laboratory analyses and Doppler ultrasonography. Early postoperative Doppler ultrasonography showed normal renal perfusion. Subsequent renal color Doppler ultrasonography demonstrated preserved blood flow and normal resistance index values. No episode of kidney allograft rejection occurred during follow-up, and kidney graft biopsy was not required. Serial serum creatinine values had remained relatively stable during long-term follow-up, with mild fluctuations and a gradual increase in recent years, measuring 1.28, 1.39, 1.25, 1.30, and 1.20 mg/dL, respectively, during the last 5 years of follow-up; the urine protein/creatinine ratio was 0.35 at the most recent assessment (Figure 2).

Discussion

Chronic kidney disease in candidates for heart transplant is an important determinant of postop-erative morbidity and mortality. In patients with advanced renal dysfunction, isolated heart transplant may not provide optimal long-term results; however, CHKT may offer better overall outcomes in selected recipients. Previous studies have demonstrated encouraging long-term survival after CHKT and have supported its safety and efficacy as a treatment strategy.^4-6

Weingarten and colleagues reported that long-term mortality in patients undergoing CHKT was lower versus selected patients undergoing isolated heart transplant.⁵ Similarly, analyses by Awad and colleagues⁶ and Ruzza and colleagues⁴ have shown that CHKT can be performed with acceptable long-term graft and patient outcomes. In this context, the present case is notable for very long-term survival after CHKT, with preserved renal graft function and limited cardiac rejection risk.

Another important aspect of our case is the stable renal graft course (Figure 3). No kidney allograft rejection occurred, kidney biopsy was never required, and renal function remained preserved at long-term follow-up. In addition, the cardiac course was favorable, with only 1 rejection episode during follow-up, which was successfully managed medically. The conversion from tacrolimus to sirolimus at the end of the first posttransplant year may also have contri-buted to long-term preservation of renal function and reduction of cardiac allograft vasculopathy risk.

The most remarkable feature of this case is the
20-year survival after CHKT, achieved without major perioperative complications, infectious episodes, or significant graft dysfunction. This finding supports the view that CHKT can provide durable long-term benefits in carefully selected patients when perfor-med within a multidisciplinary framework and followed by close long-term surveillance.

The limitations of this report are inherent to its design as a single case. Therefore, the findings cannot be generalized to all transplant recipients. Nevertheless, long-term case-based observations remain valuable in rare procedures such as CHKT, particularly when accompanied by extended follow-up data.

Conclusions

This case demonstrates that CHKT can provide durable long-term survival with preserved renal graft function and limited cardiac rejection risk in carefully selected patients. Our study also highlights the importance of multidisciplinary evaluation, individualized immunosuppressive management, and close long-term follow-up to achieve favorable outcomes after CHKT.

References:

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