Diaphragmatic hernias are a known complication of explanting a left ventricular assist device. The increasing use of left ventricular assist devices has resulted in an increased risk of this complication. We present the case of a patient who presented with diaphragmatic hernias on routine follow-up after a heart transplant. A left thoracotomy was performed to expose and reduce the hernia using a bovine pericardial patch to repair the defect. This biomaterial represents a viable alternative to traditional GORE-TEX patches with the probability of decreased infectious complications.

Key words : Diaphragm, Devices, Surgical complications

Case Report

At our institution, a 60-year-old man underwent a successful orthotropic heart transplant, secondary to ischemic heart failure. He was bridged with a HeartMate II Left Ventricular Assist System (Thoratec Corporation, Pleasanton, CA, USA) for 2 years before an organ became available. He had undergone a previous laparotomy, with a colon resection for ischemic colitis.

The patient’s postoperative recovery was uneventful, and was discharged home 12 days after having his operation. He returned for a scheduled, outpatient endomyocardial biopsy complaining of shortness of breath, increased fatigue, and intermittent epigastric abdominal pain. Subsequent fluoroscopy during his biopsy was performed concerning possible abdominal contents in his chest.

An expeditious computed topography scan confirmed the presence of a large diaphragmatic hernia (DH), with multiple loops of the bowel in his thoracic cavity (Figure 1). Of note, immunosuppression therapy, at that time, consisted of tacrolimus, mycophenolate mofetil, and prednisone.

He was taken to the operating suite to reduce the abdominal contents and repair his diaphragmatic defect. A seventh intercostal space left thoracotomy was done, providing adequate exposure of the hernia and facilitating reduction of the contents. At the time of the transplant, the diaphragmatic defect had been reapproximated with 0 monofilament absorbable sutures. After reducing the hernia, it was obvious that the sutures had pulled through the diaphragmatic tissue. Given the failure of the previous repair and the patient’s immunosuppressed status, the defect was closed using a bovine pericardium patch (Figure 2). His postoperative hospital course was unremarkable. The patient was discharged on postoperative day 8 on regular diet, no longer complaining of shortness of breath, abdominal pain, or fatigue.

Discussion

Diaphragmatic hernias are a well described and increasingly common postoperative complication of a heart transplant after explanting a left ventricular assist device.¹ In no small part is this due to the splitting of the diaphragm to implant the left ventricular assist device. Often, the poor nutritional status, combined with the requirement for immuno­suppression in the patient, increases the likelihood of primary diaphragm repair failure. Contemporary studies estimate the incidence of DHs at upwards of 15.9%.² Furthermore, upwards of 30% of patients undergoing a heart transplant have had a prior left ventricular assist device, and this percentage is likely to become increased.³ As a result, the incidence of posttransplant DHs is likely to become a significant concern.

Health care providers managing this subset of patients must have an increased awareness of this entity as a diagnostic possibility. Suspicion must be raised in individual who complains of shortness of breath or abdominal pain postoperatively. Surgical repair of these defects is recommended upon their diagnosis, as they can lead to bowel strangulation, incarceration, necrosis, and perforation.⁴ Surgical principles of tension-free repair should be followed, and synthetic materials (eg, polytetrafluoroethylene and polypropylene) have been used successfully for this.² The transplanted population, however, deserves special attention with reduction of potential long-term infectious complications. The use of an immunologically inert, biological material has certain advantages for this.

The use of a bovine pericardium has been previously evaluated by Zardo and associates who used it for chest wall reconstruction and diaphragmatic defect repairs secondary to tumor resection.⁵ It demonstrated high tensile strength, elasticity, and was easy to manipulate. The patch has good biocompatibility, allowing ingrowth of natural tissue and minimal risk of infection.⁵ These qualities, combined with the possibility of microtears in a reoperative setting, prompted the selection of a bovine pericardium to repair the DH in this patient. Although the long-term outcomes remain uncertain, this case demonstrates the successful use of a bovine pericardium to repair a DH. This material and technique should be in the armamentarium of the thoracic transplant surgeon as a viable alternative to using synthetic mesh in immunocompromised patients.

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