EXPERIMENTAL AND CLINICAL TRANSPLANTATION

Organ transplant from donors with ventricular assist devices is not common. Here, we report organ retrieval from a donor with a left ventricular assist device who had been on the heart transplant wait list before a brain death diagnosis. The organ donor was diagnosed with dilated cardiomyopathy and underwent left ventricular assist device surgery for bridging to heart transplant in 2016. Brain death occurred 22 months after implantation of the device at the age of 39 years due to widespread intraparenchymal and subarachnoid hemorrhage. Brain death diagnosis was confirmed with brain perfusion single-photon emission computed tomography. In accordance with the donor’s will, the relatives approved organ donation. The donor’s organ reserve was assessed to be suitable for liver and kidney transplants, and proper donor care was given. During recovery of organs, the organ transplant team was accompanied by cardiovascular surgeons to control flow of the left ventricular assist device and to ensure optimum organ perfusion. After a successful operation, the liver was transplanted to a patient with primary sclerosing cholangitis who had been on the wait list for liver transplant for 13 years. The kidneys were transplanted to patients awaiting kidney transplant for 31 and 14 years with diagnoses of nephrolithiasis and polycystic kidney disease, respectively. No complications occurred among the liver and kidney transplant recipients. There are few reports of donors with assist devices. This is the first case of an organ donor with an assist device waiting for an organ transplant who became an actual donor in our country.

Key words : Deceased donor, Extended criteria donor, Heart failure

Heart failure is a pathologic condition in which the heart cannot pump blood to the tissues in the appropriate amount for its metabolic needs or can only achieve the appropriate amount with high cardiac filling pressures. More than 2 million people in our country live with heart failure.¹ In patients with insufficient medical treatment, mechanical circulatory support devices are implanted. Heart transplant is the main treatment method in patients with end-stage heart failure when all other treatment modalities are insufficient. Ventricular assist devices (VADs) are frequently used in this patient group due to the limited number of donors and due to some conditions that constitute contraindications to transplant (such as pulmonary hypertension). These devices are used as a bridge to transplant, as a bridge to recovery, or as a destination therapy. Reports have shown that survival rates have increased in patients with end-stage heart failure in recent years.^2-4

The transplant of organs from donors with VADs are not common in the literature due to the limited number of VAD donors and the fact that the grafts from these patients are not first choice.⁵ Here, we report successful organ retrieval from a donor with a left ventricular assist device (LVAD) who was on the heart transplant wait list before brain death diagnosis.

A 37-year-old male patient was admitted to our center in 2016 with a diagnosis of ischemic cardiomyopathy. Because the patient was unresponsive to medical treatment, an LVAD (HeartWare Ventricular Assist Device System, HeartWare, Framingham, MA, USA) was implanted and tricuspid valvuloplasty with 4-vessel coronary artery bypass grafting was applied on day 4 of hospitalization as a bridge to heart transplant. After a successful postoperative follow-up, the patient was discharged from the hospital. The patient had regular control visits to monitor the LVAD, and drug doses were regulated postoperatively. The patient, who was on a wait list for heart transplant, was admitted to the intensive care unit (ICU) due to diffuse intraparenchymal hemorrhage and subdural hematoma 22 months after LVAD implantation. At the ICU admission, the patient’s Glasgow coma score was 3 and the Acute Physiology and Chronic Health Evaluation II severity score was 24. Neurosurgical consultation revealed that the patient was unsuitable for surgical treatment as the patient’s international normalized ratio was 7 and because massive intracerebral hemorrhage was seen on computed tomography images (Figure 1). Medical therapy included mannitol 6 × 100 mg, decort 4 × 4 mg for antiedemic treatment, and levetiracetam 2 × 250 mg for antiepileptic treatment. No spontaneous breathing was observed at hour 7 of ICU admission. The patient was still unconscious with Glasgow coma score of 3 while mechanically ventilated.

During neurologic examination, due to the absence of brainstem reflexes, the patient was evaluated for brain death diagnosis. The cause of this irreversible brain damage was determined as massive intracerebral hemorrhage. Potential reversible causes of coma, including effects of sedatives, anesthesia, analgesics, and neuromuscular blockers or similar drugs that could affect the level of consciousness, were excluded.⁶ Laboratory tests confirmed that no electrolyte imbalances and/or metabolic disorders were present that led to the absence of brainstem reflexes. Blood pressure levels were within normal limits, and central body temperature was above 36°C. The patient, who met the above-mentioned preconditions for brain death, then underwent an apnea test. Initial arterial blood gas analyses with 100% fraction of inspired oxygen showed pH level of 7.47, partial pressure of CO₂ of 30.9 mm Hg, and partial pressure of O₂ of 155 mm Hg.

The patient was disconnected from the ventilator, which had T-tube level of 6 L/min of O₂. The patient’s apnea test was considered as positive for brain death due to the following measurements of arterial blood gas at minute 20 after disconnection: pH level of 7.16, partial pressure of CO₂ of 66.1 mm Hg, and partial pressure of O2 of 98.6 mm Hg.

Brain perfusion single-photon emission computed tomography imaging (Tc-99m HMPAO) was performed as a confirmatory test, which was consistent with brain death and reported as follows: “no flow of medium and anterior cerebral arteries were observed in the blood imaging, and venous sinuses could not be visualized in blood pool imaging” (Figure 2).

As a result of clinical examination and radiologic imaging, the 39-year-old patient was diagnosed with brain death at hour 36 after ICU admission. A neurosurgery specialist and an intensive care specialist diagnosed the brain death together in accordance with the 11th article of amended legislation of 2238 Organ Transplantation Law in 2014 in Turkey, which states the following: “Brain death is diagnosed unanimously by two physicians, one of whom is a neurologist or neurosurgeon and one is an anesthesiology and reanimation or intensive care specialist in accordance with the rules of evidence-based medicine.”

The organ procurement organization of our hospital was informed of the potential donor. The organ procurement organization representatives met with the relatives of the potential donor to authorize donation. The relatives of the patient, who stated that the patient wanted his organs to be donated while he was healthy, approved the organ donation, and preparations were made for organ retrieval. The organ reserve of the donor was considered suitable for liver, kidney, and corneal transplant, and medical treatments required for appropriate donor care were initiated. After the diagnosis of brain death, proper donor management was performed by the intensivist. Mannitol treatment for brain edema was terminated. Urinary output was closely monitored because of the diabetes insipidus risk due to pituitary failure after brain death. Desmopressin was not required as the diuresis of the patient was shown to be from 100 to 200 cm³/h. Sufficient fluid resuscitation was achieved, and infusion of 1 to 10 μg/kg/min of dopamine was started according to arterial blood pressure. Levotiron was added to the treatment for thyroid hormone replacement. The donor received infusion of 1 to 10 IU/h insulin, and normoglycemia (100-180 mg/dL) was maintained. Methylprednisolone infusion (10 mg/kg/24 h) was also started.

During retrieval of organs, the organ transplant team was accompanied by a team from the cardiovascular surgery department to monitor the donor’s LVAD and to ensure that adequate organ perfusion was achieved. Because the donor was a heart-beating donor, particular attention was paid not to damage the LVAD system during donor surgery.

After successful organ retrieval, the liver was transplanted to a patient with primary sclerosing cholangitis who had been on a liver transplant wait list for 13 years. The kidneys were transplanted to patients who were on kidney transplant wait lists for 31 and 14 years with diagnoses of nephrolithiasis and polycystic kidney disease, respectively. No complications occurred among the liver and kidney transplant recipients postoperatively.

The number of donors with VADs is quite low in the literature. Although low in numbers, there are cases of successful kidney, liver, and lung transplant procedures from donors who have LVADs.^5,7,8 This case is the first in our country reporting such a donor, who had received an LVAD for the purpose of bridging to heart transplant but eventually became an organ donor.

Patients with VADs are not the first choice for organ donations because there are difficulties due to the running assist device during the thoracotomy and laparotomy. In addition, there may be possible damage to grafts due to the donor’s chronic heart failure (or fibrosis, etc), the donor’s need for continuous anticoagulation, the risk of embolism, and the possibility of organ damage during cardiogenic shock.⁹ However, shortages of organs continue to be one of the main limitations in organ transplantation. Therefore, organs retrieved from patients with VADs can be used to expand the donor pool.

The number of deceased organ donors in Turkey is quite low. When we compare the number of organ transplants performed versus the number of patients on transplant wait lists, the inadequacy can be clearly seen. Although there are 25 908 patients on organ transplant wait lists in Turkey, according to official data, in 2017, only 4908 transplant surgeries could be performed.¹⁰The measure of organ donors in a country is shown by the organ donor per million population. According to data from the Turkish Transplant Foundation, in 2018, deceased-donor organ recovery was 7.3 per million population. Although 2174 patients with brain death were reported in 2018, only 598 (27%) were approved for organ transplant. When we consider the insufficient number of grafts for patients on organ transplant wait lists, the evaluation of patients with VADs as organ donors should be accepted as a necessity today.

With the small number of organ donors in our country, patients with mechanical circulatory support devices, despite their technical difficulties, should be accepted as donors in order to expand the donor pool. With the consideration that the grafts retrieved from the patient described in this case report were transplanted successfully to 3 people waiting for organ transplant, we suggest that patients with VADs should be more often evaluated as organ donors.

Volume: 19 Issue: 5 May 2021

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