Management of Immunosuppression and Antiviral Treatment before and after Heart Transplant for HIV-Associated Dilated Cardiomyopathy

Heart transplantation and human immunodeficiency virus-navigating drug-drug interactions: a case report

BACKGROUND

Antiretroviral therapy (ART) has led to a decline in human immunodeficiency virus (HIV)-related mortality, but comorbidities, including organ dysfunction, are increasingly the focus of care. Heart transplant (HT) is a very effective therapeutic strategy for end-stage heart failure (HF); however, clinicians may be hesitant due to concerns of complex drug-drug interactions (DDIs) between ART and HT immunosuppressive regimens and the potential impact of ART on long-term HT outcomes. In this report, we describe long-term (76-month) follow-up of a patient with HIV-positive status who underwent orthotopic HT with special emphasis on complex drug interactions.

CASE PRESENTATION

A 58-year-old man with HIV-1 developed ischemic cardiomyopathy, progressed to end-stage HF and underwent orthotopic HT. To avoid DDIs with planned immunosuppressive therapies, the ART regimen was modified to consist of lamivudine, tenofovir disoproxil fumarate, rilpivirine, and raltegravir. Following HT, the patient's immunosuppression consisted of tacrolimus and mycophenolate mofetil. He has had normal cardiac function and no opportunistic infections and was subsequently switched to tenofovir alafenamide, emtricitabine, and bictegravir in combination for convenience. Serial HIV-1 RNA blood levels were constantly below the limit of quantification, and his CD4 count remained above 200 cells/mm3 (30-35%). Several DDIs were identified and addressed; however, his long-term post-HT complications included one episode of asymptomatic acute cellular rejection, adenocarcinoma of the prostate, basal cell carcinoma, cardiac allograft vasculopathy, and peripheral neuropathy.

CONCLUSION

The clinical outcome of this case supports the conclusion of previously published reports, summarized here within, demonstrating that HIV-1 positive status should not preclude HT in carefully selected individuals. Both addressing potential DDIs prior to HT and long-term monitoring for routine post-transplant complications and secondary and incidental malignancies are imperative.

HIV-1-Associated Left Ventricular Cardiac Dysfunction in Humanized Mice

The molecular cause(s) for early onset heart failure in people living with HIV-1 infection (PLWH) remains poorly defined. Herein, longitudinal echocardiography was used to assess whether NOD.Cg-Prkdc^scid Il2rgt^m1Wjl/SzJ mice reconstituted with human hematopoietic stem cells (Hu-NSG mice) and infected with HIV-1_ADA can recapitulate the salient features of this progressive human disease. Four weeks post infection, Hu-NSG mice of both sexes developed left ventricular (LV) diastolic dysfunction (DD), with 25% exhibiting grade III/IV restrictive DD with mitral regurgitation. Increases in global longitudinal and circumferential strains and declines in LV ejection fraction and fractional shortening were observed eight weeks post infection. After twelve weeks of infection, 33% of Hu-NSG mice exhibited LV dyskinesia and dyssynchrony. Histopathological analyses of hearts seventeen weeks post infection revealed coronary microvascular leakage, fibrosis and immune cell infiltration into the myocardium. These data show for the first time that HIV-1_ADA-infected Hu-NSG mice can recapitulate key left ventricular cardiac deficits and pathophysiological changes reported in humans with progressive HIV-1 infection. The results also suggest that HIV-1 infected Hu-NSG mice may be a useful model to screen for pharmacological agents to blunt LV dysfunction and associated pathophysiologic causes reported in PLWH.

Heart health in the age of highly active antiretroviral therapy: a review of HIV cardiomyopathy

PURPOSE OF REVIEW

Advancements in highly active antiretroviral therapy (HAART) for human immunodeficiency virus (HIV) has led to increased survival, approaching that of the general population. These patients are at an increased risk for heart disease, specifically HIV-associated cardiomyopathy.

RECENT FINDINGS

Initially, HIV-associated cardiomyopathy was predominantly noted as systolic dysfunction, but diastolic dysfunction has become more common with increased use of HAART. The pathogenesis of HIV-associated cardiomyopathy involves direct viral infection, cytokine activity, focal myocarditis, HAART side effects, immune system dysregulation, and/or ischemia. If cardiomyopathy is diagnosed, an HIV patient should be started, or continued, on HAART and initiated on guideline-directed medical therapy (GDMT) per the ACC/AHA guidelines. The safety and efficacy of mechanical circulatory support and heart transplant in this population has been repeatedly demonstrated, but it remains less available compared with the general advanced heart failure population.

SUMMARY

The widespread use of HAART has led to prolonged survival in HIV patients to the point that cardiac disease has become the most common cause of death. Patients should be treated with HAART for HIV and GDMT for heart failure. Patients progressing to end-stage heart failure should be referred for advanced therapies to centers with experience treating HIV patients.

Interactions between anti-infective agents and immunosuppressants-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation provide an update on potential drug-drug interactions between anti-infectives and immunosuppressants, which are most notable with calcineurin and mTOR inhibitors. Drug-drug interactions may occur through pharmacokinetic mechanisms leading to altered drug concentrations of either the anti-infective or immunosuppressive drug, or by pharmacodynamic interactions increasing or decreasing the efficacy or toxicity of the medications. Many of the significant pharmacokinetic interactions occur through inhibition or induction of the cytochrome 3A4 system by anti-infective agents leading to increased or decreased immunosuppressive agent levels, respectively. The membrane transporter P-glycoprotein is also often involved in drug interactions. Since the last iteration of these guidelines, multiple new hepatitis C virus direct-acting antivirals have become available for use in SOT recipients. Of these agents, some are substrates of cytochrome and drug transporter systems, while others inhibit these systems and may affect immunosuppressive agents. Due to the high risk for drug-drug interactions in the solid organ transplant population, practitioners must be aware of potential interactions and be vigilant in monitoring and adjusting drug dosing when appropriate.

An Update on Heart Transplantation in Human Immunodeficiency Virus-Infected Patients

Cardiovascular diseases have become a significant cause of morbidity in patients with human immunodeficiency virus (HIV) infection. Heart transplantation (HT) is a well-established treatment of end-stage heart failure (ESHF) and is performed in selected HIV-infected patients in developed countries. Few data are available on the prognosis of HIV-infected patients undergoing HT in the era of combined antiretroviral therapy (cART) because current evidence is limited to small retrospective cohorts, case series, and case reports. Many HT centers consider HIV infection to be a contraindication for HT; however, in the era of cART, HT recipients with HIV infection seem to achieve satisfactory outcomes without developing HIV-related events. Consequently, selected HIV-infected patients with ESHF who are taking effective cART should be considered candidates for HT. The present review provides epidemiological data on ESHF in HIV-infected patients from all published experience on HT in HIV-infected patients since the beginning of the epidemic. The practical management of these patients is discussed, with emphasis on the challenging issues that must be addressed in the pretransplant (including HIV criteria) and posttransplant periods. Finally, proposals are made for future management and research priorities.