Reversible myocardial hypertrophy induced by tacrolimus in a pediatric heart transplant recipient: case report

Cardiovascular effects of immunosuppression agents

Immunosuppressive medications are widely used to treat patients with neoplasms, autoimmune conditions and solid organ transplants. Key drug classes, namely calcineurin inhibitors, mammalian target of rapamycin (mTOR) inhibitors, and purine synthesis inhibitors, have direct effects on the structure and function of the heart and vascular system. In the heart, immunosuppressive agents modulate cardiac hypertrophy, mitochondrial function, and arrhythmia risk, while in vasculature, they influence vessel remodeling, circulating lipids, and blood pressure. The aim of this review is to present the preclinical and clinical literature examining the cardiovascular effects of immunosuppressive agents, with a specific focus on cyclosporine, tacrolimus, sirolimus, everolimus, mycophenolate, and azathioprine.

Blood concentration of tacrolimus and age predict tacrolimus-induced left ventricular dysfunction after bone marrow transplantation in adults

PURPOSE

Tacrolimus (TAC) is used for the prophylaxis and treatment of acute graft-versus-host disease after bone marrow transplantation (BMT). However, few have reported on TAC-induced left ventricular hypertrophy. This study aimed to assess the relationship between blood concentration of TAC and development of TAC-induced left ventricular (TI-LV) dysfunction in adult BMT patients with hematologic malignant diseases, and to evaluate whether TAC concentration can predict TI-LV dysfunction occurrence in these patients.

METHODS

We enrolled 16 consecutive patients (mean age 44.6 ± 13.0 years) who received TAC after BMT. Echocardiography was performed before and after BMT, and blood concentrations of TAC were evaluated in terms of AUC₁₅ (area sum of TAC > 15 ng/ml during follow-up). We assessed the relationship between AUC₁₅ and development of TI-LV dysfunction after TAC.

RESULTS

During the follow-up period (mean duration 47.6 ± 13.7 days), interventricular septum thickness (IVST, P = 0.001) and posterior wall thickness (PWT, P < 0.001) increased, and E' decreased (P = 0.006). AUC₁₅ was associated with post-IVST (R = 0.627, P = 0.009), post-PWT (R = 0.669, P = 0.005), and post-E' (R = - 0.767, P = 0.001). In multivariate analysis, AUC₁₅ and age independently predicted the increase in IVST and PWT and decrease in E' after BMT. The combination of AUC₁₅ and older age predicted post-PWT with a sensitivity of 77.8% and specificity of 71.4%.

CONCLUSION

TAC concentrations should be maintained at < 15 ng/ml and age should be considered in patients undergoing BMT to avoid TI-LV dysfunction.

Liver disease and heart failure: Back and forth

In their clinical practice, physicians can face heart diseases (chronic or acute heart failure) affecting the liver and liver diseases affecting the heart. Systemic diseases can also affect both heart and liver. Therefore, it is crucial in clinical practice to identify complex interactions between heart and liver, in order to provide the best treatment for both. In this review, we sought to summarize principal evidence explaining the mechanisms and supporting the existence of this complicate cross-talk between heart and liver. Hepatic involvement after heart failure, its pathophysiology, clinical presentation (congestive and ischemic hepatopathy), laboratory and echocardiographic prognostic markers are discussed; likewise, hepatic diseases influencing cardiac function (cirrhotic cardiomyopathy). Several clinical conditions (congenital, metabolic and infectious causes) possibly affecting simultaneously liver and heart have been also discussed. Cardiovascular drug therapy may present important side effects on the liver and hepato-biliary drug therapy on heart and vessels; post-transplantation immunosuppressive drugs may show reciprocal cardio-hepatotoxicity. A heart-liver axis is drafted by inflammatory reactants from the heart and the liver, and liver acts a source of energy substrates for the heart.

Magnetic resonance imaging of the transplanted pediatric heart as a potential predictor of rejection

AIM

To evaluate cardiac magnetic resonance imaging (CMR) as a non-invasive tool to detect acute cellular rejection (ACR) in children after heart transplant (HT).

METHODS

Thirty pediatric HT recipients underwent CMR at the time of surveillance endomyocardial biopsy (EMB) and results were compared to 14 non-transplant controls. Biventricular volumes, ejection fractions (EFs), T2-weighted signal intensities, native T1 times, extracellular volumes (ECVs) and presence of late gadolinium enhancement (LGE) were compared between patients and controls and between patients with International Society of Heart and Lung Transplantation (ISHLT) grade ≥ 2R rejection and those with grade 0/1R. Heart rate (HR) and brain natriuretic peptide (BNP) were assessed as potential biomarkers.

RESULTS

Significant ACR (ISHLT grade ≥ 2R) was an infrequent event in our population (5/30, 17%). Ventricular volumes, EFs, LGE prevalence, ECVs, native T1 times, T2 signal intensity ratios, HR and BNP were not associated with the presence of ≥ 2R ACR.

CONCLUSION

In this pilot study CMR did not reliably identify ACR-related changes in pediatric HT patients.

Tacrolimus-Induced Cardiomyopathy in an Adult Renal Transplant Recipient

Tacrolimus-induced cardiomyopathy (TICM) is a rare but serious adverse effect of tacrolimus, which has been described primarily in pediatric non-renal transplant recipients. We describe a case of TICM in an adult renal transplant recipient that resulted in allograft dysfunction and multiple hospital admissions for heart failure exacerbation. Prompt and complete reversal of TICM occurred after tacrolimus discontinuation. Although tacrolimus-induced cardiomyopathy is reversible, availability of alternative immunosuppressants is limited, particularly in the setting of renal dysfunction. Available studies and patient-specific factors must be considered when determining an alternative maintenance immunosuppression regimen. We chose to use belatacept as alternative immunosuppression in this patient with TICM. Over the next 3 years, the patient remained free of hospital admissions and acute rejection, and demonstrated superior renal allograft function than was observed before her first heart failure admission. We believe that belatacept is an acceptable alternative to tacrolimus therapy for resolution of TICM.

Pharmacokinetics for once-daily modified release formulation of tacrolimus hydrate in unrelated hematopoietic stem cell transplantation

A once-daily modified release formulation of oral tacrolimus (Tac QD) has been developed in response to the problem of nonadherence. However, there have been no data available about the efficacy of Tac QD conversion from intravenous Tac (Tac i.v.) in allogeneic hematopoietic stem cell transplantation (allo-SCT). We analyzed the pharmacokinetics (PK) of Tac QD in allo-SCT recipients. A total of 10 patients with hematological malignancies who received allo-SCT from unrelated donors were enrolled. Patients received Tac i.v. at 0.03 mg/kg a day before transplantation. Administration of Tac i.v. was converted to Tac QD at a 1:4 ratio when the patients had recovered from regimen-related gastrointestinal toxicity and could tolerate oral medication. After conversion, six out of 10 patients (60 %) showed a sustained decrease in Tac exposure and required dose adjustment. The conversion from Tac i.v. to Tac QD should be performed under close medical supervision. Area under the curve (AUC) and the trough of Tac QD showed a correlation, and the trough should be maintained above 7.5 ng/ml to provide an adequate AUC. Although four patients received bone marrow from an HLA DRB1 1 antigen-mismatched unrelated donor, no patients developed grade III-IV acute graft-versus-host disease (GVHD). The modification of Tac QD to maintain a whole-blood trough concentration above 7.5 ng/ml may be as effective as Tac BID.

Cardiovascular effects of chronic treatment with a β2-adrenoceptor agonist relieving neuropathic pain in mice

Neuropathic pain is often a chronic condition, disabling and difficult to treat. Using a murine model of neuropathic pain induced by placing a polyethylene cuff around the main branch of the sciatic nerve, we have shown that chronic treatment with β-AR agonists is effective against neuropathic allodynia. β-mimetics are widely used against asthma and chronic obstructive pulmonary disease and may offer an interesting option for neuropathic pain management. The most prominent adverse effects of chronic treatment with β-mimetics are cardiovascular. In this study, we compared the action of low doses of the selective β(2)-AR agonist terbutaline and of a high dose of the mixed β(1)/β(2)-AR agonist isoproterenol on cardiovascular parameters in a neuropathic pain context. Isoproterenol was used as a positive control for some heart-related changes. Cardiac functions were studied by echocardiography, hemodynamic measurements, histological analysis of fibrosis and cardiac hypertrophy, and by quantitative real time PCR analysis of atrial natriuretic peptide (Nppa), periostin (Postn), connective tissue growth factor (Ctgf) and β-myosin heavy chain (Myh7). Our data show that a chronic treatment with the β(2)-AR agonist terbutaline at low antiallodynic dose does not affect cardiovascular parameters, whereas the mixed β(1)/β(2)-AR agonist isoproterenol induces cardiac hypertrophy. These data suggest that low doses of β(2)-AR agonists may provide a suitable treatment with rare side effects in neuropathic pain management. This study conducted in an animal model requires clinical confirmation in humans.