Comprehensive bio-imaging using myocardial perfusion reserve index during cardiac magnetic resonance imaging and high-sensitive troponin T for the prediction of outcomes in heart transplant recipients.

We sought to determine the ability of quantitative myocardial perfusion reserve index (MPRI) by cardiac magnetic resonance (CMR) and high-sensitive troponin T (hsTnT) for the prediction of cardiac allograft vasculopathy (CAV) and cardiac outcomes in heart transplant (HT) recipients. In 108 consecutive HT recipients (organ age 4.1±4.7 years, 25 [23%] with diabetes mellitus) who underwent cardiac catheterization, CAV grade by International Society for Heart & Lung Transplantation (ISHLT) criteria, MPRI, late gadolinium enhancement (LGE) and hsTnT values were obtained. Outcome data including cardiac death and urgent revascularization ("hard cardiac events") and revascularization procedures were prospectively collected. During a follow-up duration of 4.2±1.4 years, seven patients experienced hard cardiac events and 11 patients underwent elective revascularization procedures. By multivariable analysis, hsTnT and MPRI both independently predicted cardiac events, surpassing the value of LGE and CAV by ISHLT criteria. Furthermore, hsTnT and MPRI provided complementary value. Thus, patients with high hsTnT and low MPRI showed the highest rates of cardiac events (annual event rate=14.5%), while those with low hsTnT and high MPRI exhibited excellent outcomes (annual event rate=0%). In conclusion, comprehensive "bio-imaging" using hsTnT, as a marker of myocardial microinjury, and CMR, as a marker of microvascular integrity and myocardial damage by LGE, may aid personalized risk-stratification in HT recipients.

Long-term outcome after heart transplantation predicted by quantitative myocardial blush grade in coronary angiography.

The purpose of our study was to investigate whether the quantification of myocardial blush grade (MBG) during surveillance coronary angiography can predict long-term outcome after heart transplantation (HT). In 105 HT recipients who underwent cardiac catheterization, cardiac allograft vasculopathy (CAV) was assessed visually using the ISHLT grading scale (prospective cohort study). MBG was quantified by dividing the plateau of contrast agent gray-level intensity (G(max)) by the time-to-peak intensity (T(max)). In a subgroup (n = 72), myocardial perfusion index by cardiac magnetic resonance imaging (CMR) was assessed. During a mean follow-up duration of 2.7 (standard deviation [SD] 1.0) years, 26 patients experienced cardiac events, including 7 with cardiac death and 19 who underwent coronary revascularization. G(max)/T(max) was related to CAV by ISHLT criteria and to subsequent cardiac events. By univariate analysis, patient age, organ age, CAV, MBG and myocardial perfusion index by CMR were all predictive for cardiac events. Multivariable analysis demonstrated that G(max)/T(max) provided the most robust prediction of cardiac death (hazard ratio [HR] = 0.2, 95% confidence interval [CI] = 0.06-0.64, p < 0.01) and cardiac events (HR = 0.52, 95% CI = 0.32-0.84, p < 0.01), beyond clinical parameters and the presence of CAV. G(max)/T(max) is a valuable surrogate parameter of microvascular integrity, which is associated with cardiac death and revascularization procedures after HT.

Constrictive Pericarditis in the Presence of Remaining Remnants of a Left Ventricular Assist Device in a Heart Transplanted Patient.

Constrictive pericarditis (CP) is a severe subform of pericarditis with various causes and clinical findings. Here, we present the unique case of CP in the presence of remaining remnants of a left ventricular assist device (LVAD) in a heart transplanted patient. A 63-year-old man presented at the Heidelberg Heart Center outpatient clinic with progressive dyspnea, fatigue, and loss of physical capacity. Heart transplantation (HTX) was performed at another heart center four years ago and postoperative clinical course was unremarkable so far. Pharmacological cardiac magnetic resonance imaging (MRI) stress test was performed to exclude coronary ischemia. The test was negative but, accidentally, a foreign body located in the epicardial adipose tissue was found. The foreign body was identified as the inflow pump connection of an LVAD which was left behind after HTX. Echocardiography and cardiac catheterization confirmed the diagnosis of CP. Surgical removal was performed and the epicardial tubular structure with a diameter of 30 mm was carefully removed accompanied by pericardiectomy. No postoperative complications occurred and the patient recovered uneventfully with a rapid improvement of symptoms. On follow-up 3 and 6 months later, the patient reported about a stable clinical course with improved physical capacity and absence of dyspnea.

Increased incidence of acute graft rejection on calcineurin inhibitor-free immunosuppression after heart transplantation.

BACKGROUND: Calcineurin inhibitor (CNI)-free immunosuppression is used increasingly after heart transplantation to avoid CNI toxicity, but in the absence of a randomized trial, concerns remain over an increased rejection risk. METHODS: We studied the incidence of graft rejection episodes among all cardiac graft recipients, beginning with the first introduction of CNI-free protocols. We compared events during CNI-free and CNI-containing immunosuppression among 231 transplant recipients of overall mean age 55.2 ± 11.8 years, from a mean 5.2 ± 5.4 years after transplantation through a mean follow-up of 3.1 ± 1.4 years. We considered as acute rejection episodes requiring treatment those of International Society for Heart and Lung Transplantation. RESULTS: During the total follow-up of 685 patient years (CNI-containing, 563; CNI-free, 122), we performed 1,374 biopsies which diagnosed 78 rejection episodes. More biopsies were performed in CNI-free patients: biopsies/patient-month of CNI-containing, 0.13 versus CNI-free, 0.22 (P < .05). The incidence of rejection episodes per patient-month was significantly higher on CNI-free compared with CNI therapy, among patients switched both early and later after heart transplantation, namely, within 1 year, 0.119 versus 0.035 (P = .02); beyond 1 year, 0.011 versus 0.004 (P = .007); beyond 2 years, 0.007 versus 0.003 (P = .04); and beyond 5 years: 0.00578 versus 0.00173 (P = .04). CONCLUSIONS: Rejection incidence during CNI-free immunosuppression protocols after heart transplantation was significantly increased in both early and later postoperative periods. Given the potentially long delay to rejection occurrence, patients should be monitored closely for several months after a switch to CNI-free immunosuppressive protocols.

Proton pump inhibitor co-medication reduces active drug exposure in heart transplant recipients receiving mycophenolate mofetil.

BACKGROUND: Proton pump inhibitors (PPIs) are often prescribed for gastrointestinal discomfort after heart transplantation. This study investigated the impact of PPI use on mycophenolic acid (MPA) pharmacokinetics in heart transplant recipients receiving mycophenolate mofetil (MMF) in combination with a calcineurin inhibitor (tacrolimus [TAC]/cyclosporine [CsA]) or mammalian target of rapamycin inhibitor (sirolimus/everolimus). METHODS: Abbreviated MPA areas under the curve (AUCs; 0, 30, and 120 minutes after morning intake) were obtained in 19 patients on a PPI (initial examination) and 1 month after PPI discontinuation (follow-up). Mean patient age was 58.2 ± 8.8 years, and mean time after transplantation was 2.3 ± 4.0 years (range, 0.2-13.0 years). RESULTS: At initial examination mean daily MMF dose was 2.2 ± 0.8 g. MMF dose was kept unchanged for the duration of study (P = ns). Mean predose (C0) MPA serum concentrations were insignificantly lower with PPI comedication (2.5 ± 2.2 mg/L vs 2.8 ± 1.7 mg/L; P = .15). Dose-adjusted abbreviated MPA AUCs (adjusted to morning dose) were significantly lower during PPI therapy (45.2 ± 20.3 vs 65.2 ± 38.8 mg·h/L·g [MMF]; P = .02). CONCLUSIONS: Patients with PPI comedication during MMF therapy show significantly lower exposure to mycophenolic acid determined by dose-adjusted abbreviated MPA AUCs. Although the clinical relevance of this pharmacokinetic interaction was not determined in this study, MPA drug monitoring by limited sampling strategies might be helpful during changes in antacid comedication in patients on MMF.

Malignancies after heart transplantation: incidence, risk factors, and effects of calcineurin inhibitor withdrawal.

The objectives of the present study were to evaluate the incidence of malignancies and to describe the effects of immunosuppression on survival and recurrence of malignancies after heart transplantation (HTX). Data were analyzed in 211 cardiac allograft recipients, in whom HTX was performed between 1989 and 2005. All of these patients survived for more than 2 years after HTX and received induction therapy with antithymocyte globulin (RATG) guided by T-cell monitoring since 1994. An immunosuppressive regimen consisting of cyclosporine A (CsA) combined with azathioprine was followed by CsA and mycophenolate mofetil (MMF) in 2001; mammalian target of rapamycin (mTOR) inhibitors (everolimus/sirolimus) were used since 2003. Mean patient age at HTX was 51.4 ± 10.5 years; mean follow-up time after HTX 9.2 ± 4.7 years. Overall incidence of neoplasias was 30.8%. Individual risk factors associated with a higher risk of malignancy after HTX were higher age at transplantation (P = .003), male gender (P = .005) and ischemic cardiomyopathy before HTX (P = .04). Administration of azathioprine (P < .0001) or a calcineurin inhibitor (CNI) (P = .02) for more than 1 year was associated with development of malignancy, whereas significantly fewer malignancies were noticed in patients receiving an mTOR-inhibitor (P < .0001). Kaplan-Meier analysis demonstrated a strong statistical trend toward an improved survival in patients with a noncutaneous neoplasia switched to a CNI-free protocol (P = .05). This study demonstrated the impact of a variety of individual risk factors and immunosuppressive drugs on development of malignancy after HTX. Markedly fewer patients with noncutaneous malignancies died after switch to a CNI-free regimen, not quite reaching statistical significance by Kaplan-Meier analysis, however.

Increased adherence after switch from twice daily calcineurin inhibitor based treatment to once daily modified released tacrolimus in heart transplantation: a pre-experimental study.

BACKGROUND: Modified release tacrolimus (TAC) is a new, once-daily oral formulation of the established immunosuppressive agent TAC. Simplification of regimen has been associated with better adherence. This study evaluated patient adherence, as well as safety and efficacy among chronic stable heart transplantation (HT) patients switched from a conventional twice daily calcineurin inhibitor-based regimen (TAC or cyclosporine A [CsA]) to (once daily) modified release TAC. METHODS: We switched 54 chronic stable patients (41 males and 13 females) from twice daily dosing with conventional TAC or CsA to once daily dosing with modified release TAC. Self-reported adherence was assessed at baseline and at 4 months after the switch using the Basel Assessment of Adherence with Immunosuppressive Medication Scale [BAASIS]), a 4-item validated questionnaire including also a Visual Analogue Scale (VAS). Nonadherence was defined as any self-reported nonadherence on any item. RESULTS: Modified release TAC was discontinued in 4 patients because of diarrhea (n = 1) or gastrointestinal discomfort (n = 3) leaving 50 evaluable patients. Overall nonadherence at baseline for any of the 4 items was 74% versus 38% after 4 months (P = .0001). Thereafter, adherence improved in 28 patients (56.0%), was unchanged in 18 (36.0%), and decreased in 4 subjects (8.0%). The VAS score improved from 82.3% ± 2.6% to 97.5% ± 4.8% (P < .0001). No significant changes were observed after 4 months regarding hematologic, renal, or liver function parameters (all P = NS). CONCLUSIONS: Therapeutic regimens for transplant recipients are often complex, contributing to a high incidence of medication nonadherence. This study in chronic, stable, heart transplantation patients demonstrated a significant improvement in patient adherence after a switch to modified release TAC, which was generally well tolerated.

Cyclosporine withdrawal improves renal function in heart transplant patients on reduced-dose cyclosporine therapy.

Renal failure is a major cause of morbidity after heart transplantation. It is unclear whether calcineurin inhibitor (CNI) free immunosuppression provides more nephroprotection than low-dose CNI therapy. Thirty-nine patients with renal failure on low-dose cyclosporine A (CsA) were studied (62.9 +/- 8.7 years, five female, 8.2 +/- 4.3 years posttransplant, serum creatinine: 1.9 +/- 0.3 mg/dL, calculated GFR (cGFR): 48.2 +/- 18.3 mL/min, CsA C0 level: 64.0 +/- 19.9 ng/mL). All patients had been treated with low-dose CsA >6 months, renal function was stable or slowly decreasing (creatinine 1.7-3.5 mg/dL). Nineteen patients were randomized to discontinuation of CsA and overlapping rapamycin therapy initiation (RAPA), 20 patients continued low-dose CsA (control). Three patients (16%) discontinued rapamycin medication for side effects (diarrhea, skin rash), two patients developed pneumonia and pulmonary embolism, respectively, no rejection or other infectious complications were seen. After 6 months, renal function in the control group was unchanged. In the RAPA group, renal function markedly improved (creatinine: 2.08 +/- 0.15 to 1.67 +/- 0.13 mg/dL, cGFR: 48.5 +/- 21.4 to 61.7 +/- 21.4 mL/min (p < 0.001 within and between groups)). In carefully selected late survivors following heart transplantation who are at low risk of rejection, CNI-free rapamycin-based immunosuppression improves cGFR even in those already receiving low-dose CsA therapy. The results of this study warrant further confirmation in larger clinical trials that are powered to assess clinical outcomes.