Antonio Gambino

Immune and Nonimmune Predictors of Cardiac Allograft Vasculopathy Onset and Severity: Multivariate Risk Factor Analysis and Role of Immunosuppression

We studied 361 patients, to evaluate risk factors for cardiac allograft vasculopathy (CAV) onset and severity/diffusion in heart transplantation (HT). Rejection scores (RS) on endomyocardial biopsy were calculated (first year and whole follow‐up). CAV onset was defined as any lesion seen at yearly angiography. A CAV severity/diffusion index was calculated for each patient summing up the scores of all lesions. Cox multivariate analysis included: donor age, sex, and weight; recipient sex, age, pre‐HT diagnosis, hypertension, diabetes and hyperlipidemia post‐HT; number of treated rejections and RS; and immunosuppressive dosage at 3, 6, and 12 months. CAV frequency was 2% at 1 year, 22% at 5 and 39% at 10 years. Risk factors for CAV onset were older donor age [p < 0.0001, relative risk (RR) = 9.9], male donor (p < 0.001, RR = 3.2), high RS for severe (≥ 3A) grades (p < 0.02, RR = 2.01), high cyclosporine at 3 months (p < 0.02, RR = 1.9). Risk factors for CAV severity/diffusion were higher donor weight (p < 0.01, RR = 7.5), high prednisone dosage at 1 year (p < 0.0001, RR = 21.1), and coronary disease pre‐HT (p < 0.002, RR = 9.7). High RS was an independent predictor for CAV onset, not severity/diffusion. This suggests an immune basis for CAV onset and nonimmune modulation for progression. High RS for severe grades may provide a predictor for patients at risk.

Coronary flow velocity pattern and coronary flow reserve by contrast-enhanced transthoracic echocardiography predict long-term outcome in heart transplantation.

Background— We assessed coronary flow velocity pattern and coronary flow reserve (CFR) by contrast-enhanced transthoracic echocardiography (CE-TTE) as markers of major adverse cardiac events (MACE) related to cardiac allograft vasculopathy (CAV) after heart transplantation (HT). Methods and Results— Deceleration time of diastolic flow velocity (DDT) and CFR were measured in the left anterior descending coronary artery (LAD) by CE-TTE in 66 consecutive HT patients (follow-up 19±5 months). CFR was calculated as the ratio of hyperemic to basal diastolic flow velocity. Angiographies were analyzed by a qualitative grading system; CAV was defined as changes grade II or higher. MACE were cardiac death, stent implantation, and heart failure. Patients with MACE had higher CAV incidence (P=0.004) and grade (P=0.008), shorter DDT (P=0.006), and lower CFR (P=0.008). A receiver-operating characteristic–derived DDT cutpoint ≤840 ms (area under the curve 0.793; P=0.01) was 75% specific and 86% sensitive for predicting MACE, with positive predictive value (PPV) and negative predictive value (NPV) of 33% and 97%, respectively (P=0.002). A CFR cutpoint of ≤2.6 (area under the curve 0.746; P=0.01) was 62% specific and 91% sensitive for predicting MACE (PPV =32%, NPV =97%) (P=0.001). Patients with CFR ≤2.6 and patients with DDT ≤840 ms had a lower survival free from MACE (P=0.006 and P=0.009, respectively). By Cox regression, only a lower CFR predicted the risk of MACE (relative risk 3.1; 95% CI, 1.26 to 7.9; P=0.01). Conclusions— In HT patients, shorter DDT and lower CFR by CE-TTE are reliable markers for CAV-related MACE. CFR is the main independent predictor of MACE.

Posttraumatic stress disorder and depression in heart transplantation recipients: the relationship with outcome and adherence to medical treatment

OBJECTIVE There is growing evidence of the importance of psychiatric risk factors for predicting the outcome of heart transplantation (HT) recipients. The aim of our study was to investigate the role of major depression and posttraumatic stress disorder (PTSD) in the prediction of the outcome of HT in a consecutive sample of 107 recipients. METHOD All subjects of the study underwent a structured diagnostic interview for assessing the presence of pretransplant and posttransplant major depression and transplantation-related PTSD 1 to 5 years after HT. The adherence to medical treatment was assessed some months after the structured interview. The medical outcome (acute rejections, cancer, mortality) was followed up for 8 years on average after the interview, using a prospective design. RESULTS Estimated frequency of psychiatric diagnoses after HT was 12% for transplantation-related PTSD and 41% for major depression. The presence of an episode of major depression prior to HT is a significant independent risk factor for posttransplant malignancies. Age, posttransplant malignancies and poor adherence are significant predictors of mortality in the survival analyses. CONCLUSIONS The present study highlights the importance of the assessment of psychosocial variables and psychiatric diagnoses before and after transplantation in HT recipients. Our findings have important clinical implications and require replication with larger samples.

Coronary flow reserve by contrast-enhanced echocardiography : A new noninvasive diagnostic tool for cardiac allograft vasculopathy

Noninvasive tests have proven unsatisfactory in cardiac allograft vasculopathy (CAV) diagnosis. We assessed coronary flow reserve (CFR) by contrast‐enhanced transthoracic echocardiography (CE‐TTE) in heart transplantation (HT). CFR was assessed in the left anterior descending coronary artery in 73 HT recipients (59 male, aged 50 ± 12 years at HT), at 8 ± 4.5 years post‐HT. CFR measurements were taken blindly from coronary angiographies. CFR cut points were the standard value of ≤2 and those defined by receiver operating characteristics (ROC) curve analysis. CFR was lower in patients with CAV (2.3 ± 0.7 vs. 3.2 ± 0.5, p < 0.0001). The ≤2 cut point was 100% specific and 38% sensitive. The ≤2.7 cut point, optimal by ROC analysis, was 87% specific and 82% sensitive. Accuracy rose from 71% with the standard ≤2 cut point to 85% with the optimal cut point of ≤2.7. CFR by CE‐TTE may offer promise as a novel, easily repeatable and accurate noninvasive tool in CAV detection. However, further longitudinal studies in larger patient cohorts are warranted before widespread adoption can be advocated.

Human cytomegalovirus-specific T-cell immune reconstitution in preemptively treated heart transplant recipients identifies subjects at critical risk for infection.

ABSTRACT Human cytomegalovirus (CMV) infection represents a major threat for heart transplant recipients (HTXs). CMV-specific T cells effectively control virus infection, and thus, assessment of antiviral immune recovery may have clinical utility in identifying HTXs at risk of infection. In this study, 10 CMV-seropositive (R+) pretransplant patients and 48 preemptively treated R+ HTXs were examined before and after 100 days posttransplant. Preemptive treatment is supposed to favor the immune recovery. CMV DNAemia and gamma interferon enzyme-linked immunosorbent spot (ELISPOT) assay were employed to assess the viremia and immune reconstitution. HTXs could be categorized into three groups characterized by high (>100), medium (50 to 100), and low (<50) spot levels. Early-identified high responders efficiently controlled the infection and also maintained high immunity levels after 100 days after transplant. No episodes of grade ≥2R rejection occurred in the high responders. Midresponders were identified as a group with heterogeneous trends of immune reconstitution. Low responders were 41% and 21% of HTXs before and after 100 days posttransplant, respectively. Low responders were associated with a higher incidence of infection. The effect of viremia on immune recovery was investigated: a statistically significant inverse correlation between magnitude of viremia and immune recovery emerged; in particular, each 10-fold increase in viremia (>4 log10 DNAemia/ml) was associated with a 36% decrease of the ELISPOT assay spot levels. All episodes of high viremia (>4 log10 DNAemia/ml) occurred from 1 to 60 days after transplant. Thus, the concomitant evaluation of viremia and CMV immune reconstitution has clinical utility in identifying HTXs at risk of infection and may represent a helpful guide in making therapeutic choices.

Can C4d immunostaining on endomyocardial biopsies be considered a prognostic biomarker in heart transplant recipients

Background. The aim of this study was to assess the significance of positive C4d capillary immunostaining of endomyocardial biopsies and its correlation to clinical outcome in adult heart transplant recipients. Methods. Nine hundred eighty-five endomyocardial biopsies from 107 heart transplant recipients were evaluated. Immunostaining for detection of intragraft C4d capillary deposition was performed on paraffin-embedded tissue using anti-human C4d polyclonal antibody. Results. Positive staining of C4d was present in 36 patients (34%) and antibody-mediated rejection in eight patients (7%). The patients were subdivided into four groups on the basis of their C4d, circulating antidonor antibodies (donor-specific antibodies [DSAs]), and graft function: group 1=C4d positive, DSA negative, and no graft dysfunction; group 2=C4d positive, DSA positive, and no graft dysfunction; group 3=C4d positive, DSA positive, and signs of graft dysfunction, and group 0 (control)=all negative. An higher mortality risk was found in C4d-positive patients, when compared with negative ones (unadjusted hazard ratios: group 1: 18, group 2: 61, and group 3: 32-fold risk; P<0.0001). Conclusions. Antibody-mediated rejection is a complex and ongoing phenomenon with different phenotypic features. C4d positive predicts worse prognosis. C4d negative and DSA can be used as early mortality predictors in patients without signs of graft dysfunction.

Coronary Flow Reserve by Transthoracic Echocardiography Predicts Epicardial Intimal Thickening in Cardiac Allograft Vasculopathy

Cardiac allograft vasculopathy (CAV) is the leading cause of morbidity and mortality in heart transplantation (HT). We sought to investigate the role of coronary flow reserve (CFR) by contrast‐enhanced transthoracic echocardiography (CE‐TTE) in CAV diagnosis. CAV was defined as maximal intimal thickness (MIT) assessed by intravascular ultrasound (IVUS) ≥0.5 mm. CFR was assessed in the left anterior descending coronary artery in 22 HT recipients at 6 ± 4 years post‐HT. CAV was diagnosed in 10 patients (group A), 12 had normal coronaries (group B). The mean MIT was 0.7 ± 0.1 mm (range 0.03–1.8). MIT was higher in group A (1.16 ± 0.3 mm vs. 0.34 ± 0.07 mm, p < 0.0001). CFR was 3.1 ± 0.8 in all patients and lower in group A (2.5 ± 0.6 vs. 3.7 ± 0.3, p < 0.0001). CFR was inversely related with MIT (r =−0.774, p < 0.0001). A cut point of ≤2.9, identified as optimal by receiver operating characteristics analysis was 100% specific and 80% sensitive (PPV = 100%, NPV = 89%, Accuracy = 91%). CFR assessment by CE‐TTE is a novel noninvasive diagnostic tool in the detection of CAV defined as MIT ≥0.5 mm. CFR by CE‐TTE may reduce the need for routine IVUS in HT.

Heart transplantation in patients with inherited myopathies associated with end-stage cardiomyopathy: Molecular and biochemical defects on cardiac and skeletal muscle

CARDIAC involvement in patients with inherited myopathies is well described in the literature. In dystrophinopathies (Duchenne muscular dystrophy [DMD], Becker muscular dystrophy [BMD], and DMD/ BMD carriers), dilated cardiomyopathy (DCM) has been reported in association with muscular dystrophy. In addition, in cases with particularly mild skeletal muscle involvement, cardiomyopathy may be the primary clinical feature and the main clinical problem. In mitochondrial myopathies, cardiac conduction defects have been described in many patients, whereas both hypertrophic (HCM) and DCM have been reported infrequently. In desminopathies, cardiomyopathy with conduction abnormalities is frequently associated with myopathy and may predominate. Up to now, end-stage cardiomyopathy resulting from dystrophinopathies, desminopathies, and mitochondrial myopathies have been accepted for heart transplantation (HTx) with reluctance because of a high perioperative risk caused by physical disability and restrictive respiratory failure. Moreover, a suspected rapid onset of cardiomyopathy of the transplanted heart is a further concern. Here we report five cases of end-stage cardiomyopathy with mild to moderate myopathies, who successfully underwent heart transplantation and were followed up for 72 months after surgery.

Role of morphologic parameters on endomyocardial biopsy to detect sub-clinical antibody-mediated rejection in heart transplantation.

BACKGROUND The present study evaluated if morphologic parameters detect signs of early sub-clinical or latent stages of antibody-mediated rejection (AMR) and their correlation with C4d staining in cardiac transplants recipients. METHODS The study reviewed 1,270 endomyocardial biopsies (EMB) from 131 patients. Of these, 61 stained positive for C4d in the absence of acute cellular rejection >2R. Sixty-six EMB specimens negative for C4d were matched for pre-transplant diagnosis, time after transplantation, age, and acute cellular rejection (ACR) grading. Histopathologic evaluation and C4d staining were performed on formalin-fixed, paraffin-embedded sections using the C4d polyclonal antibody. RESULTS Of the 8 histologic characteristics evaluated, only endothelial swelling (78.7% sensitivity, 28.8% specificity; positive likelihood ratio, 1.10) and interstitial edema (77% sensitivity, 31.8% specificity; positive likelihood ratio, 1.13) could be considered fair predictors of C4d capillary positivity. The presence of mononuclear cells in capillaries in relation to C4d positivity showed 39.3% sensitivity and 68.2% specificity. Combining the parameters endothelial swelling and mononuclear cells in capillaries, sensitivity was 31.1% (95% confidence interval [CI] 19.9-44.3) and specificity was 71.2% (95 CI, 58.8-81.7), with a positive likelihood ratio of 1.08 (95% CI, 0.68-1.84). CONCLUSIONS Our results showed that histologic parameters did not always detect signs of early sub-clinical or latent stages of AMR. Combining the parameters of endothelial swelling and intracapillary mononuclear cells did not significantly improve the sensitivity or specificity. Screening recommendations should, therefore, be modified to include more sensitive tests such as C4d staining in the routine protocol to improve patient risk stratification.

C2 is superior to C0 as predictor of renal toxicity and rejection risk profile in stable heart transplant recipients

To assess whether cyclosporine A (CsA) 2‐h peak (C2) is superior to trough levels (C0) for Neoral dose monitoring in heart transplantation (HT), we studied 928 C0–C2 paired determinations from 313 stable HT patients (257 male, aged 50 ± 14 years at HT, follow‐up 6.9 ± 4 years), on a C0‐based regimen. Our target C0 levels (ng/ml) were 150–400 (first 3 months), 150–300 (4–12 months), 100–250 (>12 months). Mean C0 and C2 levels were 268 ± 80 and 1031 ± 386, respectively (first 3 months); 230 ± 49 and 955 ± 239 (4–12 months); 157 ± 53 and 745 ± 236 (>12 months). For patients within the target C0, the corresponding C2 were 600–1500 (first 3 months), 600–1300 (4–12 months), 400–1100 (>12 months). C2 correlated with C0 (r = 0.64, P = 0.0001). C2 correlated better with CsA dose than C0 (r = 0.41, P = 0.0001 vs. r = 0.33, P = 0.0001). Between patients, CsA dose varied by a factor of 9.3; the C/dose ratio varied by a factor of 8.5 for C2 and of 15.6 for C0. Patients with higher C2 (>740) had higher severe rejection score at 2 years (P = 0.02) than patients with lower C2. This did not apply to C0. Both C2 and C0 correlated with blood urea (r = −0.18, P = 0.0001; r = −0.12, P = 0.0002) and creatinine (r = −0.19, P = 0.0004; r = −0.19, P = 0.0001 respectively). By logistic regression higher C2 (>740) was associated with higher total severe rejection score at 2 years (P = 0.006). C2 showed better correlation with CsA dose, renal function, rejection profile and less variability between patients than C0. C2 may improve CsA‐based immunosuppression in HT.