Ultrastructure of pheochromocytoma: undescribed morphologic features.

We examined samples of human pheochromocytoma from 11 patients aged 30-70 years including one case of malignant pheochromocytoma with a view to identifying previously unreported ultrastructural details.We identified two types of nuclear inclusions consisting of irregularly shaped singular or multiple granulofibrillar formations with a typical concentric halo, on the one hand, and accumulations of egg-shaped structures consisting of granules and microfilaments, on the other. In some of the tumor cells, membrane-covered inclusions containing parallel laminar elements arranged in a paracrystalline, periodic fashion, or mega-mitrochondriae characterized by increased electrodensity of their matrix, and fibrillary material in the spaces between the cristae were present. A frequent finding consisted of typical ciliary formations, while rough/smooth tubular aggregates of different size occurred less frequently. Finally, we were able to demonstrate the uptake of norepinephrine by smooth muscle fibers in the periphery of arterial vessels as evidenced by linear accumulations of membrane-covered granules separating bands of contractile smooth muscle components in the peripheral layers of arterial vessels close to norepinephrine producing neoplastic cells.These findings represent ultrastructural features that contribute to further elucidating the ultrastructural characteristics of the human pheochromocytoma.

Comparison of the performance of the CRUSADE, ACUITY-HORIZONS, and ACTION bleeding risk scores in STEMI undergoing primary PCI: insights from a cohort of 1391 patients.

AIMS: To compare the performance of the CRUSADE, ACUITY-HORIZONS, and ACTION risk models in the ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). METHODS: We studied all consecutive patients with STEMI who underwent PPCI at our institution between 2006 and 2010 (n=1391). The CRUSADE, ACUITY-HORIZONS, and ACTION risk scores were calculated based on the patients' clinical characteristics. The occurrence of in-hospital major bleeding (defined as the composite of intracranial or intraocular bleeding, access site haemorrhage requiring intervention, reduction in haemoglobin ≥4 g/dl without or ≥3g/dl with overt bleeding source, reoperation for bleeding, or blood transfusion) reached 9.8%. Calibration and discrimination of the three risk models were evaluated by the Hosmer-Lemeshow test and the C-statistic, respectively. We compared the predictive accuracy of the risk scores by the DeLong non-parametric test. RESULTS: Calibration of the three risk scores was adequate, given the non-significant results of Hosmer-Lemeshow test for the three risk models. Discrimination of CRUSADE, ACUITY-HORIZONS, and ACTION models was good (C-statistic 0.77, 0.70, and 0.78, respectively). The CRUSADE and ACTION risk scores had a greater predictive accuracy than the ACUITY-HORIZONS risk model (z=3.89, p-value=0.0001 and z=3.51, p-value=0.0004, respectively). There was no significant difference between the CRUSADE and ACTION models (z=0.63, p=0.531). CONCLUSIONS: The CRUSADE, ACUITY-HORIZONS, and ACTION scores are useful tools for the risk stratification of bleeding in STEMI treated by PPCI. Our findings favour the CRUSADE and ACTION risk models over the ACUITY-HORIZONS risk score.

Platelet factor 4-positive thrombi adhering to the ventricles of a ventricular assist device in patients with heparin-induced thrombocytopenia type II.

BACKGROUND: Thromboembolism is a major complication in patients with ventricular assist devices (VADs). Drug anticoagulation and the use of biocompatible surfaces, such as coating with heparin, aim to reduce thromboembolism in these patients. Administration of heparin can lead to heparin-induced thrombocytopenia (HIT) type II, mainly through heparin/platelet factor 4 (PF4) antibodies. We assessed the presence of PF4 antibodies in VAD thrombi of patients with heparin-coated VADs and HIT II. METHODS: Thrombi (n = 6) were obtained from the replaced Excor ventricles of patients with HIT II after biventricular VAD implantation (Excor Adult; Berlin Heart, Germany). Excor ventricles were changed after clinical examination and suspicion of thrombi in the polyurethane valves. Expression of PF4- antibodies was assessed with the use of a polyclonal rabbit antibody (anti-PF4 antibody; Abcam, USA). Expression was assessed by 2 independent observers. RESULTS: Biopsies of all thrombi showed an extreme positive immunoreaction for PF4. No differences between the different thrombi and localization (left/right Excor ventricle) were observed. The thrombi were organized, without lamination of fibrin and cellular layers. CONCLUSIONS: Platelet surface expression of PF4 in the thrombi reflects HIT antigen presentation. The physical relationship between the PF4-positive thrombi and the heparin-coated surface suggests that onset of HIT II could be influenced by the immobilized heparin coating.

Indoleamine, 2-3 dioxygenase activity could be an early marker of graft rejection in heart transplantation.

BACKGROUND: The indoleamine, 2-3 dioxygenase (IDO) is an inducible intracellular enzyme with immunosuppressive effects mainly on lymphocyte populations. It has been postulated that indirect determination of IDO serum activity may be a marker of renal graft rejection, but its potential usefulness in heart transplantation (HT) is unknown. METHODS: This longitudinal study included 98 HT patients (83% males) who survived ≥1 year. Mean age was 54.14 ± 11.57 years. Serum IDO activity was analyzed one month after HT by means of high performance liquid chromatography and correlated with the cumulative incidence of acute rejection (AR) during one-year follow-up. AR was defined as biopsy-proven ≥ ISHLT grade 2R rejection or empirically treated non-biopsy-proven rejection. The study sample was divided into two groups: AR group (n = 51), including patients who experienced at least one AR episode during the first year after HT; No-AR group (N = 47), including the remaining patients. RESULTS: Mean serum IDO activity one month after HT was significantly higher (P = .021) in the AR group (3.32 ± 1.56) than in the no-AR group (2.62 ± 1.35). No significant association between serum IDO activity and gender (male: 3.1 ± 1.56, women: 2.43 ± 0.99, P = .092), recipient age (r = -.07, P = .943) or donor age (r = 0.108, P = 0.293) was observed. By means of binary logistic regression, an odds ratio of 1.4 [CI 95%: 1.033-1.876, P = .03] per unit increase of act-IDO was estimated, with no significant modification upon forced adjustment for age and sex. Mean glomerular filtration rate 1 month after HT was 67.01 ± 28.51 mL/min/m(2). No significant correlation between this parameter and serum IDO activity was observed (r = .160, P = .117). CONCLUSIONS: Our study suggests that serum IDO activity one month after HT might be associated with a higher risk of AR during one-year follow-up. This association seems to be independent of recipient gender, age or renal function.

Percutaneous coronary interventions and bypass surgery in patients with cardiac allograft vasculopathy: a single-center experience.

INTRODUCTION: Cardiac allograft vasculopathy (CAV) remains a major impediment to long-term survival after heart transplantation (HT). Limited data exist regarding the impact of coronary revascularization in these patients. OBJECTIVE: To evaluate the outcomes of revascularization procedures in patients with CAV compared with patients who did not undergo revascularization. METHODS: Retrospective analysis of 249 patients who underwent HT at our center between June 1998 and December 2009 and who were examined by coronary angiography after HT. We included patients with moderate or severe CAV according to the International Society for Heart and Lung Transplantation (ISHLT) nomenclature to evaluated outcomes after revascularization or diagnostic angiography. Major adverse cardiovascular events (MACE) comprised death, acute coronary syndrome, coronary revascularization, admission because of heart failure not due to an acute rejection episode, and cardiac retransplantation. RESULTS: Moderate or severe CAV was detected in 43 patients. Twelve (27.9%) underwent coronary revascularization: eight percutaneous interventions and four bypass surgeries. Indications for revascularization were symptomatic ischemia or noninvasive evidence of ischemia (n = 6, 14.0%) or high-risk asymptomatic CAV (n = 6; 14.0%), namely, lesions located in the left main or proximal anterior descending arteries or multivessel disease with left ventricular dysfunction. The remaining 31 (72.1%), who did not undergo revascularization showed an absence of ischemia during exercise echocardiography (n = 11; 25.6%) or diffuse disease not amenable to revascularization (n = 20; 46.5%). During a mean follow-up of 3.0 ± 2.4 years, MACE occurred in three revascularized patients (25.0%), in one with absence of stress-induced ischemia (9.1%) and in 13 with nonrevascularizable disease (65%; P = .012). CONCLUSIONS: Revascularization procedures were effective in HT patients with evidence of ischemia or high-risk CAV. Patients with absence of stress-induced ischemia have a good prognosis without revascularization. On the other hand, diffuse nonrevascularizable CAV is associated with a poor prognosis.

Cumulative incidence of cytomegalovirus infection and disease after heart transplantation in the last decade: effect of preemptive therapy.

INTRODUCTION: Infection by cytomegalovirus (CMV) is a major concern in solid organ transplant (SOT). It increases morbidity and mortality. The prevalence of CMV asymptomatic infection and disease is variable among centers, partially related to immunosuppressive protocols and therapeutic strategies to treat CMV. Induction therapy with basiliximab is associated with fewer CMV infections than therapy with OKT3. In our center, universal prophylaxis is used in the first month post-heart transplant (HT) and preemptive therapy (PET) is used later, according to viral load monitoring. OBJECTIVE: To analyze the short- and long-term incidence of CMV infection and disease post-HT according to CMV status of recipient (R)/donor (D) in a cohort of patients who received induction therapy with basiliximab. MATERIALS AND METHODS: Retrospective analysis of 201 consecutive patients over 18 years of age who underwent HT between February 2001 (when induction therapy with basiliximab was initiated) and June 2011. Patients were divided in two risk subgroups of developing CMV disease: high-risk (D+/R- or D-/R- who received blood transfusions or R-, or donor with unknown serostatus) and low-risk (any other combination). RESULTS: Of 201 patients (mean age 53.81 ± 11.61 years, 81.1% men). 165 patients were classified in the low-risk and 36 in the high-risk group. The cumulative incidence of asymptomatic CMV infection during the first year post-HT was 47%: 46% in the low-risk and 50% in the high-risk group (P = .668). The incidence of CMV disease during the first year post-HT was 7.5%: 3.6% in the low-risk versus 25% in the high-risk group (P < .001). CONCLUSIONS: In our series, asymptomatic CMV infection after HT is frequent, affecting almost 50% of patients. However, the incidence of CMV disease is very low (7.5%), which confirms the effectiveness of PET. The higher incidence of disease in the high-risk group recommends closer monitoring of viral load in these patients or performing more prolonged universal prophylaxis.

Clinical scores and patient risk stratification in non-ST elevation acute coronary syndrome.

BACKGROUND: Risk stratification of patients with unstable angina or non-ST-segment elevation myocardial infarction (UA/NSTEMI) is problematic given the heterogeneous presentation of the condition. This study was undertaken to compare, in UA/NSTEMI patients, the prognostic value of two clinical risk scores (RS) (i.e. Thrombolysis in Myocardial Infarction (TIMI) and physician's risk assessment (PRA)) and to assess whether serum biomarkers can increase the prognostic accuracy of these RS. METHODS: We prospectively assessed 610 consecutive UA/NSTEMI patients, 217 (36%) UA and 393 (64%) NSTEMI. In all patients RS, high sensitivity C-reactive protein, CD40 ligand, IL6, IL10, IL18, E-selectin, P-selectin, white blood cell count, neopterin, myeloperoxidase, fibrinogen and NT proBNP were assessed at study entry. The primary study endpoint was death and non-fatal MI at 30 and 360 days of follow-up. RESULTS: At 1 year, 54 patients (8.9%) had reached the primary study endpoint (26 suffered a cardiac death (4.3%) and 34 (5.6%) a non-fatal MI). For both RS, the study endpoint occurred more commonly in patients at a "higher risk" compared to those classified as being at a "lower risk". Moreover, TIMI and PRA RS had similar discriminatory accuracy. TIMI RS, however, was a better predictor of events than PRA at both 30- and 360-day follow-up. The inflammatory biomarkers assessed in the study did not improve significantly the predictive value of RS. CONCLUSIONS: Our study suggests both that TIMI RS is a better marker of risk than PRA RS and inflammatory biomarkers do not increase the predictive value of these clinical risk scores.

Prevalence of donor-transmitted coronary artery disease and its influence on heart transplant outcomes.

BACKGROUND: It is uncertain whether donor-transmitted coronary artery disease (DTCAD) affects heart transplant (HT) recipients. METHODS: This retrospective analysis includes records of all patients who underwent a HT at our center over an 8-year period, who survived for at least 1 month, and who were examined by coronary angiography within 2 months post-HT. We distinguished angiographically from keep ultrasonography (IVUS) detected DTCAD. Major adverse cardiovascular events (MACE) comprised death, myocardial infarction, unstable angina, coronary revascularization, and admission because of heart failure not due to an acute rejection episode. RESULTS: Among the 171 patients of mean age 53±13 years and including 83% men, 65 (38%) were evaluated by IVUS. Donors were aged 40±14 years (range=14-73). Angiographic DTCAD affected seven patients (4.1%), and IVUS-detected DTCAD, 35 (53.8% of those examined by IVUS). DTCAD donors were older than non-DTCAD donors, by an average of 13 years (P=.001) for angiographic DTCAD and 18 years (P<.0001) for IVUS-detected DTCAD. Two patients underwent percutaneous revascularization upon detection of angiographic DTCAD. The angiographic- and IVUS-detected DTCAD groups did not differ significantly from the corresponding non-DTCAD groups as regards MACE incidence during 54±41 and 38±20 months follow-up, respectively. Cox regression analysis with adjustment for relevant confounders confirmed that IVUS-detected DTCAD was not a predictor of MACE (hazard ratio 1.2, 95% confidence interval 0.2-8.1). CONCLUSIONS: Among HT patients surviving≥1 month, angiographic- and IVUS-detected DTCAD showed prevalences of <10% and >50%, respectively. Neither detection method was associated with a greater long-term incidence of MACE.

Conversion of heart transplant patients from standard to sustained-release tacrolimus requires a dosage increase.

INTRODUCTION: It has been suggested that for adequate maintenance of tacrolimus levels, the total daily dosage should be increased when switching from the conventional twice-daily regimen tacrolimus (CT) to once-daily sustained-release tacrolimus (SR-T). OBJECTIVE: To evaluate the safety and efficacy of a 25% increase in daily dosage when switching heart transplant (HT) patients from CT to SR-T. METHODS: We switched 75 HT patients including 72% males and an overall mean age of 55.6 years from CT to SR-T using a 25% increase in daily dosage. We screened for adverse events by measurements of lipids, creatinine, glycemia, and tacrolimus in blood samples taken at 1, 3, 7, and 12 weeks after the conversion, as well as by repeated echocardiography and routine clinical examinations. RESULTS: Just two patients (2.7%) were returned to CT because of failure of SR-T to attain therapeutic levels. In the remainder of subjects, tacrolimus levels remained stable, with trough values of 8.7±3.2, 8.7±2.9, 8.3±2.6, and 7.5±2.0 mg/dL, respectively. Twenty-three patients (31%) required no dosage change in the first 3 months, but 44 (33%) required one or two changes. No departure from therapeutic levels was associated with rejection; there was no case of severe intercurrent infection. We did not observe significant changes in glycemia, creatinine, lipid profile, or blood pressure. CONCLUSIONS: Administration of SR-T at a dosage 25% higher than the daily dosage of CT was safe. It ensured adequate tacrolimus levels in one-third of patients. Nevertheless, strict analytical surveillance is necessary during the initial months to allow dosage adjustments and to detect the minority of patients for whom SR-T does not achieve therapeutic tacrolimus levels.

Long-term outcome in heart transplant patients with pretransplant malignancies.

INTRODUCTION: Neoplasms have classically been considered a contraindication for heart transplantation (HT) because of the possibility of recurrence during immunosuppressive therapy. There are few cases of patients who suffered a pretransplant malignancy (PTM); however the appropriate interval free of a malignancy (IFoM) before heart transplantation is unclear. Our study sought to determine the long-term outcomes after transplantation among patients who had suffered a prior neoplasm compared with our overall cohort. METHODS: This retrospective, single-center study included 595 heart transplant recipients ungrafted between 1991 and 2009. We determined PTM location, histology, and IFoM. We examined donor and recipient factors and post-HT data of rejections, infections, neoplasms, and survival associated with a poor prognosis. RESULTS: Twelve patients with different types, locations, and histological grades of PTM represented 66.7% women versus 16.1% women in the overall series (P<.01). There were no differences in recipient age or clinical characteristics (diabetes mellitus, arterial hypertension, previous renal failure, or New York Heart Association class), number of emergency cases, or graft ischemia time. Mean IFoM was 114.3 months (range=5.3-350.4). After heart transplantation, there were no significant differences between the number of infections (47.9%; n=[279] vs 33.3% n=4; P=.39), rejection episodes (44.4% [259] vs 50% [6], P=0.77) or post-HT malignancies (12.2% [70] vs 0%, P=0.37) between the overall series and the patients with PTM. None of the patients with PTM suffered a recurrence of the neoplasm. Actuarial survivals at 1, 3, and 5 years were 82%, 76%, and 70% among patients without PTM and 75%, 75%, and 56% among those with PTM (P=.70). CONCLUSION: Patients with PTM and an appropriate IFoM with regard to tumor lineage showed similar rates of survival and complications as those of the overall series. This series suggested that appropriately selected patients with a cured PTM can be candidates for HT.