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The majority of patients with chronic heart failure (HF) receive long-term treatment with loop diuretics. The comparative effectiveness of different loop diuretics is unknown. We searched PubMed, clinicaltrials.gov , the Cochrane Central Register of Controlled Trials and the European Union Clinical Trials Register for randomised clinical trials exploring the efficacy of the loop diuretics azosemide, bumetanide, furosemide or torasemide in patients with HF. Comparators included placebo, standard medical care or any other active treatment. The primary endpoint was all-cause mortality. Secondary endpoints included cardiovascular mortality, HF-related hospitalisation and any combined endpoint thereof. Hypokalaemia and acute renal failure were defined as additional safety endpoints. Evidence was synthesised using network meta-analysis (NMA). Thirty-four trials reporting on 2647 patients were included. The overall quality of evidence was rated as moderate. NMA demonstrated no significant differences between loop diuretics with respect to all-cause mortality, cardiovascular mortality or hypokalaemia. In contrast, torasemide ranked best in terms of HF hospitalisation, and there was a trend towards benefits with torasemide with regard to occurrence of acute renal failure. Sensitivity analyses excluding trials with a follow-up < 6 months, trials with a cross-over design and those including < 25 patients confirmed the main results. We found no significant superiority of either loop diuretic with respect to mortality and safety endpoints. However, clinicians may prefer torasemide, as it was associated with fewer HF-related hospitalisations. [ABSTRACT FROM AUTHOR]

Keywords: amyloid; cardiovascular diseases; protein aggregates; proteostasis; proteostasis deficiencies; unfolded protein response A handful of chaperones can accompany proteins to the extracellular space where they can fortify protein folding, and proteases in the extracellular space contribute to the degradation of misfolded proteins (Figure L). Hearts of patients with dilated cardiomyopathy or ischemic heart disease also manifest aberrant protein aggregation and accumulation of ubiquitylated proteins, and activation of unfolded protein responses, as well. Amyloid, cardiovascular diseases, protein aggregates, proteostasis, proteostasis deficiencies, unfolded protein response. [Extracted from the article]

Background: Stroke can lead to cardiac dysfunction in patients, but the mechanisms underlying the interaction between the injured brain and the heart are poorly understood. The objective of the study is to investigate the effects of experimental murine stroke on cardiac function and molecular signalling in the heart. Methods and results: Mice were subjected to filament‐induced left middle cerebral artery occlusion for 30 or 60 min or sham surgery and underwent repetitive micro‐echocardiography. Left ventricular contractility was reduced early (24–72 h) but not late (2 months) after brain ischaemia. Cardiac dysfunction was accompanied by a release of high‐sensitive cardiac troponin (hsTNT (ng/ml): d1: 7.0 ± 1.0 vs. 25.0 ± 3.2*; d3: 7.3 ± 1.1 vs. 52.2 ± 16.7*; d14: 5.7 ± 0.8 vs. 5.2 ± 0.3; sham vs. 60 min. MCAO; mean ± SEM; *p < 0.05); reduced heart weight (heart weight/tibia length ratio: d1: 6.9 ± 0.2 vs. 6.4 ± 0.1*; d3: 6.7 ± 0.2 vs. 5.8 ± 0.1*; d14: 6.7 ± 0.2 vs. 6.4 ± 03; sham vs. 60 min. MCAO; mean ± SEM; *p < 0.05); resulting from cardiomyocyte atrophy (cardiomyocyte size: d1: 12.8% ± 0.002**; d3: 13.5% ± 0.002**; 14d: 6.3% ± 0.003*; 60 min. MCAO vs. sham; mean ± SEM; **p < 0.01; *p < 0.05), accompanied by increased atrogin‐1 and the E3 ubiquitin ligase murf‐1. Net norepinephrine but not synthesis was increased, suggesting a reduced norepinephrine release or an increase of norepinephrine re‐uptake, resulting in a functional denervation. Transcriptome analysis in cardiac tissue identified the transcription factor peroxisome proliferator‐activated receptor gamma as a potential mediator of stroke‐induced transcriptional dysregulation involved in cardiac atrophy. Conclusions: Stroke induces a complex molecular response in the heart muscle with immediate but transient cardiac atrophy and dysfunction. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 53-year-old Caucasian female diagnosed with elevated high sensitivity cardiac troponin T (cTn), regulatory protein of the striated muscle regulating excitation–contraction coupling in the heart, without previous history of cardiac disease. Topics discussed were pathobiological mechanisms leading to elevated troponin values, elevation of N-terminal pro B-type natriuretic peptide and creatinine kinase and blood analysis of patient.

Aims Autoimmune-associated proarrhythmia in dilated cardiomyopathy (DCM) is poorly understood. Given the significance of KCNQ1 potassium channels in heart rhythm disorders, we hypothesized that circulating anti-KCNQ1 autoantibodies directly modulate cardiac electrophysiology in DCM patients. The purpose of this pilot study was to characterize ion channel autoantibodies in DCM targeting the cardiac repolarizing K+ current, IKs, and the underlying KCNQ1 potassium channel. Methods and results One hundred and fifty DCM patients were screened for anti-KCNQ1 autoantibodies using an enzyme-linked immunosorbent assay. Autoantibodies targeting the extracellular pore domain of the KCNQ1 channel were detected in 6% of study patients. Seropositive individuals exhibited significantly shorter corrected QT intervals when compared with seronegative patients (371 ± 39.9 ms vs. 408 ± 47.9 ms; P = 0.036). There was no difference in clinical severity of heart failure between groups. The functional significance of anti-KCNQ1 antibodies was determined in human embryonic kidney 293 cells expressing KCNQ1/KCNE1 using the whole-cell patch clamp technique. IKs recordings demonstrated a 2.7-fold increase in mean current density on exposure to patients' sera containing anti-KCNQ1 antibodies in contrast to seronegative controls (8.74 ± 1.44 pA/pF vs. 3.26 ± 0.36 pA/pF; P = 0.003). IKs enhancement was not associated with increased KCNQ1 protein levels or altered cell surface expression of the channel. Conclusion Anti-KCNQ1 autoantibodies found in a subgroup of DCM patients are associated with QT interval shortening and increased IKs current. [ABSTRACT FROM AUTHOR]

Background: Elevated cardiac troponin (cTn) has been reported to occur with AVNRT. Little is known about prevalence, kinetic changes, and possible reasons of increased cTn. Methods: We evaluated 139 consecutive patients presenting with AVNRT to the emergency department between 2006 and 2010. Cardiac troponin T (cTnT) was measured serially at baseline, after three and six hours. Patients were evaluated for the presence of structural heart disease or CAD. Troponin was defined as elevated if a value exceeded the lower limit of detection (10 ng/l) using the fourth generation cTnT, or if the value > 99th percentile (14 ng/l) using the new highly sensitive cTn assay. Results: A cTnT > LLD ( n = 29) or > 99th percentile ( n = 16) was found in 45 patients (32.4%) within the initial six hours after hospitalization. All patients were symptomatic with palpitations, chest discomfort or dyspnea. A complete cardiac evaluation was carried out, including coronary angiography in 32 patients demonstrating an underlying structural heart disease or CAD in 18 cases (56%). Significant CAD was detected in 16 cases. 8 cases required PCI during hospitalization. Elevated cTnT was seen in patients with and without structural heart disease. Conclusions: AVNRT is a possible reason for elevated cTnT, even in the absence of relevant structural heart disease or CAD. [ABSTRACT FROM AUTHOR]

Aims N-terminal pro brain natriuretic peptide (NT-proBNP) is a potent marker of heart failure and other cardiac diseases. The value of NT-proBNP testing in the medical emergency department (ED) was assessed in patients >65 years old. Methods and results This large, prospective, randomized, controlled, multicentre trial was conducted in six medical EDs. Data for evaluation of the primary endpoint of hospitalization were available for 1086 patients. Median NT-proBNP was 582 pg/mL. A total of 16% of patients presented with NT-proBNP <150 pg/mL (low), 55% with NT-proBNP between 150 and 1800 pg/mL (intermediate), and 29% with NT-proBNP >1800 pg/mL (high). NT-proBNP was positively correlated with hospital admission [ odds ratio (OR) for high vs. low 2.9, P < 0.0001], length of stay (8.5 days vs. 3.5 days for high vs. low, P < 0.01), in-hospital death (3.9% vs. 0% for high vs. low, P < 0.01), 6 months re-hospitalization (OR for high vs. low 5.1, P < 0.0001), and 6 months death or re-hospitalization (OR for high vs. low 5.7, P < 0.0001). Knowledge of NT-proBNP had no significant effect on the primary endpoint hospital admission and the secondary endpoints intermediate/intensive care unit (IMC/ICU) admission, length of stay, re-hospitalization and death, or re-hospitalization in the total cohort. However, patients with high open NT-proBNP (>1800 pg/mL) were more likely to be admitted to the hospital (P < 0.05) and IMC/ICU (P < 0.05), whereas patients with low open NT-proBNP (<150 pg/mL) were less likely to be admitted (P < 0.05) compared with patients with blinded NT-proBNP. Conclusion Although NT-proBNP does not affect overall hospitalization, it is associated with better stratification of patient care and is strongly correlated with subsequent utilization of hospital resources and prognosis. [ABSTRACT FROM PUBLISHER]

The article offers information on a study which examined the comprehensive and cost-efficient genetic diagnosis of cardiomyopathies through the use of microarray-based target enrichment approach followed by SOLiD next-generation sequencing (NGS). The researchers developed an array-based subgenomic enrichment diagnostic approach to determine mutations in patients dilated cardiomayopathy (DCM) and hypertrophic cardiomyopathy (HCM). It notes that the approach resulted to high sequence coverage of cardiomyopathy genes.

The article discusses a study on the GΒ γ-sequestering peptide Β-adrenergic receptor (AR_ kinase (Beta ARK). It was demonstrated that ΒARKct enhances the cardiac L-type Ca2+ channel (LCC) current (ICa) both in normal (NC) and failing (FC) adult rats on ΒAR stimulation. The study concluded that betaARKc-mediated improvement of ICa rendered cardiomyocytes neither susceptible to ΒAR-induced damage nor arrhythmogenic sarcoplasmic reticulum Ca2+ leakage.

Background: Cardiac Troponin-T (cTnT) is a cardio-specific indicator of myocardial necrosis due to ischemic or non-ischemic events. Considering the multiple causes of myocardial injury and treatment consequences there is great clinical need to clarify the underlying reason for cTnT release. We sought to implement acute CMR as a noninvasive imaging method for differential diagnosis of elevated cTnT in chest-pain unit (CPU) patients with nonconclusive symptoms and ECG-changes and a low to intermediate probability for coronary artery disease (CAD). Results: CPU patients (n = 29) who had positive cTnT were scanned at 1.5T with a new step-by-step CMR algorithm including cine-, perfusion-, T2-, angiography-and late gadolinium enhancement (LGE) imaging. For comparison patients also underwent echocardiography and coronary angiography if necessary. CMR was conducted successfully in all patients and detected 93% of cTnT releases of unknown cause, without adverse hemodynamic or arrhythmic events. Acute myocardial infarction was detected in 11, pulmonary embolism in 6, myocarditis in 5, renal disease and cardiomyopathy in 2, storage disorder in 1 patient. In 2 patients CMR was unable to reveal the cause of cTnT elevations. Mean CMR scan-time was 35 ± 8 min. In 4 patients, CMR led to immediate coronary angiography with correct prediction of the infarct related artery. Conclusions: We implemented a novel CMR algorithm to show the clinical value and practical feasibility of acute CMR in a non-conclusive patient cohort with unclear cTnT elevation. Since this pilot study has shown the feasibility of CMR in CPU patients, further prospective studies are warranted to compare CMR with other imaging modalities. [ABSTRACT FROM AUTHOR]

Biovariability, reference change values (RCV), and index of individuality (IOI) have not been previously described for NT-proANP or GDF15. Also, the relation of changes of these markers to other clinical variables or biomarkers is unknown. In 41 patients with stable chronic systolic dysfunction, NT-proANP and GDF15 were measured alongside with clinical variables/markers comprising NT-proBNP, hsTnT, and hsCRP at four sampling intervals (2 weeks, 1-, 2-, 3-month intervals). At 2 weeks, 1-, 2-, and 3-month-follow-up, individual NT-proANP variations were 27.1, 22.5, 28.9, 15.6%, respectively, corresponding to RCVs of 53.2, 62.4, 80.2, and 43.2%, respectively. For GDF15, the respective individual variations were 6.8, 4.1, 5.5, 6.8%, corresponding to RCVs of 18.8, 11.5, 15.3 and 18.8%. Neither changes of NT-proANP or GDF15 correlated with changes in any of the clinical variables or biomarkers examined except for GDF15 with renal function. Baseline hormonal levels and clinical variables did not consistently influence the extent of change. The IOI was 0.19–0.35 according to interval for NT-proANP and 0.06–0.09 for GDF 15. In patients with CHF preselected for clinical stability changes of NT-proANP at intermediate follow-up do not correlate with changes in other variables; changes of GDF15 inversely correlate with renal function. The extent of change in both markers is not related to baseline hormonal levels or other baseline variables. RCVs are high for NT-proANP and low for GDF15, while inter-individual variation is high in GDF15 and intermediate in NT-proANP. [ABSTRACT FROM AUTHOR]

Acute and chronic injuries to the heart result in perturbation of intracellular calcium signaling, which leads to pathological cardiac hypertrophy and remodeling. Calcium/calmodulin-dependent protein kinase II (CaMKII) has been implicated in the transduction of calcium signals in the heart, but the specific isoforms of CaMKII that mediate pathological cardiac signaling have not been fully defined. To investigate the potential involvement in heart disease of CaMKllδ, the major CaMKII isoform expressed in the heart, we generated CaMKIIδ-null mice. These mice are viable and display no overt abnormalities in cardiac structure or function in the absence of stress. However, pathological cardiac hypertrophy and remodeling are attenuated in response to pressure overload in these animals. Cardiac extracts from CaMKIIδ-null mice showed diminished kinase activity toward histone deacetylase 4 (HDAC4), a substrate of stress-responsive protein kinases and suppressor of stress-dependent cardiac remodeling. In contrast, phosphorylation of the closely related HDAC5 was unaffected in hearts of CaMKIIδ-null mice, underscoring the specificity of the CaMKIIδ signaling pathway for HDAC4 phosphorylation. We conclude that CaMKIIδ functions as an important transducer of stress stimuli involved in pathological cardiac remodeling in vivo, which is mediated, at least in part, by the phosphorylation of HDAC4. These findings point to CaMKIIδ as a potential therapeutic target for the maintenance of cardiac function in the setting of pressure overload. [ABSTRACT FROM AUTHOR]

Objectives. Intravenous delivery of mesenchymal stem cells (MSCs) is an attractive approach for regeneration of infarcted myocardium. However, its efficacy is not well-defined in large animals. Methods. Pigs (n =8) received intravenously autologous, allogeneic porcine or human MSCs (1×106 per kg bodyweight) labeled with fluorescent dye 48 hours post proximal LAD occlusion. Infarct size, histology and myocardial function were assessed 4 weeks later. Results. Labeled MSCs migrated in the peri-infarct region resulting in improved myocardial function. Infarct size was larger in the control group (32±7%) compared to autologous (19±7%, p =0.008), allogeneic (24±4%, p =0.01) and human MSCs (26±5%, p =0.03). Fractional area shortening significantly increased after 4 weeks in pigs receiving autologous MSCs (34±7%, p =0.001), allogeneic MSCs (28±2%, p =0.004) and human MSCs (24±5%, p =0.027), but was lower in the control group (23±3%, n.s.). However, substantial callus formation and a non-malignant cardiac “tumor” containing mesenchymal tissue was observed in one animal treated with human MSCs. Conclusions. Intravenously administered MSCs prevent pathologic remodeling and scar formation but bare potential risks from inflammatory-related products. [ABSTRACT FROM AUTHOR]

We investigated tolerability and efficacy of ezetimibe treatment (10 mg/d) in 25 heart allograft recipients already on stable statin therapy. Total cholesterol (TC), low-density cholesterol (LDL-C), high-density cholesterol (HDL-C), triglycerides (TG), immunosuppressant drug levels, laboratory and clinical parameters were assessed before, four months and one yr after initiation of ezetimibe treatment. Mean equivalent statin dose was 53.5 ± 12.3 mg of pravastatin, remaining unchanged throughout the study period. Ezetimibe was generally well tolerated, only two patients (8%) discontinued ezetimibe due to stomach pain or headache. Mean TC decreased from 231.8 ± 6.4 mg/dL before therapy to 202.2 ± 8.8 mg/dL after four months and 192.9 ± 7.0 mg/dL after one yr (p < 0.001). Mean LDL-C decreased from 143.1 ± 5.4 mg/dL to 121.4 ± 7.9 mg/dL (month 4; p < 0.05) and 107.1 ± 5.6 mg/dL (one yr; p < 0.001). TG decreased from 182 ± 14.3 mg/dL to 173.3 ± 17.5 mg/dL after one yr (p < 0.05), whereas HDL-C was unchanged. Initial LDL-C and cardiac diagnosis before transplantation were identified as predictors of absolute LDL-C reduction. Immunosuppressant drug doses and blood concentrations were unchanged as well as other laboratory and clinical parameters. Ezetimibe appears safe and effective for further reduction of TC and LDL-C in heart allograft recipients already on stable statin therapy. Extent of pre-treatment LDL-C and cardiac disorder prior to transplantation appear to correlate with the efficacy of ezetimibe therapy. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the effect of bone morphogenetic protein-2 (BMP-2) and fibroblast growth factor-2 (FGF-2)— paracrine factors implicated in both cardiac embryogenesis and cardiac repair following myocardial infarction (MI)—on murine bone marrow stem cell (mBMSC) differentiation in an ex vivo cardiac microenvironment. For this purpose, green fluorescent protein (GFP) expressing hematopoietic lineage negative (lin-) c-kit ligand (c-kit) and stem cell antigen-1 (Sca-1) positive (GFP-lin-/c-kit+/sca+) mBMSC were co-cultured with neonatal rat ventricular cardiomyocytes (NVCMs). GFP+ mBMSC significantly induced the expression of BMP-2 and FGF-2 in NVCMs, and approximately 4% GFP+ mBMSCs could be recovered from the co-culture at day 10. The addition of BMP-2 in concert with FGF-2 significantly enhanced the amount of integrated GFP+ mBMSCs by 5-fold (∼20%), whereas the addition of anti-BMP-2 and/or anti-FGF-2 antibodies completely abolished this effect. An analysis of calcium cycling revealed robust calcium transients in GFP+ mBMSCs treated with BMP-2/FGF-2 compared to untreated co-cultures. BMP-2 and FGF-2 addition led to a significant induction of early (NK2 transcription factor related, locus 5; Nkx2.5, GATA binding protein 4; GATA-4) and late (myosin light chain kinase [MLC-2v], connexin 43 [Cx43]) cardiac marker mRNA expression in mBMSCs following co-culture. In addition, re-cultured fluorescence-activated cell sorting (FACS)-purified BMP-2/FGF-2-treated mBMSCs revealed robust calcium transients in response to electrical field stimulation which were inhibited by the L-type calcium channel (LTCC) inhibitor, nifedipine, and displayed caffeine-sensitive intracellular calcium stores. In summary, our results show that mBMSCs can adopt a functional cardiac phenotype through treatment with factors essential to embryonic cardiogenesis that are induced after cardiac ischemia. This study provides the first evidence that mBMSCs with long-term self-renewal potential possess the capability to serve as a functional cardiomyocyte precursor through the appropriate paracrine input and cross-talk within an appropriate cardiac microenvironment. [ABSTRACT FROM AUTHOR]

Background. Cardiac involvement in light-chain amyloidosis (AL) frequently results in heart failure with dyspnoea. In heart failure due to ischemic or idiopathic etiology, respiratory muscle dysfunction and ventilatory inefficiency contribute to symptoms and are independent prognostic predictors. However, in patients with AL, respiratory muscle function has not been elucidated. Methods. In 46 consecutive male patients with AL, lung function, maximal inspiratory (Pimax) and expiratory (Pemax) mouth occlusion pressures, cardiopulmonary exercise testing, echocardiography, and cardiac biomarkers were prospectively studied. Results. Pimax and Pemax were reduced, P0.1 did not differ between controls and AL. Pimax and Pemax were reduced in AL with congestive heart failure compared with asymptomatic patients (median (range) 5.4 (2.3-12.4) kPa vs 10.4 (6.5-14.0) kPa; p . Respiratory muscle weakness occurred in systolic and diastolic LV dysfunction. Pimax was associated with peak exercise oxygen uptake, respiratory inefficiency, wall thickness, and N-terminal pro-brain natriuretic peptide. Conclusions. Respiratory muscle dysfunction and ventilatory inefficiency correlates well with intraventricular septum thickness and peak oxygen uptake and are present even in patients with diastolic dysfunction. Respiratory muscle dysfunction might contribute to dyspnea and exercise limitation and appears to represent a marker of cardiac impairment even in diastolic heart failure. Further studies of Pimax as a potential non-invasive prognostic marker are needed. [ABSTRACT FROM AUTHOR]

The article presents information concerning clinical gene-therapy approaches in cardiology. It includes challenges in cardiovascular gene transfer, vectors for cardiac gene transfer, application systems for cardiac gene transfer, vectors for vascular gene transfer and application systems for vascular gene transfer. The positive outcome of future clinical studies will depend on the selection of appropriate patients in addition to careful consideration of the vector system and delivery mode.

A 63-year-old Caucasian male, diagnosed with dilated cardiomyopathy in 1993, remained clinically stable for several years. In 2003, a marked increase of N-terminal pro-natriuretic peptide serum level (611 ng/ml to 4926 ng/ml) was observed; left ventricular (LV) septum thickness was 10 mm. In addition, sensorimotor polyneuropathy and autonomic dysfunction occurred. Further progression of heart failure occurred despite unchanged systolic LV function. Endomyocardial biopsy in 2006 revealed transthyretin amyloidosis by Congo red and immunohistochemical staining, as well as Val94Ala substitution by transthyretin gene analysis. Cardiac amyloid deposition was quantified by technetium-99m-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) scintigraphy. Mutational search of the relatives (n = 1) was unremarkable. The transthyretin Val94Ala mutation is characterized by sensorimotor polyneuropathy, autonomic dysfunction, and gastrointestinal and cardiac involvement with amyloid. This mutation is an addition to the growing spectrum of transthyretin mutations with late onset of clinical symptoms, but noteworthy because of progressive, finally disabling disease course. Final clinical assessment of severity of cardiac involvement in the present patient is rendered complex by possible concomitant or preceding idiopathic dilated cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background: N-terminal brain-type natriuretic peptide (NT-pro BNP) and cardiac troponin T (cTnT) after acute myocardial infarction (AMI) have proven useful for prediction of prognosis and may be valuable for assessment of left ventricular function and infarct size. The aim of the present study was to correlate infarct size and left ventricular function determined by cine and late gadolinium enhanced CMR with plasma levels of TNT and NT-pro BNP levels after AMI. Methods: We studied 44 patients (pts) with first ST- and non-ST-segment elevation myocardial infarction (STEMI = 23 pts.,NSTEMI = 21 pts.). We measured NT-pro BNP and cTnT on a single occasion at 96 hours after onset of symptoms. Results: There was a moderate inverse correlation between NT-pro BNP and LV-EF in STEMI (r = -0.67, p = 0.0009) and NSTEMI (r = -0.85, p < 0.0001). Likewise, cTnT showed a significant inverse correlation with LV-EF in STEMI (r = -0.54, p = 0.014) but not in NSTEMI. With cTnT there was a strong linear correlation with infarct mass and relative infarct size in STEMI (r = 0.92, p < 0.0001) and NSTEMI (r = 0.59, p < 0.0093). NT-pro BNP demonstrated a good relationship with infarct mass (r = 0.79, p < 0.0001) and relative infarct size (r = 0.75, p < 0.0001) in STEMI, but not in NSTEMI. Conclusion: A single NT-pro BNP and cTnT value at 96 hours after onset of symptoms proved useful for estimation of LV-EF and infarct size. In direct comparison, NT-pro BNP disclosed a better performance for estimation of LV-EF whereas cTnT was superior for assessment of infarct mass and relative infarct size, suggesting an implementation of a dual marker strategy for diagnostic and prognostic work-up. [ABSTRACT FROM AUTHOR]

Abstract: Background: Patients with cardiac amyloidosis (CA) have increased mortality. Aims: Clinical, electrocardiographic, and echocardiographic parameters were assessed for risk-stratification of CA. Methods and results: CA was confirmed by endomyocardial biopsy in 59 patients (54.8±1.2 years) with light-chain (n = 43) or transthyretin amyloidosis (n = 16). Six patients without CA served as controls (NCA). Clinical symptoms, electrocardiographic, and echocardiographic parameters were analyzed for prognostic significance. Of the patients with light-chain amyloidosis, 14 died and 2 underwent heart transplantation. 1-/3-year survival was 68%/63%. Survival depended on left ventricular function (LV-EF), LV mass, radius/wall thickness, septum thickness, low voltage pattern (LVP), conduction delay, NYHA class, and stem cell transplantation. A multivariate model only contained LV-EF and LVP; the beneficial effect of stem cell transplantation was cancelled out as this treatment was withheld in patients with highest cardiac risk. Survival was most limited if both risk factors occurred. Cardiac involvement in transthyretin amyloidosis showed better survival (2 deaths, 1-/3-year survival 91%/83%). Analysis of prognostic risk factor utility in all amyloid patients (light-chain and transthyretin) again revealed LVP and LV-EF, and aetiology of amyloidosis as independent survival parameters. Conclusion: Prognosis of CA is poor, but aetiology of amyloid, LVP, and LV-EF allows identification of patients at highest risk of death, who may require individual treatment approaches (heart transplantation prior to causative therapy). [Copyright &y& Elsevier]

Background: The Roche CARDIAC proBNP point-of-care (POC) test is the first test intended for the quantitative determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) in whole blood as an aid in the diagnosis of suspected congestive heart failure, in the monitoring of patients with compensated left-ventricular dysfunction and in the risk stratification of patients with acute coronary syndromes. Methods: A multicentre evaluation was carried out to assess the analytical performance of the POC NT-proBNP test at seven different sites. Results: The majority of all coefficients of variation (CVs) obtained for within-series imprecision using native blood samples was below 10% for both 52 samples measured ten times and for 674 samples measured in duplicate. Using quality control material, the majority of CV values for day-to-day imprecision were below 14% for the low control level and below 13% for the high control level. In method comparisons for four lots of the POC NT-proBNP test with the laboratory reference method (Elecsys proBNP), the slope ranged from 0.93 to 1.10 and the intercept ranged from 1.8 to 6.9. The bias found between venous and arterial blood with the POC NT-proBNP method was ≤5%. All four lots of the POC NT-proBNP test investigated showed excellent agreement, with mean differences of between −5% and +4%. No significant interference was observed with lipaemic blood (triglyceride concentrations up to 6.3 mmol/L), icteric blood (bilirubin concentrations up to 582 μmol/L), haemolytic blood (haemoglobin concentrations up to 62 mg/L), biotin (up to 10 mg/L), rheumatoid factor (up to 42 IU/mL), or with 50 out of 52 standard or cardiological drugs in therapeutic concentrations. With bisoprolol and BNP, somewhat higher bias in the low NT-proBNP concentration range (<175 ng/L) was found. Haematocrit values between 28% and 58% had no influence on the test result. Interference may be caused by human anti-mouse antibodies (HAMA) types 1 and 2. No significant influence on the results with POC NT-proBNP was found using volumes of 140–165 μL. High NT-proBNP concentrations above the measuring range of the POC NT-proBNP test did not lead to false low results due to a potential high-dose hook effect. Conclusions: The POC NT-proBNP test showed good analytical performance and excellent agreement with the laboratory method. The POC NT-proBNP assay is therefore suitable in the POC setting. Clin Chem Lab Med 2006;44:1269–77. [ABSTRACT FROM AUTHOR]

Cardiomyopathies are complex myocardial diseases characterized by inappropriate ventricular hypertrophy (HCM) or dilation (DCM). Both disorders may lead to sudden death or progressive heart failure and exhibit familial aggregation with marked genetic heterogeneity. Many candidate genes were identified by linkage analysis, experimental animal studies, and expression analysis. A systematic assessment of the prevalence of different mutations in these genes requires high-throughput analyses. In this paper, we present a simple and reliable protocol for mutation screening by heteroduplex analysis which reduced costs and workload of sequencing. Employing denaturing gradient gel electrophoresis (DGGE), 11 known and 14 potential candidate genes for HCM and DCM were analyzed. DGGE assays allowed analysis of 286 of the 312 protein coding exons, performing only four alternative polymerase chain reaction protocols and only two different DGGE analysis conditions. Sensitivity for the detection of heteroduplexes proved excellent, even for GC-rich DNA fragments, which were analyzed by a combination of DGGE and constant denaturant gel electrophoresis. To confirm DGGE sensitivity in cases where no variants in our human DNA samples could be observed, we generated heteroduplexes from homologous human and chimpanzee DNA. The platform proved a valuable contribution to elucidating the genetic causes of DCM and HCM as demonstrated by the identification of 17 different known and novel mutations and 98 different polymorphisms in our setting. [ABSTRACT FROM AUTHOR]

The article reports on the significant use of cardiac troponin T (cTnT) or 1 (cTn1) as the preferred biochemical markers on the diagnosis of myocardial infarction (MI). The decision was made by the European Society of Cardiology and the American College of Cardiology Committee because of the high sensitivity of cTn for detection of even small amount of myocardial necrosis.

Background: The beneficial effects of β-blockers and aldosterone receptor antagonists are now well established in patients with severe systolic chronic heart failure (CHF). However, it is unclear whether β-blockers are able to provide additional benefit in patients already receiving aldosterone antagonists. We therefore examined this question in the COPERNICUS study of 2289 patients with severe CHF receiving the β1–β2/α1 blocker carvedilol compared with placebo. Methods: Patients were divided post hoc into subgroups according to whether they were receiving spironolactone (n = 445) or not (n = 1844) at baseline. Consistency of the effect of carvedilol versus placebo was examined for these subgroups with respect to the predefined end points of all-cause mortality, death or CHF-related hospitalizations, death or cardiovascular hospitalizations, and death or all-cause hospitalizations. Results: The beneficial effect of carvedilol was similar among patients who were or were not receiving spironolactone for each of the 4 efficacy measures. For all-cause mortality, the Cox model hazard ratio for carvedilol compared with placebo was 0.65 (95% CI 0.36-1.15) in patients receiving spironolactone and 0.65 (0.51-0.83) in patients not receiving spironolactone. Hazard ratios for death or all-cause hospitalization were 0.76 (0.55-1.05) versus 0.76 (0.66-0.88); for death or cardiovascular hospitalization, 0.61 (0.42-0.89) versus 0.75 (0.64-0.88); and for death or CHF hospitalization, 0.63 (0.43-0.94) versus 0.70 (0.59-0.84), in patients receiving and not receiving spironolactone, respectively. The safety and tolerability of treatment with carvedilol were also similar, regardless of background spironolactone. Conclusion: Carvedilol remained clinically efficacious in the COPERNICUS study of patients with severe CHF when added to background spironolactone in patients who were practically all receiving angiotensin-converting enzyme inhibitor (or angiotensin II antagonist) therapy. Therefore, the use of spironolactone in patients with severe CHF does not obviate the necessity of additional treatment that interferes with the adverse effects of sympathetic activation, specifically β-blockade. [Copyright &y& Elsevier]

Objective Increased dispersion (DISP) of refractoriness (ERP) facilitates the induction of malignant ventricular arrhythmias. Accordingly, QT DISP on surface ECG, supposedly reflecting ERP DISP, has been proposed as a noninvasive marker for risk stratification. However, a comparative analysis of local ERPs and QT measurements is not available so far. Methods and results In 19 healthy dogs, standard 12 lead surface ECGs were recorded to measure QT and RR intervals. Based on these measurements, corrected QT intervals (QTc, Bazett formula) and DISP (maximum difference) of both QT and QTc intervals (QT-DISP and QTc-DISP, respectively) were calculated. Subsequently, 60 custom-made needle electrodes (12 mm long, 4 bipolar electrodes per needle, interelectrode distance 2.5 mm) were inserted into the left (LV) and right ventricle (RV). At each bipole of 14 randomly selected needle electrodes (8 LV, 6 RV) local ERPs were determined (extrastimulus technique, basic cycle length 1000 ms). Interventricular DISP of ERP (LV-RV-DISP) was defined as the difference between the longest and shortest ERP within both ventricles. Respective values were calculated for each ventricle (LV-DISP; RVDISP). Scatter plots and correlation analysis did not reveal a significant correlation between QT, QTc, QT-DISP, QTc-DISP and any of the ERP measurements or calculations. Although not statistically significant, the closest correlation was found between QTc and mean ERP and between QTc-DISP and LV-RV-DISP. Conclusions QT measurements on surface ECG are poorly correlated with local ERPs. If anything, QT- or QTc-DISP might provide a rough estimate of interventricular, that is, global DISP of ERP. Local or even intraventricular DISP of ERP is definitely not reflected by these QT measurements. [ABSTRACT FROM AUTHOR]

Patients with cardiac disease typically develop life-threatening ventricular arrhythmias during physical or emotional stress, suggesting a link between adrenergic stimulation and regulation of the cardiac action potential. Human ether-a-go-go related gene (hERG) potassium channels conduct the rapid component of the repolarizing delayed rectifier potassium current, IKr. Previous studies have revealed that hERG channel activation is modulated by activation of the ß-adrenergic system. In contrast, the influence of the a-adrenergic signal transduction cascade on hERG currents is less well understood. The present study examined the regulation of hERG currents by a1A-adrenoceptors. hERG channels and human a1A-adrenoceptors were heterologously coexpressed inXenopus laevisoocytes, and currents were measured using the two-microelectrode voltage clamp technique. Stimulation of a1A-receptors by applying 20 µM phenylephrine caused hERG current reduction due to a 9.6-mV shift of the activation curve towards more positive potentials. Simultaneous application of the a1-adrenoceptor antagonist prazosin (20 µM) prevented the activation shift. Inhibition of PKC (3 µM Ro-32-0432) or PKA (2.5 µM KT 5720) abolished the a-adrenergic activation shift, suggesting that PKC and PKA are required within the regulatory mechanism. The effect was still present when the PKA- and PKC-dependent phosphorylation sites in hERG were deleted by mutagenesis. In summary, cardiac repolarizing hERG/IKr potassium currents are modulated by a1A-adrenoceptors via PKC and PKA independently of direct channel phosphorylation. This novel regulatory pathway of a1-adrenergic hERG current regulation provides a link between stress and ventricular arrhythmias, in particular in patients with heart disease. [ABSTRACT FROM AUTHOR]

Trazodone is an atypical antidepressant that is commonly used in the treatment of affective disorders. There have repeatedly been reports of cardiac arrhythmia associated with this drug and concerns have been raised regarding the cardiac safety of trazodone. However, interaction with HERG channels as a main factor of cardiac side effects has not been studied to date. Therefore, we investigated the effect of trazodone on HERG potassium channels expressed in human embryonic kidney (HEK) cells and in Xenopus oocytes. Trazodone inhibited HERG currents in a dose-dependent manner with an IC50 of 2.9 μM in HEK cells and 13.2 μM in Xenopus oocytes. The electrophysiological properties of HERG blockade were analysed in detail. In HERG channel mutants Y652A and F656A lacking aromatic residues in the S6 domain, the affinity of trazodone was reduced profoundly. Trazodone accelerated inactivation of HERG currents without markedly affecting activation. Blockade was voltage dependent with a small reduction of block at positive membrane potentials. Frequency dependence of block was not observed. Trazodone block of HERG channels was state dependent. Channels were affected in the activated and inactivated states, but not in the closed states. In summary, the atypical antidepressant trazodone blocks cardiac HERG channels at concentrations that are probably relevant in vivo, particularly in overdosage. [ABSTRACT FROM AUTHOR]

Background: Neither profiles nor prognostic value of cardiac N-terminal proBNP (NT-proBNP) have been prospectively evaluated in a sufficient number of patients with severe chronic heart failure (CHF) treated with carvedilol or placebo. Methods: Baseline and follow-up plasma concentrations of NT-proBNP were measured in the European part of the COPERNICUS Trial. This study enrolled patients with an ejection fraction <25% and symptoms of CHF at rest or on minimal exertion, equally randomized to placebo or carvedilol. Results: NT-proBNP concentrations were increased at baseline (mean±S.D.=579±822 pmol/l, median=322.5 pmol/l) with a marked decrease during follow-up in the carvedilol, but not in the placebo group. One-year mortality rates were 3.9, 12 and 27.9% in the lower, middle and upper tertiles of NT-proBNP, respectively. When mortality was calculated separately in the placebo and carvedilol group, rates were 0.8, 6.3 and 19.1% in the carvedilol treated but 6.7, 17.9 and 36.9% in the placebo treated patients. Conclusions: NT-proBNP was a powerful predictor of subsequent all-cause mortality in patients with severe CHF. This marker should therefore be further evaluated for risk stratification and monitoring of therapy in CHF. [Copyright &y& Elsevier]

Human hereditary long QT syndrome is a cardiac disease characterized by prolongation of the QT interval and increased susceptibility to ventricular arrhythmias and sudden cardiac death. Mutations in the human-ether-a-go-go-related gene (hERG), encoding the protein underlying the repolarizing cardiac IKr potassium current, cause chromosome 7-linked long QT syndrome 2. Loss of function of mutant hERG channels may be caused by several mechanisms, including altered current kinetics, altered ion selectivity, or defective intracellular protein trafficking. Especially the latter category has become a focus of particular interest recently, because some of the mutant subunits display wild type current properties when normal trafficking is restored and channels are inserted in the cell membrane in vitro. This review summarizes the current knowledge on hERG channel trafficking under physiological and pathological conditions. In addition, therapeutic approaches to restore normal hERG trafficking in vitro and in vivo are discussed. [Copyright &y& Elsevier]

Background: The prognostic role of asymptomatic nonsustained ventricular tachycardia (NSVT) and programmed ventricular stimulation (PVS) in patients with idiopathic dilated cardiomyopathy (IDC) remains controversial. Methods: The prognostic significance of ventricular arrhythmias, ejection fraction, NYHA class, atrial fibrillation and age for overall and sudden death mortality was prospectively studied in 157 patients with IDC (group 1) free of documented sustained ventricular arrhythmia and syncope. In 99 patients with asymptomatic NSVT (group 2), PVS with 2 – 3 extrastimuli was performed. Non-inducible patients were discharged without specific antiarrhythmic therapy, whereas those with inducible monomorphic ventricular tachycardia were implanted with an ICD. Results: In group 1, 48% of patients had NSVT. Overall and sudden death mortality were significantly higher in patients with NSVT (34.2 vs. 9.8%, p = 0.0001 and 15.8 vs. 3.7%, p = 0.0037; follow-up 22 ± 14 months). Multivariate analysis revealed that NSVT independently predicts both overall and sudden death mortality (p = 0.0021 and .0221, respectively; adjusted for EF, NYHA class and age). In group 2, inducibility of sustained ventricular tachyarrhythmia was 7%, but sustained monomorphic VT occurred in 3% only. Two of 7 inducible patients experienced arrhythmic events during a follow-up of 25 ± 21 months (positive predictive value 29%). Overall and sudden death mortality were 29% and 0% in the inducible group vs. 17 and 4% in the non-inducible group. Both overall and sudden death mortality were signi.cantly lower in non-inducible patients from group 2 as compared to patients from group 1 with NSVT (p = 0.0043 and 0.0048), most likely due to a more common use of betablockers and a higher EF in the former group (p < 0.001, respectively). Conclusions: In patients with IDC, NSVT independently predicts both overall and sudden death mortality. Due to a low inducibility rate and a poor positive predictive value, PVS seems inappropriate for further arrhythmia risk assessment. However, in spite of documented NSVT, the incidence of SCD in patients on optimized medical treatment including betablockers seems to be very low, questioning the need for specific arrhythmia risk stratification. [ABSTRACT FROM AUTHOR]

Context: β-Blockers remain underused despite their established utility for improving outcome in heart failure. Concerns that initiation of treatment produces few immediate benefits and may have important risks may be deterring widespread use. Objective: To evaluate the early effects of the β-blocker carvedilol in patients with severe heart failure. Design, Setting, and Patients: Randomized, double-blind, placebo-controlled trial conducted from October 28, 1997, to March 20, 2000, at 334 hospital centers in 21 countries among 2289 patients with symptoms of heart failure at rest or with minimal exertion who were clinically euvolemic and had a left ventricular ejection fraction of less than 25%. Intervention: Patients were randomly assigned to receive carvedilol, with start dosage of at 3.125 mg twice daily with uptitration to a target dosage of 25 mg twice daily (n = 1156), or placebo (n = 1133), in addition to their usual medications for heart failure. Main Outcome Measures: Death, hospitalization, or permanent withdrawal from study drug, as well as adverse events during the first 8 weeks of treatment. Results: The carvedilol group experienced no increase in cardiovascular risk but instead had fewer patients who died (19 vs 25; hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.41-1.35); who died or were hospitalized (134 vs 153; HR, 0.85; 95% CI, 0.67-1.07); or who died, were hospitalized, or were permanently withdrawn from treatment (162 vs 188; HR, 0.83; 95% CI, 0.68-1.03). These effects were similar in direction and magnitude to those observed during the entire study, and were apparent particularly in the 624 patients with recent or recurrent decompensation or a very depressed left ventricular ejection fraction. Differences in favor of carvedilol became apparent as early as 14 to 21 days following initiation of treatment. Worsening heart failure was the only serious adverse event with a frequency greater than 2% and was reported with... [ABSTRACT FROM AUTHOR]

Background: Reopening of the infarct-related coronary artery is the treatment of choice in the clinical setting of acute myocardial infarction. Nevertheless the removal of the total occlusion obtained either by thrombolysis or by primary angioplasty is followed by the ischemia/reperfusion sequelae. One of many proposed mechanisms playing a role in ischemia/reperfusion damage is a persistent increase in vasoconstrictor tone, which reduces cardiac function and impairs myocardial blood flow during primary percutaneous coronary intervention in acute myocardial infarction (PAMI). Methods: To investigate early neurohumoral changes during PAMI we enrolled 18 patients, who were collated to 13 patients with stable angina undergoing elective PTCA. To evaluate angiotensin II (AngII), endothelin-1 (ET-1), vasopressin (AVP), norepinephrine (NE), troponin T (TNT), creatinephosphate kinase (CPKM) and isoenzyme MB (CPKMB), we collected blood from the pulmonary artery before and immediately after the infarct-related artery (IRA; TIMI 0 → 2–3) or culprit lesion revascularization. Hemodynamic and angiographic LV-function parameters were compared to biochemical data. Corrected TIMI-frame count (CTFC) was used as an index of coronary blood flow and correlated to the biochemical measurements. Results: CTFC in the IRA correlated inversely (p = 0.03; r = -0.51) with left ventricular ejection fraction measured after 10 days, and positively (p = 0.03; r = 0.54) with the maximal amount of LDH released after onset of AMI. There was an abrupt and long lasting rise in ET-1 (+65 %; p < 0.001) and an instant short lasting increase in AVP (+37 %; p < 0.05), whereas NE concentrations were elevated prior to PAMI and remained elevated during reperfusion. Correlations with CTFC were found for ET-1 (p = 0.01; r = 0.61) and NE (p = 0.01; r = 0.58) during reperfusion. The extent of left ventricular dysfunction correlated with the concentrations of AVP and NE during reperfusion. Conclusions: There is evidence for a distinct pattern of neurohumoral activation during early reperfusion in acute myocardial infarction. In particular, we documented substantial increases in AVP and ET-1. Left ventricular wall-stress appears to be involved in the release of AVP. Elevated levels of ET-1 and NE are associated with impaired angiographic reperfusion and increased myocardial damage after mechanical recanalization. [ABSTRACT FROM AUTHOR]

A 3-h algorithm using high-sensitivity assays for cardiac troponin to rule out myocardial infarction (MI) is recommended in current ESC guidelines. Whether faster rule-out algorithms can discriminate between MI and other conditions that elevate the troponin level, or be safely implemented across the whole spectrum of patient risk, is unclear. [ABSTRACT FROM AUTHOR]

This case report describes a patient with complete AV block and a VDD pacemaker who experienced repetitive episodes of symptomatic bradycardia. Episodes occurred due to activation of an automatic beat-to-beat mode switch algorithm. After mode switch to VDI operation. the pacemaker failed to immediately switch back to AV synchronous pacing when regular sinus rhythm (≥ 100 beats per minute) resumed despite adequate P wave sensing. Dizziness was felt for tip to several minutes of asynchronous Pacing at the lower rate limit until VDD mode was restored. Episodes were completely eliminated by programming the mode switch function from an automatic beat-to-beat algorithm to a fixed rate algorithm. [ABSTRACT FROM AUTHOR]

The author opines on the role of autoimmunity in dilated cardiomyopathy (DCM) with reference to an article within this issue. He believes that though the role of autoimmunity in heart failure is still unclear, research in this field can provide the evidence that autoantibodies do exist in some DCM patients and contribute to disease progression in such patients. He stresses upon the need to have large multicenter trials to help study the clinical significance of autoimmune responses and autoantibodies in DCM patients.

Abstract: We present a curious pulsatile right atrial mass which we found by routine transthoracic echocardiography in an asymptomatic woman. Only consecutive section planes finally revealed the true nature of this round mass, highlighting the general statement that the ultrasonographer should never rely on a single ultrasound imaging plane for making a correct diagnosis. [Copyright &y& Elsevier]

Background: In the era of early reperfusion therapy, life-threatening ventricular arrhythmias (VA) remain common after recanalization of an occluded coronary artery. Experimental studies reported that angiotensin-converting (ACE) inhibitors suppress reperfusion-induced VA. However, whether ACE inhibitors lower the incidence of reperfusion clinical VA is unknown. We examined the effects of low doses of intracoronary (i.c.) enalaprilat (EN) as an adjunct to direct percutaneous coronary interventions (PCI) on reperfusion VA in the acute phase of myocardial infarction (MI). Methods: We randomly assigned 22 patients with a first acute MI, who underwent successful direct PCI, to EN, 50 μg, i.c., or placebo (PL), administered immediately after reperfusion. VA were manually edited and counted from 24-hour Holter recordings begun upon hospital admission. Results: There were no significant between-groups differences in clinical characteristics. Mean RR interval before and after PCI, and the incidence of VA before PCI were similar in both groups. After PCI the incidence of reperfusion-induced VA was significantly lower in the EN-treated group (VPB/h: PL 29.9 ± 12 vs EN 43.2 ± 42, P < 0.05; couplets/h: EN 0.9 ± 0.7 vs PL 4.1 ± 5.0, P < 0.01; triplets/h: EN 0.3 ± 0.2 vs PL 1.2 ± 1.5, P < 0.05; ventricular tachycardia/h: EN 0.3 ± 0.1 vs PL 0.8 ± 0.5, P < 0.01). Conclusions: Compared with PL, i.c. EN significantly lowered the incidence of reperfusion-associated VA. This previously unrecognized antiarrhythmic effect might be an important therapeutic benefit conferred by ACE inhibitors, beyond limitation of infarct size. [ABSTRACT FROM AUTHOR]

Background: Assessment of myocardial blood flow is important for identification and monitoring of microvascular effects of glycoprotein IIb/IIIa inhibitors. Magnetic resonance imaging is a novel noninvasive method providing complementary information on myocardial blood flow and cardiac function. Methods and Results: Patients (n = 53) admitted within 12 (mean, 5.8) hours after onset of symptoms were randomized to tirofiban or standard therapy before primary percutaneous coronary intervention (PCI) with stenting. Myocardial blood flow was graded by measurement of corrected Thrombolysis in Myocardial Infarction frame counts and by semiquantitative analysis of signal intensity curves from first-pass contrast-enhanced magnetic resonance perfusion. Pretreatment with tirofiban proved safe and resulted in a significantly lower corrected Thrombolysis in Myocardial Infarction frame counts (21 vs 34, P = .008) indicating improved myocardial blood flow. Magnetic resonance imaging revealed higher normalized peak signal intensities (2.19 vs 1.63, P = .046) and a trend to steeper upslopes (0.79 vs 0.48, P = .1). Cardiac left ventricular wall motion analysis resulted in a significantly lower number of myocardial segments with abnormal wall thickening (6.4 vs 8.5, P = .025). Conclusions: Pretreatment with tirofiban appears safe and improves myocardial flow after primary PCI with stenting. Magnetic resonance imaging proved useful as a complementary method for noninvasive assessment of myocardial blood flow and cardiac function in patients with ST-segment elevation myocardial infarction undergoing primary PCI. [Copyright &y& Elsevier]

Hypertrophic cardiomyopathy (HCM) is the most-common monogenically inherited form of heart disease, characterized by thickening of the left ventricular wall, contractile dysfunction, and potentially fatal arrhythmias. HCM is also the most-common cause of sudden cardiac death in individuals younger than 35 years of age. Much progress has been made in the elucidation of the genetic basis of HCM, resulting in the identification of more than 900 individual mutations in over 20 genes. Interestingly, most of these genes encode sarcomeric proteins, such as myosin-7 (also known as cardiac muscle β-myosin heavy chain; MYH7), cardiac myosin-binding protein C (MYBPC3), and cardiac muscle troponin T (TNNT2). However, the molecular events that ultimately lead to the clinical phenotype of HCM are still unclear. We discuss several potential pathways, which include altered calcium cycling and sarcomeric calcium sensitivity, increased fibrosis, disturbed biomechanical stress sensing, and impaired cardiac energy homeostasis. An improved understanding of the pathological mechanisms involved will result in greater specificity and success of therapies for patients with HCM. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most frequent sustained arrhythmia and can lead to structural cardiac changes, known as tachycardia-induced cardiomyopathy (TIC). HCN4 is implicated in spontaneous excitation of the sinoatrial node, while channel dysfunction has been associated with sinus bradycardia, AF and structural heart disease. We here asked whether HCN4 mutations may contribute to the development of TIC, as well. Mutation scanning of HCN4 in 60 independent patients with AF and suspected TIC followed by panel sequencing in carriers of HCN4 variants identified the HCN4 variant P883R [minor allele frequency (MAF): 0,88%], together with the KCNE1 variant S38G (MAF: 65%) in three unrelated patients. Family histories revealed additional cases of AF, sudden cardiac death and cardiomyopathy. Patch-clamp recordings of HCN4-P883R channels expressed in HEK293 cells showed remarkable alterations of channel properties shifting the half-maximal activation voltage to more depolarized potentials, while channel deactivation was faster compared to wild-type (WT). Co-transfection of WT and mutant subunits, resembling the heterozygous cellular situation of our patients, revealed significantly higher current densities compared to WT. In conclusion HCN4-P883R may increase ectopic trigger and maintenance of AF by shifting the activation voltage of I f to more positive potentials and producing higher current density. Together with the common KCNE1 variant S38G, previously proposed as a genetic modifier of AF, HCN4-P883R may provide a substrate for the development of AF and TIC. • HCN4 -P883R is linked to atrial fibrillation and tachycardia-induced cardiomyopathy. • Activation of P883R channels is shifted to depolarized potentials. • Deactivation of P883R channels is faster compared to wild-type. • Heteromeric P883R/wild-type channels reveal increased current density. • P883R may provide a substrate for AF-associated structural heart disease. [ABSTRACT FROM AUTHOR]

Background Disease-independent sources of biomarker variability include pre-analytical, analytical and biological variance. The aim of the present study was to evaluate whether the pre-analytical phase has any impact on the emerging heart disease TWEAK and HMGB1 protein markers and miRNA biomarkers, and whether peptidome profiling allows the identification of pre-analytical quality markers. Methods An assessment was made of sample type (serum, EDTA-Plasma, Citrate-Plasma, ACD-plasma, Heparin-plasma), temperature of sample storage (room temperature or refrigerated), time of sample storage (0.5, 3, 6 and 9 h) and centrifugation (one or two-step). Aliquots of all processed samples were immediately frozen (− 80 °C) before analysis. Proteins were assayed by ELISAs, miRNA expression profile by microarray and peptidome profiling by MALDI-TOF/MS. Results Temperature, time and centrifugation had no impact on TWEAK and HMGB1 results, which were significantly influenced by matrix type, TWEAK levels being significantly higher (F = 194.7, p < 0.0001), and HMGB1 levels significantly lower (F = 36.32, p < 0.0001) in serum than in any other plasma type. Unsuitable miRNA results were obtained using Heparin-plasma. Serum miRNA expression profiles depended mainly on temperature, while EDTA-plasma miRNA expression profiles were strongly affected by the centrifugation method used. MALDI-TOF/MS allowed the identification of seven features as indices of pre-analytical serum ( m / z at 1206, 1350, 1865 and 2021) or EDTA-plasma ( m / z 1897, 2740 and 2917) degradation. Conclusions Serum and EDTA-plasma allow the analysis of both proteins and miRNA emerging biomarkers of heart diseases. Refrigerated storage prevents an altered miRNA expression profile also in cases of a prolonged time-interval between blood drawing and processing. [ABSTRACT FROM AUTHOR]

Background--Ticagrelor, when compared with clopidogrel, reduced the 12-month risk of vascular death/myocardial infarction and stroke in patients with ST-elevation acute coronary syndromes intended to undergo primary percutaneous coronary intervention in the PLATelet inhibition and patient Outcomes (PLATO) trial. This prespecified ECG substudy explored whether ticagrelor's association with vascular death and myocardial infarction within 1 year would be amplified by (1) the extent of baseline ST shift and (2) subsequently associated with fewer residual ST changes at hospital discharge. Methods and Results--ECGs were evaluated centrally in a core laboratory in 3122 ticagrelor- and 3084 clopidogrel-assigned patients having at least 1 mm ST-elevation in 2 contiguous leads as identified by site investigators on the qualifying ECG. Patients with greater ST-segment shift at baseline had higher rates of vascular death/myocardial infarction within 1 year. Among those who also had an ECG at hospital discharge (n=4798), patients with ≥50% ΣST-deviation (ΣST-dev) resolution had higher event-free survival than those with incomplete resolution (6.4% versus 8.8%, adjusted hazard ratio 0.69 (0.54-0.88), P=0.003). The extent of ΣST-dev resolution was similar irrespective of treatment assignment. The benefit of ticagrelor versus clopidogrel on clinical events was consistent irrespective of the extent of baseline ΣST-dev (P(interaction) =0.728). When stratified according to conventional times from symptom onset, ie, ≤3 hours, 3 to 6 hours, >6 hours, the extent of baseline ΣST-dev declined progressively over time. As time from symptom onset increased beyond 3 hours, the benefit of ticagrelor appeared to be more pronounced; however, the interaction between time and treatment was not significant (P=0.175). Conclusions--Ticagrelor did not modify ΣST-dev resolution at discharge nor was its benefit affected by the extent of baseline ΣST-dev. These hypothesis-generating observations suggest that the main effects of ticagrelor may not relate to the rapidity or the completeness of acute reperfusion, but rather the prevention of recurrent vascular events by more powerful platelet inhibition or other mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Our objective was to assess the prevalence of panic disorder, its influence on quality of life (QoL), and the presence of further anxiety and depressive comorbid disorders in outpatients with chronic heart failure (CHF). Methods: In a cross-sectional study, anxiety and depressive disorders were diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition diagnostic criteria in patients with CHF who were aged ≥18 years and had New York Heart Association (NYHA) Functional Classes I–IV, using the Patient Health Questionnaire. Health-related QoL was evaluated using the Short-Form 36 Health Survey (SF-36). Results: Of the 258 participating patients, 24 (9.3%) fulfilled diagnostic criteria for panic disorder. Seven of these (29.2%) were diagnosed with comorbid anxiety disorders, 11 (47.3%) were diagnosed with comorbid depressive disorder, and 5 (20.8%) were diagnosed with other anxiety disorders and any depressive disorder. Female gender [odds ratio (OR)=3.1; 95% confidence interval (95% CI)=1.2–7.8; P=.02] and a lower level of education (OR=0.3; 95% CI=0.1–0.9; P=.04) were associated with the presence of panic disorder. In patients with panic disorder, QoL was significantly more restricted on all subscales of the SF-36 as compared to those without panic disorder, even when age, gender, and NYHA functional class were controlled for (P=.05 to <.01). Conclusion: Approximately 1 of 10 patients with CHF suffers from panic disorder, many of whom also have additional anxiety or depressive comorbid disorders. Female gender and a low level of education are positively associated with the presence of panic disorder. QoL is severely limited by the presence of panic disorder. Diagnosis of mental disorders and treatment offers for affected patients should be available in patient care. [Copyright &y& Elsevier]

Abstract: The antihypertensive drug doxazosin has been associated with an increased risk for congestive heart failure and cardiomyocyte apoptosis. Human ether-a-go-go-related gene (hERG) K+ channels, previously shown to be blocked by doxazosin at therapeutically relevant concentrations, represent plasma membrane receptors for the antihypertensive drug. To elucidate the molecular basis for doxazosin-associated pro-apoptotic effects, cell death was studied in human embryonic kidney cells using three independent apoptosis assays. Doxazosin specifically induced apoptosis in hERG-expressing HEK cells, while untransfected control groups were insensitive to treatment with the antihypertensive agent. An unexpected biological mechanism has emerged: binding of doxazosin to its novel membrane receptor, hERG, triggers apoptosis, possibly representing a broader pathophysiological mechanism in drug-induced heart failure. [Copyright &y& Elsevier]

Left ventricular electromechanical asynchrony has been shown to predict cardiac events in patients with heart failure. This study investigated whether left ventricular asynchrony is present in patients with type 2 diabetes mellitus (DM) with no clinically evident heart disease and normal QRS durations. Asynchrony was evaluated in 24 patients with DM, 15 nondiabetic control subjects, and 20 patients with left bundle branch block (LBBB) due to cardiomyopathy serving as positive controls by conventional tissue Doppler imaging and by a novel method, echocardiographic phase imaging. Asynchrony was significantly higher in patients with DM than in controls and significantly lower than in patients with LBBB. This was shown by tissue Doppler imaging: the SD of time to peak myocardial velocity was 13 ± 10 ms in controls, compared with 30 ± 19 ms in patients with DM (p <0.01) and 68 ± 28 ms in those with LBBB (p <0.001). Similar data were obtained using echocardiographic phase imaging: the SD of phase degrees was 25° ± 8° in controls, compared with 44° ± 21° in patients with DM (p = 0.02) and 76° ± 25° in those with LBBB (p <0.001). Tissue Doppler imaging correlated with echocardiographic phase imaging (r = 0.79, p <0.0001) but was more time consuming (15.5 ± 4.5 vs 4.5 ± 2.2 min/patient, p <0.05) and showed higher intraobserver variability (5.6% vs 3.2%, p <0.05). In conclusion, this is the first study showing increased left ventricular asynchrony in patients with DM and no clinical evidence of heart disease. [Copyright &y& Elsevier]

Abstract: Myocardial infarction (MI) represents an enormous clinical challenge as loss of myocardium due to ischemic injury is associated with compromised left ventricular (LV) function often leading to acute cardiac decompensation or chronic heart failure. S100A1 was recently identified as a positive inotropic regulator of myocardial contractility in vitro and in vivo. Here, we explore the strategy of myocardial S100A1 gene therapy either at the time of, or 2 h after, MI to preserve global heart function. Rats underwent cryothermia-induced MI and in vivo intracoronary delivery of adenoviral transgenes (4 × 1010 pfu). Animals received saline (MI), the S100A1 adenovirus (MI/AdS100A1), a control adenovirus (MI/AdGFP), or a sham operation. S100A1 gene delivery preserved global in vivo LV function 1 week after MI. Preservation of LV function was due mainly to S100A1-mediated gain of contractility of the remaining, viable myocardium since contractile parameters and Ca2+ transients of isolated MI/AdS100A1 myocytes were significantly enhanced compared to myocytes isolated from both MI/AdGFP and sham groups. Moreover, S100A1 gene therapy preserved the cardiac β-adrenergic inotropic reserve, which was associated with the attenuation of GRK2 up-regulation. Also, S100A1 overexpression reduced cardiac hypertrophy 1 week post-MI. Overall, our data indicate that S100A1 gene therapy provides a potential novel treatment strategy to maintain contractile performance of the post-MI heart. [Copyright &y& Elsevier]

Cardiac-restricted overexpression of the Ca2+-binding protein S100A1 has been shown to lead to increased myocardial contractile performance in vitro and in vivo. Since decreased cardiac expression of S100A1 is a characteristic of heart failure, we tested the hypothesis that S100A1 gene transfer could restore contractile function of failing myocardium. Adenoviral S100A1 gene delivery normalized S100A1 protein expression in a postinfarction rat heart failure model and reversed contractile dysfunction of failing myocardium in vivo and in vitro. S100A1 gene transfer to failing cardiomyocytes restored diminished intracellular Ca2+ transients and sarcoplasmic reticulum (SR) Ca2+ load mechanistically due to increased SR Ca2+ uptake and reduced SR Ca2+ leak. Moreover, S100A1 gene transfer decreased elevated intracellular Na+ concentrations to levels detected in nonfailing cardiomyocytes, reversed reactivated fetal gene expression, and restored energy supply in failing cardiomyocytes. Intracoronary adenovirus-mediated S100A1 gene delivery in vivo to the postinfarcted failing rat heart normalized myocardial contractile function and Ca2+ handling, which provided support in a physiological context for results found in myocytes. Thus, the present study demonstrates that restoration of S100A1 protein levels in failing myocardium by gene transfer may be a novel therapeutic strategy for the treatment of heart failure. [ABSTRACT FROM AUTHOR]

: ObjectivesWe sought to evaluate the influence of pretreatment systolic blood pressure (SBP) on the efficacy and safety of carvedilol in patients with chronic heart failure (CHF).: BackgroundAlthough beta-blockers reduce the risk of death in CHF, there is little reported experience with these drugs in patients with a low pretreatment SBP, who may respond poorly to beta-blockade.: MethodsWe studied 2,289 patients with severe CHF who participated in the Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS) trial.: ResultsCompared with placebo, carvedilol improved the clinical status and reduced the risk of death and the combined risk of death or hospitalization for any reason, for a cardiovascular reason, or for worsening heart failure (p < 0.001 for all). The relative magnitude of these benefits did not vary as a function of the pretreatment SBP (all interaction: p > 0.10). However, because patients with the lowest SBP were at highest risk of an event, they experienced the greatest absolute benefit from treatment with carvedilol. The lower the pretreatment SBP, the more likely that patients would report an adverse event, be intolerant of high doses of the study drug, or require permanent withdrawal of treatment (p < 0.001 for all). However, these risks were primarily related to the severity of the underlying illness and not to treatment with carvedilol.: ConclusionsThe current study provides little support for concerns about using beta-blockers (particularly those with vasodilatory actions) in patients with severe CHF who have a low SBP. Pretreatment blood pressure can identify patients who have the greatest need for risk reduction with carvedilol. [Copyright &y& Elsevier]

Background: Beta-blocking agents reduce the risk of hospitalization and death in patients with mild-to-moderate heart failure, but little is known about their effects in severe heart failure. Methods: We evaluated 2289 patients who had symptoms of heart failure at rest or on minimal exertion, who were clinically euvolemic, and who had an ejection fraction of less than 25 percent. In a double-blind fashion, we randomly assigned 1133 patients to placebo and 1156 patients to treatment with carvedilol for a mean period of 10.4 months, during which standard therapy for heart failure was continued. Patients who required intensive care, had marked fluid retention, or were receiving intravenous vasodilators or positive inotropic drugs were excluded. Results: There were 190 deaths in the placebo group and 130 deaths in the carvedilol group. This difference reflected a 35 percent decrease in the risk of death with carvedilol (95 percent confidence interval, 19 to 48 percent; P=0.0014, adjusted for interim analyses). A total of 507 patients died or were hospitalized in the placebo group, as compared with 425 in the carvedilol group. This difference reflected a 24 percent decrease in the combined risk of death or hospitalization with carvedilol. The favorable effects on both end points were seen consistently in all the subgroups we examined. Fewer patients in the carvedilol group than in the placebo group withdrew because of adverse effects or for other reasons (P=0.02). Conclusions: The previously reported benefits of carvedilol with regard to morbidity and mortality in patients with mild-to-moderate heart failure were also found in the patients with severe heart failure who were evaluated in this trial. (N Engl J Med 2001;344:1651-8.) [ABSTRACT FROM AUTHOR]