Daniele Masarone

Novel insights into the role of cardiotrophin-1 in cardiovascular diseases

Cardiotrophin-1 (CT-1), a member of interleukin (IL)-6 family, was originally isolated for its ability to induce a hypertrophic response in neonatal cardiac myocytes. This cytokine mediates a pleiotropic set of growth and differentiation activities through a unique receptor system, consisting of IL-6 receptor (IL-6R) and a common signal transducer, the glycoprotein 130 (gp130). Both in humans and in mice, CT-1 mRNA has been detected in several tissues, such as liver tissue, adipose tissue, and tissues in the respiratory and nervous systems; in each of these tissues it performs different functions. Predominant actions of CT-1 are on the heart, where it is synthesized and where it provides first myocardial protection by promoting cell survival and proliferation, it carries on its haemodynamic effects and endocrine properties, and finally, it predisposes the heart to pathological conditions. The aim of this review is to describe the pathophysiological mechanisms through which CT-1 carries out its activities, especially on the heart, and its potential contribution as a disease marker in clinical cardiology. Recent studies have confirmed its active role in promoting structural changes typical of most common cardiovascular disease, such as hypertension, valve diseases, congestive heart failure, and coronary artery disease. In fact, CT-1 induces myocyte hypertrophy and collagen synthesis, thereby participating in the progression of ventricular remodelling, which results in cardiac muscle failure at the latest stage. CT-1 plasma levels are elevated in patients with hypertension and coronary artery diseases, and they are also correlated with the severity of valve diseases and heart failure. Therefore, CT-1 may represent a diagnostic, staging, and prognostic biomarker of cardiovascular diseases.

Mitochondrial diseases and the heart: an overview of molecular basis, diagnosis, treatment and clinical course

The mitochondrion is the main site of production of ATP that represents the source of energy for a large number of cellular processes. Mitochondrial diseases that result in a deficit in ATP production can affect almost every organ system with a large spectrum of clinical phenotypes. Cardiomyocytes are particularly vulnerable to limited ATP supply because of their large energy requirement. Abnormalities in the mitochondrial function are increasingly recognized in association with dilated and hypertrophic cardiomyopathy, cardiac conduction defects, endothelial dysfunction and coronary artery disease. Cardiologists should, therefore, be alerted to symptoms and signs suggestive of mitochondrial diseases and become familiar with the general issues related to multisystem disease management, genetic counseling and testing.

Renal Function and Peak Exercise Oxygen Consumption in Chronic Heart Failure With Reduced Left Ventricular Ejection Fraction

BACKGROUND Chronic kidney disease is associated with sympathetic activation and muscle abnormalities, which may contribute to decreased exercise capacity. We investigated the correlation of renal function with peak exercise oxygen consumption (V̇O2) in heart failure (HF) patients. METHODS AND RESULTS: We recruited 2,938 systolic HF patients who underwent clinical, laboratory, echocardiographic and cardiopulmonary exercise testing. The patients were stratified according to estimated glomerular filtration rate (eGFR). Mean follow-up was 3.7 years. The primary outcome was a composite of cardiovascular death and urgent heart transplantation at 3 years. On multivariable regression, eGFR was predictor of peakV̇O2(P<0.0001). Other predictors were age, sex, body mass index, HF etiology, NYHA class, atrial fibrillation, resting heart rate, B-type natriuretic peptide, hemoglobin, and treatment. After adjusting for significant covariates, the hazard ratio for primary outcome associated with peakV̇O2<12 ml·kg(-1)·min(-1)was 1.75 (95% confidence interval (CI): 1.06-2.91; P=0.0292) in patients with eGFR ≥60, 1.77 (0.87-3.61; P=0.1141) in those with eGFR of 45-59, and 2.72 (1.01-7.37; P=0.0489) in those with eGFR <45 ml·min(-1)·1.73 m(-2). The area under the receiver-operating characteristic curve for peakV̇O2<12 ml·kg(-1)·min(-1)was 0.63 (95% CI: 0.54-0.71), 0.67 (0.56-0.78), and 0.57 (0.47-0.69), respectively. Testing for interaction was not significant. CONCLUSIONS Renal dysfunction is correlated with peakV̇O2. A peakV̇O2cutoff of 12 ml·kg(-1)·min(-1)offers limited prognostic information in HF patients with more severely impaired renal function.

Takotsubo Cardiomyopathy Do the Genetics Matter

Takotsubo cardiomyopathy (TTC) is an enigmatic disease with a multifactorial and still unresolved pathogenesis. Recent experimental and clinical observation has suggested a role for genetics in the pathogenesis of TTC. Ethnic as well as seasonal variation in the prevalence of TTC is well described, but it is only recently that familial cases of TTC have been reported. In recent years technological advances in exome capture and DNA sequencing have offered clinicians a new opportunity to discover genetics-related disease. This article explores the role of genetic mechanisms that might explain or modulate the pathogenesis of TTC.

Right Ventricular Cardiomyopathies: A Multidisciplinary Approach to Diagnosis

The physiological importance of the right ventricle (RV) has been underestimated over the past years. Finally in the early 1950s through the 1970s, cardiac surgeons recognized the importance of RV function. Since then, the importance of RV function has been recognized in many acquired cardiac heart disease. RV can be mainly or together with left ventricle (LV) affected by inherited or acquired cardiomyopathy. In fact, RV morphological and functional remodeling occurs more common during cardiomyopathies than in ischemic cardiomyopathies and more closely parallels LV dysfunction.

Cardiotrophin-1 and TNF-α circulating levels at rest and during cardiopulmonary exercise test in athletes and healthy individuals

BACKGROUND There is a growing body of evidence that physical training exerts its potential benefits on the individual health status by modulating the immune system and the whole body metabolism. A better knowledge of the physiologic immune response to exercise may help to understand the benefits of physical exercise in healthy individuals and elite athletes. AIMS This study aims to analyse cardiotrophin-1 (CT-1) and Tumor Necrosis Factor-alpha (TNF-alpha) plasma levels at rest and during exercise in elite athletes and healthy controls. METHODS We studied 20 triathletes (TA) and 20 matched controls (CG). Chambers dimensions, left ventricular mass and left ventricular mass index were analysed by echocardiography. VO2 peak and VE/VCO2 were calculated by metabolic stress test. Blood samples were collected before the exercise session, at the exercise peak, and after the end of exercise. ELISA assays were used to measure CT-1 and TNF-alpha plasma levels. RESULTS Among TA and CG, no significant differences were found for CT-1 (0.25+/-0.14 vs 0.20+/-0.14 fm/l; p=0.29) and TNF-alpha (10.8+/-2.7 vs 9.7+/-4.0 pm/l; p=0.29) basal levels. In the TA, plasma levels of CT-1 were significantly different at rest and during exercise (basal 0.25+/-0.13 pm/l; peak 1.07+/-1.5 pm/l; post-exercise 0.67+/-0.77 pm/l; p=0.04). Conversely, no significant differences were found between basal, peak and post-exercise plasma values of TNF-alpha (basal 10.8+/-2.7 pm/l; peak 11.7+/-2.1 pm/l; post-exercise 11.4+/-2.5 pm/l; p=0.78) in TA. CONCLUSIONS This study gives novel insights on the behavior of inflammatory cytokines during physical exercise in athletes and healthy individuals.

Prognostic role of atrial fibrillation in patients affected by chronic heart failure. Data from the MECKI score research group

BACKGROUND Atrial fibrillation (AF) is common in heart failure (HF). It is unclear whether AF has an independent prognostic role in HF. The aim of the present study was to assess the prognostic role of AF in HF patients with reduced ejection fraction (EF). METHODS HF patients were followed in 17 centers for 3.15years (1.51-5.24). Study endpoints were the composite of cardiovascular (CV) death and heart transplant (HTX) and all-cause death. Data analysis was performed considering the entire population and a 1 to 1 match between sinus rhythm (SR) and AF patients. Match process was done for age±5, gender, left ventricle EF±5, peakVO2±3 (ml/min/kg) and recruiting center. RESULTS A total of 3447 patients (SR=2882, AF=565) were included in the study. Considering the entire population, CV death and HTX occurred in 114 (20%) AF vs. 471 (16%) SR (p=0.026) and all-cause death in 130 (23%) AF vs. 554 (19.2%) SR patients (p=0.039). At univariable Cox analysis, AF was significantly related to prognosis. Applying a multivariable model based on all variables significant at univariable analysis (EF, peakVO2, ventilation/carbon dioxide relationship slope, sodium, kidney function, hemoglobin, beta-blockers and digoxin) AF was no longer associated with adverse outcomes. Matching procedure resulted in 338 couples. CV death and HTX occurred in 63 (18.6%) AF vs. 74 (21.9%) SR (p=0.293) and all-cause death in 71 (21%) AF vs. 80 (23.6%) SR (p=0.406), with no survival differences between groups. CONCLUSION In systolic HF AF is a marker of disease severity but not an independent prognostic indicator.

Natriuretic peptides: molecular biology, pathophysiology and clinical implications for the cardiologist

Natriuretic peptides (NPs) counter the effects of volume overload or adrenergic activation of the cardiovascular system. They are able to induce arterial vasodilatations, natriuresis and diuresis, and they reduce the activities of the renin-angiotensin-aldosterone system and the sympathetic nervous system. However, in addition to wall stress, other factors have been associated with elevated natriuretic peptide levels. Since 2000, because of their characteristics, NPs have become quantitative plasma biomarkers of heart failure. Nowadays, NPs play an important role not only in the diagnosis of heart failure, but also for a prognostic purpose and a guide to medical therapy. Finally, a new drug that modulates the NP system or recombinant analogs of NPs are now available in patients with heart failure.

Right ventricular hypertrabeculation associated with double-outlet left ventricle: exaggeration of a normal pattern or right ventricular cardiomyopathy?

We describe a rare case of double-outlet left ventricle, ventricular septal defect, and subpulmonary valve stenosis surgically corrected by Rastelli procedure, developing severe homograft obstruction with right ventricular dilation and extensive hypertrabeculation/noncompaction during follow-up. We briefly discuss the cause diagnosis, and clinical significance of right ventricular hypertrabeculation/noncompaction.

Pediatric Heart Failure: A Practical Guide to Diagnosis and Management

Pediatric heart failure represents an important cause of morbidity and mortality in childhood. Currently, there are well-established guidelines for the management of heart failure in the adult population, but an equivalent consensus in children is lacking. In the clinical setting, ensuring an accurate diagnosis and defining etiology is essential to optimal treatment. Diuretics and angiotensin-converting enzyme inhibition are the first-line therapies, whereas beta-blockers and devices for electric therapy are less used in children than in adults. In the end-stage disease, heart transplantation is the best choice of treatment, while a left ventricular assist device can be used as a bridge to transplantation (due to the difficulties in finding organ donors), recovery (in the case of myocarditis), or destination therapy (for patients with systemic disease).