293 research outputs found
Chronotropic Incompentence and Functional Capacity in CHF
SUMMARY Aim: To assess the effect of chronotropic incompetence on functional capacity in chronic heart failure (CHF) patients, as evaluated as NYHA and peak oxygen consumption (pVO2), focusing on the presence and dose of β-blocker treatment. Methods: Nine hundred and sixty-seven consecutive CHF patients were evaluated, 328 of whom were discarded because they failed to meet the study criteria. Of the 639 analyzed, 90 were not treated with β-blockers whereas the other 549 were. The latter were further subdivided in high (n = 184) and low (n = 365) β-blockers daily dose group in accordance with an arbitrary cut-off of 25 mg for carvedilol and of 5 mg for bisoprolol. Failure to achieve 80% of the percentage of maximum age predicted peak heart rate (%Max PHR) or of HR reserve (%HRR) constituted chronotropic incompetence. Results: No differences were found in NYHA or pVO2 between patients with and without β-blockers and, similarly, between high and low β-blocker dose groups. Twenty and sixty-nine percent of not β-blocked patients showed chronotropic incompetence according to %Max PHR and %HRR, respectively, whereas this prevalence rose to 61% and 84% in those on β-blocker therapy. Patients taking β-blockers without chronotropic incompetence, as inferable from both %Max PHR and %HRR, showed higher NYHA and pVO2 regardless of drug dose, whereas, in not β-blocked patients, only %HRR revealed a difference in functional capacity. At multivariable analysis, HR increase during exercise (ΔHR) was the variable most strongly associated to pVO2 (β: 0.572; SE: 0.008; P < 0.0001) and NYHA class (β: −0.499; SE: 0.001; P < 0.0001). Conclusions: ΔHR is a powerful predictor of CHF severity regardless of the presence of β-blocker therapy and of β-blocker daily dose
Pro-oxidant and pro-inflammatory effects of glycated albumin on cardiomyocytes.
Human serum albumin (HSA) is the most abundant circulating protein in the body and presents an extensive range of biological functions. As such, it is prone to undergo post-translational modifications (PTMs). The non-enzymatic early glycation of HSA, one of the several PTMs undergone by HSA, arises from the addition of reducing sugars to amine group residues, thus modifying the structure of HSA. These changes may affect HSA functions impairing its biological activity, finally leading to cell damage. The aim of this study was to quantitate glycated-HSA (GA) levels in the plasma of heart failure (HF) patients and to evaluate the biological effects of GA on HL-1 cardiomyocytes. Plasma GA content from HF patients and healthy subjects was measured by direct infusion electrospray ionization mass spectrometry (ESI-MS). Results pointed out a significant increase of GA in HF patients with respect to the control group (p < 0.05). Additionally, after stimulation with GA, proteomic analysis of HL-1 secreted proteins showed the modulation of several proteins involved, among other processes, in the response to stress. Further, stimulated cells showed a rapid increase in ROS generation, higher mRNA levels of the inflammatory cytokine interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α), and higher levels of the oxidative 4-HNE-protein adducts and carbonylated proteins. Our findings show that plasma GA is increased in HF patients. Further, GA exerts pro-inflammatory and pro-oxidant effects on cardiomyocytes, which suggest a causal role in the etiopathogenesis of HF
Levosimendan Efficacy and Safety: 20 Years of SIMDAX in Clinical Use
Levosimendan was first approved for clinical use in 2000, when authorization was granted by Swedish regulatory authorities for the hemodynamic stabilization of patients with acutely decompensated chronic heart failure (HF). In the ensuing 20 years, this distinctive inodilator, which enhances cardiac contractility through calcium sensitization and promotes vasodilatation through the opening of adenosine triphosphate-dependent potassium channels on vascular smooth muscle cells, has been approved in more than 60 jurisdictions, including most of the countries of the European Union and Latin America. Areas of clinical application have expanded considerably and now include cardiogenic shock, takotsubo cardiomyopathy, advanced HF, right ventricular failure, pulmonary hypertension, cardiac surgery, critical care, and emergency medicine. Levosimendan is currently in active clinical evaluation in the United States. Levosimendan in IV formulation is being used as a research tool in the exploration of a wide range of cardiac and noncardiac disease states. A levosimendan oral form is at present under evaluation in the management of amyotrophic lateral sclerosis. To mark the 20 years since the advent of levosimendan in clinical use, 51 experts from 23 European countries (Austria, Belgium, Croatia, Cyprus, Czech Republic, Estonia, Finland, France, Germany, Greece, Hungary, Italy, the Netherlands, Norway, Poland, Portugal, Russia, Slovenia, Spain, Sweden, Switzerland, the United Kingdom, and Ukraine) contributed to this essay, which evaluates one of the relatively few drugs to have been successfully introduced into the acute HF arena in recent times and charts a possible development trajectory for the next 20 years
Right ventricular failure in left heart disease: from pathophysiology to clinical manifestations and prognosis
Right heart failure (RHF) is a clinical syndrome in which symptoms and signs are caused by dysfunction and/or overload of the right heart structures, predominantly the right ventricle (RV), resulting in systemic venous hypertension, peripheral oedema and finally, the impaired ability of the right heart to provide tissue perfusion. Pathogenesis of RHF includes the incompetence of the right heart to maintain systemic venous pressure sufficiently low to guarantee an optimal venous return and to preserve renal function. Virtually, all myocardial diseases involving the left heart may be responsible for RHF. This may result from coronary artery disease, hypertension, valvular heart disease, cardiomyopathies and myocarditis. The most prominent clinical signs of RHF comprise swelling of the neck veins with an elevation of jugular venous pressure and ankle oedema. As the situation worsens, fluid accumulation becomes generalised with extensive oedema of the legs, congestive hepatomegaly and eventually ascites. Diagnosis of RHF requires the presence of signs of elevated right atrial and venous pressures, including dilation of neck veins, with at least one of the following criteria: (1) compromised RV function; (2) pulmonary hypertension; (3) peripheral oedema and congestive hepatomegaly. Early recognition of RHF and identifying the underlying aetiology as well as triggering factors are crucial to treating patients and possibly reversing the clinical manifestations effectively and improving prognosis
Brisk walking can be a maximal effort in heart failure patients: a comparison of cardiopulmonary exercise and 6Â min walking test cardiorespiratory data
Aims Cardiopulmonary exercise test (CPET) and 6 min walking test (6MWT) are frequently used in heart failure (HF). CPET is a maximal exercise, whereas 6MWT is a self-selected constant load test usually considered a submaximal, and therefore safer, exercise, but this has not been tested previously. The aim of this study was to compare the cardiorespiratory parameters collected during CPET and 6MWT in a large group of healthy subjects and patients with HF of different severity.Methods and results Subjects performed a standard maximal CPET and a 6MWT wearing a portable device allowing breath-by-breath measurement of cardiorespiratory parameters. HF patients were grouped according to their CPET peak oxygen uptake (peak(V) over-dotO(2)). One hundred and fifty-five subjects were enrolled, of whom 40 were healthy (59 +/- 8 years; male 67%) and 115 were HF patients (69 +/- 10 years; male 80%; left ventricular ejection fraction 34.6 +/- 12.0%). CPET peak(V) over-dotO(2) was 13.5 +/- 3.5 ml/kg/min in HF patients and 28.1 +/- 7.4 mL/kg/min in healthy subjects (P < 0.001). 6MWT-(V) over-dotO(2) was 98 +/- 20% of the CPET peak(V) over-dotO(2) values in HF patients, while 72 +/- 20% in healthy subjects (P < 0.001). 6MWT-(V) over-dot was >110% of CPET peak(V) over-dotO(2) in 42% of more severe HF patients (peak(V) over-dotO(2) < 12 mL/kg/min). Similar results have been found for ventilation and heart rate. Of note, the slope of the relationship between (V) over-dotO(2) at 6MWT, reported as a percentage of CPET peak(V) over-dotO(2) vs. 6MWT (V) over-dotO(2) reported as the absolute value, progressively increased as exercise limitation did.Conclusions In conclusion, the last minute of 6MWT must be perceived as a maximal or even supramaximal exercise activity in patients with more severe HF. Our findings should influence the safety procedures needed for the 6MWT in HF
Reference Values for Peak Exercise Cardiac Output in Healthy Individuals
BACKGROUND:
Cardiac output (Q\u2d9) is a key parameter in the assessment of cardiac function, its measurement being crucial for the diagnosis, treatment, and prognostic evaluation of all heart diseases. Until recently, Q\u2d9 determination at peak exercise has been possible through invasive methods, so that normal values were obtained in studies based on small populations.
METHODS:
Nowadays, peak Q\u2d9 can be measured noninvasively by means of the inert gas rebreathing (IGR) technique. The present study was undertaken to provide reference values for peak Q\u2d9 in the normal general population and to obtain a formula able to estimate peak exercise Q\u2d9 from measured peak oxygen uptake (V\u2d9o2).
RESULTS:
We studied 500 normal subjects (age, 44.9 \ub1 1.5 years; range, 18-77 years; 260 men, 240 women) who underwent a maximal cardiopulmonary exercise test with peak Q\u2d9 measurement by IGR. In the overall study sample, peak Q\u2d9 was 13.2 \ub1 3.5 L/min (men, 15.3 \ub1 3.3 L/min; women, 11.0 \ub1 2.0 L/min; P < .001) and peak V\u2d9o2 was 95% \ub1 18% of the maximum predicted value (men, 95% \ub1 19%; women, 95% \ub1 18%). Peak V\u2d9o2 and peak Q\u2d9 progressively decreased with age (R2, 0.082; P < .001; and R2, 0.144; P < .001, respectively). The V\u2d9o2-derived formula to measure Q\u2d9 at peak exercise was (4.4
7 peak V\u2d9o2) + 4.3 in the overall study cohort, (4.3
7 peak V\u2d9o2) + 4.5 in men, and (4.9
7 peak V\u2d9o2) + 3.6 in women.
CONCLUSIONS:
The simultaneous measurement of Q\u2d9 and V\u2d9o2 at peak exercise in a large sample of healthy subjects provided an equation to predict peak Q\u2d9 from peak V\u2d9o2 values
Comparison of the diagnostic performance of 64-slice computed tomography coronary angiography in diabetic and non-diabetic patients with suspected coronary artery disease
<p>Abstract</p> <p>Background</p> <p>Diabetics have high prevalence of subclinical coronary artery disease (CAD) with typical characteristics (diffuse disease, large calcifications). Although 64-slice multidetector computed tomography (MDCT) coronary angiography has high diagnostic accuracy to detect CAD, its diagnostic performance in diabetics with suspected CAD is unknown. To compare the diagnostic performance of 64-slice MDCT between diabetics and non-diabetics with suspected CAD scheduled for invasive coronary angiography (ICA).</p> <p>Methods</p> <p>We enrolled one hundred and five diabetic patients (92 men, age 65 +/- 9 years, Group 1) and 105 non-diabetic patients (63 men, age 63+/-5 years, Group 2) with indication to ICA for suspected CAD undergoing coronary 64-slice MDCT before ICA.</p> <p>Results</p> <p>In Group 1, the overall feasibility of coronary artery visualization was 93.8%. The most frequent artifact was blooming due to large coronary calcifications (54 artifacts, 67%). In Group 2, the overall feasibility was significantly higher vs. Group 1 (97%, p < 0.0001). In Group 1, the segment-based analysis showed a MDCT sensibility, specificity, positive predictive value, negative predictive value and accuracy for the detection of ≥50% luminal narrowing of 77%, 90%, 70%, 93% and 87%, respectively. In Group 2, all these parameters were significantly higher vs. Group 1. In the patient-based analysis, specificity, negative predictive value and accuracy were significantly lower in Group 1 vs. Group 2.</p> <p>Conclusions</p> <p>Although MDCT has high sensitivity for early identification of significant CAD in diabetics, its diagnostic performance is significantly reduced in these patients as compared to non-diabetics with similar clinical characteristics.</p
Exercise performance, haemodynamics, and respiratory pattern do not identify heart failure patients who end exercise with dyspnoea from those with fatigue
AIMS:
The two main symptoms referred by chronic heart failure (HF) patients as the causes of exercise termination during maximal cardiopulmonary exercise testing (CPET) are muscular fatigue and dyspnoea. So far, a physiological explanation why some HF patients end exercise because of dyspnoea and others because of fatigue is not available. We assessed whether patients referring dyspnoea or muscular fatigue may be distinguished by different ventilator or haemodynamic behaviours during exercise.
METHODS AND RESULTS:
We analysed exercise data of 170 consecutive HF patients with reduced left ventricular ejection fraction in stable clinical condition. All patients underwent maximal CPET and a second maximal CPET with measurement of cardiac output by inert gas rebreathing at peak exercise. Thirty-eight (age 65.0 \ub1 11.1 years) and 132 (65.1 \ub1 11.4 years) patients terminated CPET because of dyspnoea and fatigue, respectively. Haemodynamic and cardiorespiratory parameters were the same in fatigue and dyspnoea patients. VO2 was 10.4 \ub1 3.2 and 10.5 \ub1 3.3 mL/min/kg at the anaerobic threshold and 15.5 \ub1 4.8 and 15.4 \ub1 4.3 at peak, in fatigue and dyspnoea patients, respectively. In fatigue and dyspnoea patients, peak heart rate was 110 \ub1 22 and 114 \ub1 22 beats/min, and VE/VCO2 and VO2 /work relationship slopes were 31.2 \ub1 6.8 and 30.6 \ub1 8.2 and 10.6 \ub1 4.2 and 11.4 \ub1 5.5 L/min/W, respectively. Peak cardiac output was 6.68 \ub1 2.51 and 6.21 \ub1 2.55 L/min (P = NS for all).
CONCLUSIONS:
In chronic HF patients in stable clinical condition, fatigue and dyspnoea as reasons of exercise termination do not highlight different ventilatory or haemodynamic patterns during effort
Interleukin-1β levels predict long-term mortality and need for heart transplantation in ambulatory patients affected by idiopathic dilated cardiomyopathy
The prognostic stratification of patients with Idiopathic Dilated Cardiomyopathy (iDCM) is a difficult task. Here, we assessed the additive value of the evaluation of biomarkers of inflammasome activation and systemic inflammation for the long-term risk stratification of iDCM patients
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