Livio Dei Cas

Effects of short- and long-term carvedilol administration on rest and exercise hemodynamic variables, exercise capacity and clinical conditions in patients with idiopathic dilated cardiomyopathy

OBJECTIVES The study evaluated the effects of short- and long-term administration of carvedilol in patients with idiopathic dilated cardiomyopathy. BACKGROUND Carvedilol is a beta-adrenergic blocking agent with vasodilator activity that might be well tolerated in patients with heart failure. METHODS Forty patients with idiopathic dilated cardiomyopathy treated with digoxin, furosemide and angiotensin-converting enzyme inhibitors were randomized in a double-blind manner to receive either placebo or carvedilol. Right heart hemodynamic variables were evaluated up to 8 h after short-term drug administration and, on the next day, during cardiopulmonary exercise testing before and 3 h after drug ingestion. Placebo or carvedilol was added to standard therapy, starting with a dose of 6.25 mg twice a day with weekly increments up to the maximum of 25 mg twice a day. Patients were reevaluated after 4 months by cardiopulmonary exercise testing and measurement of right heart hemodynamic variables 12 h after last drug ingestion and 3 h after drug readministration. Left ventricular ejection fraction and volume, measured by equilibrium radionuclide ventriculography, quality of life and submaximal exercise duration were assessed before and after long-term therapy. RESULTS Compared with placebo, carvedilol produced a short-term reduction in heart rate and pulmonary artery and pulmonary wedge pressures and, after long-term administration, increased both rest and peak exercise cardiac, stroke volume and stroke work indexes, with a further reduction in right atrial, pulmonary artery and pulmonary wedge pressures. Long-term carvedilol administration also improved rest left ventricular ejection fraction (from 20 +/- 7% to 30 +/- 12%, p < 0.001), submaximal exercise capacity, quality of life and New York Heart Association functional class. No baseline variable was predictive of the response to therapy. CONCLUSIONS Short-term carvedilol administration reduces heart rate and mean pulmonary artery and pulmonary wedge pressures, whereas it improves both long-term rest and exercise left ventricular systolic function, reduces heart failure symptoms and improves submaximal exercise tolerance in patients with idiopathic cardiomyopathy.

Differential Effects of β-Blockers in Patients With Heart Failure: A Prospective, Randomized, Double-Blind Comparison of the Long-Term Effects of Metoprolol Versus Carvedilol

BACKGROUND Both metoprolol and carvedilol produce hemodynamic and clinical benefits in patients with chronic heart failure; carvedilol exerts greater antiadrenergic effects than metoprolol, but it is unknown whether this pharmacological difference results in hemodynamic and clinical differences between the 2 drugs. METHODS AND RESULTS We randomized 150 patients with heart failure (left ventricular ejection fraction </=0.35) to double-blind treatment with either metoprolol or carvedilol. When compared with metoprolol (124+/-55 mg/d), patients treated with carvedilol (49+/-18 mg/d) showed larger increases in left ventricular ejection fraction at rest (+10.9+/-11.0 versus +7.2+/-7.7 U, P=0.038) and in left ventricular stroke volume and stroke work during exercise (both P<0. 05) after 13 to 15 months of treatment. In addition, carvedilol produced greater decreases in mean pulmonary artery pressure and pulmonary wedge pressure, both at rest and during exercise, than metoprolol (all P<0.05). In contrast, the metoprolol group showed greater increases in maximal exercise capacity than the carvedilol group (P=0.035), but the 2 drugs improved symptoms, submaximal exercise tolerance, and quality of life to a similar degree. After a mean of 23+/-11 months of follow-up, 21 patients in the metoprolol group and 17 patients in the carvedilol group died or underwent urgent transplantation. CONCLUSIONS The present study demonstrates that during long-term therapy, carvedilol improves cardiac performance to a greater extent than metoprolol when administered to patients with heart failure in the doses shown to be effective in clinical trials. These differences were likely related to a greater antiadrenergic activity of carvedilol.

PTX3, A Prototypical Long Pentraxin, Is an Early Indicator of Acute Myocardial Infarction in Humans

BACKGROUND Inflammation is an important component of ischemic heart disease. PTX3 is a long pentraxin whose expression is induced by cytokines in endothelial cells, mononuclear phagocytes, and myocardium. The possibility that PTX3 is altered in patients with acute myocardial infarction (AMI) has not yet been tested. METHODS AND RESULTS Blood samples were collected from 37 patients admitted to the coronary care unit (CCU) with symptoms of AMI. PTX3 plasma concentrations, as measured by ELISA, higher than the mean+2 SD of age-matched controls (2.01 ng/mL) were found in 27 patients within the first 24 hours of CCU admission. PTX3 peaked at 7.5 hours after CCU admission, and mean peak concentration was 6.94+/-11.26 ng/mL. Plasma concentrations of PTX3 returned to normal in all but 3 patients at hospital discharge and were unrelated to AMI site or extent, Killip class at entry, hours from symptom onset, and thrombolysis. C-reactive protein peaked in plasma at 24 hours after CCU admission, much later than PTX3 (P<0.001). Patients >64 years old and women had significantly higher PTX3 concentrations at 24 hours (P<0.05). PTX3 was detected by immunohistochemistry in normal but not in necrotic myocytes. CONCLUSIONS PTX3 is present in the intact myocardium, increases in the blood of patients with AMI, and disappears from damaged myocytes. We suggest that PTX3 is an early indicator of myocyte irreversible injury in ischemic cardiomyopathy.

Worsening renal function in patients hospitalised for acute heart failure: Clinical implications and prognostic significance

Renal function is a powerful prognostic variable in patients with heart failure (HF). Hospitalisations for acute HF (AHF) may be associated with further worsening of renal function (WRF).

Differential Effects of β-Blockers in Patients With Heart Failure

Background—Both metoprolol and carvedilol produce hemodynamic and clinical benefits in patients with chronic heart failure; carvedilol exerts greater antiadrenergic effects than metoprolol, but it is unknown whether this pharmacological difference results in hemodynamic and clinical differences between the 2 drugs. Methods and Results—We randomized 150 patients with heart failure (left ventricular ejection fraction ≤0.35) to double-blind treatment with either metoprolol or carvedilol. When compared with metoprolol (124±55 mg/d), patients treated with carvedilol (49±18 mg/d) showed larger increases in left ventricular ejection fraction at rest (+10.9±11.0 versus +7.2±7.7 U, P=0.038) and in left ventricular stroke volume and stroke work during exercise (both P<0.05) after 13 to 15 months of treatment. In addition, carvedilol produced greater decreases in mean pulmonary artery pressure and pulmonary wedge pressure, both at rest and during exercise, than metoprolol (all P<0.05). In contrast, the metoprolol gr...

Beta-blocker therapy influences the hemodynamic response to inotropic agents in patients with heart failure: A randomized comparison of dobutamine and enoximone before and after chronic treatment with metoprolol or carvedilol

OBJECTIVE We compared the hemodynamic effects of dobutamine and enoximone administration before and after long-term beta-blocker therapy with metoprolol or carvedilol in patients with chronic heart failure (HF). BACKGROUND Patients with HF on beta-blocker therapy may need hemodynamic support with inotropic agents, and the hemodynamic response may be influenced by both the inotropic agent and the beta-blocker used. METHODS The hemodynamic effects of dobutamine (5 to 20 microg/kg/min intravenously) and enoximone (0.5 to 2 mg/kg intravenously) were assessed by pulmonary artery catheterization in 29 patients with chronic HF before and after 9 to 12 months of treatment with metoprolol or carvedilol at standard target maintenance oral doses. Hemodynamic studies were performed after >/=12 h of wash-out from all cardiovascular medications, except the beta-blockers that were administered 3 h before the second study. RESULTS Compared with before beta-blocker therapy, metoprolol treatment decreased the magnitude of mean pulmonary artery pressure (PAP) and pulmonary wedge pressure (PWP) decline during dobutamine infusion and increased the cardiac index (CI) and stroke volume index (SVI) response to enoximone administration, without any effect on other hemodynamic parameters. Carvedilol treatment abolished the increase in heart rate, SVI, and CI and caused a rise, rather than a decline, in PAP, PWP, systemic vascular resistance, and pulmonary vascular resistance during dobutamine infusion. The hemodynamic response to enoximone, however, was maintained or enhanced in the presence of carvedilol. CONCLUSIONS In contrast with its effects on enoximone, carvedilol and, to a lesser extent, metoprolol treatment may significantly inhibit the favorable hemodynamic response to dobutamine. No such beta-blocker-related attenuation of hemodynamic effects occurs with enoximone.

Is Worsening Renal Function an Ominous Prognostic Sign in Patients with Acute Heart Failure? The Role of Congestion and Its Interaction with Renal Function

Background— Worsening renal function (WRF), traditionally defined as an increase in serum creatinine levels ≥0.3 mg/dL, is a frequent finding in patients with acute heart failure (AHF) and has been associated with poorer outcomes in some but not all studies. We hypothesized that these discrepancies may be caused by the interaction between WRF and congestion in AHF patients. Methods and Results— We measured serum creatinine levels on a daily basis during the hospitalization and assessed the persistence of signs of congestion at discharge in 599 consecutive patients admitted at our institute for AHF. They had a postdischarge mortality and mortality or AHF readmission rates of 13% and 43%, respectively, after 1 year. Patients were subdivided into 4 groups according to the development or not of WRF and the persistence of ≥1 sign of congestion at discharge. Patients with WRF and no congestion had similar outcomes compared with those with no WRF and no congestion, whereas the risk of death or of death or AHF readmission was increased in the patients with persistent congestion alone and in those with both WRF and congestion (hazard ratio, 5.35; 95% confidence interval, 3.0–9.55 at univariable analysis; hazard ratio, 2.44; 95% confidence interval, 1.24–4.18 at multivariable analysis for mortality; hazard ratio, 2.14; 95% confidence interval, 1.39–3.3 at univariable analysis; and hazard ratio, 1.39; 95% confidence interval, 0.88–2.2 at multivariable analysis for mortality and rehospitalizations). Conclusions— WRF alone, when detected using serial serum creatinine measurements, is not an independent determinant of outcomes in patients with AHF. It has an additive prognostic value when it occurs in patients with persistent signs of congestion.Background— Worsening renal function (WRF), traditionally defined as an increase in serum creatinine levels ≥0.3 mg/dL, is a frequent finding in patients with acute heart failure (AHF) and has been associated with poorer outcomes in some but not all studies. We hypothesized that these discrepancies may be caused by the interaction between WRF and congestion in AHF patients. Methods and Results— We measured serum creatinine levels on a daily basis during the hospitalization and assessed the persistence of signs of congestion at discharge in 599 consecutive patients admitted at our institute for AHF. They had a postdischarge mortality and mortality or AHF readmission rates of 13% and 43%, respectively, after 1 year. Patients were subdivided into 4 groups according to the development or not of WRF and the persistence of ≥1 sign of congestion at discharge. Patients with WRF and no congestion had similar outcomes compared with those with no WRF and no congestion, whereas the risk of death or of death or AHF readmission was increased in the patients with persistent congestion alone and in those with both WRF and congestion (hazard ratio, 5.35; 95% confidence interval, 3.0–9.55 at univariable analysis; hazard ratio, 2.44; 95% confidence interval, 1.24–4.18 at multivariable analysis for mortality; hazard ratio, 2.14; 95% confidence interval, 1.39–3.3 at univariable analysis; and hazard ratio, 1.39; 95% confidence interval, 0.88–2.2 at multivariable analysis for mortality and rehospitalizations). Conclusions— WRF alone, when detected using serial serum creatinine measurements, is not an independent determinant of outcomes in patients with AHF. It has an additive prognostic value when it occurs in patients with persistent signs of congestion.

Exercise hyperventilation chronic congestive heart failure, and its relation to functional capacity and hemodynamics☆

The ventilatory response to exercise was evaluated in 26 normal sedentary men and 68 patients with chronic heart failure using the slope of the relation between minute ventilation (VE) and carbon dioxide production (VCO2). All subjects underwent maximal upright bicycle cardiopulmonary exercise testing; 33 patients also underwent right-sided cardiac catheterization. The slope of VE/VCO2 was calculated by linear regression analysis using data from all the exercise tests and the first 60% of exercise duration; a high correlation was seen between these results (r = 0.83; p less than 0.001). The slope of VE/VCO2 was significantly, though weakly, related to peak exercise work load, oxygen consumption and ventilatory threshold (r = -0.49, -0.56 and -0.49, respectively), several peak exercise hemodynamic parameters and peak exercise dead space/tidal volume ratio (r = 0.70). With use of multivariate analysis, the only independent determinants of the slope were peak exercise dead space/tidal volume ratio and cardiac index. Thus, in patients with heart failure, exercise hyperventilation can contribute to the impairment of functional capacity and can be considered a compensatory response to abnormal hemodynamics and lung blood distribution in order to keep blood gas concentrations normal.

The role of the kidney in heart failure

Renal dysfunction is common in patients with heart failure and is associated with high morbidity and mortality. Cardiac and renal dysfunction may worsen each other through multiple mechanisms such as fluid overload and increased venous pressure, hypo-perfusion, neurohormonal and inflammatory activation, and concomitant treatment. The interaction between cardiac and renal dysfunction may be critical for disease progression and prognosis. Renal dysfunction is conventionally defined by a reduced glomerular filtration rate, calculated from serum creatinine levels. This definition has limitations as serum creatinine is dependent on age, gender, muscle mass, volume status, and renal haemodynamics. Changes in serum creatinine related to treatment with diuretics or angiotensin-converting enzyme inhibitors are not necessarily associated with worse outcomes. New biomarkers might be of additional value to detect an early deterioration in renal function and to improve the prognostic assessment, but they need further validation. Thus, the evaluation of renal function in patients with heart failure is important as it may reflect their haemodynamic status and provide a better prognostic assessment. The prevention of renal dysfunction with new therapies might also improve outcomes although strong evidence is still lacking.

The role of plasma biomarkers in acute heart failure. Serial changes and independent prognostic value of NT‐proBNP and cardiac troponin‐T

Brain natriuretic peptide (BNP), NT‐proBNP and troponins are useful for the assessment of patients with heart failure. Few data exist about their serial changes and their prognostic value in patients with acute heart failure (AHF).