Routine serial echocardiography in systolic heart failure: is it time for the heart failure guidelines to change?

The authors sought to obtain objective evidence for impacting the American College of Cardiology Heart Failure Guidelines for the routine use of serial echocardiography by assessing the reliability of the use of clinician-assessed patient symptoms and New York Heart Association (NYHA) functional classification compared with ejection fraction (EF) measured by echocardiography. A prospective study in 256 patients with systolic heart failure (HF) enrolled into an HF disease management program with EF ≤40% and at least 2 annual echocardiograms were included. Only 86 of 256 (33.5%) patients were correctly classified by NYHA class as showing improvement, no change, or deterioration as compared with echocardiographic assessments. Patients whose NYHA class showed no change between echocardiograms had the lowest survival rate. Quantification in patient's status with NYHA classification is not always a reliable assessment to evaluate prognosis and guide medical therapy for patients with systolic HF.     

Atrial fibrillation in heart failure: the chicken or the egg?

Atrial fibrillation (AF) and heart failure (HF) are the emerging epidemics of cardiovascular disease in the new millennium. Both are responsible for considerable morbidity and mortality and health budget expenditure. The advent of catheter ablation for patients with AF has provided important new insights into the relative contribution of AF to left ventricular dysfunction. The aim of this review is to discuss the complex interplay in the pathophysiology of AF and HF to improve our understanding of the basis for current treatment strategies and guide future research direction.     

Does rhythm matter? The prognostic importance of atrial fibrillation in heart failure

BACKGROUND: Atrial fibrillation (AF) and congestive heart failure (HF) often coexist, but there is conflicting data regarding the association of AF with outcome in HF. To examine this further we have evaluated the prognostic effect of AF in two complementary CHF populations; a population based data set of 55,106 patients admitted to hospital with CHF, and a cohort of 197 patients recruited after a hospital admission with HF into a management clinical trial. METHODS: Firstly, data for all hospital admissions in New Zealand from 1988 to 1997 were obtained. Using coding data, 55,106 first admissions for HF were identified, the presence of AF was determined by secondary diagnosis coding, and all cause mortality was obtained. Secondly, patients enrolled in the Auckland Heart Failure Management Study were evaluated for the presence or absence of AF, and for all cause mortality at three years. RESULTS: Mortality at 30 days, 6 and 12 months was significantly lower for AF patients compared to sinus rhythm (SR) in the national admissions cohort. In the clinical trial cohort the presence of AF was also associated with lower three-year mortality, although this difference was not seen when the groups were stratified by Doppler mitral filling pattern (a restrictive filling pattern was associated with reduced longevity compared to SR, non-restrictive or AF). CONCLUSIONS: This data shows that the presence of AF in two general HF populations in New Zealand is not associated with an adverse prognosis. HF severity, and in particular a restrictive filling pattern, remain powerful predictors of mortality.     

Increasing atrial fibrillation: What is the cause?

A 72‐year‐old woman with a history of paroxysmal atrial fibrillation (AF) and sinus node dysfunction is seen in clinic for routine follow‐up.     

What determines the heart rate response to exercise in patients with atrial fibrillation?

We evaluated the factors that determine the heart rate response to exercise in 60 patients with atrial fibrillation (25 men and 35 women, with a mean age of 61+/-10 years) who underwent symptom limited cardiopulmonary exercise testing with blood sampling of atrial natriuretic peptide (ANP), 2-dimensional echocardiography and cardiac catheterization. Atrial muscles resected during the Maze operation were examined histologically in 12 patients. The heart rate response to exercise depended on the severity of the atrial organic injury, which was expressed as left atrial diameter, ANP secretion during the maximal exercise testing and the histological findings of atrial tissue. Conversely, we believe that the severity of the atrial injury can be predicted from the heart rate response to exercise in patients with atrial fibrillation.     

Is rhythm control superior to rate control in patients with atrial fibrillation and congestive heart failure?

In 1,009 patients with atrial fibrillation and congestive heart failure, the 2-year mortality rate was 31% in patients treated with rate control (n = 505) versus 29% in patients treated with rhythm control (n = 504). After adjusting for differences in baseline characteristics and medications, no significant difference in mortality was found between the 2 groups.     

Carvedilol alone or in combination with digoxin for the management of atrial fibrillation in patients with heart failure?

OBJECTIVES: This study examined the relative merits of digoxin, carvedilol, and their combination for the management of patients with atrial fibrillation (AF) and heart failure (HF). BACKGROUND: In patients with AF and HF, both digoxin and beta-blockers reduce the ventricular rate, and both may improve symptoms, but only beta-blockers have been shown to improve prognosis. If combined therapy is not superior to beta-blockers alone, treatment of patients with HF and AF could be simplified by stopping digoxin. METHODS: We enrolled 47 patients (29 males; mean age 68 years) with persistent AF and HF (mean left ventricular ejection fraction [LVEF] 24%) in a randomized, double-blinded, placebo-controlled study. In the first phase of the study, digoxin was compared with the combination of digoxin and carvedilol (four months). In the second phase, digoxin was withdrawn in a double-blinded manner in the carvedilol-treated arm, thus allowing a comparison between digoxin and carvedilol (six months). Investigations were undertaken at baseline and at the end of each phase. RESULTS: Compared with digoxin alone, combination therapy lowered the ventricular rate on 24-h ambulatory electrocardiographic monitoring (p < 0.0001) and during submaximal exercise (p < 0.05), whereas LVEF (p < 0.05) and symptom score (p < 0.05) improved. In phase 2, there was no significant difference between digoxin alone and carvedilol alone in any variable. The mean ventricular rate rose and LVEF fell when patients switched from combination therapy to carvedilol alone. Six-minute walk distance was not significantly influenced by any therapy. CONCLUSIONS: The combination of carvedilol and digoxin appears generally superior to either carvedilol or digoxin alone in the management of AF in patients with HF.