Heart failure burden and therapy

Heart failure (HF) is a syndrome with a broad spectrum of heterogeneous symptoms and signs resulting in a wide range of clinical expressions. The prevalence of HF is estimated to be 1-2% in developed countries, increasing with age. Heart failure is the leading cause of hospitalization for patients older than 65 years, raising concerns about the economic burden of this syndrome. This article provides a critical review of epidemiological and clinical aspects for HF; causes, comorbidities, and types of HF are also described. The systolic vs. diastolic, the acute vs. chronic approaches, and the connections between HF and left bundle branch block or atrial fibrillation are further detailed. In addition, a synthesis of the latest results and recommendations concerning the indication and the prescription of pharmacological (such as diuretics or rennin-angiotensin-aldosterone system inhibitors) and non-pharmacological treatments (particularly device therapy) is proposed.

Endogenous B-type natriuretic peptide: a limb of the regulatory response to acutely decompensated heart failure

Acutely decompensated heart failure (ADHF) represents an episodic failure of cardiorenal homeostasis that may resolve with upregulation of natriuretic peptides, bradykinin, and certain prostacyclins. B-type natriuretic peptide (BNP) has multiple favorable effects, including vasodilation, diuresis, natriuresis, and inhibition of vascular endothelial proliferation and cardiac fibrosis. By antagonizing the effects of activation of the renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system in volume overload, the endogenous BNP response may help rescue patients from episodic ADHF. Although knowledge of BNP physiology is expanding, we still have limited understanding of the heterogeneity of proBNP-derived molecules, including active 32 amino acid BNP and less active junk BNP forms. Emerging evidence suggests that in ADHF, the endogenous BNP response is overwhelmed by neurohormonal activation. This relative BNP deficiency may also be accompanied by physiologic resistance to BNP. Additionally, abnormalities of BNP production may result in a lower proportion of active BNP relative to less active forms that may also be detected by point-of-care tests. Improved detection of the various BNP species may clarify these concepts and facilitate improved clinical management of ADHF.

Ejection fraction and blood pressure are important and interactive predictors of 4-week mortality in severe acute heart failure

BACKGROUND

In acute heart failure syndromes (AHFS), the prognostic value of left ventricular ejection fraction (LVEF), although widely accepted, has been recently challenged. In contrast, blood pressure is increasingly gaining ground over LVEF as predictor of mortality. Therefore, it is not clear whether both LVEF and mean arterial pressure (MAP) are independent risk factors in patients with AHFS.

METHODS AND RESULTS

The EFICA study enrolled 581 AHFS patients admitted to 60 CCU/ICUs. Survival at 4 weeks was analyzed for all cases with echocardiographic LVEF available on admission (n=355). Four-week mortality was 23%. Multivariable analysis identified lower LVEF, lower MAP and serum creatinine >1.5 mg/dl as independent correlates of mortality (respectively, OR: 1.27 per 10% decrease, CI: 1.05-1.53, p=0.012; OR: 1.30 per 10 mmHg decrease, CI: 1.15-1.48, p<0.0001; OR: 2.84, CI: 1.64-4.93, p=0.0002). LVEF interacted significantly with MAP (p<0.0001) and the subgroup analysis showed that reduced LVEF was a strong risk factor in patients with MAP <or=90 mmHg (OR: 2.73, CI: 1.23-5.98, p=0.01) but did not reach statistical significance in patients with MAP >90 mmHg.

CONCLUSIONS

Both LVEF and MAP are important predictors of death in severe AHFS. LVEF can provide additional prognostic information on top of MAP but mainly in patients with low MAP (<or=90 mmHg) at admission.

Epidemiology of acute heart failure syndromes

Acute Heart Failure is a heterogeneous set of syndromes associated with significant morbidity and mortality. There are several classifications of acute heart failure syndromes (AHFS) based on pathophysiology or clinical presentation. In the USA and in Europe, AHFS are the first cause of hospitalization of the elderly, and the leading health care cost. Despite this clinical and social importance, AHFS have received little attention from clinicians and researchers. Recently published epidemiological studies described clinical presentation, characteristics and treatment of over 100,000 patients hospitalized with AHFS. These studies also underlined the poor, short, and medium term prognosis, especially for the most severe patients admitted to an intensive care unit, with in-hospital mortality of 28%. Further epidemiological and clinical research is needed to improve our understanding of AHFS, thereby enhancing patient care.

The challenge of acute decompensated heart failure

Acute heart failure syndromes (AHFS) is a broad spectrum of heterogeneous conditions including pulmonary oedema, hypertensive crisis, worsening exacerbated CHF and cardiogenic shock. HF hospitalizations have steadily risen with more than one million in 2004 in the United States and a similar number has been reported in Europe. Each year heart failure accounts for 6.5 million days spent in hospital in the USA and 1.4 million days in France. Mortality data are derived from registries or clinical trials. Registry data in patients admitted to general or cardiology wards such as in Euroheart Failure Survey and ADHERE provide a far more optimistic picture compared with data from consecutive unselected patients in the most acute situation. such as in EFICA. Four-week mortality was higher than 25% in this case. A great pathophysiologic understanding of the different features of the various AHFS is needed in order to identify targets for therapy and research. This includes hemodynamics, the role of myocardial injury, neurohormonal and cytokine abnormalities and the cardiorenal syndromes. So far, very little progress has been made in developing new, effective therapies and implementing management guidelines in this patient population. Future clinical trial endpoints should be better designed and tailored to the various pathophysiological conditions of this complex syndrome. The goal of AHFS therapy is not only to prevent disease progression but also to have a beneficial effect on an acute event that exacerbates disease progression. A combined endpoint assessing survival and rehospitalisation rates is becoming increasingly popular for acute therapies. Specific trials may also need to be designed according to the time of access to the patient.