Acute heart failure: Emerging from the shadows

Abstract

As we emerge from the tremendous progress of the last century, we can take genuine pride in the advances of modern treatments in reducing the morbidity and mortality of cardiovascular diseases, such as hypertension, myocardial infarction, and chronic heart failure. Unfortunately, acute heart failure (AHF) remained largely ignored during this period of discovery, with little research into its epidemiology, pathophysiology, diagnosis, or treatment. However, recent recognition of the significance of AHF has led to investigations that have provided important insights into this syndrome (1), guidelines for its treatment and diagnosis (2, 3), and novel therapies (4), as well as new chapters in leading cardiology textbooks (5). This supplement to Critical Care Medicine is intended to report on the current state of the art as presented by leaders in this rapidly evolving field. Acute heart failure can be defined as the rapid or gradual onset of signs and symptoms of heart failure that result in an urgent, unplanned need for medical care. This heterogeneous syndrome is the primary diagnosis in 1 million hospitalizations in the United States alone, constituting a 174% increase from 1979 to 2003. Drawing on contemporary studies and providing the context for further discourse, Drs. Dar and Cowie (6) present a survey of the epidemiology of AHF, revealing that AHF patients are typically elderly with a history of heart failure, coronary artery disease, and multiple other comorbidities. Our understanding of the pathogenesis of AHF has relied heavily on our models of chronic heart failure, which initially focused on hemodynamic derangements. It is becoming clear, however, that other important mechanisms may be operative in the development of AHF, such as cytokine activation, as described by Dr. Chen and colleagues (7). The potential role of inflammation and immune activation in myocardial dysfunction and damage in the setting of AHF not only may explain the increased morbidity and mortality observed in these patients but also may provide a rationale for future therapeutic targets. The diagnosis of AHF has dramatically improved in the last decade with the advent of new diagnostic modalities. Perhaps the most significant of these tests have been the assays for natriuretic peptides, B-type natriuretic peptide (BNP), and its precursor (NT-proBNP). Dr. Omland (8) discusses these new assays and their practical use in the clinical environment as well as their contributions to estimating clinical course and prognosis. Cardiac imaging technologies have also rapidly improved, and echocardiography is an essential tool in the diagnosis and management of patients with AHF. Dr. Ferrari (9) discusses the role of echocardiography and the exciting new techniques of cardiac computed tomography and magnetic resonance imaging in the management of patients with heart failure. Recent trials have provided new perspectives on the use of hemodynamic monitoring in patients with AHF. Dr. Cotter and associates (10) present the current data regarding invasive hemodynamic monitoring, provide guidance for the use of this important tool, and discuss new noninvasive measurement techniques. As noted previously, AHF is a heterogeneous syndrome, and defining the sub