Chronic congestive heart failure

A complex clinical syndrome that can result from any structural or functional cardiac disorder that impairs the ability of the ventricle to fill with or eject blood.

It is a major and growing public health problem. It is the only cardiovascular disease that is increasing in incidence and prevalence, partly because the population is ageing, but also because of improved cardiovascular interventions for disease processes that reduce early mortality but may result in cardiac changes that lead to heart failure.

The key manifestations are dyspnoea and fatigue, which may limit exercise tolerance, and fluid retention, which may lead to pulmonary congestion and peripheral oedema.

Diagnosis is largely clinical; a thorough history and physical examination should be obtained to identify cardiac and non-cardiac disorders or behaviours that might cause CHF or accelerate progression.

The single most useful diagnostic test in the evaluation of patients is the comprehensive 2-dimensional echocardiogram coupled with Doppler flow studies. Measurement of B-type natriuretic peptide (BNP) can be useful in the evaluation of patients at initial presentation.

Interventions that have a proven beneficial impact on patient survival include ACE inhibitors, angiotensin receptor blockers, beta-blockers, aldosterone antagonists, hydralazine and nitrates, cardiac re-synchronisation therapy, and implantable cardioverter defibrillators.

Heart failure is a condition in which the heart is unable to generate a cardiac output sufficient to meet the demands of the body without increasing diastolic pressure. It can result from any cardiac disease that compromises ventricular systolic or diastolic function or both. The term 'congestive heart failure' is reserved for patients with breathlessness and abnormal sodium and water retention resulting in oedema.

Heart failure comprises a wide range of clinical scenarios, from patients with normal left ventricular ejection fraction (LVEF) >50% to those with reduced myocardial contractility (LVEF<40%).

Based on LVEF, heart failure is defined as follows. [1] Ponikowski P, Voors AA, Anker SD, et al. 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure: the task force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). Eur J Heart Fail. 2016;18:891-975. http://onlinelibrary.wiley.com/doi/10.1002/ejhf.592/full http://www.ncbi.nlm.nih.gov/pubmed/27207191?tool=bestpractice.com

1. Heart failure with reduced ejection fraction (HFrEF): symptoms and signs with LVEF <40%.

2. Heart failure with mid-range ejection fraction (HFmrEF): symptoms and signs with LVEF 40% to 49%. Other features include elevated natriuretic peptides (B-type natriuretic peptide [BNP] >35 nanograms/L [>35 picograms/mL] or N-terminal pro-brain natriuretic peptide [NT-pro-BNP] >125 nanograms/L [>125 picograms/mL]) and at least one additional criterion: (a) relevant structural heart disease (e.g., left ventricular hypertrophy [LVH] or left atrial enlargement), (b) diastolic dysfunction.

3. Heart failure with preserved ejection fraction (HFpEF): symptoms and signs with LVEF >50%. Other features include elevated natriuretic peptides (BNP >35 nanograms/L [>35 picograms/mL] or NT-pro-BNP >125 nanograms/L [>125 picograms/mL]) and at least one additional criteria: (a) relevant structural heart disease (e.g., LVH or left atrial enlargement), (b) diastolic dysfunction.