Heart failure in dilated non-ischaemic cardiomyopathy

Heart failure (HF) is the prevailing cause of morbidity and mortality in patients with dilated non-ischaemic cardiomyopathy (DCM) and DCM is one of several causes of HF, with several distinct epidemiological and clinical features which may have important implications for its management and prognosis. This article reviews cardiovascular monitoring of specific characteristics of HF in DCM. DCM is defined as ventricular dilatation and systolic dysfunction in the absence of abnormal loading conditions or significant coronary artery disease, the predominant phenotypes of being HFmrEF or HFrEF. DCM accounts for ∼40% of all cardiomyopathies but its true prevalence among patients with HFrEF is difficult to ascertain with certainty. Compared with patients with other HF aetiologies, individuals with DCM tend to be younger, more likely male and less likely to have associated comorbidities. A genetic aetiology of DCM is deemed responsible for ∼40% of cases. Confirmation of a specific genetic background is clinically relevant (e.g. Duchene or Backer muscular dystrophies, lamin A/C mutation), because those patients may be at a high risk of progressive left ventricular dysfunction or conduction system disease and sudden death, prompting early prophylaxis with an implantable cardioverter defibrillator. However, in most instances, HF in DCM has a multifactorial aetiology, with multiple factors needing to be systematically evaluated and/or monitored, since correction of reversible causes or (e.g. tachycardia-induced cardiomyopathy, alcohol intoxication, iron-overload, cancer therapies etc.) or targeting specific pathophysiological causes could lead to an improvement in clinical status. The treatment of DCM encompasses HF-related pharmacological and device therapies, and aetiology-specific treatments. At present, options for aetiology-related therapies are limited, and their effectiveness mostly requires confirmation from larger scale randomized trials. Whether outcomes of patients with HF in DCM differ from those with other HF aetiologies is unresolved. DCM is attributable for >40% of patients receiving mechanical circulatory support for advanced HF and it is the leading indication for heart transplantation. More aetiology-specific information is needed both in the evaluation and treatment of dilated cardiomyopathy.