Right Heart in Dilated Cardiomyopathy
Dilated cardiomyopathy (DCM) is a significant burden affecting 5 people in 100,000, it is also the most common cardiomyopathy encountered. The condition can be a result of underlying diseases, which can comprimise the heart's contractility such as any insult to the heart, for example several viral or bacterial infections can lead to myocarditis, whereas other agents such as alcohol or illicit drug use can exert direct cardiotoxic effects destabilizing the normal cardiac function. In many cases, however, no causing effect can be identified and thus, the condition is referred to as, idiopathic non ischemic (dilated) cardiomyopathy. This chapter is dedicated to understand the etiology, pathogenesis, clinical manifestation, diagnosis and treatment of DCM. Although left ventricular dysfunction is seen as the primary outcome of the disease, the right heart function and dysfunction does plays an important role. Physical examination, a complete history and assessment of current symtoms as well as an electrocardiogram, laboratory testing including metabolic panel, brain natriuretic peptide levels and echocardiogram are mainly utilized in the initial diagnostic work-up if cardiomyopathy as a reason for heart failure symptoms is suspected. Due to subtle symptoms of the disease patients oftentimes do not seek medical advice early in the course of the disease but only after severe and debilitating heart failure symptoms occur. Modern therapy is tailored to 1) alleviate symptoms, 2) improve outcomes and reduce mortality and morbidity, and 3) remove or ease the underlying causes in cases of secondary DCM. Whereas vasodilators such as nitrates and diuretics are often the first-line therapy to ease symptoms of shortness of breath and volume overload, early treatment with Angiotensin Converting Enzyme Inhibitors (ACEI) and Angiotensin Receptor Blockers (ARB) is initiated in order to used to prevent cardiac remodeling. Beta blockers have shown promising results to potentially reverse ventricular dilatation and further prevention of structural changes.
KeywordsCardiomyopathyHeart failure Cardiac remodeling
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