**2.4 Pathophysiological aspects and etiology**

As a consequence of the definition, the etiology of left ventricular dilatation and dysfunction is heterogeneous. In developed countries, CAD is the most common cause of left ventricular dilatation and dysfunction, and responsible for approximately 50–70% of HF patients. Therefore, potentially reversible myocardial ischemia must always be excluded for the diagnosis of DCM. The following section describes in detail the possible causes of the DCM (**Figure 1**). However, the current literature underscores that the cause of DCM remains unknown, that is, IDC, in half of the patients [23].
