Is atrial function in Chagas dilated cardiomyopathy more impaired than in idiopathic dilated cardiomyopathy?

AIMS Atrial function is an important component in overall cardiovascular performance. However, information on atrial function in dilated cardiomyopathy is limited. This study aimed to assess atrial function in dilated cardiomyopathy and to investigate if parameters of atrial function are more impaired in Chagas dilated cardiomyopathy (CDC) than in idiopathic dilated cardiomyopathy (IDC). METHODS AND RESULTS Seventy-two patients with dilated cardiomyopathy (36 with CDC and 36 with IDC) and 32 healthy controls were evaluated by tissue Doppler, Doppler-based strain and strain rate (SR) imaging of the left atrium (LA) and right atrium (RA). Peak atrial strain during systole and SR during systole, early and late diastolic SR, were measured at the interatrial septum, LA inferior wall and at the lateral wall of the RA. The clinical characteristics and the parameters of LV function were similar between patients with CDC and IDC. Myocardial deformation indices during the reservoir phase of both RA and LA were lower in patients with dilated cardiomyopathy than in controls, suggesting atrial dysfunction in cardiomyopathies. However, LA and RA deformation parameters did not differ between CDC and IDC patients (interatrial septal strain during the reservoir phase: -25.2 ± 14.8 vs. -24.9 ± 16.0%, P = NS; strain rate during the reservoir phase: -1.3 ± 0.7 vs. -1.5 ± 0.9/s, P = NS). CONCLUSIONS Atrial myocardial deformation properties are abnormal in patients with dilated cardiomyopathy. CDC does not seem to have more atrial involvement than IDC.