[Segmental changes in contractility of the left heart ventricle in Chagas cardiomyopathy with and without ventricular dilatation].

PURPOSE: To evaluate left ventricular (LV) segmental wall motion abnormalities in dilated and nondilated chronic chagasic myocarditis (CCM), to better understand the myocardial dysfunction progression in this pathology.

METHODS

Sixty nine patients with the CCM, 39 had normal end-diastolic left ventricular dimension (LVEDD) and normal cardio-thoracic ratio (CTR) (group A), and 30 had increased LVEDD and CTR (group B), all of them with abnormal EKG, had the LV global and segmental contractility analysed by two-dimensional echocardiogram (Echo). A point score system to the LV contractility was applied.

RESULTS

Segmental wall motion abnormalities were seen in 68% of the patients: apical 64%, postero-inferior 30%, septal 17%, anterior 6% and lateral 0. Apical aneurysm was observed in 42% of the patients, postero-inferior in 6% and basal septal in 3%. There was a statistically significant correlation between the LVDD and the LV score of contractility (r = 0.66; p = 0.0000). The LV contractility was normal in 28% of the patients, 47% in group A and 3% in group B. While in group A the abnormal pattern of contractility was segmental in all, but one patient, in group B it was diffuse in the large majority (93%).

CONCLUSION

Initially LV abnormality in CCM is segmental. Beyond the apex, other regions of the LV are involved, the postero-inferior wall and basal septum for instance, even with aneurysm morphology. The CCM seems to evolve from an stage with essentially segmental wall motion abnormalities and normal LVDD to LV dilatation and diffuse hypocontractility.