Tissue Doppler imaging enables the identification of diastolic dysfunction of pseudonormal pattern in Chagas' disease

The Doppler pseudonormal pattern of left ventricular (LV) diastolic function filling, characterized by apparent normal transmitral flow velocities, indicates advanced diastolic dysfunction with abnormal relaxation and compliance. Left ventricular diastolic dysfunction has been shown to occur in the early stages of the outcome of Chagas cardiopathy, and its identification may potentially contribute to the management of those patients. The aim of this study was to evaluate the usefulness of tissue Doppler imaging (TDI) in identifying LV diastolic dysfunction in patients with Chagas' disease with pseudonormal transmitral flow. For this purpose, 89 patients with Chagas' disease (48 men) who had no other pathology and showed normal (n = 79) or pseudonormal (n = 10) patterns of diastolic function by pulsed wave Doppler were submitted to TDI. A significant LV systolic impairment in terms of the dimensions (P = .00001), ejection fraction (P = .000001), and wall motion score (P = .000002) was observed in patients with diastolic dysfunction when compared with the group with normal LV diastolic function. Tissue Doppler imaging enabled the recognition of a pseudonormal type of transmitral flow velocity with high statistical significance through early (P = .000008) and late (P = .0003) expansion waves. The sensitivity and specificity in detecting LV diastolic dysfunction with TDI in the septal, anterior, inferior, posterior, and lateral walls were 90% and 87.3%, 87.3% and 90%, 87.3% and 90%, 84.8% and 90%, and 84.8 and 90%, respectively. In conclusion, TDI enabled the differentiation of patients with Chagas' disease with normal LV diastolic function and those with the pathologic LV pseudonormal pattern with high statistical significance. Moreover, this article shows the potential in demonstrating the occurrence of major alterations in the LV performance of patients with Chagas' disease with LV diastolic dysfunction, as well as the occurrence of signs of an increased LV filling pressure in those patients.