Objectives: To study ventricular asynchronism with tissue Doppler imaging in patients with primitive dilated cardiomyopathy and narrow QRS.
Patients and methods: We compared a group of patients with DCM and QRS < 120 ms (gr 1, n=25, 52+/-14 yrs, LVEF: 25+/-9%) with a group of normal patients (gr 2, n=16, 36+/-20 yrs). We measured the delays between the beginning of QRS and the beginnings of aortic (QA), mitral (QM), tricuspid (QT) and pulmonary (QP) flows, and of systolic (QSm) and protodiastolic (QEm) wall motion waves recorded with TDI in the basal portion of interventricular septum (IVS) and LV and RV free walls. We then calculated the differences QA-QP, QM-QT, the interparietal differences for QSm and QEm, and the maximal interparietal systolic (QSm max) and diastolic (QEm max) delays.
Results: QA, QP, QM and QT were significantly lengthened in group 1 patients but there were no difference between both groups for QA-QP and QM-QT. There was a trend toward a lengthening of QSm and QEm in group 1 patients. Interparietal differences of QSm and QEm were similar in both groups; however, QSm max and QEm max were significantly longer in group 1 patients than in group 2.
Conclusion: Doppler study of patients with DCM and narrow QRS shows a lengthening of all electromechanical delays and suggests some degree of ventricular asynchronism by showing a significant increase in maximal interparietal systolic and diastolic delays.