Assessment of left ventricular systolic and diastolic dyssynchrony with tissue Doppler echocardiography in patients with heart failure and narrow QRS complex.

AIM: Cardiac dyssynchrony is a well known entity in patients with wide QRS complex (>120 ms). Dyssynchrony may also cause ventricular dysfunction in heart failure patients with narrow QRS complexes. In the study, the presence and extent of cardiac dyssynchrony were investigated in patients with heart failure both with narrow and wide QRS complexes using tissue Doppler echocardiography (TDE). METHODS: Forty-nine patients with heart failure, were included to the study. The first group of 30 patients with a QRS duration of <120 ms (23M; mean age, 64±10.1 years) and the second group consisted of 19 patients with a QRS duration of >120 ms (12M; mean age, 65±11.6 years). In order to examine cardiac synchronization, TDE was performed. Systolic and diastolic intraventricular dyssynchrony and interventricular dyssynchrony were calculated. In order to define systolic and diastolic dyssynchrony, intraventricular delay was accepted as >60 ms, and interventricular delay was accepted as >40 ms. RESULTS: Left ventricular systolic dyssynchrony was detected in 18 patients (60%) within the narrow QRS group and in 18 patients (94%) within the wide QRS group. Interventricular dyssynchrony was detected in 17 patients (56%) within the narrow QRS group and in 18 patients (94%) within the wide QRS group. For systolic dyssynchrony, correlations existed between intraventricular delay and QRS duration (r=0.48), left ventricular end diastolic diameter (r=0.62), left ventricular end systolic diameter (r=0.61), and EF (r=-0.63). Similarly, correlations existed between interventricular delay and QRS duration (r=0.58), left ventricular end diastolic diameter (r=0.65), left ventricle end systolic diameter (r=0.64), and EF (r=-0.64). CONCLUSION: The present study suggested that systolic or diastolic dyssynchrony exists despite normal levels of QRS duration.