[Analysis of inter- and intraventricular asynchrony by tissue Doppler echocardiography]

Cardiac resynchronization therapy (CRT) is a promising non-pharmacological treatment option for patients (pts) with severe severe heart failure (CHF), systolic left ventricular (LV) dysfunction, and ventricular conduction abnormalities (VCA). Pt selection for CRT, however, is still controversial. Tissue Doppler echocardiography (TDE) can be used to analyze regional wall motion with high temporal resolution.

In 33 CHF pts with VCA (QRS width > or =140 ms) and 20 normal probands, left and right ventricular (RV) filling and emptying were analyzed by flow and tissue Doppler to assess regional (anterior, lateral, inferior, and septal) asynchrony within the LV as well as asynchrony between the RVand LV. All time measurements were corrected for a heart rate of 60 bpm. Results Maximum interventricular and segmental intraventricular delay was 30 ms in the normals. LV asynchrony, defined as a regional delay of > or =40 ms, was found in 29/33 (88%) of the CHF pts, in 4 cases there was synchronous LV contraction despite VCA. In the pts with LV asynchrony, 22 (67%) showed the maximum delay in the lateral wall, 7 (21%) in the septum. Inter- and intra-ventricular asynchrony correlated weakly.

In many CHF pts with VCA, there is a delay both between the two ventricles, and among different LV regions. Predominantly but not exclusively, the LV lateral wall shows the maximum intra-LV delay. Some CHF pts, however, seem to have a synchronous LV contraction despite VCA. TDE thus adds important information for pt selection with respect to CRT.