Relationship between intraventricular cardiac asynchrony and degree of systolic dysfunction.

OBJECTIVES

Cardiac asynchrony is an area of study becoming more relevant in the evaluation and management of heart failure. Our aim was to determine the prevalence of cardiac asynchrony by Doppler echocardiography and to evaluate its relationship with the degree of left ventricular (LV) systolic dysfunction.

METHODS

A total of 316 consecutive patients with LV ejection fraction less than 40% were enrolled. We divided them into 3 groups according to the degree of LV dysfunction: 31% to 40%, 21% to 30%, and less than 20%. Intraventricular asynchrony was evaluated using two methods: (1) measurement of the septal to posterior wall-motion delay (cut-off point 130 milliseconds); and (2) measurement of the difference between time from Q wave to LV ejection end, and the time from Q wave to the end of the systolic wave of the most delayed basal segment by Doppler tissue imaging (ejection- Doppler tissue imaging time; cut-off point 50 milliseconds).

RESULTS

Mean age was 62.14 +/- 13.5 years (75.7% men). No differences were found among clinical electrical and echocardiographic variables among the groups. Furthermore, no relationship was found between the existence of intraventricular cardiac asynchrony and the degree of LV systolic dysfunction. These were similar in patients with ischemic dilated cardiomyopathy and nonischemic dilated cardiomyopathy.

CONCLUSIONS

The degree of LV systolic dysfunction and its origin are not related to the presence of cardiac asynchrony. A specific echocardiographic Doppler study must always be performed to assess the existence of cardiac asynchrony in those who are candidates to resynchronization therapy.