Abstract 17602: Mechanical Dyssynchrony in Non-Compaction Cardiomyopathy: Underlying Mechanism for Improved Response to CRT, Even With Narrow QRS
Abnormal myocardial development, such as in noncompaction cardiomyopathy (NCM), may lead also to concomitant abnormal activation and electromechanical coupling due to hypertrabeculation and altered Purkinje system topology. The aim of our study is to asses the presence of ventricular mechanical dyssynchrony in NCM and the potential usefulness of cardiac resynchronization therapy (CRT) in those patients, a lot of which have a narrow QRS complex.
Methods: We studied 25 patients consecutively diagnosed with NCM and a control group of 25 patients with dilated cardiomyopathy of different etiologies and narrow QRS. The presence of a septal flash was used as an echocardiographic marker of ventricular dyssynchrony. Patients were classified based on QRS width: wide QRS>120 ms and narrow QRS<120 ms. In the subgroup of patients with NCM, 10 received CRT and were followed up at 6 and 12 months. Response to CRT was defined as a reduction >15% of left ventricular end-systolic volume.
Results: Overall, a septal flash was observed in 68% of patients with NCM while only in 8% of controls (Figure 1). Among the 10 patients with NCM treated with CRT, all of them showed a septal flash and favorable response was observed in 7/8 (87%) of patients at follow-up regardless of QRS width (narrow QRS: response 4/4 and wide QRS response 3/4).
Conclusions: The presence of mechanical dyssynchrony, correctable with CRT, is common in the group of patients with NCM, independently of the QRS width. NCM seems to be an etiology of heart failure with narrow QRS with a high response to CRT.
- © 2010 by American Heart Association, Inc.