Prospective Minnesota Study of ECHO Tissue Doppler Imaging in Cardiac Resynchronization Therapy

Cardiac Resynchronization Therapy (CRT) is a newly developed therapy designed to improve outcomes in patients with heart failure(HF). Recent studies have shown significant symptomatic improvement and a decrease in hospitalization and mortality with CRT. However, up to 30 % of patients do not experience improvement with this invasive and costly therapy. Tissue Doppler Imaging (TDI) is emerging as an effective tool for non-invasively assessing mechanical dyssynchrony of the left ventricle (LV) and may aid in the identification of LV mechanical dyssynchrony to predict clinical response to CRT. PROMISE-CRT is designed to address the following hypothesis: Changes in tissue doppler imaging measures of left ventricular mechanical dyssynchrony from baseline to one week following cardiac resynchronization therapy will correlate with the clinical response at three months. Seventy HF patients clinically indicated to receive CRT will be enrolled in this six-month multi-center study conducted in the Minneapolis-St. Paul metropolitan area. TDI analyses, measures of clinical improvement and LV remodeling will be conducted one week, three months, six months after CRT implementation.