Results of the PROspective MInnesota Study of ECHO/TDI in Cardiac Resynchronization Therapy (PROMISE-CRT) Study ALAN J. BANK, MD, 1,2,4 CHRISTOPHER L. KAUFMAN, PhD, 2 AARON S. KELLY, PhD, 2,4 KEVIN V. BURNS, BS, 2 STUART W. ADLER, MD, 2 TOM S. RECTOR, PhD, 3,4 STEVEN R. GOLDSMITH, MD, 1,4 MARIA-TERESA P. OLIVARI, MD, 1 CHUEN TANG, MD, 1 LINDA NELSON, RN, 2 AND ANDREA METZIG, MA, 2 ON BEHALF OF THE PROMISE-CRT INVESTIGATORS Minneapolis, Minnesota ABSTRACT Background: Retrospective single-center studies have shown that measures of mechanical dyssynchrony before cardiac resynchronization therapy (CRT), or acute changes after CRT, predict response better than QRS duration. The Prospective Minnesota Study of Echocardiographic/TDI in Cardiac Resynchronization Therapy (PROMISE-CRT) study was a prospective multicenter study designed to determine whether acute (1 week) changes in mechanical dyssynchrony were associated with response to CRT. Methods and Results: Nine Minnesota Heart Failure Consortium centers enrolled 71 patients with standard indications for CRT. Left ventricular (LV) size, function, and mechanical dyssynchrony (echocar- diography [ECHO], tissue Doppler imaging [TDI], speckle-tracking echocardiography [STE]) as well as 6-minute walk distance and Minnesota Living with Heart Failure Questionnaire scores were measured at baseline and 3 and 6 months after CRT. Acute change in mechanical dyssynchrony was not associated with clinical response to CRT. Acute change in STE radial dyssynchrony explained 73% of the individual var- iation in reverse remodeling. Baseline measures of mechanical dyssynchrony were associated with reverse remodeling (but not clinical) response, with 4 measures each explaining 12% to 30% of individual vari- ation. Conclusions: Acute changes in radial mechanical dyssynchrony, as measured by STE, and other baseline mechanical dyssynchrony measures were associated with CRT reverse remodeling. These data support the hypothesis that acute improvement in LV mechanical dyssynchrony is an important mechanism contrib- uting to LV reverse remodeling with CRT. (J Cardiac Fail 2009;-:1e9) Key Words: heart failure, pacemakers, echocardiography, reverse remodeling. Cardiac resynchronization therapy (CRT) improves symptoms, functional status, ventricular size and function, hospitalization rate, and mortality in patients with advanced heart failure. 1e4 However, approximately 25% to 30% of patients who meet standard criteria for CRT fail to derive substantial benefit. One potential explanation is that electri- cal dyssynchrony, as measured by QRS duration, rather than mechanical dyssynchrony, has been used as a major criterion for receiving a CRT device. Several retrospective studies have shown that, as compared with QRS duration, preimplant tissue Doppler imaging (TDI) 5e7 or speckle tracking echocardiography (STE) 8e10 indices of mechani- cal dyssynchrony have superior sensitivity and specificity for identifying patients who benefit. The only prospective multicenter trial examining preimplant echocardiographic/ TDI measures of mechanical dyssynchrony failed to show clinically significant sensitivity and specificity for predict- ing response to CRT. 11 Previous retrospective analyses have shown that acute re- synchronization of LV mechanical dyssynchrony is associ- ated with LV reverse remodeling 12 and long-term clinical response. 13 However, no prospective studies have examined the relationship between acute resynchronization and From the 1 Minnesota Heart Failure Consortium, Minneapolis, Minneso- ta; 2 The St. Paul Heart Clinic, St. Paul, Minnesota; 3 Minneapolis VA Med- ical Center and 4 University of Minnesota, Minneapolis, Minnesota. Manuscript received November 24, 2008; revised manuscript received December 12, 2008; revised manuscript accepted December 17, 2008. Correspondence to: Alan J. Bank, MD, St. Paul Heart Clinic, 225 N. Smith Avenue, #400, St. Paul, MN 55102. Phone: 651-726-6767; Fax: 651-233-5080. E-mail: abank@stphc.com Supported by a grant from Guidant Corporation (now Boston Scientific). Drs Bank, Kaufman, Kelly, and Adler receive honoraria and/or research grant support from Medtronic and Boston Scientific. Linda Nelson is cur- rently an employee at Medtronic, Inc. All other authors report no conflict of interest. 1071-9164/$ - see front matter Ó 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.cardfail.2008.12.009 1 Journal of Cardiac Failure Vol. - No. - 2009 ARTICLE IN PRESS