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P1-60. Two Dimensional Assessment of Right Ventricular Function Nagesh S Anavekar, David Gerson, Raymond Y Kwong, Kent Yucel, Scott D Solomon Brigham & Women's Hospital, Boston, MA Background: Right ventricular (RV) function is an important prognostic determinant in patients with cardiovascular disease. While echocardiography is used most frequently to assess RV function, it is unable to provide an accurate measure of RV ejection fraction (RVEF). Using cardiac MRI we sought to establish which commonly used 2-dimensional measures of RV function correlate most closely with volumetrically derived RVEF Methods: RV function was analyzed from 52 cardiac MRI studies. 2-dimensional parameters of RV function (longitudinal length, transverse diameters and cavity areas in end-diastole and systole), right ventricular fractional area change (RVFAC), tricuspid annular motion (TAM), and transverse fractional shortening (TFS) were obtained from the 4-chamber view. RVEF was derived from endocardial tracing of the RV chamber from the short axis images. Echocardiographic assessment of RV function was correlated with MRI findings in a subset of 15 patients. Results: RVFAC demonstrated the strongest correlation with MRI derived RVEF (r = 0.75; p<0.001); its range of values was similar to volumetrically derived RVEF. TAM (r = 0.35; p=0.01) and TFC (r = 0.42; p<0.01) were weakly correlated with RVEF. In a subset of patients who underwent echocardiography, RVFAC measured by echocardiography correlated well with RVFAC measured by MRI (r = 0.85, p <0.0001); in the same subset, echo derived RVFAC correlated well with MRI derived RVEF (r=0.76, p<0.001). Conclusions: Right ventricular fractional area change is the best two- dimensional echocardiographic correlate of MRI derived RV ejection fraction, and thus may represent a simple yet accurate method for the objective assessment of RV function. Poster Session 2 Monday, June 28 2:00 pm - 5:00 pm Moderated Posters: Ischemic Heart Disease: Rest and Stress - Posters P2-01 through P2-12 Posters: Contrast Echocardiography: Techniques & Applications (II) - Posters P2-13 through P2-24 3D Echocardiography: Techniques & Applications (I) - Posters P2-25 through P2-35 Diastolic Function (I) - Posters P2-36 through P2-49 Cardiomyopathies/Pericardial Diseases - Posters P2-50 through P2-62 P2-01. Moderated Poster Relationship between Myocardial Ischemia Assessed by Stress Echocardiography and Implantable Cardioverter Defibrillator Therapy in Patients with Coronary Heart Disease Abdou Elhendy, John R Windle, Thomas R Porter University of Nebraska medical Center, Omaha, NE Background. The detection of precipitating factors for sustained ventricular arrhythmias in patients (pts) with implantable cardioverter defibrillator (ICD) may have important therapeutic implications. The relationship between myocardial ischemia on current stress imaging techniques and arrhythmic events in these pts has not been evaluated. Aim of this study was to assess the relation between myocardial ischemia during stress echocardiography and major events in pts with ICD. Methods. We studied 85 pts (age = 64 ± 13 years, 25 women) with history of coronary artery disease who received ICD for primary (55 pts) or secondary (30 pts) prevention of sudden cardiac death. Seventy two (82%) pts had previous myocardial revascularization. Pts underwent stress echocardiography (symptom limited exercise treadmill in 13 pts or dobutamine up to 50 μg/kg/min/atropine up to 2 mg in 72 pts). Ischemia was defined as new or worsening wall motion abnormalities. End points during follow up were death and appropriate ICD therapy. Pts who had subsequent revascularization were censored. Results. Mean ejection fraction was 36 ± 12%. Ischemia was detected in 37 (44%) pts. During a mean follow up of 2.1 ± 1.2 years, 5 pts died and 19 pts had ICD therapy. Ischemia was detected in 20 of 24 pts with subsequent events and in 17 of 43 pts without events (83% vs 40%, p <0.001). In a Cox multivariate analysis model of clinical and echocardiographic data, independent predictors of events were a history of spontaneous sustained ventricular tachycardia (chi 2 = 3.8, p<0.01) and myocardial ischemia (chi 2 = 5, p<0.001). Conclusion. Myocardial ischemia during stress echocardiography is an independent predictor of death and ICD therapy in patients with coronary heart disease. P2-02. Moderated Poster Impact of Improvement in Global Left Ventricular Systolic Function On Long- term Outcome in Patients with Ischemic Ventricular Dysfunction Irshad Alam, Jo Mahenthiran, Irmina Gradus-Pizlo, Masoor Kamalesh, Adam Greene, Harvey Feigenbaum, Stephen G Sawada Indiana University, Indianapolis, IN Background: In patients with viable myocardium, revascularization (revasc) has been shown to improve the prognosis of these patients with coronary disease (CAD) and left ventricular (LV) dysfunction. Improvement of global function in these patients is thought to be the mechanism for improved prognosis but prior studies have shown conflicting data. We examined the long-term prognostic effect of improvement in ejection fraction (EF) with revasc in patients with viable myocardium. Methods: Seventy patients with CAD and LV dysfunction had dobutamine echo (DE) before revasc with assessment of low dose Dobutamine stress wall motion scores. Post revasc echocardiograms were obtained and pre and post revasc EF by biplane Simpson’s technique. Long-term outcome (endpoint of cardiac death) was compared between patients with and without significant (defined as > 5 %) improvement in EF. Follow up echocardiogram was obtained in all patients (mean 512 days after revasc). The follow up was for 1719 + 971 days. Results: The mean age was 59 + 9 years(48 males). The mean pre and post revasc EF were similar (32% vs. 34%, p=NS).The Sixty nine patients had multivessel CAD and had CABG after DE and one had PTCA.Fourty one (58%) patients had > 5% improvement in EF after revasc and 29(42%) had no significant improvement.Patients with significant EF improvement had lower pre revasc rest (2.14 vs 1.96, p = 0.024) and low dose (1.91 vs 1.76, p = 0.048) wall scores compared to those without significant EF improvement. There were a total of 18 deaths recorded. Survival curves showed improved outcome of patients with improved EF during our follow up period (see Figure, solid line – pts with improved EF, dashed line pts without EF improvement, p value = 0.02. Conclusion: Patients with viable myocardium who have improvement in EF with revasc have better long-term survival. Improvement in global LV function may contribute to the survival advantage of revasc. Journal of the American Society of Echocardiography 512 Abstracts May 2004
