The following abstract, “Electromechanical Mapping Predicts Improvement of Regional Ventricular Function in Patients With Ischemic Cardiomyopathy Undergoing Revascularization,” by Samady et al was inadvertently left out of the Scientific Sessions Abstracts supplement (Circulation. 2001;104 [suppl II]). The abstract is published in its entirety below.
MPS.64.1 Myocardial Viability Assessment in Nuclear Cardiology Wednesday, 11/14/2001 9:00 AM to 11:30 AM Team–Team 0064B
Electromechanical Mapping Predicts Improvement of Regional Ventricular Function in Patients With Ischemic Cardiomyopathy Undergoing Revascularization
Habib Samady, C Joon Choi, Michael Ragosta, Eric R Powers, Allen R Goode, Ian J Sarembock, Lawrence W Gimple, Jennifer Hunter, George A Beller, Christopher M Kramer, Denny D Watson, University of Virginia, Charlottesville, VA
Background: Markers of myocardial viability assessed by left ventricular electromechanical mapping (EMM) have been shown to correlate with non-invasive parameters of viability asessment. Whether EMM can predict improvement in regional function after myocardial revascularization is not known. Methods: Accordingly, 15 patients (12 males, age 62±8 yrs) with ischemic LV dysfunction (LVEF 0.30±0.11) underwent EMM before revascularization. Linear local shortening (LLS), unipolar voltage (UpV), and Viability Index (VI), defined as LLS x UpV/10, were measured by EMM. All patients underwent Dipyridamole/Rest gated-SPECT sestamibi (G-SPECT) before and after revascularization to measure global LVEF and regional thickening fractions (TF). Both EMM and G-SPECT images were divided into fourteen corresponding segments for comparative analysis. Results: LVEF increased from 0.30±0.11 to 0.38±0.11 (p=0.001) 4±2 months after revascularization. Of 210 available segments,199 were revascularized and had adequate data for analysis. Fifty segments with normal baseline function were excluded. Of 149 hypokinetic or akinetic segments, 63 improved function (TF 12±13% to 25±12%, P=0.001)and 86 did not (TF 11±9% to 12±10%, P=NS). Table compares EMM variables in segements which improved function to those which did not improve function after revascularization. Logistic regression analysis showed UpV and VI to be predictive of improvement of regional function (P= 0.02). A UpV of 9.6 mV had a 64% sensitivity and a 71% specificity, and a VI index of 5.0 mV% had a 61% sensitivity and 64% specificity for detecting improvement of regional function by G-SPECT. Conclusion: EMM markers of myocardial viability are predictive of improvement of regional ventricular function after revascularization in patients with ischemic cardiomyopathy⇓.