Association of the timing of ST-segment resolution with TIMI myocardial perfusion grade in acute myocardial infarction C. Michael Gibson, MS, MD, a Juhana Karha, MD, a Robert P. Giugliano, MD, SM, a Mathew T. Roe, MD, b Sabina A. Murphy, MPH, a Robert A. Harrington, MD, b Cindy L. Green, PhD, b Marc J. Schweiger, MD, c Jerry S. Miklin, MD, d Kenneth W. Baran, MD, e Sebastian Palmeri, MD, f Eugene Braunwald, MD, a and Mitchell W. Krucoff, MD, b for the INTEGRITI Study Group Boston and Springfield, Mass, Durham, NC, Wheat Ridge, Colo, St Paul, Minn, and New Brunswick, NJ Background More complete ST-segment resolution (ST res) in acute myocardial infarction (MI) has been associated with better epicardial and myocardial reperfusion as assessed with the Thrombolysis in Myocardial Infarction (TIMI) flow grade (TFG) and the TIMI myocardial perfusion grade (TMPG), respectively. However, no data exist comparing the speed of ST resolution on continuous electrocardiogram (ECG) monitoring with the TMPG on coronary angiography. We hypoth- esized that delayed ST res is associated with impaired TMPGs. Methods Continuous 12-lead ECG recordings and 60-minute angiographic data were analyzed in 120 patients with acute MI who received tenectaplase monotherapy or combination therapy with low-dose tenectaplase and eptifi- batide in the Integrilin and Tenecteplase in Acute Myocardial Infarction (INTEGRITI) trial. Results More rapid ST res on continuous ECG monitoring was associated with improved TMPGs on coronary angiog- raphy performed 60 minutes after study drug administration. For TMPG 3, the median time to ST resolution was 53 min- utes. For TMPG 2, 1, and 0, the corresponding times were 64 minutes, 80 minutes, and 106 minutes, respectively (P = .01 for trend). Likewise, more rapid ST res was also associated with faster epicardial flow. For TFG 3, the median time to ST resolution was 46 minutes, compared with 109 minutes for TIMI flow grades 0 to 2 (P = .001). The corresponding times for a corrected TIMI frame count 40 versus 40 were 52 minutes and 112 minutes, respectively (P .001). Conclusions Although the static ECG has been associated with epicardial and myocardial blood flow in the past, this study extends these observations to demonstrate that more rapid ST res on continuous ECG monitoring is associated with improved myocardial perfusion after thrombolytic administration. (Am Heart J 2004;147:847–52.) To advance the growing field of device studies in ST elevation myocardial infarction (MI), valid surrogate biomarkers are needed because multiple large-scale mortality trials are not likely given cost constraints. One measure of successful reperfusion after fibrino- lytic administration is the extent of ST-segment resolu- tion on the static 12-lead electrocardiogram (ECG). 1 Greater ST resolution on the static ECG has been re- lated to smaller subsequent infarct size, improved in- farct zone wall motion, 2,3 and improved survival rate. 4,5 Likewise, studies of continuous ECG monitor- ing have associated faster and more complete ST reso- lution with better clinical outcome 6,7 and a greater likelihood of infarct-related artery patency and blood flow, as assessed with Thrombolysis in Myocardial In- farction (TIMI) flow grade (TFG). 8,9 Furthermore, greater ST resolution on a static ECG has been related to improved myocardial reperfusion as assessed with the TIMI myocardial perfusion grade (TMPG). 10,11 Al- though static ECG studies have been used to demon- strate the importance of the magnitude of ST resolu- tion, little data exist comparing the speed of ST resolution on continuous ECG monitoring with myo- cardial perfusion on the angiogram. We hypothesized that delayed ST resolution on continuous ST segment monitoring would be associated with impaired TMPGs on coronary angiography. From the a TIMI Study Group, the Department of Medicine, Brigham & Women’s Hospi- tal, Boston, Mass, b Duke Ischemia Monitoring Laboratory, Duke Clinical Research Insti- tute, Durham, NC, c Baystate Medical Center, Springfield, Mass, d Rocky Mountain Heart Associates, Wheat Ridge, Colo, e St. Paul Heart Clinic, St. Paul, Minn, and f Rob- ert Wood Johnson Medical School, New Brunswick, NJ. Supported in part by a grant from Millenium Pharmaceuticals, Cambridge, Mass. Submitted August 28, 2003; accepted October 28, 2003. Reprint requests: C. Michael Gibson, MS, MD, Director TIMI Data Coordinating Cen- ter, 350 Longwood Ave, 1st Floor, Boston MA 02115. 0002-8703/$ - see front matter © 2004, Elsevier Inc. All rights reserved. doi:10.1016/j.ahj.2003.11.015