Continuously Updated 124ead ST-Segment Recovery Analysis for Myocardial Infarct Artery Patency Assessment and Its Correlation with Multiple Simultaneous Early Angiographic Observations Mitchell W. Krucoff, MD, Martha A. 0011, RN, James E. Pope, MD, Karen S. Pieper, MS, Prapti M. Kanani, MD, Christopher B. Granger, MD, Rolf F. Veldkamp, MD, Beverly L. Wagner, RN, Sharon T. Sawchak, RN, and Robert M. Califf, MD Early aw@imaW mf not adequaW subgroup patients with myocardiil infarction if cyclic changesinwronary flow occur hequently. Prom a pilot experience using a new U-lead ST-seg- ment monitor, a continuously updated, B enced ST-very analysis method was deveC oped to quantii both instantaneous recovery, as a noninvasive marker of patency, and cumulative ST recovery over time, as a madfee of the speed, stabilii and duration of reperfusion. In 22 patientswithacuteinfarcbninwhom44~ vatiis of unique an@@aphic patency were noted within 6 hours of presentatii, serial patency -nts simultaneous with all angbgk@ic observations predicted coronary occlusion with 90% sensitivity and 92% !spedfici- ty.Ofthe 22 patientqll(5o%)had multipleS1 trend transitions suggesting cyclic changes in 4zomauyflow hefom cathetedation. speed, sta bility and duration of ST%e@nent recovery were defined by the time to first 50% ST recover, total number of ST-trend transitions and patent physiolo$y index (percentag 8 of monitoring peri- od showing ST recovery), respectively. Sub grouped wically, the median (interquar- tile range) for cumulative ST parameters with patent (n = 8) versus occluded (n = 14) arteries were, respedvely - time to !M% recovery, 1.57 (1.16,1.70) versus 0.17 (4.47, 0.22) hours; num berofreelevatii/recovery events, i.5 (1,3) versus3 (1,3);andpatentphysiolo@ index,52 (47, 59) versus 50 (5, 73). Thus, continuous ST- se@nent recovery analysis appears to predict simultaneous Bphic patency over serial arraraments, whereas cumulative parameters appear to contain independent Mormation, prob ablybecauS8OfpEde+llC~chang6Sbefon,Orafter angi*phy. (Am J Cardiil199371:~l51) From the Cardiology Division, Duke University Medical Center, Dur- ham, North Carolina. Manuscript received July 20, 1992; revised man- uscript received August 28, 1992, and accepted August 30. Address for reprints: Mitchell W. Krucoff, MD, Duke University Medical Center, Hospital North Box 3968, Durham, North Carolina 27710. ngiographically defined patency provides only a Ad brief anatomic visualization of the infarct artery uring the course of ongoing infarction. More prolonged angiography has shown that cyclic or “unsta- ble” infarct artery patency is common and consistently related to dynamic ST-segment changes.1,2 Quantifica- tion of the ST-segment recovery process may provide both an instantaneous method for serial patency assess- ments and a cumulative measure of the speed and sta- bility of reperfusion. Analytic methods for ST analysis in patients presenting with abnormal ST levels subject to sudden marked changes are limited.3-7 To address this need, we developed a method of self-referenced, con- tinuously updated ST-segment recovery analysis paired with a new 1Zlead digital ST monitor and examined its performance in patients who underwent acute angiogra- phy during myocardial infarction. The goal of this ret- rospective analysis was to examine, in a preliminary fashion, the relation of ST-recovery analysis to simulta- neous infarct artery patency and the relation of cumula- tive ST recovery reflecting speed, stability and duration of reperfusion to acute angiographic patency. METHODS Patient selection: All patients presented with chest pain within 6 hours and ST-segment elevation not re- versed with nitrates, as previously detailed.8 All patients had myocardial infarction by enzyme elevation and all underwent cardiac catheterization within 6 hours of ad- mission. Choice of therapy and timing of catheterization were determined either through physician judgment or through the Thrombolysis and Angioplasty in Myocar- dial Infarction (TAMI) 5 protocol.9 ST-segment moni- toring data were not accessible to the bedside caretak- ers in any case. -graphic analysis: For this analysis the infarct artery was detined as patent with Thrombolysis in Myo- cardial Infarction (TIMI) trial 2 to 3 flow, or as occlud- ed with TIMI trial 0 to 1 flow. Unique angiographic observations were included for every patient in whom patency change (from patent to occluded or vice versa) occurred during catheterization, either spontaneously or as a result of further therapy. TIMI flow was determined by experienced angiographers (non-TAMI patients) or by the TAMI Angiographic Core Laboratory at the Uni- versity of Michigan (TAMT 5 patients). In all cases ST-SEGMENT RECOVERY ANALYSIS 145