Potential of an intracardiac electrogram for the rapid detection of coronary artery occlusion.
BACKGROUND
Early identification of acute MI and prompt intervention can improve clinical outcomes. It would be valuable to identify a method that could allow the earliest possible detection of myocardial injury or ischemia.


RESULTS
This article reports one of the first clinical investigations to examine the ability of an intracardiac right ventricular (RV) electrode to identify the early onset of myocardial ischemia/injury in a cohort of patients undergoing balloon occlusion of a coronary artery during percutaneous transluminal coronary angioplasty. The primary data set for analysis included observations from 14 patients with 17 lesions, with a matched comparison of a V6 surface lead and the RV to left upper chest, "intracardiac" lead. The intracardiac lead was sensitive in detecting myocardial injury current/ischemia. There was a 36.4+/-5.6% ST-segment shift, relative to the amplitude of the QRS complex, in the intracardiac lead at 2 min, compared with a 10.1+/-1.9% ST shift from a surface lead (P=.00011). The RV to left upper chest lead detected a >10% shift in ST segment within 2 min in 17 (100%) of 17 cases vs. 8 (47%) of 17 for a V6 surface lead. The intracardiac lead provided detection of ischemia in all three major epicardial coronary distributions.


CONCLUSIONS
This study demonstrates the ability of an intracardiac (RV apex to left upper chest) lead to rapidly detect myocardial ischemia/injury during acute coronary occlusion in the setting of balloon angioplasty. The results of this study suggest that a simple implantable system resembling a ventricular pacemaker could be programmed to assist in the very early diagnosis of acute myocardial infarction.
Fischell
Tim A
TA
Borgess Heart Institute, Kalamazoo, MI 49048, USA. taf1@net-link.net
Fischell
David R
DR
Fischell
Robert E
RE
Baskerville
Susan
S
Hendrick
Susan
S
Moshier
Carol
C
Harwood
Jonathan P
JP
Krucoff
Mitchell W
MW
D000704:Analysis of Variance; D000800:Angioplasty, Balloon / Q000379:methods; D021721:Balloon Occlusion / Q000009:adverse effects / Q000379:methods; D015331:Cohort Studies; D017023:Coronary Angiography / Q000379:methods; D003327:Coronary Disease / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy*; D003331:Coronary Vessels / Q000503:physiopathology*; D004562:Electrocardiography / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D005240:Feasibility Studies; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000503:physiopathology; D010138:Pacemaker, Artificial; D010865:Pilot Projects; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors