Association of Thrombolysis in Myocardial Infarction Myocardial Perfusion Grade with cardiovascular magnetic resonance measures of infarct architecture after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction.
BACKGROUND
Primary percutaneous coronary intervention (pPCI) routinely restores normal epicardial flow among patients with ST-segment elevation myocardial infarction (STEMI). However, impairment of myocardial perfusion frequently persists. The goal of this analysis was to determine whether impaired myocardial perfusion was associated with cardiovascular magnetic resonance-defined abnormalities in infarct architecture, including infarct size (IS), infarct surface area (ISA), infarct border zone (IBZ), and infarct complexity (IC).


METHODS
Thirty-one patients with STEMI treated with pPCI were included in the analysis. Cardiovascular magnetic resonance was performed within 7 days of presentation and repeated at 3 months. Infarct complexity was defined as the ratio of actual ISA to an idealized smooth ISA and normalized to IS.


RESULTS
Impaired Thrombolysis in Myocardial Infarction Myocardial Perfusion Grade (TMPG) (<3) was associated with larger ISA at baseline (78.2 +/- 25.3 cm(2) vs 40.3 +/- 30.3 cm(2), P = .02) and follow-up (58.8 +/- 27.5 cm(2) vs 26.3 +/- 20.2 cm(2), P = .03) and larger IBZ at follow-up (7.8% +/- 2.7% vs 4.1% +/- 3.3%, P = .02). At follow-up, ISA, when normalized to IS, was significantly higher among patients with impaired myocardial perfusion (TMPG <3) (6.9 +/- 2.5 vs 5.9 +/- 2.4 cm(2)/%, P = .03). Thrombolysis in MI myocardial perfusion grade <3 was also associated with increased IC at follow-up (52% +/- 12% vs 33% +/- 16%, P = .01).


CONCLUSIONS
Impaired TMPG is associated with larger ISA, IBZ, and increased IC. At 3 months, TMPG remained associated with ISA and IC after adjusting for IS, suggesting that impaired TMPG after pPCI is associated with infarct architecture after healing, independent of IS.
Appelbaum
Evan
E
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
Abraham
JoEllyn M
JM
Pride
Yuri B
YB
Harrigan
Caitlin J
CJ
Peters
Dana C
DC
Biller
Leah H
LH
Manning
Warren J
WJ
Gibson
C Michael
CM
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D002306:Cardiac Volume / Q000502:physiology; D003287:Contrast Media / Q000008:administration & dosage; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000187:drug effects*; D004562:Electrocardiography; D004699:Endocardium / Q000473:pathology; D005260:Female; D019786:Gadolinium DTPA; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000628:therapy*; D015428:Myocardial Reperfusion Injury / Q000175:diagnosis; D009206:Myocardium / Q000473:pathology*; D010496:Pericardium / Q000473:pathology; D011379:Prognosis; D012815:Signal Processing, Computer-Assisted; D015912:Thrombolytic Therapy; D016896:Treatment Outcome
D003287:Contrast Media; D019786:Gadolinium DTPA