Restoration of myocardial blood flow following percutaneous coronary balloon dilatation and stent implantation: assessment with qualitative and quantitative contrast-enhanced magnetic resonance imaging.
OBJECTIVE
To examine the serial use of magnetic resonance imaging (MRI) to evaluate regional myocardial perfusion changes following percutaneous coronary angioplasty and stent implantation (PTCA).


METHODS
Six patients with single vessel coronary artery disease (CAD) underwent contrast-enhanced first pass MRI immediately prior to (visit A) and within 7 days after (visit B) PTCA. Three sequential short axis slices were obtained after gadodiamide (Gd) bolus (0.025 mmol/kg(-1)) at rest and during adenosine. Each short axis was divided radially into eight regions of interest (ROIs). ROIs were anatomically assigned to a coronary artery territory (CAT). Stress and rest qualitative and quantitative (unidirectional extraction fraction constant (K(i)); index of myocardial perfusion reserve (MPRI) = stressK(i) / restK(i)) perfusion parameters were determined for ROI supplied by remote and stenosed/stented vessels for each visit.


RESULTS
In stented ROIs the number of ROIs demonstrating normal perfusion, as opposed to reversible perfusion deficits, increased. Qualitative perfusion assessment in remote CATs was unchanged. MPRI in stenotic CATs was lower than in remote CATs at visit A (P < 0.001). Following PTCA, MPRI increased in stented CATs (P < 0.001) but was unchanged in remote CATs.


CONCLUSIONS
Restoration of myocardial perfusion following PTCA can be delineated with qualitative and quantitative perfusion MRI. Although at present the investigation is technically complex and not perfectly sensitive or specific, MRI has the potential to be a valuable tool for patient follow-up and evaluation of revascularization strategy efficacy.
Sensky
P R
PR
Department of Cardiology, University of Leicester, Glenfield Hospital, Leicester, UK. pen.sensky@ntlworld.com
Samani
N J
NJ
Horsfield
M A
MA
Cherryman
G R
GR
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003287:Contrast Media; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology / Q000628:therapy*; D003331:Coronary Vessels / Q000503:physiopathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015607:Stents; D016896:Treatment Outcome
D003287:Contrast Media