Accuracy of Area at Risk Quantification by Cardiac Magnetic Resonance According to the Myocardial Infarction Territory.
OBJECTIVE
Area at risk (AAR) quantification is important to evaluate the efficacy of cardioprotective therapies. However, postinfarction AAR assessment could be influenced by the infarcted coronary territory. Our aim was to determine the accuracy of T2-weighted short tau triple-inversion recovery (T2W-STIR) cardiac magnetic resonance (CMR) imaging for accurate AAR quantification in anterior, lateral, and inferior myocardial infarctions.


METHODS
Acute reperfused myocardial infarction was experimentally induced in 12 pigs, with 40-minute occlusion of the left anterior descending (n = 4), left circumflex (n = 4), and right coronary arteries (n = 4). Perfusion CMR was performed during selective intracoronary gadolinium injection at the coronary occlusion site (in vivo criterion standard) and, additionally, a 7-day CMR, including T2W-STIR sequences, was performed. Finally, all animals were sacrificed and underwent postmortem Evans blue staining (classic criterion standard).


RESULTS
The concordance between the CMR-based criterion standard and T2W-STIR to quantify AAR was high for anterior and inferior infarctions (r = 0.73; P = .001; mean error = 0.50%; limits = -12.68%-13.68% and r = 0.87; P = .001; mean error = -1.5%; limits = -8.0%-5.8%, respectively). Conversely, the correlation for the circumflex territories was poor (r = 0.21, P = .37), showing a higher mean error and wider limits of agreement. A strong correlation between pathology and the CMR-based criterion standard was observed (r = 0.84, P < .001; mean error = 0.91%; limits = -7.55%-9.37%).


CONCLUSIONS
T2W-STIR CMR sequences are accurate to determine the AAR for anterior and inferior infarctions; however, their accuracy for lateral infarctions is poor. These findings may have important implications for the design and interpretation of clinical trials evaluating the effectiveness of cardioprotective therapies.
Área de Fisiopatología Vascular, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Unidad de Imagen Cardiaca Avanzada, Departamento de Cardiología, Hospital Universitario HM Montepríncipe, Madrid, Spain.
Leticia
L
Fernández-Friera
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Departamento de Cardiología, Hospital Universitario Central de Asturias, Oviedo, Asturias, Spain.
José Manuel
JM
García-Ruiz
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Unidad de Insuficiencia Cardiaca, Departamento de Cardiología, Hospital Clínic, Barcelona, Spain.
Ana
A
García-Álvarez
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Departamento de Cardiología, Hospital Clínico San Carlos, Madrid, Spain.
Rodrigo
R
Fernández-Jiménez
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Departamento de Ciencia Clínica, Philips Healthcare Iberia, Madrid, Spain.
Javier
J
Sánchez-González
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; The Hatter Cardiovascular Institute, Institute of Cardiovascular Science, University College London, United Kingdom.
Xavier
X
Rossello
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Servicio de Cardiología, IIS-Hospital Universitario Fundación Jiménez Díaz, Madrid, Spain.
Sandra
S
Gómez-Talavera
Área de Fisiopatología del Miocardio, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain.
Gonzalo J
GJ
López-Martín
Área de Fisiopatología Vascular, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Departamento de Cardiología, Complejo Hospitalario Ruber Juan Bravo, Universidad Europea de Madrid (UEM), Madrid, Spain.
Gonzalo
G
Pizarro
Área de Fisiopatología Vascular, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Department of Cardiology, Zena and Michael A. Wiener Cardiovascular Institute, Mount Sinai School of Medicine, New York, United States.
Valentín
V
Fuster
Área de Fisiopatología Vascular, Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain; Servicio de Cardiología, IIS-Hospital Universitario Fundación Jiménez Díaz, Madrid, Spain. Electronic address: bibanez@cnic.es.
Borja
B
Ibáñez
D000818:Animals; D004195:Disease Models, Animal; D008279:Magnetic Resonance Imaging; D008297:Male; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D018570:Risk Assessment; D013552:Swine; D013997:Time Factors
Imagen; Imaging; Infarto de miocardio; Isquemia miocárdica; Magnetic resonance imaging; Myocardial infarction; Myocardial ischemia; Resonancia magnética