Territorial Post-Revascularization Remodeling of Chronic Coronary Syndromes: Cardiac Magnetic Resonance Feature Tracking Study

BackgroundMRI feature-tracking (MRI-FT) can accurately assess ventricular myocardial deformation and regional function and may be a better predictor of mortality than ejection fraction and infarct extension. However, role of MRI-FT in assessing coronary revascularization is unclear.PurposeTo assess coronary revascularization effect on territorial left ventricle (LV) function of chronic coronary syndrome (CCS) patients by MRI-FT.Study TypeProspective.Subjects50 CCS patients (age: 62.22 +/- 8.70 years) scheduled for elective percutaneous coronary intervention (PCI), and 30 healthy controls (age: 35.33 +/- 11.57 years).Field Strength/Sequence1.5T with balanced steady-state free precession cine sequence.AssessmentGlobal and segmental peak systolic longitudinal, circumferential, and radial myocardial strains were quantified in both patient and healthy control groups by an experienced operator using dedicated software. Patients were studied both pre-PCI and 6-month post-PCI and LV territorial myocardial strain values were calculated by averaging the segmental values of each revascularized territory.Statistical TestsStudent's t-test, paired t-test, Mann Whitney test, and Wilcoxon signed ranks test. Significance was judged at the 5% level.ResultsTerritorial longitudinal strain showed significant 6-month post-PCI improvement in the left anterior descending (LAD) and right coronary artery (RCA) territories, but there was not in the left circumflex (LCX) territory (LAD: mean - 11.41% +/- 3.45% pre, -13.01% +/- 3.53% post; RCA: mean - 11.11% +/- 2.65% pre, -13.25% +/- 2.81% post; and LCX: mean - 15.43% +/- 3.97% pre, -16.17% +/- 4.38% post, P = 0.215). Territorial circumferential strain showed significant post-PCI improvement in all revascularized territories (LAD: mean - 13.73% +/- 6.56% pre, -16.98% +/- 6.01% post; LCX: mean - 13.23% +/- 4.23% pre, -16.34% +/- 3.45% post; and RCA: mean - 11.24% +/- 3.36% pre, -13.80% +/- 3.51% post). Territorial radial strain showed no significant post-PCI improvement (LAD: mean 22.73% +/- 12.38% pre, 21.79% +/- 11.55% post, P = 0.541; LCX: mean 27.73% +/- 7.95% pre, 29.0% +/- 7.25% post, P = 0.264; and RCA: mean 36.68% +/- 11.10% pre, 31.75% +/- 10.95% post, P = 0.208).Data ConclusionTerritorial LV systolic function was significantly improved by coronary revascularization in CCS patients.Level of Evidence1Technical EfficacyStage 4

Automated summary

MRI-FT can be used to assess the effect of coronary revascularization on territorial left ventricular function in patients with chronic coronary syndrome. The study found that coronary revascularization significantly improved territorial circumferential strain, but had no significant effect on territorial longitudinal and radial strains.