RESUMEN
Objective Myocardial functional outcome after revascularization of coronary chronic total occlusion (CTO) was prospectively predicted using extracellular volume fraction (ECV) based on cardiovascular magnetic resonance (CMR). Methods Thirty patients with CTO underwent CMR before and 6 months after percutaneous coronary intervention (PCI) were enrolled. The CMR scan protocol included cine, pre?contrast and post?contrast T1 mapping and late gadolinium enhancement (LGE). Ejection fraction (EF) and segmental wall thickening (SWT) were calculated using CVI 42 software. SWT less than 45% indicated myocardial segment dysfunction. According to the American Heart Association (AHA) scientific statement, the dysfunctional segments assigned to CTO vessel were selected, and three baseline imaging markers, ECV, transmural extent of infarction (TEI) and unenhanced rim thickness (RIM) were respectively evaluated. The myocardial segments were divided into two subgroups, group with well?developed collaterals and group with poorly?developed collaterals, based on the collateral circulation using Rentrop classification. Baseline and follow?up values of SWT and EF were evaluated using paired Student′s t?test. Using an increase in SWT>10% as standard reference, ROC analysis was conducted to describe the predictive performance of baseline markers. A mixed linear model was used to probe the relationship between collateral circulation and SWT. Stepwise logistic regression analysis was used to determine the independent predictors of regional functional recovery. The differences of EF between poorly?developed and well?developed collaterals were compared by Student t test. Results The baseline mean segmental wall thickening (SWT) of the dysfunctional segments increased from 21.6% (9.7%, 33.3%) to 38.4% (19.0%, 51.2%) after PCI (Z=-6.869, P<0.001), and EF was also significantly higher compared with baseline (54.5%±8.5 % vs. 50.7%± 6.6%, t=-5.706, P<0.001). ECV showed good performance in predicting functional recovery with cutoff value 34.7%, area under ROC curve (AUC) 0.86, sensitivity 91%, and specificity 66%. The AUC of ECV was superior to TEI and RIM (AUC: 0.75 and 0.73, all P value<0.01). The segments with well?developed collaterals were associated with a higher SWT at follow?up [46.6% (36.6%, 64.2%) vs. 33.5% (12.8%, 47.8%),F=5.791, P=0.02]. Logistic regression analysis demonstrated that mean segmental ECV was the only independent predictors of regional functional outcome after PCI (OR=0.83, 95% confidence interval: 0.77—0.89; P<0.001). Conclusions ECV by CMR may provide incremental value for the prediction of regional functional recovery in CTO patients, and baseline collateral circulation correlates with the regional systolic function after revascularization.
RESUMEN
Objective To study the possible influencing factors in the formation of coronary collateral circulation in patients with chronic total occlusion (CTO). Methods Patients were enrolled having at least 1 major coronary artery angiography revealed as CTO of 144 patients. According to the Rentrop classification, patients with grade 0 and grade 1 filling were catogorized as insufficient collateral circulation group (n=72) and patients with grade 2 and grade 3 filling as collateral circulation group (n=72). Serum biomarkers and insulin-resistance by HOMA model were also studied in all patients. Results In the insufficient collateral circulation, BMI,TC,ApoB, lipoprotein a, fasting insulin HOMA-IR,HOMA- beta, CRP was significantly higher than the well collateral circulation group and ApoA-Ⅰ, ISI lower than the well collateral group ( all P ﹤0. 05 ) . Bivariate correlation alaysis showed. Rentrop score, BMI, TC, ApoB, lipoprotein a, fasting insulin, HOMA-IR,HOMA- beta and CRP are positively correlated to the formation of collateral circulation ( P ﹤ 0. 05 ); ApoA-Ⅰ and ISI were negatively correlated ( P ﹤0. 05 ) . Logistic regression analysis after calibration with weight, ApoA-Ⅰ and HOMA-beta factors, lipoprotein a ( OR 7. 575,P=0. 009), TC (OR 2. 154,P =0. 001) were found to be the independent factors of coronary collateral circulation formation. Conclusions TC, lipoprotein a, obesity, CRP, and HOMA-IR are correlated with the formation of coronary collateral circulation and may predict formation of collateral circulation in patients with CTO.
RESUMEN
Objective To study the location of coronary chronic total occlusion and the correlatin between coronary chronic total occlusion and coronary collateral. Methods SPSS was used to analyze the general clinical and coronary angiographic data of 113 patients with coronary bypass surgery performed. Results There were 61 patients with coronary chronic total occlusion. 71 sites of coronary chronic total occlusions were observed by coronary angiography, of which, one was located in left main coronary artery (0 9%), 17 in proximal left anterior descending artery (15 0%) , 9 in middle left anterior descending artery (8 0%), 3 in distal left anterior descending artery (2 7%), 5 in proximal left circumflex artery (4 4%), 6 in middle left circumflex artery (5 3%), 3 in distal left circumflex artery (2 7%), 9 in proximal right coronary artery (8 0% ), 10 in middle right coronary artery (8 8% ) and 8 in distal right coronary artery (7 1% ). There were 72 patients with coronary collateral. The coefficient of correlation between collateral and coronary chronic total occlusion was 0 707 (P=0 000 ).Conclusions Coronary chronic total occlusion is frequently located in proximal, middle left anterior descending artery and right coronary artery. There is significantly positive correlation between collateral and coronary chronic total occlusion.