Coronary Plaque Characteristics Affect No-Reflow During Primary Percutaneous Coronary Intervention: A Pooled Analysis of 14 Observational Studies Using Intravascular Ultrasound.

The association between coronary plaque composition and no-reflow during percutaneous coronary intervention (PCI) is still debated. We performed a systematic literature search using MEDLINE, Embase, Cochrane, and Ovid databases for intravascular ultrasound (IVUS) studies evaluating the relationship between coronary plaque characteristics and no-reflow after PCI. Fourteen observational trials were included in the meta-analysis, including 1457 patients (237 in the no-reflow group, 1220 in the normal reflow group). Pooled analysis indicated that the no-reflow group had a significantly higher absolute volume of fibrofatty plaque (weighted mean differences [WMD], 4.94 mm(3); 95% confidence interval [CI], 1.83-l8.06; P =.002), external elastic membrane cross-sectional area (EEM-CSA) (WMD, 3.40 mm2; 95% CI, 2.22-4.58; P =.00001), plaque area (WMD, 4.06 mm(2); 95% CI, 2.24-5.89; P =.0001), and artery remodeling index (WMD, 0.09; 95% CI, 0.06-0.13; P =.00001), and a smaller percentage of fibrous plaque (WMD, -5.89 %; 95% CI, -0.66 to -11.12; P =.03) than in the normal reflow group. There were no significant differences in the other plaque components between the two groups. This meta-analysis confirmed that high absolute volume of fibrofatty plaque, EEM-CSA, plaque area, and coronary artery remodeling index, and a decreased percentage of fibrous plaque as detected by IVUS in culprit lesions, are linked with the development of the no-reflow phenomenon after PCI.