Predictors for Functionally Significant In-Stent Restenosis An Integrated Analysis Using Coronary Angiography, IVUS, and Myocardial Perfusion Imaging

OBJECTIVES The aim of this study was to assess the clinical and morphological predictors for functionally significant in-stent restenosis (ISR). BACKGROUND Although they have been studied de novo in native coronary artery lesions, the relationships between clinical and morphological characteristics and the hemodynamic significance of ISR are not well understood. METHODS In 175 patients with ISR of a single coronary artery (angiographic stenosis >50%), we compared quantitative coronary angiography and intravascular ultrasound (IVUS) with stress myocardial single-photon emission computed tomography (SPECT). A positive SPECT was a reversible perfusion defect in the territory of the ISR artery. RESULTS Overall, 103 (59%) patients had a positive SPEC. In-segment IVUS minimal lumen area (MLA) was significantly smaller in lesions with positive SPEC compared with negative SPECT (1.7 +/- 0.5 mm(2) vs. 2.4 +/- 0.8 mm(2), p < 0.001). Stent underexpansion (minimal stent area <5.0 mm(2)) was more common in the positive SPECT group than in the negative SPECT group (52% vs. 32%, p = 0.010). A positive SPECT was seen in 54% (65 of 121) of focal ISR lesions compared with 70% (38 of 54) of multifocal or diffuse ISR lesions as assessed by IVUS (p = 0.039). Independent determinants for a positive SPECT were diabetes (odds ratio [OR]: 2.41; 95% confidence interval [Cl]: 1.02 to 5.68; p = 0.046), in-segment angiographic diameter stenosis (OR: 1.06; 95% Cl: 1.03 to 1.09; p < 0.001), in-segment IVUS-MLA (OR: 0.30; 95% Cl: 0.14 to 0.63; p = 0.001), stent underexpansion (minimal stent area <5.0 mm(2)), (OR: 2.91; 95% Cl: 1.19 to 7.07; p = 0.019), proximal location of the IVUS-MLA (OR: 4.62; 95% Cl: 1.75 to 12.18; p = 0.002), and a multifocal or diffuse ISR pattern (OR: 2.50; 95% Cl: 0.99 to 6.28; p = 0.050). An in-segment angiographic diameter stenosis >= 69.5% (72% sensitivity, 74% specificity, area under the curve = 0.793) and an IVUS-MLA <= 1.9 mm(2) (67% sensitivity, 75% specificity, area under the curve = 0.756) best predicted a positive SPECT; however, the overall diagnostic accuracies were only 73% and 70%, respectively. CONCLUSIONS In lesions with ISR, neither angiography nor IVUS accurately predicted an abnormal SPECT. (C) 2013 by the American College of Cardiology Foundation