CT-FFR-guided Strategy for In-stent Restenosis

Inclusion Criteria: * (1) \>18 years old; * (2) ability to provide informed consent; * (3) previous PCI who underwent CCTA and have at least 1 lesion with a percent diameter in-stent stenosis between 30% and 90% in a coronary artery with a ≥2.25 mm reference vessel diameter by visual assessment; * (4) accepted further clinically indicated coronary testing, coronary arteriography, or FFR, or IVUS, or PCI, etc. Exclusion Criteria: * (1) Prior coronary artery bypass surgery (CABG), heart valve surgery, cardiac pacemaker, or implanted cardiac defibrillator; * (2) Target vascular stents were evaluated for implantation within one month; * (3) unstable clinical conditions including acute chest pain, cardiogenic shock, congestive heart failure (NYHA grade III or IV), unstable blood pressure (systolic blood pressure \< 90mmHg) or acute pulmonary edema; * (4) Acute myocardial infarction occurred within 7 days before enrollment, and left ventricular ejection fraction ≤40%; * (5) Other severe cases are not suitable for clinical trials including complex congenital heart disease, sick sinus syndrome, long QT syndrome, severe arrhythmia, tachycardia, severe asthma, severe or very severe chronic obstructive pulmonary disease (COPD) and severe chronic renal damage; * (6) Contraindication to beta blockers, nitroglycerin, adenosine, or allergy to iodine contrast agents; * (7) Pregnancy or pregnancy status unknown; * (8) Life expectancy \<1 years; * (9)Repeated enrollment; * (10) Any other factors that other researchers consider not suitable for inclusion or completion of this study.