Smart Angioplasty Research Team-Coronary CT Angiography Versus Standard Care as Follow-up Strategies in High-Risk Patients After PCI (SMART-CARE)

Inclusion Criteria: ① Patients aged 19 years old ② Patients who underwent successful PCI with one or more contemporary drug-eluting stents (stent diameter ≥3mm) or drug-coated balloons. ③ Patients must have at least one of the following criteria of complex coronary artery lesions or high-risk clinical characteristics: A. Complex coronary artery lesions: i. True bifurcation lesion (Medina 1,1,1/1,0,1/0,1,1) with side branch ≥2.5mm size ii. Chronic total occlusion (≥3 months) as target lesion iii. PCI for unprotected left main (LM) disease (LM ostium, body, distal LM bifurcation including non-true bifurcation) iv. Long coronary lesions (used stents or drug-coated balloons ≥38 mm in length) v. Multi-vessel PCI (≥2 major epicardial coronary arteries treated at one PCI session) vi. Multiple devices needed (≥3 more stents or drug-coated balloons per patient) vii. In-stent restenosis lesion as target lesion viii. Severely calcified lesion (encircling calcium in angiography) ix. Left anterior descending (LAD), left circumflex artery (LCX), and right coronary artery (RCA) ostial lesion B. High-risk clinical characteristics: i. Acute myocardial infarction (ST-elevation myocardial infarction \[MI\] or non-ST-elevation MI) with or without cardiogenic shock (SCAI Classification ≥C) at presentation ii. Diabetes mellitus which requires medical treatment (oral hypoglycemic agents or insulin) iii. End-stage renal disease under dialysis iv. Combined vascular disease other than coronary artery disease 1. Peripheral artery occlusive disease which is defined as A. Previous aorto-femoral bypass surgery, limb bypass surgery, or percutaneous transluminal angioplasty revascularization of the iliac, or infra-inguinal arteries, or B. Previous limb or foot amputation for arterial vascular disease, or C. History of intermittent claudication and one or more of the following: 1) An ankle/arm blood pressure (BP) ratio \< 0.90, or 2) Significant peripheral artery stenosis (≥50%) documented by angiography, or by duplex ultrasound, or D. Previous carotid revascularization or asymptomatic carotid artery stenosis ≥50% as diagnosed by duplex ultrasound or angiography. 2. Thoracoabdominal aortic disease which is defined as A. Documented thoracoabdominal aortic aneurysm by duplex ultrasound, angiography, or computed tomography angiography B. Previous endovascular or surgical treatment for thoracoabdominal aortic aneurysm ④ Subject who can verbally confirm understandings of risks, benefits and surveillance strategy alternatives of receiving CCTA and he/she or his/her legally authorized representative provides written informed consent prior to any study related procedure. Exclusion Criteria: ① Advanced chronic kidney disease (Creatinine clearance \<30 ml/min/1.73 m2) not on dialysis * Known true anaphylaxis to contrast medium (not allergic reaction but anaphylactic shock) * Pregnancy or breast feeding ④ Non-cardiac co-morbid conditions are present with life expectancy \<1 year or that may result in protocol non-compliance (per site investigator's medical judgment) ⑤ Unwillingness or inability to comply with the procedures described in this protocol.