This study aims to evaluate procedural and clinical outcomes of acute coronay syndrome (ACS) patients with aneurysmatic culprit right coronary artery (RCA).

The investigators sought differences in procedural (slow-flow, no-reflow, distal embolisation,Thrombolysis in Myocardial Infarction final flow (TIMI) etc.) and in immediate and long-term clinical outcomes between several subgroups such as index vs staged percutaneous coronary intervention (PCI), premedication vs none, use of IIb/IIIa inhibitors vs none, bare metal stent (BMS) vs drug eluting stent (DES), ultrathin DES vs thick DES, durable polymer vs bioresorbable or free polymer etc.

The investigators also want to investigate the efficacy of different technical manoeuvres involved in resolving high thrombotic burden before stent deployment, such as thrombus aspiration, dilatation, intracoronary infusion of adenosine or thrombolytic agents, direct stenting etc.). Long-term follow-up includes target vessel failure (Cardiac Death, target vessel MI, clinically-driven target vessel revascularisation), define or probable stent thrombosis, target vessel revascularisation for ACS, clinically driven target vessel revascularisation and intrastent restenosis.

Inclusion Criteria:

• Patients with ACS of the aneurysmatic or ectasic RCA
• Patient with at least 6 months clinical or angiographic follow-up
• Patients with accurate procedural and clinical records (particularly use of drugs before, during and after procedure, according to RCA PCI procedure (index or staged).

Exclusion Criteria:

• Elective aneurysmatic or ectasic RCA PCI
• Patient with lack of accurate procedural and clinical data
• Patient with lack of clinical or angiographic follow up

Patients with aneurysmatic or ectatic right coronary artery disease in the acute setting following PCI.