Table 1

SYNTAX Protocol and ARC/ARC-Like Definitions of ST and GO

Stent ThrombosisGraft Occlusion
SYNTAX protocol definition
 The occurrence of any of the following:
  • 1. Clinical presentation of acute coronary syndrome with ST confirmed by angiography, multi-slice CT, or autopsy

    • a. Angiographic documentation of a complete occlusion (TIMI flow grade 0 or 1) of a previously successfully treated artery (TIMI flow gade 2 to 3 immediately after stent placement and diameter stenosis ≤30) and/or

    • b. Documentation by angiography, multi-slice CT, or autopsy of flow-limiting thrombus or complete luminal obstruction within or adjacent to a previously successfully treated lesion

  • 2. Q-wave MI in the territory of one or more of the treated vessels (LAD, LCX, RCA) within the first 30 days (acute or subacute)

SYNTAX protocol definition
 The occurrence of any of the following:
  • 1. Clinical presentation of acute coronary syndrome with GO confirmed by angiography, multi-slice CT, or autopsy

    • a. Angiographic documentation of occlusion (TIMI flow grade 0 or 1) of a vascular graft and/or

    • b. Documentation by angiography, multi-slice CT, or autopsy of flow-limiting thrombus or complete luminal obstruction within a bypass graft or a flow limiting thrombus adjacent to the anastomosis of previously bypassed coronary artery

  • 2. Q-wave MI in the territory of one or more of the treated vessels (LAD, LCX, RCA) within the first 30 days (acute or subacute)

ARC definite ST
  • 1. Angiographic or pathological confirmation of partial or total thrombotic occlusion within the peri-stent region and at least one of the following additional criteria:

    • a. Acute ischemic symptoms

    • b. Ischemic electrocardiographic changes

    • c. Elevated cardiac biomarkers

ARC-like definite GO
  • 1. SYNTAX protocol definition as stated in the preceding text

ARC probable ST
  • 1. Any unexplained death within 30 days of stent implantation

  • 2. Any MI that is related to documented acute ischemia in the territory of the implanted stent without angiographic confirmation of ST

ARC-like probable GO
  • 1. Any unexplained death within 30 days of graft

  • 2. Any MI that is related to documented acute ischemia in the territory of the anastomosed graft without angiographic confirmation of GO

ARC possible ST
  • 1. Any unexplained death beyond 30 days

ARC-like possible GO
  • 1. Any unexplained death beyond 30 days

ARC = Academic Research Consortium; CT = computed tomography; GO = graft occlusion; MI = myocardial infarction; LAD = left anterior descending artery; LCX = left circumflex artery; RCA = right coronary artery; ST = stent thrombosis; TIMI = Thrombolysis in Myocardial Infarction.

  • The definitions of protocol GO and ARC-like definite GO were identical.

  • Because subjects had left main or de novo 3-vessel disease, it was assumed that an MI in any of the 3-vessel territories for 3-vessel disease or the left coronary system for unprotected left main coronary artery disease without subsequent angiographic confirmation of graft patency was classified as probable GO.

  • ARC possible GO was identical to ARC-like possible ST.