Angioplasty and Heart Stents to Treat Individuals With an Occluded Artery Following a Heart Attack (TOSCA-2)

The purpose of this study is to evaluate arterial patency and left ventricular ejection fraction by examining angiographic data one year following a heart attack and treatment with late revascularization.

BACKGROUND: The Occluded Artery Trial (OAT) is an international study with 3200 participants. Its goal is to determine if delayed mechanical reperfusion by means of percutaneous transluminal coronary angioplasty (PTCA) and stenting reduces death, heart attacks, and hospitalization in individuals with New York Heart Association (NYHA) Class IV heart failure and a persistently occluded infarct-related artery (IRA) 3 to 28 days following a heart attack. While left ventricular (LV) function improvement has been suggested as a benefit of late reperfusion, solid evidence to support this claim is lacking. Furthermore, while stenting has reduced reocclusion rates after total occlusion PTCA, the reocclusion rate after a recent heart attack is unknown. DESIGN NARRATIVE: This study is a substudy of OAT and will enroll 380 participants. The primary aims of the study include the following: 1) to compare long-term patency rates between the two treatment groups (conventional medical therapy or PTCA and stenting) by means of follow-up coronary angiography one year after enrollment; and 2) to compare the change in global LV ejection fraction between the two treatment groups utilizing baseline and follow-up contrast LV angiograms. Secondary aims include the following: 1) comparison of regional wall motion and LV volumes; 2) study of the effect of reocclusion and spontaneous recanalization on LV function; and 3) study of the effect of duration of occlusion on changes in LV function after Percutaneous Coronary Intervention (PCI). The substudy will be conducted at 21 OAT study sites. The Substudy Coordinating Center (SCC) is at the University of Alberta in Edmonton, Canada. The Data Coordinating Center (DCC) is at the Maryland Medical Research Institute, which is the DCC for the OAT study. The Angiographic Core Laboratory is at the University of British Columbia.

Inclusion Criteria: Has experienced a heart attack 3 to 28 days prior to study entry Has a persistently occluded IRA

Dzavik V, Buller CE, Lamas GA, Rankin JM, Mancini GB, Cantor WJ, Carere RJ, Ross JR, Atchison D, Forman S, Thomas B, Buszman P, Vozzi C, Glanz A, Cohen EA, Meciar P, Devlin G, Mascette A, Sopko G, Knatterud GL, Hochman JS; TOSCA-2 Investigators. Randomized trial of percutaneous coronary intervention for subacute infarct-related coronary artery occlusion to achieve long-term patency and improve ventricular function: the Total Occlusion Study of Canada (TOSCA)-2 trial. Circulation. 2006 Dec 5;114(23):2449-57. doi: 10.1161/CIRCULATIONAHA.106.669432. Epub 2006 Nov 14.

Steigen TK, Buller CE, Mancini GB, Jorapur V, Cantor WJ, Rankin JM, Thomas B, Webb JG, Kronsberg SS, Atchison DJ, Lamas GA, Hochman JS, Dzavik V. Myocardial perfusion grade after late infarct artery recanalization is associated with global and regional left ventricular function at one year: analysis from the Total Occlusion Study of Canada-2. Circ Cardiovasc Interv. 2010 Dec;3(6):549-55. doi: 10.1161/CIRCINTERVENTIONS.109.918722. Epub 2010 Nov 9.

Dzavik V, Buller CE, Devlin G, Carere RG, Mancini GB, Cantor WJ, Buszman PE, Rankin JM, Vozzi C, Ross JR, Forman S, Barton BA, Lamas AG, Hochman JS. Angiographic and clinical outcomes of drug-eluting versus bare metal stent deployment in the Occluded Artery Trial. Catheter Cardiovasc Interv. 2009 May 1;73(6):771-9. doi: 10.1002/ccd.21930.