A global research initiative will compare coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI) in patients with ischaemic left ventricular dysfunction, closing the gap for “modern, high-quality evidence” of the optimal treatment strategy in this patient cohort.
Attendees of the 2022 European Association of Cardio-Thoracic Surgery (EACTS) annual meeting (5–8 October, Milan Italy) were offered a glimpse of the direction of the Canadian CABG or PCI trial—STICH3C—part of a broader collective of international studies known as STICH 3.0, by investigator Stephen Fremes (Sunnybrook Research Institute, Toronto, Canada).
The original STICH trial, which began more than a decade ago, compared a strategy of CABG to medical therapy, reporting no difference between the two arms in the primary endpoint of all-cause mortality at five years, but a significant difference at ten years, favouring the surgical procedure. More recently, REVIVED BCIS-2 compared PCI to optimal medical therapy in patients with severe left ventricular dysfunction, reporting no difference between the two approaches in terms of all-cause mortality or heart failure hospitalisation—a result that drew surprise when it was first revealed at the at the annual congress of the European Society of Cardiology (ESC 2022; 26–29 August, Barcelona, Spain).
“I think that there is equipoise presently regarding the preferred modality of revascularisation in patients with ischaemic left ventricular systolic dysfunction that CABG is preferred in patients who are good surgical candidates,” Fremes commented in his presentation at the EACTS meeting. “PCI is a less invasive alternative to CABG, certainly with lower rates peri-procedurally, and [which] may retain some of the benefits long term.”
Fremes went on to outline the details of STICH3C trial, which has been granted funding by the Canadian Institutes of Health Research (CIHR). The trial’s primary aim is to determine whether CABG, compared to PCI is associated with a reduction in all-cause mortality, stroke, post-procedural myocardial infarction (MI), repeat revascularisation or heart failure readmission over a median follow-up of five years, in patients with multivessel or left main coronary artery disease and ischaemic left ventricular dysfunction.
The study is seeking to enrol 754 patients in at least 45 centres. STICH3C, Fremes noted, is part of the STICH 3.0 collaborative, an international consortium addressing similar trials.
“The aim of the collaborative is to conduct harmonised randomised controlled trials comparing PCI to CABG in similar patient populations with ischaemic left ventricular dysfunction,” Fremes detailed. “Each study [will be] addressing a unique question, each study receiving funding from a national agency, and the goal of that is to, later on, merge individual patient data and address mortality.”
Presently, the Canadian, Swedish and Danish studies have been approved funding from their relevant bodies, with studies in the UK, USA, The Netherlands and Australia also pursuing applications. An overall sample size of 3,000 would provide 90% power to test a “really important” difference in mortality, Fremes commented.