Volume 206 - Issue 9
Coronary stent technology: a narrative review
Authors: Nigel Jepson and Daniel Chen
Med J Aust 2017; 206 (9): 413-414. || doi: 10.5694/mja16.01251
Published online: 15 May 2017
Published online: 15 May 2017
In reply
In reply:
We thank Skiba and Merry for their interest in our article.1 A discussion of the method of myocardial revascularisation was, however, outside the scope of the commissioned review.
While the role of coronary artery bypass grafting (CABG) surgery remains important, the assertion that “CABG remains the gold standard of treatment” despite the advent of second generation drug-eluting stents (DESs) requires further clarification.
Firstly, the SYNTAX trial2 enrolled stable patients with three-vessel coronary disease using an obsolete, first generation paclitaxel-eluting stent. It is unfortunate that newer generation DESs associated with significantly improved clinical outcomes1 have yet to be compared with CABG in appropriately powered randomised studies. Therefore, the current European Society of Cardiology and European Association for Cardio-Thoracic Surgery guidelines3 recommend CABG in stable and anatomically complex three-vessel disease, particularly in patients with diabetes. However, percutaneous coronary intervention (PCI) and CABG receive comparable recommendations in less complex multivessel disease, including left mainstem obstruction.
Secondly, the cited meta-analysis of PCI versus CABG4 is misleading. Only two of its six trials used first generation DESs, with bare metal stents in the remainder. The BEST trial,5 comparing the second generation everolimus-eluting DESs with CABG, was terminated prematurely due to slow enrolment, limiting its power to ascertain a difference. In addition, the higher rates of late spontaneous myocardial infarction and revascularisation with PCI were driven by suboptimal rates of complete revascularisation (49.1% v 28.5% in the CABG cohort).
Finally, surgical revascularisation based only on angiographic findings is unhelpful in directing clinical decision making in the presence of significant comorbidities, including advanced age.6 When life expectancy is significantly limited, long term survival advantages of CABG are not evident. Moreover, while unplanned revascularisation significantly favoured CABG over PCI in the SYNTAX trial (13.7% v 25.9%, P < 0.0001) at 5 years,2 the rate of stroke was significantly higher with CABG (2.2% v 0.6%, P = 0.003) at 12 months. Therefore, the clear advantages and trade-offs with the two strategies need to be discussed as part of an informed decision-making process.
PCI and CABG are complementary revascularisation strategies. Their comparison will soon be further informed by the highly anticipated results of appropriately powered pivotal trials comparing new generation DESs with “gold-standard CABG”.7
Competing interests
No relevant disclosures.
References
- Chen D, Jepson N. Coronary stent technology: a narrative review. Med J Aust 2016; 205: 277-281.
- Mohr FW, Morice MC, Kappetein AP, et al. Coronary artery bypass graft surgery versus percutaneous coronary intervention in patients with three-vessel disease and left main coronary disease: 5-year follow-up of the randomised, clinical SYNTAX trial. Lancet 2013; 381: 629-638.
- Windecker S, Kolh P, Alfonso F, et al. 2014 ESC/EACTS Guidelines on myocardial revascularization: the task force on myocardial revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS) developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI). Eur Heart J 2014; 35: 2541-2619.
- Sipahi I, Akay MH, Dagdelen S, et al. Coronary artery bypass grafting vs percutaneous coronary intervention and long-term mortality and morbidity in multivessel disease: meta-analysis of randomized clinical trials on the arterial grafting and stent era. JAMA Intern Med 2014; 174: 223-230.
- Park SJ, Ahn JM, Kim YH, et al. Trial of everolimus-eluting stents or bypass surgery for coronary disease. N Engl J Med 2015; 372: 1204-1212.
- Cockburn J, Hildick-Smith D, Trivedi U, de Belder A. Coronary revascularisation in the elderly. Heart 2017; 103: 316-324.
- Kappetein A, Serruys P, Sabik J, et al. Design and rationale for a randomised comparison of everolimus-eluting stents and coronary bypass graft surgery in selected patients with left main coronary disease: the EXCEL trial. Eurointervention 2016; 12: 861-872.