BBC ONE: Simple, Complex Bifurcation Stenting Both Improve QoL
In patients with coronary bifurcation lesions, both simple and complex stenting strategies substantially improve quality of life (QoL), with a reduced need for antianginal drugs. The results, from a subanalysis of a large randomized trial, were published in the February 2013 issue of JACC: Cardiovascular Interventions.
For the BBC ONE (British Bifurcation Coronary; Old, New, and Evolving Strategies) trial, published in Circulation in 2010, David J. Hildick-Smith, MD, of Royal Sussex County Hospital (Brighton, United Kingdom), and colleagues randomized 500 patients with significant coronary bifurcation lesions requiring PCI to receive either a simple or complex stenting strategy with Taxus paclitaxel-eluting stents (Boston Scientific, Natick, MA). Based on intention to treat, the primary endpoint (a composite of death, MI, and TVF at 9 months) favored the simple over the complex strategy. The difference was driven by a reduction in MI (3.6% vs. 11.2%; P = 0.001).
As part of the original study protocol, patients were given the Seattle Angina Questionnaire (SAQ) at baseline and 9 months. Canadian Cardiovascular Society class and antianginal drug use also were evaluated.
Function Improves Irrespective of Strategy
For the subanalysis, the entire cohort showed improvement on 4 of the 5 SAQ scales, the exception being treatment satisfaction. There also was improvement in Canadian Cardiovascular Society class, from 5.3% of patients in class 0 at baseline to 64.0% at follow-up (P < 0.001). Similarly, at baseline the median number of antianginal agents was 2; this decreased to 1 at 9 months. There was also no difference between simple and complex groups in antianginal drug use at follow-up (P = 0.96).
No differences emerged between the simple and complex strategies for any of the SAQ scales. The researchers also conducted an analysis of change in individual patients’ scores on each SAQ scale and again found no disparities by stenting strategy. The percentage of patients free of angina at follow-up was 65.1% in the simple group and 59.7% in the complex group (P = 0.23).
The SAQ has 5 scales that measure different aspects of the potential functional impact of CAD: angina frequency, angina stability, physical limitation, treatment satisfaction, and disease perception.
Findings Counter ‘Pinched’ Sidebranch Debate
“The data shown here demonstrate that bifurcation stenting (irrespective of simple or complex strategy) is associated with a highly significant and sustained improvement in health-related functional status and quality of life,” the study authors write.
The findings appear to contradict the clinical advantage for the simple approach found by BBC ONE. But Dr. Hildick-Smith and colleagues note that the primary endpoint difference in the trial was driven in part by results of periprocedural enzyme testing (total creatine kinase ≥ 3 times the URL), which “are frequently associated with minimal symptoms and are often of debatable clinical relevance.”
Additionally, the study authors say the QoL data “counter the intuitive suggestion that a simple strategy leaving a ‘pinched’ side branch ostium creates a substrate for future symptoms related to ischemia in the side branch territory.”
However, they acknowledge that with longer follow-up it is possible that differences between the strategies may emerge. Both restenosis and stent thrombosis were numerically higher in the complex stenting group, though the differences were not significant. Another issue is that the exclusive use of Taxus stents might have been disadvantageous for the complex group since these devices “are known to have greater late lumen loss and in-stent restenosis (and stent thrombosis rates) than second-generation everolimus-eluting stents,” Dr. Hildick-Smith and colleagues write.
Nevertheless, they conclude that the lack of difference “strengthens the argument that a default simple strategy is preferable in most cases, given its other proven advantages (reduced procedural duration, radiation dose, equipment costs, and so on).”
Provisional Stenting as Default?
But in an editorial accompanying the study, Antonio Colombo, MD, of Centro Cuore Columbus (Milan, Italy), says several factors make such a strong conclusion difficult.
In addition to the need for longer follow-up, Dr. Colombo points out that the actual complexity of bifurcation lesions is not fully described. More than 80% of patients had ‘true bifurcation’ as per Medina classification but the metric does not incorporate the size of the side branch, extension of the lesion along the length of the side branch, or the degree of myocardial subtended. Therefore, more complex lesions were perhaps excluded, introducing selection bias, he suggests.
The DKCRUSH-II study, on the other hand, enrolled a similar patient population to BBC ONE but included side-branch lesions measuring a mean of 15 mm. That trial favored a 2-stent technique over provisional stenting, Dr. Colombo notes.
In an e-mail communication with TCTMD, Somjot S. Brar, MD, MPH, of Kaiser Permanente (Los Angeles, CA), said the BBC ONE data do provide some insight into the importance of the side branches. Even so, he concurred with the limitations expressed by Dr. Colombo, adding that it remains unknown if the results would be different with newer DES technology.
“For now, clinicians should take comfort in knowing that for many (but not all) patients, the provisional stenting strategy should be the default approach and is associated with quality of life improvement, comparable to that of the 2-stent strategy. It is also important to recognize that provisional stenting, while suitable for many patients, is not appropriate for all bifurcation lesions,” he said.
In a telephone interview with TCTMD, Samin K. Sharma, MD, of Mount Sinai Medical Center (New York, NY), agreed.
“This is a positive message because it tells us that when we treat bifurcation lesions, quality of life improves,” he said. “For people like myself, who are believers in the 2-stent strategy, it’s also a positive because although there were more periprocedural MIs with [that approach], at follow up quality of life [was just as high] and degree of angina was not higher with the complex strategy.”
The simple strategy involved planned stenting of the main vessel only, with provisional treatment of the side branch. The complex strategy involved planned main vessel and side branch stenting with culotte or crush technique.
- Sirker A, Sohal M, Oldroyd K, et al. The impact of coronary bifurcation stenting strategy on health-related functional status: A quality-of-life analysis from the BBC One (British Bifurcation Coronary; Old, New, and Evolving Strategies) study. J Am Coll Cardiol Intv. 2013;6:139-145.
- Colombo A, Basavarajaiah S. Can quality-of-life analysis aid in substantiating simple over complex strategies for bifurcation lesions? J Am Coll Cardiol Intv. 2013;6:146-148.
- Dr. Hildick-Smith reports serving on the advisory board of Boston Scientific.
- Dr. Colombo reports being a minor shareholder of Coppello.
- Dr. Brar reports no relevant conflicts of interest.
- Dr. Sharma reports serving on the speakers bureau for Abbott and Boston Scientific.