Large Study Finds DCBs Not as Effective as Newer-Generation DES
Despite small randomized trials suggesting comparable results in patients with small-vessel (≤2.5 mm) coronary artery disease (CAD), an analysis of 14,788 patients suggests that drug-coated balloons (DCBs) are associated with a significantly higher risk of restenosis (adjusted hazard ratio: 2.027) up to 3 years after percutaneous coronary intervention (PCI) than newer-generation drug-eluting stents (DES).
Angelo Silverio, MD, of Uppsala University, and colleagues used the Swedish Angiography and Angioplasty Registry (SCAAR) to conduct their study, which was published in JACC: Cardiovascular Interventions.
They reported no difference in definite target lesion thrombosis at 3-year follow-up, a co-primary outcome, nor in the occurrence of all-cause death or myocardial infarction, both secondary outcomes. Still, given the doubling in risk of restenosis at 3-year follow-up compared to newer-generation DES, the authors suggested that DCB use in small coronary vessels “should be limited to selected cases for which stenting is not a viable therapeutic option.”
There were reasons to think DCBs would be ideal for small-vessel CAD, including a potentially lower risk of stent thrombosis, shorter duration of dual antiplatelet therapy, lack of a permanent vascular “cage,” and ability to inhibit neointimal proliferation.
Early data were encouraging, but two previous randomized studies – PICCOLETO (n = 62) and BELLO (n = 182) – had much smaller sample sizes, selective enrollment only of patients with stable or unstable angina, a study design addressing short-term 6-month angiographic outcomes and old-generation DES.
That is in contrast with the data from SCAAR, which included a large population of unselected patients (including acute myocardial infarction), treated with DCB (n = 1,154) or newer-generation DES (n = 13,634), and reporting the occurrence of events during a wider time window (3 years).
By linking to other nationwide registries, the investigators were able to evaluate outcomes in all patients, ensuring a real-world, all-comer analysis. Nevertheless, in an accompanying editorial, Francesco Giannini, MD, of Maria Cecilia Hospital, Cotignola, Italy, and colleagues were not quite sure whether the results are “clearing the fog or adding to it.”
The issue is heterogeneity in the reported literature. Differences in definition of small vessels, implantation technique, use of pharmacological therapies, and outcomes evaluated vary significantly across the different trials and studies.
While the SCAAR investigators concluded that DCBs are “not an equally effective alternative to newer-generation DES for percutaneous treatment of small coronary vessels,” the editorial commentators await the results of future trials and studies such as BASKET-SMALL 2.
Moreover, they added, DCB technology will evolve as industry and operator experience grows.
A consensus on definitions would be helpful for future trials. And, they added, an alternative – and the oldest method to treat small vessel CAD – medical therapy, may have a role and could be considered in future studies.
Silverio A, Buccheria S, Venetsanos D, et al. Percutaneous Treatment and Outcomes of Small Coronary Vessels: A SCAAR Report. JACC Cardiovasc Interv 2020 Feb 12; [Epub ahead of print] http://interventions.onlinejacc.org/content/early/2020/02/05/j.jcin.2019.10.062
Gianninia F, Khokhara AA, Albanib S. Percutaneous Intervention in Small Vessel Coronary Disease. Time to Clear the Fog? JACC Cardiovasc Interv 2020 Feb 12; [Epub ahead of print] http://interventions.onlinejacc.org/content/early/2020/02/05/j.jcin.2019.11.011