Lower mortality, fewer amputations
The second study, published online Jan. 8, drew on health insurance claims in the German BARMER database to analyze 37,914 patients (mean age, 73.3 years, 49% female) and 21,546 propensity-score-matched patients with symptomatic CLTI or intermittent claudication (IC) with an index revascularization during 2010-2018 (Eur J Vasc Endovasc Surg. 2020 Jan 8. doi: 10.1016/j.ejvs.2019.12.034).
Patients were first stratified by CLTI or IC, and then by balloon vs. stent use. Paclitaxel-coated devices were then compared with uncoated devices within each stratum. The primary outcome was all-cause mortality at the end of follow-up.
From 2010 to 2018, the annual use of paclitaxel-coated devices increased dramatically from 3% to 39% in the CLTI group and from 4% to 48% in the IC group (P less than .001 for both).
A total of 2,454 deaths occurred within 5 years of follow-up (median, 2.7 years; longest, 8 years).
A Cox proportional hazards model (based on propensity-score-matched cohorts at 5 years) showed that, compared with uncoated devices, use of paclitaxel-coated devices in the CLTI group was associated with several improvements:
- Overall survival: HR, 0.83; 95% CI, 0.77-0.90.
- Amputation-free survival: HR, 0.85; 95% CI, 0.78-0.91.
- Major cardiovascular events: HR, 0.82; 95% CI, 0.77-0.88.
In the IC group, mortality was significantly better with DCB (HR, 0.87; 95% CI, 0.76-0.99) or a combination of DCB and drug-eluting stents (HR, 0.88; 95% CI, 0.80-0.98) than with uncoated devices, but similar for DES alone (HR, 0.91; 95% CI, 0.77-1.08).
No benefit was found for paclitaxel-coated devices in the IC group for AFS (HR, 0.91; 95% CI, 0.82-1.00) or major cardiovascular events (HR, 0.93; 95% CI, 0.87-1.00).
The authors acknowledge that “unmeasured confounding” may partly explain the results. It may be that patients revascularized with DCB or DES “are more likely to be treated in highly specialized trial centers with clear follow-up protocol.”
Moreover, these patients may have received “the best treatment,” including statin therapy, added Dr. Behrendt.
More evidence needed
Dr. Secemsky, who was not involved with either study, said the German investigators “did a wonderful job with this analysis in a large population of several thousand patients, showing nicely that after accounting for differences in comorbidities, the patients had no evidence of harm with [paclitaxel-coated] devices through 5 years.”
However, he cautioned, median follow-up time was just over 2 years. “Although the investigators had data all the way out to 5 years, over time, the number of patients contributing data became smaller, which results in more uncertainty with these longer-term findings,” he said. “As such, we still need to look at additional long-term data in this patient population to confirm the safety of these devices.”
At present, the “major consideration we want to address is whether it’s safe to use these devices, and we’re undertaking these analyses to examine safety, not to see if they improve mortality,” although the present study “has a suggestion of mortality benefit,” Dr. Secemsky said.
Dr. Katsanos added that paclitaxel-coated balloons “remain under investigation for below-knee arteries and critical limb ischemia,” with “a few randomized controlled trials on the way.”
“We need definitive evidence from high-quality multicenter controlled trials that these devices may improve wound healing and limb salvage without any systemic mortality risk,” he said.
Dr. Katsanos receives personal fees from Boston Scientific and Philips Healthcare. The study by Dr. Behrendt was part of the IDOMENEO project funded by the German Joint Federal Committee. Dr. Behrendt reports no relevant financial relationships. Dr. Secemsky reports institutional grants from Cook Medical, BD Bard, Medtronic, Beth Israel Deaconess Medical Center, and Boston Scientific, and reports consultancy for Cook Medical, BD Bard, and Medtronic.
This article first appeared on Medscape.com.