Current BVS inferior compared to contemporary DES, may require reintervention: BMJ

UK: An original investigation published in the BMJ Open Heart Journal, has mentioned that  BVS (current) are inferior to DES (contemporary) throughout the first five years at a minimum as shown is meta-analysis.

The main purpose of Bioresorbable vascular scaffolds (BVS) is to reduce the adverse events which are observed in conventional drug-eluting stents (DES) by dissolving once lasting patency is restored.

In DES, polymeric coatings are used to deliver an immunosuppressant, like, for example, Everolimus. This immunosuppressant inhibits neointimal hyperplasia, and restenosis is reduced. There is a reduced rate of repeat MI (myocardial infarction).

With the course of development, despite maturity reach and design to achieve long-term clinical trials, contemporary DES is still associated with problems. The metallic stent and polymeric coating cause inflammation leading to neoatherosclerosis, restenosis and late stent thrombosis. These factors are a risk to life.

BVS is a potential solution to this problem. The support provided by BVS is adequate to target the artery. It negates the complications also. The most extensively studied BVS is Abbott Vascular's Absorb BVS; this first gained regulatory approval.

The literature mentions that Absorb BVS group increases early stent/scaffold thrombosis (ST). A study comparing BVS and DES confirmed that BVS increased the risk of adverse safety and efficacy outcomes over the first two years.

Considering the above background, a study was conducted to compare the safety and efficacy of BVS versus conventional DES in managing coronary artery disease by PCI (percutaneous coronary intervention) using data published based on clinical outcomes from RCTs. The lead researcher was Elliot Jackson – Smith from the Warwick Medical School, UK.

The key points of the study are:

• The database searched were MEDLINE, EMBASE and Web of Science.

• Stent/scaffold thrombosis was the primary safety outcome.

• Target lesion failure (TLF) was the primary efficacy outcome.

• TLF included cardiac death, target vessel MI and ischaemia-driven target lesion revascularisation (ID-TLR).

• Combining all-death, all-MI and all-revascularisation were the secondary outcomes.

• RevMan V.5.4 was used to perform meta–analysis.

• A total of 11 919 patients were randomised.

• Six thousand four hundred thirty-eight patients were in BVS and 5481 in DES in 17 trials.

• There was a higher risk of ST in BVS, with a peak at two years, having an RR of 3.47 and a p-value of 0.0002.

• There was an increased risk of TLF in BVS, which peaked at three years.The RR was 1.35, and the p-value was 0.01, resulting from TVMI and ID-TLR. (higher rates).

• There were non-significant improvements after device dissolution in a follow-up of 5-year.

• All other outcomes were statistically equivalent.

• Applicability to all BVS is limited.

• 91% of the BVS that was studied was receiving Abbott's Absorb.

The researchers concluded that BVS (current) is inferior to DES (contemporary). This inferiority was throughout a minimum of 5 years. This increased the patient's risk of counteracting serious adverse events like ST and MI. This required reintervention of the target lesion.

The researchers summarised that BVS are inferior to DES in terms of safety. There is a significantly increased risk of ST. The risk is 3.47-fold greater at two years, and it begins early at the first 30 days and remains durable throughout five years of follow-up. This is interpreted as a 2.99-fold greater risk over 5 years. The risk of TLF is increased, 1.18-fold higher at five years and is related to elevated rates of TVMI and ID-TLR.

The researchers also said that, we know that BSV was designed to replace DES. We did a meta-analysis of 17 RCTs and compared BVS to DES. We have shown that BVS are inferior in safety and efficacy for up to 5 years. An elevated stent thrombosis rate drives this. We have built early research and are the first to compare RCTs of BVS to DES. We warrant further investigations to determine the possibility of deriving late benefits from the current BVS, they wrote.

Further reading:

Jackson-Smith E, Zioupos S, Banerjee P Bioresorbable vascular scaffolds versus conventional drug-eluting stents across time: a meta-analysis of randomised controlled trials. Open Heart 2022;9:e002107. doi: 10.1136/openhrt-2022-002107