In a stunning revelation from the NEWTON-CABG CardioLink-5 study presented at the European Society of Cardiology Congress 2025, adding evolocumab (Repatha; Amgen) to statin therapy has proven ineffective in reducing the risk of saphenous vein graft (SVG) failure following coronary artery bypass grafting (CABG). This unexpected outcome highlights the ongoing challenges faced in cardiac surgery.

Lead investigator Dr. Subodh Verma from St. Michael’s Hospital in Toronto shared the disappointing statistics, stating, "Vein graft failure remains a stubborn issue, affecting 20-50% of grafts within two to four years post-surgery. This raises serious concerns about patient outcomes and long-term prognosis."

The study evaluated the impacts of LDL cholesterol levels on graft failure, but the results were alarming. Although previous research suggested that lower LDL levels could alleviate SVG occlusion, the NEWTON-CABG findings clearly indicate otherwise. Dr. Verma concluded, "Further cholesterol-lowering with PCSK9 inhibitors is not the solution. The LDL hypothesis is effectively debunked."

Conducted across 23 sites in Canada, the U.S., Australia, and Hungary, the trial involved 782 patients, aged around 66, who were split into groups receiving either evolocumab or a placebo alongside existing statin therapy. After 24 months, while the evolocumab group experienced a remarkable 52% reduction in LDL cholesterol, the rate of SVG disease was nearly identical between both groups, indicating no significant benefit from the treatment.

While the quest for effective interventions continues, the use of arterial grafts is being increasingly promoted. Evidence shows that arterial grafts, specifically internal thoracic arteries and radial arteries, yield better long-term results than SVGs. Yet, Dr. Verma acknowledges the practicality of SVGs in surgical procedures, pointing out, "Even with advancements in arterial grafting, the complete transition to arterial grafts is fraught with its own challenges."

Dr. François Mach from Geneva University Hospital added that this study isn’t a setback but rather a step forward, clarifying an important clinical dilemma. He noted the LDL reduction achieved by evolocumab aligns with prior landmark trials that did indicate benefits when combined with statin therapy for cardiovascular risks.

Despite the disappointment surrounding evolocumab's efficacy on graft failure, both experts concur the push for utilizing arterial grafts should be intensified, paving the way for potentially better patient outcomes in the future. The journey to fully understand SVG failures continues, prompting a critical reevaluation of current practices in cardiac bypass surgery.