Impact of evolocumab on coronary physiology and microstructure in de-novo heart transplant recipients.
Karim, S. R., et al.J Heart Lung Transplant. 2026 Jan;45(1):26-36.
Aims
To test whether adding evolocumab to standard post–heart-transplant care (including statins) alters early cardiac allograft vasculopathy (CAV), assessed by invasive coronary physiology.
Interventions
Monthly evolocumab 420 mg subcutaneous vs placebo for 12 months, on top of standard post-transplant therapy (statins + immunosuppression).
Participants
75 De-novo heart transplant recipients
Outcomes
The coronary physiology outcomes were: Fractional Flow Reserve (FFR), Coronary Flow Reserve (CFR), Index of Microcirculatory Resistance (IMR), Microvascular Resistance Reserve (MRR). Optical Coherence Tomography (OCT) for anatomy/microstructure: mean lumen area, intima area, intimal thickness, and derived ratios (segmentation/matching described).
Follow-up
Baseline coronary angiography/physiology/OCT at 4–8 weeks, repeated at 12 months post-transplant.
CET Conclusions
This is a study within a multicentre, randomised, double-blind, placebo-controlled trial scrutinising specifically invasive coronary physiology post-transplant. Their results suggest after suggests that PCSK9 inhibition with evolocumab, despite effective LDL lowering reported in EVOLVD, it does not measurably improve invasive coronary physiology or OCT-derived coronary structure in the first year after de-novo heart transplantation. Between-group analysis showed no significant differences in 12-month change in either physiological or OCT-derived measures. This included FFR (Δ difference 0.001, p=0.42), CFR (Δ difference 0.59, p=0.69), IMR (Δ difference 0.76, p=0.09), MRR (Δ difference 0.19, p=0.70), OCT lumen area (Δ difference −1.37 mm², p=0.38), and OCT intima area (Δ difference 0.05 mm², p=0.88). However, when all patients were considered together, within-cohort analysis demonstrated structural progression over 12 months on OCT, with significant luminal narrowing and an increase in intimal area. In contrast, physiological indices remained broadly stable over the same period, suggesting that OCT was more sensitive in detecting early interval change. The design of the overarching trial is good, and the outcome measures here are relatively unbiased physiological assessments but is limited by the small sample size with the patients split some having OCT and others FFR/CRF/IMR. Other limitations were that while the coronary physiology is relatively unbiased, it is still procedural so there could be centre-to-centre variation, the 1-year follow-up maybe to short for the lipid-lowering benefits seen in the main trial to translate into improved cardiac physiology and statistically they have conducted multiple comparisons not prespecified in the design with no formal multiplicity correction Clinically, the findings support the idea that very-early CAV may be driven by non–lipid-dominant processes (ethrombotic/fibrotic remodeling signals), so LDL lowering alone may be insufficient as a strategy to prevent early intimal proliferation, though longer follow-up and larger studies are needed.
Trial registration
ClinicalTrials.gov - NCT03734211