Introduction:

Fractional flow reserve (FFR) remains the gold standard for functional evaluation in coronary artery disease (CAD). However, non-hyperemic indices, such as diastolic pressure ratio (dPR) and resting full-cycle ratio (RFR), are increasingly utilized in clinical practice. Data on the safety and long-term outcomes of deferred revascularization based on these indices remain limited.

Aim:

This study aimed to evaluate the safety of deferred revascularization in patients with CAD using dPR and RFR indices.

Material and methods:

Between January and June 2022, all consecutive patients undergoing functional coronary evaluations at a large tertiary hospital were screened. Primary endpoints included major adverse cardiovascular events (MACE), a composite of all-cause mortality, myocardial infarction (MI), and target vessel revascularization (TVR), along with individual endpoints at 1-year follow-up.

Results:

Of 321 patients evaluated, 290 met the eligibility criteria, and 204 underwent deferred revascularization based on non-hyperemic assessments. The cohort had a mean age of 68.2 years (SD ±8.9), with 76.8% male. Chronic coronary syndrome (57.2%), unstable angina (13.8%), and heart failure (9.3%) were the primary indications for coronary angiography. Among 230 lesions assessed with dPR and 243 with RFR, positive findings were observed in 17.4% and 13.2%, respectively (p = 0.15). At 1-year follow-up, MACE occurred in 7.8%, all-cause mortality was 4.9%, MI was 0.5%, and TVR was 2.5%.

Conclusions:

Deferred revascularization guided by dPR and RFR appears safe, with outcomes comparable to FFR-guided decisions in the literature. Larger randomized trials are needed to confirm these findings.