Delaying Revascularization Based on Fractional Flow Reserve Seems Effective

By Reuters Staff

January 13, 2020

NEW YORK (Reuters Health) - Delaying revascularization for up to two years based on fractional flow reserve (FFR) seems both safe and appropriate in real-world practice, according to researchers in Japan.

Current guidelines recommend FFR measurement before revascularization in patients with coronary artery stenosis unless there is objective evidence of ischemia, Dr. Shoichi Kuramitsu of Kokura Memorial Hospital, in Kitakyushu, and colleagues note in Circulation: Cardiovascular Interventions.

The aim, they say, is to reduce unnecessary revascularization and myocardial infarction. Although clinical trials have established the safety of the approach, there is little prospective large-scale data regarding real-world outcomes beyond one year.

To investigate, the researchers examined registry data from 28 Japanese centers. This involved 1,263 prospectively enrolled patients with 1,447 lesions in whom revascularization was deferred based on FFR.

The population, the researchers point out, predominantly consisted of asymptomatic or mildly symptomatic patients with stable coronary artery disease. The mean FFR was 0.86 with most lesions having an FFR greater than 0.80.

The cumulative two-year incidence of target-vessel failure (TVF) was 5.5% in deferred lesions, mainly brought about by a high rate (5.2%) of clinically driven target-vessel revascularization (CDTVR). The incidence significantly increased with decreasing FFR, particularly in the proximal location.

During follow-up, the two-year incidence of cardiac death was 0.41% and that of target-vessel related myocardial infarction was also 0.41%.

Data from other sources have shown an event rate "from 4.0% to 7.0% per year for a stented lesion, regardless of whether the lesion was functionally significant or not," according to the authors.

Performing percutaneous coronary intervention for nonischemic lesions, they add, "does not relieve any symptoms, exposing the patient to additional stent related risks."

Among independent predictors of two-year TVF was FFR value, with a hazard ratio of 1.07 per 0.01 decrease, a left-main-coronary-artery lesion (HR, 5.89) and a moderately to severely calcified lesion (HR, 2.49). Others were hemodialysis and having a right-coronary-artery lesion.

The researchers concede that the study "did not include patients who underwent revascularization according to FFR results, leading to the undetermined threshold value of FFR for revascularization decision making."

Nevertheless, they conclude that the findings complement those of previous randomized trials and demonstrate the safety of the FFR-based approach in daily clinical practice.

Dr. Kuramitsu did not respond to requests for comments.

SOURCE: Circulation: Cardiovascular Interventions, online December 30, 2019.