Prognostic value of coronary computed tomography angiographic derived fractional flow reserve: a systematic review and meta-analysis.

OBJECTIVES

To obtain more powerful assessment of the prognostic value of fractional flow reserve testing we performed a systematic literature review and collaborative meta-analysis of studies that assessed clinical outcomes of CT-derived calculation of FFR (FFR) (HeartFlow) analysis in patients with stable coronary artery disease (CAD).

METHODS

We searched PubMed and Web of Science electronic databases for published studies that evaluated clinical outcomes following fractional flow reserve testing between 1 January 2010 and 31 December 2020. The primary endpoint was defined as 'all-cause mortality (ACM) or myocardial infarction (MI)' at 12-month follow-up. Exploratory analyses were performed using major adverse cardiovascular events (MACEs, ACM+MI+unplanned revascularisation), ACM, MI, spontaneous MI or unplanned (>3 months) revascularisation as the endpoint.

RESULTS

Five studies were identified including a total of 5460 patients eligible for meta-analyses. The primary endpoint occurred in 60 (1.1%) patients, 0.6% (13/2126) with FFR>0.80% and 1.4% (47/3334) with FFR ≤0.80 (relative risk (RR) 2.31 (95% CI 1.29 to 4.13), p=0.005). Likewise, MACE, MI, spontaneous MI or unplanned revascularisation occurred more frequently in patients with FFR ≤0.80 versus patients with FFR >0.80. Each 0.10-unit FFR reduction was associated with a greater risk of the primary endpoint (RR 1.67 (95% CI 1.47 to 1.87), p<0.001).

CONCLUSIONS

The 12-month outcomes in patients with stable CAD show low rates of events in those with a negative FFR result, and lower risk of an unfavourable outcome in patients with a negative test result compared with patients with a positive test result. Moreover, the FFR numerical value was inversely associated with outcomes.