Clinical Effects of Physiologic Lesion Testing in Influencing Treatment Strategy for Multi-vessel Coronary Artery Disease
Authors: Rawal Harsh , Nguyen Tung D , Igbinomwanhia Efehi , Klein Lloyd W 
Published: May 2023

Introduction

Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) have become the standards for assessing physiological significance of intermediate-to-severe lesions on coronary angiography. However, the utilization of invasive physiology in patients with multi-vessel coronary artery disease (CAD) has not been definitively explored. The aim of this study is to examine how physiologic testing is applied to select treatment strategy in the clinic, and whether physiologic testing leads to differences in selection of treatment modality among patients presenting with two- and three-vessel CAD. The analysis identified how treatment strategy was decided based on FFR/iFR values in vessels selected clinically. Additionally, the differences in selection of treatment modality based on whether the vessel tested was the clinical target stenosis vessel was assessed.

Methods

In this series, 270 consecutive patients with angiographically determined multi-vessel disease who underwent FFR and/or iFR testing were included, and patients were classified initially based on their FFR/iFR results (normal or abnormal). Lesions were subsequently classified into target or non-target lesions based on clinical and non-invasive testing to identify if they were culprit lesions or not. Ordinal variables were analyzed using GraphPad Prism 8.4 (GraphPad Software). One-way ANOVA was used to determine if differences existed among the 3 subgroups prior to chi square testing. Chi-square goodness of fit test was used to determine if the treatment modality was chosen based on FFR/iFR values and lesion classification.

Results

FFR/iFR was abnormal in 51.9% of cases. Of the abnormal cases, 51.4% received coronary stenting (PCI) and 44.3% had bypass surgery (CABG). When the tested vessel was normal, CABG was least utilized. When the non-target vessel was tested, there was a substantial preference for PCI, however, when the target lesion was tested, all three treatments were used equally. In two-vessel CAD, the strategy depended on physiologic testing result of the target vessel. Medical therapy was preferred when the target vessel was normal, however, PCI was preferred if the target vessel was abnormal. In non-target vessel testing, PCI was preferred regardless of the physiologic testing result. The preferred treatment modality was substantially different in three-vessel CAD patients. Abnormal testing in target lesions was associated with significantly more CABG than medical therapy. PCI was preferred if the non-target vessel was tested. Furthermore, the incidence of tested lesions was significantly higher when located in the left anterior descending (LAD) when compared to other coronary arteries (e.g.left circumflex (LCX), right coronary artery (RCA)). In patients with two-vessel CAD, regardless of whether a target or non-target lesion was being tested, patients with LAD stenoses were more frequently treated by PCI.

Conclusion

The use of invasive physiologic testing in patients with multi-vessel CAD may alter the preferred treatment strategy. In clinical practice, this leads to a substantial increase in the use of PCI.