Prognostic impact of angiographically morphology in functionally non-significant coronary stenosis
H Kirigaya, K Okada, S Kikuchi, H Nakahashi, K Matsushita, M Gohbara, N Iwahashi, K HibiAbstract
Background
While fractional flow reserve (FFR) plays a crucial role in determining initial management strategies for patients with intermediate coronary artery stenosis, adverse clinical events can still occur even in patients with negative FFR results, which remains scientifically noteworthy. We hypothesized that coronary angiographic findings may provide a certain answer to identify this unique patient subset.
Purpose
This retrospective study aimed to explore the prognostic values of angiographic morphology of functionally non-significant coronary stenosis.
Methods
A total of 209 intermediate lesions (percent stenosis of 50% to 75% on visual estimation) from 195 patients with FFR >0.80 and deferred revascularization were included in this analysis. Patients with a history of prior stent implantation and/or myocardial infarction were excluded. FFR were measured using a pressure wire in a standard manner. Based on coronary angiographic findings, target lesions were classified into focal lesions, defined as a single intermediate stenosis which lesion length of <20 mm, and tandem/diffuse lesions, defined as a sequential lesion with ≥2 focal lesions or a intermediate stenosis with lesion length of ≥20 mm. The angiographic contrast intensity (ACI) was also evaluated by calculating the ratio of mean pixel value of the target lesion site to that of the reference site (Figure). Higher ACI values indicate reduced contrast filling at the target lesion sites. Primary endpoint of this study was target-vessel failure (TVF).
Results
Median FFR value in the target lesions was 0.87 (interquartile range: 0.84 to 0.91). Patients (mean age was 71±9 years, 76% of patients were men) were followed for a median of 57 months. During this period, TVF occurred in 15 (7%) lesions. Patients with TVF, compared with those without, showed higher rates of diabetes mellitus (60% vs. 31%, p=0.026), dyslipidemia (87% vs. 52%, p=0.005), tandem/diffuse lesions (80% vs. 28%, p<0.001) and lesions with higher ACI (1.56±0.32 vs. 1.31±0.19, p=0.009). In the multivariate regression analysis, tandem/diffuse lesions and higher ACI were statistically associated with subsequent TVF (Table). Receiver operating characteristics curve analysis revealed the optimal cut-off value of ACI to predict TVF was 1.67. When stratified by tandem/diffuse lesions and ACI, subsequent TVF rates were markedly higher in lesions with both tandem/diffuse and ACI ≥1.67 compared with those without (75% vs. 1.5%, p<0.0001).
Conclusions
Tandem/diffuse intermediate lesions and higher angiographic contrast intensity were both associated with subsequent TVF in lesions with FFR negative. Although further studies need to elucidate the mechanisms of this association, our findings may suggest the need for close follow-up and targeted medical treatments for this patient subsets.figureFor image description, please refer to the figure legend and surrounding text.tableFor image description, please refer to the figure legend and surrounding text.