Prognostic value of age, creatinine, and left ventricular ejection fraction risk score in patients evaluated with fractional flow reserve: a cross-sectional study

SUMMARY OBJECTIVE: In this study, we investigated the relationship between age, creatinine, and left ventricular ejection fraction risk score and the severity of coronary lesions detected by applying fractional flow reserve in the patient group presenting with chronic coronary syndrome. Also, we presented long-term follow-up results in patients whose age, creatinine, and left ventricular ejection fraction score was evaluated by the fractional flow reserve procedure. METHODS: This study was planned retrospectively and in two centers. For this purpose, 114 patients who met the study criteria and who underwent elective fractional flow reserve between January 2014 and January 2019 were included in the study. Age, creatinine, and left ventricular ejection fraction was calculated as age/left ventricular ejection fraction +1 (if estimated glomerular filtration rate<30 mL/min). RESULTS: They were divided into two groups according to the cutoff value of the age, creatinine, and left ventricular ejection fraction score. A total of 76 patients had an age, creatinine, and left ventricular ejection fraction score of ≤1.17 (Group I) and 38 patients had an age, creatinine, and left ventricular ejection fraction score of >1.17 (Group II). The number of patients with severe lesions in fractional flow reserve was significantly higher in Group II compared with Group I (60.5 vs. 32.9%, p=0.005). According to the Kaplan-Meier analysis, a significant increase was observed in major adverse cardiac events and mortality during the follow-up period in the group with a high-risk score (Log Rank: 15.01, p<0.001 and Log Rank: 8.51, p=0.004, respectively). CONCLUSION: In light of the data we obtained from our study, we found a correlation between the severity of the lesion detected in fractional flow reserve and the age, creatinine, and left ventricular ejection fraction scores. In addition, we found that patients with high age, creatinine, and left ventricular ejection fraction scores had higher mortality and major adverse cardiac events rates during follow-up.

Performance Diagnóstica da FFR por Angiotomografia de Coronárias através de Software Baseado em Inteligência Artificial / Diagnostic Performance of a Machine Learning-Based CT-Derived FFR in Detecting Flow-Limiting Stenosis

Resumo Fundamento A quantificação não invasiva da reserva fracionada de fluxo miocárdico (FFR TC ) através de software baseado em inteligência artificial em versão mais atualizada e tomógrafo de última geração (384 cortes) apresenta elevada performance na detecção de isquemia coronariana. Objetivos Avaliar o desempenho diagnóstico da FFR TC na detecção de doença arterial coronariana (DAC) significativa em relação ao FFRi, em tomógrafos de gerações anteriores (128 e 256 cortes). Métodos Estudo retrospectivo com pacientes encaminhados à angiotomografia de artérias coronárias (TCC) e cateterismo (FFRi). Foram utilizados os tomógrafos Siemens Somatom Definition Flash (256 cortes) e AS+ (128 cortes). A FFR TC e a área luminal mínima (ALM) foram avaliadas em software (cFFR versão 3.0.0, Siemens Healthineers, Forchheim, Alemanha). DAC obstrutiva foi definida como TCC com redução luminal ≥50% e DAC funcionalmente obstrutiva como FFRi ≤0,8. Todos os valores de p reportados são bicaudais; e quando <0,05, foram considerados estatisticamente significativos. Resultados Noventa e três pacientes consecutivos (152 vasos) foram incluídos. Houve boa concordância entre FFR TC e FFRi, com mínima superestimação da FFR TC (viés: -0,02; limites de concordância: 0,14 a 0,09). Diferentes tomógrafos não modificaram a relação entre FFR TC e FFRi (p para interação = 0,73). A FFR TC demonstrou performance significativamente superior à classificação visual de estenose coronariana (AUC 0,93 vs. 0,61, p <0,001) e à ALM (AUC 0,93 vs. 0,75, p <0,001) reduzindo o número de casos falso-positivos. O melhor ponto de corte para a FFR TC utilizando um índice de Youden foi de 0,85 (sensiblidade, 87%; especificidade, 86%; VPP, 73%; NPV, 94%), com redução de falso-positivos. Conclusão FFR TC baseada em inteligência artificial, em tomógrafos de gerações anteriores (128 e 256 cortes), apresenta boa performance diagnóstica na detecção de DAC, podendo ser utilizada para reduzir procedimentos invasivos.

Abstract Background The non-invasive quantification of the fractional flow reserve (FFRCT) using a more recent version of an artificial intelligence-based software and latest generation CT scanner (384 slices) may show high performance to detect coronary ischemia. Objectives To evaluate the diagnostic performance of FFRCT for the detection of significant coronary artery disease (CAD) in contrast to invasive FFR (iFFR) using previous generation CT scanners (128 and 256- detector rows). Methods Retrospective study with patients referred to coronary artery CT angiography (CTA) and catheterization (iFFR) procedures. Siemens Somatom Definition Flash (256-detector rows) and AS+ (128-detector rows) CT scanners were used to acquire the images. The FFRCT and the minimal lumen area (MLA) were evaluated using a dedicated software (cFFR version 3.0.0, Siemens Healthineers, Forchheim, Germany). Obstructive CAD was defined as CTA lumen reduction ≥ 50%, and flow-limiting stenosis as iFFR ≤0.8. All reported P values are two-tailed, and when <0.05, they were considered statistically significant. Results Ninety-three consecutive patients (152 vessels) were included. There was good agreement between FFRCT and iFFR, with minimal FFRCT overestimation (bias: -0.02; limits of agreement:0.14-0.09). Different CT scanners did not modify the association between FFRCT and FFRi (p for interaction=0.73). The performance of FFRCT was significantly superior compared to the visual classification of coronary stenosis (AUC 0.93vs.0.61, p<0.001) and to MLA (AUC 0.93vs.0.75, p<0.001), reducing the number of false-positive cases. The optimal cut-off point for FFRCT using a Youden index was 0.85 (87% Sensitivity, 86% Specificity, 73% PPV, 94% NPV), with a reduction of false-positives. Conclusion Machine learning-based FFRCT using previous generation CT scanners (128 and 256-detector rows) shows good diagnostic performance for the detection of CAD, and can be used to reduce the number of invasive procedures.

Diagnostic performance of qfr for the evaluation of intermediate coronary artery stenosis confirmed by fractional flow reserve

Abstract Introduction: Quantitative flow ratio (QFR) is a novel method enabling efficient computation of FFR from three-dimensional quantitative coronary angiography (3D QCA) and thrombolysis in myocardial infarction (TIMI) frame counting. We decided to perform a systematic review and quantitative meta-analysis of the literature to determine the correlation between the diagnosis of functionally significant stenosis obtained by QFR versus FFR and to determine the diagnostic accuracy of QFR for intermediate coronary artery stenosis. Methods: We searched PubMed, Embase, and Web of Science for studies concerning the diagnostic performance of QFR. Our meta-analysis was performed using the DerSimonian and Laird random effects model to determine sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR). The sROC was used to determine diagnostic test accuracy. Results: Nine studies consisting of 1175 vessels in 1047 patients were included in our study. The pooled sensitivity, specificity, LR+, LR-, and DOR for QFR were 0.89 (95% CI: 0.86-0.92), 0.88 (95% CI: 0.86-0.91), 6.86 (95% CI,: 5.22-9.02), 0.14 (95% CI: 0.10-0.21), and 53.05 (95% CI: 29.75-94.58), respectively. The area under the summary receiver operating characteristic (sROC) curve for QFR was 0.94. Conclusion: QFR is a simple, useful, and noninvasive modality for diagnosis of functional significance of intermediate coronary artery stenosis.

Myocardial FFR (Fractional Flow Reserve) in patients with angiographically intermediate coronary artery stenosis - an initial institutional experience.

RESEARCH ARTICLE January-March 2013 | Volume 1 | Issue 1 | Page: 4-11 Myocardial FFR (Fractional Flow Reserve) in patients with angiographically intermediate coronary artery stenosis - an initial institutional experience Jagadish H. Ramaiah*, Raghu T. Ramegowda, Srinivas B. Chikkaswamy, Manjunath C. Nanjappa Sri Jayadeva Institute of Cardiovascular Sciences & Research, Jaya Nagar 9th Block, BG Road, Bangalore - 560069, Karnataka, INDIA Correspondence to: Dr. Jagadish H. Ramaiah, Email: jagadishhr@rediffmail.com Background: The clinical significance of coronary artery stenosis of intermediate severity can be difficult to determine. The management of intermediate coronary lesions, defined by a diameter stenosis of ≥40% to ≤70%, continues to be a therapeutic dilemma for cardiologists. The 2-dimensional representation of the arterial lesion provided by angiography is limited in distinguishing intermediate lesions that require stenting from those that simply need appropriate medical therapy. In the era of drug-eluting stents, some might propose that stenting all intermediate coronary lesions is an appropriate solution. However, the possibility of procedural complications such as coronary dissection, no reflow phenomenon, in-stent restenosis, and stent thrombosis requires accurate stratification of patients with intermediate coronary lesions to appropriate therapy. Myocardial fractional flow reserve (FFR) is an index of the functional severity of coronary stenosis that is calculated from pressure measurements made during coronary angiography. The objective of the study is to evaluate the usefulness of FFR in patients with angiographically intermediate coronary artery stenosis. Methods: 20 patients with intermediate coronary stenosis and chest pain of uncertain origin. The Exercise Electrocardiography (TMT), Myocardial Perfusion Imaging study (MPI), Quantitative Coronary Angiography (QCA) were compared with the results of FFR measurements. Results: 20 patients were undergone FFR measurement during the study period. With the mean age of 57.25±11.2 and male patients were 16 (80%), female patients 4 (20%), in all 13 patients with an FFR of <0.75, reversible myocardial ischemia was demonstrated unequivocally on at least one noninvasive test. In contrast, 5 of 7 patients with an FFR of >0.75 tested negative for reversible myocardial ischemia on TMT and MPI study. No revascularization procedures were performed in 7 (35%) patients, and no adverse cardiovascular events were noted in all these patients during 6 months of follow-up. Conclusions: In patients with coronary stenosis of intermediate severity, FFR appears to be a useful index of the functional severity of the stenosis and the need for coronary revascularization

Comparison between Fractinal Flow Reserve and Intravascular Ultrasound for Evaluation of Optimal Coronary Angioplasty

BACKGROUND: Intravascular ultrasound (IVUS) is one of the golden standards for the assessment of optimal angioplasty. Pressure-derived myocardial fractional flow reserve (FFRmyo) is a lesion-specific functional index of epicardial conduit and may be particularly useful for the assessment of optimal coronary angioplasty. The purpose of this study was to assess IVUS parameters and FFRmyo after successful angioplasty on coronary angiogram and compare them between balloon and stent group. METHODS: The study population consisted of 28 patients who underwent revascularization (14 cases of balloon angioplasty only, 14 cases of angioplasty with stent) from Jan. 1999 to Aug. 2000 at Inha University Hospital. After successful angioplasty on coronary angiogram, we measured minimal luminal diameter (MLD), minimal luminal area (MLA), lesion area stenosis (l-AST) and reference area stenosis (r-AST) with IVUS imaging. And we calculated FFRmyo from the ratio of mean coronary pressure distal to the stenosis (Pd) to the aortic mean pressure (Pa) during maximum coronary hyperemia (Pd/Pa). RESULTS: There was significant difference of MLD (2.2+/-0.4 vs 2.6+/-0.3), MLA (4.4+/-1.1 vs 6.4+/-1.7), r-AST (43.7+/-9.2 vs 29.8+/-9.4) and FFRmyo (0.89+/-0.07 vs 0.93+/-0.03) between balloon and stent group. All IVUS parameters (MLD, MLA, r-AST) are well correlated with FFRmyo after angioplasty (r=0.52, p<0.05, r=0.48, p<0.05 and r=-0.72, p<0.05 respectively). By multiple regression analysis, r-AST showed the best correlation with FFRmyo among IVUS parameters. CONCLUSION: Coronary angioplasty with stent showed more favorable MLD, MLA, r-AST and FFRmyo than balloon angioplasty. FFRmyo may be seemed to be alternative to IVUS for estimating the result of coronary angioplasty.