Deferred revascularization in diabetic patient according to combined invasive functional and intravascular imaging data: A case report.

BACKGROUND: Invasive functional evaluation by fractional flow reserve (FFR) is considered as a gold standard for the evaluation of intermediate coronary stenosis. However, in patients with diabetes due to accelerated progression of atherosclerosis the outcome may be worse even in the presence of negative functional testing. CASE SUMMARY: We present a case of 55-year-old male diabetic patient who was admitted for chest pain. Diagnostic coronary angiography disclosed 2 intermediate stenoses of the obtuse marginal branch with no evidence of restenosis on previously implanted stent. Patient undergone invasive functional testing of intermediate lesion with preserved FFR (0.88), low coronary flow reserve (1.2) and very high index of microvascular resistance (84). Due to discrepancy in invasive functional parameters, intravascular imaging with optical coherence tomography showed fibrotic stenoses without signs of thin-sup fibroatheroma. Because of the preserved FFR and no signs of vulnerable plaque, the interventional procedure was deferred and the patient continued with optimal medications. CONCLUSION: Combined functional and anatomic imaging of intermediate coronary stenosis in diabetic patients represent comprehensive contemporary decision pathway in the management of the patients.

Prognostic Value of Multiple Complete Blood Count-Derived Indices in Intermediate Coronary Lesions.

Complete blood count (CBC)-derived indices have been proposed as reliable inflammatory biomarkers to predict outcomes in the context of coronary artery disease. These indices have yet to be thoroughly validated in patients with intermediate coronary stenosis. Our study included 1527 patients only with intermediate coronary stenosis. The examined variables were neutrophil-lymphocyte ratio (NLR), derived NLR, monocyte-lymphocyte ratio (MLR), platelet-lymphocyte ratio (PLR), systemic immune inflammation index (SII), system inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI). The primary endpoint was the composite of major adverse cardiovascular events (MACEs), including all-cause death, non-fatal myocardial infarction, and unplanned revascularization. Over a follow-up of 6.11 (5.73-6.55) years, MACEs occurred in 189 patients. Receiver operator characteristic curve analysis showed that SIRI outperformed other indices with the most significant area under the curve. In the multivariable analysis, SIRI (hazard ratio [HR] 1.588, 95% confidence interval [CI] 1.138-2.212) and AISI (HR 1.673, 95% CI 1.217-2.300) were the most important prognostic factors among all the indices. The discrimination ability of each index was strengthened in patients with less burden of modifiable cardiovascular risk factors. SIRI also exhibited the best incremental value beyond the traditional cardiovascular risk model.

Prognostic value of myocardial flow reserve derived by quantitative SPECT for patients with intermediate coronary stenoses.

BACKGROUND: Functional assessment of myocardial ischemia is critical for patients with intermediate coronary stenosis. As the diagnosis performance of absolute quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) by single-photon emission tomography (SPECT) has been proven, its prognostic value in patients with intermediate coronary stenosis remains to be evaluated. METHODS: Patients with one or more target lesions of ≥ 50% to ≤ 80% diameter stenoses on invasive coronary angiography were prospectively included in this study. All patients were scheduled for clinically indicated SPECT myocardial perfusion imaging (MPI) within 3 months and agreed to provide informed consent to participate in quantitative SPECT acquisitions to obtain MBF and MFR values. The primary endpoint was defined as a composite of the major adverse cardiac events (MACE): Cardiac death, myocardial infarction, late revascularization and heart failure or unstable angina-related rehospitalization. RESULTS: One hundred and nineteen patients (mean age 57 ± 8 years, 62.2% men) were included in the analysis. The average lumen stenosis of patients was 67.0 ± 10.4%. Over a median follow-up duration of 1408 days (interquartile range 1297-1666 days), 18 patients (15.1%) had MACE. Patients with impaired MFR (MFR < 2) had a significantly higher incidence of events than those with preserved MFR (MFR ≥ 2) in Kaplan-Meier survival analysis (Log-rank = 8.105, P = 0.004), while no significant difference was found between patients with normal relative perfusion and those with relative perfusion abnormalities (log-rank = 0.098, P > 0.05). In a multivariate Cox hazards analysis, the SPECT-derived MFR remained an independent predictor of MACE (HR 0.352, 95% CI 0.145-0.854, P = 0.021). CONCLUSIONS: In a cohort of patients with angiographic intermediate coronary lesions, SPECT-derived MFR was an independent predictor of prognosis.

Long-term outcomes of intermediate coronary stenosis in patients undergoing hemodialysis after deferred revascularization based on fractional flow reserve.

OBJECTIVES: This study aimed to assess the long-term outcomes of patients undergoing hemodialysis (HD) after deferred revascularization based on fractional flow reserve (FFR). BACKGROUND: FFR is a practical technique for assessing the functional severity of intermediate coronary stenosis. Prior research has revealed a satisfactory outcome in patients after the deferral of percutaneous coronary intervention for coronary lesions based on FFR measurement. However, little research has been conducted focusing on patients undergoing HD. METHODS: The retrospective study comprised 225 consecutive patients with FFR assessment and deferred revascularization between January 2016 and December 2019. Based on a deferral cutoff FFR value of >0.80, we assessed the differences in all-cause death, major adverse cardiac events (MACEs), and target vessel failure (TVF) between the HD (n = 69) and non-HD groups (n = 156) during a mean ± standard deviation routine follow-up of 32.2 ± 13.4 months. RESULTS: Although the HD group had significantly higher rates of diabetes mellitus than the non-HD group (53.6% vs. 37.2%, p = 0.021), there were no significant differences in sex, left ventricular ejection fraction, or other risk factors between the groups, nor with respect to stenosis diameter or mean FFR. The HD group had a significantly higher incidence of TVF than the non-HD group (34.8% vs. 14.1%, p < 0.001), as well as a significantly higher risk of all-cause death and MACEs. CONCLUSIONS: The study revealed that deferred revascularization in coronary lesions with an FFR value of >0.80 in patients undergoing HD was associated with poor outcomes. Therefore, it is important to carefully monitor patients with intermediate coronary stenosis undergoing HD.

Serial changes in the quantitative flow ratio in patients with intermediate residual stenosis after percutaneous coronary intervention.

A beneficial surrogate marker for evaluating the effect of medical therapy is warranted to avoid deferred lesion revascularization. Similar to coronary artery imaging for monitoring the effects of medical therapy by analyzing plaque regression and stabilization, we hypothesized that evaluation of serial changes in the quantitative flow ratio (QFR) would serve as a surrogate marker of the effects of medical therapy against deferred lesion revascularization. Here, we investigated serial changes in QFR over time after percutaneous coronary intervention in patients who underwent medical therapy as a secondary prevention. Patients with intermediate stenosis in an untreated vessel observed at the baseline (BL) coronary angiography and follow-up (FU) coronary angiography performed 6-18 months after BL angiography were screened in 2 centers. A total of 52 patients were able to analyze both BL and FU QFR. The median QFR was 0.83 (IQR, 0.69, 0.89) at BL and 0.80 (IQR, 0.70, 0.86) at FU. The number of positive ΔQFR and negative ΔQFR were 21 and 31, respectively. The median ΔQFR was 0.05 (IQR, 0.03, 0.09) in positive ΔQFR and - 0.05 (IQR, - 0.07, - 0.03) in negative ΔQFR (p < 0.0001). Univariate and multivariate analyses revealed that LDL-C at FU predicted improvement in the QFR (OR 0.95, 95% confidence interval [0.91, 0.98], P = 0.001). Assessment of serial changes in the QFR may serve as a surrogate marker for the effects of medical therapy in patients with residual intermediate coronary stenosis.

Features of cardiopulmonary exercise test in patients with intermediate coronary stenosis / 中国康复理论与实践

ObjectiveTo review the clinical characteristics and capacity of cardiopulmonary exercise test in patients with intermediate coronary stenosis. MethodsFrom January, 2015 to January, 2020, the patients underwent coronary angiography and cardiopulmonary exercise test in Beijing Bo'ai Hospital were divided into intermediate coronary stenosis group (n = 184) and non-coronary heart disease group (n = 73). Symptoms, general information, laboratory and echocardiography information, results of cardiopulmonary exercise test were compared between two groups, and the main cardiovascular events during a year were observed. ResultsThe proportion of male (χ2 = 15.857, P < 0.001), smoking history (χ2 = 9.067, P = 0.003), hypertension history (χ2 = 15.087, P < 0.001) and hyperlipidemia history (χ2 = 13.507, P < 0.001) were more, and the level of hemoglobin A1c (Z = 2.431, P = 0.015) and high sensitivity C-reactive protein (Z = 2.108, P = 0.035) were higher in the intermediate coronary stenosis group, while less of them could reach anaerobic threshold (χ2 = 10.702, P = 0.001). The heard rate and respiratory exchange rate as anaerobic threshold decreased in the intermediate coronary stenosis group (Z > 2.156, P < 0.05). There was no significant difference in main cardiovascular events between the two groups within a year (P = 1.000). ConclusionCardiopulmonary capacity has been impaired in patients with intermediate coronary stenosis, who need to pay attention to the risk factors such as smoking, diabetes mellitus, hypertension and hyperlipidemia.

Comparison Between 5- and 1-Year Outcomes Using Cutoff Values of Pressure Drop Coefficient and Fractional Flow Reserve for Diagnosing Coronary Artery Diseases.

BACKGROUND: The current pressure-based coronary diagnostic index, fractional flow reserve (FFR), has a limited efficacy in the presence of microvascular disease (MVD). To overcome the limitations of FFR, the objective is to assess the recently introduced pressure drop coefficient (CDP), a fundamental fluid dynamics-based combined pressure-flow index. METHODS: We hypothesize that CDP will result in improved clinical outcomes in comparison to FFR. To test the hypothesis, chi-square test was performed to compare the percent major adverse cardiac events (%MACE) at 5 years between (a) FFR < 0.75 and CDP > 27.9 and (b) FFR < 0.80 and CDP > 25.4 groups using a prospective cohort study. Furthermore, Kaplan-Meier survival curves were compared between the FFR and CDP groups. The results were considered statistically significant for p < 0.05. The outcomes of the CDP arm were presumptive as clinical decision was solely based on the FFR. RESULTS: For the complete patient group, the %MACE in the CDP > 27.9 group (10 out of 35, 29%) was lower in comparison to the FFR < 0.75 group (11 out of 20, 55%), and the difference was near significant (p = 0.05). The survival analysis showed a significantly higher survival rate (p = 0.01) in the CDP > 27.9 group (n = 35) when compared to the FFR < 0.75 group (n = 20). The results remained similar for the FFR = 0.80 cutoff. The comparison of the 5-year MACE outcomes with the 1-year outcomes for the complete patient group showed similar trends, with a higher statistical significance for a longer follow-up period of 5 years. CONCLUSION: Based on the MACE and survival analysis outcomes, CDP could possibly be an alternate diagnostic index for decision-making in the cardiac catheterization laboratory. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov, identifier NCT01719016.

An old friend: uric acid and its association with fractional flow reserve

Background/aim: The aim of this study was to investigate the importance of preprocedural uric acid (UA) level in predicting fractional flow reserve (FFR) results of intermediate coronary lesions in patients with stable coronary artery disease undergoing coronary angiography. Materials and methods: We retrospectively analyzed 293 patients who underwent FFR measurement to determine the significance of intermediate coronary stenosis detected by conventional coronary angiography. Patients were divided into 2 groups: Group 1 (n = 127) included patients with FFR of <0.80 (hemodynamically significant lesions), and Group 2 (n = 169) consisted of patients with FFR of >0.80 (hemodynamically nonsignificant lesions). Uric acid levels were assessed in both groups with the enzymatic colorimetric method by clinical chemistry autoanalyzer. Results: The mean UA level was significantly higher in patients whose FFR indicated hemodynamically significant coronary lesions (UA: 5.43 ± 1.29 mg/dL in Group 1 vs. 4.51 ± 1.34 mg/dL in Group 2, P < 0.001). Conclusion: Elevated UA levels are associated with hemodynamically significant coronary lesions measured with FFR. Uric acid may be used as a predictor of hemodynamically compromised coronary lesions before FFR procedures.

Comparison of resting and adenosine-free pressure indices with adenosine-induced hyperemic fractional flow reserve in intermediate coronary lesions.

OBJECTIVE: Fractional flow reserve (FFR) using adenosine has been the gold standard in the functional assessment of intermediate coronary stenoses in the catheterization laboratory. We aim to study the correlation of adenosine-free indices such as whole cycle Pd/Pa [the ratio of mean distal coronary pressure (Pd) to the mean pressure observed in the aorta (Pa)], instantaneous wave-free ratio (iFR), and contrast-induced submaximal hyperemia (cFFR) with FFR. METHODS: This multicenter, prospective, observational study included patients with stable angina or acute coronary syndrome (>48 h since onset) with discrete intermediate coronary lesions (40-70% diameter stenosis). All patients underwent assessment of whole cycle Pd/Pa, iFR, cFFR, and FFR. We then evaluated the correlation of these indices with FFR and assessed the diagnostic efficiencies of them against FFR ≤0.80. RESULTS: Of the 103 patients from three different centers, 83 lesions were included for analysis. The correlation coefficient (r value) of whole cycle Pd/Pa, iFR, and cFFR in relation to FFR were +0.84, +0.77, and +0.70 (all p values < 0.001), respectively, and the c-statistic against FFR ≤0.80 were 0.92 (0.86-0.98), 0.89(0.81-0.97), and 0.91 (0.85-0.97) (all p values < 0.001), respectively. The best cut-off values identified by receiver-operator characteristic curve for whole cycle Pd/Pa, iFR, and cFFR were 0.94, 0.90, and 0.88, respectively, for an FFR ≤0.80. By the concept of "adenosine-free zone" (iFR = 0.86-0.93), 59% lesions in this study would not require adenosine. CONCLUSION: All the three adenosine-free indices had good correlation with FFR. There is no difference in the diagnostic accuracies among the indices in functional evaluation of discrete intermediate coronary stenoses. However, further validation is needed before adoption of adenosine-free pressure parameters into clinical practice.

Diagnostic efficacy of fractional flow reserve with coronary angiography in dual-source computed tomography scanner.

OBJECTIVE: The management of patients with intermediate coronary lesions is a major clinical issue. Fractional flow reserve (FFR) is considered the gold criterion for the assessment of ischaemic stenosis, but it requires an invasive procedure. Coronary computed tomography angiography (CTA) for fractional flow reserve (FFRCT) is a novel noninvasive alternative for the diagnosis of ischaemic lesions. The aim was to determine the diagnostic efficacy of FFRCT for ischaemic coronary artery stenosis lesions of intermediate severity. METHODS: A total of 129 patients underwent 64-row dual-source CTA and invasive coronary angiography (ICA). In all, 156 vessels were identified as intermediate-grade coronary artery stenosis by subsequent ICA, defined as a maximum diameter reduction of 50%-70%. The FFR was also measured during ICA. FFRCT was computed from the three-dimensional dual-source CTA model and coronary flow dynamics data. RESULTS: Per-patient diagnostic sensitivity, specificity, positive predictive values, negative predictive values and accuracy of FFRCT amounted to 89.2%, 81.5%, 66.0%, 94.9% and 83.7%, respectively; and 86.9%, 73.6%, 58.0%, 93.1% and 77.6% on the per-vessel basis, respectively. FFRCT and FFR showed a good positive correlation. Bland-Altman analysis displayed good concordance between FFRCT and FFR. The receiver operating characteristic curve revealed that the area under the curve of FFRCT was 0.918 (95% confidence interval 0.849-0.986) on the per-patient analysis and 0.916 (95% confidence interval 0.863-0.969) on per-vessel analysis, respectively. CONCLUSIONS: FFRCT is featured by moderate accuracy in discriminating lesions of intermediate coronary artery stenosis that cause myocardial ischaemia. Impact statement How to treat intermediate coronary stenosis represents a major clinical issue. FFRCT has recently emerged as a novel noninvasive method evaluating ischemic lesions. In this study, we defined such lesion as 50-70% diameter stenosis. We designed the study to assess the diagnostic efficacy of FFRCT both at per-vessel level and at per-vessel levels for ischemic lesions.

Delineation of epicardial stenosis in patients with microvascular disease using pressure drop coefficient: A pilot outcome study.

AIM: To investigate the patient-outcomes of newly developed pressure drop coefficient (CDP) in diagnosing epicardial stenosis (ES) in the presence of concomitant microvascular disease (MVD). METHODS: Patients from our clinical trial were divided into two subgroups with: (1) cut-off of coronary flow reserve (CFR) < 2.0; and (2) diabetes. First, correlations were performed for both subgroups between CDP and hyperemic microvascular resistance (HMR), a diagnostic parameter for assessing the severity of MVD. Linear regression analysis was used for these correlations. Further, in each of the subgroups, comparisons were made between fractional flow reserve (FFR) < 0.75 and CDP > 27.9 groups for assessing major adverse cardiac events (MACE: Primary outcome). Comparisons were also made between the survival curves for FFR < 0.75 and CDP > 27.9 groups. Two tailed chi-squared and Fischer's exact tests were performed for comparison of the primary outcomes, and the log-rank test was used to compare the Kaplan-Meier survival curves. P < 0.05 for all tests was considered statistically significant. RESULTS: Significant linear correlations were observed between CDP and HMR for both CFR < 2.0 (r = 0.58, P < 0.001) and diabetic (r = 0.61, P < 0.001) patients. In the CFR < 2.0 subgroup, the %MACE (primary outcomes) for CDP > 27.9 group (7.7%, 2/26) was lower than FFR < 0.75 group (3/14, 21.4%); P = 0.21. Similarly, in the diabetic subgroup, the %MACE for CDP > 27.9 group (12.5%, 2/16) was lower than FFR < 0.75 group (18.2%, 2/11); P = 0.69. Survival analysis for CFR < 2.0 subgroup indicated better event-free survival for CDP > 27.9 group (n = 26) when compared with FFR < 0.75 group (n = 14); P = 0.10. Similarly, for the diabetic subgroup, CDP > 27.9 group (n = 16) showed higher survival times compared to FFR group (n = 11); P = 0.58. CONCLUSION: CDP correlated significantly with HMR and resulted in better %MACE as well as survival rates in comparison to FFR. These positive trends demonstrate that CDP could be a potential diagnostic endpoint for delineating MVD with or without ES.

Assessment of left anterior descending artery stenosis of intermediate severity by fractional flow reserve, instantaneous wave-free ratio, and non-invasive coronary flow reserve.

To test the usefulness of non-invasive coronary flow reserve (CFR) by transthoracic Doppler echocardiography by comparison to invasive fractional flow reserve (FFR) and instantaneous wave-free ratio (IFR), a new vasodilator-free index of coronary stenosis severity, in patients with left anterior descending artery (LAD) stenosis of intermediate severity (IS) and stable coronary artery disease. 94 consecutive patients (mean age 68 ± 10 years) with angiographic LAD stenosis of IS (50-70 % diameter stenosis), were prospectively studied. IFR was calculated as a trans-lesion pressure ratio during the wave-free period in diastole; FFR as distal pressure divided by mean aortic pressure during maximal hyperemia (using 180 µg intracoronary adenosine); and CFR as hyperemic peak LAD flow velocity divided by baseline flow velocity using intravenous adenosine (140 µg/kg/min over 2 min). The mean values of IFR, FFR, and CFR were 0.88 ± 0.07, 0.81 ± 0.09, and 2.4 ± 0.6 respectively. A significant correlation was found between CFR and FFR (r = 0. 68), FFR and IFR (r = 0.6), and between CFR and IFR (r = 0.5) (all, p < 0.01). Using a ROC curve analysis, the best cut-off to detect a significant lesion based on FFR assessment (FFR ≤ 0.8, n = 31) was IFR ≤ 0.88 with a sensitivity (Se) of 74 %, specificity (Sp) of 73 %, AUC 0.81 ± 0.04, accuracy 72 %; and CFR ≤ 2 with a Se = 77 %, Sp = 89 %, AUC 0.88 ± 0.04, accuracy 85 % (all, p < 0.001). In stable patients with LAD stenosis of IS, non-invasive CFR is a useful tool to detect a significant lesion based on FFR. Furthermore, there was a better correlation between CFR and FFR than between CFR and IFR, and a trend to a better diagnostic performance for CFR versus IFR.

Predictive Value of Risk Factors Model for Major Adverse Cardiac Events in Patients with Intermediate Coronary Stenosis in Proximal Left Anterior Descending Artery / 医学研究杂志

Objective To investigate the risk factors of major adverse cardiac events (MACE) in patients with intermediate coronary stenosis in proximal left anterior descending artery (ICS-PLAD) and to assess the predictive value of risk factors model for MACE in patients with ICS-PLAD.Methods Totally 221 patients with ICS-PLAD (≥50％ and ＜70 ％ diameter stenosis by angiography) were retrospectively studied.The risk factors of MACE in patients with ICS-PLAD were explored by binary logistic regression analysis.The predictive value of risk factors model for MACE in patients with ICS-PLAD was evaluated by receiver operator curves (ROC).Results Compared with No MACE group,the MACE group had more patients with diabetes(DM),hypertension and number of stenotic vessels ≥ 2,had higher body mass index (BMI),low density lipoprotein cholesterol(LDL-C)and triglycerides(TG) (P all ＜ 0.05).Binary logistic regression analysis showed that the independent risk facts were TG (OR =2.447,P =0.000,95％ CI:1.608-3.725),LDL-C (OR =1.971,P =0.006,95 ％ CI:1.219-3.187) and number of stenotic vessels ≥ 2 (OR =6.596,P =0.000,95 ％ CI:2.995-14.526).The area under the ROC (AUG) of risk factor model for the prediction of MACE in patients with ICS-PLAD were 0.794 (P =0.000).Conclusion Patients with ICS-PLAD,with DM,hypertension,number of stenotic vessels ≥2,obesity,high LDL-C or high TG,had higher MACE rate.TG,LDL-C and number of stenotic vessels ≥2 were the independent risk factors of MACE in patients with ICS-PLAD.The risk factors model has some clinical value for the prediction of MACE in patients with ICS-PLAD.

Clinical outcomes of the vulnerable plaque sealing with drug-eluting stents for the treatment of intermedi-ate coronary stenosis / 实用医学杂志

Objective To evaluate the one-year clinical outcomes in patients with the vulnerable plaque sealing with drug-eluting stents for the treatment of intermediate coronary stenosis. Methods 327 patients with an-giographically intermediate lesions(diameter stenosis 50%~70%)with the vulnerable plaque which were detected by 64 slice coronary CT were prospectively enrolled. Patients were divided into medical therapy group (n = 160) and sirolimus-eluting stent group group(n=160). The incidences of one-year major adverse cardiovascular events (MACE)was evaluated(cardiac death,myocardial infarction ,revascularization). Results The MACE tended to be lower in the sirolimus-eluting stent group than medical therapy group(3.13%vs. 10%,log-rankχ2=6.62,P=0.01). The incident of cardiac death and myocardial infarction were lower in the sirolimus-eluting stent group than medical therapy group(1.25%vs. 5.63%,log-rankχ2=4.61,P=0.03). Conclusion The treatment of the siroli-mus-eluting stent can reduce MACE for the paitents with the vulnerable plaque of intermediate coronary stenosis than medical therapy only.

Clinical outcomes of the vulnerable plaque sealing with drug-eluting stents for the treatment of intermedi-ate coronary stenosis / 实用医学杂志

Objective To evaluate the one-year clinical outcomes in patients with the vulnerable plaque sealing with drug-eluting stents for the treatment of intermediate coronary stenosis. Methods 327 patients with an-giographically intermediate lesions(diameter stenosis 50%~70%)with the vulnerable plaque which were detected by 64 slice coronary CT were prospectively enrolled. Patients were divided into medical therapy group (n = 160) and sirolimus-eluting stent group group(n=160). The incidences of one-year major adverse cardiovascular events (MACE)was evaluated(cardiac death,myocardial infarction ,revascularization). Results The MACE tended to be lower in the sirolimus-eluting stent group than medical therapy group(3.13%vs. 10%,log-rankχ2=6.62,P=0.01). The incident of cardiac death and myocardial infarction were lower in the sirolimus-eluting stent group than medical therapy group(1.25%vs. 5.63%,log-rankχ2=4.61,P=0.03). Conclusion The treatment of the siroli-mus-eluting stent can reduce MACE for the paitents with the vulnerable plaque of intermediate coronary stenosis than medical therapy only.

Clinical outcomes of combined flow-pressure drop measurements using newly developed diagnostic endpoint: Pressure drop coefficient in patients with coronary artery dysfunction.

AIM: To combine pressure and flow parameter, pressure drop coefficient (CDP) will result in better clinical outcomes in comparison to the fractional flow reserve (FFR) group. METHODS: To test this hypothesis, a comparison was made between the FFR < 0.75 and CDP > 27.9 groups in this study, for the major adverse cardiac events [major adverse cardiac events (MACE): Primary outcome] and patients' quality of life (secondary outcome). Further, a comparison was also made between the survival curves for the FFR < 0.75 and CDP > 27.9 groups. Two-tailed χ (2) test proportions were performed for the comparison of primary and secondary outcomes. Kaplan-Meier survival analysis was performed to compare the survival curves of FFR < 0.75 and CDP > 27.9 groups (MedcalcV10.2, Mariakerke, Belgium). Results were considered statistically significant for P < 0.05. RESULTS: The primary outcomes (%MACE) in the FFR < 0.75 group (20%, 4 out of 20) was not statistically different (P = 0.24) from the %MACE occurring in CDP > 27.9 group (8.57%, 2 out of 35). Noteworthy is the reduction in the %MACE in the CDP > 27.9 group, in comparison to the FFR < 0.75 group. Further, the secondary outcomes were not statistically significant between the FFR < 0.75 and CDP > 27.9 groups. Survival analysis results suggest that the survival time for the CDP > 27.9 group (n = 35) is significantly higher (P = 0.048) in comparison to the survival time for the FFR < 0.75 group (n = 20). The results remained similar for a FFR = 0.80 cut-off. CONCLUSION: Based on the above, CDP could prove to be a better diagnostic end-point for clinical revascularization decision-making in the cardiac catheterization laboratories.

Association of coronary plaque burden with fractional flow reserve: should we keep attempting to derive physiology from anatomy?

Coronary computed tomography angiography (CTA) has been used increasingly for the diagnosis of coronary artery disease over the past decade. Compared to invasive coronary angiography (ICA), coronary CTA has the ability to visualize and quantify atherosclerotic plaque both calcified and non-calcified. Traditional measures of evaluating a coronary stenosis such as diameter stenosis, area stenosis, minimal lumen diameter and minimal luminal area are limited in their ability to predict its functional significance especially when diameter stenosis ranges between 30-69% (intermediate range). Measurement of invasive fractional flow reserve (FFR) is considered the gold standard for assessment of the hemodynamic significance of a stenosis. The current study by Nakazato et al. evaluates the performance of an emerging coronary CTA-derived anatomical measure "percent aggregate plaque volume" to improve the detection of hemodynamic significant stenosis as compared with invasive FFR.

Advanced computed tomographic anatomical and morphometric plaque analysis for prediction of fractional flow reserve in intermediate coronary lesions.

OBJECTIVE: To determine the application of advanced coronary computed tomography angiography (CCTA) plaque analysis for predicting invasive fractional flow reserve (FFR) in intermediate coronary lesions. METHODS: Sixty-one patients with 71 single intermediate coronary lesions (≥ 50-80% stenosis) on CCTA prospectively underwent coronary angiography and FFR. Advanced anatomical and morphometric plaque analysis was performed based on CCTA data set to determine optimal criteria for significant flow impairment. A significant stenosis was defined as FFR ≤ 0.80. RESULTS: FFR averaged 0.85 ± 0.09, and 19 lesions (27%) were functionally significant. FFR correlated with minimum lumen area (MLA) (r=0.456, p<0.001), minimum lumen diameter (MLD) (r=0.326, p=0.006), reference lumen diameter (RLD) (r=0.245, p=0.039), plaque burden (r=-0.313, p=0.008), lumen area stenosis (r=-0.305, p=0.01), lesion length (r=-0.692, p<0.001), and plaque volume (r=-0.668, p<0.001). There was no relationship between FFR and CCTA morphometric plaque parameters. By multivariate analysis the independent predictors of FFR were lesion length (beta=-0.581, p<0.001), MLA (beta=0.360, p=0.041), and RLD (beta=-0.255, p=0.036). The optimal cutoffs for lesion length, MLA, MLD, RLD, and lumen area stenosis were >18.5mm, ≤ 3.0mm(2), ≤ 2.1mm, ≤ 3.2mm, and >69%, respectively (max. sensitivity: 100% for MLA, max. specificity: 79% for lumen area stenosis). CONCLUSIONS: CCTA predictors for FFR support the mathematical relationship between stenosis pressure drop and coronary flow. CCTA could prove to be a useful rule-out test for significant hemodynamic effects of intermediate coronary stenoses.