Assessment of the Level of Matrix Metalloproteinases, VEGF and MicroRNA-34a in Patients With Non-obstructive and Obstructive Lesions of the Coronary Arteries.

AIM: To assess the levels of matrix metalloproteinases (MMP), vascular endothelial growth factor (VEGF), and miRNA-34a expression in patients with ischemic heart disease (IHD) and obstructive and nonobstructive coronary artery (CA) disease. MATERIAL AND METHODS: This cross-sectional observational study included 64 patients with IHD (diagnosis verified by coronary angiography or multislice computed tomography coronary angiography), of which 33 (51.6%) were men aged 64.9±8.1 years. 20 patients had nonobstructive CA disease (stenosis <50%), and 44 had hemodynamically significant stenoses. The control group consisted of 30 healthy volunteers. MMP-1, -9, -13, and -14, miRNA-34a, and VEGF were measured in all patients. RESULTS: The concentration of MMP-1 was significantly higher in patients with ischemia and nonobstructive CA disease (INOCAD) (p=0.016), and the concentration of MMP-9 was the highest in the group with obstructive CA disease (p<0.001). The concentrations of MMP-13 and MMP-14 did not differ significantly between the groups. The highest VEGF concentrations were observed in the INOCAD group (p<0.001). The expression of miRNA-34a significantly differed between the IHD groups with different types of CA disease and controls (p <0.001). Patients with hemodynamically significant stenosis showed moderate relationships between the concentrations of MMP-14 and VEGF (ρ=0.418; p=0.024), as well as between VEGF and miRNA-34a (ρ=0.425; p=0.022). Patients with INOCAD had a significant negative correlation between the concentrations of MMP-13 and VEGF (ρ= -0.659; p=0.003). Correlation analysis showed in all IHD patients a moderate relationship of the concentrations of MMP-1 and MMP-14 with VEGF (ρ=0.449; p=0.002 and p=0.341; p=0.019, respectively). According to ROC analysis, a MMP-9 concentration above 4.83 ng/ml can be a predictor for the presence of hemodynamically significant CA obstruction in IHD patients; a VEGF concentration higher than 27.23 pg/ml suggests the absence of hemodynamically significant CA stenosis. CONCLUSION: IHD patients with INOCAD had the greatest increase in MMP-1, whereas patients with obstructive CA disease had the highest level of MMP-9. According to our data, concentrations of MMP-9 and VEGF can be used to predict the degree of CA obstruction. The expression of miRNA-34a was significantly higher in IHD patients with INOCAD and CA obstruction than in the control group, which suggested a miRNA-34a contribution to the development and progression of coronary atherosclerosis. In the future, it may be possible to use this miRNA as a diagnostic marker for IHD.

Renal Dysfunction Increases Risk of Adverse Cardiovascular Events in 5-Year Follow-Up Study of Intermediate Coronary Artery Lesions.

BACKGROUND Progression of chronic coronary syndrome (CCS) is influenced by chronic kidney disease (CKD). This 5-year follow-up study aimed to assess 100 patients with 118 intermediate coronary artery lesions evaluated by fractional flow reserve (FFR) and intravascular imaging stratified according to renal function. MATERIAL AND METHODS This prospective study enrolled patients with intermediate coronary stenosis identified by coronary angiogram. Patients with severe renal dysfunction (estimated glomerular filtration rate (eGFR) <45 ml/min/1.73 m²) were excluded from the study. The remaining were divided into 2 groups according to eGFR: 45-60 ml/min/1.73 m² for mild-to-moderate renal dysfunction and >60 ml/min/1.73 m² for no renal dysfunction. We analyzed intermediate-grade stenoses (40-80% as assessed in coronary angiography) with the use of optical coherence tomography (OCT), FFR, and intravascular ultrasound (IVUS). RESULTS Renal dysfunction patients were older (67.7±8.1 vs 63.6±9.7 years, P=0.044). Lesion characteristics, including plaque type and minimal lumen area in OCT, showed no significant differences between the renal dysfunction and no renal dysfunction groups. Thin-cap fibroatheroma, calcific plaques, lipidic plaques, and fibrous plaques had similar prevalence. FFR values and IVUS parameters did not significantly differ between the groups. Over a 5-year follow-up, individuals with mild-to-moderate renal dysfunction had an elevated risk of all-cause mortality and major adverse cardiovascular events in multivariate analyses adjusted for age and sex. CONCLUSIONS Mild-to-moderate renal dysfunction was not associated with significant differences in OCT- and IVUS-derived plaque morphology nor with functional indices characterizing intermediate-grade coronary stenoses. Renal dysfunction was related to a higher risk of all-cause mortality and major adverse cardiovascular events prevalence in 5-year follow-up.

Evaluation of fractional flow reserve and atherosclerotic plaque characteristics on coronary non-contrast T1-weighted magnetic resonance imaging.

BACKGROUND AND AIMS: The relationship between high-risk coronary plaque characteristics regardless of the severity of lesion stenosis and myocardial ischemia remains unsettled. High-intensity plaques (HIPs) on non-contrast T1-weighted magnetic resonance imaging (T1WI) have been characterized as high-risk coronary plaques. We sought to elucidate whether the presence of coronary HIPs on T1WI influences fractional flow reserve (FFR) in the distal segment of the vessel. METHODS: We retrospectively analyzed 281 vessels in 231 patients with chronic coronary syndrome who underwent invasive FFR measurement and coronary T1WI using a multicenter registry. The plaque-to-myocardial signal intensity ratio (PMR) of the most stenotic lesion was evaluated; a coronary plaque with PMR ≥1.4 was defined as a HIP. RESULTS: The median PMR of coronary plaques on T1WI in vessels with FFR ≤0.80 was significantly higher than that of plaques with FFR >0.80 (1.17 [interquartile range (IQR): 0.99-1.44] vs. 0.97 [IQR: 0.85-1.09]; p < 0.001). Multivariable analysis showed that an increase in PMR of the most stenotic segment was associated with lower FFR (beta-coefficient, -0.050; p < 0.001). The presence of coronary HIPs was an independent predictor of FFR ≤0.80 (odds ratio (OR), 6.18; 95% confidence interval (CI), 1.93-19.77; p = 0.002). Even after adjusting for plaque composition characteristics based on computed tomography angiography, the presence of coronary HIPs was an independent predictor of FFR ≤0.80 (OR, 4.48; 95% CI, 1.19-16.80; p = 0.026). CONCLUSIONS: Coronary plaques with high PMR are associated with low FFR in the corresponding vessel, indicating that plaque morphology might influence myocardial ischemia severity.

Baseline coronary artery stenosis severity is an independent predictor of subsequent poor sleep quality in patients with acute coronary syndrome.

AIM: To investigate the relationship between coronary artery lesion severity determined using the baseline SYNTAX score and sleep problems that might occur after discharge determined using the Pittsburgh Sleep Quality Index (PSQI). METHODS: This prospective study included patients with first acute coronary syndrome (ACS) who underwent percutaneous coronary angiography between February 2019 and August 2019. The severity of coronary artery stenosis was classified according to coronary angiography and SYNTAX scores. Patients were grouped as those with a SYNTAX score of ≤22 and >22. Sleep quality after discharge was classified according to the PSQI. PSQI ≤5 represented good sleep quality, and PSQI >5 represented poor sleep quality. Univariate and multivariate logistic regression was used to investigate the relationship between sleep quality and coronary artery stenosis severity. RESULTS: A total of 424 patients were included in the study. Of these, 294 (69.34%) had a SYNTAX score of ≤22 and 130 (30.66%) had a SYNTAX score of >22. The mean age of all patients was 60.37 ±â€…12.23 years, 59.69 ±â€…11.85 years in the SYNTAX ≤22 groups and 61.90 ±â€…12.98 years in the SYNTAX >22 group (P = 0.086). The majority (78.54%) of the patients were male and there was no significant difference between the SYNTAX ≤22 group and the SYNTAX >22 group in terms of sex distribution (P = 0.383). According to the univariate logistic regression analysis, age (P = 0.014), diabetes (P = 0.027), left ventricular ejection fraction (P = 0.001), estimated glomerular filtration rate (P = 0.039), creatine kinase MB (P = 0.040) and SYNTAX scores (P < 0.001) were significantly associated with high PSQI global scores (>5). However, according to the multivariate logistic regression analysis results, high (>22) SYNTAX scores were the only factor independently associated with the high (>5) PSQI global scores [odds ratio, 3.477; 95% confidence interval (CI), (2.190-5.522); P < 0.001]. Complete revascularization group had significantly higher sleep latency and sleep duration time, sleep efficiency and the percentage of patients with PSQI global score of ≤5 than the incomplete revascularization group (P < 0.001 for all). CONCLUSION: Among patients with ACS, those with high SYNTAX scores should be monitored more carefully for sleep disorders that may occur later.

The additive effect of metabolic syndrome on left ventricular impairment in patients with obstructive coronary artery disease assessed by 3.0 T cardiac magnetic resonance feature tracking.

BACKGROUND: Metabolic syndrome (MetS) can increase the risk of morbidity and mortality of cardiovascular disease and obstructive coronary artery disease (OCAD), which usually have a poor prognosis. This study aimed to explore the impact of MetS on left ventricular (LV) deformation and function in OCAD patients and investigate the independent factors of impaired LV function and deformation. MATERIALS AND METHODS: A total of 121 patients with OCAD and 52 sex- and age-matched controls who underwent cardiac magnetic resonance scanning were enrolled in the study. All OCAD patients were divided into two groups: OCAD with MetS [OCAD(MetS+), n = 83] and OCAD without MetS [OCAD(MetS-), n = 38]. LV functional and global strain parameters were measured and compared among the three groups. Multivariable linear regression analyses were constructed to investigate the independent factors of LV impairment in OCAD patients. Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were performed to test the prediction efficiency of MetS for LV impairment. RESULTS: From controls to the OCAD(MetS-) group to the OCAD(MetS+) group, LV mass (LVM) increased, and LV global function index (LVGFI) and LV global longitudinal peak strain (GLPS) decreased (all p < 0.05). Compared with the OCAD(MetS-) group, the LV GLPS declined significantly (p = 0.027), the LVM increased (p = 0.006), and the LVGFI decreased (p = 0.043) in the OCAD(MetS+) group. After adjustment for covariates in OCAD patients, MetS was an independent factor of decreased LV GLPS (ß = - 0.211, p = 0.002) and increased LVM (ß = 0.221, p = 0.003). The logistic multivariable regression analysis and ROC analysis showed that combined MetS improved the efficiency of predicting LV GLPS reduction (AUC = 0.88) and LVM (AUC = 0.89) increase. CONCLUSIONS: MetS aggravated the damage of LV deformation and function in OCAD patients and was independently associated with LV deformation and impaired LV strain. Additionally, MetS increased the prediction efficiency of increased LVM and decreased LV GLPS. Early detection and intervention of MetS in patients with OCAD is of great significance.

Lesion Eccentricity Plays a Key Role in Determining the Pressure Gradient of Serial Stenotic Lesions: Results from a Computational Hemodynamics Study.

PURPOSE: In arterial disease, the presence of two or more serial stenotic lesions is common. For mild lesions, it is difficult to predict whether their combined effect is hemodynamically significant. This study assessed the hemodynamic significance of idealized serial stenotic lesions by simulating their hemodynamic interaction in a computational flow model. MATERIALS AND METHODS: Flow was simulated with SimVascular software in 34 serial lesions, using moderate (15 mL/s) and high (30 mL/s) flow rates. Combinations of one concentric and two eccentric lesions, all 50% area reduction, were designed with variations in interstenotic distance and in relative direction of eccentricity. Fluid and fluid-structure simulations were performed to quantify the combined pressure gradient. RESULTS: At a moderate flow rate, the combined pressure gradient of two lesions ranged from 3.8 to 7.7 mmHg, which increased to a range of 12.5-24.3 mmHg for a high flow rate. Eccentricity caused an up to two-fold increase in pressure gradient relative to concentric lesions. At a high flow rate, the combined pressure gradient for serial eccentric lesions often exceeded the sum of the individual lesions. The relative direction of eccentricity altered the pressure gradient by 15-25%. The impact of flow pulsatility and wall deformability was minor. CONCLUSION: This flow simulation study revealed that lesion eccentricity is an adverse factor in the hemodynamic significance of isolated stenotic lesions and in serial stenotic lesions. Two 50% lesions that are individually non-significant can combine more often than thought to hemodynamic significance in hyperemic conditions.

Predictive value of plaque characteristics for identification of lesions causing ischemia.

BACKGROUND: Functional assessment using fractional flow reserve (FFR) and anatomical assessment using optical coherence tomography (OCT) are used in clinical practice for patients with intermediate coronary stenosis. Moreover, coronary computed tomography angiography (CTA) is a common noninvasive imaging technique for evaluating suspected coronary artery disease before being referred for angiography. This study aimed to investigate the association between FFR and plaque characteristics assessed using coronary CTA and OCT for intermediate coronary stenosis. METHODS: Based on a prospective multicenter registry, 159 patients having 339 coronary lesions with intermediate stenosis were included. All patients underwent coronary CTA before being referred for coronary angiography, and both FFR measurements and OCT examinations were performed during angiography. A stenotic lesion identified with FFR ≤0.80 was deemed diagnostic of an ischemia-causing lesion. The predictive value of plaque characteristics assessed using coronary CTA and OCT for identifying lesions causing ischemia was analyzed. RESULTS: Stenosis severity and plaque characteristics on coronary CTA and OCT differed between lesions that caused ischemia and those that did not. In multivariate analysis, low attenuation plaque on coronary CTA (odds ratio [OR]=2.78; P=0.038), thrombus (OR=5.13; P=0.042), plaque rupture (OR=3.25; P=0.017), and intimal vasculature on OCT (OR=2.57; P=0.012) were independent predictors of ischemic lesions. Increasing the number of these plaque characteristics offered incremental improvement in predicting the lesions causing ischemia. CONCLUSIONS: Comprehensive anatomical evaluation of coronary stenosis may provide additional supportive information for predicting the lesions causing ischemia.

Mechanisms of coronary sinus reducer for treatment of myocardial ischemia: in silico study.

The coronary sinus reducer (CSR) is an emerging medical device for treating patients with refractory angina, often associated with myocardial ischemia. Patients implanted with CSR have shown positive outcomes, but the underlying mechanisms are unclear. This study sought to understand the mechanisms of CSR by investigating its effects on coronary microcirculation hemodynamics that may help explain the therapy's efficacy. We applied a validated computer model of the coronary microcirculation to investigate how CSR affects hemodynamics under different degrees of coronary artery stenosis. With moderate coronary stenosis, an increase in capillary transit time (CTT) [up to 69% with near-complete coronary sinus (CS) occlusion] is the key change associated with CSR. Because capillaries in the microcirculation can still receive oxygenated blood from the upstream artery with moderate stenosis, the increase in CTT allows more time for the exchange of gases and nutrients, aiding tissue oxygenation. With severe coronary stenosis; however, the redistribution of blood draining from the nonischemic region to the ischemic region (up to 96% with near-complete CS occlusion) and the reduction in capillary flow heterogeneity are the key changes associated with CSR. Because blood draining from the nonischemic region is not completely devoid of O2, the redistribution of blood to the capillaries in the ischemic region by CSR is beneficial especially when little or no oxygenated blood reaches these capillaries. This simulation study provides insights into the mechanisms of CSR in improving clinical symptoms. The mechanisms differ with the severity of the upstream stenosis.NEW & NOTEWORTHY Emerging coronary venous retroperfusion treatments, particularly coronary sinus reducer (CSR) for refractory angina linked to myocardial ischemia, show promise; however, their mechanisms of action are not well understood. We find that CSR's effectiveness varies with the severity of coronary stenosis. In moderate stenosis, CSR improves tissue oxygenation by increasing capillary transit time, whereas in severe stenosis, it redistributes blood from nonischemic to ischemic regions and reduces capillary flow heterogeneity.

Coronary computed tomography angiography derived fractional flow reserve and risk of recurrent angina: A 3-year follow-up study.

BACKGROUND: The association between coronary computed tomography angiography (CTA) derived fractional flow reserve (FFRCT) and risk of recurrent angina in patients with new onset stable angina pectoris (SAP) and stenosis by CTA is uncertain. METHODS: Multicenter 3-year follow-up study of patients presenting with symptoms suggestive of new onset SAP who underwent first-line CTA evaluation and subsequent standard-of-care treatment. All patients had at least one ≥30 â€‹% coronary stenosis. A per-patient lowest FFRCT-value ≤0.80 represented an abnormal test result. Patients with FFRCT ≤0.80 who underwent revascularization were categorized according to completeness of revascularization: 1) Completely revascularized (CR-FFRCT), all vessels with FFRCT ≤0.80 revascularized; or 2) incompletely revascularized (IR-FFRCT) ≥1 vessels with FFRCT ≤0.80 non-revascularized. Recurrent angina was evaluated using the Seattle Angina Questionnaire. RESULTS: Amongst 769 patients (619 [80 â€‹%] stenosis ≥50 â€‹%, 510 [66 â€‹%] FFRCT ≤0.80), 174 (23 â€‹%) reported recurrent angina at follow-up. An FFRCT ≤0.80 vs â€‹> â€‹0.80 associated to increased risk of recurrent angina, relative risk (RR): 1.82; 95 â€‹% CI: 1.31-2.52, p â€‹< â€‹0.001. Risk of recurrent angina in CR-FFRCT (n â€‹= â€‹135) was similar to patients with FFRCT >0.80, 13 â€‹% vs 15 â€‹%, RR: 0.93; 95 â€‹% CI: 0.62-1.40, p â€‹= â€‹0.72, while IR-FFRCT (n â€‹= â€‹90) and non-revascularized patients with FFRCT ≤0.80 (n â€‹= â€‹285) had increased risk, 37 â€‹% vs 15 â€‹% RR: 2.50; 95 â€‹% CI: 1.68-3.73, p â€‹< â€‹0.001 and 30 â€‹% vs 15 â€‹%, RR: 2.03; 95 â€‹% CI: 1.44-2.87, p â€‹< â€‹0.001, respectively. Use of antianginal medication was similar across study groups. CONCLUSION: In patients with SAP and coronary stenosis by CTA undergoing standard-of-care guided treatment, FFRCT provides information regarding risk of recurrent angina.

Preprocedural transthoracic Doppler echocardiography to identify stenosis associated with increased coronary flow after revascularisation.

The benefit of percutaneous coronary intervention (PCI) has been reported to be associated with functional stenosis severity defined by fractional flow reserve (FFR). This study aimed to investigate the predictive ability of preprocedural transthoracic Doppler echocardiography (TDE) for increased coronary flow. A total of 50 left anterior descending arteries (LAD) that underwent TDE examinations were analysed. Hyperaemic LAD diastolic peak velocity (hDPV) was used as a surrogate of volumetric coronary flow. The increase in coronary flow was evaluated by the metric of % hDPV-increase defined by 100× (post-PCI hDPV-pre-PCI hDPV)/pre-PCI hDPV. The two groups divided by the median value of % hDPV-increase were compared, and the determinants of a significant coronary flow increase defined as more than the median % hDPV-increase were explored. After PCI, FFR values improved in all cases. hDPV significantly increased from 53.0 to 76.0 mm/s (P < 0.01) and the median % hDPV-increase was 45%, while hDPV decreased in 10 patients. On multivariable analysis, pre-PCI FFR and hDPV were independent predictors of a significant coronary flow increase. Preprocedural TDE-derived hDPV provided significant improvement of identification of lesions that benefit from revascularisation with respect to significant coronary flow increase.

Diagnostic performance of deep learning and computational fluid dynamics-based instantaneous wave-free ratio derived from computed tomography angiography.

BACKGROUND AND OBJECTIVES: Both fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are widely used to evaluate ischemia-causing coronary lesions. A new method of CT-iFR, namely AccuiFRct, for calculating iFR based on deep learning and computational fluid dynamics (CFD) using coronary computed tomography angiography (CCTA) has been proposed. In this study, the diagnostic performance of AccuiFRct was thoroughly assessed using iFR as the reference standard. METHODS: Data of a total of 36 consecutive patients with 36 vessels from a single-center who underwent CCTA, invasive FFR, and iFR were retrospectively analyzed. The CT-derived iFR values were computed using a novel deep learning and CFD-based model. RESULTS: Mean values of FFR and iFR were 0.80 ± 0.10 and 0.91 ± 0.06, respectively. AccuiFRct was well correlated with FFR and iFR (correlation coefficients, 0.67 and 0.68, respectively). The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of AccuiFRct ≤ 0.89 for predicting FFR ≤ 0.80 were 78%, 73%, 81%, 73%, and 81%, respectively. Those of AccuiFRct ≤ 0.89 for predicting iFR ≤ 0.89 were 81%, 73%, 86%, 79%, and 82%, respectively. AccuiFRct showed a similar discriminant function when FFR or iFR were used as reference standards. CONCLUSION: AccuiFRct could be a promising noninvasive tool for detection of ischemia-causing coronary stenosis, as well as facilitating in making reliable clinical decisions.

Effect of Calcification Based on Computer-Aided System on CT-Fractional Flow Reserve in Diagnosis of Coronary Artery Lesion.

This study was to analyze the diagnostic value of coronary computed tomography angiography (CCTA) and fractional flow reserve (FFR) based on computer-aided diagnosis (CAD) system for coronary lesions and the possible impact of calcification. 80 patients who underwent CCTA and FFR examination in hospital were selected as the subjects. The FFR value of 0.8 was used as the dividing line and divided into the ischemic group (FFR ≤ 0.8) and nonischemic group (FFR > 0.8). The basic data and imaging characteristics of patients were analyzed. The maximum diameter stenosis rate (MDS %), maximum area stenosis rate (MAS %), and napkin ring sign (NRS) in the ischemic group were significantly lower than those in the nonischemic group (P < 0.05). Remodeling index (RI) and eccentric index (EI) compared with the nonischemic group had no significant difference (P > 0.05). The total plaque volume (TPV), total plaque burden (TPB), calcified plaque volume (CPV), lipid plaque volume (LPV), and lipid plaque burden (LPB) in the ischemic group were significantly different from those in the non-ischemic group (P < 0.05). MAS % had the largest area under curve (AUC) for the diagnosis of coronary myocardial ischemia (0.74), followed by MDS % (0.69) and LPV (0.68). CT-FFR had high diagnostic sensitivity, specificity, accuracy, truncation value, and AUC area data for patients in the ischemic group and nonischemic group. The diagnostic sensitivity, specificity, accuracy, cutoff value, and AUC area data of CT-FFR were higher in the ischemic group (89.93%, 92.07%, 95.84%, 60.51%, 0.932) and nonischemic group (93.75%, 90.88%, 96.24%, 58.22%, 0.944), but there were no significant differences between the two groups (P > 0.05). In summary, CT-FFR based on CAD system has high accuracy in evaluating myocardial ischemia caused by coronary artery stenosis, and within a certain range of calcification scores, calcification does not affect the diagnostic accuracy of CT-FFR.

Reliability of Fractional Flow Reserve and Instantaneous Wave-Free Ratio in Assessing Intermediate Coronary Stenosis in Patients With Atrial Fibrillation.

Despite the current use of fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) for guiding revascularization in atrial fibrillation (AF), there is a lack of studies evaluating their reliability in this particular population. This retrospective study aimed to investigate the reliability of FFR and iFR in patients with AF. This retrospective study included all patients with AF undergoing FFR measurements (n = 45 vessels from 36 patients) at Brugmann University Hospital, Brussels, Belgium, between 2012 and 2020 or iFR (n = 18 vessels from 13 patients) and a corresponding number of patients with sinus rhythm (SR) randomly selected from the same period, benefiting from iFR (n = 20 vessels from 17 patients) or FFR (n = 50 vessels from 37 patients). Our main findings indicate that there is an increased beat-to-beat variability of individual iFR measures in patients with AF, compared with SR. In addition, the reproducibility of iFR on test-retest is low in patients with AF, leading to increased lesion reclassification (53.8% of lesions reclassified on 2 consecutive iFR measurements in AF vs 6.6% lesions reclassified in SR, p <0.05). In contrast, FFR seems to be more robust in evaluating coronary lesions in AF in terms of equivalent variability, reproducibility, and lesion reclassification observed in the SR population. In conclusion, this is the first study to evaluate the reliability of iFR and FFR in AF. Our findings raise caution in using iFR to guide revascularization in patients with AF, whereas FFR seems to be more robust in this population.

Predictors of fractional flow reserve/instantaneous wave-free ratio discordance: impact of tailored diagnostic cut-offs on clinical outcomes of deferred lesions.

BACKGROUND: Patient-related and lesion-related factors may influence instantaneous wave-free ratio (iFR)/fractional flow reserve (FFR) concordance, potentially affecting the safety of revascularization deferral. METHODS: Consecutive patients with at least an intermediate coronary stenosis evaluated by both iFR and FFR were retrospectively enrolled. The agreement between iFR and FFR at their diagnostic cut-offs (FFR 0.80, iFR 0.89) was assessed. Predictors of discordance were assessed using multivariate analyses. Tailored iFR cut-offs according to predictors of discordance best matching an FFR of 0.80 were identified. The impact of reclassification according to tailored iFR cut-offs on major cardiovascular events (MACE: cardiovascular death, myocardial infarction or target-lesion revascularization) among deferred lesions was investigated. RESULTS: Two hundred and ninety-nine intermediate coronary stenosis [FFR 0.84 (0.78-0.89), iFR 0.91 (0.87-0.95), 202 left main/left anterior descending (LM/LAD) vessels, 67.6%] of 260 patients were studied. Discordance rate was 23.4% (n = 70, 10.7% iFR-negative discordant, 12.7% iFR-positive discordant). Predictors of discordance were LM/LAD disease, multivessel disease, non-ST-elevation myocardial infarction, smoking, reduced eGFR and hypertension. Lesion reclassification with tailored iFR cut-offs based on patient-level predictors carried no prognostic value among deferred lesions. Reclassification according to lesion location, which was entirely driven by LM/LAD lesions (iFR cut-offs: 0.93 for LM/LAD, 0.89 for non-LM/LAD), identified increased MACE among lesions deferred based on a negative FFR, between patients with a positive as compared with a negative iFR (19.4 vs. 6.1%, P = 0.044), whereas the same association was not observed with the conventional 0.89 iFR cut-off (15 vs. 8.6%, P = 0.303). CONCLUSION: Tailored vessel-based iFR cut-offs carry prognostic value among FFR-negative lesions, suggesting that a one-size-fit-all iFR cut-off might be clinically unsatisfactory.

Predicting haemodynamic significance of coronary stenosis with radiomics-based pericoronary adipose tissue characteristics.

AIM: To investigate the diagnostic performance of the radiomics features of pericoronary adipose tissue (PCAT) in determining haemodynamically significant coronary artery stenosis as evaluated by fractional flow reserve (FFR). MATERIALS AND METHODS: A total of 92 patients with clinically suspected coronary artery disease who underwent coronary computed tomography (CT) angiography (CCTA), invasive coronary angiography (ICA), and FFR examination within 1 month were included retrospectively, and 121 lesions were randomly assigned to the training and testing set. Based on manual segmentation of PCAT, 1,116 radiomics features were computed. After radiomics robustness assessment and feature selection, radiomics models were established using the different machine-learning algorithms. The area under the receiver operating characteristic (ROC) curve (AUC) and net reclassification index (NRI) were analysed to compare the discrimination and reclassification abilities of radiomics models. RESULTS: Two radiomics features were selected after exclusions, and both were significantly higher in coronary arteries with FFR ≤0.8 than those with FFR >0.8. ROC analysis showed that the combination of CCTA and decision tree radiomics model achieved significantly higher diagnostic performance (AUC: 0.812) than CCTA alone (AUC: 0.599, p=0.015). Furthermore, the NRI of the combined model was 0.820 and 0.775 in the training and testing sets, respectively, suggesting the radiomics features of PCAT had were effective in classifying the haemodynamic significance of coronary stenosis. CONCLUSIONS: Adding PCAT radiomics features to CCTA enabled identification of haemodynamically significant coronary artery stenosis.

Aumento do trabalho miocárdico desperdiçado como indicador de lesão coronariana significativa / Increased wasted myocardial work as an indicator of significant coronary lesion

Introdução: A avaliação dos índices de trabalho miocárdico global em condições basais pode ser útil para a estratificação clínica de pacientes com suspeita de obstrução coronariana. Objetivo: Correlacionar o valor do índice de trabalho miocárdico global e a presença de lesões obstrutivas coronarianas significativas. Método: Estudo transversal, com pacientes encaminhados para cinecoronarioangiografia eletiva. Foi realizado ecocardiograma com obtenção das medidas para cálculo do valor do trabalho miocárdico, sendo avaliada a presença de lesões obstrutivas coronarianas significativas à cinecoronarioangiografia. Resultados: A amostra foi composta de 30 pacientes, com a idade média de 64,2±12,8 anos, sendo a maioria do sexo masculino (63,3%), dos quais 68,4% apresentaram lesões obstrutivas coronarianas significativas. O índice de trabalho miocárdico global foi de 1.876mmHg%±253,8 no grupo com lesões obstrutivas coronarianas significativas e de 2.054,2mmHg%±417,3 naqueles sem lesões significativas (p=0,089). O trabalho miocárdio construtivo global nos pacientes sem lesões obstrutivas coronarianas significativas foi maior (2.329,3mmHg%±462,9) do que naqueles com lesões obstrutivas coronarianas significativas (2.109,5mmHg%±332,3; p=0,064). O trabalho miocárdio desperdiçado global foi maior nos pacientes com lesões obstrutivas coronarianas significativas (103,7mmHg%±47,1 versus 68,3mmHg%±33,8; p=0,038). O ponto de corte de 115mmHg% foi aquele com a melhor área sob a curva (0,625), com sensibilidade de 83,3%. Conclusão: O aumento do trabalho miocárdio desperdiçado global se correlacionou com a presença de lesões obstrutivas coronarianas significativas em nossa amostra.(AU)

Introduction: The assessment of global myocardial work indices under baseline conditions may be useful for the clinical stratification of patients with suspected coronary obstruction. Objective: To correlate the value of global myocardial work indices and the presence of significant obstructive coronary lesions. Method: Cross-sectional study, with patients referred for elective coronary angiography. An echocardiogram was performed to obtain measurements to calculate the value of myocardial work and evaluated the presence or presence of significant obstructive coronary lesions at coronary angiography. Results: The sample consisted of 30 patients, with a mean age of 64.2±12.8 years, the majority being male (63.3%), of which 68.4% had significant obstructive coronary lesions. The global myocardial work indices was 1,876mmHg%±253.8 in the group with significant obstructive coronary lesions and 2,054.2mmHg%±417.3 in those without significant lesions (p=0.089). Global constructive myocardial work in patients without significant obstructive coronary lesions was higher (2,329.3mmHg%±462.9) than in those with significant obstructive coronary lesions (2,109.5mmHg%±332.3; p=0.064). Global wasted myocardial work was higher in patients with significant obstructive coronary lesions (103.7mmHg%±47.1 versus 68.3mmHg%±33.8; p=0.038). The cutoff point of 115 mmHg% was the one with the best area under the curve (0.625), with a sensitivity of 83.3%. Conclusion: The increase in global wasted myocardial work correlated with the presence of significant obstructive coronary lesions in our sample. (AU)