Study on the characteristics of coronary calcification by Intravascular Ultrasound (IVUS)

Background: Percutaneous coronary angiography is considered the "gold standard" for the diagnosis of coronary artery disease and provides the necessary anatomical information to provide appropriate treatment. The limitation of coronary angiography is the accurate assessment of calcified coronary lesions. Intravascular ultrasonography has many advantages in the assessment of calcified coronary lesions. Methods: The descriptive clinical study. Evaluation of calcified coronary artery lesions by intravascular ultrasound Results: From January 2019 to December 2019, at the Hanoi Heart Institute, 64 patients had 64 coronary artery lesions surveyed by intravascular ultrasound. There were 42 (65,6%) calcified lesions assessed by IVUS and 25 (39,1%) calcified lesions were detected by coronary angiography. In addition, the location of calcified were revealed more in the LAD compared to other: LAD 60%, LCx 24%, RCA 12% and LM 4%. Conclusion: IVUS calcification detection rate is higher than coronary angiography. The most common site of calcification in the LAD.

Effect of Coronary Calcification Severity on Measurements and Diagnostic Performance of CT-FFR With Computational Fluid Dynamics: Results From CT-FFR CHINA Trial

Aims: To explore the effect of coronary calcification severity on the measurements and diagnostic performance of computed tomography-derived fractional flow reserve (FFR; CT-FFR).Methods: This study included 305 patients (348 target vessels) with evaluable coronary calcification (CAC) scores from CT-FFR CHINA clinical trial. The enrolled patients all received coronary CT angiography (CCTA), CT-FFR, and invasive FFR examinations within 7 days. On both per-patient and per-vessel levels, the measured values, accuracy, and diagnostic performance of CT-FFR in identifying hemodynamically significant lesions were analyzed in all CAC score groups (CAC = 0, > 0 to <100, ≥ 100 to <400, and ≥ 400), with FFR as reference standard.Results: In total, the sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under receiver operating characteristics curve (AUC) of CT-FFR were 85.8, 88.7, 86.9, 87.8, 87.1%, 0.90 on a per-patient level and 88.3, 89.3, 89.5, 88.2, 88.9%, 0.88 on a per-vessel level, respectively. Absolute difference of CT-FFR and FFR values tended to elevate with increased CAC scores (CAC = 0: 0.09 ± 0.10; CAC > 0 to <100: 0.06 ± 0.06; CAC ≥ 100 to <400: 0.09 ± 0.10; CAC ≥ 400: 0.11 ± 0.13; p = 0.246). However, no statistically significant difference was found in patient-based and vessel-based diagnostic performance of CT-FFR among all CAC score groups.Conclusion: This prospective multicenter trial supported CT-FFR as a viable tool in assessing coronary calcified lesions. Although large deviation of CT-FFR has a tendency to correlate with severe calcification, coronary calcification has no significant influence on CT-FFR diagnostic performance using the widely-recognized cut-off value of 0.8.

Comparability of coronary risk assessment methods with chest ultra-LDCT and CT coronography with ECG synchronization

Purpose. To assess the comparability of coronary calcium values measured on ultralow-dose computed tomography studies without ECG-synchronization versus a) non-contrast computed tomography with ECG synchronization, b) CT coronography with ECG synchronization.Materials and methods. The study comprised 283 studies: 68 patients who underwent contrast-free ultra-LDCT without ECG synchronization and contrast-free CT with ECG synchronization performed in a single visit, and 49 patients with contrast-free ultra-LDCT without ECG synchronization, non-contrast CT with ECG synchronization, and CT coronography with ECG synchronization and intravenous injection of contrast agent, also carried out in one visit, meeting all inclusion and exclusion criteria of the study.Quantitative coronary calcium values were calculated with the Agatston score and the CAC-DRS scale (score of calcification degree from 0 to 3 and the number of affected arteries from 0 to 4 points). The degree of coronary artery stenosis was analyzed with CAD-RADS scale (0-5).The above parameters were compared using visual/quantitative assessment of coronary calcium on ultra-LDCT without ECG synchronization and visual/quantitative assessment for CT with ECG synchronization, as well as the degree of stenosis on CT coronography in the same patients.Results. Based on the results of accuracy indices comparison, the possibility to use quantitative scale (Agatston score, CAC-DRS quantitative scale) to assess coronary calcification in the lung cancer screening in comparison with ECG-synchronized CT was determined during interpretation of ultra-LDCT without ECG synchronization. The correlation matrix to assess correlation between visual, quantitative scales of coronary artery changes and calcification at ultra-LDCT without ECG synchronization and quantitative scale at CT with ECG synchronization vs. CT coronography identifies very strong positive statistically significant correlations.Conclusion. Methods of coronary calcinosis assessment with chest ultra-LDCT and CT with ECG synchronization are comparable, therefore it is possible to assess coronary calcium in lung cancer screening by ultra-LDCT data at a reliable-high level using both quantitative and visual CAC-DRS scales.

Effect of lesion characteristics on diagnostic performance of CT-derived fractional flow reserve: exploring the indications for application based on CT-FFR CHINA trial (Preprint)

BACKGROUND High diagnostic performance of coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR; CT-FFR) in identifying flow-limiting stenosis has been confirmed. CT-FFR is recommended to assess the hemodynamic significance of coronary lesions. However, the optimal indications of CT-FFR relies on its ability to discriminating ischemia in situations of different types of lesions. And the effect of lesion-dependent factors on determining the diagnostic accuracy of CT-FFR have not been comprehensively evaluated yet. OBJECTIVE We aimed to investigate the effect of lesion-related factors on the diagnostic performance of CT-FFR with computational fluid dynamics algorithm, to promote the clinical application of it. METHODS This multicenter prospective clinical trial enrolled 317 patients with 30%–90% stenosis undergoing CCTA and invasive FFR from 5 centers across China. All target lesions were assigned into different lesion characteristics (target vessels, lesion location, lesion length, bifurcation lesions, and coronary calcification) subgroups. Diagnostic performance (accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under receiver operating characteristics curve (AUC)) of CT-FFR identifying ischemia were calculated and compared in all sub-groups. RESULTS Three hundred and sixty-six target vessels from 317 patients (mean age: 59.3 ± 9.6 years) were analyzed. The overall vessel-based diagnostic accuracy, sensitivity, specificity, PPV, NPV, and AUC of CT-FFR were 87.2%, 86.4%, 88.8%, 86.9%, 88.4%, and 0.90. Absence of bifurcation lesion group possessed the higher NPV of CT-FFR than presence of bifurcation lesion group (92.8% vs. 78.9%, p = 0.006). Whereas there was no statistically significant difference in diagnostic performance of CT-FFR among different target vessels, lesion location, lesion length, and coronary calcification sub-groups (all p > 0.05). CONCLUSIONS This study supported CT-FFR as a powerful noninvasive functional assessment tool for coronary lesions with different lesion characteristics, involving target vessel, lesion location, lesion length, and coronary calcification. While the diagnostic performance of CT-FFR was negatively affected by the presence of bifurcation lesions. CLINICALTRIAL https://clinicaltrials.gov; Unique identifier: NCT03692936.

Study On Coronary Dissection Complication Caused by Uneven Rotational Atherectomy Due To Guidewire Bias for Severe Calcified Lesions

BACKGROUND In the treatment of coronary calcification by rotational atherectomy (ROTA), guidewire bias is often considered to lead to procedure associated coronary dissections or perforations. However, the actual meaning of guidewire bias is unclear, though it usually refers to the cross-section location of the intravascular imaging (IVI) catheter in the coronary artery. OBJECTIVES This study tentatively explores the quantitative criteria in optical coherence tomography (OCT) imaging of guidewire bias which may cause ROTA induced coronary dissection. METHODS A total of twenty-one patients with severe calcified coronary lesions who has undergone ROTA treatment were enrolled in our study. These patients were detected by OCT successfully pre- and post-ROTA. All the observational coronary segments were analyzed cross-sectionally at every mm interval after manual coregistration of OCT imaging pre- and post-ROTA. ROTA related coronary dissection was the primary endpoint. RESULTS A total of 388 OCT cross-sectional images were effectively measured and analyzed for distribution and characteristics of plaque and OCT catheter location pre-ROTA, and the presence or absence of coronary dissections post-ROTA after manual coregistration. According to the receiver operating characteristic (ROC) analysis, distance from the center of OCT catheter to media at the bias direction (Dcmb) (area under the curve (AUC): 1.000, p<0.001, 95% confidence intervals (CI): 0.999 to 1.000) and touch angle (AUC: 0.988, p<0.001, 95%CI: 0.968 to 1.000) had a higher correlation with ROTA-related coronary dissection with the corresponding cutoff value of 0.720mm and 98.2º significantly. CONCLUSIONS Dcmb and touch angle detected by OCT are two very valuable and convenient independent predictors of ROTA-related coronary intimal dissections caused by guidewire bias.

Myocardial uptake of 68Ga-DOTATATE: correlation with cardiac disease and risk factors

Background Myocardial uptake on 68Ga-DOTATATE PET/CT is often observed and its clinical relevance is poorly understood. Purpose To detect any correlation between myocardial uptake of 68Ga-DOTATATE and presence of cardiac disease or risk factors. Material and Methods In this institutional review board-approved retrospective study, we reviewed 68Ga-DOTATATE PET/CT scans in our institution between 1 May 2018 and 30 September 2018. A semi-quantitative score (MUS) for myocardial uptake of 68Ga-DOTATATE was developed by measuring mean standardized uptake value (SUV) in five myocardial regions, corrected by blood pool activity, and MUS was validated between two readers. We investigated the relationship between MUS and presence of cardiac disease or risk factors, including Framingham score and coronary calcification. Results A total of 145 scans were included (79 women; mean age = 56.9 ± 13.7 years). Inter-reader agreement was excellent with intraclass correlation coefficient (r) = 0.964 (95% confidence interval [CI] = 0.903–0.987; P < 0.001). There was a weak but significant positive correlation between MUS and presence of coronary calcifications (Spearman rho = 0.20; P = 0.016). MUS was higher in patients with heart disease or risk factors (n = 83, mean MUS 2.03, 95% CI = 1.85–2.21) compared to those without (n = 23, mean MUS 1.40, 95% CI = 1.17–1.62; P < 0.001), although the cardiac disease group was older with a higher percentage of men (62.0 years, 57.8% men compared to 47.6 years, 13.0% men; P value <0.0001 for both comparisons). Conclusion For patients undergoing 68Ga-DOTATATE PET/CT scan, an elevated MUS might indicate an underlying heart disease.

Association of Blood Lipids With Coronary Artery Plaque Among Saudi Patients Referred to Computed Tomography

BACKGROUND: Blood lipids are strong risk factor for the progression of atherosclerotic plaques. However, data on gender-specific associations are limited OBJECTIVES: To examine gender-specific associations of blood lipids with coronary plaque among in a large sample of asymptomatic Saudi patients. METHODS: Retrospective cross-sectional study was conducted among adult patients referred to (64 multidetector spiral) computed tomography (CT) for standard indications at the Prince Sultan Cardiac Centre (Riyadh, Saudi Arabia) between July 2007 and December 2017. Those with pre-existing CAD were excluded. Plaques were determined based on post-test CT angiography and coronary calcification. RESULTS: A total 2421 patients (1498 males and 923 females) were included. The prevalence of any plaque was 36.6% with higher burden in males than females (41.3% versus 28.9%, p<0.001). Approximately 78.9% of all plaques were calcified. Blood lipids (mmol/L) were 4.75±1.14 for total cholesterol, 2.90±0.96 for LDL cholesterol, 1.20±0.36 for HDL cholesterol, and 1.64±1.09 for triglycerides. Males had significantly higher triglycerides and lower HDL cholesterol compared with females. In adjusted models in males and all patients, soft and/or calcified plaques were significantly associated with lower HDL cholesterol and higher triglycerides. In females, the only significant association was between soft plaques and higher triglycerides.CONCLUSIONS: Middle-aged patients without clinical CAD in Saudi Arabia have a high burden of plaques, specially calcified ones. The findings may impact the use of lipid lowering mediations, by underscoring the importance of assessing the risk of CAD in asymptomatic patients without clinical CAD even in case of lack of coronary calcification.

Coronary artery calcium score to predict coronary CT angiography interpretability. An old problem revisited

Introduction Clinical guidelines recommend against the use of coronary computed tomography angiography (CCTA) in patients with heavy calcification due to interpretability concerns, but no specific approach or threshold is provided. Recently, alternative methods have been proposed as more reliable predictors of CCTA interpretability than the classic coronary artery calcium score (CACS). The purpose this study was to compare the performance of different measures of coronary calcification as predictors of CCTA interpretability. Methods We conducted a retrospective analysis of consecutive patients undergoing CACS and CCTA between 2018 and 2020. The key exclusion criteria were known coronary artery disease, CACS of zero, and presence of non-assessable coronary lesions for reasons other than calcification (movement/gating artifacts or vessel diameter &lt;2mm). CCTA studies were considered non-interpretable if the main reader considered one or more coronary lesions non-assessable due to calcification. Three different measures of coronary calcification were compared using ROC curve analysis: 1) total CACS; 2) CACS-to-lesion ratio (total CACS divided by the number of calcified plaques); and 3) calcium score of the most calcified plaque. Decision-tree analysis was performed to identify the algorithm that best predicts CCTA interpretability. Results A total of 432 patients (191 women, mean age 64±11 years) were included. Overall, 31 patients (7.2%) had a non-interpretable CCTA due to calcification. Patients with non-interpretable CCTA had higher CACS (median 589 vs. 50 AU, p&lt;0.001), higher CACS-to-lesion ratio (median 43 vs. 14 AU/lesion, p&lt;0.001), and higher score of the most calcified plaque (median 445 vs. 43 AU, p&lt;0.001). Among the 3 methods, CACS showed the highest discriminative power to predict a non-interpretable CCTA (C-statistic 0.93, 95% CI 0.89–0.95, p&lt;0.001) – Figure 1. Decision-tree analysis identified a single-variable algorithm (CACS value ≤515 AU) as the best discriminator of CCTA interpretability: 396 of the 409 patients (97%) with CACS ≤515 AU had an interpretable CCTA, whereas only 5 of the 23 patients (22%) with CACS &gt;515 AU had an interpretable test, yielding a total of 96% correct predictions. Conclusions The recently proposed and more complex measures of coronary calcification seem unable to outperform total CACS as a predictor of CCTA interpretability. A simple CACS cutoff-value around 500 AU remains the best discriminator for this purpose. FUNDunding Acknowledgement Type of funding sources: None. Figure 1