Calcification remodeling index assessed by cardiac CT predicts severe coronary stenosis in lesions with moderate to severe calcification

ObjectivesTo assess the diagnostic performance of the calcification remodeling index (RI) as assessed by coronary computed tomography angiography (coronary CTA) to predict the presence of severe coronary stenosis in atherosclerotic coronary lesions with moderate to severe calcification.MethodsPatients who underwent coronary CTA and invasive coronary angiography (ICA) within one month and had moderately to severely calcified lesions as revealed by coronary CTA, were retrospectively included. The calcification RI was calculated as the ratio of the cross-sectional lumen area (with inclusion of calcium area) of the most severely calcified site to the proximal reference lumen area. Other parameters, such as the calcium volume, regional Agatston score, calcification length, involved calcium arc quadrants and CTA-assessed diameter stenosis, were also recorded. A multivariate model was used to identify the variables that predict the presence of severe coronary stenosis (diameter stenosis ≧ 70%) as determined by ICA.Results422 patients with 629 lesions were finally included in the study. Lesions with severe stenoses as determined by ICA tended to have larger calcium volumes, regional Agatston scores, CTA-assessed diameter stenoses, longer calcium length, more involved calcium arc quadrants and a significantly smaller calcification remodeling index. ROC curve analysis determined the best cutoff value of the calcification RI as 0.94 (AUC = 0.816, p < 0.001), which yielded highest diagnostic accuracy (83.3%, 524/629) to identify severe coronary stenosis. Among all parameters, calcification RI ≦0.94 is the strongest independent predictor (odds ratio: 17.5, p < 0.001) of severe coronary stenosis.ConclusionsWith an optimalcut-off value of 0.94, calcification RI is the strongest independent predictor of severe coronary stenosis in calcified coronary atherosclerotic lesions.     

Is it useful to do OCTA in coronary artery disease patients to improve SYNTAX-based cardiac revascularization decision?

BackgroundTo investigate retinal and optic disk microcirculation using optical coherence tomography angiography (OCTA) in order to predict related outcomes based on the SYNergy between PCI with TAXUS and Cardiac Surgery (SYNTAX) score (SS) system in coronary artery disease patients.Methods104 patients were grouped based on coronary angiography results: 32 chronic coronary syndrome (CCS) patients, 35 acute coronary syndrome (ACS) patients, and 37 healthy controls. The SS system determined atherosclerosis degree and lesion-related mortality risk, followed by scoring as SYNTAX I score (SS-I) and SYNTAX II score (SS-II). Patients were further subdivided into SS-I, SS-II percutaneous coronary intervention (PCI), and SS-II coronary artery by-pass grafting (CABG) groups. Following a thorough ophthalmological examination, an OCTA Angio Retina mode (6 × 6 mm) automatically quantified retinal and optic disk microcirculation.ResultsThe mean ages did not differ significantly among groups (p = 0.940). The outer retinal select area varied significantly among groups, with the highest values found in ACS patients (p = 0.040). Despite non-significant differences between SS-I patients and healthy controls, the former had lower capillary plexus vessel densities in all regions and in foveal vessel density 300 μm around foveal avascular zone (FD-300) (p>0.05). Vessel densities were lowest in SS-II PCI≥28.5 patients, particularly in whole (p = 0.034) and parafoveal (p = 0.009) superficial capillary plexus, and in FD-300 (p = 0.019). Vessel densities were lowest in SS-II CABG (p = 0.020), and perifoveal (p = 0.017) deep capillary plexus, and in FD-300 (p = 0.003). The outer retina flow area increased the most in SS-II CABG≥25.1 patients (p = 0.020).ConclusionsUsing OCTA, a non-invasive imaging technique, to assess retinal and optic disk microcirculation appears to have the potential to yield significant clinical results in the early diagnosis or prognosis of cardiovascular diseases.     

Relationships between coronary calcification detected at electron beam computed tomography and percutaneous transluminal coronary angioplasty results in coronary artery disease patients

Our objective was to assess the relationship between coronary artery calcification and outcomes of percutaneous transluminal coronary angioplasty (PTCA). Electron beam computed tomography (EBCT) was performed in 80 patients with coronary artery disease (CAD) who underwent PTCA. The calcium score in each coronary artery vessel was estimated (in Agatston units) and compared with the occurrence of complications and restenosis. Angioplasty had been performed in 96 coronary artery segments with stenosis in 80 patients. The average calcium score in the unsuccessful PTCA segments was significantly higher than in ones with successful results. For complications these values were 65.0±79.9 and 27.0±44.7, respectively (p=0.02), and for restenosis 63.9±87.9 and 27.3±41.3, respectively (p=0.03). Applying receiver operating characteristics analysis we determined sensitivity and specificity of EBCT for forecasting complications and restenosis. The best cut-off value of calcium score in segment of PTCA for prediction of restenosis was 27 (sensitivity 73%, specificity 67%), and for prediction of complications 29 (sensitivity 80%, specificity 74%). Coronary segments with extensive calcification were not optimal target lesions for PTCA. Analysis of coronary calcium score should be taken into consideration during planning of endovascular coronary interventions. Electronic Publication     

Prevalence and severity of coronary artery calcium in young persons with diabetes

BackgroundCurrently, American Diabetes Association guidelines suggest statin use among persons with diabetes mellitus aged >40 years. The presence of calcified plaque in coronary arteries is a sensitive surrogate of coronary artery disease and has been shown to be an independent predictor of mortality and cardiac events.ObjectiveWe aimed to assess the prevalence and severity of calcified plaque in coronary arteries in patients aged <40 years with and without diabetes.MethodsWe included 3723 asymptomatic patients aged <40 years who had undergone coronary calcium scanning. Clinical and demographic data were collected. Agatston score was categorized into Agatston score 0 as normal, 1 to 99 as low, 100 to 399 as intermediate, and ≥400 as severe; and statistical analysis was performed.ResultsThe study population consisted of 4% persons with diabetes (n = 142) and 56% men with a mean age of 35 ± 5 years. Young persons with diabetes had greater prevalence of Agatston score > 0 than persons without diabetes (43% vs 24%; P < .0001). In addition, 12% of persons with diabetes vs 2.5% of persons without diabetes had an Agatston score ≥ 100 (P < .0001). The prevalence of calcified plaque in coronary arteries was >50% in persons with diabetes aged >35 years. After taking into account risk factors, the presence of diabetes was associated with a 4-fold higher odds of an Agatston score ≥ 100 (odds ratio, 4.19; 95% CI, 2.29–7.65; P < .0001).ConclusionOur study found that 43% of young patients with diabetes have detectable coronary atherosclerosis. Given the known clinical implications of calcified plaque in coronary arteries, future studies are needed to evaluate interventions in persons aged <40 years who exhibit subclinical atherosclerosis to reduce future cardiovascular disease events in this vulnerable population.     

Very low-dose coronary artery calcium scanning with high-pitch spiral acquisition mode: Comparison between 120-kV and 100-kV tube voltage protocols

BackgroundEffective radiation dose from a single coronary artery calcification CT scan can range from 0.8 to 10.5 mSv, depending on the protocol. Reducing the effective radiation dose to reasonable levels without affecting diagnostic image quality can result in substantial dose reduction in CT.ObjectivesWe prospectively compared tube voltages of 120 and 100 kV in a low-dose CT acquisition protocol for measuring coronary artery calcified plaque with prospectively electrocardiogram (ECG)–triggered high-pitch spiral acquisition.MethodsIn 150 consecutive patients, measurement of coronary artery calcified plaque was performed with prospectively ECG-triggered high-pitch spiral acquisition. Imaging was first done with tube voltage of 120 kV voltage and subsequently repeated with 100 kV and otherwise unchanged parameters. CT was performed with a dual-source CT system with 280 milliseconds of rotation time, 2 × 128 slices, pitch of 3.4, triggered at 60% of the R–R interval. Tube current for both protocols was set at 80 mAs. With the use of a medium sharp reconstruction kernel (Siemens B35f), cross-sectional images were reconstructed with 3.0-mm slice thickness and 1.5-mm increment. Agatston scores were determined per patient for both scan settings by 2 independent readers with the use of a standard threshold of 130 HU for calcium detection. In addition, the Agatston score was calculated with a previously proposed threshold of 147 HU for 100-kV acquisitions.ResultsMean image noise was 20 ± 5 and 27 ± 7 for 120 and 100 kV, respectively (P < 0.0001). Mean dose length product was 24 ± 6 cm · cGy for the 120-kV protocol and 14 ± 4 cm · cGy for the 100-kV protocol, corresponding to average estimated effective doses of 0.3 and 0.2 mSv (P < 0.0001). Five patients were excluded from the analysis. In the remaining 145 patients, using the standard tube voltage of 120 kV, any coronary calcium was detected in 76 identical patients by both observers. In 75 of these patients, calcium was also identified by both observers in 100-kV data sets, whereas 1 patient was scored negative by 1 reader and was assigned an Agatston score of 0.7 (threshold, 130 HU) and 0.2 (threshold, 147 HU) by the other. Interobserver disagreement for assigning a patient a zero Agatston score was the same for both scan settings (each 4 patients). The mean Agatston scores for 120-kV and 100-kV (threshold, 147 HU) scans were 105 ± 245 (range, 0–1865) and 116 ± 261 (range, 0–1917), respectively (P < 0.0001). Bland-Altman analysis indicated a systematic overestimation of the Agatston score with tube voltage of 100 kV and threshold of 147 HU (mean difference, 11; 95% limits of agreement, 62 to -40). Similar results were observed for coronary calcium volume scores.ConclusionHigh-pitch spiral acquisition allows coronary calcium scoring with effective doses below 0.5 mSv. The use of 100-kV tube voltage further reduces effective radiation dose compared with the standard of 120 kV; however, it leads to significant overestimation of the Agatston score when the standard threshold of 130 HU is used. Adjusting the threshold to 147 HU leads to a better agreement compared with standard 120 kV protocols yet with a remaining systematic bias toward overestimation of the Agatston score. For high-pitch spiral acquisition mode, effective radiation dose reduction when using a 100-kV setting is minimal compared with the standard 120-kV setting and may be considered nonsignificant in a clinical setting.     

Detection of small coronary calcifications in patients with Agatston coronary artery calcium score of zero

BackgroundA coronary artery calcium score (CACS) of 0 is associated with a very low risk of cardiac event. However, the Agatston CACS may fail to detect very small or less dense calcifications. We investigated if an alteration of the Agatston criteria would affect the ability to detect such plaques.MethodsWe evaluated 322 patients, 161 who had a baseline scan with CACS ?= ?0 and a follow-up scan with CACS>0 and 161 with two serial CACS ?= ?0 scans (control group), to identify subtle calcification not detected in the baseline scan because it was not meeting the Agatston size and HU thresholds (≥1 ?mm² and ≥130HU). Size threshold was set to <1 ?mm² and the HU threshold modified in a stepwise manner to 120, 110, 100 and 90. New lesions were classified as true positive or false positive(noise) using the follow-up scan.ResultsWe identified 69 visually suspected subtle calcified lesions in 65/322 (20.2%) patients with CAC ?= ?0 by the Agatston criteria. When size threshold was set as <1 ?mm² and HU ?≥ ?130, 36 lesions scored CACS>0, 34 (94.4%) true positive and 2 (5.6%) false positive. When decrease in HU (120HU, 110HU, 100HU, and 90HU) threshold was added to the reduced size threshold, the number of lesions scoring>0 increased (46, 55, 59, and 69, respectively) at a cost of increased false positive rate (8.7%, 20%, 22%, and 30.4% respectively). Eliminating size or both size and HU threshold to ≥120HU correctly reclassified 9.6% and 12.1% of patients respectively.ConclusionEliminating size and reducing HU thresholds to ≥120HU improved the detection of subtle calcification when compared to the Agatston CACS method.     

Fully Automatic Coronary Calcium Score Software Empowered by Artificial Intelligence Technology: Validation Study Using Three CT Cohorts

ObjectiveThis study aimed to validate a deep learning-based fully automatic calcium scoring (coronary artery calcium [CAC]_auto) system using previously published cardiac computed tomography (CT) cohort data with the manually segmented coronary calcium scoring (CAC_hand) system as the reference standard.Materials and MethodsWe developed the CAC_auto system using 100 co-registered, non-enhanced and contrast-enhanced CT scans. For the validation of the CAC_auto system, three previously published CT cohorts (n = 2985) were chosen to represent different clinical scenarios (i.e., 2647 asymptomatic, 220 symptomatic, 118 valve disease) and four CT models. The performance of the CAC_auto system in detecting coronary calcium was determined. The reliability of the system in measuring the Agatston score as compared with CAC_hand was also evaluated per vessel and per patient using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. The agreement between CAC_auto and CAC_hand based on the cardiovascular risk stratification categories (Agatston score: 0, 1–10, 11–100, 101–400, > 400) was evaluated.ResultsIn 2985 patients, 6218 coronary calcium lesions were identified using CAC_hand. The per-lesion sensitivity and false-positive rate of the CAC_auto system in detecting coronary calcium were 93.3% (5800 of 6218) and 0.11 false-positive lesions per patient, respectively. The CAC_auto system, in measuring the Agatston score, yielded ICCs of 0.99 for all the vessels (left main 0.91, left anterior descending 0.99, left circumflex 0.96, right coronary 0.99). The limits of agreement between CAC_auto and CAC_hand were 1.6 ± 52.2. The linearly weighted kappa value for the Agatston score categorization was 0.94. The main causes of false-positive results were image noise (29.1%, 97/333 lesions), aortic wall calcification (25.5%, 85/333 lesions), and pericardial calcification (24.3%, 81/333 lesions).ConclusionThe atlas-based CAC_auto empowered by deep learning provided accurate calcium score measurement as compared with manual method and risk category classification, which could potentially streamline CAC imaging workflows.     

Coronary CT Calcium Score in Patients With Prior Nongated CT,Is it Necessary?

PurposeTo evaluate the percentage of patients undergoing gated coronary artery calcium score CTs that had a prior nongated chest CT. To assess the accuracy of prior nongated chest CTs in the detection of coronary calcium.BackgroundCardiovascular disease is the most common cause of death worldwide. Quantifying coronary artery calcification on gated calcium score CT has proven to be strongly predictive of adverse coronary artery disease events. However, visual estimation and ordinal scoring on nongated chest CTs is predictive of coronary calcium burden.MethodsConsecutive gated calcium score CTs at a single institution from 10/2014 to 10/2016 were retrospectively evaluated with IRB approval/waiver of informed consent. The presence or absence of coronary calcium and ordinal score on nongated chest CT was compared to Agatston score on gated calcium score CT.ResultsForty-two of 441 patients (9.5%) with a gated calcium score had a prior nongated chest CT, with a mean time difference of 810 days. Of the 42 prior chest CTs, 69% had coronary artery calcium (CAC) and 31% did not, with 100% predictive accuracy for the presence or absence of CAC on subsequent gated calcium score CTs. There was 86% correlation of Agatston score on gated calcium score CT with ordinal score on the prior chest CT. Ordinal score divided into independent groups of severity was related to increased severity of Agatston score on the gated calcium score CT (P< 0.001). A majority of prior chest CT studies with coronary calcium failed to include this information in the final report.ConclusionsA large percentage of gated calcium score CTs were performed despite a prior chest CT. The ordinal score on chest CTs correlated with Agatston score on gated calcium score CTs. The presence of CAC on chest CTs was underreported in a majority of cases.     

Cumulative exposure amount of PM2.5 in the ambient air is associated with coronary atherosclerosis - Serial coronary CT angiography study

BackgroundWe investigated the change of coronary atherosclerosis with long-term exposure to fine particulate matter of aerodynamic diameter <2.5 ?μm (PM_2.5) using coronary computed tomography angiography (CCTA).MethodsSubjects undergoing serial CCTAs between January 2007 and December 2017 (n ?= ?3,127) were analyzed. Each individual's cumulative amount of PM_2.5 exposure between the two CCTAs was evaluated by Kriging interpolation and zonal analysis, considering the time interval between the two CCTAs. The main outcome was progression of coronary artery calcium (CAC) with additional semiquantitative analysis on the changes in the severity and composition of atherosclerotic plaques.ResultsThe CAC scores increased by 30.8 Agatston units per-year under a median PM_2.5 concentration 24.9 ?μg/m³ and tended to increase with the cumulative amount of PM_2.5 exposure (r ?= ?0.321, p ?<0.001). The CAC progressed in 1,361 (43.5%) subjects during a median 53 months follow-up. The cumulative amount of PM_2.5 exposure was independently associated with CAC progression (adjusted OR 1.09, p ?<0.001). By random forest analysis, the relative impact of cumulative amount of PM_2.5 exposure on CAC progression was higher than that of traditional cardiovascular risk factors and the average concentration of PM_2.5. The extent of coronary atherosclerosis and newly developed calcified plaque on follow-up were also significantly associated with the cumulative amount of PM_2.5 exposure.ConclusionsCumulative exposure to air pollution is associated with the progression of diffuse coronary calcification, the importance of which may be more significant than other traditional cardiovascular risk factors. Further investigations into the causality between PM_2.5 and coronary atherosclerosis are warranted to improve global cardiovascular health.     

Favorable preservation of erectile function after prostate brachytherapy for localized prostate cancer

PurposeWe analyzed the rate of preserved potency after prostate brachytherapy (PB) with radioactive seeds and the impact of patient comorbidities on post-PB erectile dysfunction (ED).MethodsWe included 627 patients who were assessed for pre- and postimplant potency between 2005 and 2017. Assessment was based on the Common Terminology Criteria for Adverse Events Scale (CTCAEs). Logistic regression models were used to assess clinical predictors of preserved potency after PB defined as having sufficient erections for sexual activity with or without the need of oral pharmacologic assistance. Covariates included age, diabetes (DM), hypertension (HTN), dyslipidemia (DLP), coronary artery disease (CAD), International Prostate Symptom Score (IPSS), prostate volume, and Cancer of the Prostate Risk Assessments (CAPRA) score. Patients on androgen deprivation therapy or using five alpha reductase inhibitors were excluded from analyses.ResultsPost-PB potency was assessed at an average of 6 months (n = 627), 1 year (n = 538), 2 years (=440), 4 years (n = 272), and 5 years (n = 124). At 2 and 5 years, post-PB potency was preserved in 87% and 84% of patients, respectively. When adjusting for all available covariates, advanced age, pre-PB potency, and the presence of vascular comorbidities (HTN, DM, and DLP) were all predictors of potency at 2 years after PB (all p < 0.01). When performing a sensitivity analysis for vascular comorbidities, the presence of DM had the strongest impact on ED than either HTN or DLP (p < 0.01).ConclusionMore than 84% of patients had preserved potency 5 years after PB. Advanced age, pre-PB potency, and vascular comorbidities had a statistically significant impact on potency after PB.     

Low-kV coronary artery calcium scoring with tin filtration using a kV-independent reconstruction algorithm

PurposeTo investigate the accuracy of Agatston scoring and potential for radiation dose reduction of a coronary artery calcium scoring (CACS) CT protocol at 100 kV with tin filtration (Sn100kV) and kV-independent iterative reconstruction, compared to standard 120 kV acquisitions.Materials and methodsWith IRB approval and in HIPAA compliance, 114 patients (61.8 ± 9.6 years; 66 men) underwent CACS using a standard 120 kV protocol and an additional Sn100kV CACS scan. The two datasets were reconstructed using a medium sharp convolution algorithm and in addition the Sn100kV scans were reconstructed iteratively based on a kV-independent algorithm. Agatston scores and radiation dose values were compared between the Sn100kV and the standard 120 kV protocol.ResultsMedian Agatston scores derived from the Sn100kV protocol with the kV-independent algorithm and the standard 120 kV were 21.4 (IQR, 0–173.8) and 24.7 (IQR, 0–171.1) respectively, with no significant differences (p=0.18). Agatston scores derived from the two different protocols had an excellent correlation (r = 0.99). The dose-length-product was 11.5 ± 4.1 mGy × cm using Sn100kV and 50.4 ± 24.9 mGy × cm using the standard 120 kV protocol (p < 0.01), resulting in a significantly lower (77%) effective dose at Sn100kV (0.16 ± 0.06 mSv vs. 0.71 ± 0.35 mSv, p < 0.01). Additionally, 99% of the patients were classified into the same risk category (0, 1–10, 11–100, 101–400, or >400) using the Sn100kV protocol.ConclusionCACS at Sn100kV using the kV-independent iterative algorithm is feasible and provides high accuracy when compared to standard 120 kV scanning. Furthermore, radiation dose can be significantly reduced for this screening application in a priori healthy individuals.     

A comparison of outcomes with coronary artery calcium scanning in unselected populations: The Multi-Ethnic Study of Atherosclerosis (MESA) and Heinz Nixdorf RECALL study (HNR)

BackgroundThe Multi-Ethnic Study of Atherosclerosis (MESA) and the Heinz Nixdorf RECALL (Risk factors, Evaluation of Coronary Calcium and Lifestyle Factors) study (HNR) differed in regard to informing physicians and patients of the results of their subclinical atherosclerosis.ObjectiveThis study investigates whether the association of the presence of coronary calcium with incident nonfatal and fatal cardiovascular events is different among these 2 large, population-based observational studies.MethodsAll white subjects aged 45 to 75 years, free of baseline cardiovascular disease were included (n = 2232 in MESA; n = 3119 HNR participants). We studied the association between coronary calcium and event rates at 5 years, including hard cardiac events (myocardial infarction, cardiac death, resuscitated cardiac arrest), and separately added revascularizations and strokes (fatal and nonfatal) to determine adjusted hazard ratios.ResultsBoth cohorts showed low coronary heart disease (including revascularization) rates with zero coronary calcium (1.13% and 1.16% over 5 years in MESA and HNR, respectively) and increasing significantly in both groups with Agatston score 100 to 399 (6.71% and 4.52% in MESA and HNR, respectively) and Agatston score > 400 (12.5% and 13.54% in MESA and HNR, respectively) and showing strong independent predictive values for Agatston scores of 100 to 399 and >400, despite multivariable adjustment for risk factors. Risk factor-adjusted 5-year revascularization rates were nearly identical for HNR and MESA and were generally low for both studies (1.4% [45 of 3119] for HNR and 1.9% [43 of 2232] for MESA) over 5 years.ConclusionsAcross 2 culturally diverse populations, Agatston score >400 is a strong predictor of events. High Agatston score did not statistically result in revascularization, and knowledge of the presence of coronary calcium did not increase revascularizations.     

CT coronary calcium scoring with tin filtration using iterative beam-hardening calcium correction reconstruction

ObjectivesTo investigate the diagnostic accuracy of CT coronary artery calcium scoring (CACS) with tin pre-filtration (Sn100 kVp) using iterative beam-hardening correction (IBHC) calcium material reconstruction compared to the standard 120 kVp acquisition.BackgroundThird generation dual-source CT (DSCT) CACS with Sn100 kVp acquisition allows significant dose reduction. However, the Sn100 kVp spectrum is harder with lower contrast compared to 120kVp, resulting in lower calcium score values. Sn100 kVp spectral correction using IBHC-based calcium material reconstruction may restore comparable calcium values.MethodsImage data of 62 patients (56% male, age 63.9 ± 9.2years) who underwent a clinically-indicated CACS acquisition using the standard 120 kVp protocol and an additional Sn100 kVp CACS scan as part of a research study were retrospectively analyzed. Datasets of the Sn100 kVp scans were reconstructed using a dedicated spectral IBHC CACS reconstruction to restore the spectral response of 120 kVp spectra. Agatston scores were derived from 120 kVp and IBHC reconstructed Sn100 kVp studies. Pearson’s correlation coefficient was assessed and Agatston score categories and percentile-based risk categorization were compared.ResultsMedian Agatston scores derived from IBHC Sn100 kVp scans and 120 kVp acquisition were 31.7 and 34.1, respectively (p = 0.057). Pearson‘s correlation coefficient showed excellent correlation between the acquisitions (r = 0.99, p < 0.0001). Agatston score categories and percentile-based cardiac risk categories showed excellent agreement (ĸ = 1.00 and ĸ = 0.99), resulting in a low cardiac risk reclassification of 1.6% with the use of IBHC CACS reconstruction. Image noise was 24.9 ± 3.6HU in IBHC Sn100 kVp and 17.1 ± 3.9HU in 120 kVp scans (p < 0.0001). The dose-length-product was 13.2 ± 3.4 mGy cm with IBHC Sn100 kVp and 59.1 ± 22.9 mGy cm with 120 kVp scans (p < 0.0001), resulting in a significantly lower effective radiation dose (0.19 ± 0.07 mSv vs. 0.83 ± 0.33 mSv, p < 0.0001) for IBHC Sn100 kVp scans.ConclusionLow voltage CACS with tin filtration using a dedicated IBHC CACS material reconstruction algorithm shows excellent correlation and agreement with the standard 120 kVp acquisition regarding Agatston score and cardiac risk categorization, while radiation dose is significantly reduced by 75% to the level of a chest x-ray.     

Coronary calcium scanning independently detects coronary artery disease in asymptomatic firefighters: A prospective study

BackgroundSudden cardiac death is the leading cause of death among firefighters in the United States. Fire departments commonly maintain physical examination protocols, often with exercise stress testing, to detect risk of coronary heart disease.ObjectiveWe sought to determine whether coronary calcium detected by electron beam computed tomography (EBCT) adds incremental risk stratification beyond the traditional risk factors in asymptomatic community-based firefighters.MethodsThree hundred ninety nine asymptomatic firefighters underwent a coronary calcium scan on a GE/Imatron C-150 Ultrafast EBCT scanner, using standardized imaging protocols. Framingham risk factor data were obtained on each patient by using a questionnaire. Agatston scores were derived and compared with national database of Agatston scores for asymptomatic populations on the basis of age and sex, allowing determination of a calcium percentile for each score.ResultsCoronary calcium was found only in men >34 years of age. Of the 53% who had positive scans (Agatston score > 0), 87% had higher than average Agatston scores compared with a national database (P < 0.01). Agatston score above the 75th percentile was found in 57% of firefighters. No correlation was observed between traditional risk factors and those with and without coronary calcium.ConclusionsFirefighters have a high burden of calcified coronary atherosclerosis, greater than anticipated on the basis of age and coronary risk factors.     

Extent and severity of coronary artery disease by coronary CT angiography is associated with elevated left ventricular diastolic pressures and worsening diastolic function

BackgroundPatients with flow-limiting coronary stenoses exhibit elevated left ventricular end-diastolic pressure (LVEDP) and abnormal left ventricular (LV) relaxation.ObjectiveWe investigated the relationship of extent and severity of coronary artery disease (CAD) by coronary CT angiography (CTA) to LVEDP and measures of LV diastolic dysfunction.MethodsWe identified consecutive patients undergoing coronary CTA and transthoracic echocardiography who were assessed for diastolic function. CAD was evaluated on a per-patient, per-vessel, and per-segment basis for intraluminal diameter stenosis by using an 18-segment model (0 = none, 1 = 1%–49%, 2 = 50%–69%, and 3 = 70%–100%) and summed over segments to obtain overall coronary plaque burden (segment stenosis score [SSS]; maximum = 54). Transthoracic echocardiography evaluated mitral inflow E wave-to-A wave ratio, tissue Doppler early mitral annual tissue velocity axial excursion, stage of diastolic dysfunction, and LV dimensions and estimated LVEDP from the ratio of mitral inflow velocity to early mitral annular (medial) tissue velocity.ResultsFour hundred seventy-eight patients (57% women; mean age, 57.9 ± 14.6 years; 24.9% prior CAD) comprised the study population. Increasing per-patient maximal coronary stenosis, number of vessels with obstructive stenosis, and SSS were associated with increased LVEDP. The prevalence of advanced diastolic dysfunction increased with greater number of obstructive vessels. In multivariable analyses, SSS was associated with increased LVEDP (0.8 mm Hg per tertile increase in SSS, 0.5–1.1; P < .001); reduced E′ axial excursion (?0.3; 95% confidence interval [CI], ?0.5 to ?0.1; P = .001), increased LV mass index (1.6 g/m² per tertile increase in SSS; P = .04), and increased relative wall thickness (0.005; 95% CI, 0.004–0.009; P = .03), with consistent relationships persisting even among persons with per-patient maximal stenosis <50% and LV ejection fraction ≥55%.ConclusionsExtent and severity of obstructive as well as nonobstructive CAD by coronary CTA are associated with increased LVEDP and measures of diastolic dysfunction.     

Sex- and age-related differences of myocardial perfusion at rest assessed with multidetector computed tomography

BackgroundThe clinical presentation of ischemic heart disease in women differs from men, which could reflect sex-related differences of normal physiology. Cardiac CT angiography provides a noninvasive method to assess both regional and transmural myocardial perfusion in addition to coronary atherosclerosis.ObjectiveThe aim of this study was to evaluate potential sex-related differences of (1) left ventricular (LV) myocardial perfusion measured as LV myocardial attenuation density/LV blood pool attenuation density (Myo_AD-ratio) at rest and (2) transmural perfusion ratio (TPR) as a measure of endocardial perfusion relative to epicardial perfusion.MethodsMyocardial perfusion at rest and coronary artery atherosclerosis were evaluated with multidetector CT in 206 asymptomatic women and 203 age-matched men from the Copenhagen General Population Study.ResultsLV myocardial perfusion at rest (LV Myo_AD-ratio) was higher in women than in men (9% difference; P = 0.039). In a multivariable analysis, including age, sex, cardiovascular risk factors, Agatston score, and presence of coronary stenosis, global LV Myo_AD-ratio remained significantly higher in women than in men (P = 0.045). No effect of cardiovascular risk factors on myocardial perfusion at rest was noted. Myocardial perfusion at rest was correlated to age in men (r = 0.15, P = 0.031) but not in women (r = ?0.01, P = 0.83). TPR was slightly lower in women than in men (1.12 vs 1.14; P = 0.0019).ConclusionLV myocardial perfusion at rest is higher in women than men independent of coronary atherosclerosis in asymptomatic subjects with risk factors.     

Accurate Measurement of Agatston Score Using kVp-Independent Reconstruction Algorithm for Ultra-High-Pitch Sn150 kVp CT

ObjectiveTo investigate the accuracy of the Agatston score obtained with the ultra-high-pitch (UHP) acquisition mode using tin-filter spectral shaping (Sn150 kVp) and a kVp-independent reconstruction algorithm to reduce the radiation dose.Materials and MethodsThis prospective study included 114 patients (mean ± standard deviation, 60.3 ± 9.8 years; 74 male) who underwent a standard 120 kVp scan and an additional UHP Sn150 kVp scan for coronary artery calcification scoring (CACS). These two datasets were reconstructed using a standard reconstruction algorithm (120 kVp + Qr36d, protocol A; Sn150 kVp + Qr36d, protocol B). In addition, the Sn150 kVp dataset was reconstructed using a kVp-independent reconstruction algorithm (Sn150 kVp + Sa36d, protocol C). The Agatston scores for protocols A and B, as well as protocols A and C, were compared. The agreement between the scores was assessed using the intraclass correlation coefficient (ICC) and the Bland–Altman plot. The radiation doses for the 120 kVp and UHP Sn150 kVp acquisition modes were also compared.ResultsNo significant difference was observed in the Agatston score for protocols A (median, 63.05; interquartile range [IQR], 0–232.28) and C (median, 60.25; IQR, 0–195.20) (p = 0.060). The mean difference in the Agatston score for protocols A and C was relatively small (−7.82) and with the limits of agreement from −65.20 to 49.56 (ICC = 0.997). The Agatston score for protocol B (median, 34.85; IQR, 0–120.73) was significantly underestimated compared with that for protocol A (p < 0.001). The UHP Sn150 kVp mode facilitated an effective radiation dose reduction by approximately 30% (0.58 vs. 0.82 mSv, p < 0.001) from that associated with the standard 120 kVp mode.ConclusionThe Agatston scores for CACS with the UHP Sn150 kVp mode with a kVp-independent reconstruction algorithm and the standard 120 kVp demonstrated excellent agreement with a small mean difference and narrow agreement limits. The UHP Sn150 kVp mode allowed a significant reduction in the radiation dose.     

Detection and quantification of coronary artery calcification with electron-beam and conventional CT

To identify patients with increased risk of having coronary artery disease (CAD), electron-beam computed tomography (EBCT) was used for years for quantifying calcifications of the coronary arteries. The first direct comparison between EBCT and conventional CT was performed to determine the reliability of widely available conventional CT for the assessment of the coronary calcium score. Fifty male patients with suspected CAD were investigated with both modalities, EBCT and conventional 500-ms non-spiral partial scan CT. Scoring of the coronary calcification was performed according to the Agatston method. Forty-two of these patients underwent coronary angiography for the assessment of significant luminal narrowing. The correlation coefficient of the score values of both modalities was highly significant (r = 0.982, p < 0.001). The variability between the two modalities was 42 %. Mean calcium score in patients with significant coronary luminal narrowing (n = 37) was 1104 ± 1089 with EBCT and 1229 ± 1327 with conventional CT. In patients without luminal narrowing (n = 5) mean calcium score was 73 ± 57 with EBCT and 26 ± 35 with conventional CT. Although images of the heart from conventional CT may suffer from cardiac motion artifacts, conventional CT has the potential to identify patients with CAD with accuracy similar to EBCT. Received: 13 July 1998; Revision received: 11 October 1998; Accepted: 14 October 1998     

Utility of visual coronary artery calcification on non-cardiac gated thoracic CT in predicting clinical severity and outcome in COVID-19

BackgroundAssessment of visual-coronary artery calcification on non-cardiac gated CT in COVID-19 patients could provide an objective approach to rapidly identify and triage clinically severe patients for early hospital admission to avert worse prognosis.PurposeTo ascertain the role of semi-quantitative scoring in visual-coronary artery calcification score (V-CACS) for predicting the clinical severity and outcome in patients with COVID-19.Materials and methodsWith institutional review board approval this study included 67 COVID-19 confirmed patients who underwent non-cardiac gated CT chest in an inpatient setting. Two blinded radiologist (Radiologist-1 &2) assessed the V-CACS, CT Chest severity score (CT-SS). The clinical data including the requirement for oxygen support, assisted ventilation, ICU admission and outcome was assessed, and patients were clinically subdivided depending on clinical severity. Logistic regression analyses were performed to identify independent predictors. ROC curves analysis is performed for the assessment of performance and Pearson correlation were performed to looks for the associations.ResultsV-CACS cut off value of 3 (82.67% sensitivity and 54.55% specificity; AUC 0.75) and CT-SS with a cut off value of 21.5 (95.7% sensitivity and 63.6% specificity; AUC 0.87) are independent predictors for clinical severity and also the need for ICU admission or assisted ventilation. The pooling of both CT-SS and V-CACS (82.67% sensitivity and 86.4% specificity; AUC 0.92) are more reliable in terms of predicting the primary outcome of COVID-19 patients. On regression analysis, V-CACS and CT-SS are individual independent predictors of clinical severity in COVID-19 (Odds ratio, 1.72; 95% CI, 0.99–2.98; p = 0.05 and Odds ratio, 1.22; 95% CI, 1.08–1.39; p = 0.001 respectively). The area under the curve (AUC) for pooled V-CACS and CT-SS was 0.96 (95% CI 0.84–0.98) which correctly predicted 82.1% cases.ConclusionLogistic regression model using pooled Visual-Coronary artery calcification score and CT Chest severity score in non-cardiac gated CT can predict clinical severity and outcome in patients with COVID-19.     

Sex- and age-specific differences in the long-term prognostic value of morphological plaque features detected by coronary computed tomography angiography

BackgroundAlthough sex- and age-specific differences in coronary plaque features detected by coronary computed tomography angiography (CCTA) are known, insufficient information regarding the long-term prognostic value of these findings exists.MethodsA total of 1615 patients with suspected but not previously diagnosed coronary artery disease (CAD) were examined by CCTA and coronary plaque features were assessed. The median follow-up period was 10.5 (IQR 9.2–11.4) years. Cox proportional-hazards analysis was used for the combined endpoint of cardiac death or nonfatal myocardial infarction.ResultsThe endpoint occurred more often in patients older than 65 years (5.66% vs. 2.05%; p = 0.00029) but similarly between female (3.34%) and male (3.07%) patients (p = 0.76). Both sexes displayed a similar prevalence for noncalcified (female vs. male: 0.77 ± 1.38 vs. 0.89 ± 1.41; p = 0.098) and low-attenuation (female vs. male: 2.6% vs. 4.37%; p = 0.096) plaques. As assessed by p for interaction CADRADS (p for interaction = 0.013), noncalcified plaques (p for interaction = 0.022) and low-attenuation plaques (p for interaction = 0.045) had a better primary endpoint association in women than in men. Concerning age, no difference in outcome association was apparent as evaluated by p for interaction.ConclusionCCTA demonstrates excellent long-term prognostic value irrespective of sex and age and independent from the higher prevalence of atherosclerotic plaques in men and patients older than 65 years. Although similarly prevalent in both sexes, noncalcified and low-attenuation plaques exhibit a better prognostic value in women.