Reduced Axial Scan Length Coronary Calcium Scoring Reduces Radiation Dose and Provides Adequate Clinical Decision-Making Before Coronary CT Angiography (original) (raw)
Related papers
International Journal of Cardiovascular Imaging
The correlation between formal coronary artery calcium scoring (CACS) determined by multi-detector CT (MDCT) and the presence of coronary calcium on standard non-gated CT chest examinations was evaluated. In 163 consecutive healthy participants, we performed screening same-day standard non-gated, non-enhanced CT chest exams followed by high-resolution, ECG-synchronized MDCT exams for CACS. For the standard CT examinations, a scoring system (Weston score, range 0–12) was developed assigning a score (0–3) for each coronary vessel including the left main trunk. Overall, 30% and 39% of patients had CAC on standard CT and MDCT exams, respectively (P = 0.13). CAC on standard CT was highly correlated to the Agatston CACS on the MDCT (Spearman correlation coefficient 0.83, P < 0.001). Absence of calcium on the standard CT exam was associated with a very low CACS (mean Agatston 0.5, range 0–19). A Weston score >2 identified a CACS > 100 with an area under the curve of 0.976, sensitivity of 100%, and specificity of 85%. A Weston score >7 identified a CACS > 400 with an area under the curve of 0.991, sensitivity of 100%, specificity of 98%. The intra-observer variability was low as was the inter-observer variability between a cardiac specialized radiologist and a non-specialized reader. A visual coronary artery scoring system on standard, non-gated CT correlates well with traditional methods for CACS. Further, a non-expert cardiac radiologist performed equally well to a cardiac expert. This information suggests that a visual scoring system, at least in a descriptive manner can be utilized for a general statement about coronary artery calcification seen on standard CT imaging to guide clinicians in risk stratification.
Heart, Lung and Circulation, 2013
A high coronary calcium burden may adversely affect image quality of CT coronary angiography (CTCA). The ability to rule out clinically significant disease in this setting is uncertain. We examined CTCA findings in patients with a calcium score of &amp;amp;amp;amp;amp;amp;amp;gt;600. Utilising a search of death notices, structured patient interview and medical records, downstream investigations, cardiovascular events, revascularisation and mortality were recorded. Sixty patients with a calcium score &amp;amp;amp;amp;amp;amp;amp;gt;600 had CTCA performed on the same day. Coronary disease findings were: mild 28%, moderate 33%, severe 32% and non-diagnostic 7%. During a median 1.75-year follow-up, 31 (53%) of patients underwent further assessment for coronary disease, eight patients (13%) underwent revascularisation and there were two non-cardiovascular and one cardiovascular deaths. No patient with mild or moderate disease at CTCA had subsequently demonstrated ischaemia, was deemed to require PCI or suffered cardiac mortality. The negative predictive value of CTCA for subsequent PCI and all-cause mortality was 97% (100% for cardiac mortality only). The positive predictive value of CTCA for revascularisation or CV death was 42%. In patients with an elevated coronary calcium score, a negative CTCA implies an excellent short-term outcome and appears to exclude clinically significant coronary disease.
Journal of Thoracic Imaging
The Society of Cardiovascular Computed Tomography (SCCT) and the Society of Thoracic Radiology (STR) have jointly produced this document. Experts in this subject have been selected from both organizations to examine subject-specific data and write this guideline in partnership. A formal literature review, weighing the strength of evidence has been performed. When available, information from studies on cost was considered. Computed tomography (CT) acquisition, CAC scoring methodologies and clinical outcomes are the primary basis for the recommendations in this guideline. This guideline is intended to assist healthcare providers in clinical decision making. The recommendations reflect a consensus after a thorough review of the best available current scientific evidence and practice patterns of experts in the field and are intended to improve patient care while acknowledging that situations arise where additional information may be needed to better inform patient care.
Plos One, 2014
Aims: To investigate the value of coronary calcium scoring (CCS) as a filter scan prior to coronary computed tomography angiography (CCTA). Methods and Results: Between February 2008 and April 2011, 732 consecutive patients underwent clinically indicated CCTA. During this 'control phase', CCS was performed in all patients. In patients with CCS$800, CCTA was not performed. During a subsequent 'CCTA phase' (May 2011-May 2012) another 200 consecutive patients underwent CCTA, and CCS was performed only in patients with increased probability for severe calcification according to age, gender and atherogenic risk factors. In patients where CCS was not performed, calcium scoring was performed in contrast-enhanced CCTA images. Significant associations were noted between CCS and age (r = 0.30, p,0.001) and coronary risk factors (x 2 = 37.9; HR = 2.2; 95%CI = 1.7-2.9, p,0.001). Based on these associations, a #3% pre-test probability for CCS$800 was observed for males ,61 yrs. and females ,79 yrs. According to these criteria, CCS was not performed in 106 of 200 (53%) patients during the 'CCTA phase', including 47 (42%) males and 59 (67%) females. This resulted in absolute radiation saving of ,1 mSv in 75% of patients younger than 60 yrs. Of 106 patients where CCS was not performed, estimated calcium scoring was indeed ,800 in 101 (95%) cases. Non-diagnostic image quality due to calcification was similar between the 'control phase' and the 'CCTA' group (0.25% versus 0.40%, p = NS). Conclusion: The value of CCS as a filter for identification of a high calcium score is limited in younger patients with intermediate risk profile. Omitting CCS in such patients can contribute to further dose reduction with cardiac CT studies.
European Radiology, 2009
To evaluate the diagnostic accuracy of 64-slice CT coronary angiography (CT-CA) for the detection of significant coronary artery stenosis in patients with zero on the Agatston Calcium Score (CACS). We enrolled 279 consecutive patients (96 male, mean age 48±12 years) with suspected coronary artery disease. Patients were symptomatic (n=208) or asymptomatic (n=71), and underwent conventional coronary angiography (CAG). For CT-CA we administered an IV bolus of 100 ml of iodinated contrast material. CT-CA was compared to CAG using a threshold for significant stenosis of ≥50%. The prevalence of disease demonstrated at CAG was 15% (1.4% in asymptomatic). The population at CAG showed no or non-significant disease in 85% (238/279), single vessel disease in 9% (25/279), and multi-vessel disease in 6% (16/279). Sensitivity, specificity, and positive and negative predictive values of CT-CA vs. CAG on the patient level were 100%, 95%, 76%, and 100% in the overall population and 100%, 100%, 100%, and 100% in asymptomatic patients, respectively. CT-CA proves high diagnostic performance in patients with or without symptoms and with zero CACS. The prevalence of significant disease detected by CT-CA was not negligible in asymptomatic patients. The role of CT-CA in asymptomatic patients remains uncertain.
European Radiology, 2009
We sought to investigate the performance of 64-slice CT in symptomatic patients with different coronary calcium scores. Two hundred patients undergoing 64-slice CT coronary angiography for suspected coronary artery disease were enrolled into five groups based on Agatston calcium score using the Mayo Clinic risk stratification: group 1: score 0, group 2: score 1–10, group 3: score 11–100, group 4: score 101–400, and group 5: score > 401. Diagnostic accuracy for the detection of significant (≥50% lumen reduction) coronary artery stenosis was assessed on a per-segment and per-patient base using quantitative coronary angiography as the gold standard. For groups 1 through 5, sensitivity was 97, 96, 91, 90, 92%, and specificity was 99, 98, 96, 88, 90%, respectively, on a per-segment basis. On a per-patient basis, the best diagnostic performance was obtained in group 1 (sensitivity 100% and specificity 100%) and group 5 (sensitivity 95% and specificity 100%). Progressively higher coronary calcium levels affect diagnostic accuracy of CT coronary angiography, decreasing sensitivity and specificity on a per-segment base. On a per-patient base, the best results in terms of diagnostic accuracy were obtained in the populations with very low and very high cardiovascular risk.
The American Journal of Cardiology, 2010
The purpose of the present study was to assess the impact of clinical presentation and pretest likelihood on the relation between coronary calcium score (CCS) and computed tomographic coronary angiography (CTA) to determine the role of CCS as a gatekeeper to CTA in patients presenting with chest pain. In 576 patients with suspected coronary artery disease (CAD), CCS and CTA were performed. CCS was categorized as 0, 1 to 400, and >400. On CT angiogram the presence of significant CAD (>50% luminal narrowing) was determined. Significant CAD was observed in 14 of 242 patients (5.8%) with CCS 0, in 94 of 260 patients (36.2%) with CCS 1 to 400, and in 60 of 74 patients (81.1%) with CCS >400. In patients with CCS 0, prevalence of significant CAD increased from 3.9% to 4.1% and 14.3% in nonanginal, atypical, and typical chest pain, respectively, and from 3.4% to 3.9% and 27.3% with a low, intermediate, and high pretest likelihood, respectively. In patients with CCS 1 to 400, prevalence of significant CAD increased from 27.4% to 34.7% and 51.7% in nonanginal, atypical, and typical chest pain, respectively, and from 15.4% to 35.6% and 50% in low, intermediate, and high pretest likelihood, respectively. In patients with CCS >400, prevalence of significant CAD on CT angiogram remained high (>72%) regardless of clinical presentation and pretest likelihood. In conclusion, the relation between CCS and CTA is influenced by clinical presentation and pretest likelihood. These factors should be taken into account when using CCS as a gatekeeper for CTA.
Texas Heart Institute Journal, 2022
Computed tomographic coronary artery calcium scanning enables cardiovascular risk stratification; however, exposing patients to high radiation levels is an ongoing concern. New-generation computed tomographic systems use lower radiation doses than older systems do. To quantify comparative doses of radiation exposure, we prospectively acquired images from 220 patients with use of a 64-slice GE LightSpeed VCT scanner (control group, n=110) and a 256-slice GE Revolution scanner (study group, n=110). The groups were matched for age, sex, and body mass index; statistical analysis included t tests and linear regression. The mean dose-length product was 21% lower in the study group than in the control group (60.2 ± 27 vs 75.9 ± 22.6 mGy·cm; P <0.001) and also in each body mass index subgroup. Similarly, the mean effective radiation dose was 21% lower in the study group (0.84 ± 0.38 vs 1.06 ± 0.32 mSv) and lower in each weight subgroup. After adjustment for sex, women in the study group ...