Non-diagnostic coronary artery calcification and stenosis: a correlation of coronary computed tomography angiography and invasive coronary angiography.

Background Heavy coronary artery calcification (CAC) impairs diagnostic accuracy of coronary computed tomography angiography (cCTA) and is considered to be a major limitation. Purpose To investigate the effect of non-evaluable CAC seen on cCTA on clinical decision-making by determining the degree of subsequent invasive testing and to assess the relationship between non-evaluable segments containing CAC and significant stenosis as seen in invasive coronary angiography (ICA). Material and Methods The study comprised of 356 patients who underwent cCTA and subsequent ICA within 2 months between 2005 and 2009. Clinical reports were reviewed to identify the indications for referral to ICA. In a subset of 68 patients where non-diagnostic CAC on cCTA and significant stenosis on ICA were present in the same segment, we correlated and analyzed the underlying stenosis severity of the lesion on ICA to the cCTA. Lesions with CAC were analyzed in a standardized fashion by application of reading rules. Results Non-diagnostic CAC on cCTA prompted ICA in 5.6% of patients. CAC occurred at the site of maximum stenosis in segments with stenosis <50% (95.9% [47/49]), 50-69% (82.4% [28/34]), 70-99% (64.5% [31/48]), and 100% (33.3% [1/3]). At the point of maximum calcium deposit, non-obstructive disease was present in 61.2%. Application of reading rules resulted in a 44% reduction in non-diagnostic cCTA reads. Conclusion Severe CAC may prompt further investigation with ICA. There is less CAC with increasing lesion severity at the point of maximum stenosis. Additional application of reading rules improved non-diagnostic cCTA reads.

Effect of the 2010 task force criteria on reclassification of cardiovascular magnetic resonance criteria for arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: We sought to evaluate the effect of application of the revised 2010 Task Force Criteria (TFC) on the prevalence of major and minor Cardiovascular Magnetic Resonance (CMR) criteria for Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) versus application of the original 1994 TFC. We also assessed the utility of MRI to identify alternative diagnoses for patients referred for ARVC evaluation. METHODS: 968 consecutive patients referred to our institution for CMR with clinical suspicion of ARVC from 1995 to 2010, were evaluated for the presence of major and minor CMR criteria per the 1994 and 2010 ARVC TFC. CMR criteria included right ventricle (RV) dilatation, reduced RV ejection fraction, RV aneurysm, or regional RV wall motion abnormalities. When quantitative measures of RV size and function were not available, and in whom abnormal size or function was reported, a repeat quantitative analysis by 2 qualified CMR physicians in consensus. RESULTS: Of 968 patients, 220 (22.7%) fulfilled either a major or a minor 1994 TFC, and 25 (2.6%) fulfilled any of the 2010 TFC criterion. Among patients meeting any 1994 criteria, only 25 (11.4%) met at least one 2010 criterion. All patients who fulfilled a 2010 criteria also satisfied at least one 1994 criterion. Per the 2010 TFC, 21 (2.2%) patients met major criteria and 4 (0.4%) patients fulfilled at least one minor criterion. Eight patients meeting 1994 minor criteria were reclassified as satisfying 2010 major criteria, while 4 patients fulfilling 1994 major criteria were reclassified to only minor or no criteria under the 2010 TFC.Eighty-nine (9.2%) patients had alternative cardiac diagnoses, including 43 (4.4%) with clinically significant potential ARVC mimics. These included cardiac sarcoidosis, RV volume overload conditions, and other cardiomyopathies. CONCLUSIONS: Application of the 2010 TFC resulted in reduction of total patients meeting any diagnostic CMR criteria for ARVC from 22.7% to 2.6% versus the 1994 TFC. CMR identified alternative cardiac diagnoses in 9.2% of patients, and 4.4% of the diagnoses were potential mimics of ARVC.

Coronary computed tomography angiography at 140 kV versus 120 kV: assessment of image quality and radiation exposure in overweight and moderately obese patients.

BACKGROUND: Although a tube potential of 140 kV is available on most computed tomography (CT) scanners, its incremental diagnostic value versus 120 kV has been controversial. PURPOSE: To retrospectively evaluate the image quality and radiation exposure of cardiac computed tomography angiography (CCTA) performed at 140 kV in comparison to CCTA at 120 kV in overweight and moderately obese patients. MATERIAL AND METHODS: Eighty-eight patients who were referred for CCTA between January 2010 and May 2012 were included. Forty-four patients who were overweight or moderately obese (body mass index [BMI], 25-35 kg/m(2)) underwent CCTA with dual-source CT (DSCT) scanner at 140 kV. Forty-four match controls who underwent CCTA with DSCT at 120 kV were identified per BMI, average heart rate, scan indication, and scan acquisition mode. All scans were performed per routine protocols with direct physician supervision. Quantitative image metrics (CT attenuation, image noise, contrast-to-noise ratio [CNR], and signal-to-noise ratio [SNR] of left main [LM] and proximal right coronary artery [RCA]) were assessed. Effective radiation dose was compared between the two groups. RESULTS: Overall, all scans were diagnostic without any non-evaluable coronary segment per clinical report. 140 kV had a lower attenuation and image noise versus 120 kV (P<0.01). Both SNR and CNR of proximal coronary arteries were similar between 140 kV and 120 kV (SNR, LM P=0.93, RCA P=0.62; CNR, LM P=0.57, RCA P=0.77). 140 kV was associated with a 35.3% increase in effective radiation dose as compared with 120 kV (5.1 [3.6-8.2] vs. 3.3 [2.0-5.1] mSv, respectively; P<0.01). CONCLUSION: 140 kV CCTA resulted in similar image quality but a higher effective radiation dose in comparison to 120 kV CCTA. Therefore, in overweight and moderately obese patients, a tube potential of 120 kV may be sufficient for CCTA with diagnostic image quality.

Anticoagulation Use as an Independent Predictor of Mortality and Major Adverse Cardiovascular Events in Hospitalized COVID-19 Patients: A Multicenter Retrospective Analysis.

Background: Coronavirus disease 2019 (COVID-19) is associated with increased incidence of cardiac arrhythmias and thrombotic events. The adverse cardiovascular outcomes related to ambulatory anticoagulation (AC) therapy in COVID-19 patients are unknown. The goal of this study was to identify the effects of AC use in hospitalized COVID-19 patients. Methods: This is a multicenter, retrospective study that identified 2,801 hospitalized COVID-19 polymerase chain reaction (PCR)-positive patients admitted between March 2020 and July 2021. Of these, 375 (13.4%) were ambulatory AC users. Data were collected from the electronic health records of hospitalized patients. Mortality included in-hospital death and hospice referral. Major adverse cardiovascular events (MACEs) included acute heart failure (HF), myocardial infarction (MI), myocarditis, pulmonary embolism (PE), deep venous thrombosis (DVT), pericardial effusion, pericarditis, stroke, shock, and cardiac tamponade. A Chi-square test was used to analyze categorical variables, and multivariate logistic regression analysis was performed to account for comorbidities. Results: AC non-users exhibited a higher incidence of mortality than AC users (13.9% vs. 7.7%, P = 0.001). However, MACE incidence was higher in AC users than AC non-users (44.8% vs. 26.8%, P < 0.001). The higher MACE incidence was driven by higher rates of acute HF (8.3% vs. 2.5%, P < 0.001), MI (26.9% vs. 18.2%, P < 0.001), PE/DVT (16.3% vs. 2.7%, P < 0.001), pericardial effusion (1.6% vs. 0.5%, P = 0.025), and stroke (2.9% vs. 1.2%, P = 0.018). After multivariate logistic regression, MACE incidence remained higher (odds ratio (OR) = 1.61, 95% confidence interval (CI): 1.27 - 2.05, P < 0.001) and all-cause mortality rate lower (OR = 0.34, 95% CI: 0.23 - 0.52, P < 0.001) in AC users. Conclusions: Ambulatory AC use is associated with increased MACEs but decreased all-cause mortality in patients hospitalized with COVID-19. This study will help physicians identify patients at risk of cardiovascular mortality and direct management based on the identified risk.

Mortality and Major Adverse Cardiovascular Events in Hospitalized Patients With Atrial Fibrillation With COVID-19.

COVID-19 results in increased incidence of cardiac arrhythmias, including atrial fibrillation (AF). However, little is known about the combined effect of AF and COVID-19 on patient outcomes. This study aimed to determine if AF, specifically new-onset AF (NOAF), is associated with increased risk of mortality and major adverse cardiovascular events (MACEs) in hospitalized patients with COVID-19. This multicenter retrospective analysis identified 2,732 patients with COVID-19 admitted between March and December 2020. Data points were manually reviewed in the patients' electronic health records. Multivariate logistic regression was used to assess if AF was associated with death or MACE. Patients with AF (6.4%) had an increased risk of mortality (risk ratio 2.249, 95% confidence interval [CI] 1.766 to 2.864, p <0.001) and MACE (risk ratio 1.753, 95% CI 1.473 to 2.085, p <0.001) compared with those with sinus rhythm. Patients with NOAF had an increased risk of mortality compared with those with existing AF (odds ratio 19.30, 95% CI 5.39 to 69.30, p <0.001); the risk of MACE was comparable between NOAF and patients with existing AF (p = 1). AF during hospitalization with COVID-19 is associated with a higher risk of mortality and MACE. NOAF in patients with COVID-19 is associated with a higher risk of mortality but a similar risk of MACE compared with patients with existing AF.

Coronary Artery Disease as an Independent Predictor of Cardiovascular Mortality in COVID-19 Patients.

Background: Coronavirus disease 2019 (COVID-19) is associated with increased risk of cardiovascular mortality. However, little is known about the combined effect of coronary artery disease (CAD) and COVID-19 on mortality. We aimed to investigate the incidence of cardiovascular and all-cause mortality in COVID-19 patients with CAD. Methods: This multicenter retrospective study identified 3,336 COVID-19 patients admitted between March and December 2020. Data points were manually reviewed in the patients' electronic health records. Multivariate logistic regression was used to assess whether CAD and its subtypes were associated with mortality. Results: This study shows that CAD was not an independent predictor of all-cause mortality (odds ratio (OR): 1.512, 95% confidence interval (CI): 0.1529 - 14.95, P = 0.723). However, there was a significant increase in cardiovascular mortality in patients with CAD compared to those without (OR: 6.89, 95% CI: 2.706 - 17.53, P < 0.001). There was no significant difference in all-cause mortality in patients with left main artery and left anterior descending artery disease (OR: 1.29, 95% CI: 0.80 - 2.08, P = 0.29). However, CAD patients with a history of interventions (e.g., coronary stenting or coronary artery bypass graft) showed increased mortality compared to those solely treated by medical management (OR: 1.93, 95% CI: 1.12 - 3.33, P = 0.017). Conclusions: CAD is associated with a higher incidence of cardiovascular mortality but not all-cause mortality in COVID-19 patients. Overall, this study will help clinicians identify characteristics of COVID-19 patients with increased risk of mortality in the setting of CAD.

Relation of interleukin-6 levels in COVID-19 patients with major adverse cardiac events.

Elevated interleukin-6 (IL-6) levels may correlate with disease severity in COVID-19. We analyzed whether there was an association between elevated IL-6 levels and major adverse cardiac events (MACE) and/or mortality in COVID-19 patients. A retrospective chart review was performed on COVID-19 patients among four hospitals in one health system from March to May 2020, extracting information on baseline characteristics, MACE (i.e., myocardial infarction, stroke, deep venous thrombosis/pulmonary embolism, or shock requiring vasopressor support), mortality, and IL-6 levels. Of the 496 patients hospitalized with COVID-19, 191 patients had an IL-6 level drawn and 68% had elevated IL-6 levels. The elevated IL-6 population had higher odds of developing a MACE compared to the normal IL-6 population (P < 0.0001, odds ratio [OR] = 5.91, 95% confidence interval [CI] = 2.65-14.11). The elevated IL-6 population also had higher mortality rates (28.2% vs 5%, P = 0.0001, OR = 7.47, 95% CI = 2.19-39.32) and an increased incidence of a MACE and/or mortality (58.78% vs 20.00%, P < 0.0001, OR = 5.7, 95% CI 2.65-12.83) compared to the normal IL-6 population. Elevated IL-6 levels in COVID-19 patients may be associated with MACE and/or mortality. Monitoring IL-6 levels in COVID-19 patients may help risk-stratify patients.

Myocardial perfusion imaging analysis in patients with regurgitant valvular heart disease.

BACKGROUND/AIM: We noticed that there was decreased correlation of the findings from myocardial perfusion imaging (MPI) and cardiac catheterization (CATH) in patients with mitral regurgitation (MR) and aortic regurgitation (AR) compared to patients without valve disease. METHODS: Through a systematic review of MPI records at the Harry S. Truman Memorial Veterans' Hospital between 1998 and 2008, we identified 58 patients with at least moderate MR or AR by echocardiogram who underwent cardiac catheterization within 6 months of the MPI study. A control group was formulated with 60 patients who did not have significant MR or AR on echocardiogram and who had both MPI and CATH. Correlation between MPI and CATH was graded as complete, partial, or absent. RESULTS: Correlation between MPI and CATH was lower in the valve disease patients (study group) when compared to controls. Correlation was complete in 76% of study patients and 90% of controls, partial in 15% of study patients and 5% of controls, and absent in 9% of study patients and 5% of controls. Differences between the groups were significant (P < .05). CONCLUSIONS: Patients with regurgitant valvular heart disease may have myocardial perfusion abnormalities that are not associated with angiographic critical coronary stenosis.

Advanced adaptive axial-sequential prospectively electrocardiogram-triggered dual-source coronary computed tomographic angiography in a patient with atrial fibrillation.

Atrial fibrillation is considered a relative contraindication to coronary computed tomographic angiography (CCTA) because image quality and radiation dose-saving measures largely depend on low and stable heart rates. Most published experiences with CCTA during atrial fibrillation have relied on retrospective gating to mitigate artifacts via electrocardiogram editing. However, a large number of patients arrive at the CT suite with irregular heart rates. We present a case in which we used a prospectively electrocardiogram-triggered axial-sequential scan mode with a novel arrhythmia protection algorithm to obtain motion-free, high-quality CCTA images at a low radiation dose.

Pericarditis with pericardial effusion as a delayed complication of COVID-19.

Coronavirus disease 2019 (COVID-19) patients typically present with respiratory symptoms; however, cardiac symptoms, such as pericarditis and pericardial effusion, have also been reported. We report a case of acute pericarditis and pericardial effusion as a delayed complication of COVID-19.

Cardiovascular problems in dialysis patients: impact on survival.

Cardiovascular diseases, in their broad spectrum, are collectively the major cause of death in patients on dialysis. The population of patients treated with peritoneal and hemodialysis are not only subject to the traditional risk factors for heart disease, but also to certain uremia-associated risk factors that are unique in this population. Limited data are available on the effectiveness of routine interventions on cardiovascular outcomes in dialysis patients. Because most dialysis patients are excluded from clinical trials, data from randomized controlled trials regarding outcomes in patients undergoing peritoneal dialysis are almost absent. The present review discusses some of the major cardiovascular problems in the dialysis population, the impact of those problems on survival, and the available therapeutic strategies.

Adherence to the 2010 American College of Cardiology Foundation Appropriate Use Criteria for Cardiac Computed Tomography: Quality Analysis at a Tertiary Referral Center.

BACKGROUND: In November 2010, the American College of Cardiology Foundation published revised appropriateness criteria (AC) for cardiac computed tomography (CT). We evaluated adherence to these criteria by providers of different subspecialties at a tertiary referral center. METHODS: Reports of 383 consecutive patients who underwent clinically indicated cardiac CT from December 1, 2010, to July 31, 2011, were reviewed by physicians with appropriate training in cardiac CT. Scans were classified as appropriate, inappropriate, or uncertain based on the revised 2010 AC. Studies that did not fall under any of the specified indications were labeled as unclassified. Adherence to the AC was also analyzed as a function of provider type. Research scans were excluded from this analysis. RESULTS: Three hundred eight exams (80%) were classified as appropriate; 26 (7%), as inappropriate; 30 (8%), as uncertain; and 19 (5%), as unclassified. Of the 19 (5%) unclassified cardiac CT exams, the most common indication was for evaluation of suspected aortic dissection. Three hundred five exams (80%) were referred by cardiologists; 73 (19%), by internists; and 5 (1%), by neurologists. Of the 305 cardiology-referred studies, 221 (73%) were ordered by general cardiologists; 28 (9%), by interventional cardiologists; and 56 (19%), by electrophysiologists. There was no significant difference in adherence to the criteria between provider specialties or between cardiology subspecialties (P > 0.05). CONCLUSIONS: high across provider specialties.

Defining left ventricular noncompaction using cardiac computed tomography.

PURPOSE: Left ventricular noncompaction (LVNC) is a cardiomyopathy characterized by a distinctive 2-layered appearance of the myocardium because of increased trabeculation and deep intertrabecular recesses. Echocardiography serves as the initial noninvasive diagnostic test. Currently, magnetic resonance imaging (MRI) is increasingly being used to diagnose LVNC because of its improved temporal and spatial resolution. So far, no criteria have been proposed to define pathologic LVNC with the use of computed tomography (CT). MATERIALS AND METHODS: We analyzed CT images using an American Heart Association 17-segment model in 8 patients previously diagnosed with LVNC by clinical diagnosis, echocardiography, and/or MRI, as well as in 11 patients with nonischemic dilated cardiomyopathy, 11 patients with hypertrophic cardiomyopathy, 10 patients with severe aortic stenosis, 9 patients with severe aortic regurgitation, 10 patients with left ventricular hypertrophy due to essential hypertension, and, additionally, in a control group of 20 patients who had normal CT scans without a history of cardiovascular disease. The distribution of LVNC was assessed by qualitative analysis of 17 myocardial segments for the presence or absence of any degree of noncompaction. Each segment was analyzed in each of the 3 end-diastolic long-axis views for the presence or absence of noncompaction, and the most prominent trabeculation was chosen for measurement. The left ventricular apex was excluded. Thickness of noncompacted and compacted myocardium was measured perpendicular to the compacted myocardium. The ratio of noncompacted to compacted (NC:C) myocardium was calculated for each segment. Receiver operating characteristics were used to generate cutoff values with sensitivity and specificity to distinguish the LVNC group from other groups. RESULTS: An end-diastolic NC:C ratio >2.3 distinguished pathologic LVNC with 88% sensitivity and 97% specificity; positive and negative predictive values were 78% and 99%, respectively. CONCLUSIONS: CT using the standard MRI NC:C ratio cutoff >2.3 accurately characterizes pathologic LVNC.

Resolution of an intracardiac mass with chemotherapy.

Right atrial intracardiac tumours are uncommonly seen during echocardiography. Our patient presented with primary mediastinal large B-cell lymphoma with intracardiac involvement. The tumour was seen by echocardiography and the extent of the tumour was defined by CT scan of the chest. Following chemotherapy directed to her specific tumour cell type, there was complete resolution of the intracardiac mass.

Outcome of patients with regadenoson-induced ST-segment depression but normal perfusion on single-photon emission computed tomography.

The prognostic significance of ischemic electrocardiographic (ECG) changes during Regadenoson vasodilator stress in patients with normal single-photon emission computed tomographic myocardial perfusion imaging (SPECT-MPI) is not well described. Of 2473 patients who underwent Regadenoson vasodilator stress testing, 43 (77% women, mean age 72 ± 10 years) patients were included in the study. During a mean follow-up of 14 ± 7 months, cardiac death occurred in 1 patient; 5 patients underwent coronary revascularization and none had myocardial infarction. The annual rate of cardiac death and coronary revascularization was 1.9% and 9.9%, respectively. The finding of ischemic ECG changes with normal SPECT-MPI during regadenoson vasodilator stress testing is uncommon, occurs primarily in older women, and is associated with moderately higher subsequent cardiac event rate.

Assessment of image quality and radiation dose of prospectively ECG-triggered adaptive dual-source coronary computed tomography angiography (cCTA) with arrhythmia rejection algorithm in systole versus diastole: a retrospective cohort study.

In this study, we sought to evaluate the image quality and effective radiation dose of prospectively ECG-triggered adaptive systolic (PTA-systolic) dual-source CTA versus prospectively triggered adaptive diastolic (PTA-diastolic) dual-source CTA in patients of unselected heart rate and rhythm. This retrospective cohort study consisted of 41 PTA-systolic and 41 matched PTA-diastolic CTA patients whom underwent clinically indicated 128-slice dual source CTA between December 2010 to June 2012. Image quality and motion artifact score (both on a Likert scale 1-4 with 4 being the best), effective dose, and CTDIvol were compared. The effect of heart rate (HR) and heart rate variability [HRV] on image motion artifact score and CTDIvol was analyzed with Pearson's correlation coefficient. All 82 exams were considered diagnostic with 0 non-diagnostic segments. PTA-systolic CTA patients had a higher maximum HR, wider HRV, were less likely to be in sinus rhythm, and received less beta-blocker vs. PTA-diastolic CTA patients. No difference in effective dose was observed (PTA-systolic vs. PTA-diastolic CTA: 2.9 vs. 2.2 mSv, p = 0.26). Image quality score (3.3 vs. 3.5, p < 0.05) and motion artifact score (3.5 vs. 3.8, p < 0.05) were lower in PTA-systolic CTAs than in PTA-diastolic CTAs. For PTA-systolic CTAs, an increase in HR was not associated with a negative impact on motion artifact score nor CTDIvol. For PTA-diastolic CTA, an increase in HR was associated with increased motion artifacts and CTDIvol. HRV demonstrated no correlation with motion artifact and CTDIvol for both PTA-systolic and PTA-diastolic CTAs. In conclusion, both PTA-diastolic CTA and PTA-systolic CTA yielded diagnostic examinations at unselected heart rates and rhythms with similar effective radiation, but PTA-systolic CTA resulted in more consistent radiation exposure and image quality across a wide range of rates and rhythms.

Weekly dose reports: the effects of a continuous quality improvement initiative on coronary computed tomography angiography radiation doses at a tertiary medical center.

RATIONALE AND OBJECTIVES: Numerous protocols have been developed to reduce cardiac computed tomography angiography (cCTA) radiation dose while maintaining image quality. However, cCTA practice is highly dependent on physician and technologist experience and education. In this study, we sought to evaluate the incremental value of real-time feedback via weekly dose reports on a busy cCTA service. MATERIALS AND METHODS: This time series analysis consisted of 450 consecutive patients whom underwent physician-supervised cCTA for clinically indicated native coronary evaluation between April 2011 and January 2013, with 150 patients before the initiation of weekly dose report (preintervention period: April-September 2011) and 150 patients after the initiation (postintervention period: September 2011-February 2012). To assess whether overall dose reductions were maintained over time, results were compared to a late control group consisting of 150 consecutive cCTA exams, which were performed after the study (September 2012-January 2013). Patient characteristics and effective radiation were recorded and compared. RESULTS: Total radiation dose was significantly lower in the postintervention period (3.4 mSv [1.7-5.7] and in the late control group (3.3 mSv [2.0-5.3] versus the preintervention period (4.1 mSv [2.1-6.6] (P = .005). The proportion of high-dose outliers was also decreased in the postintervention period and late control period (exams <10 mSv were 88.0% preintervention vs. 97.3% postintervention vs. 95.3% late control; exams <15 mSv were 98.0% preintervention vs. 100.0% postintervention vs. 98.7% late control; exams <20.0 mSv were 98.7% preintervention vs. 100.0% postintervention vs. 100.0% late control). CONCLUSION: Weekly dose report feedback of site radiation doses to patients undergoing physician-supervised cCTA resulted in significant overall dose reduction and reduction of high-dose outliers. Overall dose reductions were maintained beyond the initial study period.

Cardiac computed tomography angiography with automatic tube potential selection: effects on radiation dose and image quality.

PURPOSE: Automatic exposure control (AEC) algorithms are widely available in coronary computed tomography angiography (CTA) and have been shown to reduce radiation doses by adjusting tube current to patient size. However, the effects of anthropometry-based automatic potential selection (APS) on image quality and radiation dose are unknown. We sought to investigate the effect of an APS algorithm on coronary CTA radiation dose and image quality. MATERIALS AND METHODS: For this retrospective case-control study we selected 38 patients who had undergone coronary CTA for coronary artery assessment in whom tube potential and tube current were selected automatically by a combined automatic tube potential and tube current selection algorithm (APS-AEC) and compared them with 38 controls for whom tube voltage was selected according to standard body mass index (BMI) cutoffs and tube current was selected using automatic exposure control (BMI-AEC). Controls were matched for BMI, heart rate, heart rhythm, sex, acquisition mode, and indication for cardiac CTA. Image quality was assessed as contrast-to-noise ratio and signal-to-noise ratio in the proximal coronary arteries. Subjective reader assessment was also made. Total radiation dose (volume-weighted computed tomography dose index) was measured and compared between the 2 groups. In the study group, comparison was made with conventional BMI-guided prior protocols (site protocols and Society of Cardiovascular Computed Tomography recommendations) through disagreement analysis. RESULTS: The APS-AEC cases received 29.8% lower overall radiation dose compared with controls (P=not significant). APS-AEC resulted in a significantly higher signal-to-noise ratio of the proximal coronary arteries (P<0.01) and contrast-to-noise ratio of the left main (P=0.01). In the study cases, the APS resulted in a change in tube potential versus site protocols and Society of Cardiovascular Computed Tomography recommendations in 45% (n=17) and 50% (n=19) of patients, respectively. CONCLUSION: Automated tube potential selection software resulted in significantly improved objective image quality versus standard BMI-based methods of tube potential selection, without increased radiation doses.

Clinical experiences of delayed contrast enhancement with cardiac computed tomography: case series.

BACKGROUND: Myocardial delayed enhancement (MDE) by gadolinium-enhanced cardiac MRI is well established for myocardial scar assessment in ischemic and non-ischemic heart disease. The role of MDE by cardiac CT (CT-MDE) is not yet defined. FINDINGS: We reviewed all clinical cases of CT-MDE at a tertiary referral center to present the cases as a case series. All clinical cardiac CT exams which utilized CT-MDE imaging between January 1, 2005 and October 1, 2010 were collected as a series and their findings were also compared with available myocardial imaging to assess for myocardial abnormalities, including echocardiography (wall motion, morphology), cardiac MRI (delayed enhancement, morphology), SPECT MPI (perfusion defects). 5,860 clinical cardiac CT exams were performed during the study period. CT-MDE was obtained in 18 patients and was reported to be present in 9 patients. The indications for CT-MDE included ischemic and non-ischemic heart diseases. In segments positive for CT-MDE, there was excellent agreement of CT with other modalities: echocardiography (n=8) demonstrated abnormal morphology and wall motion (k=1.0 and k=0.82 respectively); prior MRI (n=2) demonstrated abnormal delayed enhancement (MR-MDE) (k=1.0); SPECT MPI (n=1) demonstrated fixed perfusion defects (k=1.0). In the subset of patients without CT-MDE, no abnormal segments were identified by echocardiography (n=8), MRI (n=1) and nuclear MPI (n=0). CONCLUSIONS: CT-MDE was performed in rare clinical situations. The indications included both ischemic and non-ischemic heart disease and there was an excellent agreement between CT-MDE and abnormal myocardium by echocardiography, cardiac MRI, and nuclear MPI.

Feasibility of aortic valve assessment with low dose prospectively triggered adaptive systolic (PTAS) cardiac computed tomography angiography.

BACKGROUND: Cardiac computed tomography angiography (CTA) is feasible for aortic valve evaluation, but retrospective gated protocols required high radiation doses for aortic valve assessment. A prospectively triggered adaptive systolic (PTAS) cardiac CT protocol was recently described in arrhythmia using second-generation dual-source CT. In this study, we sought to evaluate the feasibility of PTAS CTA to assess the aortic valve at a low radiation dose. FINDINGS: A retrospective cohort of 29 consecutive patients whom underwent PTAS protocols for clinical indications other than aortic valve assessment and whom also received echocardiography within 2 months of CT, was identified. Images were reviewed for aortic valve morphology (tricuspid/bicuspid/prosthetic) and stenosis (AS) by experienced blinded readers. Accuracy versus echocardiography and radiation doses were assessed. CONCLUSIONS: PTAS CTA protocols using second-generation dual-source CT for aortic valve evaluation are feasible at low doses. This protocol should be investigated further in larger cohorts.