Exertional Angina in a Young Woman Caused by Large Cardiac Paraganglioma.

Coronary ischemia is uncommon in patients in their third decade of life. We present a 21-year-old woman with classic exertional angina secondary to a large cardiac paraganglioma. Cardiac paragangliomas are rare extra-adrenal neuroendocrine tumors that arise from chromaffin cells. Cardiac symptoms can be related to catecholamine excess or anatomical compression.

Feasibility and Potential Effectiveness of a Smartphone Zero-Time Exercise Intervention for Promoting Physical Activity and Fitness in Patients With Coronary Heart Disease: A Pilot Randomized Controlled Trial.

Background: Zero-time Exercise (ZTEx), a simple strength- and stamina-enhancing physical activity (PA) requiring no extra equipment, can potentially increase PA and fitness. This pilot trial examined the feasibility and potential effectiveness of a smartphone ZTEx intervention to promote PA and fitness in patients with coronary heart disease (CHD). Methods: A parallel-group assessor-blinded pilot randomized controlled trial was conducted on Chinese patients with stable coronary heart disease (CHD) in three cardiology clinics. The experimental group received a 15-min brief individual face-to-face session and a 12-week ZTEx instant messaging with 28 picture e-messages and a smartphone ZTEx application (ZTExApp). The control group received the same duration of individual session and number and format of e-messages, but the content was healthy eating and breathing exercise. The feasibility was assessed based on: attrition rate, usage, response rate and perception of the intervention. The outcome evaluation included primary outcome (PA), fitness, exercise self-efficacy and intention, perceived happiness and health, and quality of life. A linear mixed model was used with intention-to-treat analysis adjusting for sex, age and baseline values. A semi-structured interview was conducted to collect feedback from the experiment group. Results: One hundred thirty-nine patients (mean age 59.8 ± 6.6; 71.2% male) were randomized to the experimental group (n = 70) or control group (n = 69), and 80% (56/70) and 82% (57/69) of patients completed the 12-week follow-up assessment, respectively. The attrition rate was 18.7%. The experimental group reported that ZTEx was feasible to integrate PA into their daily life and appreciated the picture e-messages, and 95% of them sent feedback to us, but only 19.6% (13/70) of the participants entered their PA information into the e-diary of the ZTExApp. The experimental group had a significantly greater increase in time spent walking [mean difference (95% CI): 155.3 (10.1, 300.4), P = 0.04, Cohen's d = 0.34] than the control group. Conclusions: This pilot study showed using a brief ZTEx face-to-face session with picture e-messages empowered patients with CHD to integrate PA into daily life. Future definitive trials with a longer follow-up and a more user-friendly ZTExApp interface are necessary to determine the effectiveness of the smartphone ZTEx intervention in enhancing PA and related outcomes. Trial Registration: The research protocol was registered at the Hong Kong University Clinical Trials Registry (HKUCTR) on 22 Jul 2016 (Study identifier: HKUCTR-2165) and was also retrospectively registered at the National Institutes of Health (identifier number: NCT03464331) on 14 March 2018.

A clinical model to identify patients with high-risk coronary artery disease.

OBJECTIVES: This study sought to develop a clinical model that identifies patients with and without high-risk coronary artery disease (CAD). BACKGROUND: Although current clinical models help to estimate a patient's pre-test probability of obstructive CAD, they do not accurately identify those patients with and without high-risk coronary anatomy. METHODS: Retrospective analysis of a prospectively collected multinational coronary computed tomographic angiography (CTA) cohort was conducted. High-risk anatomy was defined as left main diameter stenosis ≥50%, 3-vessel disease with diameter stenosis ≥70%, or 2-vessel disease involving the proximal left anterior descending artery. Using a cohort of 27,125, patients with a history of CAD, cardiac transplantation, and congenital heart disease were excluded. The model was derived from 24,251 consecutive patients in the derivation cohort and an additional 7,333 nonoverlapping patients in the validation cohort. RESULTS: The risk score consisted of 9 variables: age, sex, diabetes, hypertension, current smoking, hyperlipidemia, family history of CAD, history of peripheral vascular disease, and chest pain symptoms. Patients were divided into 3 risk categories: low (≤7 points), intermediate (8 to 17 points) and high (≥18 points). The model was statistically robust with area under the curve of 0.76 (95% confidence interval [CI]: 0.75 to 0.78) in the derivation cohort and 0.71 (95% CI: 0.69 to 0.74) in the validation cohort. Patients who scored ≤7 points had a low negative likelihood ratio (<0.1), whereas patients who scored ≥18 points had a high specificity of 99.3% and a positive likelihood ratio (8.48). In the validation group, the prevalence of high-risk CAD was 1% in patients with ≤7 points and 16.7% in those with ≥18 points. CONCLUSIONS: We propose a scoring system, based on clinical variables, that can be used to identify patients at high and low pre-test probability of having high-risk CAD. Identification of these populations may detect those who may benefit from a trial of medical therapy and those who may benefit most from an invasive strategy.

Current but not past smoking increases the risk of cardiac events: insights from coronary computed tomographic angiography.

AIMS: We evaluated coronary artery disease (CAD) extent, severity, and major adverse cardiac events (MACEs) in never, past, and current smokers undergoing coronary CT angiography (CCTA). METHODS AND RESULTS: We evaluated 9456 patients (57.1 ± 12.3 years, 55.5% male) without known CAD (1588 current smokers; 2183 past smokers who quit ≥3 months before CCTA; and 5685 never smokers). By risk-adjusted Cox proportional-hazards models, we related smoking status to MACE (all-cause death or non-fatal myocardial infarction). We further performed 1:1:1 propensity matching for 1000 in each group evaluate event risk among individuals with similar age, gender, CAD risk factors, and symptom presentation. During a mean follow-up of 2.8 ± 1.9 years, 297 MACE occurred. Compared with never smokers, current and past smokers had greater atherosclerotic burden including extent of plaque defined as segments with any plaque (2.1 ± 2.8 vs. 2.6 ± 3.2 vs. 3.1 ± 3.3, P < 0.0001) and prevalence of obstructive CAD [1-vessel disease (VD): 10.6% vs. 14.9% vs. 15.2%, P < 0.001; 2-VD: 4.4% vs. 6.1% vs. 6.2%, P = 0.001; 3-VD: 3.1% vs. 5.2% vs. 4.3%, P < 0.001]. Compared with never smokers, current smokers experienced higher MACE risk [hazard ratio (HR) 1.9, 95% confidence interval (CI) 1.4-2.6, P < 0.001], while past smokers did not (HR 1.2, 95% CI 0.8-1.6, P = 0.35). Among matched individuals, current smokers had higher MACE risk (HR 2.6, 95% CI 1.6-4.2, P < 0.001), while past smokers did not (HR 1.3, 95% CI 0.7-2.4, P = 0.39). Similar findings were observed for risk of all-cause death. CONCLUSION: Among patients without known CAD undergoing CCTA, current and past smokers had increased burden of atherosclerosis compared with never smokers; however, risk of MACE was heightened only in current smokers.

Gender differences in the prevalence, severity, and composition of coronary artery disease in the young: a study of 1635 individuals undergoing coronary CT angiography from the prospective, multinational confirm registry.

OBJECTIVE: Prior studies examining coronary atherosclerosis in the young have been limited by retrospective analyses in small cohorts. We examined the relationship between cardiovascular risk factors (RFs) and prevalence and severity of coronary atherosclerosis in a large, prospective, multinational registry of consecutive young individuals undergoing coronary computerized tomographic angiography (CCTA). METHOD AND RESULTS: Of 27 125 patients undergoing CCTA, 1635 young (<45 years) individuals without known coronary artery disease (CAD) or coronary anomalies were identified. Coronary plaque was assessed for any CAD, obstructive CAD (≥50% stenosis), and presence of calcified plaque (CP) and non-calcified plaque (NCP). Among 1635 subjects (70% men, age 38 ± 6 years), any CAD, obstructive CAD, CP, and NCP were observed in 19, 4, 5, and 8%, respectively. Compared with women, men demonstrated higher rates of any CAD (21 vs. 12%, P < 0.001), CP (6 vs. 3%, P = 0.01), and NCP (9 vs. 5%, P = 0.008), although no difference was observed for rates of obstructive CAD (5 vs. 4%, P = 0.46). Any CAD, obstructive CAD, and NCP were higher for young individuals with diabetes, hypertension, dyslipidaemia, current smoking, or family history of CAD; while only diabetes and dyslipidaemia were associated with CP. Increasing cardiovascular RFs was associated with a greater prevalence and extent and severity of CAD, with individuals with 0, 1, 2, ≥3 RFs manifesting a dose-response increase in any CAD (P < 0.001, for trend), obstructive CAD (P < 0.001, for trend), NCP (P < 0.001, for trend), and CP (P < 0.001, for trend). In multivariable analysis adjusting for sex and cardiovascular RFs, male sex was the strongest predictor for any CAD (odds ratio [OR] = 1.95, 95% confidence interval [CI] = 1.43-2.66, P < 0.001), CP (OR = 1.46, 95% CI = 1.08-1.98, P = 0.01), and NCP (OR = 1.33, 95% CI = 1.06-1.67, P = 0.01); family history of CAD was the strongest predictor for obstructive CAD (OR = 2.71, 95% CI = 1.65-4.45, P < 0.001). CONCLUSION: Any and obstructive CAD is present in 1 in 5 and 1 in 20 young individuals, respectively, with family history associated with the greatest risk of obstructive CAD.

Optimizing image contrast display improves quantitative stenosis measurement in heavily calcified coronary arterial segments on coronary CT angiography: A proof-of-concept and comparison to quantitative invasive coronary angiography.

RATIONALE AND OBJECTIVES: Blooming artifact from calcified plaques often renders measurement of stenosis impossible on coronary computed tomographic angiography (CTA). We sought to evaluate the impact of modifying window level on reducing blooming artifact, and its impact on stenosis quantification. MATERIALS AND METHODS: We analyzed 125 calcified segments from 53 patients who underwent CTA and invasive coronary angiography (ICA). Segmental stenosis on CTA was measured using three window settings: width of 1000 Hounsfield units (HU) and level of 200 HU ("default"), 1500/200 HU ("widened"), and width and level based on the mean HU of the calcified plaque and pericoronary fat ("calcium-specific"). Segmental stenosis on ICA was quantified by a blinded experienced reader. RESULTS: ICA found ≥50% stenosis in 30 segments. Displaying segments with widened and calcium-specific settings improved overall accuracy of detecting ≥50% stenosis (P's < 0.001) by increasing the rate of accurately quantifying <50% stenosis (P's < 0.001), and improved correlation of stenosis quantification to ICA (P's < 0.05). There was no difference in stenosis quantification accuracy between widened and calcium-specific window settings. Limits of agreement between CTA stenosis quantification and ICA narrowed with widened and calcium-specific settings. CONCLUSIONS: We showed for the first time that in calcified segments, widening display window width significantly improved CTA quantification of stenosis compared to ICA.

Atrioesophageal fistula during cryoballoon ablation for atrial fibrillation.

To date, there is 1 case report publication of AE fistula during the employment of the first-generation cryoballoon (Gen-1). Recently the Arctic Front Advance system (second-generation cryoballoon) was introduced into the US and EU markets. For the purpose of peer education, we report a case of AE fistula that occurred during the utilization of the second-generation cryoballoon (Gen-2). Additionally, we review current best practices that may reduce the risk of AE fistula during any AF ablation procedure.

Relationship of dyspnea vs. typical angina to coronary artery disease severity, burden, composition and location on coronary CT angiography.

OBJECTIVE: Symptom presentations suspicious for coronary artery disease (CAD) vary widely. While dyspnea is associated with worse prognosis than typical angina (TypAng) for patients referred for non-invasive CAD imaging, the relation of dyspnea vs. TypAng to adverse measures of CAD prognosis-including severity, burden, composition, and myocardium at risk-has not been examined. METHODS: We studied 1443 consecutive individuals without known CAD (mean 61 ± 13 years, 61.6% men) undergoing coronary computed tomographic angiography (CCTA) who presented with dyspnea (n = 170), TypAng (n = 249) or no dyspnea or TypAng (n = 1024). Multivariable logistic regression was performed to evaluate the association of dyspnea or TypAng to obstructive CAD (≥70% stenosis), plaque burden (total segments with plaque), composition (noncalcified, partially calcified) and location (proximal, mid, or distal location in a coronary artery). RESULTS: By multivariable logistic regression, both dyspnea (OR1.9, 95% CI 1.1-3.3, p = 0.02) and TypAng (OR1.9, 95% CI 1.2-3.1, p = 0.01) were associated with obstructive CAD as compared to individuals without dyspnea or TypAng, while dyspnea (OR1.8, 95% CI 1.1-3.1, p = 0.02), but not TypAng (OR1.1, 95% CI 0.7-1.6, p = 0.76) was associated with plaque in the proximal portions of coronary arteries. Neither symptom type was associated with differences in plaque burden nor composition. CONCLUSION: Both dyspnea and TypAng are associated with higher rates of obstructive CAD compared to those without dyspnea or TypAng, but only dyspnea is associated with coronary plaque in proximal vessel portions.

Optimized prognostic score for coronary computed tomographic angiography: results from the CONFIRM registry (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry).

OBJECTIVES: The aim of this study was to analyze the predictive value of coronary computed tomography angiography (CCTA) and to model and validate an optimized score for prognosis of 2-year survival on the basis of a patient population with suspected coronary artery disease (CAD). BACKGROUND: Coronary computed tomography angiography carries important prognostic information in addition to the detection of obstructive CAD. But it is still unclear how the results of CCTA should be interpreted in the context of clinical risk predictors. METHODS: The analysis is based on a test sample of 17,793 patients and a validation sample of 2,506 patients, all with suspected CAD, from the international CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry. On the basis of CCTA data and clinical risk scores, an optimized score was modeled. The endpoint was all-cause mortality. RESULTS: During a median follow-up of 2.3 years, 347 patients died. The best CCTA parameter for prediction of mortality was the number of proximal segments with mixed or calcified plaques (C-index 0.64, p < 0.0001) and the number of proximal segments with a stenosis >50% (C-index 0.56, p = 0.002). In an optimized score including both parameters, CCTA significantly improved overall risk prediction beyond National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) score as best clinical score. According to this score, a proximal segment with either a mixed or calcified plaque or a stenosis >50% is equivalent to a 5-year increase in age or the risk of smoking. CONCLUSIONS: In CCTA, both plaque burden and stenosis, particularly in proximal segments, carry incremental prognostic value. A prognostic score on the basis of this data can improve risk prediction beyond clinical risk scores.

A conserved lysine residue controls iron-sulfur cluster redox chemistry in Escherichia coli fumarate reductase.

The Escherichia coli respiratory complex II paralogs succinate dehydrogenase (SdhCDAB) and fumarate reductase (FrdABCD) catalyze interconversion of succinate and fumarate coupled to quinone reduction or oxidation, respectively. Based on structural comparison of the two enzymes, equivalent residues at the interface between the highly homologous soluble domains and the divergent membrane anchor domains were targeted for study. This included the residue pair SdhB-R205 and FrdB-S203, as well as the conserved SdhB-K230 and FrdB-K228 pair. The close proximity of these residues to the [3Fe-4S] cluster and the quinone binding pocket provided an excellent opportunity to investigate factors controlling the reduction potential of the [3Fe-4S] cluster, the directionality of electron transfer and catalysis, and the architecture and chemistry of the quinone binding sites. Our results indicate that both SdhB-R205 and SdhB-K230 play important roles in fine tuning the reduction potential of both the [3Fe-4S] cluster and the heme. In FrdABCD, mutation of FrdB-S203 did not alter the reduction potential of the [3Fe-4S] cluster, but removal of the basic residue at FrdB-K228 caused a significant downward shift (>100mV) in potential. The latter residue is also indispensable for quinone binding and enzyme activity. The differences observed for the FrdB-K228 and Sdh-K230 variants can be attributed to the different locations of the quinone binding site in the two paralogs. Although this residue is absolutely conserved, they have diverged to achieve different functions in Frd and Sdh.

Assessment of the morphological features of degenerative mitral valve disease using 64-slice multi detector computed tomography.

BACKGROUND: Patients with severe mitral regurgitation may be screened for coronary artery disease with the use of cardiac computed tomography before valve surgery. OBJECTIVE: We hypothesized that dual-source multidetector computed tomography (DSCT) could effectively predict the culprit mitral valve scallop identified during surgery among patients with degenerative mitral valve disease undergoing surgical mitral valve repair. METHODS: Twenty-six patients (7 women) with known severe mitral regurgitation underwent elective mitral valve repair from September 2006 through December 2009 at our institution. An additional 10 patients underwent aortic valve replacement and had no documented history of mitral valve disease. All patients underwent transthoracic echocardiography and had retrospectively gated DSCT performed to evaluate the coronary arteries before surgery. Each mitral scallop was identified as either normal, prolapsed, or flail. CT findings were compared with operative findings, which were guided by intraoperative transesophageal echocardiography (TEE). RESULTS: In the 26 patients examined, DSCT identified flail in 23 scallops and prolapse in 48. DSCT agreed with operative findings on identification of the culprit scallop in 25 of 26 patients. On a per-patient and per-scallop basis, the observed κ statistic for agreement between DSCT and operative findings was 0.82. Of the 60 scallops in the aortic valve group, all were judged to be normal by both DSCT and TEE. CONCLUSIONS: In patients with degenerative mitral valve disease undergoing cardiac surgery, DSCT demonstrates excellent agreement with intraoperative findings. DSCT can be used to identify the affected mitral valve scallop and its structure in patients who are candidates for mitral valve repair.

All-cause mortality benefit of coronary revascularization vs. medical therapy in patients without known coronary artery disease undergoing coronary computed tomographic angiography: results from CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry).

AIMS: To date, the therapeutic benefit of revascularization vs. medical therapy for stable individuals undergoing invasive coronary angiography (ICA) based upon coronary computed tomographic angiography (CCTA) findings has not been examined. METHODS AND RESULTS: We examined 15 223 patients without known coronary artery disease (CAD) undergoing CCTA from eight sites and six countries who were followed for median 2.1 years (interquartile range 1.4-3.3 years) for an endpoint of all-cause mortality. Obstructive CAD by CCTA was defined as a ≥50% luminal diameter stenosis in a major coronary artery. Patients were categorized as having high-risk CAD vs. non-high-risk CAD, with the former including patients with at least obstructive two-vessel CAD with proximal left anterior descending artery involvement, three-vessel CAD, and left main CAD. Death occurred in 185 (1.2%) patients. Patients were categorized into two treatment groups: revascularization (n = 1103; 2.2% mortality) and medical therapy (n = 14 120, 1.1% mortality). To account for non-randomized referral to revascularization, we created a propensity score developed by logistic regression to identify variables that influenced the decision to refer to revascularization. Within this model (C index 0.92, χ2 = 1248, P < 0.0001), obstructive CAD was the most influential factor for referral, followed by an interaction of obstructive CAD with pre-test likelihood of CAD (P = 0.0344). Within CCTA CAD groups, rates of revascularization increased from 3.8% for non-high-risk CAD to 51.2% high-risk CAD. In multivariable models, when compared with medical therapy, revascularization was associated with a survival advantage for patients with high-risk CAD [hazards ratio (HR) 0.38, 95% confidence interval 0.18-0.83], with no difference in survival for patients with non-high-risk CAD (HR 3.24, 95% CI 0.76-13.89) (P-value for interaction = 0.03). CONCLUSION: In an intermediate-term follow-up, coronary revascularization is associated with a survival benefit in patients with high-risk CAD by CCTA, with no apparent benefit of revascularization in patients with lesser forms of CAD.

Statins use and coronary artery plaque composition: results from the International Multicenter CONFIRM Registry.

OBJECTIVE: The effect of statins on coronary artery plaque features beyond stenosis severity is not known. Coronary CT angiography (CCTA) is a novel non-invasive method that permits direct visualization of coronary atherosclerotic features, including plaque composition. We evaluated the association of statin use to coronary plaque composition type in patients without known coronary artery disease (CAD) undergoing CCTA. METHODS: From consecutive individuals, we identified 6673 individuals (2413 on statin therapy and 4260 not on statin therapy) with no known CAD and available statin use status. We studied the relationship between statin use and the presence and extent of specific plaque composition types, which was graded as non-calcified (NCP), mixed (MP), or calcified (CP) plaque. RESULTS: The mean age was 59 ± 11 (55% male). Compared to the individuals not taking statins, those taking statins had higher prevalence of risk factors and obstructive CAD. In multivariable analyses, statin use was associated with increased the presence of MP [odds ratio (OR) 1.46, 95% confidence interval (CI) 1.27-1.68), p < 0.001] and CP (OR 1.54, 95% CI 1.36-1.74, p < 0.001), but not NCP (OR 1.11, 95% CI 0.96-1.29, p = 0.1). Further, in multivariable analyses, statin use was associated with increasing numbers of coronary segments possessing MP (OR 1.52, 95% CI 1.34-1.73, p < 0.001) and CP (OR 1.52, 95% CI 1.36-1.70, p < 0.001), but not coronary segments with NCP (OR 1.09, 95% CI 0.94-1.25, p = 0.2). CONCLUSION: Statin use is associated with an increased prevalence and extent of coronary plaques possessing calcium. The longitudinal effect of statins on coronary plaque composition warrants further investigation.

Low radiation coronary calcium scoring by dual-source CT with tube current optimization based on patient body size.

BACKGROUND: Reducing tube voltage from 120 kV to 100 kV during noncontrast CT for the detection of coronary artery calcium reduces patient radiation exposure. OBJECTIVE: We investigated whether coronary calcium scoring by multidetector row CT can be performed at reduced tube current, resulting in lower radiation dose to the patient. METHODS: Sixty-six outpatients were scanned on the same visit by dual-source CT (DSCT) with a standard protocol (120 kVp, 150 mAs), followed by a scan with reduced tube current: 85 mAs for patients with body mass index (BMI) ≤ 30 kg/m(2) and weight ≤ 85 kg, and 120 mAs for patients with BMI > 30 kg/m(2) or weight > 85 kg. Low-dose scans were scored by an experienced reader blinded to the standard scan. RESULTS: Agatston scores (ASs) and calcium volume for standard versus low-dose scans were 236 ± 581 versus 234 ± 586 (P = 0.65, NS), and 189 ± 460 mm(3) versus 184 ± 455 mm(3) with excellent correlation (r = 1.0, P < 0.0001), and no significant difference (P = 0.14, NS). Effective radiation dose for the low-dose protocol (1.0 ± 0.2 mSv) was significantly lower than for the standard protocol (1.7 ± 0.2 mSv; P < 0.0001). Image noise was higher for the low-dose scan (18.8 ± 5.5 HU vs 15.2 ± 4.8 HU; P < 0.0001), but both were within target limits. CONCLUSION: Noncontrast CT for measurement of coronary artery calcium with lower tube current optimized for patient body size is equivalent to standard methods at 40% lower radiation dose, indicating that radiation dose can be lowered for coronary calcium scanning.

Prevalence and severity of coronary artery disease and adverse events among symptomatic patients with coronary artery calcification scores of zero undergoing coronary computed tomography angiography: results from the CONFIRM (Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter) registry.

OBJECTIVES: The purpose of this study was to describe the prevalence and severity of coronary artery disease (CAD) in relation to prognosis in symptomatic patients without coronary artery calcification (CAC) undergoing coronary computed tomography angiography (CCTA). BACKGROUND: The frequency and clinical relevance of CAD in patients without CAC are unclear. METHODS: We identified 10,037 symptomatic patients without CAD who underwent concomitant CCTA and CAC scoring. CAD was assessed as <50%, ≥50%, and ≥70% stenosis. All-cause mortality and the composite endpoint of mortality, myocardial infarction, or late coronary revascularization (≥90 days after CCTA) were assessed. RESULTS: Mean age was 57 years, 56% were men, and 51% had a CAC score of 0. Among patients with a CAC score of 0, 84% had no CAD, 13% had nonobstructive stenosis, and 3.5% had ≥50% stenosis (1.4% had ≥70% stenosis) on CCTA. A CAC score >0 had a sensitivity, specificity, and negative and positive predictive values for stenosis ≥50% of 89%, 59%, 96%, and 29%, respectively. During a median of 2.1 years, there was no difference in mortality among patients with a CAC score of 0 irrespective of obstructive CAD. Among 8,907 patients with follow-up for the composite endpoint, 3.9% with a CAC score of 0 and ≥50% stenosis experienced an event (hazard ratio: 5.7; 95% confidence interval: 2.5 to 13.1; p < 0.001) compared with 0.8% of patients with a CAC score of 0 and no obstructive CAD. Receiver-operator characteristic curve analysis demonstrated that the CAC score did not add incremental prognostic information compared with CAD extent on CCTA for the composite endpoint (CCTA area under the curve = 0.825; CAC + CCTA area under the curve = 0.826; p = 0.84). CONCLUSIONS: In symptomatic patients with a CAC score of 0, obstructive CAD is possible and is associated with increased cardiovascular events. CAC scoring did not add incremental prognostic information to CCTA.

Prognostic assessment of coronary artery bypass patients with 64-slice computed tomography angiography: anatomical information is incremental to clinical risk prediction.

OBJECTIVES: We sought to determine the incremental prognostic value of 64 multi-slice coronary computed tomography angiography (CCTA) in coronary artery bypass graft (CABG) patients. BACKGROUND: Prognostication in CABG patients can be difficult. Anatomical assessment of native coronary artery disease and graft patency might provide useful information, but the utility of CCTA in the assessment of CABG patients is unknown. METHODS: Six hundred fifty-seven CABG patients with all-cause mortality follow-up were identified from a multicenter CCTA registry, of 10,628 patients from 5 CCTA centers. Clinical risk was profiled with modified logistic and additive EuroSCOREs (European Systems for Cardiac Operative Risk Evaluations). The CCTA defined coronary anatomy. Patients were classified by unprotected coronary territory (UCT) or a summary of native vessel disease and graft patency: the coronary artery protection score (CAPS). RESULTS: Forty-four deaths occurred during a mean follow-up of 20 months. Left ventricular ejection fraction, creatinine, age, severity of native vessel disease, UCT, CAPS, and EuroSCOREs were univariate predictors of mortality (p < 0.001). In multivariate analysis with additive EuroSCORE, UCT (p = 0.004) and CAPS were predictive of events (p < 0.001). In comparison with additive EuroSCORE, CAPS score was associated with a 27% net reclassification index. CONCLUSIONS: Coronary computed tomography angiography provides incremental anatomical data to clinical risk assessment to help determine the prognosis of patients after CABG. The CAPS evaluation with CCTA might help identify those patients at highest risk.

Prognostic value of automated vs visual analysis for adenosine stress myocardial perfusion SPECT in patients without prior coronary artery disease: a case-control study.

PURPOSE: We aimed to evaluate the prognostic value of automated quantitative hypoperfusion parameters derived from adenosine stress myocardial perfusion SPECT (MPS) for predicting sudden or cardiac death (CD) in case-controlled patients with suspected coronary artery disease (CAD). METHODS: We considered patients with available adenosine stress Tc-99m sestamibi MPS scans and follow-up information. 81 CD patients from a registry of 428 patients documented by the National Death Index were directly matched in a retrospective case-control design to patients without CD by key clinical parameters (age by deciles, gender, no early revascularization, pre-test likelihood categories, diabetes, and chest pain symptoms). Multivariable analysis of stress MPS total perfusion deficit (STPD) and major clinical confounders were used as predictors of CD. Visual 17-segment summed stress segmental scores (VSSS) obtained by an expert reader, were compared to STPD. RESULTS: CD patients had higher stress hypoperfusion measures compared to controls [STPD: 7.0% vs 3.6% (P < .05), VSSS: 5.3 vs 2.1 (P < .05)]. By univariate analysis, STPD and VSSS have similar predictive power (the areas under receiver operator characteristics curves: STPD = 0.64, VSSS = 0.63; Kaplan-Meier models: χ(2) = 7.59, P = .0059 for STPD and χ(2) = 11.10, P = .0009 for VSSS). The multiple Cox proportional hazards regression models with continuous perfusion measures showed that STPD had similar power to normalized VSSS as a predictor for CD (χ(2) = 4.92; P = .027) vs (χ(2) = 8.90; P = .003). CONCLUSIONS: Quantitative analysis is comparable to expert visual scoring in predicting CD in a case-controlled study.

Increase in epicardial fat volume is associated with greater coronary artery calcification progression in subjects at intermediate risk by coronary calcium score: a serial study using non-contrast cardiac CT.

OBJECTIVE: Epicardial fat volume (EFV) is related to calcified coronary plaques. However, it is unknown whether baseline EFV or changes in EFV affect the progression of coronary artery calcification over time. METHODS: We identified 375 consecutive asymptomatic subjects with an intermediate risk of developing coronary artery disease, who underwent serial non-contrast CT at least 3-5 years apart. Subjects were divided into tertiles of CCS progression (% increase) between the 2 scans. Subjects from the upper tertile (High Progressors) were matched by age and gender to 81 subjects from the lower tertile (Low Progressors). All subjects underwent serial measurements of CCS and EFV. Relationships between EFV and CCS progression, and change in plaque number were examined. RESULTS: At baseline, there was no difference in EFV, and EFV indexed to body surface area (EFVi) between the groups. At follow-up, EFV, EFVi and percent increase in EFVi-change were higher in High Progressors than Low Progressors (EFV, 102 ± 38 cm(3) vs. 90 ± 35 cm(3), p=0.03; EFVi, 50 ± 16cm(3)/m(2) vs. 46 ± 15 cm(3)/m(2), p=0.03; percent increase in EFVi-change, 15 ± 22% vs. 7 ± 20%, p=0.02). On multivariate analysis, after adjusting for conventional risk factors, EFVi increase ≥15% [odds ratio (OR) 2.3, p<0.05], log (baseline CCS) [OR 0.3, p<0.0001] and scan interval time [p=0.003, OR 1.0] were predictive of being a High Progressor. EFVi increase ≥ 15% (ß=3.0, p=0.02) and hypertension (ß=3.1, p=0.01) were independent predictors of number of new calcified plaques on follow-up. CONCLUSION: Increase in EFV is associated with greater progression of coronary artery calcification in intermediate-risk subjects.

Assessment of left ventricular regional wall motion and ejection fraction with low-radiation dose helical dual-source CT: comparison to two-dimensional echocardiography.

BACKGROUND: Electrocardiographic (ECG)-based tube current modulation during cardiac CT reduces radiation exposure but significantly increases noise in parts of the cardiac cycle where tube current is minimized. OBJECTIVE: We evaluated the effect of maximal ECG-based tube current reduction on left ventricular (LV) regional wall motion assessment and ejection fraction (EF) by comparing low-radiation helical dual-source CT (DSCT) to 2-dimensional transthoracic echocardiography (2D-TTE). METHODS: We studied 83 consecutive patients (15 with prior myocardial infarction) who underwent helically acquired DSCT coronary angiography with maximal ECG-based tube current modulation (low-radiation helical DSCT) and 2D-TTE within a 6-month period (median, 1 day), without any change in clinical status between the studies. In all patients, full tube current was applied only at 70% of the R-R interval, with minimal tube current (4% of maximum) in all other parts of the cardiac cycle. Reduced tube voltage (100 kVp) was combined with the maximal dose modulation in 34 patients. DSCT datasets were evaluated by a blinded, experienced cardiologist. Regional wall motion was assessed with the standard 17-segment model, with each segment scored as normal, hypokinetic, akinetic, and dyskinetic. RESULTS: Mean effective radiation dose for the low-radiation helical DSCT was 5.2 ± 1.7 mSv. Regional wall motion was evaluable in all segments on low-radiation helical DSCT. There was excellent agreement of wall motion scoring by low-radiation helical DSCT and 2D-TTE in 1382 of 1411 segments (98%; Cohen's κ value 0.83; 95% confidence interval, 0.76-0.89; P < 0.0001). Mean LVEF was 67.6% ± 10.3% on low-radiation helical DSCT and 61.8% ± 10.3% on 2D-TTE (P < 0.0001). CONCLUSION: Low-radiation dose helical coronary CT angiography with maximal ECG-based tube current modulation is comparable to 2D-TTE for regional wall motion and EF assessment.