Usefulness of the Agatston score = 0 to exclude ischemic cardiomyopathy in patients with heart failure

Quantification of coronary artery calcium has prognostic value and is commonly used in asymptomatic patients. Routine clinical use of coronary artery calcium in other populations remains uncertain. We sought to understand the potential application of the Agatston score in patients with heart failure (HF). For this purpose, 3 populations were identified: (1) patients with an Agatston score equal to 0, (2) patients with high-risk coronary artery disease (CAD) defined as 3-vessel, left main, or 2-vessel disease involving the proximal left anterior descending coronary artery, and (3) patients with HF symptoms and left ventricular (LV) ejection fraction <50%. Excluding patients with HF or LV dysfunction, 738 patients (mean age 52 ± 10 years, 43% men) had an Agatston score equal to 0. Of these, 18 (2%) had obstructive CAD (diameter stenosis ≥50%), 8 (1%) had diameter stenoses ≥70%, and none had high-risk CAD. The 74 patients with high-risk CAD without LV dysfunction had high Agatston scores (mean 895 ± 734, median 716, range 50 to 3,210). In total 153 patients with a history of HF and abnormal ejection fraction were identified. All 13 patients with ischemic cardiomyopathy had Agatston scores >0, whereas 46 of 140 patients (30.1%) with nonischemic causes had an Agatston score equal to 0. An Agatston score equal to 0 identified nonischemic causes with a specificity of 100% (confidence interval 90 to 100) and positive predictive value of 100% (confidence interval 90 to 100). Agatston score equal to 0 had incremental value to pretest probability for CAD. In conclusion, an Agatston score equal to 0 confers a very low likelihood of obstructive CAD, appears to rule out high-risk CAD, and thus may be used to rule out ischemic cardiomyopathy in patients with HF.     

Role of cardiac multidetector computed tomography in the exclusion of ischemic etiology in heart failure patients

Introduction and AimsDifferentiation of ischemic from non-ischemic etiology in heart failure (HF) patients has both therapeutic and prognostic implications. One possible approach to this differentiation is direct visualization of the coronary tree. Multidetector computed tomography (MDCT) has emerged as an alternative to invasive coronary angiography (ICA), but its performance and additional clinical value are still not well validated in patients with left ventricular (LV) dysfunction. We aimed to assess the value of coronary MDCT angiography (CTA) in the exclusion of ischemic etiology in HF patients and to determine whether the Agatston calcium score could be used as a gatekeeper for CTA in this context.MethodsWe retrospectively selected symptomatic HF patients with LV ejection fraction (LVEF) <50%, as assessed by echocardiography, referred for CTA between April 2006 and May 2013. Patients with previously known CAD or valvular disease were excluded. The performance of MDCT in the detection of coronary artery disease (CAD) and/or exclusion of an ischemic etiology for HF was studied. Obstructive CAD was defined as the presence of ≥50% luminal stenosis in at least one epicardial coronary artery as assessed by CTA and was assumed in patients with an Agatston coronary artery calcium (CAC) score >400. In patients referred for ICA, an ischemic etiology was assumed in the presence of ≥75% stenosis in two or more epicardial vessels or ≥75% stenosis in the left main or proximal left anterior descending artery.ResultsDuring this period 100 patients (mean age 57.3±10.5 years, 64% men) with HF and systolic dysfunction were referred for MDCT to exclude CAD. Median effective radiation dose was 4.8 mSv (interquartile range 5.8 mSv). Mean LVEF was 35±7.7% (range 20-48%) and median CAC score was 13 (interquartile range 212). Seven patients were in atrial fibrillation.Almost half of the patients (40%) had no CAC and none of these had significant stenosis on CTA. In an additional group of 33 patients CTA was able to confidently exclude obstructive CAD. Twenty-seven patients were classified as positive for CAD (16 due to CAC >400 and 11 with ≥50% stenosis) and were associated with lower LVEF (p=0.004). Of these, 21 patients subsequently underwent ICA: obstructive CAD was confirmed in nine and only six had criteria for ischemic cardiomyopathy.ConclusionIn our HF population, MDCT was able to exclude an ischemic etiology in 73% of cases in a single test. According to our results the Agatston calcium score may serve as a gatekeeper for CTA in patients with HF, with a calcium score of zero confidently excluding an ischemic etiology.     

64层螺旋CT冠状动脉成像对冠心病诊断的应用价值

目的 通过探讨64层螺旋CT冠状动脉成像(64-SCTCA)对冠心病诊断的应用价值以明确临床上适于该项检查的人群.方法 回顾性分析285例接受64-SCTCA检查、并于4周内接受冠状动脉造影(CAG)检查的冠心病疑诊患者的临床资料.依照冠心病概率Duke模型,将受检者分为冠心病低危(n=80)、中危(n=92)和高危(n=113)3组,以CAG为"金标准",判断64-SCTCA诊断冠心病的准确性以及冠状动脉钙化、不同部位血管节段等因素对诊断准确性的影响.结果 64-SCTCA诊断冠心病的敏感性、特异性、阳性预测值、阴性预测值和诊断准确指\数分别为81.2%、93.3%、68.0%、96.6%和74.5%.冠心病概率Duke模型的低危组、中危组和高危组,其冠心病检出率分别为46.3%、72.8%和82.3%;64-SCTCA在低危组诊断冠心病的敏感性及阳性预测值明显低于中危组和高危组.对于冠状动脉Agatston钙化积分＞400分组,64-SCTCA诊断冠心病的敏感性(95.0%)明显高于0～100分组和101～400分组(77.4%和77.3%,P均＜0.05),特异性(82.2%)明显低于上述两组(94.0%和95.3%,P均＜0.05).其诊断远端血管病变的敏感性、阳性预测值均明显低于近、中段血管(P均＜0.05).结论 64-SCTCA主要适用于冠心病概率Duke模型临床分层的中危人群.其诊断准确性受冠状动脉钙化、病变部位、管腔直径等因素影响.     

Assessment of coronary artery disease using coronary computed tomography angiography in patients with aortic valve stenosis referred for surgical aortic valve replacement

Background

In patients referred for aortic valve replacement (AVR) a pre-surgical assessment of coronary artery disease is mandatory to determine the possible need for additional coronary artery bypass grafting. The diagnostic accuracy of coronary computed tomography angiography (coronary CTA) was evaluated in patients with aortic valve stenosis referred for surgical AVR.

Methods

Between March 2008 and March 2010 a total of 181 consecutive patients were included. All patients underwent pre-surgical coronary CTA (64- or 320-detector CT scanner) and invasive coronary angiography (ICA). The analyses were performed blinded to each other.

Results

The mean ± SD age of the included patients was 71 ± 9 years and 59% were male. The prevalence of significant coronary artery stenosis > 70% by ICA was 36%. Average heart rate during coronary CTA was 65 ± 16 bpm. In a patient based analysis 94% of the patients (171/181) were considered fully evaluable. Coronary CTA had a sensitivity of 68%, a specificity of 91%, a positive predictive value of 81%, and a negative predictive value of 83%. Advanced age, obstructive lung disease, NYHA function class III/IV, and high Agatston score were found to be significantly associated with disagreement between ICA and coronary CTA in univariate analysis.

Conclusion

In patients with aortic valve stenosis referred for surgical AVR the diagnostic accuracy of coronary CTA to identify significant coronary artery disease is moderate. Coronary CTA may be used successfully in a subset of patients with low age, no chronic obstructive lung disease, NYHA function class < III and low coronary Agatston score.     

Prognostic Value of Coronary CT Angiography in Patients With Non–ST-Segment Elevation Acute Coronary Syndromes

BackgroundSeverity and extent of coronary artery disease (CAD) assessed by invasive coronary angiography (ICA) guide treatment and may predict clinical outcome in patients with non–ST-segment elevation acute coronary syndrome (NSTEACS).ObjectivesThis study tested the hypothesis that coronary computed tomography angiography (CTA) is equivalent to ICA for risk assessment in patients with NSTEACS.MethodsThe VERDICT (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography in Patients With Acute Coronary Syndromes) trial evaluated timing of treatment in relation to outcome in patients with NSTEACS and included a clinically blinded coronary CTA conducted prior to ICA. Severity of CAD was defined as obstructive (coronary stenosis ≥50%) or nonobstructive. Extent of CAD was defined as high risk (obstructive left main or proximal left anterior descending artery stenosis and/or multivessel disease) or non–high risk. The primary endpoint was a composite of all-cause death, nonfatal recurrent myocardial infarction, hospital admission for refractory myocardial ischemia, or heart failure.ResultsCoronary CTA and ICA were conducted in 978 patients. During a median follow-up time of 4.2 years (interquartile range: 2.7 to 5.5 years), the primary endpoint occurred in 208 patients (21.3%). The rate of the primary endpoint was up to 1.7-fold higher in patients with obstructive CAD compared with in patients with nonobstructive CAD as defined by coronary CTA (hazard ratio [HR]: 1.74; 95% confidence interval [CI]: 1.22 to 2.49; p = 0.002) or ICA (HR: 1.54; 95% CI: 1.13 to 2.11; p = 0.007). In patients with high-risk CAD, the rate of the primary endpoint was 1.5-fold higher compared with the rate in those with non–high-risk CAD as defined by coronary CTA (HR: 1.56; 95% CI: 1.18 to 2.07; p = 0.002). A similar trend was noted for ICA (HR: 1.28; 95% CI: 0.98 to 1.69; p = 0.07).ConclusionsCoronary CTA is equivalent to ICA for the assessment of long-term risk in patients with NSTEACS. (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography in Patients With Acute Coronary Syndromes [VERDICT]; NCT02061891)     

Prognostic Value of Stress CMR in Symptomatic Patients With Coronary Stenosis on CCTA

BackgroundNoninvasive functional imaging is often performed in patients with obstructive coronary artery disease (CAD) on coronary computed tomography angiography (CTA). However, the prognostic value of stress cardiac magnetic resonance (CMR) is unknown in patients with coronary stenosis of unknown significance on coronary CTA.ObjectivesThis study assessed the prognostic value of stress CMR in symptomatic patients with obstructive CAD of unknown significance on coronary CTA.MethodsBetween 2008 and 2020, consecutive symptomatic patients without known CAD referred for coronary CTA were screened. Patients with obstructive CAD (at least 1 ≥50% stenosis on coronary CTA) were further referred for stress CMR and followed for the occurrence of major adverse cardiovascular events (MACEs), defined as cardiovascular death or nonfatal myocardial infarction.ResultsOf 2,210 patients who completed CMR, 2,038 (46.5% men; mean age 69.8 ± 12.2 years) completed follow-up (median 6.8 years; IQR: 5.9-9.2 years); 281 experienced a MACE (13.8%). Inducible ischemia and late gadolinium enhancement (LGE) were significantly associated with MACEs (HR: 4.51 [95% CI: 3.55-5.74], and HR: 3.32 [95% CI: 2.55-4.32], respectively; P < 0.001). In multivariable Cox regression, the number of segments with >70% stenosis, with noncalcified plaques and the number of vessels with obstructive CAD were prognosticators (P < 0.001). The presence of inducible ischemia and LGE were independent predictors of MACEs (HR: 3.97 [95% CI: 3.43-5.13]; HR: 2.30 [95% CI: 1.52-3.33]; P < 0.001). After adjustment, stress CMR showed the best improvement in model discrimination and reclassification above traditional risk factors and coronary CTA (C-statistic improvement: 0.04; net reclassification improvement = 0.421; integrative discrimination index = 0.047).ConclusionsIn symptomatic patients with obstructive CAD of unknown significance on coronary CTA, stress CMR had incremental prognostic value to predict MACEs.     

Association of cardiac events with coronary artery disease detected by 64-slice or greater coronary CT angiography: A systematic review and meta-analysis

Background

The value of ≥ 64-slice coronary CT angiography (CCTA) to determine odds of cardiac death or non-fatal myocardial infarction (MI) needs further clarification.

Methods

We performed a systematic review and meta-analysis using publications reporting events/severity of coronary artery disease (CAD) in patients with suspected CAD undergoing CCTA. Patients were divided into: no CAD, non-obstructive CAD (maximal stenosis < 50%), and obstructive CAD (≥ 50% stenosis). Odds ratios with 95% confidence intervals were calculated using a fixed or random effects model. Heterogeneity was assessed using the I² index.

Results

We included thirty-two studies comprising 41,960 patients with 363 all-cause deaths (15.0%), 114 cardiac deaths (4.7%), 342 MI (14.2%), 69 unstable angina (2.8%), and 1527 late revascularizations (63.2%) over 1.96 (SD 0.77) years of follow-up. Cardiac death or MI occurred in 0.04% without, 1.29% with non-obstructive, and 6.53% with obstructive CAD. OR for cardiac death or MI was: 14.92 (95% CI, 6.78 to 32.85) for obstructive CAD, 6.41 (95% CI, 2.44 to 16.84) for non-obstructive CAD versus no CAD, and 3.19 (95% CI, 2.29 to 4.45) for non-obstructive versus obstructive CAD and 6.56 (95% CI, 3.07 to 14.02) for no versus any CAD. Similar trends were noted for all-cause mortality and composite major adverse cardiovascular events.

Conclusions

Increasing CAD severity detected by CCTA is associated with cardiac death or MI, all-cause mortality, and composite major adverse cardiovascular events. Absence of CAD is associated with very low odds of major adverse events, but non-obstructive disease significantly increases odds of cardiac adverse events in this follow-up period.     

Coronary artery disease among asymptomatic diabetic and nondiabetic patients undergoing coronary computed tomography angiography

OBJECTIVES: The aim of this study was to determine the prevalence and severity of coronary artery disease (CAD) and the plaque composition in asymptomatic diabetic and nondiabetic patients undergoing coronary computed tomography angiography (CCTA). BACKGROUND: CAD is the major cause of death among patients with diabetes. The true prevalence of CAD in asymptomatic diabetic patients, however, remains unknown. MATERIALS AND METHODS: A total of 328 consecutive patients (each with at least one risk factor or abnormal stress-test results) were referred for cardiac evaluation, 42 with diabetes and 286 without diabetes, all asymptomatic for cardiac-related symptoms. Groups were matched for age, sex, and CAD risk factors. CAD was defined as coronary atherosclerosis, with obstructive or nonobstructive lesions. CCTA was performed and findings compared between patients with diabetes and those without. RESULTS: CAD was present in 39 (93%) diabetic patients and in 211 (73%) nondiabetic patients (P=0.006). Obstructive CAD was more common in diabetic patients than in nondiabetic patients (29 vs. 6.6%, respectively; P<0.0001). In diabetic patients, more coronary segments with atherosclerosis per patient were detected (5.5 segments/patient vs. 2.8 segments/patient in nondiabetics; P<0.0001). The total Agatston score was significantly higher in diabetic patients vs. nondiabetic patients (370+/-96 and 79.9+/-16, respectively; P<0.0001). CONCLUSION: Our results indicate a high prevalence (93%) of CAD in asymptomatic diabetic patients with either nonobstructive or obstructive lesions. CCTA may be a useful imaging modality for selecting patients at high risk who would benefit most from further evaluation for subclinical ischemia.     

Predictive values of Framingham risk and coronary artery calcium scores in the detection of obstructive CAD in patients with normal SPECT

A subgroup of patients with normal stress myocardial perfusion imaging (MPI) have obstructive coronary artery disease (CAD) on coronary computed tomographic angiography (CCTA). A retrospective study was performed to identify factors associated with obstructive CAD in patients with normal MPI. Bivariate differences between patients with obstructive (>50% stenosis) and nonobstructive (<50% stenosis) CAD were assessed. Of the 105 patients with normal MPI, 42 (40%) had obstructive CAD on CCTA. After a multivariable logistic regression analysis increased Framingham risk scores ([FRS] ≥10%) and coronary artery calcium scores ([CACS] >100 Agatston Units [AU]) were independently associated with obstructive CAD (P = .006 and P < .0001, respectively). Patients with normal MPI had 13 times and 98 times higher odds of having obstructive CAD if they had a FRS ≥10% versus <10% and CACS >100 AU versus ≤100 AU, respectively. Increased FRS and CACS may stratify patients who may benefit from further evaluation for significant CAD despite normal MPI.     

Diagnostic value of coronary artery calcium scoring in low-intermediate risk patients evaluated in the emergency department for acute coronary syndrome

Early and accurate triage of patients with possible ischemic chest pain remains challenging in the emergency department because current risk stratification techniques have significant cost and limited availability. The aim of this study was to determine the diagnostic value of the coronary artery calcium score (CACS) for the detection of obstructive coronary artery disease (CAD) in low- to intermediate-risk patients evaluated in the emergency department for suspected acute coronary syndromes. A total of 225 patients presenting to the emergency department with acute chest pain and Thrombolysis In Myocardial Infarction (TIMI) scores <4 who underwent non-contrast- and contrast-enhanced coronary computed tomographic angiography were included. CACS was calculated from the noncontrast scan using the Agatston method. The prevalence of obstructive CAD (defined from the contrast scan as ≥ 50% maximal reduction in luminal diameter in any segment) was 9% and increased significantly with higher scores (p <0.01 for trend). CACS of 0 were observed in 133 patients (59%), of whom only 2 (1.5%) had obstructive CAD. The diagnostic accuracy of CACS to detect obstructive CAD was good, with an area under the receiver-operating characteristic curve of 0.88 and a negative predictive value of 99% for a CACS of 0. In a multivariate model, CACS was independently associated with obstructive CAD (odds ratio 7.01, p = 0.02) and provided additional diagnostic value over traditional CAD risk factors. In conclusion, CACS appears to be an effective initial tool for risk stratification of low- to intermediate-risk patients with possible acute coronary syndromes, on the basis of its high negative predictive value and additive diagnostic value.     

Influence of coronary computed tomographic angiography on patient treatment and prognosis in patients with suspected stable angina pectoris

We evaluated the influence of coronary computed tomographic angiography (CTA) as a first-line diagnostic test on patient treatment and prognosis. A total of 1,055 consecutive patients with suspected stable angina pectoris (mean age 55 ± 10 years, 56% women) and a low to intermediate pretest likelihood of coronary artery disease (CAD) were included in the present study. The patients were followed for a median of 18 months. The use of downstream diagnostic testing and medical therapy after CTA were recorded. The CTA result was normal in 49%, and nonobstructive and obstructive CAD (≥50% stenosis) was demonstrated in 31% and 15% of the patients, respectively. Coronary CTA was inconclusive in 5% of the patients. The use of antiplatelet therapy decreased with normal findings from CTA, and the use of antiplatelet and lipid-lowering agents increased in patients with CAD. Additional testing was performed in 2% of patients with normal CTA findings and in 7% and 82% of patients with nonobstructive or obstructive CAD, respectively. No patients without CAD, 0.9% of patients with nonobstructive CAD, and 1.9% of patients with obstructive CAD met the primary end point (cardiovascular death and myocardial infarction, p = 0.008). No patients without CAD, 1.5% of patients with nonobstructive CAD, and 30% patients with obstructive CAD met the secondary end point (cardiovascular death, myocardial infarction, and coronary revascularization, p <0.0001). In conclusion, in patients suspected of having angina, the findings from CTA influence patient treatment without resulting in excessive additional testing. Coronary CTA provides important prognostic information, with excellent intermediate-term outcomes in patients with normal CTA findings.     

Evidenzbasierter Einsatz von Kardio-MR und Kardio-CT in der Primärdiagnostik der stabilen koronaren Herzkrankheit unter besonderer Berücksichtigung des Disease-Management-Programms (DMP) KHK und der Nationalen Versorgungsleitlinie

BACKGROUND AND PURPOSE: Despite all the progress made in diagnosis and treatment, cardiovascular diseases remain the no. 1 cause of death worldwide. In 2005, 27.9% of males and 24.1% of females (eight times more than for mammary carcinoma) in Germany died of coronary artery disease (CAD). Although mortality rates following acute myocardial infarction have considerably dropped, morbidity has increased--people are getting older, but they are getting older sick. The resulting need for reduction of CAD morbidity can only be achieved by truly early detection of patients at high coronary risk before occurrence of a coronary event. Modern imaging techniques like cardiac magnetic resonance (MR) and cardiac computed tomography (CT) are being increasingly utilized. The goal of this review is the practical application of evidence-based recommendations by relevantly and cost-effectively implementing cardiac MR and cardiac CT with special attention to current national and international guidelines and recommendations. THE PATIENT WITH STABLE CHEST PAIN: The primary objective here is to ascertain if the described symptoms can be attributed to a stenosing CAD with inducible myocardial ischemia or if they are effected by extracardial sources. As always, patients' history, examination findings and the stress ECG play the major roles. The conventional approach prescribes that an abnormal resting ECG compromising the interpretation of a stress ECG, should immediately be followed by an imaging ischemia diagnosis technique, like stress echocardiography, myocardial scintigraphy or cardiac MR (recommendation I B). This also holds true when a stress ECG is assessable and the probability of a stenosing CAD is between 10% and 90% (recommendation I B or "appropriate"). Alternatively, "modern" procedures allow imaging ischemia diagnosis to be replaced by noninvasive coronary angiography using a CTA (recommendation IIa B). If the image quality by CTA is assessable (free of artifacts and no disruptive calcified plaques) and no coronary stenosis can be found, the coronary diagnosis process may at this point be terminated, avoiding superfluous cardiac catheterizations. If the CTA shows the possibility of a higher-grade coronary stenosis, a cardiac catheterization examination with stand-by PCI (percutaneous coronary intervention) can be performed. THE ASYMPTOMATIC PREVENTION PATIENT: The prim ary objective in cardiovascular primary prevention is the avoidance of a first myocardial infarction and/or a first stroke. Current guidelines for prevention of cardiovascular diseases recommend administration of acetylsalicylic acid (ASA) and a statin when risk>20%/10 years (recommendation I A). The coronary calcium score has a strong predictive power which is independent of conventional risk factors and thus offers the most relevant information in addition to Framingham, PROCAM or ESC scores regarding coronary risk. For patients initially showing "intermediate" coronary risk (10-20%), guidelines suggest the determination of the coronary calcium score, which leads to better risk assessment and to identification of patients needing more aggressive lipid lowering (recommendation IIb B). Thus, the cardiac CT, on the one hand, aims the intense risk reduction needed in primary prevention to the high-risk patients, on the other hand, it avoids "superfluous" cardiac catheterizations, unnecessary statin therapies and potentially harmful ASA administrations. However, the proof of coronary calcium must not be confused with the presence of coronary artery stenoses: a positive calcium score in an asymptomatic person does not by itself indicate the need for a cardiac catheterization.     

Comparison of sensitivity, specificity, positive predictive value, and negative predictive value of stress testing versus 64-multislice coronary computed tomography angiography in predicting obstructive coronary artery disease diagnosed by coronary angiography

Sixty-four-multislice coronary computed tomographic angiography (CTA) and coronary angiography were performed in 145 patients (mean age 67 +/- 10 years), and stress testing was performed in 47 of these patients to determine the sensitivity, specificity, positive predictive value, and negative predictive value of coronary CTA and of stress testing in diagnosing obstructive coronary artery disease (CAD) in patients with suspected CAD. In 145 patients, coronary CTA had 98% sensitivity, 74% specificity, 90% positive predictive value, and 94% negative predictive value in diagnosing obstructive CAD. In 47 patients, stress testing had 69% sensitivity, 36% specificity, 78% positive predictive value, and 27% negative predictive value for diagnosing obstructive CAD, whereas coronary CTA had 100% sensitivity, 73% specificity, 92% positive predictive value, and 100% negative predictive value for diagnosing obstructive CAD. In conclusion, coronary CTA has better sensitivity, specificity, positive predictive value, and negative predictive value than stress testing in diagnosing obstructive CAD.     

Heterogenous Distribution of Risk for Cardiovascular Disease Events in Patients With Stable Ischemic Heart Disease

ObjectivesThe authors sought to assess the distribution of 5-year risk of cardiovascular disease (CVD) events (myocardial infarction, revascularizations, ischemic stroke) and death among symptomatic patients with varying degrees of coronary artery disease (CAD) ascertained from computed tomography angiography (CTA).BackgroundCTA is used increasingly as the first-line test for evaluating patients with symptoms suggestive of CAD. This creates the daily clinical challenge of best using the information available from CTA to guide appropriate downstream allocation of preventive treatments.MethodsAmong 21,275 patients from the Western Denmark Heart Registry, the authors developed a model predicting 5-year risk for CVD and death based on traditional risk factors and CAD severity. Only events occurring >90 days after CTA were included.ResultsDuring a median follow-up of 4.2 years, 1,295 CVD events and deaths occurred. The median 5-year risk for events was 4% (interquartile range: 3% to 8%), and ranged from <5% to >50% in individual patients. The degree of CAD severity was the strongest risk factor; however, traditional risk factors also contributed significantly to risk. Thus, risk distributions in patients with varying degree of CAD overlapped considerably, and patients with extensive nonobstructive CAD could have higher estimated risk than patients with obstructive CAD (stenosis >50%). Among patients with obstructive CAD, 12% had 5-year risk <10% whereas 24% had risk >20%. A similar large overlap in risk was found when revascularizations were excluded from the endpoint.ConclusionsThe 5-year risk for CVD events and death varies substantially in symptomatic patients undergoing CTA, even in the presence of obstructive CAD. These results provide support for individual risk assessment to improve potential benefit when allocating preventive therapies following CTA.     

Coronary calcification, coronary disease risk factors, C-reactive protein, and atherosclerotic cardiovascular disease events: the St. Francis Heart Study

OBJECTIVES: The purpose of this study was to determine the prognostic accuracy of electron beam computed tomographic (CT) scanning of the coronary arteries and the relationship of coronary calcification to standard coronary disease risk factors and C-reactive protein (CRP) in the prediction of atherosclerotic cardiovascular disease (ASCVD) events in apparently healthy middle-age persons. BACKGROUND: As a screening test for coronary artery disease (CAD), electron beam CT scanning remains controversial. METHODS: In a prospective, population-based study, 4,903 asymptomatic persons age 50 to 70 years underwent electron beam CT scanning of the coronary arteries. RESULTS: At 4.3 years, follow-up was available in 4,613 participants (94%), and 119 had sustained at least one ASCVD event. Subjects with ASCVD events had higher baseline coronary calcium scores (median [interquartile range], Agatston method) than those without events: 384 (127, 800) versus 10 (0, 86) (p < 0.0001). For coronary calcium score threshold > or = 100 versus < 100, relative risk (95% confidence interval) was 9.6 (6.7 to 13.9) for all ASCVD events, 11.1 (7.3 to 16.7) for all CAD events, and 9.2 (4.9 to 17.3) for non-fatal myocardial infarction and death. The coronary calcium score predicted CAD events independently of standard risk factors and CRP (p = 0.004), was superior to the Framingham risk index in the prediction of events (area under the receiver-operating characteristic curve of 0.79 +/- 0.03 vs. 0.69 +/- 0.03, p = 0.0006), and enhanced stratification of those falling into the Framingham categories of low, intermediate, and high risk (p < 0.0001). CONCLUSIONS: The electron beam CT coronary calcium score predicts CAD events independent of standard risk factors, more accurately than standard risk factors and CRP, and refines Framingham risk stratification.     

Accelerated subclinical coronary atherosclerosis in patients with familial hypercholesterolemia

Objectives

We determined the extent, severity, distribution and type of coronary plaques in cardiac asymptomatic patients with familial hypercholesterolemia (FH) using computed tomography (CT).

Background

FH patients have accelerated progression of coronary artery disease (CAD) with earlier major adverse cardiac events. Non-invasive CT coronary angiography (CTCA) allows assessing the coronary plaque burden in asymptomatic patients with FH.

Materials and methods

A total of 140 asymptomatic statin treated FH patients (90 men; mean age 52 ± 8 years) underwent CT calcium scoring (Agatston) and CTCA using a Dual Source CT scanner with a clinical follow-up of 29 ± 8 months. The extent, severity (obstructive or non-obstructive plaque based on >50% or <50% lumen diameter reduction), distribution and type (calcified, non-calcified, or mixed) of coronary plaque were evaluated.

Results

The calcium score was 0 in 28 (21%) of the patients. In 16% of the patients there was no CT-evidence of any CAD while 24% had obstructive disease. In total 775 plaques were detected with CT coronary angiography, of which 11% were obstructive. Fifty four percent of all plaques were calcified, 25% non-calcified and 21% mixed. The CAD extent was related to gender, treated HDL-cholesterol and treated LDL-cholesterol levels. There was a low incidence of cardiac events and no cardiac death occurred during follow-up.

Conclusion

Development of CAD is accelerated in intensively treated male and female FH patients. The extent of CAD is related to gender and cholesterol levels and ranges from absence of plaque in one out of 6 patients to extensive CAD with plaque causing >50% lumen obstruction in almost a quarter of patients with FH.     

PET心肌血流绝对定量评估冠状动脉微血管疾病的临床研究

目的比较非阻塞及阻塞性冠状动脉(冠脉)疾病患者的冠脉微血管疾病(CMVD)发生情况。方法回顾性分析2015年12月至2019年12月在山西医科大学附属第一医院成功完成13N-氨水正电子发射计算机断层显像(PET)心肌血流绝对定量检查并在PET检查90 d内完成冠脉造影或CTA的97例疑诊CMVD患者,根据造影及CTA结果将患者分为非阻塞组(72例,3支冠脉均不存在狭窄≥50%的病变)和阻塞组(25例,至少存在1支冠脉狭窄≥50%,且至少存在1支冠脉狭窄<50%),以冠脉血流储备(CFR)<2.90且负荷心肌血流量(SMBF)<2.17 ml·min-1·g-1为CMVD的判定标准,从血管及患者层面分析两组患者非阻塞性冠脉的CMVD发生情况,并比较两组间发生CMVD的冠脉支配区的静息心肌血流量(RMBF)、SMBF及CFR。结果在血管层面,阻塞组非阻塞性冠脉存在CMVD的比例高于非阻塞组[47.1%(16/34)比25.5%(55/216),χ2=6.738,P=0.009]。在患者层面,两组发生CMVD的比例差异无统计学意义[(44%(11/25)比33.3%(24/72),χ2=0.915,P=0.339]。两组间发生CMVD的冠脉支配区的RMBF[(0.83±0.14)ml·min-1·g-1比(0.82±0.17)ml·min-1·g-1]、SMBF[(2.13±0.60)ml·min-1·g-1比(1.91±0.50)ml·min-1·g-1]及CFR(2.59±0.66比2.36±0.47)比较,差异均无统计学意义(P>0.05)。结论非阻塞与阻塞性冠脉疾病患者的非阻塞性冠脉均可存在CMVD,后者的CMVD检出率更高,两者CMVD的严重程度基本一致。     

Association of coronary atherosclerosis detected by multislice computed tomography and traditional risk-factor assessment

Framingham risk score is an office-based tool used for long-term coronary heart disease risk stratification. Most acute coronary events occur in association with proximal nonobstructive atherosclerotic plaque. Multislice computed tomography detects both obstructive coronary artery disease (CAD) and proximal atherosclerotic plaque with high accuracy. The association of Framingham risk score with obstructive CAD and proximal atherosclerotic plaque was tested. Coronary multislice computed tomography was performed in 295 patients (61% men, mean age 54 +/- 13 years) without documented CAD referred for evaluation of cardiac symptoms. Framingham risk score was computed and patients were stratified according to 10-year risk (n = 213 [72%] low, n = 74 [25%] intermediate, and n = 8 [3%] high). Obstructive CAD was defined as > or =50% stenosis in > or =1 epicardial coronary artery. Proximal atherosclerotic plaque was defined as calcified or noncalcified plaque in the left main or proximal left anterior descending artery. In the low- and intermediate-Framingham risk score groups, there was a high frequency of proximal atherosclerotic plaque (44% and 75%) and obstructive CAD (16% and 34%), although both findings were more prevalent in the high-Framingham risk score group (63% for atherosclerotic plaque, 88% for obstructive CAD), respectively. Proximal atherosclerotic plaque was noncalcified in approximately 13 of patients. In women (n = 114) and younger (<55 years) patients (n = 148), most (93% and 91%, respectively) had a low Framingham risk score. There were 48 women and 51 younger patients with proximal atherosclerotic plaque, of whom only 40% (in each group) were on statin therapy. In conclusion, of patients with a low and intermediate Framingham risk score, a significant proportion had proximal atherosclerotic plaque or obstructive CAD.     

Myocardial perfusion by CT versus hybrid imaging

Coronary computed tomography angiography (CTA) is a reliable diagnostic test for the anatomic diagnosis of obstructive coronary artery disease (CAD). Although coronary CTA shows high sensitivity and negative predictive value for detecting stenosis greater than or equal to 50% diameter, it is limited in its ability to diagnose myocardial ischemia. Advances in computed tomography (CT) technology alone and technology that hybridizes CT with single-photon emission CT and positron emission tomography allow for the combined anatomic and physiologic diagnosis of CAD. This article summarizes these combined technologies, emphasizing the merits and limitations of each technology and their clinical implications.     

An algorithm for noninvasive identification of angiographic three-vessel and/or left main coronary artery disease in symptomatic patients on the basis of cardiac risk and electron-beam computed tomographic calcium scores

ObjectivesWe sought to model an algorithm for noninvasive identification of angiographically obstructive three-vessel and/or left main disease based on conventional cardiac risk assessment and site and extent of coronary calcium determined by electron-beam computed tomography (EBCT).BackgroundSuch an algorithm would greatly facilitate clinical triage in symptomatic patients with no previous diagnosis of coronary artery disease (CAD).MethodsWe examined 291 patients with suspected, but not previously diagnosed, CAD who underwent coronary angiography for clinical indications. Cardiac risk factors were determined as defined by the National Cholesterol Education Program. An EBCT scan was performed in all patients, and a coronary calcium score (Agatston method) was computed. Total per-patient calcium scores and separate scores for the major coronary arteries were generated. These scores were also analyzed for localization of coronary calcium in the more distal versus proximal tomographic sections. These parameters and the risk factors were considered for the model described in the following section.ResultsSixty-eight patients (23%) had angiographic three-vessel and/or left main CAD. Multiple logistic regression analysis determined male sex, presence of diabetes and left anterior descending (LAD) and circumflex (LCx) coronary calcium scores, independent from more distal calcium localization, as independent predictors for identification of three-vessel and/or left main CAD. Based on this four variable model, a simple noninvasive index (NI) was constructed as the following: log_e(LAD score) + log_e(LCx score) + 2[if diabetic] + 3[if male]. Receiver operating characteristic curve analysis for this NI yielded an area under the curve of 0.88 ± 0.03 (p < 0.0001) for separating patients with, versus without, angiographic three-vessel and/or left main CAD. Various NI cutpoints demonstrated sensitivities from 87–97% and specificities from 46–74%. The NI values >14 increased the probability of angiographic three-vessel and/or left main CAD from 23% (pretest) to 65–100% (posttest), and NI values <10 increased the probability of no three-vessel and/or left main CAD from 77% (pretest) to 95–100% (posttest).ConclusionsOn the basis of a simple algorithm (“noninvasive index”), EBCT calcium scanning in conjunction with risk factor analysis can rule in or rule out angiographically severe disease, i.e., three-vessel and/or left main CAD, in symptomatic patients.