Search

Patients with myocardial bridges (MBs) have a higher prevalence of atherosclerosis. Wall shear stress (WSS) has previously been correlated with plaque in coronary artery disease patients, but such correlations have not been investigated in symptomatic MB patients. The aim of this paper was to use a multi-scale computational fluid dynamics (CFD) framework to simulate hemodynamics in MB patient, and investigate the co-localization of WSS and plaque.We identified N = 10 patients from a previously reported cohort of 50 symptomatic MB patients, all of whom had plaque in the proximal vessel. Dynamic 3D models were reconstructed from coronary computed tomography angiography (CCTA), intravascular ultrasound (IVUS) and catheter angiograms. CFD simulations were performed to compute WSS proximal to, within and distal to the MB. Plaque was quantified from IVUS images in 2 mm segments and registered to CFD model. Plaque area was compared to absolute and patient-normalized WSS.WSS was lower in the proximal segment compared to the bridge segment (6.1 ± 2.9 vs. 16.0 ± 7.1 dynes/cmWSS may be obtained non-invasively in MB patients and provides a surrogate marker of plaque area. Using CFD, it may be possible to non-invasively assess the extent of plaque area, and identify patients who could benefit from frequent monitoring or medical management.

Myocardial bridge (MB) of the left anterior descending (LAD) coronary artery occurs in approximately 25% of the population. When medical therapy fails in patients with a symptomatic, hemodynamically significant MB, MB unroofing represents the optimal surgical management. Here, we evaluated minimally invasive MB unroofing in selected patients compared with sternotomy.MB unroofing was performed in 141 adult patients by sternotomy on-pump (ST-on, n = 40), sternotomy off-pump (ST-off, n = 62), or minithoracotomy off-pump (MT, n = 39). Angina symptoms were assessed preoperatively and 6 months postoperatively using the Seattle Angina Questionnaire. Matching included all MT patients and 31 ST-off patients with similar MB characteristics, no previous cardiac operations or coronary interventions, and no concomitant procedures.MT patients tended to have a shorter MB length than ST-on and ST-off patients (2.57 vs 2.93 vs 3.09 cm, P = .166). ST-on patients had a longer hospital stay than ST-off and MT patients (5.0 vs 4.0 vs 3.0 days, P .001), and more blood transfusions (15.2% vs 0.0% vs 2.6%, P = .002). After matching, MT patients had a shorter hospital stay than ST-off patients (3.0 vs 4.0 days, P = .005). No deaths or major complications occurred in any group. In all groups, MB unroofing yielded significant symptomatic improvement regarding physical limitation, angina stability, angina frequency, treatment satisfaction, and quality of life.We report our single-center experience of off-pump minimally invasive MB unroofing, which may be safely performed in carefully selected patients, yielding dramatic improvements in angina symptoms at 6 months after the operation.

Atheromatous plaques tend to form in the coronary segments proximal to a myocardial bridge (MB), but the mechanism of this occurrence remains unclear. This study evaluates the relationship between blood flow perturbations and plaque formation in patients with an MB.A total of 92 patients with an MB in the mid left anterior descending artery (LAD) and 20 patients without an MB were included. Coronary angiography, intravascular ultrasound, and coronary physiology measurements were performed. A moving-boundary computational fluid dynamics algorithm was used to derive wall shear stress (WSS) and peak residence time (PRT). Patients with an MB had lower WSS (0.46 ± 0.21 vs. 0.96 ± 0.33 Pa, p 0.001) and higher maximal plaque burden (33.6 ± 15.0 vs. 14.2 ± 5.8%, p 0.001) within the proximal LAD compared to those without. Plaque burden in the proximal LAD correlated significantly with proximal WSS (r = -0.51, p 0.001) and PRT (r = 0.60, p 0.001). In patients with an MB, the site of maximal plaque burden occurred 23.4 ± 13.3 mm proximal to the entrance of the MB, corresponding to the site of PRT.Regions of low WSS and high PRT occur in arterial segments proximal to an MB, and this is associated with the degree and location of coronary atheroma formation.

Spontaneous coronary artery dissection is an increasingly recognized cause of acute coronary syndrome in younger patients. Management remains challenging and involves weighing the benefits of revascularization with the potential to worsen the dissection. We present a case of spontaneous coronary artery dissection with the superimposed complexity of an anomalous intramural coronary artery. (Level of Difficulty: Intermediate.), Graphical abstract, Spontaneous coronary artery dissection is an increasingly recognized cause of acute coronary syndrome in younger patients. Management remains challenging…

Background: Despite optimal medical therapy, a myocardial bridge (MB) can cause life-limiting symptoms in a subset of patients. While surgical unroofing has been shown to improve MB-derived refractory angina, diagnostic indices of clinical symptoms and predictors of improvement following surgery are yet to be elucidated. Methods: To identify determinants of preoperative symptoms and their improvement following the surgery, preoperative intravascular ultrasound (IVUS) and coronary computed tomography angiography were evaluated in 111 patients with symptomatic MB who underwent surgical unroofing. The primary outcome was the Seattle Angina Questionnaire summary score (the average of physical limitation, angina frequency, and quality of life scores). In addition to standard anatomic variables of an MB, degrees of extrinsic vessel restriction at end-diastole and end-systole were evaluated by IVUS using the ratio of measured vessel area and interpolated reference at the maximum compression site. The diastolic restriction was also evaluated by coronary computed tomography angiography as the maximum lumen area stenosis within the MB segment. Results: Even during diastole, IVUS revealed vessel restriction in 87% of the patients. Among the variables evaluated, vessel restriction was the strongest parameter correlating with the preoperative Seattle Angina Questionnaire summary score, particularly when assessed in diastole ( P P =0.006 in coronary computed tomography angiography). The diastolic restriction by IVUS also showed a weak, but significant correlation with improvement in Seattle Angina Questionnaire summary score 6 months after surgery ( P =0.004). Conclusions: Restricted arterial relaxation in diastole, rather than the degree of systolic compression or extent of an MB, seems to be the primary determinant of clinical symptoms and improvement in quality of life following surgical unroofing.

Anomalous aortic origin of the right coronary artery (AAORCA) may cause ischemia and sudden death. However, the specific anatomic indications for surgery are unclear, so dobutamine-stress instantaneous wave-free ratio (iFR) is increasingly used. Meanwhile, advances in fluid-structure interaction (FSI) modeling can simulate the pulsatile hemodynamics and tissue deformation. We sought to evaluate the feasibility of simulating the resting and dobutamine-stress iFR in AAORCA using patient-specific FSI models and to visualize the mechanism of ischemia within the intramural geometry and associated lumen narrowing.We developed 6 patient-specific FSI models of AAORCA using SimVascular software. Three-dimensional geometries were segmented from coronary computed tomography angiography. Vascular outlets were coupled to lumped-parameter networks that included dynamic compression of the coronary microvasculature and were tuned to each patient's vitals and cardiac output.All cases were interarterial, and 5 of 6 had an intramural course. Measured iFRs ranged from 0.95 to 0.98 at rest and 0.80 to 0.95 under dobutamine stress. After we tuned the distal coronary resistances to achieve a stress flow rate triple that at rest, the simulations adequately matched the measured iFRs (r = 0.85, root-mean-square error = 0.04). The intramural lumen remained narrowed with simulated stress and resulted in lower iFRs without needing external compression from the pulmonary root.Patient-specific FSI modeling of AAORCA is a promising, noninvasive method to assess the iFR reduction caused by intramural geometries and inform surgical intervention. However, the models' sensitivity to distal coronary resistance suggests that quantitative stress-perfusion imaging may augment virtual and invasive iFR studies.

Background: Advances in the management of patients with congenital heart disease (CHD) have made survival to adulthood an expectation. Although the literature is limited, existing evidence suggests that adult co-morbidities may be at least as prevalent in patients with CHD, if not more so, than in an age-matched general population. The presence of these co-morbidities in combination with underlying CHD likely places these patients at increased risk for early mortality. Thus, we sought to determine the predicted 10-year mortality risk in a cohort of adults with CHD. Methods: In this single center study, we administered a survey to patients ≥18 years of age with CHD to assess their 10-year mortality risk. Results: A total of 406 patients agreed to participate. The median age was 41.8 ± 15.3 years, and 58% were female. The average predicted 10-year mortality for the CHD cohort was 13.7 ± 15.8%. For CHD patients ≥50 years of age, the average 10-year mortality risk was 29.8 ± 3.0% compared to 26.1% ± 0.2% in the general population (p

Introduction: Myocardial bridging (MB) has been shown to cause significant clinical symptoms or adverse cardiac events in patients with no obstructive coronary artery disease. In contrast to medical therapy or stent placement with controversial efficacy, surgical unroofing (supra-arterial myotomy) of MB is considered to directly address the pathology with durable normalization of the altered hemodynamics. In this context, preoperative IVUS assessment can provide a precise map of the MB to guide the unroofing procedure, but it remains unclear if any IVUS parameter is related to the efficacy of this treatment. Methods: We evaluated 94 consecutive patients who underwent MB unroofing with serial (preoperative and 6-month follow-up) angina assessments using the Seattle Angina Questionnaire (SAQ). The primary outcome was the SAQ summary score, obtained by averaging the scores of physical limitation, angina frequency, and quality of life. Preoperative IVUS determined total MB length, halo thickness, arterial compression rate, maximal plaque burden upstream of MB, and septal branches originating in the tunneled LAD segment. Results: In all cases, preoperative IVUS successfully offered a geographic MB map with quantitative characteristics: MB length = 27.5 (20.2 to 40.3) mm, halo thickness = 0.54 (0.41 to 0.75) mm, arterial compression rate = 34 (26 to 43)%, and plaque burden = 34 (20 to 46)% [median (range) for all]. MB unroofing resulted in significant symptomatic improvements across all scales of SAQ (p Conclusions: IVUS-guided surgical unroofing safely and effectively achieved significant symptomatic improvements in patients with MB, regardless of the morphologic or morphometric MB characteristics assessed by preoperative IVUS.

Introduction: Anomalous coronaries are associated with ischemia and sudden death, but the recommendation to undergo surgery is often uncertain, especially for asymptomatic individuals with an anomalous aortic origin of the right coronary artery (AAORCA). For risk stratification, dobutamine-stress instantaneous wave-free ratio (iFR) is increasingly used. Meanwhile, advances in fluid-structure interaction (FSI) modeling have enabled the simultaneous simulation of blood flow and tissue deformation that may elucidate the mechanism of ischemia in AAORCA. Hypothesis: We hypothesized that the iFR simulated by patient-specific FSI models of AAORCA correlates with the measured iFR at rest and dobutamine-stress, and the hemodynamic mechanism is mainly due to the intramural geometry. Methods: Using the Simvascular software package, we constructed 6 FSI models of the AAORCA which encompassed the aortic root, the intramural course (if present), and coronary outlets coupled to lumped parameter networks that included the dynamic microvascular compression. Each model was customized to the patients’ computed tomography angiography, vitals, and cardiac output. Results: All 6 AAORCAs had an interarterial course, and all but one had an intramural course. Measured iFRs ranged from 0.98 to 0.95 at rest, and from 0.95 to 0.80 with dobutamine-stress. The FSI model yielded realistic pressures and flows waveforms (Fig. 1). After we tuned the resistances to achieve flow rates at stress to be triple those at rest, the FSI simulations adequately matched the measured iFR (r = 0.85, RMSE = 0.04). Conclusions: Patient-specific FSI modeling is a promising non-invasive tool to assess the hemodynamic effects of AAORCA including the intramural course. However, the iFR’s sensitivity to the flow rate suggests a future role for quantitative stress-perfusion imaging to augment the iFR measurements for AAOCA risk stratification.

Aims Angina and no obstructive coronary artery disease (ANOCA) is common. A potential cause of angina in this patient population is a myocardial bridge (MB). We aimed to study the anatomical and haemodynamic characteristics of an MB in patients with ANOCA. Methods and results Using intravascular ultrasound (IVUS), we identified 184 MBs in 154 patients. We evaluated MB length, arterial compression, and halo thickness. MB muscle index (MMI) was defined as MB length×halo thickness. Haemodynamic testing of the MB was performed using an intracoronary pressure/Doppler flow wire at rest and during dobutamine stress. We defined an abnormal diastolic fractional flow reserve (dFFR) as ≤0.76 during stress. The median MB length was 22.9 mm, arterial compression 30.9%, and halo thickness 0.5 mm. The median MMI was 12.1. Endothelial and microvascular dysfunction were present in 85.4% and 22.1%, respectively. At peak dobutamine stress, 94.2% of patients had a dFFR ≤0.76 within and/or distal to the MB. MMI was associated with an abnormal dFFR. Conclusions In select patients with ANOCA who have an MB by IVUS, the majority have evidence of a haemodynamically significant dFFR during dobutamine stress, suggesting the MB as being a cause of their angina. A comprehensive invasive assessment of such patients during coronary angiography provides important diagnostic information that can guide management.

A myocardial bridge is a segment of a coronary artery that travels into the myocardium instead of the normal epicardial course. Although it is general perception that myocardial bridges are normal variants, patients with myocardial bridges can present with symptoms, such as exertional chest pain, that cannot be explained by a secondary etiology. Such patients may benefit from individualized medical/surgical therapy. This article describes the prevalence, clinical presentation, classification, evaluation, and management of children and adults with symptomatic myocardial bridges.

Background Myocardial bridges (MB) are commonly seen on coronary CT angiography (CCTA) in asymptomatic individuals, but in patients with recurrent typical angina symptoms, yet no obstructive coronary artery disease (CAD), evaluation of their potential hemodynamic significance is clinically relevant. The aim of this study was to compare CCTA to invasive coronary angiography (ICA), including intravascular ultrasound (IVUS), to confirm MB morphology and estimate their functional significance in symptomatic patients.Methods and Results:We retrospectively identified 59 patients from our clinical databases between 2009 and 2014 in whom the suspicion for MB was raised by symptoms of recurrent typical angina in the absence of significant obstructive CAD on ICA. All patients underwent CCTA, ICA and IVUS. MB length and depth by CCTA agreed well with length (0.6±23.7 mm) and depth (CT coverage) as seen on IVUS. The product of CT length and depth (CT coverage), (MB muscle index (MMI)), ≥31 predicted an abnormal diastolic fractional flow reserve (dFFR) ≤0.76 with a sensitivity and specificity of 74% and 62% respectively (area under the curve=0.722). Conclusions In patients with recurrent symptoms of typical angina yet no obstructive CAD, clinicians should consider dynamic ischemia from an MB in the differential diagnosis. The product of length and depth (i.e., MMI) by CCTA may provide some non-invasive insight into the hemodynamic significance of a myocardial bridge, as compared with invasive assessment with dFFR.

Background Myocardial bridge (MB) may cause angina in patients with no obstructive coronary artery disease (CAD). We previously reported a novel stress echocardiography (SE) pattern of focal septal buckling with apical sparing in the end-systolic to early-diastolic phase that is associated with the presence of an MB. We evaluated the diagnostic accuracy of this pattern, and prospectively validated our results. Methods The retrospective cohort included 158 patients with angina who underwent both SE and coronary CT angiography (CCTA). The validation cohort included 37 patients who underwent CCTA in the emergency department for angina, and prospectively underwent SE. CCTA was used as a reference standard for the presence/absence of an MB, and also confirmed no obstructive CAD. Results In the retrospective cohort, an MB was present in 107 (67.7%). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 91.6%, 70.6%, 86.7% and 80%, respectively. On logistic regression, focal septal buckling and Duke treadmill score were associated with an MB. In the validation cohort, an MB was present in 31 (84%). The sensitivity, specificity PPV and NPV were 90.3%, 83.3%, 96.5% and 62.5%, respectively. On logistic regression, focal septal buckling was associated with an MB. Conclusion Presence of focal septal buckling with apical sparing on SE is an accurate predictor of an MB in patients with angina and no obstructive CAD. This pattern can reliably be used to screen patients who may benefit from advanced non-invasive/invasive testing for an MB as a cause of their angina.

Background Arrhythmias are a leading cause of death in adults with congenital heart disease (ACHD). While 24-48-hour monitors are often used to assess arrhythmia burden, extended continuous ambulatory rhythm monitors (ECAM) can record 2 weeks of data. The utility of this device and the arrhythmia burden identified beyond 48-hour monitoring have not been evaluated in the ACHD population. Additionally, the impact of ECAM has not been studied to determine management recommendations. Objective To address the preliminary question, we hypothesized that clinically significant arrhythmias would be detected on ECAM beyond 48 hours and this would lead to clinical management changes. Methods A single center retrospective cohort study of ACHD patients undergoing ECAM from June 2013 to May 2016 was performed. The number and type of arrhythmias detected within and beyond the first 48 hours of monitoring were compared using Kaplan-Meier curves and Cox proportional hazard models. Results Three hundred fourteen patients had monitors performed [median age 31 (IQR 25-41) years, 61% female). Significant arrhythmias were identified in 156 patients (50%), of which 46% were noted within 48 hours. A management change based on an arrhythmia was made in 49 patients (16%). Conclusions ECAM detects more clinically significant arrhythmias than standard 48-hour monitoring in ACHD patients. Management changes, including medication changes, further testing or imaging, and procedures, were made based on results of ECAM. Recommendations and guidelines have been made based on arrhythmias on 48-hour monitoring; the predictive ability and clinical consequence of arrhythmias found on ECAM are not yet known.

See Article by Garcia-Ropero et al Since the 1970s, the Fontan operation has been used to palliate a heterogeneous group of patients with single-ventricle physiology. With improvements in surgical technique and medical care, large numbers of women are now surviving to child-bearing years, and many desire pregnancy.1 Preconception counseling and management of pregnancy in women status post–Fontan palliation was initially uncharted territory. Recommendations were based primarily on expert opinion. Unfortunately, because of the diverse anatomic variation in women with congenital heart disease and variations in underlying risk factors, research in this highly complex patient population is not straightforward. In this issue of Circulation: Cardiovascular Quality and Outcomes , Garcia-Ropero et al2 aim to conduct a systematic review of the literature published about pregnancy in women with prior Fontan surgery. Unfortunately, there are only 6 studies (2 from the same center with overlapping patient populations) describing outcomes during a 30-year time span. Acknowledging these limitations, the authors summarize information from 255 pregnancies in 133 women status post–Fontan palliation, which resulted in 115 live births. There were no maternal deaths reported, but complications included supraventricular arrhythmias, heart failure, premature delivery and small-for-gestational-age infants, and postpartum hemorrhage. This important article highlights the maternal and fetal risks of pregnancy in this unique patient population. However, the challenges in grouping the risks among a highly divergent, heterogeneous patient population with complex congenital heart disease are also apparent. The Fontan palliation is used to palliate a variety of conditions characterized by only a single well-developed ventricle. Lesions palliated by this procedure include tricuspid atresia, pulmonary atresia with intact ventricular septum, hypoplastic left heart syndrome, double inlet left ventricle, unbalanced atrioventricular canal …

Objective While >20% of patients presenting to the cardiac catheterization laboratory with angina have no obstructive coronary artery disease (CAD), a majority (77%) have an occult coronary abnormality (endothelial dysfunction, microvascular dysfunction (MVD), and/or a myocardial bridge (MB)). There are little data regarding the ability of noninvasive stress testing to identify these occult abnormalities in patients with angina in the absence of obstructive CAD. Methods We retrospectively evaluated 155 patients (76.7% women) with angina and no obstructive CAD who underwent stress echocardiography and/or electrocardiography before angiography. We evaluated Duke treadmill score, heart rate recovery (HRR), metabolic equivalents, and blood pressure response. During angiography, patients underwent invasive testing for endothelial dysfunction (decrease in epicardial coronary artery diameter >20% after intracoronary acetylcholine), MVD (index of microcirculatory resistance ≥25), and intravascular ultrasound for the presence of an MB. Results Stress echocardiography and electrocardiography were positive in 58 (43.6%) and 57 (36.7%) patients, respectively. Endothelial dysfunction was present in 96 (64%), MVD in 32 (20.6%), and an MB in 83 (53.9%). On multivariable logistic regression, stress echo was not associated with any abnormality, while stress ECG was associated with endothelial dysfunction. An abnormal HRR was associated with endothelial dysfunction and MVD, but not an MB. Conclusion Conventional stress testing is insufficient for identifying occult coronary abnormalities that are frequently present in patients with angina in the absence of obstructive CAD. A normal stress test does not rule out a non-obstructive coronary etiology of angina, nor does it negate the need for comprehensive invasive testing.

Obtaining focused right ventricular (RV) apical view remains challenging using conventional two-dimensional (2D) echocardiography. This study main objective was to determine whether measurements from RV focused views derived from three-dimensional (3D) echocardiography (3D-RV-focused) are closely related to measurements from magnetic resonance (CMR). A first cohort of 47 patients underwent 3D echocardiography and CMR imaging within 2 h of each other. A second cohort of 25 patients had repeat 3D echocardiography to determine the test–retest characteristics; and evaluate the bias associated with unfocused RV views. Tomographic views were extracted from the 3D dataset: RV focused views were obtained using the maximal RV diameter in the transverse plane, and unfocused views from a smaller transverse diameter enabling visualization of the tricuspid valve opening. Measures derived using the 3D-RV-focused view were strongly associated with CMR measurements. Among functional metrics, the strongest association was between RV fractional area change (RVFAC) and ejection fraction (RVEF) (r = 0.92) while tricuspid annular plane systolic excursion moderately correlated with RVEF (r = 0.47), all p

Background A myocardial bridge (MB) has been associated with ventricular arrhythmia and sudden death during exercise. QT dispersion (QTd) is a measure of abnormal repolarization and may predict ventricular arrhythmia. We investigated the frequency of ventricular arrhythmias during exercise and the QTd at rest and after exercise, in patients with an MB compared to a normal cohort. Methods We studied the rest and stress ECG tracings of patients with an MB suspected by focal septal buckling on exercise echocardiography (EE) (Echo-MB group, N = 510), those with an MB confirmed by another examination (MB group, N = 110), and healthy controls (Control group, N = 198). Results The frequency of exercise-induced premature ventricular contractions (PVCs) was significantly higher in the Echo-MB and MB groups compared with the Control group (both p

Background Although myocardial bridges (MBs) are traditionally regarded as incidental findings, it has been reported that adult patients with symptomatic MBs refractory to medical therapy benefit from unroofing. However, there is limited literature in the pediatric population. The aim of our study was to evaluate the indications and outcomes for unroofing in pediatric patients. Methods We retrospectively reviewed all pediatric patients with MB in our institution who underwent surgical relief. Clinical characteristics, relevant diagnostic data, intraoperative findings, and postoperative outcomes were evaluated. Results Between 2012 and 2016, 14 pediatric patients underwent surgical unroofing of left anterior descending artery MBs. Thirteen patients had anginal symptoms refractory to medical therapy, and 1 patient was asymptomatic until experiencing aborted sudden cardiac arrest during exercise. Thirteen patients underwent exercise stress echocardiography, all of which showed mid-septal dys-synergy. Coronary computed tomography imaging confirmed the presence of MBs in all patients. Intravascular ultrasound imaging confirmed the length of MBs: 28.2 ± 16.3 mm, halo thickness: 0.59 ± 0.24 mm, and compression of left anterior descending artery at resting heart rate: 33.0 ± 11.6%. Invasive hemodynamic assessment with dobutamine confirmed the physiologic significance of the MBs with diastolic fractional flow reserve: 0.59 ± 0.13. Unroofing was performed with the patient under cardiopulmonary bypass (CPB) in the initial 9 cases and without CPB in the subsequent 5 cases. All patients were discharged without complications. The 13 symptomatic patients reported resolution of symptoms on follow-up, and improvement in symptoms and quality of life was documented using the Seattle Angina Questionnaire version 7. Conclusions Unroofing of MBs can be safely performed in pediatric patients, with or without use of CPB. In symptomatic patients, unroofing can provide relief of symptoms refractory to medical therapy.

Background— Coronary computed tomographic angiography (cCTA) allows rapid, noninvasive exclusion of obstructive coronary artery disease (CAD). However, concern exists whether implementation of cCTA in the assessment of patients presenting to the emergency department with acute chest pain will lead to increased downstream testing and costs compared with alternative strategies. Our aim was to compare observed actual costs of usual care (UC) with projected costs of a strategy including early cCTA in the evaluation of patients with acute chest pain in the Rule Out Myocardial Infarction Using Computer Assisted Tomography I (ROMICAT I) study. Methods and Results— We compared cost and hospital length of stay of UC observed among 368 patients enrolled in the ROMICAT I study with projected costs of management based on cCTA. Costs of UC were determined by an electronic cost accounting system. Notably, UC was not influenced by cCTA results because patients and caregivers were blinded to the cCTA results. Costs after early implementation of cCTA were estimated assuming changes in management based on cCTA findings of the presence and severity of CAD. Sensitivity analysis was used to test the influence of key variables on both outcomes and costs. We determined that in comparison with UC, cCTA-guided triage, whereby patients with no CAD are discharged, could reduce total hospital costs by 23% ( P 28% to 33%, the use of cCTA becomes more costly than UC. Conclusions— cCTA may be a cost-saving tool in acute chest pain populations that have a prevalence of potentially obstructive CAD Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00990262.

Background— 9p21.3 is among the most strongly replicated regions for cardiovascular disease. There are few reports of sequencing the associated 9p21.3 interval. We set out to sequence the 9p21.3 region followed by a comprehensive study of genetic associations with clinical and subclinical cardiovascular disease and its risk factors, as well as with copy number variation and gene expression, in the Framingham Heart Study (FHS). Methods and Results— We sequenced 281 individuals (94 with myocardial infarction, 94 with high coronary artery calcium levels, and 93 control subjects free of elevated coronary artery calcium or myocardial infarction), followed by genotyping and association in >7000 additional FHS individuals. We assessed genetic associations with clinical and subclinical cardiovascular disease, risk factor phenotypes, and gene expression levels of the protein-coding genes CDKN2A and CDKN2B and the noncoding gene ANRIL in freshly harvested leukocytes and platelets. Within this large sample, we found strong associations of 9p21.3 variants with increased risk for myocardial infarction, higher coronary artery calcium levels, and larger abdominal aorta diameters and no evidence for association with traditional cardiovascular disease risk factors. No common protein-coding variation, variants in splice donor or acceptor sites, or copy number variation events were observed. By contrast, strong associations were observed between genetic variants and gene expression, particularly for a short isoform of ANRIL and for CDKN2B . Conclusions— Our thorough genomic characterization of 9p21.3 suggests common variants likely account for observed disease associations and provides further support for the hypothesis that complex regulatory variation affecting ANRIL and CDKN2B gene expression may contribute to increased risk for clinically apparent and subclinical coronary artery disease and aortic disease.

The adult with congenital heart disease (CHD) is at risk of developing atherosclerotic cardiovascular disease (ASCVD). We performed a cross-sectional study to describe established ASCVD risk factors and estimate 10-year and lifetime risk of ASCVD in adults over age 18 with CHD of moderate or great complexity using three validated risk assessment tools—the Framingham Study Cardiovascular Disease Risk Assessment, the Reynolds Risk Score, and the Atherosclerotic Cardiovascular Disease (ASCVD) Risk Estimator. We obtained extensive clinical and survey data on 178 enrolled patients, with average age 37.1±12.6 years, 51% men. At least one modifiable ASCVD risk factor was present in 70%; the two most common were overweight/obesity (53%) and systemic hypertension (24%). Laboratory data was available in 103 of the 178 patients. Abnormal levels of glycated hemoglobin, high-sensitivity C-reactive protein, and high-density lipoprotein (HDL) were each found in around 30% of patients. The 10-year ASCVD predicted risk using all three tools was relatively low (i.e., at least 90% of patients

Left anterior descending artery myocardial bridges (MBs) range from clinically insignificant incidental angiographic findings to a potential cause of sudden cardiac death. Within this spectrum, a group of patients with isolated, symptomatic, and hemodynamically significant MBs despite maximally tolerated medical therapy exist for whom the optimal treatment is controversial. We evaluated supraarterial myotomy, or surgical unroofing, of the left anterior descending MBs as an isolated procedure in these patients.In 50 adult patients, we prospectively evaluated baseline clinical characteristics, risk factors, and medications for coronary artery disease, relevant diagnostic data (stress echocardiography, computed tomography angiography, stress coronary angiogram with dobutamine challenge for measurement of diastolic fractional flow reserve, and intravascular ultrasonography), and anginal symptoms using the Seattle Angina Questionnaire. These patients then underwent surgical unroofing of their left anterior descending artery MBs followed by readministration of the Seattle Angina Questionnaire at 6.6-month (range, 2 to 13) follow-up after surgery.Dramatic improvements were noted in physical limitation due to angina (52.0 versus 87.1, p0.001), anginal stability (29.6 versus 66.4, p0.001), anginal frequency (52.1 versus 84.7, p0.001), treatment satisfaction (76.1 versus 93.9, p0.001), and quality of life (25.0 versus 78.9, p0.001), all five dimensions of the Seattle Angina Questionnaire. There were no major complications or deaths.Surgical unroofing of carefully selected patients with MBs can be performed safely as an independent procedure with significant improvement in symptoms postoperatively. It is the optimal treatment for isolated, symptomatic, and hemodynamically significant MBs resistant to maximally tolerated medical therapy.

Objectives: Anomalous aortic origin of a coronary artery (AAOCA) has been associated with myocardial ischemia and sudden death. The past decade has provided important insights into the natural history and typical patterns of presentation. However, there are also a number of unresolved controversies regarding the indications for surgery and the efficacy of that surgery. The purpose of this study was to review our surgical experience with AAOCA in 115 patients at a single institution. Design: One hundred and fifteen patients have undergone surgical repair of AAOCA at our institution. There were 82 males and 33 females, and the median age at surgery was 16 years. Fifty-nine patients had preoperative symptoms of myocardial ischemia, including 56 with exertional chest pain or syncope and 3 sudden death events. Twenty-four patients had associated congenital heart defects. Seven patients had an associated myocardial bridge. Results: Surgical repair was accomplished by unroofing of an intramural coronary in 86, reimplantation in 9, and pulmonary artery translocation in 20. There has been no early or late mortality. Fifty-seven (97%) of the 59 symptomatic patients have been free of any cardiac symptoms postoperatively. Two patients had recurrent symptoms and underwent reoperation (one had revision of the initial repair and one had repair of a myocardial bridge). Conclusions: Surgical repair of AAOCA can be safely performed and is highly efficacious in relieving symptoms of myocardial ischemia. The two “surgical failures” in this series had an anatomic basis and underscore the need to reassess both the proximal and distal anatomy in these patients.

Early triage of patients presenting to the emergency department (ED) with the chief complaint of chest pain suggestive of acute coronary syndrome (ACS) remains a diagnostic challenge. Elements of the chest pain history are associated with increased or decreased likelihoods of ACS.1 Sensitive troponin assays and initial electrocardiogram (ECG) provide important information in the initial decision.2–4 However, clinical history, a single set of cardiac biomarkers, and the initial ECG alone or in combination cannot identify the group of patients who can be safely discharged without further diagnostic testing. The percentage of patients who present to the ED with ACS and are inappropriately discharged is low (around 2%).5 However, discharged subjects have a two to three times increased risk of dying.5 Therefore, the standard of care for subjects with acute chest pain typically includes serial ECG and cardiac biomarkers followed by a stress test with or without imaging.6–9 The standard work-up decreases the risk of diagnostic errors. However, the complete “rule-out myocardial infarction” protocol is time-consuming and costly. Clinical risk scores (e.g., Thrombolysis in Myocardial Infarction [TIMI],10 Goldman,11 and Sanchis12) and triage algorithms are available to predict adverse cardiac events and facilitate the triage decision.10–14 However, the performance of these tools is not optimal.15 Risk scores used for the prediction of future cardiovascular events (e.g., Framingham Risk Score) and risk factors for coronary artery disease (CAD) have only limited value for the confirmation or exclusion of ACS in the ED.16,17 Coronary computed tomography angiography (CTA) permits detection of coronary stenosis and atherosclerotic plaque with high sensitivity, specificity, and negative predictive value.18–22 In patients who present to the ED with acute chest pain, exclusion of a significant coronary stenosis and plaque by coronary CTA has a high negative predictive value for ACS.23–32 In contrast, patients with a significant coronary stenosis detected by computed tomography (CT) have a high likelihood of ACS. However, there is a significant proportion of patients in whom coronary atherosclerotic plaque is present, without significant stenosis. In the Rule Out Myocardial Infarction Using Computer-Assisted Tomography (ROMICAT) trial, we observed approximately one-third (113 of 368) of patients with nonobstructive plaque.28 The quantitative assessment of coronary plaque and the combination of coronary plaque burden with clinical risk scores could possibly improve the accuracy for the diagnosis as well as the exclusion of ACS. We determined the association of four dichotomized (low- vs. intermediate- to high-risk categories) clinical risk scores and of the coronary atherosclerotic plaque burden as detected by CT with the outcome of ACS in patients who presented to the ED with the chief complaint of chest pain and inconclusive initial evaluation (negative cardiac biomarkers, nondiagnostic ECG changes), and no history of CAD. We hypothesized that the combination of risk scores and plaque burden improves the discriminatory capacity for the diagnosis of ACS.

We tested the hypothesis that morphologic lesion assessment helps detect acute coronary syndrome (ACS) during index hospitalization in patients with acute chest pain and significant stenosis on coronary computed tomographic angiogram (CTA). Patients who presented to an emergency department with chest pain but no objective signs of myocardial ischemia (nondiagnostic electrocardiogram and negative initial biomarkers) underwent CT angiography. CTA was analyzed for degree and length of stenosis, plaque area and volume, remodeling index, CT attenuation of plaque, and spotty calcium in all patients with significant stenosis (>50% in diameter) on CTA. ACS during index hospitalization was determined by a panel of 2 physicians blinded to results of CT angiography. For lesion characteristics associated with ACS, we determined cutpoints optimized for diagnostic accuracy and created lesion scores. For each score, we determined the odds ratio (OR) and discriminatory capacity for the prediction of ACS. Of the overall population of 368 patients, 34 had significant stenosis and 21 of those had ACS. Scores A (remodeling index plus spotty calcium: OR 3.5, 95% confidence interval [CI] 1.2 to 10.1, area under curve [AUC] 0.734), B (remodeling index plus spotty calcium plus stenosis length: OR 4.6, 95% CI 1.6 to 13.7, AUC 0.824), and C (remodeling index plus spotty calcium plus stenosis length plus plaque volume

Background Myocardial stress computed tomography perfusion (CTP) has similar diagnostic accuracy for detecting perfusion defects (PDs) versus single-photon emission computed tomography (SPECT). However, the optimal diagnostic viewing and image processing parameters for CTP are unknown. Objective We sought to compare the diagnostic accuracy of different image processing techniques, cardiac phases, slice thicknesses, and viewing parameters for detection of PDs. Methods A stress and rest dual-source CTP protocol was performed with adenosine. Twelve subjects with severe stenosis proven by quantitative coronary angiography (QCA), with corresponding territorial defects at SPECT, were selected as well as 7 controls (subjects with similar clinical suspicion but negative QCA and SPECT). Short-axis stress images were processed with 3 techniques: minimum intensity projection (MinIP), maximum intensity projection, and average intensity multiplanar reconstruction (MPR), 3 thicknesses (1, 3, 8 mm), and 2 phases (systolic, mid-diastolic). The resulting images (n = 1026) were randomized and interpreted by independent readers. Results Diastolic reconstructions (8-mm MPR) showed the highest sensitivity (81%) to detect true PDs. The highest accuracy was achieved with the 8-mm (61%) and 1-mm (61%) MPR diastolic images. The most sensitive and accurate systolic reconstructions were 3-mm MinIP images. These findings related to viewing in relatively narrow window width and window level settings. Conclusion Viewing parameters for optimal accuracy in detection of perfusion defects on CTP differ for systolic and diastolic images.

Newer cardiac computed tomographic (CT) technology has permitted comprehensive cardiothoracic evaluations for coronary artery disease, pulmonary embolism, and aortic dissection within a single breath hold, independent of the heart rate. We conducted a randomized diagnostic trial to compare the efficiency of a comprehensive cardiothoracic CT examination in the evaluation of patients presenting to the emergency department with undifferentiated acute chest discomfort or dyspnea. We randomized the emergency department patients clinically scheduled to undergo a dedicated CT protocol to assess coronary artery disease, pulmonary embolism, or aortic dissection to either the planned dedicated CT protocol or a comprehensive cardiothoracic CT protocol. All CT examinations were performed using a 64-slice dual source CT scanner. The CT results were immediately communicated to the emergency department providers, who directed further management at their discretion. The subjects were then followed for the remainder of their hospitalization and for 30 days after hospitalization. Overall, 59 patients (mean age 51.2 ± 11.4 years, 72.9% men) were randomized to either dedicated (n = 30) or comprehensive (n = 29) CT scanning. No significant difference was found in the median length of stay (7.6 vs 8.2 hours, p = 0.79), rate of hospital discharge without additional imaging (70% vs 69%, p = 0.99), median interval to exclusion of an acute event (5.2 vs 6.5 hours, p = 0.64), costs of care (p = 0.16), or the number of revisits (p = 0.13) between the dedicated and comprehensive arms, respectively. In addition, radiation exposure (11.3 mSv vs 12.8 mSv, p = 0.16) and the frequency of incidental findings requiring follow-up (24.1% vs 33.3%, p = 0.57) were similar between the 2 arms. Comprehensive cardiothoracic CT scanning was feasible, with a similar diagnostic yield to dedicated protocols. However, it did not reduce the length of stay, rate of subsequent testing, or costs. In conclusion, although this "triple rule out" protocol might be helpful in the evaluation of select patients, these findings suggest that it should not be used routinely with the expectation that it will improve efficiency or reduce resource use.

Background— The incremental value of regional left ventricular function (LVF) over coronary assessment to detect acute coronary syndrome (ACS) is uncertain. Methods and Results— We analyzed 356 patients (mean age, 53±12 years; 62% men) with acute chest pain and inconclusive initial emergency department evaluation. Patients underwent 64-slice contrast-enhanced cardiac computed tomography before hospital admission. Caregivers and patients remained blinded to the results. Regional LVF and presence of coronary atherosclerotic plaque and significant stenosis (>50%) were separately assessed by 2 independent readers. Incremental value of regional LVF to predict ACS was determined in the entire cohort and in subgroups of patients with nonobstructive coronary artery disease, inconclusive assessment for stenosis (defined as inability to exclude significant stenosis due to calcium or motion), and significant stenosis. During their index hospitalization, 31 patients were ultimately diagnosed with ACS (8 myocardial infarction, 22 unstable angina), of which 74% (23 patients) had regional LV dysfunction. Adding regional LVF resulted in a 10% increase in sensitivity to detect ACS by cardiac computed tomography (87%; 95% confidence interval, 70% to 96%) and significantly improved the overall accuracy (c-statistic: 0.88 versus 0.94 and 0.79 versus 0.88, for extent of plaque and presence of stenosis, respectively; both P Conclusions— Regional LVF assessment at rest improves diagnostic accuracy for ACS in patients with acute chest pain, especially in those with coronary artery disease and thus may be helpful to guide further management in patients at intermediate risk for ACS. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00990262.

We aimed to determine predictors of image quality in consecutive patients who underwent coronary computed tomography (CT) for the evaluation of acute chest pain.We prospectively enrolled patients who presented with chest pain to the emergency department. All subjects underwent contrast-enhanced 64-slice coronary multi-detector CT. Two experienced readers determined overall image quality on a per-patient basis and the prevalence and characteristics of non-evaluable coronary segments on a per-segment basis.Among 378 subjects (143 women, age: 52.9+/-11.8 years), 345 (91%) had acceptable overall image quality, while 33 (9%) had poor image quality or were unreadable. In adjusted analysis, patients with diabetes, hypertension and a higher heart rate during the scan were more likely to have exams graded as poor or unreadable (odds ratio [OR]: 2.94, p=0.02; OR: 2.62, p=0.03; OR: 1.43, p=0.02; respectively). Of 6253 coronary segments, 257 (4%) were non-evaluable, most due to severe calcification in combination with motion (35%). The presence of non-evaluable coronary segments was associated with age (OR: 1.08 annually, 95%-confidence interval [CI]: 1.05-1.12, p0.001), baseline heart rate (OR: 1.35 per 10 beats/min, 95%-CI: 1.11-1.67, p=0.003), diabetes, hypertension, and history of coronary artery disease (OR: 4.43, 95%-CI: 1.93-10.17, p0.001; OR: 2.27, 95-CI: 1.01-4.73, p=0.03; OR: 5.12, 95%-CI: 2.0-13.06, p0.001; respectively).Coronary CT permits acceptable image quality in more than 90% of patients with chest pain. Patients with multiple risk factors are more likely to have impaired image quality or non-evaluable coronary segments. These patients may require careful patient preparation and optimization of CT scanning protocols.

Objectives This study tested the hypothesis that fluorodeoxyglucose (FDG) uptake within the ascending aorta and left main coronary artery (LM), measured using positron emission tomography (PET), is greater in patients with recent acute coronary syndrome (ACS) than in patients with stable angina. Background Inflammation is known to play an important role in atherosclerosis. Positron emission tomography imaging with 18F-FDG provides a measure of plaque inflammation. Methods Twenty-five patients (mean age 57.9 ± 9.8 years, 72% male, 10 ACS, and 15 stable angina) underwent cardiac computed tomographic angiography and PET imaging with 18F-FDG after invasive angiography. Images were coregistered, and FDG uptake was measured at locations of interest for calculation of target-to-background ratios (TBR). Additionally, FDG uptake was measured at the site of the lesion deemed clinically responsible for the presenting syndrome (culprit) by virtue of locating the stent deployed to treat the syndrome. Results The FDG uptake was higher in the ACS versus the stable angina groups in the ascending aorta (median [interquartile ranges] TBR 3.30 [2.69 to 4.12] vs. 2.43 [2.00 to 2.86], p = 0.02), as well as the LM (2.48 [2.30 to 2.93] vs. 2.00 [1.71 to 2.44], p = 0.03, respectively). The TBR was greater for culprit lesions associated with ACS than for lesions stented for stable coronary syndromes (2.61 vs. 1.74, p = 0.02). Furthermore, the TBR in the stented lesions (in ACS and stable angina groups) correlated with C-reactive protein (r = 0.58, p = 0.04). Conclusions This study shows that in patients with recent ACS, FDG accumulation is increased both within the culprit lesion as well as in the ascending aorta and LM. This observation suggests inflammatory activity within atherosclerotic plaques in acute coronary syndromes and supports intensification of efforts to refine PET methods for molecular imaging of coronary plaques.

Myocardial bridge (MB) muscle index (MMI), the product of MB depth x length, is suggestive of severity of an MB. MBs are also associated with endothelial dysfunction. We studied the relationship of MMI with endothelial function, and its effect on symptomatic outcome in patients undergoing surgical

First, to assess the feasibility of a protocol involving stress-induced perfusion evaluated at computed tomography (CT) combined with cardiac CT angiography in a single examination and second, to assess the incremental value of perfusion imaging over cardiac CT angiography in a dual-source technique for the detection of obstructive coronary artery disease (CAD) in a high-risk population.Institutional review board approval and informed patient consent were obtained before patient enrollment in the study. The study was HIPAA compliant. Thirty-five patients at high risk for CAD were prospectively enrolled for evaluation of the feasibility of CT perfusion imaging. All patients underwent retrospectively electrocardiographically gated (helical) adenosine stress CT perfusion imaging followed by prospectively electrocardiographically gated (axial) rest myocardial CT perfusion imaging. Analysis was performed in three steps: (a)Coronary arterial stenoses were scored for severity and reader confidence at cardiac CT angiography, (b)myocardial perfusion defects were identified and scored for severity and reversibility at CT perfusion imaging, and (c)coronary stenosis severity was reclassified according to perfusion findings at combined cardiac CT angiography and CT perfusion imaging. The sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of cardiac CT angiography before and after CT perfusion analysis were calculated.With use of a reference standard of greater than 50% stenosis at invasive angiography, all parameters of diagnostic accuracy increased after CT perfusion analysis: Sensitivity increased from 83% to 91%; specificity, from 71% to 91%; PPV, from 66% to 86%; and NPV, from 87% to 93%. The area under the receiver operating characteristic curve increased significantly, from 0.77 to 0.90 (P.005).A combination protocol involving adenosine perfusion CT imaging and cardiac CT angiography in a dual-source technique is feasible, and CT perfusion adds incremental value to cardiac CT angiography in the detection of significant CAD.

We have recently described a technique for assessing myocardial perfusion using adenosine-mediated stress imaging (CTP) with dual source computed tomography. SPECT myocardial perfusion imaging (SPECT-MPI) is a widely utilized and extensively validated method for assessing myocardial perfusion. The aim of this study was to determine the level of agreement between CTP and SPECT-MPI at rest and under stress on a per-segment, per-vessel, and per-patient basis. Forty-seven consecutive patients underwent CTP and SPECT-MPI. Perfusion images were interpreted using the 17 segment AHA model and were scored on a 0 (normal) to 3 (abnormal) scale. Summed rest and stress scores were calculated for each vascular territory and patient by adding corresponding segmental scores. On a per-segment basis (n = 799), CTP and SPECT-MPI demonstrated excellent correlation: Goodman-Kruskall γ = .59 (P

Background Aortic valve calcification (AVC) is associated with cardiovascular risk factors and coronary artery calcification. We sought to determine whether AVC is associated with the presence and extent of overall plaque burden, as well as to plaque composition (calcified, mixed, and noncalcified). Methods We examined 357 subjects (mean age 53 ± 12 years, 61% male) who underwent contrast-enhanced electrocardiogram-gated 64-slice multidetector computed tomography from the ROMICAT trial for the assessment of presence and extent of coronary plaque burden according to the 17-coronary segment model and presence of AVC. Results Patients with AVC (n = 37, 10%) were more likely than those without AVC (n = 320, 90%) to have coexisting presence of any coronary plaque (89% vs 46%, P P 3-fold increase odds of having any plaque (adjusted odds ratio [OR] 3.6, P = .047) and an increase of 2.5 segments of plaque ( P P = .004), then mixed plaque (OR 3.2, P = .02), but not with noncalcified plaque ( P = .96). Conclusion Aortic valve calcification is associated with the presence and greater extent of coronary artery plaque burden and may be part of the later stages of the atherosclerosis process, as its relation is strongest with calcified plaque, less with mixed plaque, and nonsignificant with noncalcified plaque. If AVC is present, consideration for aggressive medical therapy may be warranted.

Objective The aim of the study was to assess differences in the presence, extent, and composition of coronary atherosclerotic plaque burden as detected by coronary multidetector computed tomography (MDCT) between patients with and without diabetes mellitus. Methods We compared coronary atherosclerotic plaques (any plaque, calcified [CAP], non-calcified [NCAP, and mixed plaque [MCAP]]) between 144 symptomatic diabetic and non-diabetic patients (36 diabetics, mean age: 54.4+/-12, 64% females) who underwent coronary 64-slice MDCT (Siemens Medical Solutions, Forchheim, Germany) for the evaluation of acute chest pain but proven absence of myocardial ischemia. Results Patients with diabetes had a higher prevalence of any plaque, CAP, MCAP, and NCAP (p=0.08, 0.07, 0.05, and 0.05, respectively) and a significantly higher extent of any plaque, CAP, MCAP, and NCAP (3.8+/-4.2 vs. 2.0+/-3.2, p=0.01; 3.3+/-4.0 vs. 1.7+/-3.0, p=0.03; 1.4+/-2.6 vs. 0.6+/-1.5, p=0.03; and 1.9+/-3.0 vs. 1.0+/-1.9, p=0.03, respectively) as compared to controls. In addition, patients with diabetes had a significant higher prevalence of significant coronary artery stenosis (42% vs. 14%, p=0.0004) and an approximately 3.5-fold higher risk of significant coronary stenosis independent of the presence of hypertension and BMI (OR: 3.46, 95% CI: 1.37-8.74, p=0.009). Conclusion Patients with diabetes have an approximately 3.5-fold higher risk of coronary stenosis independent of other cardiovascular risk factors and an overall increased coronary atherosclerotic plaque burden.

Objectives This study was designed to determine the usefulness of coronary computed tomography angiography (CTA) in patients with acute chest pain. Background Triage of chest pain patients in the emergency department remains challenging. Methods We used an observational cohort study in chest pain patients with normal initial troponin and nonischemic electrocardiogram. A 64-slice coronary CTA was performed before admission to detect coronary plaque and stenosis (>50% luminal narrowing). Results were not disclosed. End points were acute coronary syndrome (ACS) during index hospitalization and major adverse cardiac events during 6-month follow-up. Results Among 368 patients (mean age 53 ± 12 years, 61% men), 31 had ACS (8%). By coronary CTA, 50% of these patients were free of coronary artery disease (CAD), 31% had nonobstructive disease, and 19% had inconclusive or positive computed tomography for significant stenosis. Sensitivity and negative predictive value for ACS were 100% (n = 183 of 368; 95% confidence interval [CI]: 98% to 100%) and 100% (95% CI: 89% to 100%), respectively, with the absence of CAD and 77% (95% CI: 59% to 90%) and 98% (n = 300 of 368, 95% CI: 95% to 99%), respectively, with significant stenosis by coronary CTA. Specificity of presence of plaque and stenosis for ACS were 54% (95% CI: 49% to 60%) and 87% (95% CI: 83% to 90%), respectively. Only 1 ACS occurred in the absence of calcified plaque. Both the extent of coronary plaque and presence of stenosis predicted ACS independently and incrementally to Thrombolysis In Myocardial Infarction risk score (area under curve: 0.88, 0.82, vs. 0.63, respectively; all p Conclusions Fifty percent of patients with acute chest pain and low to intermediate likelihood of ACS were free of CAD by computed tomography and had no ACS. Given the large number of such patients, early coronary CTA may significantly improve patient management in the emergency department.

Background Although a myocardial bridge ( MB ) is often regarded as a benign coronary variant, recent studies have associated MB with focal myocardial ischemia. The physiological consequences of MB on ventricular function during stress have not been well established. Methods and Results We enrolled 58 patients with MB of the left anterior descending artery, diagnosed by intravascular ultrasound. Patients underwent invasive physiological evaluation of the MB by diastolic fractional flow reserve during dobutamine challenge and exercise echocardiography. Septal and lateral longitudinal strain (LS) were assessed at rest and immediately after exercise and compared with strain of matched controls. Absolute and relative changes in strain were also calculated. The mean age was 42.5±16.0 years. Fifty‐five patients had a diastolic fractional flow reserve ≤0.76. At rest, there was no significant difference between the 2 groups in septal LS (19.0±1.8% for patients with MB versus 19.2±1.5% for control, P =0.53) and lateral LS (20.1±2.0% versus 20.0±1.6%, P =0.83). With stress, compared with controls, patients with MB had a lower peak septal LS (18.9±2.6% versus 21.7±1.6%, P P P LS , whereas there was no significant difference in lateral LS . In multivariate analysis, diastolic fractional flow reserve and length were independent determinants of lower changes in septal LS. Conclusions Patients with a hemodynamically significant MB , determined by invasive diastolic fractional flow reserve , have significantly lower change in septal LS on exercise echocardiography, suggesting that septal LS may be useful for noninvasively assessing the hemodynamic significance of an MB .

Giant coronary aneurysms are rare. We present a 25-year-old woman with a known history of non-Kawasaki/nonatherosclerotic bilateral coronary aneurysms. She was transferred to our facility with acute coronary syndrome complicated by cardiogenic shock. Angiography demonstrated giant bilateral coronary aneurysms and complete occlusion of the left anterior descending (LAD) artery. Emergent coronary artery bypass grafting was performed. Coronary artery bypass grafting is the preferred approach for addressing giant coronary aneurysms. Intervention on the aneurysm varies in the literature. Aggressive revascularization is recommended in the non-Kawasaki/nonatherosclerotic aneurysm patient, and ligation should be performed in patients with thromboembolic phenomena.

Diagnosis and assessment of severity in patients with myocardial bridge (MB) currently depend on invasive measures. Left ventricular strain during stress echocardiography is a non-invasive method to evaluate left ventricular dysfunction. We identified MB of the LAD in 58 patients by intravascular

Peripartum coronary artery dissection is rare, but it is an increasingly recognized risk to women of childbearing age. Literature reviews reveal that about 80% of the population with spontaneous coronary artery dissections (SCAD) are female, and approximately 25–33% of cases occurred while the woman was pregnant or in the peripartum phase. Most cases have presented within 2 weeks of delivery. The left anterior descending is the most commonly affected vessel. The etiology is poorly understood, but many reports suggest that SCAD occurs as a result of protease release secondary to an eosinophilic vasculitis resulting in vessel lysis. Many investigators have examined the correlation between peripartum SCAD and estrogen levels; however, case studies have shown conflicting results regarding estrogen levels as the putative causative factor. Optimal treatment remains controversial. Presently, stenting appears to be best employed in the patients who have single‐vessel dissection not involving the left main coronary artery (LMCA). Surgical revascularization via coronary artery bypass graft remains the optimal therapy in patients whose dissection involves the LMCA, in patients with concurrent multi‐vessel dissection, and in patients with disease refractory to medical management. It is important to consider coronary artery dissection in the differential of any young woman who presents with signs or symptoms consistent with acute coronary syndrome, particularly if she is peripartum. Furthermore, once suspected, it is imperative that a definitive diagnostic study, that is, coronary angiography, be completed prior to the initiation of treatment whenever possible.

Background Patients with a myocardial bridge ( MB ) and no significant obstructive coronary artery disease ( CAD ) may experience angina presumably from ischemia, but noninvasive assessment has been limited and the underlying mechanism poorly understood. This study seeks to correlate a novel exercise echocardiography ( EE ) finding for MB s with invasive structural and hemodynamic measurements. Methods and Results Eighteen patients with angina and an EE pattern of focal end‐systolic to early‐diastolic buckling in the septum with apical sparing were prospectively enrolled for invasive assessment. This included coronary angiography, left anterior descending artery ( LAD ) intravascular ultrasound ( IVUS ), and intracoronary pressure and D oppler measurements at rest and during dobutamine stress. All patients were found to have an LAD MB on IVUS . The ratios of diastolic intracoronary pressure divided by aortic pressure at rest (Pd/Pa) and during dobutamine stress (diastolic fractional flow reserve [ dFFR ]) and peak D oppler flow velocity recordings at rest and with stress were successfully performed in 14 patients. All had abnormal dFFR (≤0.75) at stress within the bridge, distally or in both positions, and on average showed a more than doubling in peak D oppler flow velocity inside the MB at stress. Seventy‐five percent of patients had normalization of dFFR distal to the MB , with partial pressure recovery and a decrease in peak D oppler flow velocity. Conclusions A distinctive septal wall motion abnormality with apical sparing on EE is associated with a documented MB by IVUS and a decreased dFFR . We posit that the septal wall motion abnormality on EE is due to dynamic ischemia local to the compressed segment of the LAD from the increase in velocity and decrease in perfusion pressure, consistent with the V enturi effect.