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Background: Exercise electrocardiography (ECG) is frequently used as a diagnostic measure in patients with suspected coronary artery disease (CAD). However, it has low sensitivity for the detection of CAD. Magnetocardiography (MCG) has been proposed as an alternative tool to accurately diagnose CAD., Objective: To date, a direct comparison of MCG to ECG has not been performed. This study sought to compare them for predicting the presence of significantly obstructive CAD., Methods: The patients with chest pain or other symptoms suggestive of CAD were enrolled in the analysis. All the patients underwent a clinical evaluation, exercise ECG, MCG test, and coronary angiography (CA). CAD was defined as stenosis ≥70% in at least one major coronary artery on quantitative analysis of CA., Results: We prospectively enrolled 202 consecutive patients who suggested CAD. The prevalence of CAD on CA was 39.1%. Sensitivity and accuracy for CAD diagnosis was higher for MCG compared with exercise ECG (sensitivities 68.4% and 40.5%, p <0.001, specificities 95.1% and 91.1%, p = 0.267, and accuracies 84.7% and 71.3%, p <0.001, respectively). There was no incremental diagnostic value of combined MCG and ECG to detect coronary artery disease (p = 0.357)., Conclusions: For the patients with intermediate to high risk of CAD, MCG exercise test provides better diagnostic accuracy for the detection of relevant obstruction of the epicardial coronaries when directly compared to exercise ECG.

Background: Magnetocardiography (MCG) has been proposed as a non-invasive and functional technique with high accuracy for diagnosis of myocardial ischemia., Objective: This study sought to develop a novel scoring system of MCG for predicting the presence of significant obstructive coronary artery disease (CAD)., Methods: In a training set of 108 subjects, predictors of ≥70% stenosis in at least one major coronary vessel were prospectively identified from MCG variables. The final model was then retrospectively validated in a separate set of 45 subjects., Results: In the multivariable logistic regression, among those in the training set, elevated scores were predictive of ≥70% stenosis in all subjects (OR: 40.85; 95% CI: 6.28-265.90; p < 0.001). In the validation set, the score had an area under the receiver-operating characteristic curve of 0.91 (p < 0.001) for ≥70% stenosis. At an optimal cutoff, the score had 89% sensitivity, 77% specificity, 74% positive predictive value (PPV), 91% negative predictive value (NPV), and 82% accuracy for ≥70% stenosis. Partitioning the score into three levels of predicted risk, 91% of subjects could be identified or excluding CAD (81% PPV and 84% NPV)., Conclusion: We described an MCG score with high accuracy for predicting the presence of anatomically significant CAD.

Background/objectives: Magnetocardiography (MCG) has been proposed as a non-invasive and functional technique with high accuracy for diagnosis of myocardial ischemia. This study sought to investigate the incremental diagnostic value of combined quantitative and qualitative parameters of MCG to detect coronary artery disease (CAD)., Methods: Ninety six patients with suspected CAD who underwent coronary angiography were enrolled in the analysis to test the diagnostic accuracy of 2 MCG parameters (a quantitative parameter of the percent change of ST-segment fluctuation score and a qualitative parameter of non-dipole phenomenon)., Results: The best cut-off value for the percent change of ST-segment fluctuation score was -51.0%. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 78.1, 73.9, 82.0, 79.1, and 77.4, in the percent change of ST-segment fluctuation score and 86.5, 84.8, 88.0, 86.7, and 86.3 in non-dipole phenomenon. The area under the curve of receiver-operating characteristics was 0.79 for the percent change of ST-segment fluctuation score and 0.86 for non-dipole phenomenon (p<0.001). However, the incorporation of non-dipole phenomenon into a model with the percent change of ST-segment fluctuation score significantly improved C-statistics, indicating the enhancement of diagnostic performance in the detection of significant CAD (0.790 to 0.930; p<0.001)., Conclusions: Qualitative assessment of non-dipole phenomenon has a better diagnostic value than the quantitative parameter of percent change of ST-segment fluctuation score in the detection of significant CAD. Furthermore, this study found that the incorporation of non-dipole phenomenon into the percent change of ST-segment fluctuation score significantly improved the diagnostic performance of CAD detection., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background and Objective: Smoking is a common risk factor for coronary artery disease (CAD) and chronic obstructive pulmonary disease (COPD). We evaluated the prevalence of undiagnosed COPD in patients with CAD and assessed the relationship between airflow obstruction and markers of cardiac stress., Methods: We recruited prospectively consecutive patients aged >40 years without known history of chronic lung disease (e.g. asthma, COPD, bronchiectasis) who had undergone percutaneous coronary intervention (PCI) for obstructive CAD between August 2009 and October 2010. Spirometry was performed and serum ST2, a novel biomarker of cardiomyocyte stress and fibrosis, was measured by enzyme-linked immunosorbent assay., Results: Among 475 subjects (mean age 64 ± 9.7, range 42-85 years, 87.2% males, 58.5% current or ex-smokers) who underwent spirometry, 51 (10.7%) had undiagnosed airflow obstruction with FEV1 /FVC ratio <70%. Of these 51 subjects, 14 (2.9%), 23 (4.8%) and 14 (2.9%) had FEV1 ≥80, 50-80 and 30-50% predicted normal, respectively. ST2 level was measured in all the subjects with undiagnosed airflow obstruction and in 290 subjects with normal lung function. There was no significant difference in left ventricular ejection fraction on echocardiogram between subjects with and without airflow obstruction. Patients with severe airflow obstruction had a higher level of cardiac stress marker ST2 than those with mild and moderate airflow obstruction (rho = -0.214, P ≤ 0.001)., Conclusion: Undiagnosed airflow obstruction is common among patients with CAD who have undergone PCI. Severity of airflow limitation is associated with increasing cardiac stress., (© 2015 Asian Pacific Society of Respirology.)

Background: Although magnetocardiography (MCG) has been proposed as a non-invasive technique with high accuracy for functional diagnosis of myocardial injury, the validation of MCG against fractional flow reserve FFR in diagnosing coronary artery disease (CAD) has not yet been established. The goal of the study was to determine the diagnostic accuracy of MCG versus invasively determined FFR in patients with suspected or known CAD., Methods: Forty seven patients with suspected CAD (35 men; mean age 69 years) who underwent coronary angiography and FFR measurement were enrolled. FFR ≤ 0.8 was considered to indicate significant myocardial ischemia. The change of ST-segment fluctuation score from rest to stress was calculated from the MCG. In addition, two blinded cardiologists assessed MCG images that were visualized by post-processing method, bull's-eye mapping., Results: The best cut-off value of the percent change of ST-segment fluctuation score was -39.0% with sensitivity of 86.7% and specificity of 73.9%. Sensitivity, specificity, diagnostic accuracy, and the area under the receiver-operator characteristics curve of bull's-eye mapping for the detection of significant CAD were 90.5%, 92.3%, 91.5%, and 0.914 on a patient basis and 90.0%, 93.8%, 92.3%, and 0.919 by coronary territory, respectively., Conclusions: MCG accurately detects functionally significant CAD as defined by using FFR, provides an assessment of ischemic status in agreement with the change of ST-segment fluctuation score, and accurately localizes the ischemic territory in bull's eye mapping. Therefore, MCG may provide an incremental value for prediction of myocardial ischemia non-invasively and safely in clinical practice with fast examination time.

We studied 403 consecutive patients with non-ST-segment elevation myocardial infarction (NSTEMI). This population was divided into tertiles according to the SYNTAX score (SXscore). The high SXscore group was defined as an SXscore ≥13, and the low SXscore group as an SXscore <13. The total bilirubin (sTB) and direct bilirubin levels of patients were significantly higher in the high SXscore group (P = .001 and P = .007, respectively). There was a correlation between sTB and SXscore (r = .495; P = .005). On multivariate linear regression analyses, age (β = .100; P = .041), sTB levels (β = .171; P = .005), low-density lipoprotein cholesterol (β = .121; P = .014), and troponin-I (β = .124; P = .011) remained independent correlates of high SXscore. The mean follow-up period was 18.2 months. All-cause mortality rate was higher in the high SXscore group but did not reach significance (P = .058). In conclusion, high sTB level is independently associated with severity of coronary artery disease in patients with NSTEMI. However, no association was found with long-term mortality.

The present study aims to evaluate LV (left ventricular) mechanical dyssynchrony in CAD (coronary artery disease) with preserved and depressed EF (ejection fraction). Echocardiography with TDI (tissue Doppler imaging) was performed in 311 consecutive CAD patients (94 had preserved EF > or =50% and 217 had depressed EF <50%) and 117 healthy subjects to determine LV systolic and diastolic dyssynchrony by measuring Ts-SD (S.D. of time to peak myocardial systolic velocity during the ejection period) and Te-SD (S.D. of time to peak myocardial early diastolic velocity during the filling period) respectively, using a six-basal/six-mid-segmental model. In CAD patients with preserved EF, both Ts-SD (32.2+/-17.3 compared with 17.7+/-8.6 ms; P<0.05) and Te-SD (26.2+/-13.6 compared with 20.3+/-8.1 ms; P<0.05) were significantly prolonged when compared with controls, although they were less prolonged than CAD patients with depressed EF (Ts-SD, 37.8+/-16.5 ms; and Te-SD, 36.0+/-23.9 ms; both P<0.005). Patients with preserved EF who had no prior MI (myocardial infarction) had Ts-SD (32.9+/-17.5 ms) and Te-SD (28.6+/-14.8 ms) prolonged to a similar extent (P=not significant) to those with prior MI (Ts-SD, 28.4+/-16.8 ms; and Te-SD, 25.5+/-15.0 ms). Patients with class III/IV angina or multi-vessel disease were associated with more severe mechanical dyssynchrony (P<0.05). Furthermore, the majority of patients with mechanical dyssynchrony had narrow QRS complexes in those with preserved EF. This is in contrast with patients with depressed EF in whom systolic and diastolic dyssynchrony were more commonly associated with wide QRS complexes. In conclusion, LV mechanical dyssynchrony is evident in CAD patients with preserved EF, although it was less prevalent than those with depressed EF. In addition, mechanical dyssynchrony occurred in CAD patients without prior MI and narrow QRS complexes.