Correction to: Magnetocardiographic recognition of abnormal depolarization and repolarization in patients with coronary artery lesions caused by Kawasaki disease.

In the original publication of the article, the sentence "The integral value was computed for each channel, and isointegral maps were constructed during depolarization and repolarization." was published incorrectly under the abstract section.

Magnetocardiographic recognition of abnormal depolarization and repolarization in patients with coronary artery lesions caused by Kawasaki disease.

Myocardial ischemia changes the electrophysiological properties of the myocardium, but it is difficult to detect the abnormalities of depolarization and repolarization noninvasively in patients with coronary artery disease. Depolarization and repolarization abnormalities were retrospectively investigated in 61 patients (48 males and 13 females) with coronary artery lesions (CALs) caused by Kawasaki disease (KD) from 2007 to 2014 using magnetocardiography (MCG). CAL had been diagnosed by selective coronary angiography. Current arrow maps (CAMs) were constructed during depolarization and repolarization [corrected]. The MCG findings were compared between the stenotic lesions group (SL group) and the non-stenotic lesions group (non-SL group). The incidence of MCG abnormalities was significantly higher in the SL group than in the non-SL group (p < 0.0001). The incidence of abnormal repolarization was significantly higher than that of abnormal depolarization (p < 0.0001). The number of coronary artery occlusions significantly affected the severity of abnormal repolarization (p = 0.02). Six (75%) of the patients with abnormal depolarization had a previous anteroseptal myocardial infarction. The transmural myocardial infarction affects on abnormalities of depolarization, and the non-transmural myocardial infarction might relate on abnormalities of repolarization. The myocardial electrical properties were preserved in patients except very severe coronary stenosis. MCG is possible to detect electrical myocardial abnormalities noninvasively in patients with CALs caused by KD.

Subtraction magnetocardiogram for detecting coronary heart disease.

BACKGROUND: A large-scale magnetocardiogram (MCG) database was produced, and standard MCG waveforms of healthy patients were calculated by using this database. It was clarified that the standard MCG waveforms are formed with the same shape and current distribution in healthy patients. A new subtraction method for detecting abnormal ST-T waveforms in coronary heart disease (CHD) patients by using the standard MCG waveform was developed. METHODS: We used MCGs of 56 CHD patients (63 ± 3 years old) and 101 age-matched normal control patients (65 ± 5 years old). To construct a subtracted ST-T waveform, we used standard MCG waveforms produced from 464 normal MCGs (male: 268, female: 196). The standard MCG waveforms were subtracted from each subject's measured MCGs, which were shortened or lengthened and normalized to adjust to the data length and magnitude of the standard waveform. We evaluated the maximum amplitude and maximum current-arrow magnitude of the subtracted ST-T waveform. RESULTS: The maximum magnetic field, maximum magnitude of current arrows, and maximum magnitude of total current vector increased according to the number of coronary artery lesions. The sensitivity and specificity of detecting CHD and normal control patients were 74.6% and 84.1%, respectively. CONCLUSIONS: The subtraction MCG method can be used to detect CHD with high accuracy, namely, sensitivity of 74.6% and specificity of 84.1% (in the case of maximum amplitude of total current vector). Furthermore, the subtraction MCG magnitude and its current distribution can reflect the expanse of the ischemic lesion area and the progress from ischemia to myocardial infarction.

Body mass index is a useful predictor of prognosis after left ventricular assist system implantation.

BACKGROUND: The obesity paradox has recently attracted considerable interest in the study of many diseases. In this investigation we examine the relationship between body mass index (BMI) and prognosis after left ventricular assist system (LVAS) implantation. METHODS: We measured the BMI of 64 patients 3 months after LVAS implantation for end-stage heart failure. The patients were classified according to BMI into Group A (BMI <16 kg/m(2)), Group B (BMI 16 to 18.4 kg/m(2)) or Group C (BMI > or =18.5 kg/m(2)). We compared the prognosis among these three groups after a mean follow-up period of 583 days. RESULTS: Seven patients were weaned from their LVAS, 24 received heart transplantation, 25 died on the transplant waiting list, and 8 remain on the list. Long-term (>1 year) mortality was significantly higher in Group A than in Groups B and C (59% vs 40% and 18%, respectively; p < 0.05). The incidence of sepsis was also significantly higher in Group A than in Groups B and C (68% vs 45% and 32%, respectively; p < 0.05). After multivariate adjustment, BMI <16 kg/m(2) (hazard ratio [HR] 14.9; 95% confidence interval [CI] 2.61 to 86.0; p < 0.01) and levels of C-reactive protein (HR 1.56; 95% CI 1.15 to 2.13; p < 0.01) were independent predictors of mortality. CONCLUSIONS: A lower BMI indicated a poor prognosis, as well as a higher incidence of a fatal complication, sepsis, after LVAS implantation. Control of BMI could be an effective way to improve management of patients with LVAS.

Standard template of adult magnetocardiogram.

BACKGROUND: We need to know the magnetocardiogram (MCG) features regarding waveform and two-dimensional current distribution in normal subjects in order to classify the abnormal waveform in patients with heart disease. However, a standard MCG waveform has not been produced yet, therefore, we have first made the standard template MCG waveform. METHODS AND RESULTS: We used data from 464 normal control subjects' 64-channel MCGs (268 males, 196 females) to produce a template MCG waveform. The measured data were averaged after shortening or lengthening and normalization. The time interval and amplitude of the averaged data were adjusted to mean values obtained from a database. Furthermore, the current distributions (current arrow maps [CAMs]) were calculated from the produced templates to determine the current distribution pattern. The produced template of the QRS complex had a typical shape in six regions that we defined (M1, M2, M3, M4, M5, and M6). In the P wave, the main current arrow in CAMs pointing in a lower-left direction appeared in M1. In the QRS complex, the typical wave appeared in each region, and there were two main current arrows in M2 and M5. There were negative T waves in M1, M4, and M5, and positive T waves in M3 and M6, and the main current arrow pointing in a lower-left direction appeared in M2. CONCLUSION: Template MCG waveforms were produced. These morphologic features were classified into six regions, and the current distribution was characterized in each region. Consequently, the templates and classifications enable understanding MCG features and writing clinical reports.