The Application of Multichannel ECG Analytic System in Cardiovascular Diseases
The Application of Multichannel ECG Analytic System in Cardiovascular Diseases
Cardiovascular disease (CVD) is the leading cause of death worldwide. Most individuals with
 CVD show no evidence of disease for decades as the disease progresses before the first onset
 of symptoms, often a "sudden" heart attack, finally arises. The spatial repolarization
 heterogeneity within the ventricular myocardium had been proposed to represent the function
 of the heart in health and disease. Greater than normal levels of repolarization dispersion
 may allow early diagnosis of CVD. There is a growing interest in the characteristic features
 of ventricular repolarization that leads to lethal ventricular arrhythmia even with the use
 of non-antiarrhythmic drugs. The recovery time dispersion may reflect a repolarization
 heterogeneity leading to lethal ventricular arrhythmia. Previously, the investigators had
 utilized a 64-channel low-TC SQUID MCG device to develop and verify 2 parameters, so called
 smooth index of QTc (SIQTc) and T wave propagation (TWP), to accurately detect and localize
 the myocardial ischemia. Recently Nakai, et al. reported that a newly developed 187-ch
 signal-averaged vector-projected ECG (187-ch SAVP-ECG) could evaluate low-amplitude
 high-frequency potentials and repolarization heterogeneity. In this project, the
 investigators'll try to modify and improve the spatial resolution of ECG signals from a
 Self-built-in multichannel ECG system with a newly developed algorithm, and also try to
 derive the SIQTc and TWP from this system, for early detection of CVD. The investigators
 intend to prove the concept that this newly developed multichannel ECG system could
 efficiently detect or diagnose CVD with acceptable sensitivity and specificity, and in a
 portable way.
Cardiovascular disease (CVD) is the leading cause of death worldwide. Most individuals with
 CVD show no evidence of disease for decades as the disease progresses before the first onset
 of symptoms, often a "sudden" heart attack, finally arises. The spatial repolarization
 heterogeneity within the ventricular myocardium had been proposed to represent the function
 of the heart in health and disease. Greater than normal levels of repolarization dispersion
 may allow early diagnosis of CVD. There is a growing interest in the characteristic features
 of ventricular repolarization that leads to lethal ventricular arrhythmia even with the use
 of non-antiarrhythmic drugs. The recovery time dispersion may reflect a repolarization
 heterogeneity leading to lethal ventricular arrhythmia. Although cheap and convenient, the
 traditional 12-leads electrocardiogram (ECG) is frequently normal at rest in such patients.
 The quantification of repolarization heterogeneity with ECG, QT dispersion, has some
 methodological limitations and has been abandoned in daily practice. Many studies have shown
 that body surface potential mapping (BSPM) contains more diagnostic and prognostic
 information than that elicited from a 12-lead ECG. The BSPM and magnetocardiogram (MCG) are
 two new developed recording methods, and provide higher spatial resolution than traditional
 ECG signals but with the disadvantages of high cost and huge volume. It is impossible to be
 used in a portable way. Previously, the investigators had utilized a 64-channel low-TC SQUID
 MCG device to develop and verify 2 parameters, so called smooth index of QTc (SIQTc) and T
 wave propagation (TWP), to accurately detect and localize the myocardial ischemia. Recently
 Nakai, et al. reported that a newly developed 187-ch signal-averaged vector-projected ECG
 (187-ch SAVP-ECG) could evaluate low-amplitude high-frequency potentials and repolarization
 heterogeneity. In this project, the investigators'll try to modify and improve the spatial
 resolution of ECG signals from a Self-built-in multichannel ECG system with a newly developed
 algorithm, and also try to derive the SIQTc and TWP from this system, for early detection of
 CVD. The investigators intend to prove the concept that this newly developed multichannel ECG
 system could efficiently detect or diagnose CVD with acceptable sensitivity and specificity,
 and in a portable way.
Inclusion Criteria:

 -  Patients older than 20 years old.

 -  with suspected arrhythmia or cardiovascular diseases.

 Exclusion criteria

 -  NO