Cardiac resynchronization therapy （CRT） is associated with a favorable outcome only in patients with left bundle branch block （LBBB） pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB...Cardiac resynchronization therapy （CRT） is associated with a favorable outcome only in patients with left bundle branch block （LBBB） pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular （LV） region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance （NICD） pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern.展开更多
The ear-xiphisternum distance (EXD, the distance from the low edge of the ear to the xiphisternal basis in supine position) was used as a reference value for esophageal catheter insertion. ECGs recorded in the esophag...The ear-xiphisternum distance (EXD, the distance from the low edge of the ear to the xiphisternal basis in supine position) was used as a reference value for esophageal catheter insertion. ECGs recorded in the esophagus with bipolar electrocardiography using standard limb lead (ESLL) and conventional unipolar lead (ECUL) were compared. 112 patients with sinus rhythm and 76 patients during paroxysmal supraventricular tachycardia (PSVT) whose P-wave and QRS complex did not overlap were studied. The results suggested that in sinus rhythm the amplitude of the P-wave in ESLL was larger and the T-wave was smaller than in ECUL. During PSVT, the P-wave was much clear and higher in each lead of ESLL than that in ECUL. The ideal range of esophageal ECG recording was situated between the end of EXD and 6. 5 cm proximal to it.展开更多
Objective: To identify electrocardiographic parameters that predict extent of early improvement in ejection fraction (EF) in patients with stress cardiomyopathy. Methods: We collected baseline clinical, ECG and imagin...Objective: To identify electrocardiographic parameters that predict extent of early improvement in ejection fraction (EF) in patients with stress cardiomyopathy. Methods: We collected baseline clinical, ECG and imaging data and follow up echocardiography data on 30 consecutive patients with stress cardiomyopathy. The relationship between baseline ECG parameters and Delta EF was evaluated by univariate and multivariable analysis. Results: Median EF improved from 35% to 55% (p < 0.0001). Delta EF showed negative correlation with number of leads with T inversion (p = 0.01) and QT interval (p = 0.02). The number of leads with T inversion was independently associated with Delta EF (coefficient ?4.878, p = 0.04). Conclusion: The number of leads with T wave inversion is negatively correlated with and is an independent predictor of the extent of early improvement of EF in patients with stress cardiomyopathy. Hence the ECG at initial presentation can be used as a simple tool to predict LV function recovery.展开更多
Patients with chronic obstructive pulmonary disease(COPD)have an increased risk for cardiovascular events,and electrocardiography has an important role in detecting cardiac side effects of COPD-related hypoxia.
文摘Cardiac resynchronization therapy （CRT） is associated with a favorable outcome only in patients with left bundle branch block （LBBB） pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular （LV） region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance （NICD） pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern.
文摘The ear-xiphisternum distance (EXD, the distance from the low edge of the ear to the xiphisternal basis in supine position) was used as a reference value for esophageal catheter insertion. ECGs recorded in the esophagus with bipolar electrocardiography using standard limb lead (ESLL) and conventional unipolar lead (ECUL) were compared. 112 patients with sinus rhythm and 76 patients during paroxysmal supraventricular tachycardia (PSVT) whose P-wave and QRS complex did not overlap were studied. The results suggested that in sinus rhythm the amplitude of the P-wave in ESLL was larger and the T-wave was smaller than in ECUL. During PSVT, the P-wave was much clear and higher in each lead of ESLL than that in ECUL. The ideal range of esophageal ECG recording was situated between the end of EXD and 6. 5 cm proximal to it.
文摘Objective: To identify electrocardiographic parameters that predict extent of early improvement in ejection fraction (EF) in patients with stress cardiomyopathy. Methods: We collected baseline clinical, ECG and imaging data and follow up echocardiography data on 30 consecutive patients with stress cardiomyopathy. The relationship between baseline ECG parameters and Delta EF was evaluated by univariate and multivariable analysis. Results: Median EF improved from 35% to 55% (p < 0.0001). Delta EF showed negative correlation with number of leads with T inversion (p = 0.01) and QT interval (p = 0.02). The number of leads with T inversion was independently associated with Delta EF (coefficient ?4.878, p = 0.04). Conclusion: The number of leads with T wave inversion is negatively correlated with and is an independent predictor of the extent of early improvement of EF in patients with stress cardiomyopathy. Hence the ECG at initial presentation can be used as a simple tool to predict LV function recovery.
文摘Patients with chronic obstructive pulmonary disease(COPD)have an increased risk for cardiovascular events,and electrocardiography has an important role in detecting cardiac side effects of COPD-related hypoxia.
