Background Patients with heart failure were candidates for cardiac resynchronization therapy （CRT） regardless of underlying aetiology. This study observed the effect of CRT in patients with ischaemic or nonischaemic...Background Patients with heart failure were candidates for cardiac resynchronization therapy （CRT） regardless of underlying aetiology. This study observed the effect of CRT in patients with ischaemic or nonischaemic cardiomyopathy. Methods One hundred and forty-two patients with refractory chronic heart failure and left bundle branch block received cardiac resynchronization therapy, 91 men and 51 women, average age 60 years. Left ventricular ejection fraction （LVEF） was severely depressed （mean 29%）, left ventricular end diastolic diameter （LVEDD） enlarged （mean 72 mm） and QRS width was lengthened （mean 147 ms）. Ninety-eight had nonischaemic cardiomyopathy and 44 had ischaemic cardiomyopathy. Results After cardiac resynchronization therapy, the heart function was significantly improved. The mean LVEF increased from 29% to 36% after pacing. In patients with nonischaemic cardiomyopathy, the LVEF was improved from 28% to 37%, and in patients with ischaemic cardiomyopathy, the LVEF was improved from 30% to 36%. No significant difference of the improvement was found between the two groups （P〉0.05）. Conclusions Cardiac resynchronization therapy could significantly improve cardiac function in patients with chronic heart failure regardless of the underlying heart disease.展开更多
Objective To analyze the unipolar electrogram from successful and unsuccessful ablation sites of focal atrial tachycardia (AT), and to evaluate its value in the identification of successful targets.Methods Fifteen con...Objective To analyze the unipolar electrogram from successful and unsuccessful ablation sites of focal atrial tachycardia (AT), and to evaluate its value in the identification of successful targets.Methods Fifteen consecutive patients with focal AT were referred for radiofrequency catheter ablation (RFCA). Both unipolar (from the tip electrode of ablating catheter) and bipolar (from the distal pair of electrode of ablating catheter) electrograms were used to identify the ablation targets of focal AT.Results Successful ablation was echieved in 14 patients. Radiofrequency energy was delivered at a total of 27 sites. The bipolar electrograms associated with successful ablation sites showed earlier atrial deflection relative to P wave onset (36 ms±15 ms vs 30 ms±11 ms, P <0.05) than the electrograms associated with failed ablation sites. At the 14 successful ablation sites, the unipolar electrograms displayed a completely negative atrial wave (“QS” morphology ) beginning with intrinsic deflection. However, at the 13 unsuccessful ablation sites,a “rS” morphology of atrial wave was shown on the unipolar electrogram.Conclusion The “QS” morphology of the atrial wave on unipolar electrograms appears to represent a reliable marker for identifying the successful ablation targets of focal AT, with a high sensitivity and specificity .展开更多
文摘Background Patients with heart failure were candidates for cardiac resynchronization therapy （CRT） regardless of underlying aetiology. This study observed the effect of CRT in patients with ischaemic or nonischaemic cardiomyopathy. Methods One hundred and forty-two patients with refractory chronic heart failure and left bundle branch block received cardiac resynchronization therapy, 91 men and 51 women, average age 60 years. Left ventricular ejection fraction （LVEF） was severely depressed （mean 29%）, left ventricular end diastolic diameter （LVEDD） enlarged （mean 72 mm） and QRS width was lengthened （mean 147 ms）. Ninety-eight had nonischaemic cardiomyopathy and 44 had ischaemic cardiomyopathy. Results After cardiac resynchronization therapy, the heart function was significantly improved. The mean LVEF increased from 29% to 36% after pacing. In patients with nonischaemic cardiomyopathy, the LVEF was improved from 28% to 37%, and in patients with ischaemic cardiomyopathy, the LVEF was improved from 30% to 36%. No significant difference of the improvement was found between the two groups （P〉0.05）. Conclusions Cardiac resynchronization therapy could significantly improve cardiac function in patients with chronic heart failure regardless of the underlying heart disease.
文摘Objective To analyze the unipolar electrogram from successful and unsuccessful ablation sites of focal atrial tachycardia (AT), and to evaluate its value in the identification of successful targets.Methods Fifteen consecutive patients with focal AT were referred for radiofrequency catheter ablation (RFCA). Both unipolar (from the tip electrode of ablating catheter) and bipolar (from the distal pair of electrode of ablating catheter) electrograms were used to identify the ablation targets of focal AT.Results Successful ablation was echieved in 14 patients. Radiofrequency energy was delivered at a total of 27 sites. The bipolar electrograms associated with successful ablation sites showed earlier atrial deflection relative to P wave onset (36 ms±15 ms vs 30 ms±11 ms, P <0.05) than the electrograms associated with failed ablation sites. At the 14 successful ablation sites, the unipolar electrograms displayed a completely negative atrial wave (“QS” morphology ) beginning with intrinsic deflection. However, at the 13 unsuccessful ablation sites,a “rS” morphology of atrial wave was shown on the unipolar electrogram.Conclusion The “QS” morphology of the atrial wave on unipolar electrograms appears to represent a reliable marker for identifying the successful ablation targets of focal AT, with a high sensitivity and specificity .
