乔青
中国医学科学院阜外医院 心律失常诊治中心
BACKGROUND:P-wave dispersion (PWD) is a useful predictor of paroxysmal atrial fibrillation (AF). The effect of cardiac resynchronization therapy (CRT) on PWD and the prognostic implications of the improvement in PWD remain undefined. The aim of the study was to explore the clinical significance of the improvement of PWD after CRT.METHODS:Electrocardiographic studies were performed before and three months after CRT in 81 patients (57 men and 24 women; age (60.5 ± 11.2) years) with standard CRT indication but no history of AF. A significant improvement of PWD (PWD responder) was defined as a relative decrease ≥ 20% from baseline PWD. The primary endpoints were new-onset AF detected by electrocardiogram (ECG) or CRT.RESULTS:After (30.6 ± 7.5) months of follow-up, PWD responders (n = 43) had a significantly lower incidence of AF than did PWD nonresponders, 12% vs. 29% (P < 0.001). In Cox proportional hazard analysis, PWD responders was the only predictor of lower risk of new-onset AF (HR 0.33, 95% confidence interval 0.12 - 0.96, P = 0.033).CONCLUSION:Improvement of P-wave dispersion after CRT was associated with a lower incidence of AF, which may be related to the significant improvement in left ventricular systolic function and the reverse modeling of the left atrium.
Chinese medical journal 2012
BACKGROUND:Although cardiac resynchronization therapy (CRT) is already an established treatment, the characteristics of patients who have an excellent response to CRT and those who get no benefit remain to be determined. The purpose of this study was to search for potential predictors of both non-response and super-response to CRT.METHODS:Seventy-six consecutive patients who received CRT treatment were divided into group A (non-responders), group C (super-responders) and group B (responders exclusive of super-responders). Student's t test, Mann-Whitney test, Logistic regression and receiver operating characteristic curve were employed to identify potential predictors among the patients' demographic characteristics, clinical features, several electrocardiographic parameters before and after CRT implantation, and their pre-implant echocardiographic parameters.RESULTS:Group A had the lowest 3-month left ventricular ejection fraction (LVEF). Group C had the smallest pre-implant left ventricular end-diastolic dimension (LVEDD), the shortest post-implant QRS duration, the smallest 3-month LVEDD and the highest 3-month LVEF. In addition, there was a trend of gradual change in percent of left bundle branch block, severity of pre-implant mitral regurgitation, pre-implant QRS dispersion, post-implant QRS duration as well as post-implant QRS dispersion from group A to group B and from group B to group C. Multivariable Logistic analysis revealed that only pre-implant LVEDD could predict CRT super-response. A pre-implant LVEDD of 68.5 mm was the cut-off value that identified super-responders with 87.5% sensitivity and 79.7% specificity. A pre-implant LVEDD of 62.5 mm identified super-responders with 50.0% sensitivity and 89.8% specificity.CONCLUSIONS:Predictors of a CRT non-response remain unclear at present. But it is credible that patients with a smaller left ventricle would have a better chance to become super-responders to CRT.
Chinese medical journal 2011
BACKGROUND:The Medtronic InSync Sentry is the first available cardiac resynchronization therapy defibrillator (CRT-D) which can monitor fluid status by measuring intrathoracic impedance. This study was designed to observe the effectiveness of intrathoracic impedance monitoring on detecting aggravation of heart failure.METHODS:We retrospectively analyzed the clinical data of 14 consecutive patients. Patients were regularly followed up every 3 - 6 months after the implantation. At each visit, interrogation of the device was done. Patients were instructed to inform the researcher on hearing the device alert, and to take extra 40 milligrams of furosemidum if they had aggravated symptoms later. If the symptoms could not be relieved, they were asked to see a doctor. Data about heart failure hospitalization were collected from the medical record.RESULTS:During 18 - 48 months follow-up, a total of 7 patients encountered 28 alert events. On one hand, alert events appeared before all deteriorated symptoms and heart failure hospitalizations. On the other hand, there were 23 alerts followed by deterioration of heart failure symptoms, and 2 alerts related to 2 hospitalizations caused by pulmonary infection in one patient. Only 5 patients were hospitalized 10 times for deterioration of cardiac function.CONCLUSION:The function of intrathoracic impedance monitoring is reliable in predicting deterioration of heart failure.
Chinese medical journal 2011
BACKGROUND:Paced QRS duration, a good marker of ventricular asynchrony while pacing, has been accepted as a valuable predictor of new-onset heart failure in patients receiving right ventricular apical pacing. But nowadays we have little evidence for predicting paced QRS duration before the implantation.HYPOTHESIS:There might be relationships between paced QRS duration and demographic characteristics, clinical features such as comorbidities, native QRS duration, or preimplant cardiac size. The purpose of this article was to identify potential predictors of paced QRS duration in patients receiving right ventricular apical pacing for complete atrioventricular block.METHODS:One hundred seventy patients with right ventricular apical pacing for complete atrioventricular block were divided into 2 groups according to whether the paced QRS duration was longer than 170 ms or not. Demographic characteristics, clinical features, electrocardiogram and echocardiography before implantation, and electrocardiogram immediately after implantation, were retrospectively recorded.RESULTS:Preimplant left ventricular end-diastolic dimension (LVEDD) and body weight were found to be independently associated with the paced QRS duration. Although both of them had low sensitivity and specificity in predicting paced QRS duration longer than 170 ms, the specificity could increase to 81.2% when they were combined.CONCLUSIONS:Both preimplant LVEDD and body weight independently associate with paced QRS duration in patients receiving apical pacing for complete atrioventricular block. Although whether they really have an effect on new-onset heart failure still needs to be verified, and these findings might be a good indication.
Clinical cardiology 2010
