The Experts below are selected from a list of 8433 Experts worldwide ranked by ideXlab platform
James C Fang - One of the best experts on this subject based on the ideXlab platform.
-
effect of QRS morphology on clinical event reduction with cardiac resynchronization therapy meta analysis of randomized controlled trials
American Heart Journal, 2012Co-Authors: Ilke Sipahi, Douglas Y Rowland, Josephine C Chou, Marshall Hyden, Daniel I Simon, James C FangAbstract:Background: Cardiac resynchronization therapy (CRT) is effective in reducing clinical events in patients with heart failure and prolonged QRS Interval. Studies using surrogate measures and subgroup analysis of large trials suggest that only patients with severely prolonged QRS benefit from CRT. Our objective was to determine whether the effect of CRT on adverse clinical events (eg, death, hospitalizations) is different in patients with moderately (ie, 120-149 milliseconds) vs severely (ie,150 milliseconds) prolonged QRS duration. Methods: Searches of MEDLINE, SCOPUS, and Cochrane databases were conducted for randomized controlled CRT trials. Trials reporting clinical events according to different QRS ranges were identified. Five randomized trials fulfilling the inclusion criteria (total patients, n=5813) were included in the meta-analysis. Results: In patients with severely prolonged QRS, there was a reduction in composite clinical events with CRT (risk ratio, 0.60; 95% confidence Interval [CI], 0.530.67) (P.001). In contrast, there was no benefit of CRT in patients with moderately prolonged QRS (RR, 0.95; 95% CI, 0.82-1.10) (P=.49), resulting in a significantly different impact of CRT in the 2 QRS groups (P.001). There was a significant relationship between baseline QRS duration and risk ratio (P.001) with benefit of CRT appearing at a QRS of approximately 150 milliseconds and above. The differential response of the 2 QRS groups was evident for all New York Heart Association classes. Conclusions: Cardiac resynchronization therapy was effective in reducing adverse clinical events in patients with heart failure and a baseline QRS Interval of 150 milliseconds or greater, but CRT did not reduce events in patients with a QRS of less than 150 milliseconds. These findings have implications for the selection of patients for CRT.
-
indications for cardiac resynchronization therapy 2011 update from the heart failure society of america guideline committee
Journal of Cardiac Failure, 2012Co-Authors: William G Stevenson, Peter E Carson, James C Fang, Adrian F Hernandez, Stuart D Katz, John A Spertus, Nancy K Sweitzer, Wai Hong Tang, Nancy M Albert, Javed ButlerAbstract:Cardiac resynchronization therapy (CRT) improves survival, symptoms, quality of life, exercise capacity, and cardiac structure and function in patients with New York Heart Association (NYHA) functional class II or ambulatory class IV heart failure (HF) with wide QRS complex. The totality of evidence supports the use of CRT in patients with less severe HF symptoms. CRT is recommended for patients in sinus rhythm with a widened QRS Interval (≥150 ms) not due to right bundle branch block (RBBB) who have severe left ventricular (LV) systolic dysfunction and persistent NYHA functional class II-III symptoms despite optimal medical therapy (strength of evidence A). CRT may be considered for several other patient groups for whom evidence of benefit is clinically significant but less substantial, including patients with a QRS Interval of ≥120 to <150 ms and severe LV systolic dysfunction who have persistent mild to severe HF despite optimal medical therapy (strength of evidence B), some patients with atrial fibrillation, and some with ambulatory class IV HF. Several evidence gaps remain that need to be addressed, including the ideal threshold for QRS duration, QRS morphology, lead placement, degree of myocardial scarring, and the modality for evaluating dyssynchrony. Recommendations will evolve over time as additional data emerge from completed and ongoing clinical trials.
-
impact of QRS duration on clinical event reduction with cardiac resynchronization therapy meta analysis of randomized controlled trials
JAMA Internal Medicine, 2011Co-Authors: Ilke Sipahi, Thomas P Carrigan, Douglas Y Rowland, Bruce S Stambler, James C FangAbstract:Background Cardiac resynchronization therapy (CRT) is effective in reducing clinical events in patients with heart failure and prolonged QRS Interval. Studies using surrogate measures and subgroup analysis of large trials suggest that only patients with severely prolonged QRS benefit from CRT. Our objective was to determine whether the effect of CRT on adverse clinical events (eg, death, hospitalizations) is different in patients with moderately (ie, 120-149 milliseconds) vs severely (ie, ≥150 milliseconds) prolonged QRS duration. Methods Searches of MEDLINE, SCOPUS, and Cochrane databases were conducted for randomized controlled CRT trials. Trials reporting clinical events according to different QRS ranges were identified. Five randomized trials fulfilling the inclusion criteria (total patients, n = 5813) were included in the meta-analysis. Results In patients with severely prolonged QRS, there was a reduction in composite clinical events with CRT (risk ratio, 0.60; 95% confidence Interval [CI], 0.53-0.67) (P Conclusions Cardiac resynchronization therapy was effective in reducing adverse clinical events in patients with heart failure and a baseline QRS Interval of 150 milliseconds or greater, but CRT did not reduce events in patients with a QRS of less than 150 milliseconds. These findings have implications for the selection of patients for CRT.
Ilke Sipahi - One of the best experts on this subject based on the ideXlab platform.
-
effect of QRS morphology on clinical event reduction with cardiac resynchronization therapy meta analysis of randomized controlled trials
American Heart Journal, 2012Co-Authors: Ilke Sipahi, Douglas Y Rowland, Josephine C Chou, Marshall Hyden, Daniel I Simon, James C FangAbstract:Background: Cardiac resynchronization therapy (CRT) is effective in reducing clinical events in patients with heart failure and prolonged QRS Interval. Studies using surrogate measures and subgroup analysis of large trials suggest that only patients with severely prolonged QRS benefit from CRT. Our objective was to determine whether the effect of CRT on adverse clinical events (eg, death, hospitalizations) is different in patients with moderately (ie, 120-149 milliseconds) vs severely (ie,150 milliseconds) prolonged QRS duration. Methods: Searches of MEDLINE, SCOPUS, and Cochrane databases were conducted for randomized controlled CRT trials. Trials reporting clinical events according to different QRS ranges were identified. Five randomized trials fulfilling the inclusion criteria (total patients, n=5813) were included in the meta-analysis. Results: In patients with severely prolonged QRS, there was a reduction in composite clinical events with CRT (risk ratio, 0.60; 95% confidence Interval [CI], 0.530.67) (P.001). In contrast, there was no benefit of CRT in patients with moderately prolonged QRS (RR, 0.95; 95% CI, 0.82-1.10) (P=.49), resulting in a significantly different impact of CRT in the 2 QRS groups (P.001). There was a significant relationship between baseline QRS duration and risk ratio (P.001) with benefit of CRT appearing at a QRS of approximately 150 milliseconds and above. The differential response of the 2 QRS groups was evident for all New York Heart Association classes. Conclusions: Cardiac resynchronization therapy was effective in reducing adverse clinical events in patients with heart failure and a baseline QRS Interval of 150 milliseconds or greater, but CRT did not reduce events in patients with a QRS of less than 150 milliseconds. These findings have implications for the selection of patients for CRT.
-
impact of QRS duration on clinical event reduction with cardiac resynchronization therapy meta analysis of randomized controlled trials
JAMA Internal Medicine, 2011Co-Authors: Ilke Sipahi, Thomas P Carrigan, Douglas Y Rowland, Bruce S Stambler, James C FangAbstract:Background Cardiac resynchronization therapy (CRT) is effective in reducing clinical events in patients with heart failure and prolonged QRS Interval. Studies using surrogate measures and subgroup analysis of large trials suggest that only patients with severely prolonged QRS benefit from CRT. Our objective was to determine whether the effect of CRT on adverse clinical events (eg, death, hospitalizations) is different in patients with moderately (ie, 120-149 milliseconds) vs severely (ie, ≥150 milliseconds) prolonged QRS duration. Methods Searches of MEDLINE, SCOPUS, and Cochrane databases were conducted for randomized controlled CRT trials. Trials reporting clinical events according to different QRS ranges were identified. Five randomized trials fulfilling the inclusion criteria (total patients, n = 5813) were included in the meta-analysis. Results In patients with severely prolonged QRS, there was a reduction in composite clinical events with CRT (risk ratio, 0.60; 95% confidence Interval [CI], 0.53-0.67) (P Conclusions Cardiac resynchronization therapy was effective in reducing adverse clinical events in patients with heart failure and a baseline QRS Interval of 150 milliseconds or greater, but CRT did not reduce events in patients with a QRS of less than 150 milliseconds. These findings have implications for the selection of patients for CRT.
Alan D Woolf - One of the best experts on this subject based on the ideXlab platform.
-
serial electrocardiogram changes in acute tricyclic antidepressant overdoses
Critical Care Medicine, 1997Co-Authors: Erica L Liebelt, Andy Ulrich, Paul D Francis, Alan D WoolfAbstract:Objectives: To describe the changes over time of the QRS Interval and terminal 40-msec QRS frontal axis (T40-ms) in patients with acute tricyclic antidepressant poisoning, to identify clinical factors and treatment associated with these changes, and to determine if patients with tricyclic antidepressant-related complications (seizures and/or arrhythmias) had differences in such serial electrocardiogram (ECG) changes when compared with patients without complications. Design: Prospective, observational, cohort study. Setting: Emergency departments of community and university-based hospitals in Massachusetts that consulted a large regional poison center. Patients: Thirty-six patients who presented with an acute ingestion ( 300 ng/mL. Interventions: None. Measurements and Main Results: The maximal limb-lead QRS Interval and T40-ms axis were measured manually in all ECGs. The maximum recorded QRS Interval occurred at the time of presentation for 24 (80%) of 30 patients whose QRS was ≥100 msecs and a median time of 3 hrs (range 1 to 9) for the other six patients. The maximum recorded T40-ms axis occurred at the time of presentation for 31 (86%) of 36 patients and at a median time of 3 hrs (range 1 to 5) for the remaining five patients. The minimum QRS Interval observed remained >100 msecs In 15 patients (range 100 to 140 msecs) and decreased to <100 msecs in 15 patients. The median time from presentation to the first ECG with a QRS <100 msecs was 20 hrs (range 1 to 153) in those 15 patients. There were no significant differences in clinical characteristics and treatment (including sodium bicarbonate therapy) between the two groups. The minimum recorded T40-ms remained ≥120° in 30 patients and decreased to <120° in six patients. The median time from presentation until the first ECG with a T40-ms axis <120° was 13 hrs (range 2 to 30) for the six patients. All ECG measurements were greater and remained abnormal for a significantly longer duration in those patients who developed seizures and/or ventricular arrhythmias. These two ECG parameters demonstrated ongoing changes and persistent abnormalities despite clinical improvement in all patients except one. Conclusions: The conduction abnormalities seen in severe tricyclic antidepressant toxicity vary widely in the time observed for resolution of these abnormalities and sometimes remain persistently abnormal. All ECG parameters were significantly more abnormal in those patients who developed seizures and/or arrhythmias. Clinical improvement occurred both before and during these ECG changes.
-
ecg lead avr versus QRS Interval in predicting seizures and arrhythmias in acute tricyclic antidepressant toxicity
Annals of Emergency Medicine, 1995Co-Authors: Erica L Liebelt, Paul D Francis, Alan D WoolfAbstract:Abstract Study objective: To compare the value of ECG measurements from lead aVR with the QRS-Interval duration in predicting seizures and ventricular arrhythmias due to acute tricyclic antidepressant (TCA) toxicity. Design: Prospective cohort series of referral calls from hospitals to a regional poison control center. Participants: Seventy-nine patients (mean age, 30±15 years) who presented within 24 hours of ingestion. Seizures occurred in 16 patients (20%) and ventricular arrhythmias in 5 (6%). Interventions: The amplitude of the terminal R wave in lead aVR (R aVR ), the R-wave/S-wave ratio in lead aVR (R/S aVR ), and the maximal limb-lead QRS Interval were measured on the initial ECG. Results: R aVR was greater in those patients who had seizures or arrhythmias than in those who did not (4.4 versus 1.8 mm, P <.001), as was R/S aVR (1.4 versus .5, P <.001). The sensitivity of an R aVR of 3 mm or more was 81% and that of an R/S aVR of .7 or more was 75%, compared with 82% for QRS Intervals greater than 100 milliseconds. The positive predictive value (PPV) of an R aVR of 3 mm or more was 43% and that of the R/S aVR of .7 or more 46%, compared with a PPV for QRS Interval of 100 milliseconds or more of 35%. Multiple logistic-regression analysis demonstrated that an R aVR of 3 mm or more was the only ECG variable that significantly predicted seizures and arrhythmias (OR, 6.9 [95% CI, 1.2 to 40], P =.03). Conclusion: R aVR and R/S aVR were greater in patients in whom seizures or arrhythmias developed after an acute TCA overdose. R aVR of 3 mm or more was the only ECG variable that significantly predicted these adverse outcomes. [Liebelt EL, Francis PD, Woolf AD: ECG lead aVR versus QRS Interval in predicting seizures and arrhythmias in acute tricyclic antidepressant toxicity. Ann Emerg Med August 1995;26:195-201.]
Annette Peters - One of the best experts on this subject based on the ideXlab platform.
-
Short-term effects of fine particulate matter and ozone on the cardiac conduction system in patients undergoing cardiac catheterization
Particle and Fibre Toxicology, 2018Co-Authors: Siqi Zhang, Susanne Breitner, Wayne E Cascio, Robert B Devlin, Lucas M Neas, David Diaz-sanchez, William E Kraus, Joel Schwartz, Elizabeth R Hauser, Annette PetersAbstract:Background Air pollution-induced changes in cardiac electrophysiological properties could be a pathway linking air pollution and cardiovascular events. The evidence of air pollution effects on the cardiac conduction system is incomplete yet. We investigated short-term effects of particulate matter ≤ 2.5 μm in aerodynamic diameter (PM_2.5) and ozone (O_3) on cardiac electrical impulse propagation and repolarization as recorded in surface electrocardiograms (ECG). Methods We analyzed repeated 12-lead ECG measurements performed on 5,332 patients between 2001 and 2012. The participants came from the Duke CATHGEN Study who underwent cardiac catheterization and resided in North Carolina, United States (NC, U.S.). Daily concentrations of PM_2.5 and O_3 at each participant’s home address were predicted with a hybrid air quality exposure model. We used generalized additive mixed models to investigate the associations of PM_2.5 and O_3 with the PR Interval, QRS Interval, heart rate-corrected QT Interval (QTc), and heart rate (HR). The temporal lag structures of the associations were examined using distributed-lag models. Results Elevated PM_2.5 and O_3 were associated with four-day lagged lengthening of the PR and QRS Intervals, and with one-day lagged increases in HR. We observed immediate effects on the lengthening of the QTc Interval for both PM_2.5 and O_3, as well as delayed effects for PM_2.5 (lagged by 3 – 4 days). The associations of PM_2.5 and O_3 with the PR Interval and the association of O_3 with the QRS Interval persisted until up to seven days after exposure. Conclusions In patients undergoing cardiac catheterization, short-term exposure to air pollution was associated with increased HR and delays in atrioventricular conduction, ventricular depolarization and repolarization.
-
short term effects of fine particulate matter and ozone on the cardiac conduction system in patients undergoing cardiac catheterization
Particle and Fibre Toxicology, 2018Co-Authors: Siqi Zhang, Susanne Breitner, Wayne E Cascio, Robert B Devlin, Lucas M Neas, William E Kraus, Joel Schwartz, Elizabeth R Hauser, David Diazsanchez, Annette PetersAbstract:Air pollution-induced changes in cardiac electrophysiological properties could be a pathway linking air pollution and cardiovascular events. The evidence of air pollution effects on the cardiac conduction system is incomplete yet. We investigated short-term effects of particulate matter ≤ 2.5 μm in aerodynamic diameter (PM2.5) and ozone (O3) on cardiac electrical impulse propagation and repolarization as recorded in surface electrocardiograms (ECG). We analyzed repeated 12-lead ECG measurements performed on 5,332 patients between 2001 and 2012. The participants came from the Duke CATHGEN Study who underwent cardiac catheterization and resided in North Carolina, United States (NC, U.S.). Daily concentrations of PM2.5 and O3 at each participant’s home address were predicted with a hybrid air quality exposure model. We used generalized additive mixed models to investigate the associations of PM2.5 and O3 with the PR Interval, QRS Interval, heart rate-corrected QT Interval (QTc), and heart rate (HR). The temporal lag structures of the associations were examined using distributed-lag models. Elevated PM2.5 and O3 were associated with four-day lagged lengthening of the PR and QRS Intervals, and with one-day lagged increases in HR. We observed immediate effects on the lengthening of the QTc Interval for both PM2.5 and O3, as well as delayed effects for PM2.5 (lagged by 3 – 4 days). The associations of PM2.5 and O3 with the PR Interval and the association of O3 with the QRS Interval persisted until up to seven days after exposure. In patients undergoing cardiac catheterization, short-term exposure to air pollution was associated with increased HR and delays in atrioventricular conduction, ventricular depolarization and repolarization.
Yelda Basaran - One of the best experts on this subject based on the ideXlab platform.
-
The utility of fragmented QRS complexes to predict significant intraventricular dyssynchrony in nonischemic dilated cardiomyopathy patients with a narrow QRS Interval.
The Canadian journal of cardiology, 2009Co-Authors: Kursat Tigen, Tansu Karaahmet, Emre Gurel, Cihan Cevik, Kenneth Nugent, Selçuk Pala, Ali Cevat Tanalp, Bülent Mutlu, Yelda BasaranAbstract:Background Fragmented QRS complexes in the electrocardiograms (ECGs) of patients with coronary artery disease are associated with adverse cardiac events. However, there are limited data on its predictive usefulness in patients with nonischemic dilated cardiomyopathy. Left ventricular dyssynchrony is common in heart failure patients who have wide QRS Intervals, but its frequency in patients with narrow QRS Intervals is uncertain. Objectives To investigate the relationship between fragmented QRS complexes and intraventricular dyssynchrony in patients with nonischemic dilated cardiomyopathy in sinus rhythm. Methods Sixty nonischemic dilated cardiomyopathy patients with sinus rhythm and narrow QRS Intervals were recruited. Forty patients had a fragmented QRS in their basal ECG, and 20 patients did not have a fragmented QRS. Patients were analyzed for correlation between fragmented QRS complexes and intraventricular dyssynchrony. Results The maximal difference in time to the peak myocardial systolic velocity between any two left ventricular segments (Max-ASE Sys), and maximal difference between Max-ASE Sys and the mean value of all segments (Max-ASE to Mean Sys) were significantly higher in patients with fragmented QRS complexes (P=0.001 and P=0.003, respectively). Seventy-two per cent of the patients with fragmented QRS complexes had significant left ventricular dyssynchrony; 15% of patients without fragmented QRS complexes had significant left ventricular dyssynchrony (P Conclusion Fragmentation in the resting ECG is associated with significant intraventricular dyssynchrony in patients with nonischemic cardiomyopathy, narrow QRS and sinus rhythm. Fragmentation in ECG might be useful in identifying patients who could benefit from cardiac resynchronization therapy.
