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Jeroen J Bax - One of the best experts on this subject based on the ideXlab platform.

  • cardiac resynchronization therapy in heart failure with a narrow QRS Complex
    The New England Journal of Medicine, 2013
    Co-Authors: Frank Ruschitzka, Jeroen J Bax, John Gorcsan, William T Abraham, Josep Brugada, Jagmeet P Singh, Jeffrey S Borer, Kenneth Dickstein, Ian Ford, Daniel Gras
    Abstract:

    BACKGROUND Cardiac-resynchronization therapy (CRT) reduces morbidity and mortality in chronic systolic heart failure with a wide QRS Complex. Mechanical dyssynchrony also occurs in patients with a narrow QRS Complex, which suggests the potential usefulness of CRT in such patients. METHODS We conducted a randomized trial involving 115 centers to evaluate the effect of CRT in patients with New York Heart Association class III or IV heart failure, a left ventricular ejection fraction of 35% or less, a QRS duration of less than 130 msec, and echocardiographic evidence of left ventricular dyssynchrony. All patients underwent device implantation and were randomly assigned to have CRT capability turned on or off. The primary efficacy outcome was the composite of death from any cause or first hospitalization for worsening heart failure. RESULTS On March 13, 2013, the study was stopped for futility on the recommendation of the data and safety monitoring board. At study closure, the 809 patients who had undergone randomization had been followed for a mean of 19.4 months. The primary outcome occurred in 116 of 404 patients in the CRT group, as compared with 102 of 405 in the control group (28.7% vs. 25.2%; hazard ratio, 1.20; 95% confidence interval [CI], 0.92 to 1.57; P = 0.15). There were 45 deaths in the CRT group and 26 in the control group (11.1% vs. 6.4%; hazard ratio, 1.81; 95% CI, 1.11 to 2.93; P = 0.02). CONCLUSIONS In patients with systolic heart failure and a QRS duration of less than 130 msec, CRT does not reduce the rate of death or hospitalization for heart failure and may increase mortality. (Funded by Biotronik and GE Healthcare; EchoCRT ClinicalTrials.gov number, NCT00683696.)

  • association of intraventricular mechanical dyssynchrony with response to cardiac resynchronization therapy in heart failure patients with a narrow QRS Complex
    European Heart Journal, 2010
    Co-Authors: Rutger J Van Bommel, Martin J. Schalij, Hidekazu Tanaka, Victoria Delgado, Matteo Bertini, C J W Borleffs, Nina Ajmone Marsan, Johannes Holzmeister, Frank Ruschitzka, Jeroen J Bax
    Abstract:

    Aims Current criteria for cardiac resynchronization therapy (CRT) are restricted to patients with a wide QRS Complex (>120 ms). Overall, only 30% of heart failure patients demonstrate a wide QRS Complex, leaving the majority of heart failure patients without this treatment option. However, patients with a narrow QRS Complex exhibit left ventricular (LV) mechanical dyssynchrony, as assessed with echocardiography. To further elucidate the possible beneficial effect of CRT in heart failure patients with a narrow QRS Complex, this two-centre, non-randomized observational study focused on different echocardiographic parameters of LV mechanical dyssynchrony reflecting atrioventricular, interventricular and intraventricular dyssynchrony, and the response to CRT in these patients. Methods and results A total of 123 consecutive heart failure patients with a narrow QRS Complex (<120 ms) undergoing CRT was included at two centres. Several widely accepted measures of mechanical dyssynchrony were evaluated: LV filling ratio (LVFT/RR), LV pre-ejection time (LPEI), interventricular mechanical dyssynchrony (IVMD), opposing wall delay (OWD), and anteroseptal posterior wall delay with speckle tracking (ASPWD). Response to CRT was defined as a reduction ≥15% in left ventricular end-systolic volume at 6 months follow-up. Measures of dyssynchrony can frequently be observed in patients with a narrow QRS Complex. Nonetheless, for LVFT/RR, LPEI, and IVMD, presence of predefined significant dyssynchrony is <20%. Significant intraventricular dyssynchrony is more widely observed in these patients. With receiver operator characteristic curve analyses, both OWD and ASPWD demonstrated usefulness in predicting response to CRT in narrow QRS patients with a cut-off value of 75 and 107 ms, respectively. Conclusion Mechanical dyssynchrony can be widely observed in heart failure patients with a narrow QRS Complex. In particular, intraventricular measures of mechanical dyssynchrony may be useful in predicting LV reverse remodelling at 6 months follow-up in heart failure patients with a narrow QRS Complex, but with more stringent cut-off values than currently used in ‘wide’ QRS patients.

  • metaanalysis on effects of cardiac resynchronization therapy in heart failure patients with narrow QRS Complex
    Cardiology Journal, 2008
    Co-Authors: Vinodh Jeevanantham, Jeroen J Bax, Wojciech Zareba, Sankar D Navaneethan, David M Fitzgerald, Augusto Achilli, James P Daubert
    Abstract:

    Background: To systematically review the benefits of cardiac resynchronization therapy (CRT) in heart failure patients with narrow QRS ( Methods: We searched the MEDLINE, Cochrane Central Register of Controlled Trials, and reference lists of retrieved articles for relevant trials through October 2007. Studies were included if they were clinical trials in heart failure patients with narrow QRS Complex, had at least 3 months of duration and measured baseline mechanical dyssynchrony. Weighted mean difference (WMD) for changes in left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class and 6 minute walk distance (6MWD) at the end of follow up period were estimated using fixed effects meta-analysis. Results: Three relevant clinical trials (enrolling 98 patients) out of 80 identified studies were included in the final analysis. When compared to baseline, CRT in heart failure patients with narrow QRS Complex significantly improved mean LVEF (WMD 7.98%, 95% CI 5.94, 10.03) and 6MWD (WMD 67 m, 95% CI 39.12, 94.98) at the end of follow up period with no significant heterogeneity between the included studies (I 2 Conclusions: In patients with narrow QRS Complex and baseline mechanical asynchrony, who underwent CRT after optimal medical management, there was a significant reduction in NYHA class, improvement in LVEF and increase in 6MWD during follow up. Further data from large randomized trials are warranted to explore the role of CRT in heart failure patients with narrow QRS Complex. (Cardiol J 2008; 15: 230-236)

  • cardiac resynchronization therapy in patients with a narrow QRS Complex
    Journal of the American College of Cardiology, 2006
    Co-Authors: Gabe B Bleeker, Martin J. Schalij, Paul Steendijk, Eduard R Holman, Eric Boersma, Ernst E Van Der Wall, Jeroen J Bax
    Abstract:

    Objectives The purpose of this study was to evaluate the effects of cardiac resynchronization therapy (CRT) in heart failure patients with narrow QRS Complex ( Background Cardiac resynchronization therapy is beneficial in selected heart failure patients with wide QRS Complex (≥120 ms). Patients with narrow QRS Complex are currently not eligible for CRT, and the potential effects of CRT are not well studied. Methods Thirty-three consecutive patients with narrow QRS Complex and 33 consecutive patients with wide QRS Complex (control group) were prospectively included. All patients needed to have LV dyssynchrony ≥65 ms on TDI, New York Heart Association (NYHA) functional class III/IV heart failure, and LV ejection fraction ≤35%. Results Baseline characteristics, particularly LV dyssynchrony, were comparable between patients with narrow and wide QRS Complex (110 ± 8 ms vs. 175 ± 22 ms; p = NS). No significant relationship was observed between baseline QRS duration and LV dyssynchrony (r = 0.21; p = NS). The improvement in clinical symptoms and LV reverse remodeling was comparable between patients with narrow and wide QRS Complex (mean NYHA functional class reduction 0.9 ± 0.6 vs. 1.1 ± 0.6 [p = NS] and mean LV end-systolic volume reduction 39 ± 34 ml vs. 44 ± 46 ml [p = NS]). Conclusions Cardiac resynchronization therapy appears to be beneficial in patients with narrow QRS Complex and severe LV dyssynchrony on TDI, with similar improvement in symptoms and comparable LV reverse remodeling to patients with wide QRS Complex. The current results need confirmation in larger patient cohorts.

Andras Vereckei - One of the best experts on this subject based on the ideXlab platform.

  • current algorithms for the diagnosis of wide QRS Complex tachycardias
    Current Cardiology Reviews, 2014
    Co-Authors: Andras Vereckei
    Abstract:

    The differential diagnosis of a regular, monomorphic wide QRS Complex tachycardia (WCT) mechanism represents a great diagnostic dilemma commonly encountered by the practicing physician, which has important implications for acute arrhythmia management, further work-up, prognosis and chronic management as well. This comprehensive review discusses the causes and differential diagnosis of WCT, and since the ECG remains the cornerstone of WCT differential diagnosis, focuses on the application and diagnostic value of different ECG criteria and algorithms in this setting and also provides a practical clinical approach to patients with WCTs.

  • new algorithm using only lead avr for differential diagnosis of wide QRS Complex tachycardia
    Heart Rhythm, 2008
    Co-Authors: Andras Vereckei, Gabor Z Duray, Gabor Szenasi, Gregory T Altemose, John M Miller
    Abstract:

    Background We recently reported an ECG algorithm for differential diagnosis of regular wide QRS Complex tachycardias that was superior to the Brugada algorithm. Objective The purpose of this study was to further simplify the algorithm by omitting the complicated morphologic criteria and restricting the analysis to lead aVR. Methods In this study, 483 wide QRS Complex tachycardias [351 ventricular tachycardias (VTs), 112 supraventricular tachycardias (SVTs), 20 preexcited tachycardias] from 313 patients with proven diagnoses were prospectively analyzed by two of the authors blinded to the diagnosis. Lead aVR was analyzed for (1) presence of an initial R wave, (2) width of an initial r or q wave >40 ms, (3) notching on the initial downstroke of a predominantly negative QRS Complex, and (4) ventricular activation–velocity ratio (v i /v t ), the vertical excursion (in millivolts) recorded during the initial (v i ) and terminal (v t ) 40 ms of the QRS Complex. When any of criteria 1 to 3 was present, VT was diagnosed; when absent, the next criterion was analyzed. In step 4, v i /v t >1 suggested SVT, and v i /v t ≤1 suggested VT. Results The accuracy of the new aVR algorithm and our previous algorithm was superior to that of the Brugada algorithm ( P = .002 and P = .007, respectively). The aVR algorithm and our previous algorithm had greater sensitivity ( P P = .001, respectively) and negative predictive value for diagnosing VT and greater specificity ( P P = .001, respectively) and positive predictive value for diagnosing SVT compared with the Brugada criteria. Conclusion The simplified aVR algorithm classified wide QRS Complex tachycardias with the same accuracy as standard criteria and our previous algorithm and was superior to the Brugada algorithm.

  • application of a new algorithm in the differential diagnosis of wide QRS Complex tachycardia
    European Heart Journal, 2006
    Co-Authors: Andras Vereckei, Gabor Z Duray, Gabor Szenasi, Gregory T Altemose, John M Miller
    Abstract:

    Aims The Brugada criteria proposed to distinguish between regular, monomorphic wide QRS Complex tachycardias (WCT) caused by supraventricular (SVT) and ventricular tachycardia (VT) have been reported to have a better sensitivity and specificity than the traditional criteria. By incorporating two new criteria, a new, simplified algorithm was devised and compared with the Brugada criteria. Methods and results A total of 453 WCTs (331 VTs, 105 SVTs, 17 pre-excited tachycardias) from 287 consecutive patients with a proven electrophysiological (EP) diagnosis were prospectively analysed by two of the authors blinded to the EP diagnosis. The following criteria were analysed: (i) presence of AV dissociation; (ii) presence of an initial R wave in lead aVR; (iii) whether the morphology of the WCT correspond to bundle branch or fascicular block; (iv) estimation of initial ( v i) and terminal ( v t) ventricular activation velocity ratio ( v i/ v t) by measuring the voltage change on the ECG tracing during the initial 40 ms ( v i) and the terminal 40 ms ( v t) of the same bi- or multiphasic QRS Complex. A v i/ v t >1 was suggestive of SVT and a v i/ v t ≤1 of VT. An initial R wave in lead aVR suggested VT. The overall test accuracy of the new algorithm was superior ( P = 0.006) to that of the Brugada criteria. The new algorithm had a greater sensitivity ( P < 0.001) and (−) predictive value (NPV) for VT diagnosis, and specificity ( P = 0.0471) and (+) predictive value (PPV) for SVT diagnosis than those of the Brugada criteria [both NPV for VT diagnosis and PPV for SVT diagnosis were: 83.5% (95% confidence interval = CI 75.9–91.1%) for the new vs. 65.2% (95% CI 56.5–73.9%) for the Brugada algorithms]. Conclusion The new algorithm is a highly accurate tool for correctly diagnosing the cause of WCT ECGs.

John M Miller - One of the best experts on this subject based on the ideXlab platform.

  • new algorithm using only lead avr for differential diagnosis of wide QRS Complex tachycardia
    Heart Rhythm, 2008
    Co-Authors: Andras Vereckei, Gabor Z Duray, Gabor Szenasi, Gregory T Altemose, John M Miller
    Abstract:

    Background We recently reported an ECG algorithm for differential diagnosis of regular wide QRS Complex tachycardias that was superior to the Brugada algorithm. Objective The purpose of this study was to further simplify the algorithm by omitting the complicated morphologic criteria and restricting the analysis to lead aVR. Methods In this study, 483 wide QRS Complex tachycardias [351 ventricular tachycardias (VTs), 112 supraventricular tachycardias (SVTs), 20 preexcited tachycardias] from 313 patients with proven diagnoses were prospectively analyzed by two of the authors blinded to the diagnosis. Lead aVR was analyzed for (1) presence of an initial R wave, (2) width of an initial r or q wave >40 ms, (3) notching on the initial downstroke of a predominantly negative QRS Complex, and (4) ventricular activation–velocity ratio (v i /v t ), the vertical excursion (in millivolts) recorded during the initial (v i ) and terminal (v t ) 40 ms of the QRS Complex. When any of criteria 1 to 3 was present, VT was diagnosed; when absent, the next criterion was analyzed. In step 4, v i /v t >1 suggested SVT, and v i /v t ≤1 suggested VT. Results The accuracy of the new aVR algorithm and our previous algorithm was superior to that of the Brugada algorithm ( P = .002 and P = .007, respectively). The aVR algorithm and our previous algorithm had greater sensitivity ( P P = .001, respectively) and negative predictive value for diagnosing VT and greater specificity ( P P = .001, respectively) and positive predictive value for diagnosing SVT compared with the Brugada criteria. Conclusion The simplified aVR algorithm classified wide QRS Complex tachycardias with the same accuracy as standard criteria and our previous algorithm and was superior to the Brugada algorithm.

  • application of a new algorithm in the differential diagnosis of wide QRS Complex tachycardia
    European Heart Journal, 2006
    Co-Authors: Andras Vereckei, Gabor Z Duray, Gabor Szenasi, Gregory T Altemose, John M Miller
    Abstract:

    Aims The Brugada criteria proposed to distinguish between regular, monomorphic wide QRS Complex tachycardias (WCT) caused by supraventricular (SVT) and ventricular tachycardia (VT) have been reported to have a better sensitivity and specificity than the traditional criteria. By incorporating two new criteria, a new, simplified algorithm was devised and compared with the Brugada criteria. Methods and results A total of 453 WCTs (331 VTs, 105 SVTs, 17 pre-excited tachycardias) from 287 consecutive patients with a proven electrophysiological (EP) diagnosis were prospectively analysed by two of the authors blinded to the EP diagnosis. The following criteria were analysed: (i) presence of AV dissociation; (ii) presence of an initial R wave in lead aVR; (iii) whether the morphology of the WCT correspond to bundle branch or fascicular block; (iv) estimation of initial ( v i) and terminal ( v t) ventricular activation velocity ratio ( v i/ v t) by measuring the voltage change on the ECG tracing during the initial 40 ms ( v i) and the terminal 40 ms ( v t) of the same bi- or multiphasic QRS Complex. A v i/ v t >1 was suggestive of SVT and a v i/ v t ≤1 of VT. An initial R wave in lead aVR suggested VT. The overall test accuracy of the new algorithm was superior ( P = 0.006) to that of the Brugada criteria. The new algorithm had a greater sensitivity ( P < 0.001) and (−) predictive value (NPV) for VT diagnosis, and specificity ( P = 0.0471) and (+) predictive value (PPV) for SVT diagnosis than those of the Brugada criteria [both NPV for VT diagnosis and PPV for SVT diagnosis were: 83.5% (95% confidence interval = CI 75.9–91.1%) for the new vs. 65.2% (95% CI 56.5–73.9%) for the Brugada algorithms]. Conclusion The new algorithm is a highly accurate tool for correctly diagnosing the cause of WCT ECGs.

  • differential diagnosis of wide QRS Complex tachycardia
    Cardiac Electrophysiology (Fourth Edition)#R##N#From Cell to Bedside, 2004
    Co-Authors: John M Miller, Mithilesh K Das, Rishi Arora, Cesar Albertelista
    Abstract:

    “I should know this!” These words, or ones conveying a similar meaning, are often uttered by a physician who is given a sick patient's electrocardiogram (ECG) that shows a wide QRS Complex tachycardia (WCT). Despite a wealth of established criteria, the diagnosis of a WCT remains difficult for the practicing physician. Making the correct diagnosis is important not only for choosing appropriate initial therapy to terminate the arrhythmia episode but also for subsequent management. For example, many physicians assume that a WCT in a patient who is alert and hemodynamically stable must be supraventricular tachycardia (SVT) because “the condition of patients with ventricular tachycardia (VT) is always unstable.” If the rhythm is actually VT in a patient with reduced systolic function and an injection of verapamil is given for treatment of presumed SVT, severe and prolonged hypotension may result, and a stable situation can quickly become very unstable. An incorrect initial diagnosis can also set the wrong course for chronic therapy with potentially disastrous results. Thus, arriving at the correct diagnosis of the cause of WCT is more than an intellectual exercise.

Richard L Verrier - One of the best experts on this subject based on the ideXlab platform.

  • flecainide induced QRS Complex widening correlates with negative inotropy
    Heart Rhythm, 2021
    Co-Authors: Ana Rabelo B Evangelista, Felipe R Monteiro, Bruce D Nearing, Luiz Belardinelli, Richard L Verrier
    Abstract:

    Background The negative inotropic effect of Class IC antiarrhythmic drugs limits their use for acute cardioversion of atrial fibrillation (AF). Objective The purpose of this study was to examine, in an intact porcine model, the effects of pulmonary and intravenous (IV) administration of flecainide on left ventricular (LV) contractility and QRS Complex width at doses that are effective in converting new-onset AF to sinus rhythm. Methods Flecainide (1.5 mg/kg bolus) was delivered by intratracheal administration and compared to 2.0 mg/kg 10-minute IV administration (European Society of Cardiology guideline) and to 0.5 and 1.0 mg/kg 2-minute IV doses in 40 closed-chest, anesthetized Yorkshire pigs. Catheters were fluoroscopically positioned in the LV to monitor QRS Complex width and contractility and at the bifurcation of the main bronchi to deliver intratracheal flecainide. Results Peak flecainide plasma concentrations (Cmax) were similar, but the 30-minute area under the curve (AUC) of plasma levels was 1.4- to 2.8-fold greater for 2.0 mg/kg 10-minute IV infusion than for the lower, more rapidly delivered intratracheal and IV doses. AUC for LV contractility (ie, negative inotropic burden) was 2.2- to 3.6-fold greater for 2.0 mg/kg 10-minute IV dose than for the lower, more rapidly delivered doses. QRS Complex widening by flecainide was highly correlated with the decrease in LV contractility (r2 = 0.890, P Conclusion QRS Complex widening in response to flecainide is strongly correlated with decrease in LV contractility. Rapid pulmonary or IV flecainide delivery reduces the negative inotropic burden while quickly achieving Cmax levels associated with conversion of AF.

  • preimplantation interlead ecg heterogeneity is superior to QRS Complex duration in predicting mechanical super response in patients with non left bundle branch block receiving cardiac resynchronization therapy
    Heart Rhythm, 2020
    Co-Authors: Bruce D Nearing, Richard L Verrier, Alexandre L Bortolotto, Alexandre A Marum, Bruna Araujo Silva
    Abstract:

    BACKGROUND Reliable quantitative preimplantation predictors of response to cardiac resynchronization therapy (CRT) are needed. OBJECTIVE We tested the utility of preimplantation R-wave and T-wave heterogeneity (RWH and TWH, respectively) compared to standard QRS Complex duration in identifying mechanical super-responders to CRT and mortality risk. METHODS We analyzed resting 12-lead electrocardiographic recordings from all 155 patients who received CRT devices between 2006 and 2018 at our institution and met class I and IIA American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines with echocardiograms before and after implantation. Super-responders (n=35, 23%) had ≥20% increase in left ventricular ejection fraction and/or ≥20% decrease in left ventricular end-systolic diameter and were compared with non-super-responders (n=120, 77%), who did not meet these criteria. RWH and TWH were measured using second central moment analysis. RESULTS Among patients with non-left bundle branch block (LBBB), preimplantation RWH was significantly lower in super-responders than in non-super-responders in 3 of 4 lead sets (P=.001 to P=.038) and TWH in 2 lead sets (both, P=.05), with the corresponding areas under the curve (RWH: 0.810-0.891, P<.001; TWH: 0.759-0.810, P≤.005). No differences were observed in the LBBB group. Preimplantation QRS Complex duration also did not differ between super-responders and non-super-responders among patients with (P=.856) or without (P=.724) LBBB; the areas under the curve were nonsignificant (both, P=.69). RWHV1-3LILII ≥ 420 μV predicted 3-year all-cause mortality in the entire cohort (P=.037), with a hazard ratio of 7.440 (95% confidence interval 1.015-54.527; P=.048); QRS Complex duration ≥ 150 ms did not predict mortality (P=.27). CONCLUSION Preimplantation interlead electrocardiographic heterogeneity but not QRS Complex duration predicts mechanical super-response to CRT in patients with non-LBBB.

Bruna Araujo Silva - One of the best experts on this subject based on the ideXlab platform.

  • preimplantation interlead ecg heterogeneity is superior to QRS Complex duration in predicting mechanical super response in patients with non left bundle branch block receiving cardiac resynchronization therapy
    Heart Rhythm, 2020
    Co-Authors: Bruce D Nearing, Richard L Verrier, Alexandre L Bortolotto, Alexandre A Marum, Bruna Araujo Silva
    Abstract:

    BACKGROUND Reliable quantitative preimplantation predictors of response to cardiac resynchronization therapy (CRT) are needed. OBJECTIVE We tested the utility of preimplantation R-wave and T-wave heterogeneity (RWH and TWH, respectively) compared to standard QRS Complex duration in identifying mechanical super-responders to CRT and mortality risk. METHODS We analyzed resting 12-lead electrocardiographic recordings from all 155 patients who received CRT devices between 2006 and 2018 at our institution and met class I and IIA American College of Cardiology/American Heart Association/Heart Rhythm Society guidelines with echocardiograms before and after implantation. Super-responders (n=35, 23%) had ≥20% increase in left ventricular ejection fraction and/or ≥20% decrease in left ventricular end-systolic diameter and were compared with non-super-responders (n=120, 77%), who did not meet these criteria. RWH and TWH were measured using second central moment analysis. RESULTS Among patients with non-left bundle branch block (LBBB), preimplantation RWH was significantly lower in super-responders than in non-super-responders in 3 of 4 lead sets (P=.001 to P=.038) and TWH in 2 lead sets (both, P=.05), with the corresponding areas under the curve (RWH: 0.810-0.891, P<.001; TWH: 0.759-0.810, P≤.005). No differences were observed in the LBBB group. Preimplantation QRS Complex duration also did not differ between super-responders and non-super-responders among patients with (P=.856) or without (P=.724) LBBB; the areas under the curve were nonsignificant (both, P=.69). RWHV1-3LILII ≥ 420 μV predicted 3-year all-cause mortality in the entire cohort (P=.037), with a hazard ratio of 7.440 (95% confidence interval 1.015-54.527; P=.048); QRS Complex duration ≥ 150 ms did not predict mortality (P=.27). CONCLUSION Preimplantation interlead electrocardiographic heterogeneity but not QRS Complex duration predicts mechanical super-response to CRT in patients with non-LBBB.