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P-Wave and QRS-Complex Durations Can be Measured Automatically from Far-Field Implantable Cardioverter Defibrillator Electrograms
The 16th Annual Scientific Meeting
HFSA
S53
a retrospective study, we did review the data on a total of 1663 patients with different grades of diastolic dysfunction that was diagnosed by an echocardiogram. Analysis of the ECG was done in 1063 patients using an ECG done within 48 hours from the echocardiogram. The parameters included QTc interval (QTcO430 msec), QRS complex (O100 mes), and PR interval duration (!200 msec), as well as the axis. 63% of the patients had QTc prolongation (n5 672, average QTc 461 msec), 392 patients had normal QTc (average QTc 410 mes). The analysis was statistically significant (P!005). The Analysis of the PR interval was done from a total number of 1004 patients. 10% of the patients had PR prolongation (n5107). The statistical analysis was not significant. Analysis of the QRS complex duration was done from a total number of 1061 patients, 81% of the patients had normal QRS duration (n5863), 9% had prolonged QRSO120 msec and 10% had borderline QRS prolongation (100-120 msec). The statistical analysis was not significant. Analysis of the axis deviation was done from a total number of 968 patients, 81% had normal axis (n5788), 17% had left axis deviation only 2% with right axis deviation. The statistical analysis was not significant. Conclusion: The most common ECG manifestation of diastolic dysfunction is a prolonged QTc interval. All other ECG parameters reviewed were not significant.
171
169 P-Wave and QRS-Complex Durations Can be Measured Automatically from Far-Field Implantable Cardioverter Defibrillator Electrograms Saul Greenhut1, Alex Sambelashvili1, Vadim Levin2, Robin Germany3; 1Medtronic, Inc., Mounds View, MN; 2Lehigh Valley Hospital, Allentown, PA; 3University of Oklahoma, Oklahoma City, OK Background: ECG P-wave and QRS-complex durations characterize atrial and ventricular conduction and are used in clinical practice for diagnostics. QRS duration $120 ms is an indication for Cardiac Resynchronization Therapy (CRT). Studies suggest that ECG P-wave and QRS duration can be used to optimize CRT device programming. Objective: To determine whether automatically measured device intracardiac electrogram (EGM) conduction intervals can be used as a surrogate for ECG conduction intervals to identify patients for CRT and optimize CRT device programming. Methods: A 5-lead surface ECG and device telemetered signals, which included marker channel, Can-SVC (Superior Vena Cava coil) EGM, and Can-RAr (right atrial ring electrode) EGM, were digitally recorded from CRT patients (n585) during intrinsic ventricular activation with or without atrial pacing. A Wave Duration Measurement (WDM) algorithm was developed to automatically measure sensed (Ps) or paced P-waves (Pp) and sensed QRS conduction intervals (QRSs) from the EGMs as the interval from the device sensed or pacing marker to the end of the respective wave. The WDM results were compared to the corresponding P and QRS conduction intervals manually measured from the surface ECG using Pearson correlation analysis and mean absolute difference (MADIFF). Manual wave measurements were performed twice by the same expert to evaluate intra-observer variability. Results: Automatically determined wave conduction intervals correlated with manually measured values (Table). Intra-observer MADIFFs for the manually measured Ps, Pp and QRSs from surface ECGs were 1167 ms, 11614 ms and 967 ms respectively, comparable to the accuracy of the automatic measurements. Conclusion: The study demonstrated the feasibility of determining sensed or paced P and sensed QRS conduction intervals from far-field EGMs which may then be used to identify patients for CRT and optimize CRT parameters.
Comparison of Cardiac Resynchronization Therapy Optimization Methods with Respect to Biventricular Pacing Percentage: Sub-Analysis of Adaptive CRT Trial Bernd Lemke1, David Birnie2, Kazutaka Aonuma3, Mahmoud Houmsse4, Alex Sambelashvili5; 1Luedenscheid Clinic, Luedenscheid, Germany; 2University of Ottawa Heart Institute, Ottawa, ON, Canada; 3Tsukuba University Hospital, Tsukuba, Japan; 4Ohio State University, Columbus, OH; 5Medtronic Inc., Mounds View, MN Background: A greater percent of bi-ventricular (BiV) pacing in CRT is associated with superior survival and clinical outcomes. Pacing is inhibited when the device atrio-ventricular (AV) delay is longer than the intrinsic AV conduction interval. CardioSync is an automatic CRT optimization method, which determines the optimal AV delay based on the measurement of intrinsic AV and P-wave intervals. We aimed to compare CardioSync to echocardiographic (echo) optimization with respect to cardiac function and percent BiV pacing lost due to AV programming. Methods: Data from the treatment arm of the randomized double-blind Adaptive CRT trial was used for the analysis. Within 2 weeks after the CRT implant each patient underwent AV optimization using CardioSync and the echo iterative method. Echo Aortic Velocity Time Integral (AoVTI) was determined at the two settings. The device was then uploaded with software which measured the intrinsic AV interval every minute over 6 months and stored the values in the device memory. Percent pacing lost due to AV delay programmed by CardioSync and by echo was calculated in each patient as a percent of intrinsic AV intervals that were shorter than the corresponding optimal AV delay. Optimization by both methods and AoVTI measurements were repeated at 6-month follow-up. Results: Intrinsic AVs were obtained in 313 patients (age565611 years, 69% male, 94% NYHA class III, Left-Ventricular Ejection Fraction524.766.6%, QRS duration5154621 ms). Loss of BiV pacing was significantly lower with CardioSync compared to echo optimization (Table). AoVTIs for the two programming approaches were similar with high Concordance Correlation Coefficient (CCC) at post-implant (CCC50.93, 95% CI: 0.91-0.94) and 6-month followup (CCC50.90, 95% CI: 0.87-0.92). Conclusions: CardioSync reduces loss of BiV pacing due to inappropriate AV programming, while producing similar cardiac performance as echo optimization. Effect of AV Programming Method on the Loss of % BiV Pacing and Cardiac Performance
Correlation Coefficients (R) and Mean Absolute Differences (MADIFF) Between Manual and WDM Algorithm Measurements Electrocardiographic Wave
Sensed P-wave (Ps) Paced P-wave (Pp) Sensed QRS-wave (QRSs) Sensed P-wave (Ps) Paced P-wave (Pp) Sensed QRS-wave (QRSs)
Correlation Coefficient R (p-value) Can-SVC 0.89 (p!0.0001) 0.68 (p!0.0001) 0.75 (p!0.0001) Can-RAr 0.38 (p50.03) 0.60 (p50.004) 0.66 (p!0.0001)
MADIFF 6 StdDev (ms)
867 1367 16613 16613 13613 22614
170 Electrocardiographic (ECG) Manifestations of Diastolic Dysfunction Wissam Khalife, Mohamed Morsy, Poorna Nalabothu, Adnan Khan, Syed Hussain, Sangeeta Mutnuri; Cardiology, University of Texas Medical Branch, Galveston, TX Background: The effects of diastolic dysfunction on the ECG are not well known and few studies previously addressed the same question but with small sample size and only one parameter was evaluated. The aim of our study is to evaluate multiple ECG criteria that might be affected by diastology. Methods/Results: As a part of
% BiV pacing lost Number (%) of patients with # 90% BiV pacing AoVTI at post-implant (cm) AoVTI at 6-month follow-up (cm)
CardioSync optimization
Echo optimization
P-value
0.29% 0 (0%)
2.8% 14 (4.47%)
0.00036 !0.0001
17.866.0 17.865.2
18.066.2 18.065.2
0.18 0.20
172 Optimal Atrio-Ventricular Delay in CRT Patients Can Be Approximated from Surface ECG P-Wave Duration Vadim Levin1, Mehdi Razavi2, Robert Call3, Alex Sambelashvili3, James Coles3; 1 Lehigh Valley Hospital, Allentown, PA; 2Texas Heart Institute/St. Luke’s Episcopal Hospital, Houston, TX; 3Medtronic, Inc, Mounds View, MN Cardiac Resynchronization Therapy (CRT) is an established treatment for systolic heart failure with ventricular conduction delays. Optimization of the programmed atrio-ventricular delay (AV) may result in better CRT outcomes. Previous studies have shown positive correlation between inter-atrial conduction time (IACT) and optimal AV. We hypothesized that P-wave duration can be used as a surrogate for IACT and, hence, for AV optimization.
HFSA
S53
a retrospective study, we did review the data on a total of 1663 patients with different grades of diastolic dysfunction that was diagnosed by an echocardiogram. Analysis of the ECG was done in 1063 patients using an ECG done within 48 hours from the echocardiogram. The parameters included QTc interval (QTcO430 msec), QRS complex (O100 mes), and PR interval duration (!200 msec), as well as the axis. 63% of the patients had QTc prolongation (n5 672, average QTc 461 msec), 392 patients had normal QTc (average QTc 410 mes). The analysis was statistically significant (P!005). The Analysis of the PR interval was done from a total number of 1004 patients. 10% of the patients had PR prolongation (n5107). The statistical analysis was not significant. Analysis of the QRS complex duration was done from a total number of 1061 patients, 81% of the patients had normal QRS duration (n5863), 9% had prolonged QRSO120 msec and 10% had borderline QRS prolongation (100-120 msec). The statistical analysis was not significant. Analysis of the axis deviation was done from a total number of 968 patients, 81% had normal axis (n5788), 17% had left axis deviation only 2% with right axis deviation. The statistical analysis was not significant. Conclusion: The most common ECG manifestation of diastolic dysfunction is a prolonged QTc interval. All other ECG parameters reviewed were not significant.
171
169 P-Wave and QRS-Complex Durations Can be Measured Automatically from Far-Field Implantable Cardioverter Defibrillator Electrograms Saul Greenhut1, Alex Sambelashvili1, Vadim Levin2, Robin Germany3; 1Medtronic, Inc., Mounds View, MN; 2Lehigh Valley Hospital, Allentown, PA; 3University of Oklahoma, Oklahoma City, OK Background: ECG P-wave and QRS-complex durations characterize atrial and ventricular conduction and are used in clinical practice for diagnostics. QRS duration $120 ms is an indication for Cardiac Resynchronization Therapy (CRT). Studies suggest that ECG P-wave and QRS duration can be used to optimize CRT device programming. Objective: To determine whether automatically measured device intracardiac electrogram (EGM) conduction intervals can be used as a surrogate for ECG conduction intervals to identify patients for CRT and optimize CRT device programming. Methods: A 5-lead surface ECG and device telemetered signals, which included marker channel, Can-SVC (Superior Vena Cava coil) EGM, and Can-RAr (right atrial ring electrode) EGM, were digitally recorded from CRT patients (n585) during intrinsic ventricular activation with or without atrial pacing. A Wave Duration Measurement (WDM) algorithm was developed to automatically measure sensed (Ps) or paced P-waves (Pp) and sensed QRS conduction intervals (QRSs) from the EGMs as the interval from the device sensed or pacing marker to the end of the respective wave. The WDM results were compared to the corresponding P and QRS conduction intervals manually measured from the surface ECG using Pearson correlation analysis and mean absolute difference (MADIFF). Manual wave measurements were performed twice by the same expert to evaluate intra-observer variability. Results: Automatically determined wave conduction intervals correlated with manually measured values (Table). Intra-observer MADIFFs for the manually measured Ps, Pp and QRSs from surface ECGs were 1167 ms, 11614 ms and 967 ms respectively, comparable to the accuracy of the automatic measurements. Conclusion: The study demonstrated the feasibility of determining sensed or paced P and sensed QRS conduction intervals from far-field EGMs which may then be used to identify patients for CRT and optimize CRT parameters.
Comparison of Cardiac Resynchronization Therapy Optimization Methods with Respect to Biventricular Pacing Percentage: Sub-Analysis of Adaptive CRT Trial Bernd Lemke1, David Birnie2, Kazutaka Aonuma3, Mahmoud Houmsse4, Alex Sambelashvili5; 1Luedenscheid Clinic, Luedenscheid, Germany; 2University of Ottawa Heart Institute, Ottawa, ON, Canada; 3Tsukuba University Hospital, Tsukuba, Japan; 4Ohio State University, Columbus, OH; 5Medtronic Inc., Mounds View, MN Background: A greater percent of bi-ventricular (BiV) pacing in CRT is associated with superior survival and clinical outcomes. Pacing is inhibited when the device atrio-ventricular (AV) delay is longer than the intrinsic AV conduction interval. CardioSync is an automatic CRT optimization method, which determines the optimal AV delay based on the measurement of intrinsic AV and P-wave intervals. We aimed to compare CardioSync to echocardiographic (echo) optimization with respect to cardiac function and percent BiV pacing lost due to AV programming. Methods: Data from the treatment arm of the randomized double-blind Adaptive CRT trial was used for the analysis. Within 2 weeks after the CRT implant each patient underwent AV optimization using CardioSync and the echo iterative method. Echo Aortic Velocity Time Integral (AoVTI) was determined at the two settings. The device was then uploaded with software which measured the intrinsic AV interval every minute over 6 months and stored the values in the device memory. Percent pacing lost due to AV delay programmed by CardioSync and by echo was calculated in each patient as a percent of intrinsic AV intervals that were shorter than the corresponding optimal AV delay. Optimization by both methods and AoVTI measurements were repeated at 6-month follow-up. Results: Intrinsic AVs were obtained in 313 patients (age565611 years, 69% male, 94% NYHA class III, Left-Ventricular Ejection Fraction524.766.6%, QRS duration5154621 ms). Loss of BiV pacing was significantly lower with CardioSync compared to echo optimization (Table). AoVTIs for the two programming approaches were similar with high Concordance Correlation Coefficient (CCC) at post-implant (CCC50.93, 95% CI: 0.91-0.94) and 6-month followup (CCC50.90, 95% CI: 0.87-0.92). Conclusions: CardioSync reduces loss of BiV pacing due to inappropriate AV programming, while producing similar cardiac performance as echo optimization. Effect of AV Programming Method on the Loss of % BiV Pacing and Cardiac Performance
Correlation Coefficients (R) and Mean Absolute Differences (MADIFF) Between Manual and WDM Algorithm Measurements Electrocardiographic Wave
Sensed P-wave (Ps) Paced P-wave (Pp) Sensed QRS-wave (QRSs) Sensed P-wave (Ps) Paced P-wave (Pp) Sensed QRS-wave (QRSs)
Correlation Coefficient R (p-value) Can-SVC 0.89 (p!0.0001) 0.68 (p!0.0001) 0.75 (p!0.0001) Can-RAr 0.38 (p50.03) 0.60 (p50.004) 0.66 (p!0.0001)
MADIFF 6 StdDev (ms)
867 1367 16613 16613 13613 22614
170 Electrocardiographic (ECG) Manifestations of Diastolic Dysfunction Wissam Khalife, Mohamed Morsy, Poorna Nalabothu, Adnan Khan, Syed Hussain, Sangeeta Mutnuri; Cardiology, University of Texas Medical Branch, Galveston, TX Background: The effects of diastolic dysfunction on the ECG are not well known and few studies previously addressed the same question but with small sample size and only one parameter was evaluated. The aim of our study is to evaluate multiple ECG criteria that might be affected by diastology. Methods/Results: As a part of
% BiV pacing lost Number (%) of patients with # 90% BiV pacing AoVTI at post-implant (cm) AoVTI at 6-month follow-up (cm)
CardioSync optimization
Echo optimization
P-value
0.29% 0 (0%)
2.8% 14 (4.47%)
0.00036 !0.0001
17.866.0 17.865.2
18.066.2 18.065.2
0.18 0.20
172 Optimal Atrio-Ventricular Delay in CRT Patients Can Be Approximated from Surface ECG P-Wave Duration Vadim Levin1, Mehdi Razavi2, Robert Call3, Alex Sambelashvili3, James Coles3; 1 Lehigh Valley Hospital, Allentown, PA; 2Texas Heart Institute/St. Luke’s Episcopal Hospital, Houston, TX; 3Medtronic, Inc, Mounds View, MN Cardiac Resynchronization Therapy (CRT) is an established treatment for systolic heart failure with ventricular conduction delays. Optimization of the programmed atrio-ventricular delay (AV) may result in better CRT outcomes. Previous studies have shown positive correlation between inter-atrial conduction time (IACT) and optimal AV. We hypothesized that P-wave duration can be used as a surrogate for IACT and, hence, for AV optimization.