Techniques for automated local activation time annotation and conduction velocity estimation in cardiac mapping

Localized changes in myocardial conduction velocity (CV) are pro-arrhythmic, but high-resolution mapping of local CV is not yet possible during clinical electrophysiology procedures. This is in part because measurement of local CV at small spatial scales (1 mm) requires accurate annotation of local activation time (LAT) differences with very high temporal resolution (≤1 ms), beyond that of standard clinical methods. We sought to develop a method for high-resolution measurement of LAT differences and validate against existing techniques. First, we use a simplified theoretical model to identify a quantitative relationship between the LAT difference of a pair of electrodes and the peak amplitude of the bipolar EGM measured between them. This allows LAT differences to be calculated from bipolar EGM peak amplitude, by a novel “Determination of EGM Latencies by Transformation of Amplitude” (DELTA) method. Next, we use simulated EGMs from a computational model to validate this method. With 1 kHz sampling, LAT differences less than 4 ms were more accurately measured with DELTA than by standard LAT annotation (mean error 3.8% vs. 22.9%). In a 1-dimensional and a 2-dimension model, CV calculations were more accurate using LAT differences found by the DELTA method than by standard LAT annotation (by unipolar dV/dt timing). DELTA-derived LAT differences were more accurate than standard LAT annotation in simulated complex fractionated EGMs from a model incorporating fibrosis. Finally, we validated the DELTA method in vivo using 18,740 bipolar EGMs recorded from the left atrium of 10 atrial fibrillation patients undergoing catheter ablation. Using clinical EGMs, there was agreement in LAT differences found by DELTA, standard LAT annotation, and unipolar waveform cross-correlation. These results demonstrate an underlying relationship between a bipolar EGM’s peak amplitude and the activation time difference between its two electrodes. Our computational modeling and clinical results suggest this relationship can be leveraged clinically to improve measurement accuracy for small LAT differences, which may improve CV measurement at small spatial scales.

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Dynamic Local Activation Time Mapping in Heavily Scarred Left Atrium and Persistent Atrial Fibrillation: A proof of concept case report

Journal of Atrial Fibrillation ◽

10.4022/jafib.2415 ◽

2020 ◽

Vol 13 (2) ◽

Author(s):

Dhanunjaya Lakkireddy

Keyword(s):

Atrial Fibrillation ◽

Case Report ◽

Left Atrium ◽

Persistent Atrial Fibrillation ◽

Proof Of Concept ◽

Activation Time ◽

Local Activation ◽

Local Activation Time

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การสร้างภาพสามมิติ (3D Mapping) ในกลุ่มผู้ป่วยภาวะหัวใจเต้นผิดจังหวะชนิดเร็วที่ได้รับการรักษาโดยการจี้ด้วยกระแสไฟฟ้า (Ablation)

Siriraj Medical Bullentin ◽

10.33192/smb.v14i3.249578 ◽

2021 ◽

Vol 14 (3) ◽

pp. 53-60

Author(s):

Chatyapa Sriprom ◽

Supaluck Kanjanauthai ◽

Anon Jantanukul

Keyword(s):

3D Mapping ◽

Rf Ablation ◽

Activation Time ◽

Hybrid Technology ◽

Local Activation ◽

Bipolar Voltage ◽

Voltage Mapping ◽

Atrial Electrogram ◽

Local Activation Time ◽

Complex Fractionated Atrial Electrogram

ในปัจจุบันการสร้างภาพสามมิติ (3D Mapping) ในกลุ่มผู้ป่วยภาวะหัวใจเต้นผิดจังหวะชนิดเร็วที่ได้รับการรักษาโดยการจี้ด้วยกระแสไฟฟ้า (RF Ablation) ได้รับความนิยมอย่างแพร่หลายมากขึ้น เนื่องจากการสร้างภาพสามมิติ มีการนำเทคโนโลยีสมัยใหม่เข้ามาช่วยในการสร้างภาพได้แก่ Magnetic Technology, Current-based technology, Hybrid technology ทำให้สามารถสร้างภาพสามมิติออกมาได้หลายรูปแบบอย่างเช่น Anatomical mapping, Local Activation Time mapping (LAT), Bipolar Voltage mapping, Complex Fractionated Atrial Electrogram (CFAEs) Map, Pace map, Merge หรือ Fusion, Reentrant map เป็นต้นโดยภาพที่ได้นอกจากจะแสดงเป็นภาพนิ่งแล้วยังสามารถแสดงเป็น Video Animation ได้อีกด้วยอย่างเช่น Propagation Map, Ripple Map เป็นต้น ทำให้มีความแม่นยำในการรักษา ผู้ป่วยได้รับปริมาณรังสีที่น้อยลง มีความปลอดภัย และลดภาวะแทรกซ้อน ซึ่งก่อให้เกิดประโยชน์สูงสุดแก่ผู้ป่วย คำสำคัญ: การสร้างภาพสามมิติ, การจี้ด้วยกระแสไฟฟ้า

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Clinical validation of automatic local activation time annotation during focal premature ventricular complex ablation procedures

EP Europace ◽

10.1093/europace/eux306 ◽

2017 ◽

Vol 20 (FI2) ◽

pp. f171-f178 ◽

Cited By ~ 2

Author(s):

Juan Acosta ◽

David Soto-Iglesias ◽

Juan Fernández-Armenta ◽

Manuel Frutos-López ◽

Beatriz Jáuregui ◽

...

Keyword(s):

Premature Ventricular Complex ◽

Clinical Validation ◽

Activation Time ◽

Local Activation ◽

Local Activation Time

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Local Activation Time Estimation in Fractionated Electrograms of Cardiac Mappings

2019 41st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC) ◽

10.1109/embc.2019.8856683 ◽

2019 ◽

Author(s):

Bahareh Abdi ◽

Alle-Jan van der Veen ◽

Natasja M. S. de Groot ◽

Richard C. Hendriks

Keyword(s):

Time Estimation ◽

Activation Time ◽

Local Activation ◽

Local Activation Time ◽

Fractionated Electrograms

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Differentiation of the right versus left outflow tract ventricular arrhythmias using local activation time at the His bundle electrogram

International Journal of Arrhythmia ◽

10.1186/s42444-020-00023-7 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Won-Seok Choe ◽

So-Ryoung Lee ◽

Myung-Jin Cha ◽

Eue-Keun Choi ◽

Seil Oh

Keyword(s):

Diagnostic Accuracy ◽

Outflow Tract ◽

Activation Time ◽

Characteristic Analysis ◽

Predictive Values ◽

Cutoff Value ◽

Local Activation ◽

His Bundle ◽

Sensitivity Specificity ◽

Local Activation Time

Abstract Background Although multiple algorithms based on surface electrocardiographic criteria have been introduced to localize idiopathic ventricular arrhythmia (VA) origins from the outflow tract (OT), their diagnostic accuracy and clinical usefulness remain limited. We evaluated whether local activation time of the His bundle region could differentiate left and right ventricular OT VA origins in the early stage of electrophysiology study. Methods We studied 30 patients who underwent catheter ablation for OT VAs with a left bundle branch block pattern and inferior axis QRS morphology. The interval between the local V signal on the mapping catheter placed in the RVOT and His bundle region (V(RVOT)-V(HB) interval) and the interval from QRS complex onset to the local V signal on the His bundle region (QRS-V(HB) interval) were measured during VAs. Results The V(RVOT)-V(HB) and QRS-V(HB) intervals were significantly shorter in patients with LVOT VAs. The area under the curve (AUC) for the V(RVOT)-V(HB) interval by receiver operating characteristic analysis was 0.865. A cutoff value of ≤ 50 ms predicted an LVOT origin of VA with sensitivity, specificity, and positive and negative predictive values of 100%, 62.5%, 40%, and 100%, respectively. The QRS-V(HB) interval showed similar diagnostic accuracy (AUC, 0.840), and a cutoff value of ≤ 15 ms predicted an LVOT origin of VA with a sensitivity, specificity, and positive and negative predictive values of 100%, 70.8%, 45.2%, and 100%, respectively. Conclusion The V(RVOT)-V(HB) and QRS-V(HB) intervals could differentiate left from right OT origins of VA with high sensitivity and negative predictive values.

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