Высокого разрешения эндокарда и эпикарда Оптический отображения в Овцы модели из стрейч-индуцированной фибрилляции предсердий
Summary
В настоящем докладе содержится подробное описание методологии и результатов одновременных эндокарда и эпикарда оптических отображение электрического возбуждения в интактном левое предсердие из Langendorff-перфузии овец сердца во время стретч-индуцированной фибрилляции предсердий.
Abstract
Atrial fibrillation (AF) is a complex cardiac arrhythmia with high morbidity and mortality.1,2 It is the most common sustained cardiac rhythm disturbance seen in clinical practice and its prevalence is expected to increase in the coming years.3 Increased intra-atrial pressure and dilatation have been long recognized to lead to AF,1,4 which highlights the relevance of using animal models and stretch to study AF dynamics. Understanding the mechanisms underlying AF requires visualization of the cardiac electrical waves with high spatial and temporal resolution. While high-temporal resolution can be achieved by conventional electrical mapping traditionally used in human electrophysiological studies, the small number of intra-atrial electrodes that can be used simultaneously limits the spatial resolution and precludes any detailed tracking of the electrical waves during the arrhythmia. The introduction of optical mapping in the early 90’s enabled wide-field characterization of fibrillatory activity together with sub-millimeter spatial resolution in animal models5,6 and led to the identification of rapidly spinning electrical wave patterns (rotors) as the sources of the fibrillatory activity that may occur in the ventricles or the atria.7-9 Using combined time- and frequency-domain analyses of optical mapping it is possible to demonstrate discrete sites of high frequency periodic activity during AF, along with frequency gradients between left and right atrium. The region with fastest rotors activates at the highest frequency and drives the overall arrhythmia.10,11 The waves emanating from such rotor interact with either functional or anatomic obstacles in their path, resulting in the phenomenon of fibrillatory conduction.12 Mapping the endocardial surface of the posterior left atrium (PLA) allows the tracking of AF wave dynamics in the region with the highest rotor frequency. Importantly, the PLA is the region where intracavitary catheter-based ablative procedures are most successful terminating AF in patients,13 which underscores the relevance of studying AF dynamics from the interior of the left atrium. Here we describe a sheep model of acute stretch-induced AF, which resembles some of the characteristics of human paroxysmal AF. Epicardial mapping on the left atrium is complemented with endocardial mapping of the PLA using a dual-channel rigid borescope c-mounted to a CCD camera, which represents the most direct approach to visualize the patterns of activation in the most relevant region for AF maintenance.
Protocol
Discussion
Характеристики острого стретч-индуцированной ФП у изолированного сердца овец напоминают некоторые из свойств человеческой пароксизмальной ФП. Резкое увеличение внутри-предсердного давления в сердце овец позволяет поддерживать А. Ф. в течение длительных периодов времени, похожие на …
Divulgations
The authors have nothing to disclose.
Acknowledgements
При частичной поддержке грантов NHLBI P01-HL039707 и P01-HL087226 и Leducq Foundation (JJ, О. Б.), по испанским обществом кардиологов стипендий, Фонд Педро Барри де ла Маса и Фонд Альфонсо Мартина Эскудеро (DFR), Федерацией Французским Cardiologie (RPM), от общества ритма сердца общение премии, стипендии Японии Heart Foundation / Японского общества Электрокардиография (МГ).
Materials
| Material Name | Company | Catalogue Number |
| Euthanasia | ||
| Heparin | Sigma | H3393 |
| Propofol | Abbott | 5206-04-03 |
| Pentobarbital | Lundbeck Inc | NDC 67386-501-55 |
| Introducer 18 Gauge | Terumo | SS*FF1832 |
| Cuffed endotracheal tube (9 mm) | DRE Veterinary | #9440 |
| Fiber Optic Laryngoscope Case | DRE Veterinary | #991 |
| Fiber Optic Blade | DRE Veterinary | #984 |
| Operating Scissors | DRE Veterinary | #9702 #1944 |
| Scalpel Handle #3 Solid 4" | Roboz Surgical Instrument Co., Inc. | RS-9843 |
| Sterile Scalpel Blades | Roboz Surgical Instrument Co., Inc. | RS-9801-10 |
| Ventilation bag | Westmed | 562013 |
| Sims Scissors Curved Sharp/Blunt | Roboz Surgical Instrument Co., Inc. | RS-7035 |
| Tissue Forceps (×2) | DRE Veterinary | #1895 |
| KANTROWITZ Thoracic Forceps, 11" | Biomedical Research Instruments, Inc. | 34-1980 |
| Finochietto Large Chest Spreader | Kapp Surgical Instrument Inc. | KS-7301 |
| Thoracotomy shears | Rostfrei Solingen | |
| Plastic tray | Nalgene | Fischer |
| Optical mapping | ||
| Bonn Scissors (×2) | Roboz Surgical Instrument Co., Inc | RS-5840SC |
| Surgical silk | Fischer | 50-900-04214 |
| Micro Dissecting Forceps | Roboz Surgical Instrument Co., Inc | RS-5130 |
| Tetrapolar electrode catheters (Torq) (×4) | Medtronic Inc. | 05580SP |
| Digital sensor. Biopac Systems transducer | Biopac Systems, Inc. | RX104A |
| Biopac Systems amplifier | Biopac Systems, Inc. | DA-100C |
| Di-4-ANEPPS | Sigma-Aldrich, St. | D8604-5mg |
| Blebbistatin | Enzo Life Science International, INC. | BML-E1315-0025 |
| LittleJoe CCD video camera(×2) | SciMeasure Analytical Systems, Inc. | |
| Dual-channel rigid borescope | Everest VIT, Inc. | R10-25-0-90 |
| Perfusion pumps (×2) | Cole Parmer | GK-77920-30 |
| Temperature probe | Cole Parmer | R-08491-02 |
| pH meter | Fischer | 01-913-806 |
| Digital temperature gauge | Cole Parmer | GK89000-10 |
| Oxygenator filters | Sorin | 05318 |
| Silicon perfusion tubes (L/S 15) | MasterFlex | 96410-15 |
| Laser light guides (×6) | Oriel Corporation | 77536 |
| Liquid light-guide (0.2 in core) | Newport Corporation | 77556 |
| Laser generator (1 watt) (×1) | Shanghai Dream Lsaer Tecchnology | SDL-532-1000T |
| Laser generator (5 watt) (×1) | Spectra Physics Lasers | MILL 5sJ |
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