1
|
Natale A, Raviele A, Al-Ahmad A, Alfieri O, Aliot E, Almendral J, Breithardt G, Brugada J, Calkins H, Callans D, Cappato R, Camm JA, Della Bella P, Guiraudon GM, Haïssaguerre M, Hindricks G, Ho SY, Kuck KH, Marchlinski F, Packer DL, Prystowsky EN, Reddy VY, Ruskin JN, Scanavacca M, Shivkumar K, Soejima K, Stevenson WJ, Themistoclakis S, Verma A, Wilber D. Venice Chart International Consensus document on ventricular tachycardia/ventricular fibrillation ablation. J Cardiovasc Electrophysiol 2010; 21:339-79. [PMID: 20082650 DOI: 10.1111/j.1540-8167.2009.01686.x] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Andrea Natale
- Texas Cardiac Arrhythmia Institute, St. David's Medical Center, Austin, TX, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
2
|
Kovoor P, Daly M, Campbell C, Dewsnap B, Eipper V, Uther J, Ross D. Intramural Radiofrequency Ablation:. Effects of Electrode Temperature and Length. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2004; 27:719-25. [PMID: 15189525 DOI: 10.1111/j.1540-8159.2004.00519.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of this study was to evaluate intramural temperature-controlled radiofrequency ablation by determining the intramural temperature profile during ablation and by correlating lesion geometry with intramural electrode size and temperature. Intramural ablation might be useful to create deeper lesions for ventricular tachycardia secondary to underlying heart disease. Intramural radiofrequency ablation was performed in 17 greyhounds at thoracotomy, from an epicardial approach, using a 21-gauge needle electrode. Sixty-eight lesions were created in 11 dogs at electrode temperatures of 70 degrees C, 80 degrees C, 90 degrees C, and 100 degrees C for 60 seconds. Intramural thermocouples at 1-, 2-, 3-, 4-, and 5-mm distances were used to identify simultaneous intramural temperature profile. An epicardial approach was used to ensure accurate positioning of the ablating and temperature monitoring needles within the myocardium with fixed interneedle distances. Ninety-nine radiofrequency ablations were performed in six greyhounds using three different intramural electrode lengths (1 mm, 2.5 mm, and 5.5 mm). Lesions were created at 70 degrees C, 80 degrees C, and 90 degrees C for 60 seconds. All lesions were measured after staining with Gomori Trichrome. Lesion dimensions increased in a highly predictable manner with increasing electrode temperature or length. There was no popping or charring, even with target electrode temperature of 100 degrees C. There was significant correlation between intramural temperature 4 mm from the ablating electrode and lesion width (P < 0.001, R2= 0.45) and depth (P = 0.02, R2= 0.08). Feedback control of electrode temperature enables reliable intramural radiofrequency ablation without impedance rise even with target electrode temperature of 100 degrees C. Increasing the length of the intramural ablating electrode to > or = 5.5 mm and increasing temperatures to 90 degrees C-100 degrees C creates the largest lesions.
Collapse
Affiliation(s)
- Pramesh Kovoor
- Department of Cardiology, Westmead Hospital, Sydney, NSW, Austalia.
| | | | | | | | | | | | | |
Collapse
|
3
|
d'Avila A, Splinter R, Svenson RH, Scanavacca M, Pruitt E, Kasell J, Sosa E. New perspectives on catheter-based ablation of ventricular tachycardia complicating Chagas' disease: experimental evidence of the efficacy of near infrared lasers for catheter ablation of Chagas' VT. J Interv Card Electrophysiol 2002; 7:23-38. [PMID: 12391418 DOI: 10.1023/a:1020811915133] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Chronic Chagas' myocarditis can alter the myocardial substrate in a way that facilitates the emergence of fatal VT in a way similar to the long-term consequences of myocardial infarction. Post-myocardial infarction and Chagas' VT share many similarities: they are both macroreentrant circuits, entrainable, involving any wall segment from the endocardium to the epicardium. However, as compared to patients with post-MI VT, Chagasic patients tend to be younger and have a higher left ventricular ejection fraction. It is assumed, therefore, that their prognosis is closely related to VT treatment rather than the progression of the myocardial damage caused by the disease itself. Although sudden death is a rare event in patients in NYHA functional class I and II treated with amiodarone, VT recurrence rate is 30% a year. Drug therapy is ineffective for patients with advanced heart failure (100% recurrence rate/40% mortality in 1 year). Open-chest surgery is effective but requires very specialized centers and great expertise making its widespread use unrealistic. The results of combining RF endo/epicardial catheter ablation are still disappointing. Thus, research protocols on the search for new ablation technologies may greatly impact overall mortality in this subset of patients. This review will focus on the limitations of the current catheter-based ablation technology and suggest that an alternative approach is urgently needed. Experimental evidence of the efficacy of near infrared Lasers for catheter ablation will be reported along with investigations of the optical properties of the chagasic myocardium in the near infrared region to indicate that it might be not only feasible but also an appropriate choice to treat these patients.
Collapse
MESH Headings
- Animals
- Catheter Ablation/instrumentation
- Catheter Ablation/methods
- Chagas Cardiomyopathy/complications
- Death, Sudden, Cardiac/etiology
- Death, Sudden, Cardiac/prevention & control
- Disease Models, Animal
- Dogs
- Electrocardiography
- Electrophysiologic Techniques, Cardiac/instrumentation
- Electrophysiologic Techniques, Cardiac/methods
- Humans
- Infrared Rays/therapeutic use
- Laser Coagulation/instrumentation
- Laser Coagulation/methods
- Laser Therapy/instrumentation
- Laser Therapy/methods
- Myocardial Infarction/complications
- Stroke Volume
- Tachycardia, Ventricular/diagnosis
- Tachycardia, Ventricular/mortality
- Tachycardia, Ventricular/parasitology
- Tachycardia, Ventricular/surgery
Collapse
Affiliation(s)
- André d'Avila
- Unit of Cardiac Arrhythmia of the Heart Institute (InCor) of the University of São Paulo Medical School, Brazil
| | | | | | | | | | | | | |
Collapse
|
4
|
Thomas SP, Clout R, Deery C, Mohan AS, Ross DL. Microwave ablation of myocardial tissue: the effect of element design, tissue coupling, blood flow, power, and duration of exposure on lesion size. J Cardiovasc Electrophysiol 1999; 10:72-8. [PMID: 9930912 DOI: 10.1111/j.1540-8167.1999.tb00644.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
INTRODUCTION The biophysical properties of microwave electromagnetic radiation suggest that it may be an alternative to radiofrequency (RF) energy for ablation of arrhythmias resistant to treatment using RF ablation. METHODS AND RESULTS The aim of this study was to characterize lesions produced using simple element designs in a blood superfused ovine tissue model to simulate endocardial ablation. The effect of tissue bath flow, duration of microwave exposure, and changes in forward power on lesion size were examined using a modified monopole element. Lesion size increased with increasing duration of exposure and increasing forward power (P < 0.05). Lesion depth was 0.7+/-0.7 mm after 30 seconds and 11.5+/-1.9 mm after 360 seconds. Lesion depths at 61, 71, and 80 W were 6.4+/-3.7, 8.9+/-2.0, and 11.9+/-1.2 mm, respectively. Altering flow within the bath from 3 to 5 L/min did not significantly change lesion size. CONCLUSION Simple element designs can be used to produce a range of lesions from very small sizes to lesions that are transmural in the ventricle. The temperature half-time for microwave ablation is far greater than that of RF ablation. Like RF lesions, the lesions produced by microwave ablation have greater width than depth. Deep penetration of lesions into the ventricular myocardium can only be achieved with these elements by producing lesions of perhaps unnecessarily large volume.
Collapse
Affiliation(s)
- S P Thomas
- Department of Cardiology, Westmead Hospital, New South Wales, Australia
| | | | | | | | | |
Collapse
|
5
|
Sosa E, Scanavacca M, D'Avila A, Piccioni J, Sanchez O, Velarde JL, Silva M, Reolão B. Endocardial and epicardial ablation guided by nonsurgical transthoracic epicardial mapping to treat recurrent ventricular tachycardia. J Cardiovasc Electrophysiol 1998; 9:229-39. [PMID: 9580377 DOI: 10.1111/j.1540-8167.1998.tb00907.x] [Citation(s) in RCA: 223] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
INTRODUCTION An epicardial site of origin of ventricular tachycardia (VT) may explain unsuccessful endocardial radiofrequency (RF) catheter ablation. A new technique to map the epicardial surface of the heart through pericardial puncture was presented recently and opened the possibility of using epicardial mapping to guide endocardial ablation or epicardial catheter ablation. We report the efficacy and safety of these two approaches to treat 10 consecutive patients with VT and Chagas' disease. METHODS AND RESULTS Epicardial mapping was carried out with a regular steerable catheter introduced into the pericardial space. An epicardial circuit was found in 14 of 18 mapable VTs induced in 10 patients. Epicardial mapping was used to guide endocardial ablation in 4 patients and epicardial ablation in 6. The epicardial earliest activation site occurred 107+/-60 msec earlier than the onset of the QRS complex. At the epicardial site used to guide endocardial ablation, earliest activation occurred 75+/-55 msec before the QRS complex. Epicardial mid-diastolic potentials and/or continuous electrical activity were seen in 7 patients. After 4.8+/-2.9 seconds of epicardial RF applications, VT was rendered noninducible. Hemopericardium requiring drainage occurred in 1 patient; 3 others developed pericardial friction without hemopericardium. Patients remain asymptomatic 5 to 9 months after the procedure. Interruption during endocardial pulses occurred after 20.2+/-14 seconds (P = 0.004), but VT was always reinducible and the patients experienced a poor outcome. CONCLUSION Epicardial mapping does not enhance the effectiveness of endocardial pulses of RF. Epicardial applications of RF energy can safely and effectively treat patients with VT and Chagas' disease.
Collapse
Affiliation(s)
- E Sosa
- Heart Institute, University São Paulo Medical School, Brazil.
| | | | | | | | | | | | | | | |
Collapse
|
6
|
Hirao K, Yamamoto N, Toshida N, Nawata H, Ishihara N, Suzuki F, Miyasaka N, Hiejima K, Tanaka M. Transcatheter neodymium-yttrium-aluminum-garnet laser coagulation of canine ventricle using a balloon-tipped cardioscope. JAPANESE CIRCULATION JOURNAL 1997; 61:695-703. [PMID: 9276775 DOI: 10.1253/jcj.61.695] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The feasibility of transcatheter laser ablation of the canine left ventricle (LV) was tested using a newly developed cardioscope. In 17 anesthetized dogs, a combined laser-endoscope catheter, consisting of an endoscope encased in a 7-French flexible catheter with an inflatable and transparent balloon at the distal end, was introduced into the LV via the carotid artery. A 1064-nm neodymium-yttrium-aluminum-garnet (Nd:YAG) laser was delivered by laser optic fiber, which was introduced through the transport channel and positioned inside the saline-filled balloon. In 16 of 17 dogs, the endocardial surface of the LV was clearly observed. Laser energy totaling 500-5,000 J was applied sequentially in 13 dogs and laser irradiation was completed in all but 2 of the dogs. The excised hearts revealed well-demarcated oval-shaped lesions 2.5-9.5 mm deep in 7 of 11 dogs. Histologic sections revealed coagulation necrosis surrounded by a rim of contraction band necrosis. Thus, transballoon laser photocoagulation of the beating LV is feasible. The newly combined laser-endoscope catheter, which is still in its preliminary stages and needs to be improved to increase the success rate of photocoagulation, appears to be a promising alternative modality for catheter ablative therapy for ventricular tachycardia.
Collapse
Affiliation(s)
- K Hirao
- First Department of Internal Medicine, School of Medicine, Tokyo Medical and Dental University, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Panescu D. Intraventricular electrogram mapping and radiofrequency cardiac ablation for ventricular tachycardia. Physiol Meas 1997; 18:1-38. [PMID: 9046534 DOI: 10.1088/0967-3334/18/1/001] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Since its first use in the early 1980s, radiofrequency catheter ablation has gained acceptance as primary therapy for many cardiac rhythm disorders. This article reviews fundamentals of cardiac mapping and radiofrequency ablation and their clinical use for treatment of ventricular tachycardia. The review concludes that the use of radiofrequency ablation to cure ventricular tachycardia has consistently increased over the years, as better mapping and ablation tools have been made available to the medical community. Presently, high success and low complication rates are achieved only in patients with bundle branch, idiopathic, or monomorphic and stable ventricular tachycardias. The reviewed studies and reports suggest that, in order to increase the success rates in patients with ventricular tachycardias caused by coronary artery disease, mapping systems that can identify arrhythmogenic pathways more accurately and more efficiently and ablation devices capable of generating larger lesions are needed.
Collapse
Affiliation(s)
- D Panescu
- EP Technologies, Boston Scientific Company, Sunnyvale, CA 94086, USA
| |
Collapse
|
8
|
Abstract
The differential diagnosis of VTs with LBBB morphology includes several well-defined syndromes. Although the majority of cases are attributable to acquired structural heart disease, including ischemia, prior infarction, or dilated cardiomyopathy, consideration of specific right ventricular processes is essential to proper evaluation and treatment. The approach to older patients or those with evidence for heart disease should begin with an evaluation for coronary artery disease and an assessment of biventricular function. Careful evaluation for bundle branch reentry should be performed during electrophysiological study, especially when there is underlying conduction system disease. Younger patients, those without overt heart disease, or those with isolated right ventricular disease, should receive a complete noninvasive evaluation of right and left ventricular size and function. An abnormal SAECG or identification of intracardiac late potentials suggest right ventricular dysplasia or cardiomyopathy, whereas responsiveness to adenosine and absence of detectable heart disease support the diagnosis of idiopathic right VT. Newer techniques, including MRI, show promise in identifying subtle right ventricular disease not otherwise detectable even in the setting of presumed idiopathic right VT. Following surgical repair of selected congenital heart defects, particularly tetralogy of Fallot, symptoms of recurrent palpitations, near syncope, syncope, or aborted sudden death may be attributable to recurrent VT, and diagnostic electrophysiological study should be considered for these patients. Finally, SVTs with LBBB morphology, particularly cases associated with right-sided or septal accessory pathways, should always be considered in this differential diagnosis.
Collapse
Affiliation(s)
- C Nibley
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
| | | |
Collapse
|