MORPHOLOGICAL ASSESSMENT OF RADIO-FREQUENCY ABLATION LINES OF THE MYOCARDIUM OF THE LEFT ATRIAL APPENDAGE IN PATIENTS WITH ATRIAL FIBRILLATION
Abstract
The using in clinical practice of devices for radiofrequency ablation of the atrial myocardium significantly reduced the trauma of the operation and reduced the time of its execution. At the same time, radiofrequency ablation does not violate the integrity of the atrial walls, and the isolation effect is achieved only due to structural damage to the myocardium. The study was carried out on biopsies of the left atrial appendages, resected in patients (n=18) suffering from ischemic heart disease and non-paroxysmal atrial fibrillation. The histological structure of ablation lines formed on the myocardium by two different radiofrequency devices was studied. Bioptats of the left atrial appendages were fixed in a 10% buffered formalin solution, then their fragments were performed in a Microm STP120 histoprocessor, which were embedded in Histo-mix paraffin using the Tissue TekR Tek 5 modular system. Paraffin sections 3–5 µm thick were stained using routine histological methods and embedded in Bio Mount medium. Microscopic examination of the preparations and their photographic recording were carried out on a hardware-software complex Nic-Elements AR 4.12.00 on the basis of a research microscope Nicon 50S with a digital camera Nicon DS-Fi. The formation of ablation lines was carried out by: 1) applying one radio frequency exposure; 2) three radio frequency exposures; 3) application of radiofrequency exposure to a persistent reduction in the time to achieve transmurality. The histological study of the results of exposure to the myocardium of the left ears of the heart was carried out in a double-blind manner. The envelope, which contained data on the method of formation of ablation lines, was opened after receiving the results of the histological examination. As a result of the study, it was found that the priority criterion for the usefulness of the formed ablation lines under radiofrequency exposure to the left atrium in patients with non-valvular fibrillation should be recognized as a persistent decrease in the time to achieve transmurality. Based on this criterion, it is possible to obtain ablation lines with a complete absence of viable cardiomyocytes in their zone.
About the Authors
Sergei A. Vachev
Federal Scientific Clinical Center for specialized medical care and medical technology, Moscow
Russian Federation
Competing Interests:
Russian Federation
Candidate of Medical Sciences, cardiovascular surgeon of the Department of Cardiac Surgery
Competing Interests:
The author declares that he did not have any conflicts of interest in the planning, implementation, financing and use of the results of this study
Feodor G. Zabozlajev
Federal Scientific Clinical Center for specialized medical care and medical technology, Moscow
Russian Federation
Competing Interests:
Russian Federation
Doctor of Medical Sciences, Head of the Department of Pathology
Competing Interests:
The author declares that he did not have any conflicts of interest in the planning, implementation, financing and use of the results of this study
Dinara R. Nizametdinova
Private Medical University REAVIZ, Samara
Russian Federation
Competing Interests:
Russian Federation
PhD Studentess og the Department of Morphology and Pathology
Competing Interests:
The author declares that he did not have any conflicts of interest in the planning, implementation, financing and use of the results of this study
References
1. Lawrance CP, Henn MC, Miller JR, Sinn LA, Schuessler RB, Damiano Rj Jr. Comparison of the stand-alone Cox-Maze IV procedure to the concomitant Cox-Maze IV and mitral valve procedure for atrial fibril-lation. Ann Cardiothorac Surg. 2014;3(1):55–61. DOI: 10.3978/j.issn.2225-319X.2013.12.09
2. Prasad SM, Maniar HS, Camillo CJ, Schuessler RB, Boineau JP, Sundt TM 3rd, Cox JL, Damiano Rj Jr. The Cox maze III procedure for atrial fibrillation: long-term efficacy in patients undergoing lone versus concomitant procedures. J Thoracic Cardiovasc Surg. 2003;126(6):1822-8. DOI: 10.1016/s0022-5223(03)01287-x.
3. Cox JL, Ad N, Palazzo T, Fitzpatrick S, Suyderhoud JP, De Groot KW, Pirovic EA, Lou HC, Duvall WZ, Kim YD. The Maze-III procedure combined with valve surgery. Semin Thoracic Cardiovasc Surg. 2000;12(1):53-5. DOI: 10.1016/s1043-0679(00)70017-7.
4. Gaynor SL, Diodato MD, Prasad SM, Ishii Y, Schuessler RB, Bailey MS, Damiano NR, Bloch JB, Moon MR, Damiano Rj Jr. A prospective, single-center clinical trial of a modified Cox maze procedure with bi-polar radiofrequency ablation. J Thoracic Cardiovasc Surg. 2004;128(4):535-42. DOI: 10.1016/j.jtcvs.2004.02.044.
5. John M, Rook A, Post A, Mersman A, Allen W, Schramm C, Razavi M. Bipolar ablation's unique para-digm: Duration and power as respectively distinct primary determinants of transmurality and steam pop formation. Heart Rhythm O2. 2020;1(4):290-296. DOI: 10.1016/j.hroo.2020.06.006.
6. Khiabani AJ, MacGregor RM, Manghelli JL, Ruaengsri C, Carter DI, Melby SJ, Schuessler RB, Damiano Rj Jr. Bipolar Radiofrequency Ablation on Explanted Human Hearts: How to Ensure Transmural Lesions. Ann Thorac Surg. 2020;110(6):1933-1939. DOI: 10.1016/j.athoracsur.2020.04.079.
7. Cabrera JA, Pizarro G, Sánchez-Quintana D. Transmural ablation of all the pulmonary veins: is it the Holy Grail for cure of atrial fibrillation? Eur Heart J. 2010;31(22):2708-11. DOI: 10.1093/eurheartj/ehq241.
8. Dickfeld T, Kato R, Zviman M, Lai S, Meininger G, Lardo AC, Roguin A, Blumke D, Berger R, Calkins H, Halperin H. Characterization of radiofrequency ablation lesions with gadolinium-enhanced cardiovas-cular magnetic resonance imaging. J Am Coll Cardiol. 2006;47(2):370-8. DOI: 10.1016/j.jacc.2005.07.070.
9. Deneke T, Khargi K, Müller KM, Lemke B, Mügge A, Laczkovics A, Becker AE, Grewe PH. Histopathol-ogy of intraoperatively induced linear radiofrequency ablation lesions in patients with chronic atrial fibril-lation. Eur Heart J. 2005;26(17):1797-803. DOI: 10.1093/eurheartj/ehi255.
10. Melby SJ, Schuessler RB, Damiano Rj Jr. Ablation technology for the surgical treatment of atrial fibrilla-tion. ASAIO J. 2013;59(5):461-8. DOI: 10.1097/MAT.0b013e3182a394f1.
11. Yang Y, Cheng J, Bochoeyer A, Hamdan MH, Kowal RC, Page R, Lee RJ, Steiner PR, Saxon LA, Lesh MD, Modin GW, Scheinman MM. Atypical right atrial flutter patterns. Circulation. 2001;103(25):3092-8. DOI: 10.1161/01.cir.103.25.3092.
12. Cosío FG, Martín-Peñato A, Pastor A, Nuñez A, Goicolea A. Atypical flutter: a review. Pacing Clin Electrophysiol. 2003;26(11):2157-69. DOI: 10.1046/j.1460-9592.2003.00336.x.
13. Coffey JO, d'Avila A, Dukkipati S, Danik SB, Gangireddy SR, Koruth JS, Miller MA, Sager SJ, Eggert CA, Reddy VY. Catheter ablation of scar-related atypical atrial flutter. Europace. 2013;15(3):414-9. DOI: 10.1093/europace/eus312.
14. Cosío FG. Atrial Flutter, Typical and Atypical: A Review. Arrhythm Electrophysiol Rev. 2017;6(2):55-62. DOI: 10.15420/aer.2017.5.2. PMID: 28835836.
15. Shivkumar K. Percutaneous epicardial ablation of atrial fibrillation. Heart Rhythm. 2008;5(1):152-4. DOI: 10.1016/j.hrthm.2007.08.033.
16. Damiano Rj Jr, Schwartz FH, Bailey MS, Maniar HS, Munfakh NA, Moon MR, Schuessler RB. The Cox maze IV procedure: predictors of late recurrence. J Thoracic Cardiovasc Surg. 2011;141(1):113-21. DOI: 10.1016/j.jtcvs.2010.08.067.
17. Doty JR, Doty DB, Jones KW, Flores JH, Mensah M, Reid BB, Clayson SE, Snow G, Righter E, Millar RC. Comparison of standard Maze III and radiofrequency Maze operations for treatment of atrial fibrilla-tion. J Thorac Cardiovasc Surg. 2007;133(4):1037-44. DOI: 10.1016/j.jtcvs.2006.12.001.
18. Sághy L, Tutuianu C, Szilágyi J. Atrial tachycardias following atrial fibrillation ablation. Curr Cardiol Rev. 2015;11(2):149-56. DOI: 10.2174/1573403x10666141013122400.
19. Schwartzman D, Ren JF, Devine WA, Callans DJ. Cardiac swelling associated with linear radiofrequency ablation in the atrium. J Interv Card Electrophysiol. 2001;5(2):159-66. DOI: 10.1023/a:1011477408021.
20. Dickfeld T, Kato R, Zviman M, Nazarian S, Dong J, Ashikaga H, Lardo AC, Berger RD, Calkins H, Halperin H. Characterization of acute and subacute radiofrequency ablation lesions with nonenhanced magnetic resonance imaging. Heart Rhythm. 2007;4(2):208-14. DOI: 10.1016/j.hrthm.2006.10.019.
21. Kowalski M, Grimes MM, Perez FJ, Kenigsberg DN, Koneru J, Kasirajan V, Wood MA, Ellenbogen KA. Histopathologic characterization of chronic radiofrequency ablation lesions for pulmonary vein isolation. J Am Coll Cardiol. 2012;59(10):930-8. DOI: 10.1016/j.jacc.2011.09.076.
22. Hamner CE, Lutterman A, Potter DD, Sundt TM 3rd, Schaff HV, Francischelli D. Irrigated bipolar ra-diofrequency ablation with transmurality feedback for the surgical Cox-Maze procedure. Heart Surg Fo-rum. 2003;6(5):418-23.
23. Lee AM, Aziz A, Clark KL, Schuessler RB, Damiano Rj Jr. Chronic performance of a novel radiofrequen-cy ablation device on the beating heart: Limitations of conduction delay to assess transmurality. J Thorac Cardiovasc Surg. 2012;144(4):859-65. DOI: 10.1016/j.jtcvs.2012.01.001.
24. Bugge E, Nicholson IA, Thomas SP. Comparison of bipolar and unipolar radiofrequency ablation in an in vivo experimental model. Eur J Cardiothorac Surg. 2005;28(1):76-80; discussion 80-2. DOI: 10.1016/j.ejcts.2005.02.028.
The priority criterion for the usefulness of the formed ablation lines during radiofrequency exposure to the left atrium in patients with nonvalvular fibrillation should be considered a persistent decrease in the time to achieve transmurality
Review
For citations:
Vachev S.A., Zabozlajev F.G., Nizametdinova D.R. MORPHOLOGICAL ASSESSMENT OF RADIO-FREQUENCY ABLATION LINES OF THE MYOCARDIUM OF THE LEFT ATRIAL APPENDAGE IN PATIENTS WITH ATRIAL FIBRILLATION. Morphological newsletter. 2021;29(2):74-79. (In Russ.)
Views:
288
