Cardiac Swelling Associated with Linear Radiofrequency Ablation in the Atrium
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Objectives: To characterize myocardial swelling in response to application of endocardial radio- frequency ablation lesions.
Background: In individual patients, we have observed that ablation in the posterior right atrium was associated with echocardiographic evidence of atrial and contiguous right pulmonary vein wall swelling.
Methods: 1. Human Subjects: “linear” ablation was performed in the posterior right atrium in 10 subjects; a portion of the ablation lesion was contiguous to the right pulmonary vein; this area was defined as the “contiguity zone”. In the contiguity zone, right atrial wall thickness and pulmonary vein lumen diameter were measured utilizing intracardiac echocardiography. Measurements were made just prior to (baseline) and immediately after ablation.
2. Porcine Subjects: linear ablation was performed in the posterior right atrium of 14 pigs. In the contiguity zone, atrial wall thickness, interstitial space thickness, right pulmonary vein wall thickness and lumen diameter were measured using intracardiac echocardiography. Measurements were made at baseline, immediately after ablation, and at 1, 4, 8 or 12 weeks after ablation (followup). Post-mortem pathologic evaluation of the contiguity zone was performed.
Results: 1. Human Subjects: Immediately after ablation, relative to baseline right atrial wall thickness was significantly increased (9.4±3.1[emsp4 ]mm versus 5.4±1.5[emsp4 ]mm) and right pulmonary vein lumen diameter was significantly decreased (6.2±2.9[emsp4 ]mm versus 8.1±2.9[emsp4 ]mm).
2. Porcine Subjects: Immediately after ablation, right atrial wall thickness (4.1±1.2[emsp4 ]mm), interstitial space thickness (1.9±1.1[emsp4 ]mm), and right pulmonary vein wall thickness (1.2±0.4[emsp4 ]mm) were each significantly increased relative to baseline (1.0±0.3[emsp4 ]mm, 0±0[emsp4 ]mm, and 0.7±0.2[emsp4 ]mm, respectively) and pulmonary vein lumen diameter was significantly decreased (5.0±1.4[emsp4 ]mm versus 6.9±2.2[emsp4 ]mm). Similar findings were made at the 1 week followup interval. At 4, 8 and 12 week followup intervals, thicknesses and lumen diameter were not significantly different from baseline. At post-mortem examination, direct measurements of wall thickness were significantly correlated with echocardiographic measurements. Histologic analysis demonstrated edema to be the cause of the early wall thickness and lumen diameter changes. Ablation lesions were transmural in the right atria of all animals; in some animals, lesion formation was also observed in the pulmonary vein wall.
Conclusions: Cardiac edema resulting from right atrial linear ablation results in swelling of atrial and contiguous right pulmonary vein walls, as well as the interposed extracardiac interstitial space. These changes are associated with a decrease in pulmonary vein lumen diameter. Swelling evolves rapidly and resolves within 4 weeks.
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- 1.Schwartzman D, Kuck K-H. Anatomy-guided linear atrial lesions for radiofrequency catheter ablation of atrial fibrillation. PACE1998;21:1959-1978.Google Scholar
- 2.Mitchell M, McRury I, Haines D. Linear atrial ablation in a canine model of chronic atrial fibrillation: Morphological and electrophysiologic observations. Circulation1998;1176-1185.Google Scholar
- 3.Ernst S, Ouyang F, Volkmer M, et al. Clinical followup after primary catheter ablation of atrial fibrillation using the CARTO system. Circulation1998;I-180.Google Scholar
- 4.Robbins IM, Colvin EV, Doyle TP, et al. Pulmonary vein stenosis after catheter ablation of atrial fibrillation. Circulation1998;98:1769-1775.Google Scholar
- 5.Kalman JM, Fitzpatrick AP, Olgin JE, et al. Biophysical characteristics of radiofrequency lesion formation in vivo: dynamics of catheter tip-tissue contact evaluated by intracardiac echocardiography. Am Heart J1997;133:8-18.Google Scholar
- 6.Callans DJ, Ren JF, Schwartzman D, Gottlieb CD, Chaudhry FA, Marchlinski FE. Narrowing of the superior vena cava-right atrium junction during radiofrequency catheter ablation for inappropriate sinus tachycardia: Analysis with intracardiac echocardiography. J Am Coll Cardiol1999;33(6):1667-1670.Google Scholar
- 7.Schwartzman D, Wackowski C, Scharfenberg C. Outcome of right atrial linear radiofrequency ablation for suppression of atrial fibrillation. PACE1999;22:904.Google Scholar
- 8.Ren J-F, Schwartzman D, Lighty GW, Jr., et al. Multiplane transesophageal and intracardiac echocardiography in large swine: Imaging technique, normal values, and research applications. Echocardiography1997;14(1):135-147.Google Scholar
- 9.Crick SJ, Sheppard MN, Ho SY, Gepstein L, Anderson RH. Anatomy of the pig heart: Comparisons with normal human cardiac structure. J Anat1998; 193:105-119.Google Scholar
- 10.Jensen DN, Wagner BK, Rose AG, Mehra R, Edwards JE. Human atrial dimensions relevant to intracardiac ablation “maze” procedures for atrial fibrillation. PACE1997;20:1146.Google Scholar
- 11.Schwartzman D, Michele JJ, Trankiem CT, Ren J-F, Gottipaty V, Anderson KP. Radiofrequency power titration for atrial ablation: Prospective comparison of thermometry versus electrogram amplitude reduction. PACE1998;21(4):849.Google Scholar
- 12.Ren J-F, Schwartzman D, Callans DJ, Gottlieb CD, Marchlinski FE, Chaudhry FA. Imaging technique and clinical utility for electrophysiologic procedures of lower frequency (9 MHz) intracardiac echocardiography. Am J Cardiol 1998;82:1557-1560.Google Scholar
- 13.Ren JF, Schwartzman D, Brode SE, Callans DJ, Chaudhry FA, Marchlinski FE. Right atrial mural swelling and its effect on adjacent great vessels from linear ablation for atrial fibrillation. J Am Coll Cardiol1999;33(2):137A.Google Scholar
- 14.Ren JF, Schwartzman D, Brode SE. Evolution of right pulmonary vein lumen narrowing after right atrial linear radiofrequency ablation. J Am Coll Cardiol1999;33(2):137A.Google Scholar
- 15.Schwartzman D, Fischer WD, Spencer EP, Pariszhkaya M, Devine W. Linear radiofrequency atrial lesions deployed using an irrigated electrode: Electrical and histologic evolution. Circulation1998;I-567.Google Scholar
- 16.Huang SKS, Bharati S, Lev M. Electrophysiologic and histologic observations of chronic atrioventricular block induced by closed-chest catheter dessication with radiofrequency energy. PACE1987;10:805-816.Google Scholar
- 17.Ruiz-Ros JA, Ortega VV, Martinez JA, et al. Stunned myocardium and cellular damage in patients undergoing valvular cardiac surgery and pretreated with captopril. J Cardiovasc Surg1999;40:203-210.Google Scholar
- 18.Melton SM, Davis KA, Moomey CB, Jr., Fabian TC, Proctor KG. Mediator-dependent secondary injury after unilateral blunt thoracic trauma. Shock1999;11:396-402.Google Scholar
- 19.Johnsson C, Hallgren R, Elvin A, Gerdin B, Tufveson G. Hyaluronidase ameliorates rejection-induced edema. Transpl Int1999;12:235-243.Google Scholar
- 20.Shaffer RF, Baumgarten CM, Damiano RJ, Jr. Prevention of cellular edema directly caused by hypothermic cardioplegia. J Thorac Cardiovasc Surg1998;115:1189-1195.Google Scholar
- 21.Mehlhorn U, Davis KL, Laine GA, Geissler HJ, Allen SJ. Myocardial fluid balance in hypertension. Microcirculation1996;3:371-378.Google Scholar
- 22.Yu P, Boughner DR, Sibbald WJ, Keys J, Dunmore J, Martin CM. Myocardial collagen changes and edema in rats with hyperdynamic sepsis. Crit Care Med1997;25:657-662.Google Scholar
- 23.Sorota S, Du XY. Delayed activation of cardiac-swelling induced chloride current after step changes in cell size. J Cardiovasc Electrophysiol1998;9:825-831.Google Scholar
- 24.Vandenberg JI, Bett GC, Powell T. Contribution of a swelling-activated chloride current to changes in the cardiac action potential. Am J Physiol1997;273:C541-C547.Google Scholar
- 25.Du XY, Sorota S. Cardiac swelling-induced chloride current depolarizes canine atrial myocytes. Am J Physiol1997;272:H1904-H1916.Google Scholar
- 26.Lei M, Kohl P. Swelling-induced decrease in spontaneous pacemaker activity of rabbit isolated sino-atrial node cells. Acta Physiol Scand1998;164:1-12.Google Scholar
- 27.Olgin JE, Strickberger SA, Lesh M, et al. Right atrial ablation of lone atrial fibrillation with multielectrode coil catheters. PACE1999;22:904.Google Scholar