REVIEW ARTICLES doi: http://dx.doi.org/10.18501/arrhythmia.2016.036 심방조동 이찬희 영남대학교의과대학내과학교실 Management of Atrial Flutter Chan-Hee Lee, MD Division of Cardiology, Yeungnam University Medical Center, Daegu, Republic of Korea Received: April 22, 2016 Accepted: October 5, 2016 Correspondence: Chan-Hee Lee, MD Division of Cardiology, Yeungnam University Medical Center, 170, Hyeonchung-ro, Nam-gu, Daegu 42415, Republic of Korea Tel: +82-53-620-3313 Fax: +82-53-621-3310 E-mail: chanheebox@naver.com Copyright 2016 The Official Journal of Korean Heart Rhythm Society Editorial Board & MMK Co., Ltd. ABSTRACT Atrial flutter is a macro-reentrant atrial arrhythmia characterized by regular atrial rate and constant P-wave morphology. The atrial flutter is divided into typical and atypical types, according to whether reentrant circuit involves the cavotricuspid isthmus. This review summarizes the management of atrial flutter based on 2015 ACC/ AHA/HRS guideline. Key Words: Atrial Flutter Cavotricuspid Isthmus Catheter Ablation 서론 심방조동이라고부르고, 드물지만시계방향의회귀회로를 심방조동은대회귀성 (macro-reentrant) 심방빈맥의가장흔한형태로서하대정맥-삼첨판협부 (cavotricuspid isthmus, CTI) 의존여부에따라서전형적 (typical, CTI dependent), 비전형적 (atypical, nonisthmus dependent) 심방조동으로나뉜다. 1 협부의존성심방조동 협부의존성심방조동 (CTI dependent atrial flutter) 은우심방에서형성된회귀성율동으로좌전사위 (left anterior oblique [LAO] view) 를기준으로삼첨판륜을따라반시계방향의회귀회로 (reentrant circuit) 를형성할때 (up the septum and down the free wall) 전형적 (typical) 형성할때역전형적 (reverse typical) 심방조동이라부른다. 2 심방조동은심방세동과유사한임상상황에서일어나는경우가많으며, 한환자가심방세동과심방조동을함께가지고있는경우가흔하다. CTI 전극도자절제술시행후 14-30개월의추적관찰기간동안 22-50% 의환자에서심방세동이발생한다고보고되고있다. 심방조동의전극도자절제술이후심방세동이발생할수있는위험인자로는기존의심방세동, 좌심실기능저하, 구조적또는허혈성심질환, 유도성 (inducible) 심방세동, 좌심방크기증가가있다. 3 심방세동에서항부정맥제 (flecainide, propafenone, amiodarone) 를사용하는경우에도심방조동이생길수있으며, 이경우반복적인조동을막기위해서협부의존성심방조동을도자절제하는것이필요하다. 4 또한, 심방조동 214
환자는심방세동과동일한혈색전위험도를가지는것으로여겨져심방세동과동일한정도의항응고치료가필요하다. 1 협부비의존성심방조동 협부비의존성심방조동 (nonisthmus dependent atrial flutter) 은협부를통한전도와관계없이발생하는대회귀성빈맥이며, 비전형적심방조동으로도불린다. 협부비의존성심방조동은심장수술이나심방세동의도자절제술이후의심방반흔형성 (atrial scarring), 특발성으로형성된심방일부의섬유화혹은해부학적이거나기능적인전도장애물에의해발생한다. 5,6 대표적으로좌측폐정맥부위도자절제술후좌측하부폐정맥과승모판륜사이에느린전도로가형성되어승모판륜을따라회귀하는 perimitral flutter과좌측과우측폐정맥선형절제후그사이의협곡을통해좌심방의지붕 (roof) 을따라회귀하는 roof dependent flutter가흔히발생한다. 심방세동도자절제술이후약 5% 에서소회귀성 (micro-reentrant) 또는대회귀성 (macro-reentrant) 좌심방빈맥이발생한다. 7 폐정맥고립 (pulmonary vein isolation) 만시행한경우이런부정맥은드물지만, 심방세동의유병기간이길수록, 좌심방이클수록, 선형절제를한경우일수록더흔하게발견된다. 8 협부의존성심방조동에비해협부비의존성심방조동의 도자절제술은좀더광범위한매핑 (mapping) 이필요하며, 성공률또한낮다. 회귀로의위치에따라도자절제술의접근법과위험도가달라진다. 또한, 국소성심방빈맥 (focal atrial tachycardia) 뿐만아니라단일고리 (loop) 또는이중고리회귀회로가존재할수도있다. 따라서매핑과도자절제술전에과거심방절개및도자절제술에대한기록을확인하는것이도움이된다. 모든형태의심방조동에서와같이심방세동의도자절제술후발생한협부비의존성조동은절제술이전의심방세동보다심박동수를조절하기가더욱어렵다. 심박동수조절을위한통상적인투약에도심박동수조절이안되면약물이나전기적심율동전환을이용한동리듬으로의전환이필요할수도있다. 하지만도자절제술이나심장수술후첫 3개월동안에는심방조동이흔히발견되기때문에심방조동에대한도자절제술은 3개월이후에고려하는것이좋다. 9 심방조동의급성기치료 2015 년 ACC/AHA/HRS (American College of Cardiology/ American Heart Association/Heart Rhythm Society) 급성기치료권고지침은 Figure 1과같다. 10 1. Class of recommendation I Hemodynamically stable Yes No Treatment strategy Treatment strategy Rhythm control Rate control Rhythm control Rate control Synchronized cardioversion, oral dofetilide, IV ibutilide, and/or rapid atrial pacing IV β-blockers, IV diltiazem, or IV verapamil IV amiodarone (ClassⅡa) Synchronized cardioversion IV amiodarone (ClassⅡa) Figure 1. Acute treatment of atrial flutter. IV, intravenous. 215
Atrial Flutter 1) 경구 dofetilide 또는 ibutilide 정주는심방조동의급성기약물학적심율동전환에유용하다 (Level of Evidence A). 약물을통한심율동전환은일반적으로동기화된전기적심율동전환에비해효과적이지못하고부정맥발생의위험성이있으나, 진정치료가불가능한경우나환자가원하는경우에선택사항이될수있다. 2) 정주또는경구베타차단제, diltiazem, verapamil 은혈역학적으로안정된경우급성기심박동수조절에유용하다 (B-R). 칼슘차단제정주요법중에서는안전성과효과면에서 diltiazem 이더좋다. Verapamil, diltiazem 은심장차단이나동기능부전이있는진행성심부전환자나조기흥분 (preexcitation) 환자에게사용해서는안된다. 베타차단제의심박동수저하효과는교감신경계활성을줄이는것과관련이있다. Esmolol이효과가빨라서일반적으로선호된다. 베타차단제는비대상성심부전이나반응성기도질환환자에서사용해서는안된다. 3) 계획적 (elective) 동기화전기적심율동전환술은안정된심방조동환자에서리듬조절을하고자할때선택한다 (B-NR). 심방세동과동일한정도의항응고요법이필요하다. 동리듬으로회복이되면빈맥매개성심근병증 (tachycardia mediated cardiomyopathy) 으로의진행을막을수있다. 4) 혈역학적으로불안정한경우나약물치료에반응이없는경우동기화된전기적심율동전환술이필요하다 (B-NR). 5) 빠른심방조율 (rapid atrial pacing) 을통한급성기심율동전환은영구형심박동기나제세동기를가지고있는경우나심장수술이후일시적심방조율을하는경우에유용하다 (C-LD). 빠른심방조율을통해서심방세동이유발된경우에심박동수조절이더욱잘되며, 순차적으로동리듬으로바뀔수도있다. 6) 심방세동과동일한정도의급성기항혈전치료가권고된다 (B-NR). 메타분석에서심방조동의심율동전환이후단기간뇌졸중발생률은 0-7% 였으며, 지속적인심방조동을가진환자의혈색전증발생률은연간평균 3% 였다. 2. Class of recommendation IIa 1) Amiodarone 정주요법은수축기심부전이있는심방조동환자의급성기심실박동조절 ( 심실조기흥분이없는경우 ) 에유용할수있다 (B-R). 심방조동의유지치료 2015년 ACC/AHA/HRS 유지치료권고지침은 Figure 2와같다. 10 1. Class of recommendation I 1) 증상이있거나약물치료에반응이없는환자에서 CTI 도자절제술이권고된다 (B-R). 삼첨판륜과하대정맥사이의절제선이회귀회로차단에효과적이기때문에 CTI가도자절제의목표가된다. 2) 혈역학적으로안정된경우베타차단제, diltiazem, verapamil이심박동수조절에유용하다 (C-LD). 일반적으로심부전이있는환자에서베타차단제가선호된다. 심실박동수가빨라지면서심실세동으로변성 (degeneration) 될수있기때문에조기흥분성심방조동에서는베타차단제, diltiazem, verapamil을투여해서는안된다. 3) 적어도 1종의항부정맥제를사용한이후에도증상이있는재발성협부비의존성심방조동에서도자절제술은유용하다. 이전수술이나도자절제술의접근법에대한정보와빈맥에대한세밀화된활성 (activation) 및동조화 (entrainment) 매핑이유용하다. 4) 심방세동과동일한수준의항혈전유지치료가권고된다. 216
Atrial flutter Treatment strategy Rate control Rhythm control Options to consider β-blockers, diltiazem, or verapamil Catheter ablation Amiodarone, dofetilide, or sotalol (ClassⅡa) Flecainide or propafenone (in the absence of SHD) (ClassⅡb) If ineffective Figure 2. Ongoing treatment of atrial flutter. SHD, structural heart disease (inducing ischemic heart disease). 2. Class of recommendation IIa 1) 증상이있는재발성심방조동에서동성리듬을유지하기위해다음과같은약물이유용할수있으며, 이는기존의심질환과동반질환에따라서선택해야한다 (B-R). (1) Amidorone 명확한독성때문에다른치료가금기이거나효과가없을때만사용한다. (2) Defetilide QT 간격과신기능변화에대한주의깊은관찰이필요하다. (3) Sotalol Class III 항부정맥제로피로나서맥과같은베타차단제의부작용과관련있다. 2) 심방세동에서 flecainide, propafenone, amiodarone 사용후발생한협부의존성심방조동에서도자절제술은합당하다 (B-NR). 3) 임상적또는유도성협부의존성심방조동의병력이있는환자에서심방세동전극도자절제술시 CTI를함께절제하는것은합당하다 (C-LD). 4) 치료선택에대한잠재적위험도및이득을고려한후증상이있는재발성협부비의존성심방조동에서항부정맥제를사용하기전첫번째치료로도자절제술이합당하다 (C-LD). 3. Class of recommendation IIb 1) 증상이있는재발성심방조동에서구조적또는허혈성심질환이없다면동리듬유지하는데 flecainide 또는 propafenone을고려해볼수있다 (B-R). 심방의전도속도가늦어져심방박동수는늦어지지만, 1:1 방실전도가되면서심실박동수가오히려증가할위험성이있다. 따라서방실전도를느리게하는베타차단제와 verapamil, diltiazem과같은칼슘차단제를병용해야한다. 2) 증상이없는재발성심방조동에서도자절제술은합당할수있다 (C-LD). 심방조동에서도자절제술은매우유용하며, 한번의시술로도성공률이 90% 이상이다. 약물치료보다동리듬을오래유지하는데더욱효과적이며, 빈맥매개심근병증의잠재적위험을피할수있다. 217
Atrial Flutter 결론 본종설을통해심방조동에대한 2015년 ACC/AHA/HRS 권고치침을정리해보았다. 심방조동환자를접할때항상심방세동을함께가지고있을가능성을염두에두며, 심방세동과동일한정도의항혈전치료가필요함을잊지말아야한다. References 1) January CT, Wann LS, Alpert JS, Calkins H, Cigarroa JE, Cleveland JC Jr., Conti JB, Ellinor PT, Ezekowitz MD, Field ME, Murray KT, Sacco RL, Stevenson WG, Tchou PJ, Tracy CM, Yancy CW, American College of Cardiology/American Heart Association Task Force on Practice G. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association task force on practice guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2014;64:e1-e76. 2) Saoudi N, Cosio F, Waldo A, Chen SA, Iesaka Y, Lesh M, Saksena S, Salerno J, Schoels W; Working Group of Arrhythmias of the European of C, the North American Society of P, Electrophysiology. A classification of atrial flutter and regular atrial tachycardia according to electrophysiological mechanisms and anatomical bases; a statement from a Joint Expert Group from the Working Group of arrhythmias of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology. Eur Heart J. 2001;22:1162-1182. 3) Ellis K, Wazni O, Marrouche N, Martin D, Gillinov M, McCarthy P, Saad EB, Bhargava M, Schweikert R, Saliba W, Bash D, Rossillo A, Erciyes D, Tchou P, Natale A. Incidence of atrial fibrillation postcavotricuspid isthmus ablation in patients with typical atrial flutter: left-atrial size as an independent predictor of atrial fibrillation recurrence. J Cardiovasc Electrophysiol. 2007;18:799-802. 4) Bertaglia E, Bonso A, Zoppo F, Proclemer A, Verlato R, Coro L, Mantovan R, Themistoclakis S, Raviele A, Pascotto P, North- Eastern Italian Study on Atrial Flutter Ablation I. Different clinical courses and predictors of atrial fibrillation occurrence after transisthmic ablation in patients with preablation lone atrial flutter, coexistent atrial fibrillation, and drug induced atrial flutter. Pacing Clin Electrophysiol. 2004;27:1507-1512. 5) Baker BM, Lindsay BD, Bromberg BI, Frazier DW, Cain ME, Smith JM. Catheter ablation of clinical intraatrial reentrant tachycardias resulting from previous atrial surgery: localizing and transecting the critical isthmus. J Am Coll Cardiol. 1996;28:411-417. 6) Jais P, Shah DC, Haissaguerre M, Hocini M, Peng JT, Takahashi A, Garrigue S, Le Metayer P, Clementy J. Mapping and ablation of left atrial flutters. Circulation. 2000;101:2928-2934. 7) Chugh A, Oral H, Lemola K, Hall B, Cheung P, Good E, Tamirisa K, Han J, Bogun F, Pelosi F, Jr., Morady F. Prevalence, mechanisms, and clinical significance of macroreentrant atrial tachycardia during and following left atrial ablation for atrial fibrillation. Heart Rhythm. 2005;2:464-471. 8) Veenhuyzen GD, Knecht S, O'Neill MD, Phil D, Wright M, Nault I, Weerasooriya R, Miyazaki S, Sacher F, Hocini M, Jais P, Haissaguerre M. Atrial tachycardias encountered during and after catheter ablation for atrial fibrillation: part I: classification, incidence, management. Pacing Clin Electrophysiol. 2009;32:393-398. 9) Calkins H, Kuck KH, Cappato R, Brugada J, Camm AJ, Chen SA, Crijns HJ, Damiano RJ, Jr., Davies DW, DiMarco J, Edgerton J, Ellenbogen K, Ezekowitz MD, Haines DE, Haissaguerre M, Hindricks G, Iesaka Y, Jackman W, Jalife J, Jais P, Kalman J, Keane D, Kim YH, Kirchhof P, Klein G, Kottkamp H, Kumagai K, Lindsay BD, Mansour M, Marchlinski FE, McCarthy PM, Mont JL, Morady F, Nademanee K, Nakagawa H, Natale A, Nattel S, Packer DL, Pappone C, Prystowsky E, Raviele A, Reddy V, Ruskin JN, Shemin RJ, Tsao HM, Wilber D, Heart Rhythm Society Task Force on C, Surgical Ablation of Atrial F. 2012 HRS/EHRA/ ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design: a report of the Heart Rhythm Society (HRS) task force on catheter and surgical ablation of atrial fibrillation. Developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology (ESC) and the European Cardiac Arrhythmia Society (ECAS); and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). Endorsed by the governing bodies of the American College of Cardiology Foundation, the American Heart Association, the European 218
Cardiac Arrhythmia Society, the European Heart Rhythm Association, the Society of Thoracic Surgeons, the Asia Pacific Heart Rhythm Society, and the Heart Rhythm Society. Heart Rhythm. 2012;9:632-696.e621. 10) Page RL, Joglar JA, Caldwell MA, Calkins H, Conti JB, Deal BJ, Estes NA, 3rd, Field ME, Goldberger ZD, Hammill SC, Indik JH, Lindsay BD, Olshansky B, Russo AM, Shen WK, Tracy CM, Al-Khatib SM. 2015 ACC/AHA/HRS guideline for the management of adult patients with supraventricular tachycardia: a report of the American College of Cardiology/American Heart Association task force on clinical practice guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2016;67:e27-e115. 219