J Neurocrit Care 2014;7(1):25-32 본 론 심실성부정맥 (ventricular tachyarrhythmias) 개요 중환자실감시심전도 (ECG monitoring) 에서넓은폭의 QRS 파를보이는빈맥 (wide QRS tachycardia, WQR

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1 REVIEW J Neurocrit Care 2014;7(1):25-32 ISSN 중환자실에서흔한부정맥의진료 서울아산병원심장병원, 울산대학교의과대학내과학교실 남기병 Cardiac Arrhythmias in the Intensive Care Units Gi-Byoung Nam, MD Heart Institute, Asan Medical Center, Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, Korea Background: Cardiac arrhythmias in critically ill patients often cause severe hemodynamic impairment or medical complications, precipitating rapid deterioration of patients conditions. This manuscript describes common or fatal cardiac arrhythmias occurring in patients hospitalized at intensive care units. Results: Differential diagnosis of wide QRS tachycardias includes ventricular tachycardias (VTs), supraventricular tachycardias with aberrant conduction and noise artifacts. Idiopathic VTs in patients with structurally normal hearts are responsive to antiarrhythmic agents and are cured by catheter ablation. Ventricular tachycardias in structural heart diseases require amiodarone for acute suppression and implantable defibrillator for longterm management. Polymorphic VTs or Torsades de Pointes are effectively suppressed by intravenous infusion of magnesium. Discontinuation of offending agents and, in some refractory cases, installation of temporary pacing is necessary. Atrial fibrillation (AF) is the most commonly observed tachyarrhythmias in intensive care settings. When combined with sepsis or congestive heart failure, AF with rapid ventricular response induces hypotension and sympathetic stimulation, which again aggravates rapid ventricular responses. This viscious cycle continues until adequate rate control measures are initiated. Intravenous amiodarone and anticoagulation are important initial management. In rare cases, electrical noises mimic ventricular tachycardias. Noises are distinguished from true VTs by identification of sharp QRS notches and stable hemodynamics during the events. Conclusion: Proper interpretation of monitoring or standard ECG is crucial for differential diagnosis of cardiac arrhythmias occurring in intensive care units. Management should be tailored based upon arrhythmia characteristics and individual medical conditions. J Neurocrit Care 2014;7(1):25-32 Key Words: Tachycardia; Bradycardia; Intensive care 서 론 중환자실환자에서나타나는부정맥은기저심질환혹은내 과적인전신질환이있는상황에서나타나는경우가많고, 부 정맥이발생하면심한혈역학적변화가나타나서임상경과를 급격히악화시키는원인이될수있으므로중환자실에서부정 맥진료는중요한의미를갖는다. Figure 1 의도표는 Received: November 13, 2013 / Revised: December 8, 2013 Accepted: December 9, 2013 Address for correspondence: Gi-Byoung Nam, MD Heart Institute, Asan Medical Center, Department of Internal Medicine, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpagu, Seoul , Korea Fax: , Tel: gbnam@amc.seoul.kr 부터 까지 3개월간서울아산병원내, 외과계, 그리고신경 / 심장계중환자실환자에서발생한부정맥의빈도를표로정리한것이며중환자실환자에서다양한부정맥이관찰되는것을보여주고있다. 가장흔하게나타나는부정맥은심방세동이며심실빈맥은치명적이기는하지만비교적드물게나타난다. 신경계중환자실에서는중추신경계손상후나타나는 neurogenic stunned myocardium 과관련되어심부전이나타나거나심장의재분극이연장되고 (QT prolongation) 다형심실빈맥을포함한다양한부정맥을유발하기도한다. 본고에서는중환자실에서흔하게관찰되는 Torsades de Pointes (TdP) 형태의다형심실빈맥과심방세동의치료에대하여주로기술하고말미에는서맥을보이는환자에서의중환자실에서필요한진료를간략히추가하겠다. Copyright 2014 The Korean Neurocritical Care Society 25

J Neurocrit Care 2014;7(1):25-32 본 론 심실성부정맥 (ventricular tachyarrhythmias) 개요 중환자실감시심전도 (ECG monitoring) 에서넓은폭의 QRS 파를보이는빈맥 (wide QRS tachycardia, WQRST) 이나타나면 다양한감별진단이필요하며크게는심실빈맥과심실상빈맥

Cardiac arrhythmias observed in patients admitted at intensive care units of Asan Medical Center are shown.

2 J Neurocrit Care 2014;7(1):25-32 본 론 심실성부정맥 (ventricular tachyarrhythmias) 개요 중환자실감시심전도 (ECG monitoring) 에서넓은폭의 QRS 파를보이는빈맥 (wide QRS tachycardia, WQRST) 이나타나면 다양한감별진단이필요하며크게는심실빈맥과심실상빈맥 의편위전도를감별하는것이중요하다. 심전도파형에서방 실해리현상 (Fig. 2), 흉부유도전체에서 QRS 파가음성혹은양 Figure 1. Prevalence of cardiac arrhythmias in the intensive care units. Cardiac arrhythmias observed in patients admitted at intensive care units of Asan Medical Center are shown. Numbers in the parentheses denote the number of arrhythmias that occurred during the period between to Abbreviations are as follows. AF: atrial fibrillation, AFL; atrial flutter, PSVT: paroxysmal supraventricular tachycardia, NSVT: nonsustained ventricular tachycardia, mvt: monomorphic ventricular tachycardia, pvt: polymorphic ventricular tachycardia, VF: ventricular fibrillation, C-AVB: complete atrioventricular block, 2-AVB: second degree atrioventricular block. 성을보이는 precordial concordance 소견이관찰되면심실빈맥을강력하게시사하므로쉽게감별이가능하나이러한소견이없으면 QRS파의형태를보고감별하여야하며경험이필요하다. 응급실이나중환자실에서 QRS파폭이넓고규칙적인빈맥의감별진단목적으로아데노신을주사할수는있으나이는간혹관상동맥병환자에서심실세동을일으킬수있고 Wolff- Parkinson-White 증후군환자에서는심방세동을유발할수있으므로심전도에서이러한소견이보이는환자에서는아데노신사용에주의를요하여야한다. 1 일반적으로단형심실빈맥이관찰되면기저심질환이없었던환자에서는특발성심실빈맥의가능성이많은데, 특징적으로좌각차단, 우축편위를보이거나우각차단, 좌축편위의심전도특성으로보이면더욱확실하게심실빈맥을진단할수있다 (Fig. 2). 이러한특발성심실빈맥은대부분약물치료에잘반응하고장기적인예후도양호하므로그임상적경과가양호하다. 하지만심근경색, 심근병증 ( 비후성, 확장성 ) 등의심질환이있는환자에서나타나는 wide QRS tachycardia 는그약물치료도복잡하고장기적인치료전략이다양하게달라지므로 ( 약물치료, 도자절제술, 제세동기, 심장이식등 ) 부정맥전문의와치료방향을논의하는것이좋다. 다형심실빈맥은전해질장애, 심근허혈등의원인으로도나타날수있으나그보다더흔하게는약물 (QT간격을연장시키는약물 ), 전해질이상, 일시적으로나타난스트레스성심근병증 (stress cardiomyopathy, SCM), neurogenic stunned myocardium 등과관련하여나타나는 TdP 가더임상적으로중요하다. 이러한 TdP 은대 Figure 2. Monomorphic ventricular tachycardia in a patient with structurally normal heart. A 12 year-old girl was admitted at the cardiac intensive care unit for the evaluation of recurrent palpitation and syncope. A 12-lead ECG taken during palpitation revealed a wide QRS tachycardia with right bundle branch block and left axis deviation. Small indentations (arrows) in the limb lead III suggest ventriculoatrial dissociation, a marker of ventricular tachycardia. The absence of structural heart disease and ECG morphologic characteristics (right bundle branch block and left axis) of VT confirmed the diagnosis of idiopathic fascicular tachycardia. Tachycardia was terminated by intravenous infusion of verapamil. 26

Cardiac Arrhythmias in the Intensive Care Units Nam GB Figure 3. Polymorphic ventricular tachycardia with QT prolongation in a patient hospitalized for subarachnoid hemorrhage.

3 Cardiac Arrhythmias in the Intensive Care Units Nam GB Figure 3. Polymorphic ventricular tachycardia with QT prolongation in a patient hospitalized for subarachnoid hemorrhage. A 57 year-old female patient was referred for the management of subarachnoid hemorrhage. A marked prolongation of QT interval and polymorphic ventricular tachycardia is noted. Tachycardia was initiated after a pause following premature ventricular beat (star) in a short-long-short sequence of activation. A giant T wave precedes ventricular tachycardia (arrow). Tachycardia was completely suppressed by intravenous infusion of magnesium (2.0 gram). Quinolone antibiotics and quetiapine were discontinued because of the potential for prolongation of QT intervals. 부분심전도상저명한 QT간격의연장소견이관찰되고, 특히빈맥의시작직전에잦은조기심실수축 (premature ventricular contraction, PVC) 과 giant T wave 와같이현저하게큰 T파가나타나면서빈맥이시작되는것이특징적이다 (Fig. 3). 일단빈맥이시작되면연속적으로되풀이되어나타나서 ( 반복적으로심실빈맥이나타나는것을 electrical storm이라고함 ) 혈역학적허탈 (collapse) 이동반되므로중환자실환자진료시상당히당혹스럽게느껴지고적절한치료가제대로이루어지지않아서반복적인전기충격만지속하다가환자가사망에이를수도있다. 반면, 치료가이드라인에따라적절한치료를시작하면약물에대한반응이좋고단시간내에뚜렷하게부정맥의호전을볼수있으므로 TdP 에대한적절한인지와치료에대한지식이무엇보다도중요한부정맥이다. 2 단형심실빈맥의치료기저심질환이없는환자에서는약물치료가효과적이며, 특히우각차단, 좌축편위를보이는특발성좌심실빈맥은 verapamil에잘들어서일명 verapamil-sensitive ventricular tachycardia로도불리운다. 좌각차단, 우축편위를보이는우심실유출로빈맥은일반적으로다양한항부정맥제 (beta-blocker, Caantagonist, propafenone, flecainide, pilsicainide, sotalol, amiodarone) 에잘반응하므로약물치료가수월하다. 반면심질환이있는환자에서나타나는단형심실빈맥은사용할수있는약 물이아미오다론에국한되고일부허혈성심질환환자에서는리도카인을써볼수있는정도이므로약물치료에서그선택의폭이넓지않다. 일반적으로리도카인은그작용효과가빨라서심실종료효과를수분내에기대할수있으나실제적으로부정맥종료의효과는아미오다론에비하여약한편이다. 아미오다론은그효과는리도케인에비하여뛰어나나주사약을쓰더라도그효과가상당히느리게나타나고 ( 적어도수시간, 보통수일 ), 간장애, 심한서맥이나저혈압등의부작용이드물지만심하게나타날수있어그사용에주의를요한다 (Table 1). 부작용의발생은아미오다론을주사제로사용할경우첫주에는 1-2일간격으로간기능검사와흉부방사선을확인하는것이좋고, 혈압저하가나타나면주입속도를 1/2 혹은그이하로줄여서투여한다. 드물게서맥혹은심정지가나타날수있으며, 임시박동조율기삽입하고수일기다리면회복되는것이일반적이다. 다형심실빈맥의치료다형심실빈맥은 QT간격이정상이면서나타나는형태도있으나일반적으로는 QT간격의현저한연장과함께나타나는 TdP 이더흔하며, 심전도를통하여빠르게인지만된다면그치료는그리어렵지않고치료에대한반응도좋은편이다. 원인으로는선천성 / 후천성 QT연장증후군 (congenital or acquired long QT syndrome) 이있으며후천성 QT연장증후군은각종 27

4 J Neurocrit Care 2014;7(1):25-32 Table 1. Loading and maintenance doses of the common antiarrhythmic drugs Loading dose Onset of action Maintenance dose Diltiazem 0.25 mg/kg IV over 2 min 5 min 5 15 mg/hour Verapamil mg/kg IV over 2 min 5 min no data Esmolol 0.5 mg/kg over 1 min 5 min mg/kg/min Propranolol 0.15 mg/kg IV 5 min no data Digoxin 0.25 mg IV each 2 h, up to 1.5 mg 2 hour mg daily Lidocaine * 1-2 mg/kg over 2 min (half dose 30 min later if not responsive) Amiodarone 5 7 mg/kg over min, then g per day continuous IV or in divided oral doses until 10 g total, then mg per day maintenance 1-4 mg/min * Lidocaine is effective for the control of ventricular tachyarrhythmias in patients with ischemic heart diseases. It may cause decreased myocardial contractility or hypotension. However, the hemodynamic deterioration is relatively rare unless the patient suffers from severe congestive heart failure. Side effects include dizziness, sensory change, seizure, and coma. Oral amiodarone rarely causes hemodynamic changes, while intravenous amiodarone often induces peripheral vasodilation, hypotension, or bradycardia. Recommended initial loading dose is 150 mg over 10 min followed by infusion of mg/min. The speed of infusion of the initial loading (150 mg) may be reduced (for example, 150 mg over 1-4 hours) in patients with hypotension or congestive heart failure. hours 약물 (astemizole, terfenadine, ketoconazole, erythromycin, pentamidine), 전해질이상 (hypokalemia, hypomagnesemia), 심근허혈, 심부전등의원인에의하여이차적으로나타난다. 다형심실빈맥을보이는환자에서빈맥중축이여러방향으로변화하고 (twisting of points) 그시작이 PVC후서맥에의하여나타나며빈맥의첫박자가 giant T파로보이면 TdP 의가능성이많다 (Fig. 3). 이러한 TdP 은 magnesium 에의하여억제가잘되므로가장먼저해야할것은정맥주사로 magnesium 을주입하는것이다. 대략 MgSO4 1-2 gram을 5% 포도당용액에섞어서 1-2분에걸쳐서서서히주입하고이후부정맥의발생양상을관찰하여 PVC가완전히억제되지않으면 5-10분후동량을다시주입할수있다. 보통 magnesium 의혈중농도는조직내농도를반영하지못하므로혈액검사상정상농도일지라도 magnesium 을주사하는것이좋다. 보통중환자실에입실한환자는경구투여가불가능하여만성적으로영양결핍상태이고심부전이나기타원인으로이뇨제를쓰고있는경우가많아체내전해질이많이부족한경우가대부분이며항생제 / 진정제등 QT간격의연장을초래시킬수있는약물을복합적으로사용하므로 TdP 의발생에취약하다. 따라서혈중레벨이정상이어도 TdP 이발생한당일에약 10 g 정도의 magnesium 을주입 ( g/hr 혹은하루에걸쳐서서히주입 ) 하는것이좋고, 이후부정맥이없어질때까지혈중레벨이정상혹은약간높을정도로유지하는것이바람직하다. 단, 신부전환자에서는소변을통한 magnesium 배출이지연되므로 magnesium 에의한독성 ( 서맥, 저혈압 ) 이나타날가능성을고려하여신중히투여한다. 혈중칼륨레벨을높이면세포막을통한칼륨배출 이증가하므로재분극을촉진시켜 QT 간격을줄일수있어서 칼륨레벨을정상범위내에서높게유지하는것도좋다. 리도 케인을쓸수는있으나 magnesium 보다는그효과가뚜렷하지 않으므로 magnesium 주입후반응이없을경우에고려해볼 수있다. 단, amiodarone 은 QT 간격을더증가시키고부정맥을 악화시키므로사용하지않는것이좋다. 이러한치료와동시에 QT 연장의원인이될수있는약물 은중단하고전해질이상소견을교정하도록하면 TdP 은대부 분교정되는것이일반적이다. 이러한치료에도불구하고빈 맥이지속되는경우에는임시박동조율기를통하여심방혹은 심실조율을하면 QT 간격이줄어들어 TdP 의발생을줄일수 있다. 상심실성부정맥 (supraventricular tachyarrhythmias) 개요 QRS 파폭이좁고불규칙적인빈맥 (regular narrow QRS tachycardia) 대부분상심실빈맥 (paroxysmal supraventricular tachycardia) 혹은심방조동 (atrial flutter) 이며, 경동맥동마사지 (carotid sinus massage), adenosine 혹은 verapamil 주사에의하여종료되거나 심실박동수가줄어드는효과를볼수있다. 약물주입후재 발하면 diltiazem, verapamil, esmolol 등의주사제를연속주입 하거나경구약물로전환하여유지할수있으며, 장기적으로는 전극카테터절제법을고려하는것도좋다. 1 28

5 Cardiac Arrhythmias in the Intensive Care Units Nam GB Figure 4. A narrow QRS tachycardia in a 78 year-old male patient with biliary sepsis. Tachycardia was irregularly irregular with a heart rate of about 260 beats per minutes. Blood pressure decreased from 100 to 70mmHg due to the rapid heart rate. After infusion of intravenous diltiazem, heart rate was decreased to 160 beats per minutes, but blood pressure remained low at 70-80mmHg. Change to intravenous amiodarone (150mg over 2 hours, then continuous infusion at a rate of 0.5mg/min) further decreased heart rate to 130 beats per minutes with blood pressure increased to 90mmHg. QRS파폭이좁고불규칙적인빈맥 (irregular narrow QRS tachycardia) 일반적으로심방세동 (atrial fibrillation, AF) 이가장흔한원인이고, 호흡기환자에서는다원심방빈맥 (multifocal atrial tachycardia) 이그원인이되기도한다. 중환자실환자에서심방세동이갑자기발생하면이러한환자에서는패혈증, 심부전등다양한원인으로혈압이낮게유지되는환자가많으므로부정맥으로인하여추가적인혈압강하가나타나면교감신경흥분제를투여하여야할경우가많다 (Fig. 4). 이러한경우심방세동의심박수가더빨라지고심박수가더빨라지면혈압강하가악화되는악순환을밟게되므로, 중환자실에서심방세동이나타나면환자의경과가급격히나빠지는경우가많다. 심방세동이갑자기발생하였을경우증상이심하고혈역학적으로불안정하다면직류전류심장율동전환 (DC cardioversion) 을시행한다. 에너지는단상파형 (monophasic waveform shock) 의경우 200 J ( 혹은 300 J) 에서시작하여반응이없을경우 300 J, 360 J로증가시킨다. 이상파형 (biphasic shock) 의경우 100 J에 서시작하여 150 J, 200 J로증가시킨다. 심한증상이나혈역학적변화가크지않을경우에는일단관찰하거나심박수조절을시도할수있다. 심박수조절은 diltiazem, esmolol, digoxin 등의주사제를써서시도할수있으며맥박수가대략분당 60-90회정도유지되는것을목표로하나환자의상태를고려하여개별화하는것이필요하다. 하지만 diltiazem, esmolol 등으로혈압저하가나타나는경우가많아서약물을중단하여야할경우가많은데, 특히심부전이나패혈증이동반되어있을경우자주나타나며이러한경우에는 digoxin이나 amiodarone이효과적이다. 주사로주입할경우 amiodarone은부하용량주입 (loading) 중혈압저하가나타날수있으므로혈압에따라주사속도를반으로혹은그이하로줄여서주입하는것이필요하다. 대개 2-3일이내에맥박수와혈압이안정되므로이때경구제제로교체할수있다. 29

6 J Neurocrit Care 2014;7(1):25-32 Figure 5. Monomorphic ventricular tachycardia in a patient with structurally normal heart. A 12 year-old girl was admitted at the cardiac intensive care unit for the evaluation of recurrent palpitation and syncope. A 12-lead ECG taken during palpitation revealed a wide QRS tachycardia with right bundle branch block and left axis deviation. Small indentations (arrows) in the limb lead III suggest ventriculoatrial dissociation, a marker of ventricular tachycardia. The absence of structural heart disease and ECG morphologic characteristics (right bundle branch block and left axis) of VT confirmed the diagnosis of idiopathic fascicular tachycardia. Tachycardia was terminated by intravenous infusion of verapamil. A Dissociation due to sinus bradycardia and junctional escape rhythm B Dissociation due to complete atrio-ventricular block Figure 6. Differential diagnosis of atrioventricular dissociation. The rhythm strips show two different causes of atrioventricular (AV) dissociation. In the upper tracing (A), the cause of AV dissociation is slowed sinus rate (stars) with escape junctional rhythm, while the cause of dissociation in the bottom tracing (B) is complete AV block. Syncope or sudden cardiac deaths are rare in sinus bradycardia and junctional rhythm, whereas the risk is high in patients with bradycardia due to complete AV block. Temporary and/or permanent pacemaker is necessary in the latter condition. 전기잡음 (electrical noise) 의감별진단 간혹심전도, 특히감시심전도에전기잡음이들어갈경우심실빈맥과유사하게나타나는경우가있어서주의를요한다 (Fig. 5). 실제심실빈맥과달리전기잡음에서는잡음중간중간에 QRS complex 의날카로운파가정상 QRS파의간격과동일하게유지되므로이러한파형이관찰되면잡음을쉽게구별할수있다. 혹은동시에기록된혈량측정 (plethysmography) 파형이정상심장율동일때와변화가없이지속되거나, 동시에기록된다른유도의심전도가정상소견이면심실빈맥처럼보였던심전도파형이잡음이라는것을유추할수있다. 서맥성부정맥 (bradyarrhythmias) 개요 동결절부전 (sinus node dysfunction) 과방실전도장애 (AV conduction disturbance) 구별의중요성 동결절부전은실신의위험성은있지만급사의위험성은높지않고대개원인되는약물을줄이거나중단함으로써호전되는경우가많다. 반면에완전방실차단은실신의위험외에도급사의가능성을높이므로인공심장조율기를삽입하는것이필요하다. 따라서같은서맥이지만그예후와치료가상이하게달라지므로이두가지상태의심전도감별은임상적으로대단히중요하다 (Fig. 6). 반사성서맥 (reflex bradycardia) 동방결절이나방실결절, His-Purkinje system의이상없이자율신경계의항진 / 억제에의하여동성서맥이나전도장애가나타날수있다. 전형적인예는혈관미주신경실신이며이와비슷한반사반응 (reflex vagotonia) 이복부 / 골반부위의시술, 간조직검사, 복강경, 안과수술, 기관삽관, 기관지자극, 두개내압상승, 소변, 대변, 구토등다양한원인에의하여초래될수있고, 특히시술과관련되어환자의불안이크거나시술부 30

7 Cardiac Arrhythmias in the Intensive Care Units Nam GB 위의통증이심할경우에도이러한반사반응이나타날수있다. 대부분일과성이므로치료를필요로하지않지만치료가필요한경우에는 atropine, epinephrine 을사용할수있고, 장기적인예후는양호하다. 서맥성부정맥환자의치료 약물치료서맥의치료는서맥에의한증상이심하게존재하거나서맥으로인한혈역학적변화가초래될때적응이된다. 이때반드시서맥의원인 ( 가역적원인 ) 들의가능성을검토하고교정이가능하면교정하는것이중요하다. 대표적인가역적원인들로는약물 (digitalis, beta-blocker, Ca-channel blocker, class IA, IC antiarrhythmic agent), 전해질이상, 개심술후의일과성방실전도계손상 (hypothermia, inflammation), 급성심근경색, 일과성심근허혈, 부교감신경항진등이있다. 서맥성부정맥치료에서약물치료의역할은대부분심장조율전임시조치로필요한경우가대부분이다. Isoproterenol, atropine이이용되며, 동기능의호전이나방실결절전도차단시전도장애의호전에는도움이되나, 방실결절하부 (infranodal block) 전도차단에서는전도장애호전정도가뚜렷하지않아큰기대를하기어렵고허혈성심질환이있을경우에는사용에주의를요한다. Atropine ( mg) 은 5분간격으로주사할수있고 ( 최고 mg/kg), dopamine (5-20 g/ Kg/min), isoproterenol (2-10 g/mirn) 을연속주사하면서, 빠르게원인질환에대해평가하고경정맥박동조율기의필요성등을판단한다. 3 경피적박동조율기 (transcutaneous pacing) 경피적박동조율기는빠른시간내에전극 (electrode pad) 을피부에부착하고심박조율을실시할수있는유용한장치로서, 단기간내에서맥이회복될가능성이많을경우, 서맥이예상되나예방적으로경정맥박동조율기를삽입하기곤란할경우, 혹은안정적으로경정맥조율을실시하기전까지임시로심박조율이필요할경우에특히유용하다. 전극 pad는흉곽의앞, 뒤로부착하되전방전극 (anterior electrode, cathode) 은흉골좌측에맥박이최대로촉지되는점혹은심전도의 V3 위치에일치시키고후방전극 (posterior electrode, anode) 은전방전극의반대편으로좌측혹은우측의견갑골 (scapula)- 척추사이공간에부착한다. 일반적으로 msec의자극파를 ma 범위에서투여할수있도록되어있으며, 성인에서는대략 ma의전류로조율이가능하다. 종종조율역치 (capture threshold) 가높거나조율에따른동통이문제가되나전극과의 접촉피부면을알코올로닦거나면도후 pad 를부착하면조율 시의통증을줄일수있고, 의식이있는환자에서는 diazepam, morphine 을투여하는것이좋다. 조율은조율역치보다 10% 정도높은전류로유지하고반드시맥박과혈압 ( 혹은동맥압 monitor) 을측정하여효과적으로조율이되는지를확인하여야 한다. ( 맥박은조율기에의한근육수축과의혼동을피하기위 하여우측경동맥이나우측고동맥에서촉지한다 ). 4,5 경정맥심박조율 (transvenous temporary pacing) 경정맥심박조율은경피적심박조율에비하여좀더안정적으 로심박조율을시행할수있지만, 어느정도숙련된술자및시 설이필요하고, 간혹합병증이발생할수있어장단점이있다. 전극은주로대퇴정맥, 쇄골하정맥, 내경정맥을통하여삽 입되며, 6 Fr bipolar 혹은 quadripolar electrode 가가장흔하게 이용된다. 박동조율기는수일에서수주까지도유지할수있으 나오래될수록감염의위험이증가하므로가역적원인이아 니라면빨리영구형박동조율기로교체한다. 매일 threshold 와 심전도를확인하고전극삽입부위의감염여부도관찰한다. 4,5 결 론 중환자실입원환자에서나타나는부정맥은심전도를통한 감별진단이그치료에있어가장중요하며부정맥자체의특 성뿐아니라환자의다양한전신질환및심혈관상태를고려 하여접근하여야하는자세가필요하다. REFERENCES 1. Blomström-Lundqvist C, Scheinman MM, Aliot EM, Alpert JS, Calkins H, Camm AJ, et al. ACC/AHA/ESC guidelines for the management of patients with supraventricular arrhythmias--executive summary. a report of the American college of cardiology/american heart association task force on practice guidelines and the European society of cardiology committee for practice guidelines (writing committee to develop guidelines for the management of patients with supraventricular arrhythmias) developed in collaboration with NASPE-Heart Rhythm Society. J Am Coll Cardiol 2003;42: Zipes DP, Camm AJ, Borggrefe M, Buxton AE, Chaitman B, Fromer M, et al. ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: a report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (Writing Committee to Develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death). J Am Coll Cardiol 31

8 J Neurocrit Care 2014;7(1): ;48:e Gregoratos G, Abrams J, Epstein AE, Freedman RA, Hayes DL, Hlatky MA, et al. ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices--summary article: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (ACC/AHA/NASPE Committee to Update the 1998 Pacemaker Guidelines). J Am Coll Cardiol 2002;40: Barold SS, Zipes DP. Cardiac pacemakers and antiarrhythmic devices. In: Braunwald E. Heart Disease 5th ed. Philadelphia, WB Sauders. 1997: Sutton R. Sinus node disease. In: Ellebogen KA, Kay GN, Wilkoff BL. Clinical Cardiac Pacing. Philadelphia, WB Saunders. 1995:

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<B0E6C8F1B4EBB3BBB0FA20C0D3BBF3B0ADC1C E687770> 심전도연수강좌 : 처음시작하는사람들을위한심전도 연세대학교원주의과대학순환기내과학교실 안민수 Cardiac Electrophysiology I : Automaticity : 60-100 회 /min, His bundle : 40-60 회 /min Bundle branch : 20-40 회 /min Purkinje fiber : 20 회 /min Cardiac Electrophysiology