症例報告 PEDIATRIC CARDIOLOGY and CARDIAC SURGERY VOL. 28 NO. 2 (136 142) 高周波カテーテルアブレーションで根治した薬剤抵抗性潜在性右前中隔副伝導路の 10 カ月乳児例 藤田修平 1), 中村太地 1), 臼田和生 2) 3), 渡辺一洋 市田蕗子 3) 1), 畑崎喜芳 富山県立中央病院小児科 1), 富山県立中央病院内科循環器 2), 3) 富山大学小児科 Key words: anteroseptal accessory pathway, atrioventricular reentrant tachycardia, infant Successful Radiofrequency Catheter Ablation of a Concealed Anteroseptal Accessory Pathway in a 10-month-old Infant with Refractory Atrioventricular Reentry Tachycardia Shuhei Fujita 1, Taichi Nakamura 1, Kazuo Usuda 2, Kazuhiro Watanabe 3, Fukiko Ichida 3, Kiyoshi Hatasaki 1 1 Department of Pediatrics, Toyama Prefectural Central Hospital, Toyama, Japan, 2 Department of Cardiology, Toyama Prefectural Central Hospital, Toyama, Japan, 3 Department of Pediatrics, Toyama University, Toyama, Japan Although the incidence of atrioventricular reentry tachycardia (AVRT) using the right anteroseptal accessory pathway is low, the risk of atrioventricular block by radiofrequency catheter ablation (RFCA) of right anteroseptal accessory pathway is high. A 10-month-old infant with narrow QRS tachycardia was noted to have narrow QRS tachycardia at 280 bpm when she was referred to a general pediatrician for fever. The tachycardia was refractory to ATP and verapamil injection, per os administration of flecainide and bisoprolol, and frequent cardioversion and intravenous infusion of amiodarone were required. She was referred to our hospital for RFCA. An electrophysiological study (EPS) was performed, and the earliest ventriculoatrial (V-A) conduction was demonstrated near the His bundle electrogram, and retrograde conduction did not demonstrate decreased conduction properties. The atrial electrogram revealed a reset phenomenon by a single extra ventricular stimulus during tachycardia. From these results, AVRT using a right anteroseptal accessory pathway near the compact atrioventricular node was suspected. V-A conduction disappeared easily with catheter-induced mechanical trauma (bumping) at the earliest atrial activation site. We performed a low energy test application of radiofrequency energy at the earliest atrial activation site where the His potential was recorded. A junction rhythm appeared during radiofrequency applications. V-A conduction did not recur after catheter-induced mechanical trauma, so we applied radiofrequency application at the site. V-A conduction was completely eliminated, and it was impossible to induce AVRT. After RFCA, there were no abnormalities of atrioventricular node function. In infants with small cardiac dimensions, radiofrequency catheter ablation was possible and useful for a right anteroseptal accessory pathway. 要旨 10 280 bpm narrow QRS ATP EPS VA His His 2010 12 22 2012 1 16 930-8550 2-2-78 68 日本小児循環器学会雑誌第 28 巻第 2 号
137 VA VA bumping His junctional rhythm VA VA Bump VA はじめに 1 2-4 1 5-7 10 1 症例 症例 10 主訴 家族歴および既往歴 現病歴 9 narrow QRS 2 mg/kg/d 9 narrow QRS narrow QRS narrow QRS cardioversion 1 J/kg 1 30 narrow QRS cardioversion 1 J/kg 1 2 J/kg 1 3 mg/kg/day 1 mg/ day 5 narrow QRS cardioversion 1 J/kg 1 2 J/kg 1 5 mg/kg 5mg/kg/day 入院時現症 72 cm 9.6 kg 98/54 mmhg 138 / 20 / SpO2 99 顔貌 胸部 I II 腹部 四肢 入院時検査所見 1) 胸部エックス線検査 CTR 47 2) 心電図 118 bpm QRS 0.06 PQ 0.12 280 bpm narrow QRS II III avf P ATP AV Fig. 1 A-C 3) 心臓超音波検査 LVIDd 23 mm LVIDs 12 mm IVS 4 mm LVPWs 6 mm LVFS 0.48 LVEF83 4) 血液検査 WBC 11,100/ l RBC 447 10 4 / l Hb 11.8 g/dl HCT 35. Plt 56.2 10 4 / l TP 6.5 g/dl ALB 4.5 g/ dl AST 45 IU/L ALT 36 IU/L ALP 402 IU/L LD 245 IU/L CK 78 IU/L -GT 16 IU/L T-Bil 0.4 mg/dl BUN 4 mg/dl CRE 0.2 mg/dl Na 139 meq/l K 4.3 meq/l Cl 107 meq/l CRP 0.04 mg/dl TSH 2.11 IU/ml F-T3 3.6 pg/ml F-T4 1.2 ng/dl BNP 19.8 pg/ ml AMD 100 ng/ml DEA 50 ng/ml 平成 24 年 3 月 1 日 69
138 A B C Fig.1 入院後経過および外来経過 Electrocardiogram. ( A ) Re s t i n g e l e c t ro c a rd i o g r a m ( E C G ) showed sinus rhythm, 118 beat per minutes (bpm) and no delta wave. (B) ECG showed narrow QRS tachycardia at 280 bpm. (C) E C G s h owe d n a r row Q RS ta c hyc a rd i a stopped with AV block after administration of ATP. 入院第 6 病日に電気生理学検査 カテーテルアブ 入院後 患児の頻拍発作はフレカイニド β遮断薬等 レーションを施行した 右大腿静脈より 5Fr 8Fr 左 の従来の薬物治療に不応であり 頻回の cardioversion 大腿静脈より 4Fr sheath をそれぞれ挿入した 右大腿 アミオダロン持続静注が必要となってきており 難治 静脈より挿入した 5Fr sheath から 1.6Fr 電極カテーテ 性上室頻拍と判断した 高周波カテーテルアブレー ル PATHFINDER mini 6 Japan Lifeline Tokyo ションでの根治の可能性があり適応となり得ると判断 Japan を 3 本挿入しそれぞれ HRA His RVA へ配置 した 心電図モニター下に病棟内管理とし アミオダ した CS カテーテルは左大腿静脈より右ジャドキン ロン投与は中止 ビソプロロール内服のみ継続とした スカテーテルとガイドワイヤーを用いて 1.6Fr 電極カ 70 日本小児循環器学会雑誌 第28巻 第２号
139 PATHFINDER mini 6 Japan Lifeline Tokyo Japan Fig. 2 A, B His jump up narrow QRS HR 250 bpm TCL 240 ms His5-6 Fig. 3 His reset ATP EPT Steero standard Boston Scientific Natick MA VA Fig. 4 His 50 1-9W 5 VA VA Bumping AV VA bumping 50 7W 21 Fig. 5 A-C VA 2 考察 Koch 7 bumping Fig.2 Catheter positions. Catheters were positioned in HRA, RVA, CS and His bundle. (A) RAO, (B) LAO. HRA: high right atrium, RVA: right ventricular apex, CS: coronary sinus, RAO: Right anterior oblique protection, LAO: left anterior oblique protection 平成 24 年 3 月 1 日 71
140 Fig.3 Intracardiac records during narrow QRS tachycardia. The earliest retrograde atrial activation was recorded in HBE 5-6. I: ECG lead I, II: ECG lead II, V1; ECG lead V1, HRA: high right atrium, HBE: his bundle electrogram, RVA: right ventricular apex, CS: coronary sinus, STIM: stimulus Fig.4 Intracardiac records during accessory pathway mapping on ventricular pacing. ECG showing ventriculoatrial (V-A) dissociation after bumping (arrow). A showed retrograde V-A conduction followed by sinus rhythm. 72 日本小児循環器学会雑誌第 28 巻第 2 号
141 A. B. C. Fig.5 Catheter position and intracardiac records of radiofrequency catheter ablation (RFCA) site. (A) Sinus rhythm. A very small His bundle electrogram was recorded at ABL. (B) Ventricular pacing. A continuous ventriculoatrial (V-A) conduction and accessory pathway potential was recorded. (C) Catheter position of RFCA. ABL: ablation catheter 8 8 Mandapati 127 36 96 136 2 4 32 2 7 Pecht 88 9 Schaffer 554 74 3 5 7 accelerated junctional rhythm 7 10, 11 Catheter-induced mechanical trauma bumping 12, 13 bumping 12, 13 Mahaim fiber bumping 14 bumping 11 Bumping bumping 平成 24 年 3 月 1 日 73
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