经导管射频打孔并球囊扩张治疗婴儿室间隔完整的肺动脉瓣闭锁

Radiofrequency perforation and balloon valvuloplasty in infants with pulmonary atresia and intact ventricular septum

目的探讨经导管射频瓣膜打孔并球囊扩张治疗婴儿室间隔完整的肺动脉瓣闭锁(PA/IVS)有效性和安全性。方法 4例患儿年龄分别为11、9、9个月和12 d,体重4～10 kg[(7.6±2.2)kg]。均具有紫绀和动脉导管未闭连续性杂音的临床表现。超声心动图诊断后,在全麻下作右心室造影确定右心室腔由3部分结构组成,漏斗部呈长管形,无冠状动脉异常。适合经导管射频打孔并球囊扩张术治疗。射频瓣膜打孔能量5～8 W,持续时间2～5 s,一般2次;预扩球囊3 mm×20 mm～5 mm×20 mm,6～14 atm;肺动脉瓣扩张球囊10 mm×30 mm～14 mm×30 mm,有效扩张1～2次。手术持续时间120～150 min,X 线暴露时间25.4～43.9 min。结果技术成功率100%,除1例新生儿发生心脏穿孔早期死亡外,其他3例无任何并发症。存活3例随访4～12个月,1例需外科解除右室流出道梗阻,2例可择期封堵动脉导管未闭。结论经导管射频瓣膜打孔并球囊扩张术治疗 PA/IVS 需严格掌握适应证,规范操作,可作为替代或延迟外科开胸手术治疗的一种方法。

Objective To investigate the efficacy and safety of percutaneous radiofrequency perforation and valvuloplasty in infants with pulmonary atresia with intact ventricular septum （PA/IVS） . Methods Four infants （ body weight 4 - 10 kg） aged 11 months,9 months, 12 days and 9 months old, respectively, were hospitalized for dyspnea and cyanosis. All patients had a continuous murmur in the left second intercostal space. Doppler echocardiogram showed membranous pulmonary atresia with intact ventricular septum. Right ventriculogram showed a tripartite right ventricle, vasiform infundibulum, and membranous pulmonary valve atresia without ventriculocoronary connections. Descending thoracic aortogram showed good-sized confluent pulmonary arteries being filled from a ductus arteriosus. All the patients were taken up for radiofrequency perforation followed by a balloon dilatation. A 6F Judkins right coronary guiding catheter was positioned in the right ventricular outflow tract and under the atretic pulmonary valve membrane. The radiofrequency perforation catheter along with coaxial injectable catheter was then passed through the right coronary guiding catheter, using it as the guide to the imperforate membrane. The proximal end of the radiofrequency perforation catheter was then connected to radiofrcquency generator. After the cusps of pulmonary valve were perforated, the coaxial injectable catheter was moved into the main pulmonary artery. A tiny floppy-tipped coronary guidewire was then passed through the coaxial injectable catheter into the main pulmonary artery and directed through the patent ductus arteriosns into the descending thoracic aorta or directed into pulmonary arteriola. Thereafter, serial balloon dilation catheters were introduced across the pulmonary valve, and dilations were sequentially performed with increasing balloon diameters. The balloon was dilated until the concave of the balloons disappeared. The radiofrequency energy （5 to 8 W） was delivered for 2 to 5 seconds once, but commonly twice, to perforate the valves. After a predilation with a 3 nun x 20 mm to 5 nun x 20 nun balloon at 6 - 14 atm pressure, the valve was subsequently dilated with 10 mm × 30 mm to 14 mm × 30 mm balloon once or twice. The duration of procedures was 120 to 150 min and exposure time was 25.4 to 43.9 min. Results The primary procedure was successful in all the infants except one who died early of cardiac perforation with tamponade. After a follow-up period ranging from 2 to 8 months （ mean 4. 3 m）, the remaining 3 survivors achieved complete biventricular circulation. Two of them were awaiting occlusion of the patent ductns arteriosns and 1 needed right ventricular outflow tract reconstruction because of infundibular obstruction. Conclusion PA/IVS consists of 0.7% to 3.1% of congenital heart defects. 85% of the untreated patients die within half a year. Surgical repair for the infants with PA/IVS is associated with a high mortality. In carefully selected patients with PA/IVS, radiofrequency perforation and balloon dilatation of the pulmonary valve is feasible and may represent a new alternative to surgery due to its low mortality and avoidance of cardiopulmonary bypass.