室间隔完整型肺动脉闭锁及肺动脉瓣狭窄的手术治疗

目的探讨新生儿、婴儿室间隔完整型肺动脉闭锁及危重型肺动脉瓣狭窄的手术治疗。方法19例患儿,其中室间隔完整型肺动脉膜性闭锁10例,危重型肺动脉瓣狭窄9例。15例经胸正中切口体外循环心脏不停跳下完成手术,4例经左胸后外侧切口非体外循环下完成手术。除早期1例同期行动脉导管未闭（PDA）结扎及卵圆孔未闭缝合术外,其余18例均保留PDA、单纯切开肺动脉瓣。结果本组围术期死亡2例,院外死亡1例。其余16例术后当日肺动脉跨瓣压差为37—132mmHg,平均61mmHg;2周后为26～77mmHg,平均43mmHg,较术后早期明显降低（P〈0．05）。出院前不吸氧下测动脉血氧饱和度78％～92％,平均85％,较术前明显增高（P〈0．05）。随访PDA均闭合,右心室较术前明显增大,三尖瓣反流消失或明显减轻,房水平分流消失。结论对室间隔完整型肺动脉闭锁及危重型肺动脉瓣狭窄实施单纯肺动脉瓣切开术治疗安全有效。     

单纯肺动脉瓣疏通术初期治疗危重婴幼儿室间隔完整型肺动脉闭锁

目的:探讨低龄危重婴幼儿室间隔完整型肺动脉闭锁,及危重肺动脉瓣狭窄的初期外科治疗方法。方法:2009年6月至2013年6月,我院共对10例室间隔完整型肺动脉闭锁及2例危重肺动脉瓣狭窄婴幼儿患者,施行经胸正中切口非体外循环下,单纯肺动脉瓣疏通术(改良Brock术)治疗,术中保留动脉导管未闭,三尖瓣反流未做处理。患儿年龄2~9个月,体质量4.3~10kg,平均6.4kg。所有患者均合并动脉导管未闭及房间隔缺损或者卵圆孔未闭,术前患者末梢血氧饱和度62%~73%,平均69%。结果:本组围术期死亡1例(8.3%),死亡原因为术后持续低氧血症,其余11例术后均缺氧状态改善,经皮血氧饱和度上升至84%~93%,平均89%。术后测得肺动脉瓣跨瓣压差为11~28mmHg(1mmHg=0.133kPa),平均15.6mmHg,术后随访11例,PDA均闭合,三尖瓣反流由术前大量转为少量或者消失。结论:作为危重婴幼儿的初期治疗,对于发绀严重,生长发育差,不能耐受体外循环的危重室间隔完整型肺动脉闭锁及危重肺动脉瓣狭窄患儿,Brock术可获得满意的治疗效果。     

Echocardiographic diagnosis of pulmonary atresia with intact ventricular septum.

The echocardiographic features of pulmonary valvar atresia with intact ventricular septum are described. The pulmonary valve fails to open during systole: there is a large pre-systolic 'a' wave dip, but the pulmonary valve membrane then returns to its closed diastolic position where it remains for the remainder of the cardiac cycle. The echocardiogram also provides valuable information about right ventricular size, the tricuspid valve, and aorta-mitral and aorta-septal relations.     

Management algorithm in pulmonary atresia with intact ventricular septum.

Pulmonary atresia with intact ventricular septum (PAIVS) is a disease with remarkable morphologic variability, affecting not only the pulmonary valve but also the tricuspid valve, the RV cavity and coronary arteries. With advances in interventional techniques and congenital heart surgery, the management of PAIVS continues to evolve. This review is an attempt at providing a practical approach to the management of this disease. The basis of our approach is morphologic classification as derived from echocardiography and angiography. Group A, patients with good sized RV and membranous atresia, the primary procedure at presentation is radiofrequency (RF) valvotomy. Often it is the only procedure required in this group with the most favourable outcome. Patients with severely hypoplastic RV (Group C) are managed along the lines of hearts with single ventricle physiology. The treatment at presentation is patent ductus arteriosus (PDA) stenting with balloon atrial septostomy or conventional modified Blalock Taussig (BT) shunt. Bidirectional Glenn shunt may be done 6-12 months later followed by Fontan completion after a suitable interval. Patients in Group B, the intermediate group, are those with borderline RV size, usually with attenuated trabecular component but well developed infundibulum. The treatment at presentation is RF valvotomy and PDA stenting +/- balloon atrial septostomy. Surgical re-interventions are not uncommonly required viz. bidirectional Glenn shunt when the RV fails to grow adequately (11/2 - ventricle repair) and right ventricular outflow tract (RVOT) reconstruction for subvalvar obstruction or small pulmonary annulus. Catheter based interventions viz. repeat balloon dilatation or device closure of patent foramen ovale (PFO) may also be required in some patients.     

Morphological variations in pulmonary atresia with intact ventricular septum.

The morphological features of a series of 37 specimens of pulmonary atresia with intact ventricular septum were reviewed with particular emphasis on features which might influence the results of pulmonary valvotomy. The degree of right heart hypoplasia was quantified by measuring right and left heart dimensions and comparing them with 20 normal infant hearts. Right ventricular cavity size was usually smaller than normal but constituted a spectrum ranging from tiny to a dilated ventricle larger than normal. There was a positive correlation between triscuspid annular size and right ventricular size but no correlation between the size of the pulmonary artery and the right ventricle. Successful pulmonary valvotomy with subsequent adequate right ventricular function would have been precluded by a tiny right ventricular cavity or infundibular atresia in 14 specimens and by severe tricuspid stenosis or regurgitation in an additional 4. Severe right or left ventricular endocardial fibroelastosis may have adversely affected ventricular function in several others. Ten specimens displayed convex bulging of the left ventricular septal surface. If these these anatomical findings are representative for the condition as a whole, they provide a good explanation for its disastrous prognosis.     

Morphological variations in pulmonary atresia with intact ventricular septum.

The morphological features of a series of 37 specimens of pulmonary atresia with intact ventricular septum were reviewed with particular emphasis on features which might influence the results of pulmonary valvotomy. The degree of right heart hypoplasia was quantified by measuring right and left heart dimensions and comparing them with 20 normal infant hearts. Right ventricular cavity size was usually smaller than normal but constituted a spectrum ranging from tiny to a dilated ventricle larger than normal. There was a positive correlation between triscuspid annular size and right ventricular size but no correlation between the size of the pulmonary artery and the right ventricle. Successful pulmonary valvotomy with subsequent adequate right ventricular function would have been precluded by a tiny right ventricular cavity or infundibular atresia in 14 specimens and by severe tricuspid stenosis or regurgitation in an additional 4. Severe right or left ventricular endocardial fibroelastosis may have adversely affected ventricular function in several others. Ten specimens displayed convex bulging of the left ventricular septal surface. If these these anatomical findings are representative for the condition as a whole, they provide a good explanation for its disastrous prognosis.     

Catheterization in neonates with pulmonary atresia with intact ventricular septum.

Cardiac catheterization is infrequently required in babies with pulmonary atresia with intact ventricular septum. The main indications are to decide on the best form of treatment, the options being determined by the right ventricular as well as infundibular morphology and the presence of right-ventricle dependent coronary circulation. In most cases, an interventional approach is appropriate. This can consist of radiofrequency or laser perforation of the atretic pulmonary valve, combined with balloon dilation. In some patients, additional stenting of the arterial duct may be needed.     

Necrotizing enterocolitis in pulmonary atresia with intact ventricular septum

Necrotizing enterocolitis (NEC) occurred in 2 neonates with pulmonary atresia and intact ventricular septum. Both infants underwent open heart surgery for the insertion of a right ventricular outflow tract patch under profound hypothermia, surface cooling and a fibrillating heart, without circulatory arrest. In both patients the development of NEC preceded both the cardiac catheterization study and open heart surgery. Urgent repair of the cardiac lesion was undertaken in an attempt at improving the critical bowel wall ischemia. Postoperatively, exacerbation of the NEC reached an advanced stage rapidly leading to the death of the patients. Recommendations regarding the management of future cases exhibiting this potentially lethal combination of disease are presented.     

Operative balloon dilatation for pulmonary atresia with intact ventricular septum.

In six infants with pulmonary atresia and intact ventricular septum operative balloon dilatation was used to achieve continuity between the right ventricle and the main pulmonary artery as the initial procedure. Two of the six subsequently needed an aortico pulmonary shunt. All six are alive and well.     

Guided transcatheter valvulotomy in pulmonary atresia with intact ventricular septum

Transcatheter valvulotomy in pulmonary atresia with an intact ventricular septum can be used as a first step to create biventricular circulation and to stimulate further development of the hypoplastic right ventricle. We describe our experience in a case of a neonate with this congenital cardiac defect who underwent successful transcatheter perforation of the atretic pulmonary valve. This report highlights the utility of a special technique based on the use of a gooseneck snare positioned just above the atretic valve to guide the advance of a coronary guidewire. Other therapeutic alternatives are considered.     

Congenitally corrected transposition with pulmonary atresia and intact ventricular septum

We describe a patient with the rare association of the heart in the left chest, congenitally corrected transposition, pulmonary atresia and an intact ventricular septum. There were associated fistulous communications between the morphologically left ventricle and the coronary arteries. Diagnosis was made by echocardiography, and subsequently confirmed by cardiac catheterization.     

Operative balloon dilatation for pulmonary atresia with intact ventricular septum

In six infants with pulmonary atresia and intact ventricular septum operative balloon dilatation was used to achieve continuity between the right ventricle and the main pulmonary artery as the initial procedure. Two of the six subsequently needed an aortico pulmonary shunt. All six are alive and well.     

Coronary arterial abnormalities in pulmonary atresia with intact ventricular septum

The incidence and severity of abnormalities of the coronary arteries were evaluated in 35 necropsy patients with pulmonary atresia and an intact ventricular septum. Right ventricular to coronary artery fistulous connections were found in more than 60% of the cases. All patients with fistulous connections had histologic abnormalities of the coronary arteries. In 50% the lesions were mild, with medial and intimal thickening producing up to moderate luminal stenosis. In 50% there was loss of normal arterial wall structure and severe narrowing or obliteration of the arterial lumen. The coronary arterial fistulas and histologic abnormalities were prevalent in those with underdevelopment of the tricuspid valve and right ventricular cavity but were not found in patients with a normal or dilated tricuspid valve anulus. The coronary arterial abnormalities were found in more than 80% of patients with a tricuspid valve/mitral valve ratio less than 1. A single coronary artery occurred in 6 patients (17%) of this series. In 80% of those with 1 coronary artery arising from the other, the aberrantly arising coronary artery crossed anteriorly to the pulmonary artery and could be at risk in surgical attempts to reconstruct the right ventricular outflow. Aortography is recommended if the coronary arteries are not clearly delineated on ventricular cineangiocardiography.