Detection of coronary artery abnormalities in tetralogy of Fallot by two-dimensional echocardiography

Patients with tetralogy of Fallot have a 5% to 19% incidence rate of abnormal distribution of coronary arteries. These abnormalities are usually detected by angiography and influence the timing and mortality rate of surgery. This study evaluates two-dimensional echocardiography as a method of assessing coronary artery distribution in tetralogy of Fallot. Forty-five consecutive patients with tetralogy of Fallot, aged 0.1 to 20.5 years (mean 5.7 +/- 4.3), had prospective two-dimensional echocardiographic studies to examine the branching patterns of the coronary arteries and to determine the presence or absence of a branch from the right or left coronary artery that crossed the right ventricular outflow tract. The first two patients had known coronary abnormalities and served as learning models. All other echocardiographic studies were performed without knowledge of angiographic or surgical findings. Twenty-two studies were completed before coronary angiography (group A) and 23 after angiography (group B). All eight patients (18%) with coronary abnormalities were correctly identified by two-dimensional echocardiography (five in group A and three in group B). Three had bilateral anterior descending coronary arteries originating from the left and right coronary arteries, two had the anterior descending artery originating from the right coronary artery, two had a large conal branch from the right coronary artery and one had origin of both left and right coronary arteries from a single left ostium. All abnormal coronary arteries were visualized crossing the right ventricular outflow tract, whereas all 21 small conal branches from the right coronary artery were not seen in the right ventricular outflow tract.(ABSTRACT TRUNCATED AT 250 WORDS)     

Early results and follow-up of balloon angioplasty for branch pulmonary artery stenoses

Two hundred eighteen balloon angioplasty procedures were performed in 135 patients with branch pulmonary artery stenoses from June 1984 to February 1989. Arteries were dilated in patients with tetralogy of Fallot (n = 49), tetralogy of Fallot/pulmonary atresia (n = 64), isolated peripheral pulmonary artery stenoses (n = 58) and "other" lesions (the majority had truncus arteriosus or single ventricle and surgically induced pulmonary artery stenoses (n = 47). Mean age at dilation was 6.6 +/- 6.3 years (range 1 month to 38.5 years). The mean diameter of the lesion increased from 3.8 +/- 1.7 to 5.5 +/- 2.1 mm with dilation (p = 0.001). The overall success rate was 58% (127 of 218 dilations), assessed by the following criteria: an increase greater than or equal to 50% of predilation diameter, an increase greater than 20% in flow to the affected lung or a decrease greater than 20% in systolic right ventricular to aortic pressure ratio. Success did not correlate with patient age. Mean balloon to artery ratio was higher in successful (4.2) than in failed (3.0) angioplasty procedures (p = 0.0001). There were four early deaths: two of the patients had pulmonary artery rupture with angioplasty performed less than 1 month after pulmonary artery surgery. An aneurysm occurred in 11 arteries and transient pulmonary edema in four patients. At angiography performed a mean of 10 months (range 1 to 54) after dilation, the mean diameter of 57 arteries was unchanged (5.5 versus 5.4 mm). However, 5 of 32 initially successfully dilated vessels had returned to predilation size as a result of restenosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Expanding indications for the treatment of pulmonary artery stenosis in children by using cutting balloon angioplasty.

OBJECTIVES: To evaluate the role of cutting balloon angioplasty in children with pulmonary artery stenosis. BACKGROUND: Pulmonary artery stenoses can be either congenital or secondary to postoperative scar formation. Isolated multiple small-vessel pulmonary artery stenoses are very rare. No surgical procedures for their treatment are currently available. METHODS: We report on four patients in whom standard and high-pressure balloon angioplasty had failed. Three of the four (2.5-, 3-, and 3.5-years-old; two girls) had isolated multiple peripheral pulmonary artery stenosis. The fourth patient was an 11-month-old girl (8 kg) with tetralogy of Fallot and hypoplastic pulmonary artery branches treated with the implantation of two stents in the pulmonary arteries. During the follow-up this patient developed severe intrastent restenosis and showed severely hypoplasic distal left pulmonary artery. RESULTS: We treated 11 vessels. The mean vessel diameter increased by 81% (P<0.0001) and RV/LV pressure ratio decreased from 1.15 to 0.75 (P=0.05). Patient treated for intrastent restenosis underwent successful complete tetralogy of Fallot repair. None of the patients suffered procedure-related complications. At a median follow-up of 18 months, results were stable and no late complications had occurred. CONCLUSIONS: Cutting balloon angioplasty is a promising technique for the treatment of highly challenging pathologies such as small vessel pulmonary artery stenoses and intrastent restenosis.     

干下型室间隔缺损法乐氏四联症20例临床分析

本文对253例法乐氏四联症中20例(7.9%)室间隔缺损位于肺动脉瓣下者的临床资料及手术结果分析表明,本组患者临床上紫绀多偏轻;B型超声心动图及心室造影显示,右心室流出道较宽,肺动脉发育不良亦少见。但绝大多数病例需补片加宽右室流出道或跨环补片,否则术后易残留右心排血受阻。     

Primitive ventricle with normally related great vessels and stenotic subpulmonary outlet chamber. Angiographic differentiation from tetralogy of Fallot

Four patients with primitive ventricle and normally related great vessels with stenotic subpulmonary outlet chamber (Holmes' heart with pulmonary stenosis) are reported. The history, physical examination, and chest x-ray film are not helpful in distinguishing Holmes' heart with pulmonary stenosis from tetralogy of Fallot. Electrocardiogram often provides the first clue to the presence of Holmes' heart; left axis deviation with or without left ventricular hypertrophy is an unusual finding in tetralogy of Fallot, but common in Holmes' heart. Selective ventriculography is diagnostic: the right ventricular outflow chamber overlies the aortic root and aortic valve in the frontal view in Holmes' heart with pulmonary stenosis, but is to the left of the aortic valve in tetralogy of Fallot; no ventricular septum can be identified in Holmes' heart. The diagnosis can be suspected in a child with clinical features of tetralogy of Fallot but atypical electrocardiogram, and can be established by angiography.     

Primitive ventricle with normally related great vessels and stenotic subpulmonary outlet chamber. Angiographic differentiation from tetralogy of Fallot.

Four patients with primitive ventricle and normally related great vessels with stenotic subpulmonary outlet chamber (Holmes' heart with pulmonary stenosis) are reported. The history, physical examination, and chest x-ray film are not helpful in distinguishing Holmes' heart with pulmonary stenosis from tetralogy of Fallot. Electrocardiogram often provides the first clue to the presence of Holmes' heart; left axis deviation with or without left ventricular hypertrophy is an unusual finding in tetralogy of Fallot, but common in Holmes' heart. Selective ventriculography is diagnostic: the right ventricular outflow chamber overlies the aortic root and aortic valve in the frontal view in Holmes' heart with pulmonary stenosis, but is to the left of the aortic valve in tetralogy of Fallot; no ventricular septum can be identified in Holmes' heart. The diagnosis can be suspected in a child with clinical features of tetralogy of Fallot but atypical electrocardiogram, and can be established by angiography.     

Predictors of hemodynamically successful left pulmonary artery stent implantation in patients after repair of tetralogy of Fallot

OBJECTIVES: Left pulmonary artery stenosis is a well-known postoperative complication in patients with tetralogy of Fallot. Recently, balloon expandable intravascular stents have been widely used to relieve those lesions. However, the increase in left pulmonary blood flow is not adequate in some patients, although the vessels are suitably dilated. This study evaluated the predictors of hemodynamical improvement. METHODS: The study population consisted of nine patients with morphologically successful stent implantation for left pulmonary artery stenosis after repair of tetralogy of Fallot. Patients were divided into two groups. Four patients had hemodynamical improvement by stent implantation, with relative perfusion of the left lung of over 30% of total pulmonary perfusion. The other five patients had relative perfusion of the left lung of under 30% of total pulmonary perfusion after stent implantation. The timing of stent implantation and the morphological features of pulmonary artery were compared between the two groups. RESULTS: In hemodynamically improved patients, the stent implantation was performed earlier(6.1 +/- 3.5 vs 16.1 +/- 6.5 years old, p = 0.029), and the interval between surgical repair and stenting was shorter (3.7 +/- 2.7 vs 11.3 +/- 4.7 years, p = 0.025). There was no difference in the left pulmonary artery diameter after stenting, but the right pulmonary artery diameter was significantly smaller in hemodynamically improved patients (99.0 +/- 23.7 vs 135.0 +/- 15.1% normal, p = 0.027). CONCLUSIONS: Effective stent implantation for left pulmonary artery stenosis in patients with tetralogy of Fallot after repair must be performed before compensatory right pulmonary artery growth occurs.     

Tetralogy of fallot with diminutive pulmonary arteries: Preoperative pulmonary valve dilation and transcatheter rehabilitation of pulmonary arteries

Objectives. The study sought to determine the results of a novel transcatheter management approach in tetralogy of Fallot with diminutive pulmonary arteries.

Background. Tetralogy of Fallot with diminutive pulmonary arteries and severe pulmonary stenosis is rare and resembles tetralogy of Fallot with pulmonary stresia: There is a high incidence of aortopulmonary collateral channels, arborization abnormalities, stenoses and need for multiple operations. Because a combined catheter-surgery approach facilitates repair in these patients, such an approach may benefit those with diminative pulmonary arteries and pulmonary stenosis.

Methods. Clinical, catheterization and surgical data were studied retrospectively for 10 such patients undergoing preoperative pulmonary valve balloon dilation, among other transcatheter interventions, from January 1989 to January 1995.

Results. Initially, the Nakata index ranged from 20 to 98 mm²/m² (mean 67 ± 28 mm²/m²). The pulmonary valve was first balloon dilated (mean balloon/annulus 1.5 ± 0.3), and the mean initial valve annulus Z score (−40 ± 1) increased to −3.3 ± 1.1 (p < 0.01). Other interventions included branch pulmonary artery balloon dilation (7 patients, 23 vessels) and coil embolization of aortopulmonary collateral channels (8 patients, 31 collateral channels). At preoperative follow-up catheterization, the mean pulmonary annulus Z score was −3.1 ± 0.7, and the aorta index increased to 143 ± 84 mm²/m² (p < 0.03). All patients underwent complete surgical repair successfully. At a mean follow-up period of 2.6 ± 2 years, right ventricular pressure was < 70% systemic in all patients and <50% systemic in seven.

Conclusions. In patients with tetralogy of Fallot, severe pulmonary stenosis and diminutive pulmonary arteries, initial pulmonary valve balloon dilation increases the annulus Z score and anterograde pulmonary blood flow and facilitates simultaneous coiling of sertopulmonary collateral channels and access for branch pulmonary artery dilation, all of which results in pulmonary artery growth, simpligying surgical management.     

Hemodynamic evaluation of 221 patients after intracardiac repair of tetralogy of Fallot

Cardiac catheterization and angiocardiographic studies were performed in 221 patients an average of 2 years (range 2 weeks to 10 years) after intracardiac repair of tetralogy of Fallot. The group represented 32.5 percent of the postoperative survivors. The postoperative result was classified as “excellent” (43 percent), “good” (35 percent), “satisfactory” (7 percent) or “unsatisfactory” (14 percent) on the basis of right ventricular peak systolic pressure, right ventricle to pulmonary artery peak systolic gradient and presence of a persistent large or small left to right shunt at the ventricular level. Unsatisfactory results were associated with obstructive pulmonary vascular disease (four patients), severe malformations with obstruction of the right ventricular outflow tract and/or a left to right shunt with a Qp:Qs ratio of greater than 1.5:1 or with currently uncorrectable obstructive anomalies of the right ventricular outflow tract or pulmonary arteries.The postoperative result depended upon the amount of reconstruction of the right ventricular outflow tract and the caliber of the pulmonary arteries. Patients who required a systemic to pulmonary artery anastomosis before total correction and those who required a prosthetic patch for the right ventricular outflow tract fared worse than younger patients who had minimal resection of the right ventricular outflow tract. Pulmonary insufficiency was detected in 94 percent of patients with a right ventricular outflow tract prosthesis and in 10 percent of those who had infundibulectomy alone. The insufficiency was well tolerated clinically and hemodynamically unless there was distal obstruction of the pulmonary artery or its branches.Postoperative catheterization is necessary to assess the immediate and long-term operative results in patients with tetralogy of Fallot. Total correction of tetralogy of Fallot as a primary procedure provides acceptable hemodynamic results even in children less than 4 years of age, providing that the right ventricular outflow tract obstruction can be relieved and that pulmonary insufficiency is not aggravated by increased main pulmonary arterial pressure.     

Computed tomographic angiography in tetralogy of Fallot

Echocardiography is often inadequate for imaging tetralogy of Fallot, prompting cineangiography. This study prospectively evaluated multidetector computed tomographic angiography for preoperative evaluation of tetralogy of Fallot in 112 consecutive patients. Forty-eight had nonconfluent or hypoplastic pulmonary arteries (mean z-score, -2; range, -11.1-0.13) permitting only palliative or no surgery; 64 had adequate pulmonary artery anatomy (mean z-score, 0.59; range, -2.53-3.4) allowing total repair. The surgical data of 50 patients who underwent total correction were compared with transthoracic echocardiography and multidetector computed tomographic angiography findings. Multidetector computed tomographic angiography tended to reveal unsuspected collaterals and coronary abnormalities besides outlining the right ventricular outflow tract and pulmonary artery branches. The branch pulmonary artery diameter z-score was the most important determinant of surgical strategy, with the worst figures being associated with no surgical options or palliative surgery, and the best figures leading to corrective surgery. The mean radiation dose was 3.45 mSv. Multidetector computed tomographic angiography is a powerful supplement to echocardiography in the preoperative evaluation of tetralogy of Fallot.     

Associated coronary and cardiac anomalies in the tetralogy of Fallot. An angiographic study

Numerous studies have pointed out the frequent association of tetralogy of Fallot (TF) with other cardiovascular defects and coronary tree anomalies. We found cardiac defects in 181 (68%) out of 265 patients with TF investigated by catheterization and selective coronary angiography. These anomalies were isolated in 88 cases (49%) and associated with others in 93 patients. In the case of an isolated anomaly associated with TF, the coronary tree was involved in 37.5% and the cardiovascular system in the remaining 62.5%; in the case of two anomalies, the coronary system was involved in 66% of the patients and the cardiovascular apparatus in 34%; in the case of three or more anomalies, the coronary arteries were involved in 71% and the cardiovascular system in 29%. Anomalies in the course and/or distribution of coronary arteries were present in 96 patients (36%): 10 had a single coronary ostium, 13 a left anterior descending artery arising from the right coronary artery, one a circumflex artery arising from the right coronary artery. Small fistulas between coronary arteries and the pulmonary artery were found in 20 cases; anastomoses between coronary and bronchial arteries or right atrium in 42. In 39 patients we observed a large conus artery or large anterior ventricular branches crossing the right ventricle. A right aortic arch was found in 56 patients (21%), a stenosis of the trunk and/or the peripheral pulmonary artery in 35 (13%) and pulmonary artery atresia in five. Four patients showed a complete atrioventricular canal, three an atrial septal defect (primum type) with cleft of the mitral valve, 61 (23%) an atrial septal defect (ostium secundum). Eleven patients had anomalies of the systemic venous return, 26 (10%) a patent ductus arteriosus. Four patients had valvular abnormalities. In our series, a large proportion of cardiac defects associated with TF consists of anomalies of coronary arteries. Our data confirm the usefulness of performing preoperatively routine coronary angiography in patients with complex congenital heart disease.     

Assessment of the branches of the pulmonary artery by 2-dimensional echocardiography

Sixty three cases of Fallot's tetralogy aged from 1 month to 30 years old, were studied by 2D echocardiography to evaluate the diameter of the pulmonary arteries and to detect stenosis of the main pulmonary arteries. The right pulmonary artery was visualised clearly enough to be measured in all 63 cases whereas the left pulmonary artery could only be adequately recorded in 58/63 cases. The junction of the two pulmonary arteries was confirmed by 2D echo in 61/63 cases; in two cases, the left pulmonary artery was not connected (2/63), confirmed at angiography and surgery. Six stenoses of the pulmonary arteries, confirmed surgically (6/7), were detected by 2D echo but there were also 3 false positive results. The pulmonary arteries were measured from suprasternal views; the values obtained ranged from 3 to 15 mm. There was a good correlation with the angiographic measurements (R = 0.81 for the right pulmonary, and R = 0.82 for the left pulmonary arteries). Good correlations were also observed between the peroperative and 2D echo measurements (R = 0.84 for the right pulmonary; R = 0.77 for the left pulmonary artery). 2D echocardiography is a non-invasive reliable technique for visualising the pulmonary arteries and their origin, for measuring the calibre of these vessels and for detecting severe proximal pulmonary artery stenosis.     

Natural history of supravalvular aortic stenosis and pulmonary artery stenosis

Data from 35 patients with supravalvular aortic stenosis or pulmonary artery stenosis, or both, undergoing cardiac catheterization between 1973 and 1989 were analyzed retrospectively. Twenty-seven patients had supravalvular aortic stenosis: 11 required surgery after the first investigation and 8 (80%) of 10 others undergoing serial investigation showed an increase in the left ventricle to aorta pressure gradient. Angiographic measurements showed that the increase in the aortic pressure gradient was related to failure of normal growth of the ascending aorta lumen. Nineteen patients had pulmonary artery stenosis, with a right ventricular pressure greater than 33 mm Hg. At restudy, right ventricular pressure had decreased in 9 (82%) of 11 patients. This decrease in right ventricular pressure was associated with an increase in the systolic distensibility of the proximal pulmonary arteries, although there was no increase in the diastolic diameters. One patient had a rapid early increase in right ventricular pressure and no pulmonary artery growth. In two patients, multiple peripheral pulmonary artery stenoses became evident with time and produced persistent right ventricular hypertension. Supravalvular aortic stenosis is usually a progressive lesion, with an increase in left ventricular outflow tract pressure gradient related to poor growth of the ascending aorta. Pulmonary artery stenosis usually improves and only rarely limits prognosis.     

小儿法乐四联症磁共振成像与电影磁共振诊断

评价磁共振成像（ＭＲＩ）及电影磁共振成像（ｃｉｎｅ－ＭＲＩ）在小儿法乐四联症的诊断价值。采用ＭＲＩ及ｃｉｎｅ－ＭＲＩ成像技术,检查了２５例法乐四联症患儿,并与超声心动图（ＵＣＧ）和心血管造影（ＣＡＧ）进行比较,全部病例均经手术证实。结果表明,ＭＲＩ及ｃｉｎｅ－ＭＲＩ能清晰地显示法乐四联症的室间隔缺损,主动脉骑跨,肺动脉狭窄和右心室肥厚的基本病理改变,可进行定性及定量诊断。本组资料显示,ＭＲＩ、ＵＣＧ、及手术（ＯＰ）对室间隔缺损大小测量无显著性差异（Ｐ＝０．３２８）。ＭＲＩ对主动脉骑跨率测量与ＵＣＧ、ＣＡＧ结果相一致。肺动脉主干及左、右肺动脉内径测量与ＵＣＧ、ＣＡＧ相关有显著性。ＭＲＩ及ｃｉｎｅ－ＭＲＩ能对法乐四联症基本病理畸形做出准确诊断,手术证实与ＣＡＧ诊断结果基本相同,对左、右肺动脉的显示优于ＵＣＧ,可做为法乐四联症术前诊断的主要检查方法。     

Isolated supravalvular pulmonary stenosis in a 25-day-old newborn infant: an occasional and early diagnosis

Pulmonary stenosis comprises variable pathologic features from the right ventricular outflow tract to the peripheral pulmonary arteries. Most frequently, the obstruction occurs at the level of the pulmonary valve; however, it occurs less frequently at the infindibular level. It can occur as part of more congenital cardiac malformations such as tetralogy of Fallot, complete transposition of great arteries, or atrial septal defect. Proximal pulmonary artery stenosis has also been reported as an acquired lesion in infants treated for congenital heart disease. Primary isolated supravalvular pulmonary stenosis is less common. We present a case of primary isolated pulmonary artery stenosis in an asymptomatic 25-day-old newborn infant.     

Two-dimensional echocardiographic identification of hemitruncus: Anomalous origin of one pulmonary artery from ascending aorta with the other pulmonary artery arising normally from right ventricle

Two-dimensional echocardiography (2DE) was performed on a 2300 gm newborn who presented with congestive heart failure. Clinical examination suggested left-to-right shunt with pulmonary hypertension. Cardiac catheterization and angiography demonstrated origin of the right pulmonary artery (RPA) from the aorta. Retrospectively, this feature (anomalous RPA) had been present on 2DE. A second patient aged 2 years had evidence of ventricular septal defect with large left-to-right shunt early in life. Gradual development of infundibular stenosis and clinical cyanosis ensued. 2DE showed subaortic ventricular septal defect with infundibular stenosis. Cardiac catheterization and angiography confirmed tetralogy of Fallot with origin of the left pulmonary artery (LPA) from the aorta. Retrospective review of 2DE showed the anomalous LPA arising from the side of the ascending aorta.     

Balloon dilation of the right ventricular outflow tract in tetralogy of Fallot: a palliative procedure.

Fifteen patients requiring palliation for tetralogy of Fallot were treated by balloon dilation because of hypercyanotic spells. The mean age at dilation was 1.9 +/- 0.7 years (range 0.5-3), and the mean weight 9.8 +/- 2.1 kg (range 6.0-13.5). Dilation of the outflow tract was combined with dilation of the left and/or right pulmonary arteries in 5 patients. Successful dilation was achieved in 12 patients (80%), but failed in 3 patients with hypoplastic pulmonary arteries. In one patient, the stenosis of the right pulmonary artery could not be dilated because of a very sharp angle at the site of the stenosis. Two of the 3 patients in whom the procedure failed died of severe cyanotic spells within 24 hours of the unsuccessful procedure. No major complications occurred during or after the procedure in the cases undergoing successful dilation. The arterial oxygen saturation increased significantly, from 71 +/- 5.7% to 89 +/- 3.9%, immediately after the procedure (p < 0.005). During a period of follow up of 6 +/- 3.7 months (range 1-13), the procedure was repeated on 3 occasions, and successfully accomplished in 2 of these. In conclusion, balloon dilation is a satisfactory palliative procedure for tetralogy of Fallot in those units in which total correction is not performed under 2 to 3 years of age.     

A comparison of magnetic resonance angiography with conventional angiography in the diagnosis of tetralogy of Fallot

AIMS: Our purpose was to assess the value of magnetic resonance angiography as a non-invasive alternative to catheterization in the evaluation of patients with tetralogy of Fallot, including those with pulmonary atresia. METHODS AND RESULTS: We evaluated prospectively, using magnetic resonance angiography, 30 patients, aged from 1 to 18 years, 15 with tetralogy of Fallot and pulmonary stenosis, and 15 with pulmonary atresia. The studies obtained using magnetic resonance provided adequate visualization of the aorta, and provided excellent imaging of the pulmonary trunk and its right and left branches. Compared with catheterization, magnetic resonance had 100 percent sensitivity, specificity and accuracy for defining the presence or absence of the pulmonary arteries. Magnetic resonance also had 93.9 percent sensitivity, 98.2 percent specificity, and 96.7 percent accuracy for detection of stenosis or hypoplasia of the pulmonary arteries. We detected 25 major aortopulmonary collateral arteries with magnetic resonance, but only 22 with conventional angiography. There was complete agreement between the two methods in detecting patency of the arterial duct in 6 patients, and of Blalock-Taussig shunts in 12 patients. CONCLUSION: Magnetic resonance angiography is a useful tool in the evaluation of patients with tetralogy of Fallot. It can be considered a non-invasive alternative to cardiac catheterization in the evaluation of the pulmonary vascular anatomy.     

Intravascular stents for management of pulmonary artery and right ventricular outflow obstruction

Summary This study was performed to determine the efficacy of balloon-expandable stents in the treatment of branch pulmonary artery-stenoses and conduit stenosis in children. A total of eight stainless steel stents were implanted in seven patients. Three patients had tetralogy of Fallot with pulmonary artery stenosis following total correction, one patient had conduit stenosis following correction of transposition of the great arteries, one patient had intra-cardiac conduit stenosis after septation for single left ventricle, and two patients had pulmonary artery stenosis after Fontan operation. Six stents were placed in the branch pulmonary arteries, one in the extracardiac conduit, and one in the intracardiac conduit. The mean age at implantation was 13 ± 3 years and the mean weight 37 ± 12kg. Follow-up time ranged from 0.3–2 years. The diameter of pulmonary arteries with stenoses increased from 5.6 ± 2.2 mm to 10.6 ± 1.8 mm (n = 7). The systolic pressure gradient decreased from 56 ± 26 mmHg to 22 ± 16 mmHg (n = 5). No embolization or thrombotic event has been noted. One stent placed in the intracardiac conduit was compressed and fractured. These data indicate that balloon-expandable stents are useful in the treatment of pulmonary artery branch stenoses and extracardiac conduit stenosis in children. The use of stents for intracardiac stenosis may result in stent fracture.     

Reliability of intraoperative transesophageal echocardiography during Tetralogy of Fallot repair

There is limited information available concerning the accuracy of intraoperative transesophageal echocardiography (TEE) in predicting the extent of residual abnormalities after recovery from surgical repair of tetralogy of Fallot. Therefore, we investigated differences between the results of final postbypass TEE and those of postrecovery (mean, 6 days after surgery) transthoracic echocardiography in a total of 28 consecutive pediatric patients who underwent repair of tetralogy of Fallot with biplane or multiplane TEE. Both postbypass and postrecovery echocardiographic examinations included measurements of the right ventricle (RV)-main pulmonary artery (PA) and the main PA-branch PA peak instantaneous gradients, the degree of pulmonary valvar insufficiency, and color Doppler interrogation of the ventricular septum for residual defects. The RV-main PA gradient did not change significantly: 15 +/- 13 vs 18 +/- 14 mmHg (postbypass versus postrecovery, mean +/- SD). None of the patients had a decrease of > or = 10 mmHg; and only one patient had an increase of > or = 15 mmHg. There also was no change in the degree of pulmonary insufficiency (3.0 +/- 1.2 versus 3.1 +/- 1.1, using a scale of 0 to 4). Only one of the seven very small (< or = 2 mm) residual ventricular septal defects was not discovered during postbypass TEE. However, postrecovery transthoracic echocardiography detected significant branch PA stenosis (peak gradient, > or = 15 mmHg) in five patients (18%) that was not detected during postbypass TEE (P < 0.03). Of the branch PA stenoses that were not detected during TEE, four were left and one was right. Conclusions: Postbypass TEE after tetralogy of Fallot repair reliably predicts residual postrecovery hemodynamic abnormalities, except for branch PA stenosis.