Severe left diaphragmatic hernia limits size of fetal left heart more than does right diaphragmatic hernia.

OBJECTIVES: To assess whether severity of congenital diaphragmatic hernia (CDH) correlates with the degree of left heart hypoplasia and left ventricle (LV) output, and to determine if factors leading to abnormal fetal hemodynamics, such as compression and reduced LV preload, contribute to left heart hypoplasia. METHODS: This was a retrospective cross-sectional study of fetuses at 16-37 weeks' gestation that were diagnosed with CDH between 2000 and 2010. Lung-to-head ratio (LHR), liver position and side of the hernia were determined from stored ultrasound images. CDH severity was dichotomized based on LHR and liver position. The dimensions of mitral (MV) and aortic (AV) valves and LV were measured, and right and left ventricular outputs were recorded. RESULTS: In total, 188 fetuses with CDH were included in the study, 171 with left CDH and 17 with right CDH. Fetuses with severe left CDH had a smaller MV (Z = -2.24 ± 1.3 vs -1.33 ± 1.08), AV (Z = -1.39 ± 1.21 vs -0.51 ± 1.05) and LV volume (Z = -4.23 ± -2.71 vs -2.08 ± 3.15) and had lower LV output (26 ± 10% vs 32 ± 10%) than those with mild CDH. MV and AV in fetuses with right CDH (MV, Z = -0.83 ± 1.19 and AV, Z = -0.71 ± 1.07) were larger than those in fetuses with left CDH, but LV outputs were similarly diminished, regardless of hernia side. Severe dextroposition and abnormal liver position were associated independently with smaller left heart, while LHR was not. CONCLUSION: The severity of left heart hypoplasia correlates with the severity of CDH. Altered fetal hemodynamics, leading to decreased LV output, occurs in both right- and left-sided CDH, but the additional compressive effect on the left heart is seen only when the hernia is left-sided. Improved knowledge of the physiology of this disease may lead to advances in therapy and better risk assessment for use in counseling affected families.

Twin-reversed arterial perfusion sequence associated with decreased fetal cerebral vascular impedance.

OBJECTIVES: Twin-reversed arterial perfusion (TRAP) sequence affects 1% of monochorionic twin pregnancies and is caused by abnormal vascular connections between a pump twin and an acardiac mass. The effects of abnormal vascular connections on cerebral vasculature in the pump twin are unknown. We hypothesize that abnormal cerebral vascular impedance, as assessed by the pulsatility index (PI), is present in pump twins and that fetal intervention alters cerebral impedance. METHODS: Fetal echocardiograms performed between 2010 and 2013 in pregnancies diagnosed with TRAP (n = 19), recorded at presentation, and uncomplicated monochorionic twin pregnancies (controls, n = 18; 36 fetuses) were analyzed. In all subjects, the middle cerebral artery (MCA)-PI, combined cardiac output (CCO) and cardiothoracic ratio were calculated, and the values for cases and controls were compared. RESULTS: The mean gestational age at the time of echocardiography was 20 weeks in both groups. MCA-PI was lower in TRAP cases than in controls (1.55 (95% CI, 1.47-1.64) vs 1.74 (95% CI, 1.65-1.82), respectively; P = 0.004). CCO in TRAP cases was mildly elevated for gestational age (199.7 (95% CI, 138.4-261.1) mL/min) compared with that of controls (131.4 (95% CI, 102.2-160.7) mL/min). In six TRAP cases with a second echocardiogram available, the mean MCA-PI increased after intervention, from 1.5 (95% CI, 1.3-1.7) to 1.8 (95% CI, 1.4-2.2). CONCLUSIONS: TRAP pump twins have lower cerebral vascular impedance than do controls, suggestive of a brain-sparing effect. MCA-PI appeared to increase in a small group of pump twins after intervention. These findings suggest a fetal cerebral autoregulatory response to a high cardiac output state that begins to change after fetal intervention. The long-term implications for neurodevelopmental outcome warrant further study.

The Ross procedure in children and young adults: a word of caution.

BACKGROUND: Disease of the aortic valve in children and young adults is a complex entity whose management is the subject of controversy. The Ross and the Ross-Konno procedures have become the primary choices for aortic valve replacement in children because of growth potential, optimal hemodynamic performance, and lack of the need for anticoagulation. However, concern persists regarding the longevity of the pulmonary autograft, especially in patients with aortic insufficiency. METHODS: Between June 1993 and February 2000, 72 Ross and Ross-Konno procedures were performed at our institution: 81% of the patients were less than 15 years old. Preoperative, postoperative, and follow-up clinical, echocardiographic, and hemodynamic data were reviewed. Statistical analysis was performed to identify the risk factors for deteriorating autograft function. RESULTS: Aortic insufficiency was an indication for the Ross procedure in 17 patients and mixed lesions with predominant aortic insufficiency in 10. Of the 45 other patients, 32 had aortic stenosis and 13 had mixed lesions with predominant aortic stenosis. There were no deaths during a follow-up of 5 to 80 months. Autograft reoperation was necessary in the follow-up period in 7 patients for severe aortic insufficiency. Moderate insufficiency was identified in 5 additional patients. Aortic insufficiency or predominant aortic insufficiency, as a preoperative hemodynamic indication for the Ross procedure, reached statistical significance (P =.031) as a risk factor for autograft failure. CONCLUSION: The Ross and the Ross-Konno procedures have changed the prognosis of children and young adults with complex aortic valve disease. However, the Ross procedure should be performed with caution in older children in whom aortic insufficiency is a preoperative hemodynamic indication. Further follow-up to delineate the risk factors for autograft dysfunction in children and young adults is necessary to better define the indications for the Ross procedure.

Perioperative administration of angiotensin converting enzyme inhibitors decreases the severity and duration of pleural effusions following bidirectional cavopulmonary anastomosis.

BACKGROUND: Pleural effusions after bidirectional cavopulmonary anastomosis remain a significant cause of morbidity. Prolonged effusions in such patients have been associated with persistent elevations in plasma renin and angiotensin II. METHODS: We conducted a controlled study in 36 patients (median age 8 months) undergoing bidirectional cavopulmonary anastomosis. Enalapril (5 mcg/kg) was administered intravenously within 1 hour of surgery and every 12 hours thereafter in 18 patients; when these patients were tolerating feeds, enalapril was switched to enteral captopril (3 mg/kg/day) every 8 hours. The other 18 patients did not receive perioperative angiotensin converting enzyme inhibitors. Using standardized criteria for discontinuation of chest tubes (< 2 mL/kg/day), volume and duration of pleural drainage were compared between groups. RESULTS. There were no differences between groups in demographic, diagnostic, or hemodynamic factors. There was no difference in cardiopulmonary bypass time between groups and no difference in postoperative pulmonary arterial pressures. The duration of pleural drainage was shorter (2.2+/-1.4 vs 5.9+/-1.4 days, p<0.001) and the volume less during the first 24 hours (4.7+/-1.2 vs 7.7+/-2.1 mL/kg, p<0.001) and overall (10.6+/-2.4 vs 19.6+/-4.5 mL/kg, p<0.001) in patients who received angiotensin converting enzyme inhibitors than those who did not. Readmission for persistent effusions was required in 3 patients who did not receive angiotensin converting enzyme inhibitors and none who did (p=0.11). CONCLUSIONS: Perioperative administration of angiotensin converting enzyme inhibitors is associated with decreased severity and duration of pleural effusions following bidirectional cavopulmonary anastomosis.

Improved surgical outcome after fetal diagnosis of hypoplastic left heart syndrome.

BACKGROUND: Hypoplastic left heart syndrome (HLHS) is frequently diagnosed prenatally, but this has not been shown to improve surgical outcome. METHODS AND RESULTS: We reviewed patients with HLHS between July 1992 and March 1999 to determine the influence of prenatal diagnosis on preoperative clinical status, outcomes of stage 1 surgery, and parental decisions regarding care. Of 88 patients, 33 were diagnosed prenatally and 55 after birth. Of 33 prenatally diagnosed patients, 22 were live-born, and pregnancy was terminated in 11. Of 22 prenatally diagnosed patients who were live-born, 14 underwent surgery, and parents elected to forego treatment in 8. Of 55 patients diagnosed postnatally, 38 underwent surgery, and 17 did not because of parental decisions or clinical considerations. Prenatally diagnosed patients were less likely to undergo surgery than patients diagnosed after birth (P:=0.008). Among live-born infants, there was a similar rate of nonintervention. Among patients who underwent surgery, survival was 75% (39/52). All patients who had a prenatal diagnosis and underwent surgery survived, whereas only 25 of 38 postnatally diagnosed patients survived (P:=0.009). Patients diagnosed prenatally had a lower incidence of preoperative acidosis (P:=0.02), tricuspid regurgitation (P:=0.001), and ventricular dysfunction (P:=0.004). They were also less likely to need preoperative inotropic medications or bicarbonate (P:=0.005). Preoperative factors correlating with early mortality included postnatal diagnosis (P:=0.009), more severe acidosis (P:=0.03), need for bicarbonate or inotropes (P:=0.008 and 0.04), and ventricular dysfunction (P:=0.05). CONCLUSIONS: Prenatal diagnosis of HLHS was associated with improved preoperative clinical status and with improved survival after first-stage palliation in comparison with patients diagnosed after birth.

Inhaled nitric oxide in neonates with persistent pulmonary hypertension.

To investigate the oxygenation and haemodynamic dose response to inhaled nitric oxide in neonates with persistent pulmonary hypertension (PPHN), we gave seven neonates nitric oxide and measured directly pulmonary arterial pressure. Inhaled nitric oxide produced peak improvement in oxygenation at 5 parts per million (ppm) whereas peak improvement in the pulmonary-to-systemic arterial pressure ratio did not occur until a nitric oxide dose of 20 ppm, which suggests that an Initial dose of 20 ppm is optimum for the treatment of PPHN.

Elective primary repair of acyanotic tetralogy of Fallot in early infancy: overall outcome and impact on the pulmonary valve.

OBJECTIVES: We sought to determine if early primary repair of acyanotic tetralogy of Fallot (ToF) can be performed safely with low requirement for transannular patching (TAP) and thereafter allow normal right ventricular outflow tract (RVOT) growth. BACKGROUND: Early primary repair of ToF normalizes intracardiac flow patterns, which may allow subsequent normal RVOT growth. Traditionally repair is deferred until symptoms occur or children are deemed of adequate size for operative risk to be acceptable because of a perceived increased requirement for TAP in small infants. METHODS: Between July 1992 and March 1999, 42 acyanotic infants aged 4 to 87 days (median 62) and weight 2.6 to 6.6 kg (median 4.55) underwent complete repair of ToF. Pulmonary annulus measured 4 to 10.5 mm (median 6.5) with "z-value" of-5.6 to +3.0 (median -1.9). RVOT reconstruction was tailored to each patient; pulmonary valvotomy was performed in 26, main pulmonary arterioplasty in 22, and infundibular patching in 2. Only 10 (24%) required TAP. RESULTS: Postoperative RVOT gradient was 0 to 30 mm Hg (median 10) and pRV/pLV ratio 0.3 to 0.6 (median 0.44). Pulmonary insufficiency was trivial/mild. There were no deaths. Junctional ectopic tachycardia developed in seven; only one required treatment. ICU stay was 2 to 14 days (median 4) and hospital stay 4 to 22 days (median 7). At follow-up 12 to 64 months later (median 38) there were no deaths. One child required reoperation for recurrent RVOT obstruction and two required balloon pulmonary arterioplasty. Follow-up RVOT gradient was 0 to 36 mm Hg (median 12), unchanged from early postoperative condition, and median z-value was -1.2 (-2.8 to +2.5); pulmonary insufficiency remained trivial/mild. CONCLUSIONS: Complete repair of acyanotic ToF can be performed in early infancy with low morbidity and mortality and low requirement for TAP. Though results are not statistically significant, early repair may allow normal RVOT growth thereafter.

Evaluation of the morphology of the oval fossa for placement of devices.

OBJECTIVES: First, to examine the morphology of heart specimens with defects of the oval fossa so as to define the factors that facilitate appropriate selection of the size of devices used for inteventional closure. Second, to examine the relationship between morphology and transthoracic and transesophageal echocardiography. BACKGROUND: The success of transcatheter closure is influenced by the variable morphology of deficiencies with the oval fossa, and of the relationship of the fossa itself to adjacent structures. More appropriate selection could reduce the incidence of failures. METHODS: From over 100 specimens in the cardiac registry at the University of California, San Francisco, we judged 16 hearts with atrial septal defects within the oval fossa, either in isolation or associated with other cardiac malformation, to be suitable for this study. We measured the dimensions of the defect and the surrounding rims of the fossa. All values were normalized to the diameter of the aortic root. RESULTS: A fenestrated defect was present in 9 specimens (56%). The shape defect itself was oval in all specimens, with a ratio of major to minor axes of 1.70 + 0.63. The major axis took one of three main directions with respect to the vertical plane: in 11 specimens (69%o) it was at horizontal; in 3 (19%) it was at oblique at an angle of 45 degrees; and in 2 (12%) it was vertical. Discordance was noted in some hearts between the major axis of the defect and that of the oval fossa. Structures closest to the rim of the fossa were the aortic mound, the coronary sinus, and the hinge point of the aortic leaflet of the mitral valve. CONCLUSIONS: Extrapolating from these specimens permitted identification of the major and minor axes of the atrial septal defect by transthoracic and transesophageal echocardiography. Our study has identified landmarks and dimensions that may be employed to improve effectiveness of selection of patients for transcatheter closure of defects within the oval fossa.

Transesophageal echocardiographic predictors for successful transcatheter closure of defects within the oval fossa using the CardioSEAL septal occlusion device.

OBJECTIVES: To define the utility of transesophageal echocardiography in predicting the likelihood of a successful procedure and residual shunting in patients undergoing transcatheter closure of defects within the oval fossa using the CardioSEAL device. BACKGROUND: Transesophageal echocardiography is used to monitor transcatheter closure of interatrial defects within the the oval fossa, but predictors of successful closure and residual shunting have yet to be determined. METHODS: We reviewed transesophageal echocardiograms obtained from 26 consecutive patients undergoing attempted transcatheter closure of interatrial defects within the oval fossa between January, 1997 and May, 1998. Assessment of the atrial septum, the septal defect, and the rims of the oval fossa bordering the defect was performed in 3 planes: longitudinal, 4-chamber, and basal short-axis. RESULTS: Closure proved successful in 24 patients (92%). The defect was significantly larger, and the anterosuperior rim of the defect smaller, in the 2 patients in whom occlusion was not successful. Residual shunting 24 hrs after closure was detected in 14 patients. Significant predictors of leakage included smaller posterior and superior rims, a larger shunt prior to closure, and herniation of a one left atrial arm of the device into the right atrium. In all cases, the sites of leakage were the superior rim of the defect at the superior cavo-atrial junction, and the anterosuperior rim behind the aortic root. Herniation of a left atrial arm into the right atrium was seen in 7 patients (29%). In all, it was the anterosuperior arm which herniated Doppler color flow was suboptimal in detecting residual leaks, and was enhanced substantially with the use of contrast echocardiography. CONCLUSIONS: Transesophageal echocardiography allows excellent assessment of the oval fossa and deficiencies of its floor in all of their dimensions. It is an important tool for guiding the deployment of the occlusion device in patients undergoing attempted transcatheter closure of defects within the fossa. Contrast echocardiography should be used for optimal detection of residual shunting.

Surgical intervention for complications of transcatheter dilation procedures in congenital heart disease.

BACKGROUND: Transcatheter interventions have assumed an important role in the management of many forms of congenital heart disease. While complications of transcatheter interventions are uncommon and usually minor, significant complications requiring operation do occur on occasion. The purpose of this report is to present our experiences with seven such complications, and to review the literature on this topic. METHODS: Seven patients who required operation after a transcatheter dilation procedure between 1992 and 1998 are described. Three patients required retrieval of retained foreign bodies (stents or balloons), and repair of the underlying abnormality. Two patients underwent repair of fistulas between 2 great vessels, or a great vessel and a cardiac chamber. One patient required operation for a postdilation aneurysm. One patient underwent urgent repair of severe aortic regurgitation after balloon aortic valvuloplasty. RESULTS: All patients survived and are doing well, with no further need for catheter or operative intervention, from 8 months to 6 years after operation. Additional reported complications requiring operation are discussed as well. CONCLUSIONS: Operation for complications of catheter interventions in congenital heart disease is seldom necessary. Though uncommon, a variety of such complications may occur, including vascular, valvar, intracardiac, and foreign body complications. When operation is required, results are typically very good.

Asymmetrically short tendinous cords causing congenital tricuspid regurgitation: improved understanding of tricuspid valvar dysplasia in the era of color flow echocardiography.

BACKGROUND: Tricuspid regurgitation as a manifestation of an isolated congenital anomaly of the tricuspid valve is rare. Cross-sectional and color Doppler echocardiography allow improved evaluation of tricuspid valvar function. As a result, the heterogeneous category of congenital tricuspid valvar dysplasia may be better understood from a functional point of view. We are reporting a distinct entity in which tricuspid valvar regurgitation results from failure of coaptation due to short tendinous cords tethering the septal leaflet. PATIENTS AND RESULTS: Three children with significant primary tricuspid regurgitation were evaluated, treated, and followed. On echocardiographic evaluation, a central regurgitant jet of moderate or severe degree was directed toward the atrial septum through poorly coapting tricuspid valvar leaflets, which did not approximate due to tethering of the septal leaflet by abnormally short cords. In one patient, the tricuspid valve was otherwise normal; in the other two the leaflets and cords were also thickened. Two patients underwent surgery at 9 and 11 years of age. The cords tethering the septal leaflet were augmented by interposing appropriate lengths of expanded polytetrafluoroethylene suture and performing commissural annuloplasty. Both patients are asymptomatic 33 and 42 months postoperatively, with mild residual tricuspid regurgitation that has not changed since surgery. The other patient, an 8 month-old infant, has not yet undergone surgery. CONCLUSIONS: Asymmetric tendinous cords of the tricuspid valve causing tethering of the septal leaflet is a distinct cause of tricuspid regurgitation that can be recognized with echocardiography. Although rare, the importance of recognizing this lesion lies in its being readily amenable to surgical repair.

Pediatric bacterial endocarditis. Treatment and prophylaxis.

Endocarditis is a rare but serious complication often related to complex CHD. The incidence, particularly among smaller infants with cyanotic heart disease, seems to be increasing. The pathophysiology is related to a combination of host and bacterial factors that predispose to endothelial colonization and infection. Diagnosis, although occasionally difficult, is life saving, but the treatment is prolonged. Prophylaxis before appropriate procedures may significantly decrease the risk for development in appropriate patients.

Echocardiographic diagnosis alone for the complete repair of major congenital heart defects.

OBJECTIVES: The study was done to determine the diagnostic accuracy of echocardiography alone in the preoperative diagnosis of children with major congenital heart defects undergoing primary complete repair. BACKGROUND: Although echocardiography is well established as the first-line imaging technique for the diagnosis of all forms of congenital heart disease, most institutions continue to perform cardiac catheterization prior to complete repair of more complex defects. METHODS: To determine the diagnostic accuracy of echocardiography alone and echocardiography plus catheterization, we reviewed the records of 503 children with major congenital heart defects who underwent primary complete repair at our institution between July 1992 and June 1997. We included children with transposition of the great arteries, tetralogy of Fallot, double-chamber right ventricle, interrupted aortic arch, aortic coarctation, atrioventricular septal defect, truncus arteriosus, aortopulmonary septal defect, and totally anomalous pulmonary venous return. We excluded children with less complex defects such as isolated shunt lesions, as well as those with the most complex defects that would require surgical palliation (e.g., functional univentricular heart). We defined major errors as those that increased the surgical risk and minor errors as those that did not. Errors in diagnosis were determined at surgery. RESULTS: Eighty-two percent of children (412 of 503) underwent surgery after preoperative diagnosis by echocardiography alone. There were 9 major (2%) and 10 minor errors in the echocardiography alone group and 7 major and 5 minor errors in the echocardiography plus catheterization group. The most common type of error was misidentification of coronary artery anatomy in patients with transposition of the great arteries. No error in either group resulted in surgical morbidity or mortality. CONCLUSIONS: This study suggests that echocardiography alone is an accurate tool for the preoperative diagnosis of major congenital heart defects in most children undergoing primary complete repair, and may obviate the need for routine diagnostic catheterization.

Atrioventricular septal defect with common valvar orifice and tetralogy of Fallot revisited: making a case for primary repair in infancy.

Atrioventricular septal defect with common valvar orifice and tetralogy of Fallot is a rare combination of congenital cardiac anomalies. Approaches to this lesion have tended to emphasize either staged repair or complete repair beyond infancy. Between July 1992 and August 1997, nine patients underwent repair of complete atrioventricular septal defect with tetralogy of Fallot. One patient, aged 9.6 years at the time of repair, had previously undergone construction of a modified Blalock-Taussig shunt. Primary complete repair was performed in the other 8 patients at ages ranging from 2.5 to 16 months (median 4.6 months), and all but one were infants. All patients had a Rastelli type C defect, a single ventricular septal defect with inlet and outlet components, and malalignment of the muscular outlet septum with subpulmonary stenosis. A single patch technique, with closure of the zone of apposition ('cleft') in the left atrioventricular valve, was used in all eight patients undergoing primary repair, while a double patch was employed in the previously palliated older patient. In all cases of repair using a single patch, the anterosuperior bridging leaflet was divided obliquely to the right, following the malaligned outlet septum, in order to avoid subaortic obstruction. Repair of the right ventricular outflow tract included infundibular myectomy in eight, pulmonary valvotomy in four, infundibular or transannular patching in three and one, respectively, and reconstruction with a valved allograft conduit in two patients. There was no early mortality or significant morbidity. At a median follow-up of 45 months, there had been one death related to non-cardiac causes and no reinterventions. Left atrioventricular valvar regurgitation was moderate or mild in two patients, and right atrioventricular valvar regurgitation was mild in one patient. No patient had more than mild pulmonary regurgitation or a gradient across the right ventricular outflow tract in excess of 18 mm Hg. Our results demonstrate that primary repair of atrioventricular septal defect with tetralogy of Fallot can be performed with excellent early and mid-term results in young infants. Although it has been suggested that a technique utilizing oblique division of the anterosuperior bridging leaflet may lead to high rates of atrioventricular valvar regurgitation, medium-term atrioventricular valvar function in the present cohort of patients has been excellent.

Intramyocardial hematoma causing cardiac tamponade after repair of Ebstein malformation: erroneous echocardiographic diagnosis as intracavitary thrombus.

Intramyocardial hematoma is an uncommon lesion, most often occurring after chest trauma, aortic valve disease, acute myocardial infarction, or coronary artery bypass surgery. We describe a 17-year-old patient who experienced cardiac tamponade after repair of Ebstein malformation. The malformation was caused by an enlarging intramyocardial hematoma that extended from the right atrium to the atrialized right ventricle. The hematoma was incorrectly diagnosed by echocardiography as an intracavitary thrombus, and the correct diagnosis was recognized only at the time of surgical intervention.

Rare forms of isolation of the subclavian artery: echocardiographic diagnosis and surgical considerations.

Isolation of the subclavian artery is an unusual anomaly in which the subclavian artery arises not from the aortic arch but from a pulmonary artery via an arterial duct. Such isolation most often occurs with a right aortic arch, and in lesions frequently associated with a right arch, such as tetralogy of Fallot. Since 1994, we have undertaken surgery in four young infants with isolated subclavian arteries and unusual associated anomalies, including one with atrioventricular septal defect and common valvar orifice, two with interruption of a left aortic arch and one with interruption of a right aortic arch. In both patients with interrupted left arch, the isolated subclavian artery was diagnosed preoperatively by echocardiography. We emphasize the significant surgical issues.

Repair of congenital tricuspid valve abnormalities with artificial chordae tendineae.

BACKGROUND: Congenital abnormalities of the tricuspid valve, including Ebstein's malformation, dysplasia, straddling, and those found in pulmonary atresia with intact septum and congenitally corrected transposition, are an uncommon cause of tricuspid regurgitation. Congenital tricuspid valve anomalies are found as a spectrum of disease in which both the leaflets and the subvalvar apparatus are often involved. Tricuspid valve repair is complicated in such patients because the chordae tendineae are often abnormally short and thick. Replacement or augmentation of chordae tendineae has proved to be a useful component of mitral valve repair. In the present report, we describe the techniques and results of chordal augmentation in the repair of congenital tricuspid valve abnormalities. METHODS: Since July 1992, tricuspid valve repair has been performed in 5 children with severe tricuspid regurgitation secondary to congenital abnormalities of the tricuspid valve with significant chordal pathology. As a component of the repair, chordal replacement or augmentation was performed using expanded polytetrafluoroethylene suture. RESULTS: Intraoperative and postoperative echocardiographic assessment showed good mobility of the tricuspid valve leaflets and trivial to mild tricuspid regurgitation. There were no complications and no early or late mortality. At follow-up of 34 to 60 months (median, 49 months), tricuspid valve function has remained excellent in 4 of the 5 patients. In the remaining patient, progressive regurgitation of the right ventricle to pulmonary artery allograft conduit has led to right ventricular dilatation, with a secondary increase in tricuspid regurgitation from trivial to moderate. CONCLUSIONS: Chordal replacement or augmentation with expanded polytetrafluoroethylene suture is a useful technique in the repair of congenitally dysplastic tricuspid valves with abnormal chordal structures.

Echocardiographic hemodynamic and morphometric predictors of survival after two-ventricle repair in infants with critical aortic stenosis.

OBJECTIVES: The purpose of this study was to identify echocardiographic hemodynamic and morphometric factors that would predict which infants with critical aortic stenosis could undergo relief of left ventricular outflow obstruction as opposed to the Norwood procedure. BACKGROUND: Echocardiographic predictors of survival in infants with critical aortic stenosis after two-ventricle repair have been mainly limited to morphometric factors, which have limitations. Echocardiographic hemodynamic predictors of survival in these patients have not previously been studied. METHODS: Doppler color flow mapping and pulsed Doppler techniques were used to obtain hemodynamic measurements of flow in the ascending, transverse and descending aorta, the ductus arteriosus, and across the aortic and mitral valves in infants with critical aortic stenosis. Morphometric measurements of the left heart structures were obtained, and comparisons were made between survivors and nonsurvivors for the hemodynamic and morphometric factors. RESULTS: Twenty-eight infants (mean age 1 +/- .6 days, mean weight 3.6 +/- .6 kg) with critical aortic stenosis were evaluated. Nineteen had a two-ventricle repair initially attempted, and nine had a Norwood operation. Among the patients with a two-ventricle repair, the hemodynamic factors associated with survival after two-ventricle repair included predominant or total antegrade flow in the ascending (p < 0.01) and transverse aorta (p < 0.05). Aortic valve gradient, mitral valve inflow and direction of flow in the ductus arteriosus and descending aorta were unrelated to outcome. The morphometric factors associated with survival after two-ventricle repair included the indexed aortic annulus (p < 0.0002), aortic root (p < 0.003), ascending aorta (p < 0.008) and left ventricular long-axis length (p < 0.01). Left ventricular volume, mass, ejection fraction and mitral valve area were not related to outcome after two-ventricle repair. CONCLUSIONS: In infants with critical aortic stenosis, predominant or total antegrade flow in the ascending and transverse aorta was associated with survival after two-ventricle repair. Determination of a one- versus two-ventricle repair remains a complex issue in infants with critical aortic stenosis. In addition to established morphometric predictors, hemodynamic information on the direction of flow in the aorta may help to define candidates for the Norwood operation.

Geometric mismatch of pulmonary and aortic anuli in children undergoing the Ross procedure: implications for surgical management and autograft valve function.

BACKGROUND: There is often substantial mismatch between the diameters of the pulmonary and aortic anuli in young patients with systemic outflow tract disease. To implant the autologous pulmonary valve in the aortic position under such circumstances, it is necessary to adapt the geometry of the systemic outflow tract. The effects of such adaptations on autograft function in children are not well known. METHODS: To determine factors predictive of autograft regurgitation, we analyzed 41 cases of children who have undergone the Ross procedure. The diameter of the pulmonary valve was greater (by at least 3 mm) than that of the aortic valve in 20 cases, equal (within 2 mm) in 12 cases, and less (by at least 3 mm) in nine cases, with differences ranging from +10 to -12 mm. In 12 patients with a larger pulmonary anulus, aortoventriculoplasty was used to correct the mismatch. In patients with a larger aortic anulus, the mismatch was corrected by gradual adjustment along the circumference of the autograft, rather than by tailoring of the native aortic anulus. RESULTS: At follow-up (median 31 months), two patients had undergone reoperation on the neoaortic valve for moderate regurgitation. In the remaining 38 cases, autograft regurgitation was as follows: none or trivial in 30, mild in seven, and moderate in one. There was no correlation between regurgitation and age, geometric mismatch, or previous or concurrent procedures. CONCLUSIONS: Subtle technical factors that may result in distortion of the valve complex are probably more important determinants of autograft regurgitation than are indication for repair, geometric mismatch, or previous or concomitant outflow tract procedures. Significant mismatch of the semilunar anuli is not a contraindication to the Ross procedure in children.

Atrioventricular valve function after single patch repair of complete atrioventricular septal defect in infancy: how early should repair be attempted?

BACKGROUND: Though repair of complete atrioventricular septal defect in infancy has become routine at most centers, it is not unusual for very young infants to be managed medically because of concerns about the fragility of the atrioventricular valve tissue. METHODS: Since July 1992, seventy-two infants have undergone primary repair of complete atrioventricular septal defects at a median age of 3.9 months (40% < 3 months). A single-patch technique was used in all patients. The cleft was closed completely in 61 patients and partially (n = 10) or not at all (n = 1) in select patients at risk for valve stenosis. Left atrioventricular valve annuloplasty was performed in 18 patients. On the basis of transesophageal echocardiographic findings, 10 patients were returned to bypass for revision of the valve repair. RESULTS: There was one early death in a patient with single left papillary muscle, no early reoperations, and no new permanent arrhythmias. Only three patients had moderate left atrioventricular valve regurgitation at discharge. During a median follow-up of 24 months, there was one late death and five reoperations for left atrioventricular valve regurgitation (n = 2) and/or systemic outflow obstruction (n = 4). Follow-up left atrioventricular valve regurgitation was moderate in three patients, mild in 14, and none/trace in 54. Age had no relation to postoperative atrioventricular valve regurgitation, death, or reoperation. CONCLUSIONS: Despite concerns about fragility of valve tissue in very young patients, excellent results can be achieved with meticulous techniques. From neonates to older infants, age at repair does not influence outcome or valve function.