Factors affecting longevity of homograft valves used in right ventricular outflow tract reconstruction for congenital heart disease.

BACKGROUND: Few studies have explored the long-term function of cryopreserved homograft valves used for reconstruction of the right ventricular tract (RVOT) in patients with congenital heart disease. METHODS AND RESULTS: Among 205 patients receiving cryopreserved homografts for reconstruction of the RVOT between November 1985 and April 1999, the outcome of 220 homografts in 183 operative survivors was analyzed. There were 150 pulmonary and 70 aortic homografts used. Median age at implantation was 4.4 years (mean 6.9+/-7.6 years, range 3 days to 48 years). End points included (1) patient survival, (2) homograft failure (valve explant or late death), and (3) homograft dysfunction (homograft insufficiency or homograft stenosis). Survival was 88% at 10 years. Freedom from homograft failure was 74+/-4% at 5 years and 54+/-7% at 10 years. Univariable analysis identified younger age, longer donor warm ischemic time, valve Z: value <2, and previous procedure as risk factors for homograft failure and dysfunction. Aortic homograft type and extracardiac operative technique predicted homograft failure but not dysfunction. For patients

Doppler assessment of pulmonary artery flow patterns and ventricular function after the Fontan operation.

To assess the relation between ventricular systolic and diastolic function and pulmonary artery (PA) flow patterns after the Fontan operation, 15 postoperative patients were prospectively evaluated with echocardiography. Blood flow velocities in the PA were recorded with pulsed Doppler echocardiography. Ejection fraction was measured by 2-dimensional echocardiography using Simpson's rule. Indexes of diastolic function were measured from the systemic atrioventricular valve inflow Doppler and included peak E and A velocities, peak filling rate normalized for stroke volume, the fractions of filling in early and late diastole (E and A area fractions), and the E/A velocity and area ratios. Compared with 15 age-matched control subjects, the 15 patients who had undergone the Fontan procedure had decreased peak E velocity (0.65 +/- 0.20 vs 0.87 +/- 0.10 m/s), decreased E/A velocity ratio (1.29 +/- 0.23 vs 1.98 +/- 0.46), decreased normalized peak filling rate (6.09 +/- 0.90 vs 6.81 +/- 0.83 s-1), decreased E area fraction (0.63 +/- 0.09 vs 0.72 +/- 0.07), increased A area fraction (0.37 +/- 0.07 vs 0.24 +/- 0.06), and decreased E/A area ratio (1.77 +/- 0.45 vs 3.33 +/- 1.15) (p less than 0.05). These diastolic filling abnormalities are consistent with impaired ventricular relaxation and decreased early diastolic transvalvular pressure gradient. PA Doppler recordings showed 2 distinct patterns of flow. Pattern I, observed in 9 patients, showed biphasic forward flow with peak velocities in mid to late systole and mid-diastole. Pattern II, observed in the remaining 6 patients, showed decreased systolic forward flow, a late systolic to early diastolic flow reversal, and delayed onset of diastolic forward flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Home surveillance program prevents interstage mortality after the Norwood procedure.

OBJECTIVE: To determine whether early identification of physiologic variances associated with interstage death would reduce mortality, we developed a home surveillance program. METHODS: Patients discharged before initiation of home surveillance (group A, n = 63) were compared with patients discharged with an infant scale and pulse oximeter (group B, n = 24). Parents maintained a daily log of weight and arterial oxygen saturation according to pulse oximetry and were instructed to contact their physician in case of an arterial oxygen saturation less than 70% according to pulse oximetry, an acute weight loss of more than 30 g in 24 hours, or failure to gain at least 20 g during a 3-day period. RESULTS: Interstage mortality among infants surviving to discharge was 15.8% (n = 9/57) in group A and 0% (n = 0/24) in group B (P =.039). Surveillance criteria were breached for 13 of 24 group B patients: 12 patients with decreased arterial oxygen saturation according to pulse oximetry with or without poor weight gain and 1 patient with poor weight gain alone. These 13 patients underwent bidirectional superior cavopulmonary connection (stage 2 palliation) at an earlier age, 3.7 +/- 1.1 months of age versus 5.2 +/- 2.0 months for patients with an uncomplicated interstage course (P =.028). A growth curve was generated and showed reduced growth velocity between 4 and 5 months of age, with a plateau in growth beyond 5 months of age. CONCLUSION: Daily home surveillance of arterial oxygen saturation according to pulse oximetry and weight selected patients at increased risk of interstage death, permitting timely intervention, primarily with early stage 2 palliation, and was associated with improved interstage survival. Diminished growth identified 4 to 5 months after the Norwood procedure brings into question the value of delaying stage 2 palliation beyond 5 months of age.

Aprotinin improves outcome of single-ventricle palliation.

BACKGROUND: Elevation of pulmonary vascular resistance as a consequence of cardiopulmonary bypass may lead to failure of single-ventricle palliation. We reviewed our experience with aprotinin, a nonspecific serine protease inhibitor, to determine whether it could ameliorate the inflammatory effects of cardiopulmonary bypass and improve outcome of single-ventricle palliation. METHODS: Forty-six consecutive patients undergoing single-ventricle palliation using cardiopulmonary bypass were reviewed retrospectively. Aprotinin was used in 8 of 30 bidirectional cavopulmonary shunt and 10 of 16 Fontan procedures. RESULTS: Aprotinin use was associated with a decrease in the early postoperative transpulmonary gradient among patients undergoing Fontan and bidirectional cavopulmonary shunt procedures. The bidirectional cavopulmonary shunt aprotinin group had a higher oxygen saturation and a decrease in quantity and duration of thoracic drainage. Among patients receiving aprotinin there were no episodes of mediastinitis, thrombus formation, or renal failure. CONCLUSIONS: Aprotinin use in single-ventricle palliation was associated with decreased transpulmonary gradient and increased oxygen saturation consistent with decreased pulmonary vascular resistance. This retrospective study suggests that aprotinin has a favorable impact on the early postoperative course of single-ventricle palliation.

Twenty-year experience with repair of complete atrioventricular septal defects.

BACKGROUND: To determine factors predicting mortality and morbidity after repair of complete atrioventricular septal defect, we retrospectively analyzed preoperative, operative, and postrepair factors on the outcome of 115 consecutive complete atrioventricular septal defect repairs at The Children's Hospital of Wisconsin between January 1974 and December 1993. METHODS: For the entire experience the operative mortality was 13.9% (16 patients). During the most recent era, January 1988 to December 1993, operative mortality was 3.6% (2 of 55 patients). This was significantly improved from the two previous eras, January 1974 to December 1980, 28% (7 of 25) and January 1981 to December 1987, 20% (7 of 35 patients) (p = 0.02). There were seven late deaths; 10-year actuarial survival, including operative mortality was 81%. Age at complete repair decreased; before 1982 all patients were more than 12 months of age, whereas after 1982 64% (56 of 88 patients) were 12 months of age or less. RESULTS: Moderate or severe preoperative left atrioventricular valve regurgitation was not a risk factor for operative mortality. For operative survivors with moderate to severe preoperative left atrioventricular valve regurgitation (n = 17), late postoperative left atrioventricular valve regurgitation (follow-up data available on 15 patients) was significantly reduced (severe = 1, moderate = 5, mild = 9; p = 0.007). CONCLUSIONS: Early mortality was predicted by the era of surgical repair. Conversion to routine repair during infancy was achieved with a simultaneous decrease in operative mortality. For patients with moderate to severe preoperative left atrioventricular valve regurgitation, significant improvement in the degree of left atrioventricular valve regurgitation can be expected without an increase in operative or late mortality or morbidity.

Transesophageal echocardiographic in total anomalous pulmonary venous drainage: hypotension caused by compression of the pulmonary venous confluence during probe passage.

Compression of vascular and airway structures can complicate transducer passage and manipulation during transesophageal echocardiography. This case describes hemodynamic compromise caused by compression of the posterior pulmonary venous confluence by a transesophageal echocardiography probe during intraoperative evaluation in an infant with supracardiac total anomalous pulmonary venous drainage. Careful hemodynamic and airway monitoring during transesophageal echocardiography is required in all patients, particularly during initial probe insertion and esophageal passage.

Anomalous origin of the right coronary artery from the left sinus of valsalva: transthoracic echocardiographic diagnosis.

Anomalous origin of the right coronary artery from the left sinus of Valsalva is a rare congenital defect that can be difficult to diagnose by echocardiography. We describe an infant with a ventricular septal defect that was diagnosed prospectively by transthoracic echocardiography as an anomalous origin of the right coronary artery from the left sinus of Valsalva. Subcostal imaging and Doppler color flow mapping were instrumental in the echocardiographic diagnosis of this unusual coronary abnormality.

Advances in echocardiographic diagnostic modalities for the pediatrician.

Two-dimensional Doppler echocardiography has become the primary diagnostic tool in the assessment of infants and children with congenital and acquired heart disease. Over the past 10 years, specialized echocardiographic techniques have also become critical components in the evaluation and treatment of these patients. Using fetal echocardiography enables us to image the heart early in gestation and have begun to understand those lesions that can develop and progress in utero. Transesophageal echocardiography has allowed you to image the patient with congenital heart disease during repair in the operating room and in the cardiac catheterization laboratory so that adequacy of the repair can be assess and any residual lesions addressed immediately. Both of these specialized techniques are discussed in detail, with a brief overview at the three-dimensional future of echocardiography in the pediatric patient.

Advances in the care of children with heart disease.

As we enter the next millennium, we are encouraged by the progress that has been made in the care of neonates, infants, and children with heart disease. Surgical repair can be offered at an earlier age with excellent results. Diseases that were uniformly fatal in the past have improved outcomes. Research continues in the area of interventional devices such that surgical repair might be eliminated or delayed. We continue to look forward to advances in the next several years that will allow for future improvement in outcome, better quality-of-life and better long-term results.

Intraoperative rhythm analysis using pulmonary venous Doppler: importance of atrioventricular interval.

Inappropriate timing or duration of the atrioventricular (AV) interval with DDD pacing can lead to hemodynamic compromise. Intraoperative pulmonary venous Doppler interrogation by transesophageal echocardiography can be a valuable tool to assess subtle rhythm abnormalities that may go unnoticed by electrocardiogram and hemodynamic monitoring. We describe a dramatic example of hemodynamic improvement following pacemaker adjustment after pulmonary venous Doppler identified an inappropriately short AV interval.

Natural history of apical left ventricular to aortic conduits in pediatric patients.

To determine the long-term efficacy of apical left ventricular to aortic conduits in palliating complex left ventricular outflow obstruction, we reviewed our entire experience of 20 pediatric patients who underwent placement of a composite porcine valve-bearing conduit from the left ventricular apex to the aorta from November 1977 to April 1987. There were two early postoperative deaths, both in infants less than 2 months of age at the time of surgery. The remaining 18 patients had successful conduit placement with significant relief of the left ventricular outflow obstruction. Conduits have remained functional from 3 to greater than 9 years after initial placement. Long-term maintenance of a well-functioning conduit was limited by conduit heterograft valve dysfunction secondary to degeneration and calcification, with a 3-year conduit survival of 80 +/- 9% and a 7-year survival of 52 +/- 11%. Clinical identification of conduit valve insufficiency was found to be a useful early indicator of impending conduit failure, frequently preceding other signs and symptoms of conduit valve dysfunction. Eight patients required reoperation for conduit failure, and there were two late deaths associated with conduit valve dysfunction. Other long-term complications were rare. No thromboembolic events occurred despite avoidance of anticoagulant therapy, and there were no documented episodes of bacterial endocarditis. Thus, apical aortic conduit placement is an effective surgical technique for intermediate palliation of complex left ventricular outflow obstruction and may be useful in selected pediatric patients as a staging procedure before left ventricular outflow reconstruction.

Experience with a DICOM-compatible digital pediatric echocardiography laboratory.

A digital pediatric echocardiography laboratory, without videotape redundancy was established at Children's Hospital of Wisconsin in December 1998. To characterize the experience, 1198 consecutive patient studies were reviewed-50% from the first 2 months after establishing the digital protocol and 50% from the last 2 months available. Each study was stored using a protocol that was based on capture of single beat clips of relevant two-dimensional/color Doppler imaging and static frame spectral Doppler tracings. Studies were digitally compressed using a DICOM-compatible JPEG algorithm at 20:1 and edited with deletions of redundant clips to minimize archival storage needs. Study quality was uniformly excellent, and no errors were attributable to the digital protocol or compression-related loss of information. The average study required 21.5 +/- 11.4 MB of storage space with 35.4 +/- 12.3 total clips/study captured. Studies reviewed from the earlier experience were not significantly larger (23.6 +/- 14 vs 19.7 +/- 8.1 MB, 35.6 +/- 12.5 vs 35.2 +/- 12 clips) than those done recently. Studies in patients with isolated ventricular septal defect used comparable storage (23.7 +/- 8.9 MB, 42.8 +/- 11.5 clips) to that of the group as a whole. More complex congenital heart disease studies were slightly larger-tetralogy of Fallot (28.2 +/- 19.5 MB, 43.4 +/- 13.9 clips), transposition of the great arteries (30.6 +/- 17.4 MB, 40.3 +/- 16.7 clips), and single ventricle (29.7 +/- 19.6 MB, 39.9 +/- 12 clips)--although this trend was not significant. This study suggests that digital pediatric echo is feasible using a DICOM-compatible protocol with maintenance of diagnostic integrity despite compression of study size to allow rapid archival storage and retrieval.

Aortoventriculoplasty in infants and children.

BACKGROUND: When aortic valve replacement is required in infants or small children with complex left ventricular outflow tract obstruction (LVOTO) or aortic incompetence (AI), the diameter of the annulus may limit the size of the prosthesis that can be safely inserted, and aortoventriculoplasty (AVP) may be required. To assess the results of this procedure in the pediatric age group, we reviewed our results in 19 patients who underwent AVP from May 1986 to April 1991. METHODS AND RESULTS: Patient age ranged from 1 day to 18 years (mean, 5.9 years), with six patients < 2 years of age and 13 patients younger than 5 years. Operative indications included complex LVOTO after aortic valvotomy and/or subaortic resection (six), severe AI after valvotomy or aortic valve replacement (four), severe AI with bacterial endocarditis (one), truncus arteriosus with truncal insufficiency (three), failure of an apical-aortic conduit (three), and combined aortic stenosis and mitral stenosis (two). In all patients, valve insertion was performed after patch enlargement of the annulus and septum. Associated procedures included coronary artery reimplantation in five patients and mitral valve replacement in two. Mechanical valve prostheses were used in 15 patients and allografts in four. There were three hospital deaths (16%; 70% confidence limit, 9-26%), two in patients with severe pulmonary vascular disease, and no late deaths. Actuarial survival was 84 +/- 8% at 1 month and beyond (mean follow-up, 2.5 years). Complications have included complete heart block (one), residual ventricular septal defect (one), and early postoperative peripheral embolus (one). No late thromboembolic events have occurred. No patient has clinical or echocardiographic evidence of significant residual LVOTO or AI. CONCLUSIONS: These data indicate that AVP may be performed at low risk and that it is an effective procedure for complex LVOTO or AI in infants and small children.

Prospective identification of anomalous origin of left coronary artery from the right sinus of valsalva using transthoracic echocardiography: importance of color Doppler flow mapping.

Four cases are discussed in which anomalous origin of the left coronary artery from the right sinus of Valsalva was identified prospectively by transthoracic echocardiography when the anomalous coronary passed between the great arteries. Color Doppler flow mapping was a critical component in identifying the anomalous coronary, particularly when the proximal course of the left main coronary was intramural.

Does an additional source of pulmonary blood flow alter outcome after a bidirectional cavopulmonary shunt?

BACKGROUND: The bidirectional cavopulmonary shunt has become an important intermediate step in the treatment of pediatric patients with single ventricle physiology who are ultimately destined for palliative surgery. We wanted to know whether there would be risks or benefits if an additional source of pulmonary blood flow was left after a bidirectional cavopulmonary shunt. METHODS AND RESULTS: We retrospectively reviewed the medical and surgical records of all patients who underwent a bidirectional cavopulmonary shunt at the Children's Hospital of Wisconsin between January 1991 and December 1993. A total of 43 patients were identified. Anatomic diagnoses included double inlet left ventricle (14 patients), tricuspid atresia (8 patients), pulmonary atresia with intact septum (6 patients), single right ventricle (5 patients), hypoplastic left heart (3 patients), unbalanced atrioventricular septal defect (3 patients), and other complex lesions (4 patients). We then divided the patients into two groups for purposes of analysis. Group 1 had only the cavopulmonary shunt as a source of pulmonary flow (22 patients); group 2 had an additional source of pulmonary flow (21 patients). Patient age at the time of cavopulmonary shunt ranged from 6 months to 12 years, with group 1 patients being younger (31 versus 45 months, P = .05). Group 2 patients had higher postoperative central venous pressures (17.8 versus 14.1 mm Hg, P < .001) and oxygen saturations (86% versus 81%, P < .001) than did group 1 patients. There was no statistical difference between groups in the number of chest tube days or hospital days. There was 1 early death in group 1 related to severe ventricular dysfunction and 1 late death in group 2 related to sepsis. Five patients in group 2 were readmitted to the hospital for drainage of a large chylothorax compared with none in group 1 (P < .02). CONCLUSIONS: We conclude that patients with an additional source of pulmonary blood flow after bidirectional cavopulmonary shunt have higher postoperative central venous pressures, have higher oxygen saturations, and are at risk for the late development of a chylothorax.