Factors related to pleural effusions after Fontan procedure in the era of fenestration

BACKGROUND

Significant pleural effusions after the Fontan operation prolong hospital stay, may increase the risk of infection, and may necessitate a pleurodesis procedure.

METHODS AND RESULTS

From February 1991 to April 2000, 98 consecutive patients under the age of 18 years underwent the fenestrated Fontan procedure at Children's Hospital of Wisconsin. Ninety-four patients who survived at least 30 days after surgery were retrospectively evaluated for the following factors: age, ventricular morphology (right single ventricle, left single ventricle [RV/LV]), fenestration open (FO) or closed (FC) at end of operation, intracardiac Fontan (IF) or extracardiac Fontan (EF), days with chest tube output per day >5, 10, and/or 20 mL. kg(-1). d(-1) (CTO5, CTO10, and CTO20, respectively), need for pleurodesis, length of hospital stay (LOS), operation during winter respiratory viral season of November through March (ReVS+, ReVS-), and pre-Fontan mean pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR). In univariate analysis, the ReVS+ patients had prolonged LOS, greater chest tube output, and more pleurodesis (P<0.05), and PAP was related to CTO5 and CTO10 but not to CTO20 or LOS. No significant differences were found in LOS, CTO5, CTO10, CTO20, and need for pleurodesis between patients in RV/LV, FO/FC, IF/EF, or PVR groups. Patients <4 years of age had more instances of CTO20 (P<0.05). When we used ordinary least squares regression analysis with age, FO or FC, RV or LV, PAP, and ReVS+ or ReVS- to predict each of CTO5, CTO10, CTO20, and LOS, only ReVS+ or ReVS- and age were statistically significant in all models.

CONCLUSIONS

Use of the Fontan procedure during the respiratory viral season appeared to be related to significant, prolonged pleural effusions and longer hospitalizations.

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 </=1 year of age, valve type did not predict failure or dysfunction. Multivariable analysis identified younger age and longer donor warm ischemic time as risk factors for homograft failure and dysfunction, whereas, Z: value <2 and aortic valve type predicted homograft valve failure.

CONCLUSIONS

Homograft valves used for RVOT reconstruction provide effective intermediate palliation with excellent late survival. Factors that adversely affect graft longevity include younger age, longer donor warm ischemic time, smaller homograft size, use of aortic homograft in the older patient, and extracardiac operative technique.

Patients at risk for low systemic oxygen delivery after the Norwood procedure

BACKGROUND

Identification of patients at risk for inadequate systemic oxygen delivery following the Norwood procedure could allow for application of more intensive monitoring, provide for earlier intervention of decreased cardiac output, and result in improved outcome.

METHODS AND RESULTS

Superior vena cava saturation (SvO2) and arteriovenous oxygen content difference were prospectively monitored as indicators of systemic oxygen delivery and recorded hourly for the first 48 hours in 29 of 33 consecutive patients following the Norwood procedure. Risk factors were evaluated using multiple linear regression to determine their impact on SvO2 and arteriovenous oxygen content difference. Age less than 8 days, weight less than 2.5 kg, aortic atresia, and prolonged cardiopulmonary bypass time were risk factors for low SvO2 and wide arteriovenous oxygen content difference (p < 0.05). Phenoxybenzamine and increasing time after operation were associated with higher SvO2 and narrower arteriovenous oxygen content difference (p < 0.05). Thirty-day survival was 97% and hospital survival was 94%. The earliest death occurred on postoperative day 20. Survival to bidirectional cavopulmonary shunt was 77%. Preoperative mechanical ventilation was the only risk factor identified for late death.

CONCLUSIONS

Aortic atresia, low weight, younger age, and prolonged cardiopulmonary bypass, previously identified risk factors for mortality, were associated with decreased SvO2 and narrower arteriovenous oxygen content difference in the early postoperative period. The impact of this hemodynamic vulnerability on mortality was minimized by continuous SvO2 monitoring.

Left ventricular outflow obstruction

Patients with LVOT obstruction require lifelong follow-up because the obstruction may be progressive or recurrent. Several procedures are usually required, either by surgery or by interventional cardiac catheterization, to repair or palliate the obstructive lesion. The treatment of these patients continues to evolve, and, despite the complexity of these patients' lesions, the morbidity and mortality rates have decreased and are expected to decrease further in the future.

Phenoxybenzamine improves systemic oxygen delivery after the Norwood procedure

BACKGROUND

Achieving adequate systemic oxygen delivery after the Norwood procedure frequently is complicated by excessive pulmonary blood flow at the expense of systemic blood. We hypothesized that phenoxybenzamine could achieve a balanced circulation through reduction of systemic vascular resistance.

METHODS

In this prospective, nonrandomized study, oximetric catheters were placed in the superior vena cava for continuous monitoring of systemic venous oxygen saturation. Postoperative hemodynamic variables were compared between 7 control patients and 8 patients who received phenoxybenzamine.

RESULTS

The hospital survival rate was 93% (14 of 15 patients). Improvements in postoperative hemodynamics in the phenoxybenzamine group included a higher systemic venous oxygen saturation, a narrower arteriovenous oxygen content difference, a lower ratio of pulmonary to systemic flow, and a lower indexed systemic vascular resistance. In the phenoxybenzamine group, mean arterial blood pressure was related directly to systemic oxygen delivery, in contrast to the control group, where mean arterial pressure was related directly to indexed systemic vascular resistance and the ratio of pulmonary to systemic circulation.

CONCLUSIONS

Continuous postoperative monitoring of systemic venous oxygen saturation in a patient who has undergone the Norwood procedure provides early identification of low systemic oxygen delivery and an elevated ratio of pulmonary to systemic circulation. In this pilot study, phenoxybenzamine appeared to improve systemic oxygen delivery during the early postoperative period after the Norwood procedure. Further studies are indicated to confirm these results.

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.

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.

Follow-up of coil occlusion of patent ductus arteriosus

OBJECTIVE

We sought to determine the prevalence and fate of residual ductal shunting following coil occlusion of patent ductus arteriosus.

BACKGROUND

Although transcatheter coil occlusion of patent ductus arteriosus has gained popularity, few follow-up data have been reported.

METHODS

A review of 75 patients who underwent coil occlusion was performed. Residual shunting was investigated by Doppler echocardiography in follow-up. Angiograms were reviewed to obtain minimal ductal diameter and ductal angiographic type.

RESULTS

Residual shunts were found in 31 patients (41%) on the day of the procedure, and of these, spontaneous closure was noted in 17 (55%) at 2 weeks to 20 months of follow-up. Of the 75 patients studied, 5 (7%) required a second coil procedure, and 10 (13%) remained with persistent residual shunts at most recent follow-up. Actuarial analysis estimated a 6 +/- 5% prevalence of residual shunts 20 months after a single coil procedure and 3 +/- 3% after all coil procedures. Minimal ductal diameter was associated with immediate complete ductal occlusion by a single coil. These patients had significantly smaller (p = 0.003) minimal ductal diameters (1.2 +/- 0.7 mm) than those who required two coils during their initial procedure to achieve immediate occlusion (1.9 +/- 0.7 mm), those who required a second coil procedure (2.0 +/- 0.9 mm), those who had spontaneous closure of residual shunts (1.9 +/- 0.7 mm) and those with persistent residual shunts (2.0 +/- 0.9 mm). No association was identified between ductal angiographic type and outcome of coil occlusion. No late adverse clinical events of coil occlusion or evidence of recanalization was found.

CONCLUSIONS

Small residual shunts are common after coil embolization of patent ductus arteriosus, but most close spontaneously. Actuarial analysis estimates complete closure in 94% at 20 months, and reintervention was required in only 7% of patients.

Comparison of hospital charges for closure of patent ductus arteriosus by surgery and by transcatheter coil occlusion

Hospital charges for coil occlusion were significantly less than for surgical closure of patent ductus arteriosus, and were reduced over time as experience permitted refinement of the coil occlusion protocol. The expected hospital charges for closure by a coil occlusion strategy, including the charges for surgical closure in patients with failed coil occlusion, was less than the hospital charges for surgical closure strategy under any reasonable estimate of coil occlusion efficacy.

Balloon valvuloplasty for pulmonary valve stenosis

Balloon valvuloplasty for pulmonary valve stenosis by static dilation is the treatment of choice for the treatment of isolated valvular pulmonary stenosis in the infant, child, and adolescent. The procedure is also effective in neonates; however, the complications of the procedure are significantly higher and the efficacy is less. This article reviews the background, indications, technique, acute and long-term results, and complications of balloon valvuloplasty for pulmonary valve stenosis in the infant, child, and adolescent with pulmonary valve stenosis. The application of this technique in neonates with critical pulmonary stenosis or membranous pulmonary atresia with intact ventricular septum is also discussed. The determinants of a successful outcome in each group are addressed.

Determinants of successful balloon valvotomy in infants with critical pulmonary stenosis or membranous pulmonary atresia with intact ventricular septum

OBJECTIVES

This study reviewed our experience with percutaneous balloon valvotomy in infants with critical pulmonary stenosis or membranous pulmonary atresia with intact ventricular septum and defined the anatomic and hemodynamic characteristics of infants in whom this procedure is successful and provides definitive therapy.

BACKGROUND

Unlike children with valvular pulmonary stenosis, the follow-up of infants with critical pulmonary stenosis undergoing percutaneous balloon valvotomy is limited.

METHODS

Between December 1987 and August 1992, percutaneous balloon valvotomy was attempted in 12 infants with critical pulmonary stenosis (n = 10) or pulmonary atresia with intact ventricular septum (n = 2). Two outcome groups were identified: Group A patients are acyanotic, have mild residual pulmonary stenosis and have not required operation; Group B patients have required operation.

RESULTS

Of the 12 infants, 11 had a successful balloon valvotomy procedure. Group A patients (n = 7) have a residual gradient of 22 +/- 18.7 mm Hg (mean +/- SD) at follow-up of 3.2 years (range 1.2 to 5.0). In Group B (n = 5), operation was required for inability to cross the pulmonary valve (n = 1) or persistent severe hypoxemia for > or = 2 weeks after valvotomy (n = 4). Significant differences (p < or = 0.01) between the two groups (Group A vs. Group B) were identified in pulmonary valve annulus (Z value) 8.1 mm (-1.1) versus 5.5 mm (-3.4); tricuspid valve annulus (Z value) 14.0 mm (0.8) versus 8.8 mm (-1.8); right ventricular volume 65 versus 29 ml/m2; and Lewis index 10.9 versus 8.9.

CONCLUSIONS

Percutaneous balloon valvotomy is effective and likely to provide definitive therapy in infants with critical pulmonary stenosis or membranous pulmonary atresia with intact ventricular septum who have a tricuspid valve annulus > 11 mm, pulmonary valve annulus > or = 7 mm and right ventricular volume > 30 ml/m2.

Intraoperative and percutaneous stenting of congenital pulmonary artery and vein stenosis

BACKGROUND

Conventional surgical or balloon dilation therapy for pulmonary artery or vein stenosis has been unsatisfactory in many patients. Balloon-expandable stents offer a new form of treatment for these vascular stenoses and can be implanted percutaneously or intraoperatively.

METHODS AND RESULTS

Between July 1991 and October 1992, 20 balloon-expandable Palmaz stents (Johnson & Johnson) were implanted in 16 children at median age and weight of 3.0 years and 12.8 kg, respectively. Stent implantation was performed intraoperatively (n = 15) if the patient was less than 1 year of age or less than 10 kg in weight, in cases where limited vascular access precluded percutaneous implantation, or as an adjunct to other intracardiac surgery. Otherwise, percutaneous stenting was performed (n = 5). Vessels were tested for distensibility by dilation with balloon catheters or vascular sounds. Stents were implanted using angioplasty catheter balloons chosen to achieve desired vessel diameter and inflated to 4 to 17 atm. Acute hemodynamic and cineangiographic studies were performed in all patients immediately after the procedure to 2 months after stenting. After pulmonary artery stent implantation, mean pulmonary artery diameter increased from 5.6 to 11.5 mm (P = .001), with a decrease in mean systolic pressure gradients from 43 to 8.0 mm Hg (P = .005). Follow-up cardiac catheterization (mean, 8.7 months) in 3 patients revealed no restenosis, thrombosis, or aneurysm formation. In patients in whom pulmonary vein stents were implanted, mean pressure gradients fell from 11 to 0.3 mm Hg (P = .03), and mean pulmonary capillary wedge pressure fell from 17 to 6.3 mm Hg (P = .03) immediately after stenting. At 2- to 6-month follow-up, cardiac catheterization documented restenosis within the stent in 2 of 3 patients. The third patient died 2 months after stenting from presumed vein reocclusion.

CONCLUSIONS

When implanted intraoperatively or percutaneously, balloon-expandable endovascular stents have been efficacious in the treatment of pulmonary artery stenosis. Longer follow-up will be necessary to document the long-term effectiveness of pulmonary artery stenting. Preliminary data suggest that early restenosis is common after pulmonary vein stenting. The intraoperative approach extends stenting therapy to smaller children and to patients who have limited percutaneous access.