Compared fate of small-diameter Contegras and homografts in the pulmonary position.

OBJECTIVE: This study analyzes whether small-diameter Contegras behave in the same way as small-diameter homografts, when implanted for the first time in pulmonary position. METHODS: Small-diameter conduits include 12 and 14 mm Contegras and 8-14 mm homografts. Graft dysfunction is defined as right ventricular outflow tract obstruction with peak echo-Doppler gradient>40 mmHg, or grade III/IV graft regurgitation. Graft failure is defined as need for conduit replacement or need for catheter or surgical reintervention. Thirty-eight patients who received small Contegras (n=25) and small homografts (n=13) from October 2002 to end December 2006 were studied. The most frequent indication was pulmonary atresia and ventricular septal defect (n=20; 10 associated with major aorto-pulmonary collateral arteries), followed by truncus arteriosus (n=12). Most patients' characteristics were comparable except that recipients of homografts were smaller (p for body area=0.014). Survival, freedom from graft dysfunction, failure and explantation were estimated by the Kaplan-Meier method. The log-rank test was used to compare outcomes. RESULTS: There were three early and four late deaths. No death was graft related. Survival was 80+/-8.2% for patients with Contegras and 77+/-11.7% for those with allografts: p=0.82. Mean follow-up duration is 22+/-16 months. Freedom from dysfunction for Contegras conduits decreased in the first 6 months and stabilized at 58+/-11% from month 14. For homografts it decreased only 1 year after implantation, down to 35+/-19.7% from month 31: p=0.61. Freedom from Contegras failure diminished the first 16 months to level out at 57+/-13%. No homograft failed the first 2 years. With a p-value of 0.14, homografts tended to fail less frequently. Five grafts were explanted. Freedom from explantation was similar (p=0.98): 90+/-6.7% for Contegras and 75+/-21.6% for homografts at year 3. CONCLUSION: In the first 4 years after pulmonary implantation of small-diameter Contegras and homografts, the fate of both conduits was statistically similar, in spite of different behavior. As Contegras is 'off-the-shelf' available, it constitutes a sound alternative to homograft for right ventricular outflow tract reconstruction in neonates and infants.

Twenty years experience of surgical aortic valvotomy for critical aortic stenosis in early infancy.

OBJECTIVE: To examine early and long-term results of surgical aortic valvotomy in neonates and infants aged less than 3 months. METHODS: A review of all 34 neonates (n=26) and young infants (n=8) aged 1-62 days undergoing primary open valvotomy for aortic valve stenosis between 1983 and 2003 was carried out. Associated major cardiac anomalies were endocardial fibroelastasis (n=8), aortic coarctation (n=3), subvalvular aortic stenosis (n=2), and ventricular septal defect (n=1). Risk factors for early mortality were estimated. Current information was available for 31 patients for a follow-up of 115+/-67 months. Kaplan-Meier method was used to estimate freedom from reintervention. RESULTS: Two neonates died early: operative mortality of 6% (2/34). Risk factors for early mortality were associated endocardial fibroelastosis, monocuspid aortic valve and impaired left ventricular function. No patient died late. Seven patients needed reintervention for re-aortic stenosis (n=5) or aortic insufficiency (n=2), i.e., re-valvotomy (n=3), valve replacement (n=2), Ross procedure (n=1), and balloon valvuloplasty (n=1). Freedom from reintervention was 85.1+/-6.9%, 78.0+/-9.35%, and 53.5+/-15.9% at 5, 10, and 15 years, respectively. CONCLUSIONS: Primary surgical aortic valvotomy in early infancy carries a low early and late mortality, a low occurrence of significant aortic regurgitation and a low early recurrence of aortic stenosis. In great majority of cases, reintervention can be delayed to allow implantation of an adult-sized prosthesis, when required.

Optimal pulmonary to systemic blood flow ratio for best hemodynamic status and outcome early after Norwood operation.

OBJECTIVE: Imbalances of pulmonary to systemic blood flow ratio (Q(p)/Q(s)) compounded with inadequate systemic oxygen delivery correlate with mortality after first-stage Norwood palliation of hypoplastic left heart syndrome. Mathematical models suggest that maximal systemic oxygen delivery occurs with Q(p)/Q(s) of less than 1. Whether this applies to clinical practice is unclear. This study evaluates the level of Q(p)/Q(s) that correlates with best hemodynamic status in the first 48 postoperative hours. METHODS: Hemodynamic data of 25 consecutive patients who underwent Norwood procedure from October 2002 to January 2005 were retrospectively analyzed. Data included, in particular, systemic venous and arterial oxygen saturation (SvO(2) and SaO(2), respectively), Q(p)/Q(s), lactate levels, and doses of required inotropes. Parameters were recorded 3 hourly. Data were assigned to three groups according to their corresponding Q(p)/Q(s): Groups 1, 2, and 3 for Q(p)/Q(s)< or =1, Q(p)/Q(s) between 1 and 2, and Q(p)/Q(s)> or =2, respectively. Thereafter, independent t-test or Fisher's exact test was used to reveal significant differences. Q(p)/Q(s) ratios and lactate levels were compared in hospital survivors and non-survivors. RESULTS: Out of 343 samples, 110, 184, and 49 were assigned to groups 1, 2, and 3, respectively. Group 1 (Q(p)/Q(s)< or =1) was characterized by lower SaO(2) (p<0.001) with similar SvO(2) (p=0.3 and p=0.5) and, therefore, higher systemic oxygen delivery (arteriovenous oxygen saturation difference, p<0.001; oxygen excess factor, p<0.001) compared to groups 2 and 3. However, lower mean arterial pressure (p=0.07 and p<0.001), higher lactate levels (p=0.009 and p=0.01), and norepinephrine doses (p=0.006 and p<0.001) highlighted worse hemodynamics. The best hemodynamic status corresponded to group 2. Q(p)/Q(s) remained above 1 in 21 survivors and was, most of the times, below 1 in four patients who died. Lactate levels were almost always above 4 mmol/l or increasing in non-survivors. CONCLUSIONS: Maximum oxygen delivery after Norwood operation occurs at Q(p)/Q(s) of less than 1. However, optimal hemodynamic status and end-organ function and higher survival correlates with Q(p)/Q(s) between 1 and 2. Thus, Q(p)/Q(s) should be targeted at 1.5 for improved course early after first-stage Norwood palliation.

Results of arterial switch operation for primary total correction of the Taussig-Bing anomaly.

BACKGROUND: This study evaluates the results of the arterial switch operation for early total repair of double-outlet right ventricle with subpulmonary ventricular septal defect (the Taussig-Bing heart). METHODS: From 1986 through April 2003, 27 patients with Taussig-Bing anomaly underwent arterial switch operation. Twenty patients were neonates (n = 11) or infants younger than 3 months (n = 9). Obstruction of aortic arch (n = 19) or subaortic right ventricular outflow tract obstruction (n = 20) and unusual coronary artery patterns (n = 19) were common. Total correction as a single procedure was performed in 21 patients. Events are depicted by Kaplan-Meier curves. RESULTS: There was 1 patient hospital death at 2 months after repair. One patient died late that was not cardiac related. Survival was 92% +/- 6% at 8 months and remained constant thereafter. Four patients underwent reoperation (1 for residual aortic arch obstruction and 3 for subvalvular and valvular pulmonary stenosis). Freedom from reoperation decreased to stabilize at 83% +/- 8% after 2 years. The risk to have right ventricular outflow tract obstruction develop was 33% +/- 10% at 1 year, increasing slowly and leveling out at 57% +/- 12% at year 5 and thereafter. Statistical analysis revealed no significant risk factor for death or need for reoperation. CONCLUSIONS: The Taussig-Bing anomaly should be corrected in the neonatal period or in early infancy by arterial switch operation, closure of the ventricular septal defect, and simultaneous correction of associated cardiovascular anomalies as a one-stage procedure. Right ventricular outflow tract obstruction often complicates the postoperative course and is the main cause for reintervention.

Improved hemodynamics and outcome after modified Norwood operation on the beating heart.

BACKGROUND: Recently introduced cardiopulmonary bypass techniques to avoid circulatory arrest were proposed to improve organ function of the modified Norwood operation for hypoplastic left heart syndrome. This study compares postoperative hemodynamics and survival in patients who underwent Norwood procedure on the beating heart to those operated on with cardioplegic cardiac arrest. METHODS: Between October 2002 and January 2005, 26 consecutive patients aged 4 to 275 days (median, 9 days) and weighing 2.9 to 4.4 kg (median, 3.4 kg) underwent Norwood palliation: 13 with continuous coronary and systemic perfusion (group 1), and 13 with only continuous systemic perfusion but arrested heart (group 2). Standard hemodynamic measurements, lactate levels, arterial and superior vena cava oxygen saturations, and inotropic agents required for postoperative hours 0, 6, 12, 18, 24, and 48 were retrospectively analyzed. For univariate comparison of different variables, chi2 test, Fisher's exact test, or Student's t test was used as appropriate. RESULTS: In group 1 significantly higher mean arterial pressure (53 +/- 0.8 versus 50 +/- 1.2 mm Hg; p = 0.04), higher central oxygen saturation (54% +/- 1.1% versus 50% +/- 1.5%; p = 0.03), higher urinary output (5.3 +/- 0.4 versus 4.4 +/- 0.4 mL.kg(-1).h(-1); p = 0.09), lower lactate levels (2.4 +/- 0.1 versus 4.1 +/- 0.6 mmol/L; p = 0.009) with lower doses of norepinephrine (0.03 +/- 0.004 versus 0.14 +/- 0.03 microg.kg(-1).min(-1); p = 0.002) were recognized. Hospital mortality was 0% in group 1 and 38.5% (5 of 13) in group 2 (p = 0.04). Univariate analysis revealed mortality to be also correlated with preoperative intubation (p = 0.02) and the use of preoperative inotropic agents (p = 0.03). CONCLUSIONS: Avoidance of cardiac arrest by means of continuous coronary perfusion in addition to continuous systemic perfusion significantly improves postoperative hemodynamic performance and thus helps to reduce hospital mortality after the modified Norwood procedure.

Comprehensive Aristotle score: implications for the Norwood procedure.

BACKGROUND: Aristotle score is emerging as a reliable tool to measure surgical performance. We estimated the comprehensive Aristotle score for the Norwood procedure, correlated it with survival, and considered its impact on surgical management of hypoplastic left heart syndrome. METHODS: Comprehensive Aristotle score was retrospectively calculated for 39 consecutive Norwood procedures performed from 2001 to 2004. Survival was estimated by the Kaplan-Meier method. RESULTS: The Aristotle scores ranged from 14.5 to 23.5 (mean, 19.12 +/- 2.52; median, 19.5). The score was 20 or greater in 44% (17 of 39) of cases. The most frequent patient-adjusted factors were aortic atresia (n = 16), interrupted aortic arch (n = 9), mechanical ventilation to treat cardiorespiratory failure (n = 19) and shock resolved at time of surgery (n = 13). Hospital mortality was 58.8% (10 of 17) in case of score of 20 or more and 9.1% (2 of 22) for score less than 20 (p = 0.0014). From 2003 on, all patients with a score less than 20 survived. Actuarial estimate of survival at 1 year is 56.2% +/- 7.9% and there have been no late deaths after 1 year. One-year survival is much lower (p = 0.001) for patients with scores of 20 or greater (29.4% +/- 11.05%) compared with those whose scores were less than 20 (77.3% +/- 8.9%). CONCLUSIONS: This study shows significant correlation of comprehensive Aristotle score with hospital mortality and late survival after Norwood palliation. It suggests that operative survival on the order of 90% may be achieved in patients with comprehensive complexity scores of less than 20. Efforts should be devoted to improve survival of high-risk patients (score > or = 20).

Repair of truncus arteriosus and aortic arch interruption: outcome analysis.

BACKGROUND: The excellent results for repair of truncus arteriosus reported in some centers have not applied to patients with associated interrupted aortic arch. This work aims at understanding the discrepancy of results in our own experience. PATIENTS AND METHODS: Ten patients among 83 consecutive children with truncus arteriosus repaired from 1987 to September 2004 who had aortic arch interruption were analyzed, with particular emphasis on clinical presentation and outcome. The comprehensive Aristotle complexity score was calculated for each patient. The Kaplan-Meier method was used to estimate survivals. RESULTS: Preoperative mechanical ventilation was necessary in 5 of the 10 patients; 2 of them were moribund. Associated major lesions were as follows: severe (n = 2) and moderate (n = 4) truncal valve regurgitation, coronary artery anomalies (n = 3) and Di-George's syndrome (n = 4). The comprehensive Aristotle score was at least 20 in 6 patients. There were 5 operative deaths (5 of 10); early mortality was 50% (95% confidence limits: 19% to 81%). These deaths occurred in patients with Aristotle score of 20 or greater (5 of 6 = 83%). All 4 patients who had no moderate or severe truncal valve regurgitation survived the intervention. Survival was a low 37.5% +/- 16.1% from 1 year on compared with a high 95.5% +/- 2.5% for the 73 patients without aortic arch interruption. CONCLUSIONS: This study confirms the predictive value of the Aristotle score, hospital mortality being significantly correlated with the highest Aristotle score (p = 0.024). To improve outcome in these high-risk patients, preoperative management should be optimized, repair should not be delayed, and regurgitant truncal valve should be repaired or replaced.