[The role of staged Fontan operation on early and long-term outcome].

Of 185 patients with single ventricle physiology, 59 patients who underwent Fontan type operations between April 1970 and May 2002 served as subjects. Subjects displayed a median age of 5.2 years and a median body weight of 11.4 kg. In the first 22 years (group 1), 34 patients underwent concomitant right atrium-pulmonary artery (RA-PA) anastomosis, Björk procedure and total cavopulmonary connection (TCPC), while in the last 8 years (group 2), 25 patients underwent staged TCPC, where bidirectional cavopulmonary shunt (BCPS) and obliteration of additional pulmonary blood flow was performed previously. Four cases of early death (group 1:4 patients, group 2:0 patient) and 12 cases of late death (group 1:11 patients, group 2:1 patient) were encountered. Early mortality was 6.8% (group 1:12%, group 2:0%, p = 0.10) and late mortality was 21%. The 5-year survival rate was 85.2 +/- 4.9% (group 1:80.0 +/- 6.8%, group 2:93.8 +/- 6.1%, p = NS), and the 10-year survival rate was 79.6 +/- 6.0%. Staged TCPC, precedent BCPS with obliteration of additional pulmonary blood flow, seems to be beneficial for accurate patient selection for Fontan candidate.

Optimal position of atrial epicardial leads for temporary pacing in infants after cardiac surgery.

BACKGROUND: The atrial epicardial wall of pediatric patients was topographically assessed to identify the optimal position for temporary atrial pacing. METHODS: Unipolar electrodes were fixed at the cephalic wall between the right and left atrial appendages, the interatrial groove, and the right atrial appendage of fifteen pediatric patients who underwent definitive surgical repair. The performance of the three electrodes in terms of pacing patterns and six combinations of bipolar pacing were evaluated in terms of the pacing threshold, P-wave amplitude, slew rate, and lead impedance. RESULTS: Unipolar pacing of the right atrial appendage showed a significantly higher threshold than the other groups. A bipolar configuration of the cephalic atrial wall and interatrial groove had a significantly higher P-wave amplitude than groups without the electrode at the cephalic atrial wall, and a significantly higher slew rate than a unipolar configuration of the atrial appendage. CONCLUSIONS: Bipolar pacing with the negative electrode at the cephalic atrial wall and the indifferent electrode at the interatrial groove is the most efficient method for pediatric patients.

Left atrial appendage insertion for right ventricular outflow tract reconstruction.

BACKGROUND: The left atrial appendage (LAA) may serve as an alternative to the pulmonary arterial wall for right ventricular outflow tract (RVOT) reconstruction without an extracardiac conduit. METHODS: Five consecutive patients with pulmonary atresia or severe stenosis underwent corrective (n = 4) or palliative (n = 1) RVOT reconstruction using an LAA insertion. Surgery was performed to treat tetralogy of Fallot, double-outlet right ventricle, or transposition of the great arteries. By inserting the LAA into the obstructed portion, the width of the posterior wall of the RVOT was 20 mm or more. The anterior half of the RVOT was then augmented with pericardial patch. RESULTS: There were no early or late postoperative deaths, and no major complications (arrhythmias, thrombo-embolic episodes, infective endocarditis, need for reoperation). The postrepair systolic right ventricular-to-systemic arterial pressure ratio was 0.61 +/- 0.26. Color Doppler flow mapping revealed that the reconstructed RVOT was nonobstructive and had nonturbulent flow. No thrombus or pseudoneointimal formation was observed in the RVOT. CONCLUSIONS: LAA insertion in the RVOT is an effective alternative to, or adjunct of, direct anastomosis. It offers several advantages, including fewer early and midterm complications and avoiding the use of an extracardiac conduit.

[Effect of Down's syndrome on perioperative and long-term prognosis after ventricular septal defect repair].

In this study, we investigated perioperative and long-term prognosis and the risk of major complications after repair of ventricular septal defect in 48 patients with Down's syndrome who underwent ventricular septal defect repair between May 1980 to August 1999 were compared with those in 48 patients with normal chromosomes matched for age and time period. Pp/Ps were significantly lower after the operation in both groups; however perioperative and postoperative Pp/Ps of Down's syndrome group were significantly higher than that those of control group. The duration of intubation was significantly longer in the Down's syndrome group and the case-control study revealed that the risk of long intubation (> or = 7 days) was significantly higher in the Down's syndrome group, but the incidence of PH crisis did not differ between the 2 groups. The main reasons of prolonged intubation period were respiratory complications such as pneumonia or atelectasis. In Down's syndrome group, a 5 months old boy died of heart failure on the 5th postoperative day. All other patients were survived through a mean follow-up period of 122.4 months (the follow-up rate was 95.8%). In conclusion, the perioperative and long-term prognosis after ventricular septal defect repair in patients with Down's syndrome were similar to those in patients with normal chromosome.

Placement of interatrial patch suture lines in atrioventricular canal defect repair.

BACKGROUND: The placement of the suture line for interatrial patches in complete and incomplete atrioventricular canal defect repairs varies from surgeon to surgeon despite established anatomic knowledge of the atrioventricular conduction system. This study describes our technique for it and reviews early and long-term outcomes. METHODS: Between 1980 and 1999, 64 infants and children underwent repair of either complete (n=39) or incomplete (n=25) atrioventricular canal defects. Thirty-four of the children (53.1%) had Down's syndrome. The suture line for the interatrial patch originated on either the artificial or native ventricular septal crest and continued leftward above the annulus of the left inferior leaflet of the atrioventricular valve at the posteroinferior corner. All stitches were placed in a horizontal mattress or U-shaped fashion. RESULTS: The operative survival rate was 94% (4 early deaths) and the overall survival rate was 85% (6 late deaths). Atrioventricular heart blocks occurred in none of the patients. Although left-sided atrioventricular function significantly improved with repair, two patients (3.1%) required reoperation for valve replacement because of residual or recurrent insufficiency. CONCLUSIONS: This suture technique for interatrial patches is straightforward and results in a low incidence of heart block and a low re-operation rate for left atrioventricular valve insufficiency.

Omental flap for mediastinitis after median sternotomy in asplenia syndrome and gut malrotation.

We describe a 12-year-old patient with asplenia syndrome and gut malrotation who, after an interim step before a modified Fontan operation, developed life-threatening mediastinitis. A flap of the omentum arising from the transverse colon, longitudinally located in the left of the abdomen, was created and transferred to the mediastinum after a division of the arterial arcade at its most caudal extent. Her postoperative course was uneventful, and 12 months later, the modified Fontan operation was successfully completed. Although visceral heterotaxy results in an omental deformation, it does not preclude the use of an omental flap.

Factors influencing arterial oxygenation early after bidirectional cavopulmonary shunt without additional sources of pulmonary blood flow.

OBJECTIVES: Although the arterial oxygen saturation after bidirectional cavopulmonary shunting should theoretically be homogeneous if additional pulmonary flow is obliterated, the arterial oxygen saturation has been found to vary in clinical practice. Knowledge of the preoperative and operative determinants of arterial oxygen saturation early after bidirectional cavopulmonary shunting may lead to a better understanding of this unique physiology. METHODS: Thirty-five patients who underwent bidirectional cavopulmonary shunting with obliteration of additional pulmonary flow were included in this study. The arterial oxygen saturation was determined at the 5 time points over a 48-hour period. Multivariable regression analysis was used to identify the independent predictors of the arterial oxygen saturation. RESULTS: No significant interval changes occurred in the arterial oxygen saturation during the 48 hours after bidirectional cavopulmonary shunting, which ranged from 61.6% to 95.6%. There was a significant inverse correlation between the postoperative superior vena cava pressure and the arterial oxygen saturation (P =.003). A low arterial oxygen saturation early after bidirectional cavopulmonary shunting was a predictor of mortality or exclusion from univentricular repair within 24 months (P =.012, odds ratio = 1.14). Of 11 factors identified by univariable analysis, multiple regression analysis indicated that age less than 8 months at the time of shunting (P <.0001) and ventricular volume overload (P =. 002) predicted a lower arterial oxygen saturation after bidirectional cavopulmonary shunting. CONCLUSIONS: Even without additional sources of pulmonary blood flow, several preoperative factors, including younger age and severe ventricular volume overload, predicted a decrease in the arterial oxygen saturation early after bidirectional cavopulmonary shunting. This, in turn, predicted poor outcome during 2 years of follow-up.

Primary repair of complete transposition of the great arteries with complete atrioventricular septal defect.

We successfully corrected complete transposition of the great arteries associated with complete atrioventricular septal defect in a 50-day-old infant in concomitant arterial switch operation and two-patch repair. The combination of these 2 complex anomalies is very rare, and primary anatomical repair is feasible in such patients.

Aortoventriculoplasty in patients with aortic malposition.

Aortoventriculoplasty was applied successfully for recurrent combined subvalvular and valvular aortic obstruction that developed after intraventricular baffle repair of a cardiac anomaly in 2 patients with associated anterior malposition of the aorta. A single baffle for the left ventricular tunnel was also used for aortic annulus augmentation.

Hemashield implantation in young patients with congenital cardiovascular lesions.

BACKGROUND: There is substantial controversy regarding the use of Hemashield in young patients. METHODS: Twenty-one consecutive patients younger than 20 years of age with a variety of congenital cardiovascular lesions underwent surgical procedures using a Hemashield woven graft. Hemashield was used for reconstruction of the aortic wall (n = 16), ventricular septum (n = 10), and right ventricular free wall or pulmonary artery (n = 6). RESULTS: A sterile inflammatory reaction was observed including high fever, increased white cell count, and elevated plasma C-reactive protein concentration for up to 4 weeks after implantation. Multivariable analysis identified the use of Hemashield in the right ventricular free wall or pulmonary artery as an incremental risk factor for elevation of plasma C-reactive protein concentration during the first 3 weeks after implantation (p = 0.002). There were no midterm complications including restenosis of the grafts in the right ventricular outflow tract. CONCLUSIONS: Hemashield can be used in a variety of situations for reconstruction of congenital cardiovascular lesions in young patients. Impregnated collagen can cause a significant systemic inflammatory reaction for several weeks after implantation, especially when used in the low-pressure right heart.

Outcome of patients with cyanotic congenital heart disease undergoing a second systemic-to-pulmonary artery shunt.

BACKGROUND: Multiple systemic-to-pulmonary artery shunts often represent a deviation from the initial management strategy for cyanotic congenital heart disease. This study analysed the outcome in patients undergoing a second shunt. METHODS: Between 1965 and 1998, 80 patients required a second shunt. Patient age ranged from 11 days to 11.2 years at the initial shunt, and 4 months to 25.6 years at the second shunt. The interval between shunts ranged from 11 days to 19.6 years. RESULTS: The patient survival rates at 1, 6, 12, 60 and 120 months following the second shunt were 95.0 +/- 2.4%, 92.5+/-3.0%, 87.4+/-3.7%. 82.4+/-4.5% and 74.8+/-5.8%, respectively. Although excess pulmonary flow was not encountered after the second shunt, mode and incidence of morbidity were otherwise similar to the first one. Between 9 months and 7.5 years after the second shunt, 24 patients underwent successful definitive repair. Multivariable analysis identified pulmonary atresia (p=0.027) and a short (<1 year) interval between the two shunts (p=0.034) as the independent risk factors for long-term shunt failure. Single ventricle physiology (p=0.002) and a central approach for the second shunt (p=0.016) were independent risk factors for lack of application, or failure of intracardiac definitive repair. CONCLUSIONS: A significant limitation in longevity and quality of life is common in patients requiring a second shunt, especially those associated with pulmonary atresia, the single ventricle physiology heart, or ungraftably hypoplastic contralateral branch pulmonary artery to the first shunt. Since excess pulmonary blood flow leading to congenital heart failure and/or ventricular diastolic dysfunction is unlikely, all patients who preclude definitive repair due to decreased pulmonary blood flow even after the first shunt should be shunted again.

Modified ultrafiltration improves carbon dioxide removal after cardiopulmonary bypass in infants.

Little is known about the role of modified ultrafiltration in ameliorating the adverse effects of the cardiopulmonary bypass on pulmonary function in infants. Twenty-nine nonrandomized consecutive infants (<12 months of age) who underwent unrestrictive ventricular septal defect closure between 1995 and 1998 were included in this study. Down's syndrome was associated in 9 patients. The actual ventilator settings were highly homogeneous among all patients and each time point in the study. Fourteen infants received modified ultrafiltration after the discontinuation of cardiopulmonary bypass. Fifteen untreated patients served as the control group. Correlates of cardiac and pulmonary functions for both groups were compared. The arterial carbon dioxide tension in the experimental group was significantly lower than in the control group from 20 to 240 min after bypass. Arterial oxygenation and pulmonary arterial pressure were similar in the 2 groups. Modified ultrafiltration improves carbon dioxide removal after cardiopulmonary bypass in infants. This may potentially convey a beneficial impact on hemodynamics.

Surgical management of the straddling mitral valve in the biventricular heart.

BACKGROUND: The straddling mitral valve in the biventricular heart is a rare condition that may complicate biventricular repair. METHODS: Treatment and outcomes in 5 consecutive patients who underwent primary repair between 1992 and 1997 were reviewed. Their ages at repair ranged from 2 months to 8 years. Three patients had a double-outlet right ventricle with a subaortic (n = 2) or subpulmonary (n = 1) ventricular septal defect. Two patients had transposition of the great arteries (S,D,D), a ventricular septal defect, and left ventricular outflow tract obstruction. The attachments of the papillary muscles of the straddling mitral valves were located on the right ventricular aspect of the ventricular septum. Four patients underwent baffle partitioning of the ventricular cavity. The baffle suture line was used to secure the chordae tendineae crossing the ventricular septal defect, or was intentionally omitted at the papillary muscle. The right ventricular outflow tract was reconstructed with patch augmentation, an extracardiac conduit, or an arterial switch operation. One patient with transposition who had a giant papillary muscle to the straddling mitral valve associated with abnormal insertion of the tricuspid valve on the conal septum underwent univentricular repair. RESULTS: There were no early or late postoperative deaths. There was no mitral valve dysfunction, left ventricular outflow tract obstruction, or heart block in the 4 patients who underwent biventricular repair. CONCLUSIONS: Although there are several exceptional situations in which ventricular partitioning may result in early and late complications, a straddling mitral valve does not preclude biventricular repair.

Effects of arteriovenous shunt on ventricular function in dog.

BACKGROUND: The bidirectional cavopulmonary shunt has been increasingly accepted as an interim step to the Fontan operation. However, the effect(s) of chronic volume overload on ventricular function are not yet well understood. METHODS: Twelve mongrel dogs, with (chronic volume overload group), or without (control group) a femoral arteriovenous shunt created 8 weeks before the assessment, were subjected to a right heart bypass from the right atrium to the proximal pulmonary trunk. Nonpulsatile perfusion via the bypass was achieved using a centrifugal pump and cross-clamping of the pulmonary trunk. Left ventricular function was evaluated using the end-systolic elastance and the Doppler flow pattern on echocardiograms (epicardiac and transesophageal, simultaneously) during acute volume loading. RESULTS: The left ventricular weight and the left ventricular weight/end-diastolic volume ratio showed no change from control values. The sum of the isovolumetric contraction time and the isovolumetric relaxation time divided by the ejection time remained constant during acute volume loading in the chronic volume overload group, while an increase was demonstrated in the control group. The chronic volume overload group showed a lower Ees (30.8 +/- 16.4 mmHg/cm2 vs. 107.6 +/- 70.3 mmHg/cm2, p = 0.03) than the control group. CONCLUSIONS: The global ventricular performance changed with chronic adaptation to the arteriovenous shunt, and became resistant to acute volume loading. Left ventricular contractility under nonpulsatile pulmonary perfusion was impaired by chronic volume overload, which is deleterious to the Fontan operation.

The surgical treatment of fixed subaortic stenosis: a clinical experience in Japan.

We report herein the results of a retrospective study conducted on ten consecutive Japanese patients who underwent successful surgical relief of fixed subaortic stenosis between 1972 and 1994 at ages ranging from 8 months to 21 years, and followed for 3.6 years and 26 years. Associated cardiovascular defects were present in six patients, two had a history of infective endocarditis, a discrete fibrous ring was found in nine patients, and a redundant abnormal sheet was found in one. A stenotic structure was removed in nine patients and incised in one, while myotomy was additionally performed in one. There were no early complications or deaths. Cardiac catheterization revealed a significant decrease in the peak systolic pressure gradient from 84+/-22 mm Hg preoperatively to 32+/-22 mm Hg postoperatively (P = 0.0017). Reoperation of an aortic valve replacement with or without valvular annulus enlargement was required in four patients because of a small annulus with aortic insufficiency or infective endocarditis. Infective endocarditis was a major cause of late mortality (n = 1) and morbidity (n = 1), but the remaining eight patients have been asymptomatic. Thus, although this lesion is relatively rare in Japan, the typical discrete type may be more common than previously believed. While a relief operation is associated with low early mortality, the palliative aspect regarding pathology of the aortic valve should not be underestimated, including poor growth of the valve annulus, deterioration of aortic insufficiency, and infective endocarditis. The most appropriate operative procedure for reoperation remains to be evolved.

Mitral valve replacement in patients younger than 6 years of age.

UNLABELLED: We present our experience in mitral valve replacement (including left-sided tricuspid valve in corrected transposition) in patients younger than 6 years of age. The long term results were examined with special focus on re-replacement of the valve. Between 1974 and 1995, we performed mitral valve replacement in 14 patients younger than 6 years of age, with no operative mortality. There were 3 late deaths, caused by endocarditis, valve thrombosis, and congestive heart failure, respectively. The five-year-survival rate after primary replacement was 85%, and the ten-year-survival rate was 75%, using Kaplan-Meier analysis. Ten patients (11 occasions) required repeated mitral valve replacements at 2 months to 17 years after the original replacement. The indication for the second or third mitral valve replacement was paravalvular leakage (2 patients), valve thrombosis (1 patient), degeneration in the porcine prosthesis (3 patients), and patient outgrowth of the original small prosthesis (5 patients). Again there was no operative mortality. One patient who suffered from multiple occasions of valve thrombosis died at two years after the second replacement. All patients who had outgrown the prosthetic valve received larger prosthesis at the second replacement than at the primary replacement. The actuarial percentage of freedom from valve-related events at 3 years, 5 years, and at 10 years, was 50%, 37%, and 8%, respectively. CONCLUSIONS: Mitral valve replacement in patients younger than 6 years of age can be performed relatively safely, but meticulous follow-up and appropriate decision making for re-replacement is mandatory for the long-term survival of these patients.

Prognosis of Marfan and non-Marfan patients with cystic medial necrosis of the aorta.

The characteristics and prognosis of patients with cystic medial necrosis of the aorta were reviewed. Subjects were 46 patients who underwent aortic and/or aortic valve surgery between August 1965 and October 1994. All had histologically documented cystic medial necrosis including 22 Marfan patients. The patients with Marfan syndrome were substantially younger (median age, 32 vs 50 years; p < 0.05), and experienced annulo-aortic ectasia more frequently {81% (17/22) vs 46% (11/24); p < 0.05} than those without the syndrome. Sixty-eight percent (15/22) of the Marfan patients and 63% (15/24) of the non-Marfan patients experienced complications with aortic dissection, although not to a significant degree. The hospital mortality rate was 14% (3/22) in the Marfan group and 21% (5/24) in the non-Marfan group, which was also not significant. Of the 38 survivors, developments in the health of 37 were completely followed-up until October 1997. The cardiovascular event-free rate for Marfan patients at 10 years (28%) was lower than that for non-Marfan patients (68%, p = 0.057), whereas the actuarial survival rates at 10 years were nearly equal (72% for the Marfan patients and 74% for the non-Marfan patients). Reoperation was the first cardiovascular event in 77% (10/13) of the Marfan patients and in 14% (1/7) of the non-Marfan patients (p < 0.05). Cardiovascular event was the main cause of late death both for Marfan patients (80%; 4/5) and for non-Marfan patients (86%; 6/7). In conclusion, independent of the presence of Marfan syndrome, careful follow-up is necessary for patients with cystic medial necrosis of the aorta to eliminate serious late complications.

Complications following reparative surgery for aortic coarctation or interrupted aortic arch.

Repair of aortic coarctation or interrupted aortic arch continues to be associated with major long-term morbidity. Thus, we conducted a review of 87 consecutive patients who underwent aortic arch repairs, focusing particular attention on the complications that developed. A two-stage strategy was employed if cardiac lesions were associated. The median age at surgery was 1.5 months with a range of 12 h to 56 years. The aortic arch was repaired using end-to-end anastomosis, subclavian flap aortoplasty, subclavian arterial turning-down aortoplasty, patch aortoplasty, tube graft interposition, or other methods. There were 10 patients who died soon after repair, and all of whom had complex cardiac anomalies. Of the remaining 77 patients, 8 developed recurrent stenosis. These 8 patients were all similar in age, being under 3 months old, and weighing 4 kg or less. A multivariable analysis of the infants identified interrupted aortic arch as an independent risk factor for the development of this complication with an odds ratio of 6.45. Complications following prosthesis-free techniques were similar in prevalence and timing. All reinterventions were mortality-free, but catheter dilation and patch aortoplasty were not always successful. Three extraanatomic bypasses were successfully performed, and one adult who had undergone a previous graft and pseudoaneurysm operation was successfully treated with an extraanatomic bypass. These findings led us to conclude that the initial repair should be performed without a prosthesis, and that reintervention for stenosis should combine catheter dilation and extraanatomic bypass.