Onset of pulmonary stenosis after arterial switch operation for transposition of great arteries with intact ventricular septum.

INTRODUCTION: Pulmonary stenosis remains the most frequent complication and cause of reintervention after the arterial switch operation for transposition of the great arteries We investigated the onset, incidence, and outcome of pulmonary stenosis after arterial switch operation in neonates with transposition of the great arteries and intact ventricular septum. METHODS: Arterial switch operation using Lecompte maneuver was performed in 222 neonates with transposition of great arteries and intact ventricular septum. Complete medical records with serial echocardiograms were available for 174 (73%) patients and were reviewed for incidence of postoperative pulmonary stenosis defined as a thickened and doming pulmonary valve and/or a pressure gradient of >25 mmHg. RESULTS: During a mean follow-up of 14.4 ± 0.54 years, 31 children developed pulmonary stenosis. Onset of significant stenosis occurred as early as 30 days and as late as 10 years after arterial switch operation. Uncomplicated interventional balloon/stent angioplasty was performed in 11 patients with supravalvular stenosis (mean pressure gradients of 65 mmHg). Severe restenosis occurred in these patients post-angioplasty (range 2-7 years). In other 10 patientseither patch enlargement of the area involved or angioplasty were performed. Freedom from intervention was 68.6±8.7% at 1 year and 42.8.1±9.5% at 15 years and onwards. CONCLUSION: Over time, pulmonary stenosis developed after arterial switch operation. Balloon angioplasty for supravalvular pulmonary stenosis could be the initial treatment of choice owing to the high success rate. Surgical intervention is offered to those with pulmonary valve stenosis having pressure gradients of >50 mmHg, and for re-stenosis after intervention/stent implantation.

Pulmonary and caval blood flow patterns in patients with intracardiac and extracardiac Fontan: a magnetic resonance study.

AIMS: We compared in vivo blood flow and pulsatility after different types of Fontan operation using magnetic resonance imaging. MATERIAL AND METHODS: A total of 37 consecutive patients (mean age 19+/-7.9 years, 7.3+/-3.2 years after Fontan operation), 7 with atriopulmonary anastomosis (APC), 18 with intra-atrial lateral tunnel (LTFO) and 12 with extracardiac Fontan (ECFO) were studied using magnetic resonance phase-contrast velocity mapping. Blood flow (volume flow) in the superior vena cava (SVC), inferior vena cava (IVC) and both pulmonary arteries were measured and a pulsatility index was calculated for each vessel. RESULTS: For all modifications, the blood flow distribution between the SVC and IVC was normal (1:2). Patients with APC had a normal pulsatility, a dilated right atrium, partial backward flow in the IVC and physiological blood flow distribution between the pulmonary arteries. LTFO and ECFO patients had no retrograde flow in the IVC, equal blood flow distribution between the pulmonary arteries and very low or absent pulsatility. CONCLUSIONS: MRI allows hemodynamic quantification and characterization of various types of Fontan modifications and may be a valuable tool to predict Fontan failure. Despite showing normal pulsatility, patients with APC have right atrial dilatation and partial backward flow in the IVC, demonstrating suboptimal Fontan circulation. LTFO and ECFO both produce unidirectional antegrade flow in the IVC but pulsatility is very low or absent, which may promote poor pulmonary artery growth and increase of pulmonary vascular resistance contributing to late Fontan failure.

Pulmonary regurgitation is a powerful factor influencing QRS duration in patients after surgical repair of tetralogy of Fallot. A magnetic resonance imaging (MRI) study.

AIMS: QRS prolongation is a negative prognostic factor for the development of ventricular arrhythmia after repair of tetralogy of Fallot (TOF). In this MRI study, we performed a multivariate analysis to determine the influence of volumetric and functional parameters as well as time factors on QRS duration. METHODS AND RESULTS: Sixty-seven patients after surgical repair of TOF were studied using a 1.5T MRI. Measurement of the ventricles was performed with a multislice-multiphase sequence. Left and right ventricular volumes, ejection fractions (EF) and myocardial masses were determined. Pulmonary regurgitant fraction (PRF) was quantified by velocity encoded flow measurement in the main pulmonary artery. Maximum QRS duration was taken from a 12-channel ECG. Mean maximum QRS duration was 132 ms (+/- 29 ms). Mean PRF was 29.2% (+/- 13.4%). QRS duration correlated significantly with PRF (r = 0.49; p < 0.01; n = 54) and with right ventricular enddiastolic volume index (RVEDVI) (r = 0.29; p < 0.05; n = 67). Multivariate analysis revealed that the combination of PRF, postoperative period, age at surgical repair, and left ventricular (LV) enddiastolic volume are correlated with QRS prolongation. CONCLUSION: In patients after repair of TOF, pulmonary regurgitation is related to QRS prolongation. Furthermore, even LV size plays a role in the enlargement of the QRS complex.

Comparison of modified short axis view and apical four chamber view in evaluating right ventricular function after repair of tetralogy of Fallot.

BACKGROUND: In clinical settings an easy and reliable method for following up right ventricular (RV) function in patients after repair of tetralogy of Fallot (TOF) is needed. It is, however, unclear whether the novel modified short axis view from echocardiography is superior to the apical four chamber view in this aspect. MATERIALS AND METHODS: Thirty postoperative TOF patients with median age 17 years (range 6-45 years) and follow up period of 10 years (range 0.5-40 years) were examined echocardiographically using the apical four chamber view and the novel modified short axis view. RV areas in end-systole (Amin) and end-diastole (Amax) were measured and an area fraction [(Amax - Amin)/Amax * 100%] was calculated from the respective view. RV ejection fraction was assessed through magnetic resonance imaging (MRI). The RV area fractions from echocardiography were compared to the RV ejection fraction. RESULTS: The right ventricular area fraction derived from the modified short axis view was significantly lower than that from the apical four chamber view (34.3+/-9.1% vs. 42.5+/-10.2%, p=0.007). Both the RV area fractions obtained from the modified short axis view (r=0.674, p<0.001) and from the apical four chamber view (r=0.512, p=0.025) correlated significantly with the MRI derived RV ejection fraction. CONCLUSION: The novel modified short axis view from echocardiography may be superior to the apical four chamber view for routine follow up of patients after TOF repair, in whom the right ventricular outflow tract plays an important role in the right ventricular systolic function.

Correction of congenital heart defects in Jehovah's Witness children.

UNLABELLED: Between August 1989 and July 2003 14 Jehovah's Witness children with congenital heart defects (CHD) aged under 14 years (median 2.9 years) and with a median weight of 14 kg underwent 16 operations with cardiopulmonary bypass (CPB). Five children had been operated on previously between one to three times. Preoperatively, 7 children were prepared with oral iron supplementation and 10 received erythropoietin. Mean hemoglobin (Hb) at admission was 14.4 g/dl (range 10.9 - 19.2). The cardiopulmonary bypass (CPB) circuit was modified to reduce total priming volume. High doses of aprotinin were administered. The modified ultrafiltration (MUF) circuit, used in 7 patients, was parallel to the ECC circuit with continuous circulation of the blood through a small shunt between the arterial and venous lines. Operations performed consisted of VSD closure (3 pts.), ASD closure (3 pts.), Fontan operation (2 pts.), and complete AV canal correction, aortic commissurotomy, Ross operation, Glenn shunt, cor triatriatum correction, MV reconstruction combined with left outflow tract stenosis resection, correction of absent pulmonary valve syndrome, and correction of tetralogy of Fallot in one patient each. There were no deaths. Mean duration of CPB was 192 min and mean aortic cross-clamp time 40 min. The Hb value at the end of the operation was 4.9 - 14.5 g/dl (mean 9.6) and at discharge it was 7.1 - 14.5 g/dl (mean 15.5). No blood or blood products were used in any patient. CONCLUSION: Bloodless cardiac surgery with and without CPB can be safely performed in Jehovah's Witness infants and children.

[Influence of myocardial mass of the univentricular heart on exercise capacity in patients with functional single ventricle and Fontan surgery]. / Einfluss der myokardialen Muskelmasse des univentrikulären Herzens auf die Belastbarkeit bei Patienten mit funktionell univentrikulärem Herz und Fontan-Operation.

BACKGROUND: The Fontan operation causes an acute decrease of volume overload of the univentricular heart followed by changes in ventricular geometry. The postoperative increase of myocardial mass-volume-index (MVI) may alter ventricular diastolic function. In this study, we analysed whether the increase in MVI and changes of the ventricular geometry have an effect on the decrease of the exercise capacity in patients with Fontan surgery. METHODS: We examined the cardiopulmonary function of 24 patients with functional single ventricle and Fontan operation 3.63 +/- 1.97 years after surgery (m = 14, w = 10, age: 14.57 +/- 9.74 years) using a bicycle cardiopulmonary exercise testing. The parameters of exercise capacity and cardiopulmonary function were correlated with Magnetic Resonance Imaging (MRI) parameters such as the MVI, enddiastolic ventricular muscle mass (EDMM) und endsystolic volume (ESV). RESULTS: The exercise capacity was 2.06 +/- 0.54 W/kg (60.63 +/- 15.75% of the norm) and VO(2)max was 27.41 +/- 8.87 ml/min/kg (60.91 +/- 19.7% of the norm). There was a positive correlation of exercise capacity and VO(2)max with ESV (r(2) = 0.2572, p = 0.033) and EDMM (r(2) = 0.2544, p = 0.024), but none with the MVI. CONCLUSION: Myocardial hypertrophy may influence the myocardial performance of the univentricular heart and thereby the physical performance in children and adults with Fontan circulation.

Early and medium-term results after modified Fontan operation in adults.

OBJECTIVE: Single ventricle palliation is rarely performed in adults and the results are less optimal than in children. In this article we analyze our experience with the modified Fontan operation in this age group. METHODS: Data of 15 consecutive patients with single ventricle with a mean age of 26 (range 16-38) years, who underwent Fontan operation between 3/92 and 1/2000 were retrospectively analyzed. Five patients had previously had an aortopulmonary shunt in childhood and two patients had previously received a bi-directional cavopulmonary shunt as adults. Eleven patients were preoperatively in NYHA class III and four in class II. The main factors for the selection of the patients before surgery were well-developed pulmonary arteries with lower lobe index 120+30 mm/m(2), pulmonary artery pressure <18 mmHg, good cardiac function and enddiastolic systemic ventricular pressure <12 mmHg. The lateral tunnel Fontan operation (LTFO) was performed in ten patients and extracardiac Fontan operation (ECFO) in five. A fenestration 4-5 mm in size was constructed in all patients with LTFO and in three of five patients with ECFO. RESULTS: There was one intraoperative and one late death (total mortality 13%). The mean extubation time and hospital stay were 24 h and 21 days, respectively. Severe postoperative complications were observed in three patients (20%). Two LTFO patients out of a total of eight patients (53%) with perioperative arrhythmias received a permanent pacemaker due to bradyarrhythmia. During the median follow-up of 5.0 (range 2.3-10.1) years, four patients developed arrhythmias; one of them had new onset bradyarrhythmia after LTFO and required permanent pacemaker implantation. The median postoperative oxygen saturation was 93% (range 90-98%). NYHA class improved significantly in 12 survivors. Cardiac catheterization (0.5-4 years postoperatively, n=12) showed excellent Fontan hemodynamics in all patients. CONCLUSIONS: The modified Fontan operation can be performed in adults with acceptable early and midterm mortality and morbidity and leads to either complete or marked relief of cyanosis and enhanced exercise tolerance in all survivors. Postoperative arrhythmias are one of the main drawbacks but the incidence of arrhythmias after ECFO seems to be lower. The long-term follow-up has yet to be established.

Circulatory arrest and renal function in open-heart surgery on infants.

This study was designed to evaluate the impact of circulatory arrest on renal function in open-heart surgery on infants. Renal function was described by diuresis, urine/plasma creatinine ratio, creatinine clearance, urinary albumin, and N-acetyl-beta-D-glucosaminidase measurements. Seven patients who underwent circulatory arrest (group 1) were compared with 37 patients operated on with cardiopulmonary bypass without circulatory arrest (group 2). In group 1, bypass time was 164 minutes and the lowest body temperature was 25.6 degrees C (median), compared with 106 minutes and 31.3 degrees C in group 2 (p < 0.05). Although diuresis and creatinine clearance revealed no differences between the groups, urine measurements, which had normal values before cardiopulmonary bypass, increased during reperfusion to 58.6 (range 16.2-75.5) mg gCrea(-1) albumin and to 14.8 (range 1.6-21.8) U gCrea(-1) N-acetyl-beta-D-glucosaminidase in group 1, compared with 8.1 (range 0-127.7) mg gCrea(-1) and 1.9 (range 0-47.8) U gCrea(-1) in group 2 (p < 0.05). Thus, deep hypothermic circulatory arrest (DHCA) subjected the kidney to ischemia reperfusion injury. Although the findings are mild and do not indicate severe ischemic renal damage, potential renal damage by DHCA should be taken into account when planning surgical procedures for congenital heart disease patients with additional risks of acute renal failure.

Hemorheology and renal function during cardiopulmonary bypass in infants.

BACKGROUND: Acute renal failure is an occasional complication after cardiopulmonary bypass in infants. Whereas it is well known that postoperative hemodynamics inflict acute renal failure, the influence of extracorporeal circulation on the kidney is less clear. Moreover, changes in blood viscosity occur during and after surgery, which may influence renal dysfunction. For this reason, we investigated the impact of blood viscosity on renal function during cardiopulmonary bypass. METHODS: In 34 patients weighting less than 10 kg, we performed repeated analysis of urine, blood, and plasma viscosity. RESULTS: Polyuria and proteinuria that appeared during cardiopulmonary bypass indicated an elevated transglomerular filtration gradient, which recovered within 24 hours. The appearance of N-acetyl-beta-D-glucosaminidase in the urine, and elevated excretion of sodium, were additionally indicative of mild tubular damage. Elevation of blood viscosity during hypothermic perfusion showed a statistical correlation with proteinuria and N-acetyl-beta-D-glucosaminidaseuria. With hypothermia, the relation of blood viscosity to plasma viscosity became stronger, while the relation to the hematocrit decreased compared to normothermia. CONCLUSIONS: During cardiopulmonary bypass perfusion, the kidney can be stressed by proteinuria and mild tubular damage. Our data provide evidence that the kidneys can be protected by improved blood viscosity during cardioplegia, but this needs confirmation in a prospective interventional study.

Preliminary analysis of arrhythmias after the Fontan operation with extracardiac conduit compared with intra-atrial lateral tunnel.

BACKGROUND: It is to be expected that avoidance of the atrial suture line during extracardiac Fontan operation (ECFO) decreases the risk of postoperative arrhythmias. METHODS: Two groups of consecutive patients (23 with lateral tunnel (LTFO) and 24 with extracardiac conduit) who underwent successful Fontan operations between 5/93 and 10/98 were comparatively analyzed. All patients had postoperatively standard ECG and 24-hour monitoring. During follow-up, all patients had 2 - 8 (mean 3) standard ECG recordings per year and 76 % of the patients a 24-hour Holter ECG once a year. RESULTS: Median follow-up after ECFO and LTFO was 2.4 years and 4.5 years, respectively. The incidence of supraventricular tachyarrhythmias and bradyarrhythmias after ECFO versus LTFO was lower early after operation and during follow-up (p < 0.05). In follow-up, 20 ECFO patients (91 %) versus 11 patients after LTFO (52 %) remained in sinus rhythm (p < 0.01). Pacemaker insertion was required in 7 (33 %) LTFO patients but none of the ECFO patients (p < 0.01). CONCLUSIONS: The extracardiac Fontan operation decreases the incidence of early and medium-term postoperative arrhythmias. Comparative long-term results are not yet available.

Thrombosis of intracardiac or extracardiac conduits after modified Fontan operation in patients with azygous continuation of the inferior vena cava.

BACKGROUND: The Fontan procedure in patients with azygous continuation of the inferior vena cava, requires a cavo-pulmonary anastomosis, and deviation of the hepatic venous drainage to the pulmonary arteries using an intra- or extracardiac conduit. METHODS: We report thrombosis of two pericardial conduits and one Gore-Tex (W. L. Gore & Assoc, Flagstaff, AZ) graft used for deviation of hepatic venous blood to the pulmonary arterial tree in 3 patients aged 11, 24, and 28 years. Two of the conduits (pericardial) were intraatrial. The Gore-Tex graft was placed in an extracardiac position. The two pericardial conduits obstructed completely. RESULTS: One patient died at reoperation. In the 2nd patient, the conduit was excised and the hepatic veins were allowed to drain into the atrium. In the 3rd patient, partial thrombosis of the Gore-Tex conduit was noted 30 months after operation. The thrombus resolved with oral anticoagulation. CONCLUSIONS: Conduits carrying only hepatic venous blood flow may have a higher risk of thrombosis. Anticoagulation or alternative methods of directing hepatic blood flow to the pulmonary circulation must be considered in these patients.

Primary cardiac tumours: when is surgery necessary?

OBJECTIVE: Primary cardiac tumours are rare. The literature predominantly contains series on myxomas in adults and only a few long-term series that involve the very different primary cardiac tumours in early childhood. As foetal ultrasonography has continued to improve, cardiac tumours are increasingly detected early before significant symptoms develop. It is a challenge for paediatric cardiologists and surgeons to ascertain which patients need surgery and which will benefit from conservative follow-up. METHODS: A retrospective review of a 10-year period revealed 51 tumours in 26 children (median age: 1 month). Analysis was by presentation, location, associated findings, interventions, histological findings, and clinical course. RESULTS: The most common tumours were rhabdomyomas (29), fibromas (nine), teratomas (two), and haemangiomas (two). The tumour location was the right ventricle in 24 and the left ventricle in 22 patients. The symptoms varied between abnormal heart murmur (20), arrhythmia and conduction abnormalities (ten), obstruction of the outflow tract >30 mmHg (nine), severe cyanosis (three) and congestive heart failure (two). Fourteen children with haemodynamic compromises underwent surgery. There was one post-operative death and one heart transplantation after bridging with an assist device. There was no tumour recurrence even when resection was incomplete. Nine of 13 children with rhabdomyomas had spontaneous tumour regression without intervention. CONCLUSIONS: Most of the cardiac tumours in children are benign. Spontaneous regression is possible not only in rhabdomyoma. Surgical intervention is only required for children who develop relevant clinical symptoms. Total resection of the tumour is not the only therapeutic aim; more important is the restoration of the best possible heart function.

[Congenital coronary fistulas: the most frequent congenital coronary anomaly]. / Angeborene Koronarfisteln--die häufigste angeborene Koronaranomalie.

Congenital arteriovenous coronary fistulae are a rare condition of a direct communication between a coronary artery and one of the cardiac chambers, the coronary sinus, the superior vena cava or the pulmonary artery. In most instances the diagnosis is made during heart catheterization for coronary or congenital heart disease. Whether congenital coronary artery fistulae should be treated by transcatheter intervention or surgery and in which patients fistula closure should be performed is controversial. This report summarizes our experience of the surgical treatment of congenital arteriovenous coronary fistulae in 14 patients at the Deutsches Herzzentrum Berlin between March 1988 and April 1997. There were seven females and seven males aged from 3 to 67 years (mean 47 years). We analyzed the symptomatic status (NYHA class) preoperatively and in the late outcome, the preoperative angiographic data and the surgical techniques. The right coronary artery was affected in six, the left in six, and both arteries in two cases. The fistulae drained into the pulmonary artery in eight cases, into the superior vena cava and into the right atrium in two cases, and into the right ventricle and into the coronary sinus once. Fistula closure was unsuccessfully attempted interventionally in two patients and surgically in one patient in another institution. Twelve of the patients exhibited additional cardiac disease requiring surgery: seven cases presented additional coronary artery disease, one mitral valve disease, one persistent ductus arteriosus, one an aneurysm of the right coronary artery, and two an atrial septal defect. We performed fistula closure either by ligating or transsecting the fistula as well as by closure of the fistula's drainage opening. Surgery and postoperative courses were uneventful in all patients. Most of the patients (93%) were in good clinical condition (NYHA I-II) after a mean follow-up period of 6.6 years (range 3-11). Fistula closure should be performed in patients who are symptomatic or who have a hemodynamic relevant shunt. In asymptomatic patients and small left-to-right shunt, fistula closure should also be performed to prevent later complications. Surgical fistula closure should be employed in patients with larger and more complex fistulae, especially if interventional therapy failed, and for patients with additional cardiac conditions that necessitate surgery.

Right pulmonary artery-to-left atrium communication: a rare cause of systemic cyanosis.

Direct communication between the right pulmonary artery and the left atrium is a rare congenital vascular malformation. The clinical diagnosis is difficult, and preoperative angiography is essential. We treated this anomaly successfully with surgery and the use of cardiopulmonary bypass in an 11-year-old boy. Surgery provides a complete cure for this anomaly.

Eleven-year follow-up after descending thoracic aorta replacement in a small child.

Eleven years after the prosthetic replacement of a hypoplastic thoracic aorta in a 3.5-year-old child, there was normal growth of the aortic arch and abdominal aorta without signs of restenosis. This case illustrates that growth of the aorta can be normal after replacement of its thoracic part in a growing child.

Development of pulmonary arteries after central aortopulmonary shunt in newborns.

BACKGROUND: Central shunt (CS) is frequently used to treat diminished pulmonary blood flow in newborns. We analyzed the impact of CS on the growth of the pulmonary arteries (PAs). METHODS: Twenty-two consecutive newborns underwent a CS procedure. In 15 newborns the preoperative angiograms and angiograms taken before undergoing anatomic or hemodynamic correction procedures were analyzed. The patients were divided retrospectively into two groups by the size of the PA in the preoperative angiogram: group I, patients with PAs more than 4 mm (n = 10), group II, PAs 4 mm or less (n = 5). To compare the development of the PAs in the groups, the Nakata index, McGoon ratio, and lower lobe indices were calculated from angiograms. RESULTS: The indices were significantly higher in group I before CS, but no differences was found between the groups before anatomic or hemodynamic correction. The postoperative Nakata indices and the McGoon ratios in the groups were higher when compared with preoperative values (group I, p = 0.037 and p = 0.013; group II, p = 0.043 and p = 0.043, respectively). The significant increase of the lower lobe indices only in group II (p = 0.043) suggests faster growth of the PA in this group. CONCLUSIONS: Optimal diameters of the CS promote growth of the PAs, which was confirmed by the increased Nakata and McGoon indices. The benefit in smaller PAs is greater.

Capillary leak syndrome in children who undergo cardiopulmonary bypass: clinical outcome in comparison with complement activation and C1 inhibitor.

OBJECTIVES: Capillary leak syndrome (CLS) is associated with significantly increased morbidity and occurs after cardiopulmonary bypass in children with congenital heart disease. We investigated the early clinical parameters that predict the development of CLS and examined the relationship between the presence of CLS and complement and contact activation and C1 esterase inhibitor (C1-INH) during and after bypass. DESIGN: In this prospective study we took serial serological measurements of the complement and contact system and C1-INH in a cohort of 27 infants before, during, and up to 96 h after open-heart surgery. RESULTS: Complement and contact activation and a decrease in C1-INH were measured in all infants during and after CPB. Ten infants developed CLS postoperatively. Younger age and longer bypass time were strongly correlated to the development of CLS. No relationship was found between the degree of hypothermia, weight, gender, or cross-clamp time. C1-INH concentration and activity were lower peri- and postoperatively in the CLS group. Infants with CLS had a more pronounced postoperative increase in the C5a and C3a levels, higher postoperative level of factor XIIa, and lower prekallikrein activity than those without CLS. CONCLUSION: Contact and complement activation occurs during cardiopulmonary bypass and contributes to CLS more frequently in infants of a younger age and with a prolonged bypass time. This activation and decrease in C1-INH was strongly expressed in the CLS group, and therefore early substitution of C1-INH may prevent CLS after open-heart surgery in high-risk infants.

Early experience with extracardiac Fontan operation.

BACKGROUND: The extracardiac Fontan (ECFO) operation has gained more widespread use over last decade. In this article we analyze our early experience with ECFO. METHODS: Thirty-three patients underwent ECFO at median age 4.1 years. Normothermic perfusion with the heart beating was used in 24 patients and cardioplegia in 7. Fenestration was not performed in the last 16 patients who underwent surgery without cardioplegia. RESULTS: The hospital mortality was 6% (2 patients). Necessity or duration of inotropic support, duration of mechanical ventilation, intensive care unit and hospital stay, and incidence of prolonged pleural effusions of patients operated on without cardioplegia were shorter and the rate of complications in these patients was lower than in patients who underwent cardioplegia. CONCLUSIONS: Our preliminary experience shows that ECFO can be performed in many patients with normothermic cardiopulmonary bypass and without cardioplegia and fenestration. Avoidance of cardioplegia seems to decrease postoperative morbidity. Incidence of early postoperative arrhythmias is low. Despite encouraging early results, longer follow-up is necessary to prove the real advantages of ECFO.