[The technique of outflow tract reconstruction in patients with tetralogy of Fallot influence the morbidity 3 decades after repair]. / Die Technik der Ausflussbahnrekonstruktion bei Fallotscher Tetralogie beeinflusst die Morbidität der Patienten nach drei Jahrzehnte nach einer Korrekturoperation.

The purpose of this study was to examine long-term results of different surgical techniques in patients with tetralogy of Fallot considering their morbidity. We analyzed the data of 74 patients 24.5 +/- 3 years after surgical repair in childhood to evaluate their clinical status, maximal exercise capacity, medication and frequency of reoperations. We compared two groups of patients according to the surgical techniques employed: 1) TAP group (Trans anular Patch, n = 41) in which ventricular septal defects were closed with a Dacron patch, the right ventricular outflow was reconstructed by resection of the partial extension of the infundibular septum and transanular patch repair was performed because of hypoplastic pulmonary valve. 2) nonTAP group (33) in which no transanular patch repair was necessary. Most of the patients described their health as "good". 94% of the nonTAP group and 71% of TAP group were in NYHA class I. The rest were in NYHA class II. Despite the good clinical classification we found a reduced cardiopulmonary exercise capacity in all patients. More than 50% in the TAP group took medicine because of congestive heart failure and/or arrhythmia, which was present 3-times more often compared with the nonTAP group. Furthermore, 50% of TAP group patients had at least one reoperation during the follow- up: by comparison 5-times more often than the nonTAP group. These data show that the long-term outcome and morbidity of the patients after repair is closely related to the type of the surgical technique employed.

Pregnancy in congenital cardiac disease: an increasing challenge for cardiologists and obstetricians -- a prospective multicenter study.

OBJECTIVES: Aim of this study was to assess the occurrence of pregnancy-related complications of mother and child during pregnancy, delivery and puerperium in women with CCD prospectively. STUDY DESIGN, POPULATION: This prospective multicenter study included 122 pregnancies in 106 women with CCD (72 with, 34 without previous cardiac surgery). Patient age was 17-44, median 26 years. Cardiac and non-cardiac complications, mode of delivery, abortion, and CCD of the newborn were assessed. RESULTS: Initially all women were in Functional Class I or II. Worsening during pregnancy occurred in 25.5% (n=27), mainly during the second and third trimester. Significant problems due to bleeding, hypertension, rhythm disturbances, endocarditis, liver congestion, increasing cyanosis or death, occurred in 11.3%. Twelve per cent of deliveries were premature. Five women had therapeutic abortion, nine spontaneous abortions, nine preterm births, and one intrauterine death. Seventy-nine per cent (n=85) delivered spontaneously; 21.3% (n=23) had caesarean section. Of the 111 live born children, 5.4% (n=6) had a CCD. CONCLUSIONS: Most women with CCD and a good functional class before pregnancy tolerate pregnancy without major problems. However, pregnancy may induce serious cardiac and obstetric complications. The specific risks require an individualized multidisciplinary patient-management by experienced physicians.

The pathogenesis of heart failure in infants with congenital heart disease.

BACKGROUND: The clinical symptoms of heart failure in infants with left-to-right shunts are thought to be explained by well-known hemodynamic disturbances such as pulmonary hypertension and overcirculation, but previous studies have not, thus far, found the expected correlations with hemodynamic and clinical parameters. Based on the neurohormonal model of heart failure, we hypothesised that the clinical symptoms of infants with left-to-right shunts are also related to neurohormonal disorders. METHODS: We compared various neurohormonal and hemodynamic parameters measured invasively in 70 infants with left-to-right shunts to the respiratory rate and gain in weight over a corresponding period of time. Heart rate correlated significantly with respiratory rate (r = 0.62***, p < 0.001) and gain in weight (r = -0.31*, p = 0.015), but more conventional measures of severity, such as the ratio of pulmonary to systemic flows, failed to show comparable correlations with clinical symptoms. Respiratory rate was related to levels of norepinephrine (r = 0.47***, p < 0.001) and plasma renin activity (r = 0.65***, p < 0.001). The important impact of autonomic imbalance on respiratory rate was underlined by an analysis of variability of heart rate in 26 infants that showed significantly reduced values for the domains of time and frequency. We were not able to find a conclusive multiple regression model with which to explain the symptom "failure to thrive". CONCLUSIONS: A increased heart rate, reduced variability in heart rate, and elevated levels of norepinephrine and renin are significant predictors of clinical symptoms such as tachypnea in infants with congenital cardiac malformations. The neurohormonal hypothesis, in which heart failure is interpreted not only as a hemodynamic derangement but also as a neurohormonal disorder, may be valid for infants with congenital cardiac malformations.

Propranolol treatment of congestive heart failure in infants with congenital heart disease: The CHF-PRO-INFANT Trial. Congestive heart failure in infants treated with propanol.

AIM: Infants with congenital heart disease and left-to-right shunts may develop significant clinical symptoms of congestive heart failure in spite of therapy with digoxin and diuretics. We investigated the effects of beta-blockade in infants with severe heart failure. METHODS AND RESULTS: We performed a prospective, randomized, open monocenter trial in infants treated with digoxin and diuretics (n=10) in comparison to 10 infants receiving additional beta-blocker therapy. After 17 days on average beta-blocker treated infants (propranolol:1,6 mg/kg/day) improved significantly with respect to Ross heart failure score (3.3+/-2.3 vs. 8.3+/-1.9, P=0.002), lower renin levels (338+/-236 vs. 704+/-490 microU/l, P=0.008) and lower mean heart rates in Holter ECG (118+/-10 vs. 142+/-11 beats/min, P<0.001). While digoxin and diuretic treated infants had unchanged mean heart rate (149+/-8 vs. 148+/-10 beats/min), less decrease of symptoms (Ross Score: 8.5+/-1.7 vs. 6.8+/-2.3, P=0.02) but a significant increase of renin levels (139+/-102 vs. 938+/-607 microU/l, P=0.001). CONCLUSION: Additional propranolol treatment but not digoxin and diuretics alone can effectively reduce clinical symptoms of heart failure in infants with congenital heart disease, who suffer from increased neurohormonal activation.

Activity of the renin-angiotensin-aldosterone and sympathetic nervous system and their relation to hemodynamic and clinical abnormalities in infants with left-to-right shunts.

We studied neurohormonal, clinical and invasively measured hemodynamic data of 47 infants with left-to-right shunts and varying degrees of congestive failure. When referred to a clinical heart failure score, plasma renin activities (r=0.71) and norepinephrine levels (r=0.43) are significantly increased. Arterial hypotension seems to be the hemodynamic trigger of renin release (r=-0.72), but not decreased systemic cardiac index (r=-0.43), the magnitude of the left-to-right shunt (r=0.33) or a reduced ejection fraction (r=0.12). These data indicate neurohormonal activation in infants with left-to-right shunts with preserved myocardial function is similar to the activation in adults with heart failure secondary to myocardial pump failure. These findings have to be considered for optimal medical treatment of these infants with angiotensin-converting enzyme inhibitors or beta-blockers.

Pathogenetic mechanisms of venous congestion after the Fontan procedure.

BACKGROUND: The hemodynamic status after a Fontan type procedure for definitive palliation of functionally univentricular hearts is dominated by a high central venous pressure, which seems to be one of several factors responsible for venous congestion appearing as a frequent complication in the early and late postoperative course. The purpose of our study was to find other hemodynamic parameters correlating with the presence of venous congestion and effusions in these patients. METHODS: We compared the hemodynamic data of 18 patients who had an uneventful long-term course after a Fontan type procedure with the respective data of 10 patients who developed symptoms of venous congestion in the immediate postoperative period. Based on a theoretical model, we developed an algorithm to calculate mean hydrostatic capillary pressure from mean arterial pressure, systemic vascular resistance index and central venous pressure. RESULTS: Pulmonary vascular resistance index (2.1 +/- 1.0 mmHg L-1 min m2), mean left atrial pressure (9.7+/-4.0 mmHg) and cardiac index (3.6+/-0.6 l/min/m2) are mainly normal in patients with venous congestion in the immediate postoperative period, but mean hydrostatic capillary pressure is significantly higher compared to patients without venous congestion (24.3+/-3.1 vs 18.3+/-4.0 mmHg). Lower mean hydrostatic capillary pressures in these patients are due to a highly significant increase of systemic vascular resistance index (18.6+/-4.2 versus 33.6+/-6.6 mmHg L-1 min m2) and a concomitant decrease of cardiac index to 2.4+/-0.3 l/min/m2. CONCLUSIONS: The increase of mean hydrostatic capillary pressure, caused by high central venous pressures but also by relatively low systemic vascular resistance indexes, seems to be the hemodynamic key parameter responsible for venous congestion and effusions in patients after a Fontan type procedure in the immediate postoperative period.

Effectiveness of low dose captopril versus propranolol therapy in infants with severe congestive failure due to left-to-right shunts.

UNLABELLED: To evaluate the therapeutical effects of the angiotensin converting enzyme inhibitor Captopril to the beta-blocker Propranolol in infants with congestive failure due to pulmonary overcirculation, we retrospectively analysed clinical, neurohormonal and hemodynamic data in 22 infants, 11 of whom were treated with Captopril (Group 1), 11 with Propranolol (Group 2). Age, weight, number of palliative operations, plasma renin activities and pulmonary to systemic flow ratios (3.5 vs. 3.5) were not significantly different prior to Captopril or Propranolol therapy. If treatment with digoxin and diuretics did not succeed, the infants were additionally treated with Captopril (1 mg/kg) for a mean of 7.4 months, or with 1.9 mg/kg Propranolol for 9.2 months. RESULTS: 1 mg/kg Captopril did not effectively suppress angiotensin converting enzyme in the steady state at trough level (92+/-52 vs. 87+/-50 nmol/min/ml). In the Propranolol group, the clinical heart failure score (2.6+/-1.5 vs. 7. 4+/-2.5) and plasma renin activities (14+/-10 vs. 101+/-70 ng/ml/h) were significantly lower, compared to the Captopril group. Length of hospital stay (23+/-9 vs. 52+/-24 days) was lower and weight gain (126+/-38 vs. 86+/-84 g/week) was higher within 3 months after starting Propranolol therapy. Significantly lower left atrial pressures (6.2+/-2.2 vs. 13.4+/-9.2 mmHg) and lower endiastolic ventricular pressures (7.6+/-2.5 vs. 12.6+/-4.0 mmHg) during pre-operative cardiac catheterization indicated a better diastolic ventricular function under chronic Propranolol treatment. CONCLUSION: Although high dose Captopril was not evaluated in this study, when compared to patients on low Captopril dosages, infants who received Propranolol treatment showed improvement in heart failure scores, shorter lengths of hospital stay, lower plasma renin activities and better diastolic ventricular functions.

Beta-blocker therapy of severe congestive heart failure in infants with left to right shunts.

We report on the clinical and neurohumoral effects of adding low-dose propranolol to conventional therapy with digoxin and diuretics in 6 infants with severe congestive heart failure due to large left-to-right shunts. A significant decrease in heart failure scores and a decrease of the highly activated renin-angiotensin-1 aldosterone system by approximately 70% strongly suggests a beneficial effect of this new therapeutic approach.

[Pathogenesis of venous congestion symptoms after Fontan operation]. / Zur pathogenese der Stauungssymptomatik nach Fontanscher Operation.

To evaluate a possible common pathogenetic denominator, we compared hemodynamic data of 18 patients who had an uneventful long-term course after a Fontan procedure, with the respective data of patients who developed symptoms of central venous congestion either in the immediate postoperative period (n = 10) or during late follow-up (n = 6). We found a coincidence of increased early postoperative venous pressures (CVP; 17.1 +/- 2.9 mm Hg) with relatively high cardiac indices (3.6 +/- 0.6 l/min.m-2) as compared to 2.4 l/min.m-2 in the group of patients with a symptom-free long-term course but no significant difference in total pulmonary resistance between the two groups. The increased CVP (17.2 +/- 2.9 mm Hg) in patients with late chronic central venous congestion is primarily due to increased total pulmonary resistance (552 +/- 131 dyn s/cm5.m-2). Both groups of patients with central venous congestion display a ratio of systemic to total pulmonary resistance lower than 4.5 whereas symptom-free patients have a significantly higher resistance ratio (6.8 +/- 2.3) and a highly significant increase in peripheral resistance to values of 2687 +/- 527 dyn s/cm5.m-2 as compared to 1486 +/- 340 dyn s/cm5.m-2 in the early postoperative group. Correspondingly, mean arterial pressure of the symptom-free patients is significantly elevated (93 +/- 11 mm Hg) as compared to a control group (81 +/- 11 mm Hg). Based on our theory an increase in systemic arterial resistance may lead to a fall in mean capillary filtration pressure and therefore counteract central venous congestion. To support this, we briefly present cases where pharmacologic enhancement of systemic arterial resistance was effective in the treatment of venous congestion whereas pharmacologic lowering of systemic resistance induced venous congestion.

[Anesthesiologic aspects of pregnancy and delivery in a patient following a modified Fontan procedure ]. / Anästhesiologische Aspekte der Schwangerschaft und Entbindung bei einer Patientin nach modifizierter Fontan-Operation.

The number of patients with congenital cyanotic heart disease who reach child-bearing age is increasing. This is partly a consequence of the high long-term survival and the haemodynamic benefits resulting from the Fontan procedure, which is used for the definitive palliation of such cyanotic heart disease as tricuspid atresia and single ventricle. However, so far little experience has been recorded with pregnant patients who have undergone right ventricular exclusion procedures. The particular physiology of a univentricular heart and a passive, non-pulsatile blood flow through the lungs has significant implications for the anaesthetic obstetric management of these patients. We report a case of successful pregnancy and caesarean delivery after a modified Fontan procedure. CASE REPORT. The patient was a 30-year-old pregnant woman with a singleton pregnancy. At the age of 20, after four palliative shunt operations, she had undergone a modified Fontan operation due to tricuspid atresia with a single ventricle, d-transposition of the great arteries, pulmonary atresia and a single atrium. Following the Fontan repair, she initially suffered from intermittent Wolff-Parkinson-White syndrome and isorhythmic AV dissociation. The pregnancy was uneventful, and caesarean section was scheduled for 32 weeks' gestation. Because of the increased risk of thrombosis, the patient was treated with s.c. heparin preoperatively; for this reason, epidural anaesthesia was excluded, though it may otherwise be preferred for such patients. Amoxicilline was used to prevent endocarditis. At the date of caesarean delivery her body weight was 54 kg and boy height, 155 cm. Before induction of anaesthesia, a central venous and a radial artery catheter were placed for invasive pressure monitoring. An exaggerated left lateral tilt position was used to avoid aortocaval compression. After careful preoxygenation, anaesthesia was induced with 24 mg etomidate, 1.5 mg norcuronium, and 75 mg succinylcholine. Halothane 0.5-0.7% in oxygen was used during the first few minutes of surgery. Central venous pressure under mechanical ventilation was 20 mmHg, while the heart rate varied between 70 and 90 bpm. Delivery was accomplished 8 min after the induction of anaesthesia. The Apgar scores after 1 and 5 min were 9 and 10, respectively. Anaesthesia was continued with fentanyl, midazolam and nitrous oxide 50%. The remainder of surgery was unevenful. The child is now 5 years old and healthy. The mother has a near-normal activity level and does not need any help to care for her child. DISCUSSION. After a modified Fontan repair, i.e. atriopulmonary or total cavopulmonary anastomosis, the pulsatile pulmonary blood flow is converted to a passive, non-pulsatile blood flow that depends critically both on the pressure gradient between right (RAP) and left atrial pressure (LAP) and on pulmonary vascular resistance (PVR). Thus, the maintenance of an adequate transpulmonary pressure gradient and avoidance of an increase in PVR are of major importance for the obstetric anaesthetic management in patients who have undergone right ventricular exclusion procedures. Impairment of venous return caused by slight caval compression or high airway pressure may reduce cardiac output more critically than in patients with a normal circulation. CONCLUSION. This case demonstrates that the haemodynamic consequences of pregnancy and of caesarean delivery under general anaesthesia can be tolerated in post-Fontan patients despite the absence of a contractile pulmonary ventricle.

Amiodarone in a newborn with ventricular tachycardia and an intracardiac tumor: adjusting the dose according to an individualized dosing regimen.

We report the successful management of recurrent ventricular tachycardias in a newborn suffering from an intracardiac tumor. Amiodarone was the only agent able to control the tachycardias and did so as long as an individually titrated plasma concentration above 0.8 mu mol/L was maintained. Because no therapeutic plasma concentration has been defined in children and no kinetic studies are available in this population, we optimized the dosing regimen based on a computer simulation, taking into account the pharmacokinetic parameters of the patient and the individual concentration-effect relation.

[Normal pregnancy duration after maternal Fontan operation of univentricular heart]. / Ausgetragene Schwangerschaft nach maternaler Fontan'scher-Operation bei univentrikulärem Herzen.

Up to now pregnancy in patients with a previous Fontan operation for definitive palliation of a univentricular heart has been regarded as contraindicated. Two cases of a pregnancy after Fontan operation and univentricular heart were published in the literature. In a single case a successful delivery of the fetus could be achieved. The presented case is the third published pregnancy after Fontal operation and the second with a successful fetal outcome. The 30 years old patient was born with a univentricular heart of right ventricular type with tricuspid and pulmonary atresia and persisting arterial duct. After bilateral Blalock Taussig anastomoses (1966) and modified Waterston-Cooley-anastomosis (1974) a primary existing cyanosis could be improved. The cyanosis was completely abolished after definitive repair with the Fontan operation at the age of 17 (1980). The course of pregnancy and its surveillance is reported. In the 32nd week of gestation cesarean section had to be performed because of threatening cava compression. A healthy female fetus of 1275 g was delivered. The mother's postoperative recovery was uneventful. Meanwhile the neonate and the mother have been discharged and are in good clinical condition.

Histopathologic abnormalities of the sinus node compared with electrocardiographic evidence of sinus node dysfunction after the modified Fontan operation: an autopsy study of 14 cases.

Autopsy specimens from 14 patients who had undergone a modified Fontan operation were evaluated to correlate the extent of histopathologic disruption of the sinus node with electrocardiographic findings of sinus node dysfunction. Patients with sinus node dysfunction (n=7) and those without (n=7) were similar in age, complexity of cardiac malformation, and number of postoperative days at time of death. The degree of fibrosis, local hemorrhage, necrosis, lymphocytic infiltration, and focal calcification of the sinus node and perinodal tissue was also similar in both groups. These findings, which showed a comparable amount of sinus node disruption in patients with normal sinus rhythm and in those with sinus node dysfunction, indicate a lack of correlation between the extent of histopathologic abnormality of the sinus node and electrocardiographic evidence of sinus node dysfunction.

The modified Fontan operation for children less than 4 years old.

Of 500 patients who had a modified Fontan operation at this institution between 1973 and 1987, 54 (33 boys and 21 girls) were less than 4 years old. This retrospective study related preoperative clinical and hemodynamic data to subsequent survival. Twenty patients less than 4 years old had tricuspid atresia, 13 had double inlet ventricle and 21 had other complex heart defects. There were 14 early deaths (less than 30 days after operation) and 6 late deaths. Multivariate analysis of survival for the entire group of 500 patients revealed the following factors to be significantly associated with poorer survival: absence of tricuspid atresia (p = 0.011), asplenia (p less than 0.001), age less than 4 years at operation (p = 0.042), atrioventricular valve dysfunction (p = 0.017), early calendar year of operation (p less than 0.001) and the presence of either one or more of the following: left ventricular ejection fraction less than 60%, mean pulmonary artery pressure greater than 15 mm Hg and pulmonary arteriolar resistance greater than 4 U.m2 (p less than 0.001). On the basis of this study of 500 patients, age less than 4 years at operation appears to be an independent risk factor for poorer survival after the modified Fontan operation.