[Hypoplasia of trachea with tracheal bronchus as a complication of surgical correction of tetralogy of Fallot]. / Hypoplazie trachey s tracheálním bronchem jako prícina komplikací po korekci Fallotovy tetralogie.

A 10 months old infant underwent repair of tetralogy of Fallot with hypoplastic annulus of the pulmonary valve, diminutive pulmonary arteries, right aortic arch and left superior vena cava. The right ventricular outflow tract was reconstructed using a monocusp patch. The postoperative course was unfavourably influenced by respiratory complications due to tracheal bronchus and hypoplasia of trachea, which were not diagnosed preoperatively. Extreme emphysema of the right upper and middle lobes compromised haemodynamics. Repeated reoperations were required. The upper and the middle lobes of the right lung had to be resected, the hypoplastic trachea reconstructed with a pericardial patch and pulmonary homograft inserted. One year later, homograft had to be replaced and tricuspid annuloplasty performed for pulmonary and tricuspid regurgitation and right ventricular dilatation as a consequence of increased pulmonary artery pressure. Three years after the original surgery the patient remains in good clinical condition.

Resynchronization pacing is a useful adjunct to the management of acute heart failure after surgery for congenital heart defects.

The acute hemodynamic effect of atrioventricular (AV) and inter/intraventricular (IV) resynchronization accomplished by temporary pacing using multiple epicardial pacing wires was evaluated in 20 children (aged 3.4 months to 14.0 years) after surgery for congenital heart defects fulfilling the following criteria: (1) presence of AV and/or IV conduction delay, and (2) need for inotropic support. AV resynchronization (n = 13) was achieved by AV delay optimization during atrial synchronous right ventricular outflow tract pacing. IV resynchronization (n = 14) was accomplished by atrial synchronous pacing from the right ventricular lateral wall in 7 patients with right bundle branch block and normal AV conduction and by atrial synchronous multisite ventricular pacing in another 7 patients with previously performed AV resynchronization. Compared with baseline values, AV resynchronization resulted in an increase in arterial systolic, mean, and pulse pressures by 7.2 +/- 8.3% (p <0.01), 8.6 +/- 8.1% (p <0.005), and 6.9 +/- 13.5% (p = NS), respectively. IV resynchronization used either alone or added to previously performed AV resynchronization led to a pressure increase of 7.0 +/- 4.7%, 5.9 +/- 4.7%, and 9.4 +/- 7.8%, respectively (p <0.001 for all). The combined effect of AV and IV resynchronization resulted in a systolic, mean, and pulse pressure increase of 10.2 +/- 5.0% (range 4.0 to 19.1), 8.6 +/- 5.4% (range 0.8 to 14.8), and 15.2 +/- 8.5% (range 6.1 to 33.3), respectively (p <0.001 for all). The increase in systolic arterial pressure after IV resynchronization was positively correlated with the initial QRS duration (r = 0.62, p <0.05) and extent of QRS shortening (r = 0.66, p <0.05). In conclusion, resynchronization pacing led to a significant increase in arterial blood pressure and was a useful adjunct to the treatment of acute postoperative heart failure in patients with AV and/or IV conduction delay.

Hemodynamically optimized temporary cardiac pacing after surgery for congenital heart defects.

Disturbance of normal AV synchrony and dyssynchronous ventricular contraction may be deleterious in patients with otherwise compromised hemodynamics. This study evaluated the effect of hemodynamically optimized temporary dual chamber pacing in patients after surgery for congenital heart disease. Pacing was performed in 23 children aged 5 days to 7.7 years (median 7.3 months) with various postoperative dysrhythmias, low cardiac output, and/or high inotropic support and optimized to achieve the highest systolic and mean arterial pressures. The following four pacing modes were used: (1) AV synchronous or AV sequential pacing with individually optimized AV delay in 11 patients with first- to third-degree AV block; (2) AV sequential pacing using transesophageal atrial pacing in combination with a temporary DDD pacemaker for atrial tracking and ventricular pacing in three patients with third-degree AV block and junctional ectopic tachycardia, respectively, who had poor signal and exit block on atrial epicardial pacing wires; (3) R wave synchronized atrial pacing in eight patients with junctional ectopic tachycardia and impaired antegrade AV conduction precluding the use of atrial overdrive pacing; (4) Atrio-biventricular sequential pacing in two patients. Pressures measured during optimized pacing were compared to baseline values at underlying rhythm (13 patients with first-degree AV block or junctional ectopic tachycardia) or during pacing modes commonly used in the given clinical situation: AAI pacing (1 patient with slow junctional rhythm and first-degree AV block during atrial pacing), VVI pacing (2 patients with third-degree AV block and exit block and poor sensing on epicardial atrial pacing wires) and dual-chamber pacing with AV delays set to 100 ms (atrial tracking) or 150 ms (AV sequential pacing) in 7 patients with second- to third-degree AV block and functional atrial pacing wires. Optimized pacing led to a significant increase in arterial systolic (mean) pressure from 71.5 +/- 12.5 (52.3 +/- 9.0) to 80.5 +/- 12.2 (59.7 +/- 9.1) mmHg (P < 0.001 for both) and a decrease in central venous (left atrial) pressure from 12.3 +/- 3.4 (10.5 +/- 3.2) to 11.0 +/- 3.0 (9.2 +/- 2.7) mmHg (P < 0.001 and < 0.005, respectively). In conclusion, several techniques of individually optimized temporary dual chamber pacing leading to optimal AV synchrony and/or synchronous ventricular contraction were successfully used to improve hemodynamics in patients with heart failure and selected dysrhythmias after congenital heart surgery.

[Aortic reconstruction in neonates with hypoplastic left heart syndrome] . / Rekonstrukce aorty u novorozencu se syndromem hypoplastického levého srdce.

The surgical technique and tactics of the Norwood operation in neonates with hypoplastic left heart syndrome represent a surgical challenge. The Norwood operation was performed from the midline sternotomy approach, in extracorporeal circulation and deep hypothermic circulatory arrest was used for reconstruction of the hypoplastic aorta. Operation consisted of reconstruction of the "neoaorta" and the aortic arch from the original hypoplastic ascendent aorta, pulmonary trunk and a patch cut from a pulmonary homograft or pericardium, excision of the atrial septum and an arterial shunt from a Goretex vascular graft 3.5 or 4 mm in diameter. In patients with well developed aortic arch it was possible to reconstruct the aorta using Damus-Kaye-Stansel operation without circulatory arrest. Out of 12 operated patients with this defect, two (16.7%) died during the early postoperative period, one patient died late. The postoperative course was often complicated. In 6 (50.0%) patients the second step of Norwood operation, the bidirectional cavopulmonary anastomosis, was performed without mortality. According to our experience, it was necessary to prepare patients adequately before the first surgery. Perfect reconstruction of the aorta and a well functioning shunt had the crucial significance.

[The value of magnetic resonance tomography (MRT) for evaluating ventricular and anastomotic functions in patients with an extra- or intracardiac total cavopulmonary connection (TCPC)-modified Fontan operation]. / Wertigkeit der Magnetresonanztomographie (MRT) zur Beurteilung der Ventrikel- und Anastomosen-Funktion bei Patienten mit extra- oder intrakardialer totaler cavopulmonaler Anastomose (TCPC)-modifizierte Fontan-Operation.

PURPOSE: To evaluate different MR methods (ventricle and flow measurements) for the postoperative follow-up of hemodynamics in patients with extra- or intracardial TCPC. MATERIALS AND METHODS: Twenty-eight consecutive patients (14 female, 14 male) within the ages of two to thirty-eight years were examined using a 1.5 T Gyroscan ACS-NT scanner (Philips, Best, Netherlands). 7 patients had an extracardial (eTCPC), and 21 an intracardial (iTCPC) tunnel. The calculation of the ventricular function and muscle mass was performed using "multislice-multiphase" technique by summing up the end-diastolic and end-systolic areas; the flow measurements were evaluated by phase shift velocity mapping in the superior vena cava (SVC), inferior vena cava (IVC), right (RPA) and left (LPA) pulmonary artery. Besides peak and mean velocity, the mean and maximal flow volumes (ml/min) were calculated. RESULTS: Ejection fraction (EF) of the functionally single ventricle was within the normal range (mean 57%) in 22/28 patients while mean muscle mass was elevated in the group with eTCPC (mean 121 g/m2). The mean flow volumes and the peak velocities in all vessels were higher in the group with iTCPC as compared to the one with eTCPC. Clinically relevant retrograde flows in the IVC were only found in the group with iTCPC (7/21), as well as a significant predominant flow distribution towards the RPA (p < 0.05; Wilcoxon signed-rank test); in the group with eTCPC towards the LPA (n.s.). CONCLUSIONS: MRI is a useful method for the assessment of ventricular function and muscle mass in the follow-up after the modified Fontan operation. MRI flow measurements additionally provided clinically relevant information about the hemodynamics in Fontan patients.

[Initial experience with surgical treatment of tracheal stenosis in small children using extracorporeal circulation]. / Prvé zkusenosti s chirurgickým resením stenózy trachey u malých detí s pouzitím mimotelního obehu.

Severe tracheal stenosis represents a life threatening malformation which necessitates early surgery. Two patients aged one and two years, respectively, were followed-up for signs of congenital stridor. Following respiratory infection both children became critically ill with severe dyspnoea necessitating intubation and artificial ventilation. In the first patient, echocardiography, tracheobronchoscopy and other investigations revealed a pulmonary artery sling with tracheal compression and hypoplasia of the whole trachea. In the second child, presence of a short local tracheal stenosis was found, the cause of which could not be clarified. In the patient with the pulmonary sling, resection and reimplantation of the anomalous left pulmonary artery was performed first. In both children, however, surgical reconstruction of the lower airways was necessary. Surgery was performed from a midline sternotomy approach in extracorporeal circulation. The hypoplastic trachea with circular rings in the first child was enlarged with a pericardial patch. In the second child, the local tracheal stenosis was resected and a direct anastomosis of the trachea was performed. In both patients, transient formation of granulations was observed. Both children, however, survived and their clinical condition remains good 18 and 9 months, respectively, after surgery. Tracheobronchoscopic controls show very good result. Our experience confirms the possibility of successful surgical reconstruction of lower airways in young children using extracorporeal circulation. Good interdisciplinary cooperation between the surgeon and other specialists is an important prerequisite of good surgical results.

[Plication of the diaphragm--a method of surgical treatment of diaphragmatic paralysis in neonates and infants after heart surgery]. / Plikace bránice--metoda chirurgické lécby parézy bránice u novorozencu a kojencu po kardiochirurgických operacích.

The cause of paresis of the diaphragm after cardiosurgery is damage of the phrenic nerve. The diagnosis of paresis is based on X-ray examination, sonography and electromyography of the diaphragm. Plication of the diaphragm is indicated only in those children with paresis of the diaphragm who develop during spontaneous ventilation severe respiratory insufficiency. In the Cardiocentre of the Faculty Hospital Prague-Motol between 1983 and 1996 of 5333 children operated on account of heart disease 29 children were subjected to plication of the diaphragm, incl. five where the operation was made during the neonatal stage (17%), 20 in infant age (69%) and four were older than one year (14%). By the third day after plication 9 children (38%) could be disconnected from the respirator, by the 5th day 20 children (70%) by the 7th day 22 children (75%). In neonates and infants with postoperative paresis of the diaphragm, where spontaneous ventilation cannot be induced, plication of the diaphragm is according to the authors the method of choice. It is a rapid and safe surgical operation which reduces the period of artificial ventilation and its complications.

Fatal infantile hypertrophic cardiomyopathy secondary to deficiency of heart specific phosphorylase b kinase.

We describe here a male infant with a rare form of glycogenosis caused by deficiency of heart specific phosphorylase b kinase. The disease phenotype was characterized by severe glycogenosis restricted to the heart muscle with secondary rapidly progressive hypertrophic cardiomyopathy causing death at the age of 47 days.