[Noninvasive assessment of wall stress related velocity of circumferential fiber shortening as an index of left ventricular contractility in children]. / Nichtinvasive Bestimmung des Kontraktilitätsindex "wandspannungsbezogene zirkumferentielle Verkürzungsgeschwindigkeit des linken Ventrikels" bei Kindern.

Assessment of the myocardial contractility in terms of the velocity of circumferential fiber shortening appropriate to the actual left ventricular endsystolic wall stress requires endsystolic pressure measurement usually done invasively. But for noninvasive evaluation of this parameter, we elaborated an algorithm to derive the endsystolic pressure in the ascending aorta from oscillometric blood pressure measurements. In 99 infants, children, adolescents, and young adults (1 day-37 years, median 5.5 years) we performed direct pressure recordings in the ascending aorta while measuring the arterial blood pressure at the upper arm by the Dinamap 8100 Blood Pressure Monitor. If measured directly, endsystolic (ESP(direct)) and mean aortic pressure (MAP(direct)) correlated well: ESP(direct)) = 1, 04 * MAP(direct))-2.18; r(2) = 0.91; s(y.x.) = 5.1 mm Hg. Comparison between the endsystolic and the mean arterial pressure (MAP(Dinamap) resulted in: ESP(direct) = 1.19 * MAP(Dinamap)-4.8; r(2) = 0.74; s(y. x.) = 8.3 mm Hg. In 52 patients this equation was used to derive the endsystolic pressure from the mean arterial pressure. Then the endsystolic wall stress was determined using the calculated (ESSm(Dinamap)) as well as the directly measured endsystolic pressure (ESSm(direct)): mean difference (ESSm(Dinamap) - ESSm(direct)) = -2.1 kdyn/cm(2); 95% confidence limits: -16.2 to 12. 1 kdyn/cm(2); linear regression: ESSm(direct = 1.07 * ESSm(Dinamap) - 2.22; r(2) = 0.91; s(y.x.) = 7.1 kdyn/cm(2). In n = 12 infants with complex heart defects and severe congestive heart failure due to pulmonary hyperperfusion the contractility was monitored noninvasively to assess the effects of propranolol (1.5 to 2 mg/kg/day) given complementary to digoxin and diuretics. The advantage of noninvasive assessment of the contractility in clinical routine was confirmed by the result that long-term propranolol does not impair myocardial contractility in this setting.

Radiofrequency catheter ablation of right ventricular tachycardia late after repair of congenital heart defects.

BACKGROUND: Ventricular arrhythmias after repair of congenital heart defects are a common finding and possibly contribute to sudden death in these patients. Optimal antiarrhythmic management has not yet been defined. METHODS AND RESULTS: The study population consisted of 16 patients in whom ventricular arrhythmias occurred 11 to 42 years after complete surgical repair of congenital heart defects. Fifteen patients had a history of symptomatic sustained or nonsustained ventricular tachycardia, and 1 had frequent nonsustained ventricular tachycardia. The diagnostic mapping procedure to identify the origin of the arrhythmia included pace mapping during sinus rhythm, activation mapping, and pacing interventions during ventricular tachycardia. Catheter ablation was carried out by means of radiofrequency energy in the temperature-controlled mode. The follow-up period was 6 to 33 months (mean, 16 months). A right ventricular origin of the tachycardia in the surgically corrected area could be determined in all patients. Catheter ablation was carried out without complications. Immediate noninducibility was achieved in 15 of the 16 patients. One patient in whom the tachycardia was again inducible at repeat stimulation 1 week later was successfully treated with amiodarone. Eleven patients were taken off antiarrhythmic drugs. During follow-up, none of them had a recurrence of the tachycardia that had been ablated. CONCLUSIONS: In patients with symptomatic or frequent ventricular tachycardia late after complete surgical repair of congenital heart defects, catheter ablation by means of radiofrequency energy is feasible and safe and thus might be taken into consideration for these patients. Short-term follow-up results are promising.

[Quantification of postoperative pulmonary valve insufficiency: severity and clinical symptoms]. / Quantifizierung der postoperativen Pulmonalinsuffizienz: Schweregrad und klinische Symptomatik.

Surgical treatment of pulmonary stenosis may lead to inevitable valvular incompetence. The hemodynamic and clinical significance of post-operative pulmonary insufficiency (PI) is uncertain. In patients presenting cardiomegaly and reduced exercise tolerance reoperation may be considered. However, pulmonary valve replacement remains controversial. In order to elucidate the relevance of PI in the long-term post-operative course, quantitative data of PI were compared with chest radiographs and the physical condition. Thirty-one patients with a mean age of 18.5 years (3-36 years) were studied. Twenty-two patients had surgical correction of Tetralogy of Fallot (TOF) and nine had commissurotomy of pulmonary valve stenosis (PS). Catheterization was performed, on average, 12.9 years (2-29 years) after operation in 68% of cases with an interval of more than 10 years. PI was quantitated by digital roentgen densitometry. Regurgitant fraction (RGF) ranged between 13-61%, according to a right ventricle volume load index (VBI) of 1.15-2.6 (ratio of total to effective stroke volume). Twenty of 31 patients (12 TOF, 8 PS) had PI as the only significant lesion. VBI (1.15-2.6) correlated with the cardio thoracic ratio (0.50-0.64), r = 0.74. All patients were in good physical condition. 11 actively took part in sports: all of the eight patients studied by ergometry met normal conditions. Four patients had antiarrhythmic medication. Eleven of 31 patients had PI and additional abnormalities: tricuspid insufficiency (4), right ventricular pressure overload (5), ventricular septal defect (1), depressed left ventricular function (5), and aortic insufficiency (3).(ABSTRACT TRUNCATED AT 250 WORDS)

Transposition of the great arteries with straddling tricuspid valve. Report of two rare cases with acquired subaortic stenosis after main pulmonary artery banding.

The clinical, hemodynamic, angiocardiographic, and postmortem findings of a previously unreported type of subaortic stenosis are presented in two patients who also had straddling tricuspid valve and transposition of the great arteries. The subaortic stenosis became apparent after banding of the main pulmonary artery and was due to hypertrophy of a probably abnormally positioned moderator band resulting in a double-chambered right ventricle. Fibrous tissue accumulation at the stenotic os infundibuli also contributed to the subaortic obstruction. Both patients had situs solitus of the atria. Patient 1 had ventricular inversion (L-loop ventricles) and atresia of the right-sided mitral valve. Patient 2 had normally positioned ventricles (D-loop) and two atrioventricular valves. The presence of a large left ventricle and a small right ventricle in the angiocardiogram led to the erroneous diagnosis of a single left ventricle with an infundibular outlet chamber in both patients. Consequently, the subaortic obstruction was thought preoperatively to be at the site of a restrictive bulboventricular foramen. Patient 1 died 36 hours after placement of a valved conduit from the left ventricle to the descending aorta. Patient 2 was operated on successfully and the surgical procedures performed are described.

[Lung sequestration as a cause of acute cardiac decompensation in a 3-week-old newborn infant]. / Lungensequester als Ursache einer akuten kardialen Dekompensation bei einem 3 Wochen alten Neugeborenen.

A 3 week old neonate developed congestive heart failure after the operation of an omphalocele. The clinical aspect first suggested to us a persistent ductus arteriosus. Cardiac catheterisation then revealed a bronchopulmonary sequestration, a rare congenital malformation. Children usually become symptomatic with chronic respiratory tract infections, although there are also asymptomatic courses. Only a few cases are reported with congestive heart failure being the initial symptom. Many patients show additional malformations--so did our baby with an omphalocele and a mild peripheral pulmonary stenosis. Once the diagnosis is made, resection or lobectomy is the therapy of choice. In the preoperative diagnosis angiography is mandatory to demonstrate the abnormal vascular supply.

[Emergency treatment of arrhythmias in neonates and infants]. / Notfallbehandlung von Herzrhythmusstörungen im Neugeborenen- und Säuglingsalter.

Emergency treatment of cardiac arrhythmias was required in 41 newborn and infants aged two days to 9 months (mean 77 days) from July 1977 until September 1981. Heart defects were present in 27 (65.8%). Invasive electrophysiological studies were performed in all patients. The different types of arrhythmias were: bradyarrhythmias in 9 (21.9%): bradycardia to cardiac arrest (5), congenital complete AV-block (3), postoperative complete AV-block (1). Tachyarrhythmias in 32 patients (78.1%): reentry through accessory connections (21), congenital atrial flutter (6), ventricular flutter/fibrillation (3), and AV-nodal tachycardia (2). Overdrive atrial or ventricular stimulation with a consecutive series of 15-20 impulses of 5-10 Volts abolished arrhythmic attacks in 22 patients including 4 in whom prior digitalization had no effect. In two other patients overdrive pacing achieved sinus rhythm only after i.v. Propafenon. In 4 further patients 36.2 to 63.8 mg/m2 i.v. Propafenon and in 4 other patients DC synchronized cardioversion with 1 to 3 Wsec/kg restored a normal heart rate. The 3 patients with congenital complete heart block died, one despite permanent pacing. Oral Propafenon therapy with 300 mg/m2 die in three divided doses following emergency therapy of tachyarrhythmias was discontinued in patients without arrhythmias after 1 year on drug therapy. There was no relapse after a mean follow-up period of 1.9 years. Only patients with congestive heart failure due to cardiac defects needed additional digitalisation. Thus, in our experience antiarrhythmic drug therapy with Propafenon was more effective in this age group than digitalization.

[Propafenon therapy of arrhythmias in infancy and childhood (author's transl)]. / Propafenon in der Behandlung von Herzrhythmusstörungen im Säuglings- und Kindesalter.

The therapeutic dose range of propafenon was studied in 28 infants and children aged 5 days to 15.2 years (mean 8.8 years) with the following cardiac arrhythmias: paroxysmal tachycardia (20) atrial flutter (5) ventricular extrasystoles (2) and junctional tachycardia (1). With the intravenous administration of the drug in a dosage of 1.03-3.2 mg/kg/d (mean 2.28 mg/kg/d) in patients less than 15 kg and of 0.71-2.06 mg/kg/d (mean 1.26 mg/kg/d) in patients more than 15 kg body weight arrhythmias abolished. In the same patients the oral dosage was 12.2-22.6 mg/kg/d (mean 16.03 mg/kg/d) and 7.2-16.6 (mean 11.12 mg/kg/d). After 10 to 14 days a therapeutic serum level above 150 ng/ml could be maintained by a reduced oral dosage of 5.7-13.3 mg/kg/d) mean 8.5 mg/kg/d) and 3.6-11.1 mg/kg/d (mean 6.33 mg/kg/d) respectively. There were no side effects except for transitory by elevated gamma-GT in 8 patients. During a follow-up period of 1 month to 2.2 years (mean 1.6 years) 20 patients had no more arrhythmias, in 7 the number of arrhythmic attacks was reduced, and in 1 therapy failed.

Uric acid infarctions in the kidneys of newborn infants. A study on the changing incidence and on oxypurine ratios.

Among 1115 newborns who died during 1957--1976, 136 (12.2%) showed macroscopic renal uric acid infarctions. The incidence depended on the age of the infants and their fluid supply during the first days of life. After introduction of parenteral alkali-glucose infusion in the treatment of perinatal complications, the incidence of renal uric acid infarctions decreased from 19.3% to less than 1.0%. Analysis of the oxypurines in the renal uric acid infarctions of three newborns revealed high percentages of hypoxanthine (31.1%, 21.8% and 11.0%) along with the uric acid. Hypoxanthine ratios above 15% retrospectively point to chronic hypoxia of the newborn.