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To investigate the possible causes of left ventricular dysfunction after total correction of tetralogy of Fallot, 84 patients, aged 1 1/2 to 16 years, were studied by left ventricular cineangiography both before and a mean of 4.6 months after operation. Left ventricular ejection fraction and mean velocity of circumferential fibre shortening were calculated; using multivariate analysis the results were correlated with age at operation, the degree of hypoxia and polycythaemia before operation, occurrence of hypoxic spells, and the duration of operative procedures (cardiopulmonary bypass and aortic cross clamping). The postoperative left ventricular ejection fraction was decreased slightly or moderately in 46% of patients. The variable most significantly associated with altered left ventricular function was a history of hypoxic spells. Age, the degree of chronic hypoxia, and polycythaemia did not correlate significantly with left ventricular function indices. Although no correlation was found between the duration of cardiopulmonary bypass and left ventricular ejection fraction, bypass times exceeding 120 minutes were associated with decreased ejection fractions; this was statistically significant and independent of the variable "hypoxic spells". Thus repeated episodes of acute hypoxia and long operative procedures appear to have a deleterious effect on left ventricular function in tetralogy of Fallot. [ABSTRACT FROM PUBLISHER]

To evaluate the usefulness and accuracy of calculating left ventricular volume and ejection fraction from cross sectional echocardiograms in patients with tetralogy of Fallot, 28 patients were studied within 24 hours of cineangiography. Indexed end diastolic and end systolic volumes were calculated from three different paired echocardiographic projections: (a) the two and four chamber views from the apical impulse window, (b) the parasternal long axis view and the subxiphoid long axis view, and (c) the four chamber view and short axis precordial views at mitral and papillary muscle level. Volumes were calculated in five different ways using three different algorithms (area length, Simpson's rule, the Parisi formula). The results were compared with data obtained from biplane angiograms using Graham's formula. The correlation varied with the algorithm used: the best results were obtained with the area length method using the parasternal long axis view and the sub-xiphoid view. The correlation was less accurate for the ejection fraction. The second best correlation was obtained with the area length method using the two and four chamber apical views; the other correlations were less satisfactory. Thus these results show that left ventricular volumes can be accurately assessed by cross sectional echocardiography in children with tetralogy of Fallot and that the ejection fraction can be satisfactorily estimated. The results depend on careful gain setting and precise demonstration of the left ventricular endocardium, which is best seen in the sub-xiphoid and long axis views. [ABSTRACT FROM PUBLISHER]

Haemodynamic variables and left ventricular function were studied before and after mitral valve replacement in 44 children age 3 to 17 years (mean 11.9 years). Thirty-nine Starr-Edwards prostheses and five Hancock prostheses were used; postoperative study took place two to six months (mean 3.9 months) after operation. Pulmonary hypertension was present preoperatively in most patients, with mean pulmonary artery pressures of 18 to 75 (mean 46.5 mmHg). Postoperatively there was a pronounced drop in pressure to a mean value of 25.6 mmHg, partially explained by a decrease in pulmonary capillary wedge pressure. Pulmonary arteriolar resistance, however, also decreased conspicuously from an average of 590 dynes s cm-5 m-2 preoperatively to 282 dynes s cm-5 m-2 postoperatively. A return to normal resistance was seen in every case when preoperative resistance did not exceed 650 dynes s cm-5 m-2; above this threshold some degree of pulmonary hypertension often persisted. The residual gradient across the prosthetic valve was slightly higher for the Hancock than for the Starr-Edwards prosthesis (mean 8.7 mmHg, vs mean 6.9 mmHg). The left ventricular end-diastolic volume was much increased before surgery, with a mean value of 190 ml/m2; it decreased conspicuously after operation to 103 ml/m2. The left ventricular ejection fraction ranged from 40% to 76% (mean 57%) before operation; there was no significant change after operation, with values ranging from 40% to 73%. This left ventricular dysfunction is probably the result of myocardial injury caused by a chronic volume overload and the sequelae of rheumatic carditis. [ABSTRACT FROM PUBLISHER]

Plasma renin activity and one-dimensional echocardiographic measurements of the left atrium and left ventricle as well as function indices were studied repeatedly in 20 children with various cardiopathies (ages: 9 months to 15 years) before and after corrective surgery. Nine children had tetralogy of Fallot, four had pulmonary stenosis, four had rheumatic heart disease, two had ventricular septal defect, and one had atrial septal defect. Plasma renin activity was normal preoperatively, but increased significantly immediately after surgery, was still significantly higher on the 12th postoperative day and returned to normal six to eight weeks after surgery. Patients with tetralogy of Fallot and pulmonary stenosis had higher plasma renin activity values than the others. There was a positive correlation between plasma renin activity and postoperative percentage change of the left ventricular dimension. In patients with tetralogy of Fallot and pulmonary stenosis, this meant that plasma renin activity became normal when the preoperatively small left ventricle reached its normal dimension. This adjustment occurred slowly over a period of two months. In rheumatic heart disease and left-to-right shunt lesions, plasma renin activities became normal when the preoperatively dilated left ventricle decreased in size towards normal values; the plasma renin activities of these patients had reached normal levels by the fifth postoperative day. The renin secretion is modulated by various factors: of these, ventricular size and pulmonary venous return seem to be of importance. [ABSTRACT FROM PUBLISHER]

Right and left ventricular dimensions and function were determined by one-dimensional echocardiography in patients with tetralogy of Fallot before and after corrective surgery. Thirty-five children (mean age: 5.9 years) were examined; 5 of them died immediately after operation; 5 had palliative operations only. The remaining 25 had repeat echocardiography 2 to 4 and/or 8 weeks after total correction. Compared with normal values, preoperative left ventricular dimensions were smaller than expected for body surface area (mean = 85.4% +/- 1.9 SEM, range 65 to 105% of normal); 21 values were below the 5th centile. Postoperatively, left ventricular dimensions increased significantly and reached normal values in most cases (mean = 103.2 +/- 2.0% SEM, range 81 to 121%). The main increase took place in the first 4 weeks (P less than 0.001; mean difference 0.7 +/- 0.14 cm). The 5 children who died after operation had smaller left ventricular dimensions than the survivors (P less than 0.01). Left ventricular function was evaluated by measuring mean circumferential fibre shortening, per cent shortening, and ejection fraction; they were normal in most patients and diminished only insignificantly after corrective surgery. Right ventricular dimensions were increased preoperatively but decreased significantly (P less than 0.001) postoperatively. Septal movement was normal in direction and excessive in displacement in most patients before operation; immediately after operation it became flat or showed paradoxical motion. Two months after operation 50 per cent of the children showed a return to normal septal movement. Early appearance of normal septal movement could be related to the presence of significant pulmonary stenosis. It is concluded that a high percentage of patients with tetralogy of Fallot have underdeveloped but normally functioning left ventricles which adapt well to the new postoperative state. [ABSTRACT FROM PUBLISHER]

OBJECTIVE--To assess the effect of inhaled nitric oxide (NO) on severe postoperative pulmonary hypertension in children after surgical repair of a congenital heart defect. DESIGN--A pilot study of NO administration to 7 consecutive children who required adrenergic support and in whom postoperative mean pulmonary artery pressure was more than two thirds of mean systemic pressure and persisted despite alkalotic hyperventilation. SETTING--Routine care after cardiac surgery for congenital heart disease in a multidisciplinary paediatric intensive care unit. METHODS--Continuous inhalation of NO, initially at 15 ppm. Therefore, daily attempts at complete weaning or at reducing NO to the lowest effective dose. RESULTS--In 6 of the 7 children NO inhalation selectively decreased mean (SD) pulmonary artery pressure from 51 (12) to 31 (9) mm Hg (P < 0.05) while mean systemic arterial pressure was unchanged (68 (10) v 71 (7) mm Hg) (NS) and the arteriovenous difference in oxygen content decreased from 6.7 (0.9) to 4.8 (0.8) vol% (P < 0.05). Concomitantly PaO2 increased from 158 (98) to 231 (79) mm Hg) (P < 0.05). The seventh child showed no response to NO up to 80 ppm, could not be weaned from cardiopulmonary bypass, and died in the operating room. In responders, attempts at early weaning from NO inhalation always failed and NO at concentrations of less than 10 ppm was continuously administered for a median of 9.5 days (range 4 to 16 days) until complete weaning was possible from a mean dose of 3.9 (2.9) ppm. Methaemoglobinaemia remained below 2% and nitrogen dioxide concentrations usually ranged from 0.1 to 0.2 ppm. One child later died and five were discharged. A few months after surgery Doppler echocardiography (and catheterisation in one) showed evidence of regression of pulmonary hypertension in all 5. CONCLUSIONS--Inhalation of NO reduced pulmonary artery pressure in children with severe pulmonary hypertension after cardiac surgery and this effect was maintained over several days at concentrations carrying little risk of toxicity. [ABSTRACT FROM PUBLISHER]

OBJECTIVE--To determine the prognostic significance of ventricular late potentials and spontaneous ventricular arrhythmias detected early after surgical repair of tetralogy of Fallot. DESIGN--Prospective observational. SETTING--Cardiology department of a teaching hospital. METHODS--Between June 1984 and June 1991, 104 children (63 boys, 41 girls) were studied by signal averaging and 24 hour ambulatory monitoring after surgical repair of tetralogy of Fallot. Mean (SD) age at operation was 6 (3) years, mean interval between operation and evaluation was 8 (25) months, and the follow up after evaluation was one to 88 (mean 30) months. RESULTS--Ventricular late potentials were detected in 24/104 patients (23%) and spontaneous ventricular arrhythmias in 39/96 patients (38%); usually (in 81%) these were unifocal and rare. Patients with ventricular late potentials were older at operation than patients without late potentials (9 (3) v 6 (3) years, P = 0.002). No correlation was found between the presence of ventricular late potentials and the presence or complexity of spontaneous ventricular arrhythmias early after operation. During the mean follow up of 2.5 years no case of sudden death or sustained ventricular tachycardia was found. CONCLUSION--Short-term prognosis after surgical repair of tetralogy of Fallot is good; ventricular late potentials and spontaneous ventricular arrhythmias are often detected shortly after operation, but in the medium term follow up they do not predict sudden death or serious ventricular arrhythmias. [ABSTRACT FROM PUBLISHER]

When propranolol is given to prevent hypoxaemic episodes in children with tetralogy of Fallot who are awaiting operation it is advisable to continue the treatment until shortly before the induction of anaesthesia. Because catecholamines are often required to maintain adequate cardiac output after surgical correction the effect of preoperative treatment with beta blockers on the response to isoprenaline after the operation was investigated in nine children given propranolol before operation and nine who were not. They were studied three and 24 hours after cardiopulmonary bypass. The haemodynamic response to increasing doses of infused isoprenaline was monitored. Immediately after cardiopulmonary bypass the response to isoprenaline was significantly blunted in the patients who had been given propranolol before operation. Their dose-response curve lay to the right of that for patients not given propranolol, and this indicates competitive inhibition. Propranolol concentrations in the blood and myocardium correlated significantly with the heart rate response to isoprenaline. Twenty four hours after operation the isoprenaline response was similar in both groups and concentrations of propranolol in the blood were minimal or undetectable. beta Blockers given up to the time of operation significantly altered the postoperative response to catecholamines. [ABSTRACT FROM PUBLISHER]

Double venous stenting of the superior vena cava and inferior vena cava was successfully performed after failed balloon angioplasty in a young woman who had venoatrial narrowing and kinking after repeated Mustard procedure for D-transposition of great vessels. Self-expanding metallic stents were used. Angiography showed that the first stent was fully patient after six months when a second stent was implanted. This operation was followed by sustained clinical improvement. The present report shows the feasibility and success of stenting of the great veins when postoperative narrowing or kinking is unresponsive to balloon angioplasty alone. [ABSTRACT FROM PUBLISHER]

A new balloon for valvuloplasty (Trefoil balloon) was successfully used in a 12 year old boy with congenital aortic stenosis. The Trefoil balloon consists of three angioplasty balloons mounted in parallel on a single shaft. When they are inflated simultaneously they produce a rosette that allows blood flow to continue through the valve. The aortic pressure only dropped to 75 mm Hg during a 15 s balloon dilatation at 4 bar (400 kPa). The procedure reduced the transvalvar gradient from 45 to 15 mm Hg. [ABSTRACT FROM PUBLISHER]

Background: Complete correction of tetralogy of Fallot has good long-term results. Right ventricular outflow tract obstruction and pulmonary insufficiency occur which require reintervention. The present study evaluated the efficacy of reoperation following complete correction of tetralogy of Fallot, the sites of recurrences and impact of techniques used at first operation., Methods: Between 1980 and 1999, 501 patients underwent complete correction of tetralogy of Fallot. Reoperation rate was 7.4%. Residual or recurrent right ventricular outflow tract stenosis was seen in 25 patients (68%), and 7 patients (19%) had severe pulmonary insufficiency. Age at redo was 9.1+/-6.4 years. Restenosis was most frequently observed (75%) at the bifurcation of the pulmonary artery. Extended 1-patch enlargement was used until 1989 and thereafter changed to a 2-patch technique., Results: Valvar-supravalvar 1-patch technique had a redo rate of 33.3%, compared with 4.3% for the 2-patch technique, p = 0.0264, with excellent freedom from reoperation rate. At reoperation right ventricular-pulmonary artery (RV-PA) conduits managed 29 patients and 3 had supravalvar patch enlargement. Hospital mortality was 5.4% (2 of 37). Twenty-five patients (68%) were in New York Heart Association functional class I to II at end of the follow-up, and none required further interventions., Conclusions: Redo rate following complete correction of tetralogy of Fallot was 7.4%. Right ventricular outflow tract pathology was the dominant reason for reoperations (86%). At reoperation, RV-PA conduits was the most frequently used technique. Reoperation was efficient in reducing the RV-PA gradient, had low hospital and late mortality. A 2-patch valvar-supravalvar enlargement at first operation reduced the risk for redo in long-term follow-up.

Objectives: Our goal was to evaluate the midterm results of aortic valve repair by a more sophisticated tailoring of cusp extension-taking into account the dimensions of the native aortic cusps-with the use of fresh autologous pericardium., Patients and Methods: Forty-one children who had severe rheumatic aortic insufficiency (mean age 11.5 +/- 2.7 years) underwent aortic valve repair by means of this cusp extension technique over a 5-year period. Twenty-four of them underwent concomitant mitral valve repair for associated rheumatic mitral valve disease. All children were then followed up by transthoracic echocardiography before discharge, at 3 and 6 months after the operation, and at yearly intervals thereafter., Results: Follow-up was complete in all patients and ranged from 3 months to 5 years (median 3 years). No operative and no early postoperative deaths occurred. Only 1 patient died, 9 months after the operation, of septicemia and multiple organ failure. Actuarial survival was 97% at 1 year and has remained unchanged at 3 years. On discharge, the degree of aortic insufficiency was grade 0 for 27 children and grade I for 14. Exacerbation of aortic insufficiency from grade I to grade II was observed in only 1 patient, and none of the children required reoperation for aortic insufficiency during the follow-up period. Mean peak systolic aortic valve gradients at discharge were lower than preoperative values (P =.04), and no significant increase in the peak systolic transvalvular gradient was detected thereafter during the follow-up period. Mean left ventricular dimensions were significantly reduced at discharge when compared with preoperative values (P <.0001)., Conclusions: Functional results of aortic valve repair with cusp extension using fresh pericardium have been satisfactory at medium term, particularly in children with a small aortic anulus at the time of initial repair, because the expansion potential of fresh autologous pericardium is equivalent to that of the growing sinotubular junction and aortic anulus diameters.

A rare case of congenital mitral insufficiency characterized by six well-demarcated leaflets of mitral valve and annular dilatation is reported. At operation, the mitral valve was successfully repaired by resection of the posterior median leaflet with subsequent annular plication, closure of unusual valvular tissue divisions, and ring annuloplasty.

The purpose of this study was to measure changes in serum atrial natriuretic factor concentrations immediately after heart operations in children under baseline conditions and in response to continuous infusion of dopamine (2.5 and 5.0 micrograms/kg/min). During control periods, levels of atrial natriuretic factor were elevated at 190 +/- 24 and 199 +/- 36 pg/ml. The cardiac index was 2.6 L/min/m2 and the renal plasma flow was decreased to 269 +/- 41 ml/min/1.73 m2, indicating a state of renal vasoconstriction (mean renal fraction of cardiac index of 10.0% +/- 1.0%). The mean sodium fractional reabsorption was 99.0% +/- 0.2%. During dopamine infusion, atrial natriuretic factor concentrations increased to 259 +/- 57 pg/ml and to 280 +/- 56 pg/ml, with dopamine 2.5 and 5.0 micrograms/kg/min, respectively (p = not significant), whereas left atrial pressure decreased from 11.7 +/- 0.9 mm Hg during the control period to 10.1 +/- 0.9 and to 9.9 +/- 1.0 mm Hg (p less than 0.05). No correlation was found between changes in left atrial pressure and atrial natriuretic factor levels. Dopamine at 5 micrograms/kg/min increased the cardiac index to 3.0 +/- 0.2 L/min/m2 (p less than 0.001) and the renal plasma flow to 406 +/- 61 ml/min 1.73 m2 (p less than 0.001), alleviating the renal vasoconstriction. The mean urinary sodium excretion increased to 0.33 +/- 0.08 mmol/kg/hr (p less than 0.01). The atrial natriuretic factor plasma concentrations were not related to the urinary sodium excretion, renal plasma flow, or glomerular filtration rate during the control period or during dopamine treatment. These data indicate that after heart operations in children, low urinary sodium excretion occurs despite high circulating atrial natriuretic factor levels. Atrial natriuretic factor concentrations were related neither to left atrial pressures nor to the renal changes induced by dopamine.

To investigate the alpha-atrial natriuretic factor in congenital cardiac malformations, three groups of children, aged 7 months to 16 years, with different hemodynamic situations were studied during routine cardiac catheterization. Twenty-one (group I) had tetralogy of Fallot, 24 (group II) had a left to right shunt with pulmonary hypertension and 12 (control group) had a minor cardiac lesion. Alpha-atrial natriuretic factor levels were determined by a radioimmunoassay on blood samples from the inferior vena cava, right atrium, pulmonary artery, left atrium and aorta. To evaluate the effect of an acute volume load, measurements of hormone and pressures were repeated after right ventriculography. Alpha-atrial natriuretic factor levels varied over a wide range in all groups and in all chambers investigated. Nevertheless, children with pulmonary hypertension had significantly higher levels of the hormone (p less than 0.01) and were well separated from the control group, but less well from those with tetralogy of Fallot. A 50% increase of alpha-atrial natriuretic factor from the inferior vena cava to the right atrium occurred in patients with shunt lesions with pulmonary hypertension and in patients with tetralogy of Fallot (p less than 0.001) and a further 30% increase from the right atrium to the pulmonary artery (p less than 0.05). After right ventriculography, a 100% to 200% increase of alpha-atrial natriuretic factor was observed in the total sample (p less than 0.001). A positive correlation was observed between right atrial mean pressure and right atrial alpha-atrial natriuretic factor (r = 0.63) and between pulmonary artery mean pressure and pulmonary artery alpha-atrial natriuretic factor (r = 0.61).(ABSTRACT TRUNCATED AT 250 WORDS)

Late complete heart block may occur after correction of tetralogy of Fallot. Whether postoperative electrophysiologic studies can identify patients at risk of developing this conduction disturbance is unknown. In this study, 57 children who underwent electrophysiologic investigation after correction of tetralogy of Fallot were followed up for 1 to 13 (mean 6.5) years after the investigation. One late death and two cases of late complete heart block occurred. The late death was due to ventricular arrhythmia and not to a conduction disturbance. The cases of late heart block occurred 2 and 5 years, respectively, after electrophysiologic study, and in both cases the patient had a prolonged HV interval; in one patient progressive lengthening of the HV interval could be demonstrated at two subsequent studies 1 year apart. Another five patients with a prolonged HV interval had normally conducted sinus rhythm up to 11 years after study. Atrial pacing at increasing rates (up to the occurrence of second degree atrioventricular block) during electrophysiologic study was the best means of predicting late heart block: of three patients with block below the bundle of His occurring at pacing rates less than 180/min, two developed late complete heart block. Thus, electrophysiologic testing of the conduction system after correction of tetralogy of Fallot is useful in predicting late complete heart block and should be performed in patients with a history of transient heart block after surgery and in those with a prolonged PR interval.

Increased pulmonary blood flow was produced in 1-month-old piglets by means of left pneumonectomy, arteriovenous fistulas in the neck, and a combination of both. Physiologic and histologic studies of the pulmonary vascular bed were done 1-9 months after operation. A progressive, moderate increase in pulmonary artery (PA) pressure was observed, especially between 1 and 6 months after surgery. This was flow related, i.e., the group with the highest flow (pneumonectomy plus fistula) was found to have the most prominent increase in pressure. Mean Pa pressure at 6 months was 28.7 +/- 0.07 mm Hg in this group, vs 24.4 +/- 0.48 mm Hg in the group with pneumonectomy alone and 17.2 +/- 0.48 mm Hg in controls (P less than 0.01). The pressure response to hypoxia in pigs with high pulmonary blood flow was not different from that found in control animals. Histologic studies revealed that small arteries and arterioles of pigs with high pulmonary blood flow had a decreased relative wall thickness because of dilation up to 6 months follow-up. This was flow related, the group with the highest flow having the lowest wall thickness to vessel diameter ratio; relative wall thickness (in percentage of the vessel diameter ) at 6 months was 6.1 +/- 0.44% in pigs with with pneumonectomy plus fistula, vs 9.6 +/- 0.40% in the group with pneumonectomy alone and 11.2 +/- 0.61% in controls (P less than 0.01). In the group with the highest flow, thick walled arterioles appeared at 9 months follow-up, scattered among dilated ones; between 6 and 9 months after operation, ranging from 6.1 +/- 0.44% to 11.3 +/- 0.73% (P less than 0.01). In five animals with high flow, the right PA (main branch) showed patchy intimal thickening, small cystic spaces filled with mucopolysaccharides in the media, and muscular hypertrophy.