Robert Arnold

Transcatheter occlusion of the patent ductus arteriosus with Cook detachable coils.

OBJECTIVE: To report initial experience with a new occlusion device for native and residual patent ductus arteriosus. DESIGN: Descriptive study of consecutive non-randomised patients undergoing a new method of patent ductus arteriosus closure with detachable coils. SETTING: Tertiary centres for paediatric cardiology. PATIENTS: 71 consecutive patients, aged 1.2-22 years, with a patent ductus arteriosus (PDA) underwent elective transcatheter closure. 45 had native PDAs (group A) with a minimum diameter of 1.0 mm-5.0 mm (median 2.0 mm). A further 26 had undergone one or more previous occlusion attempts (group B). INTERVENTIONS: A total of 133 detachable (Cook) spring coils were successfully implanted in 70 patients. The procedure was performed transvenously in 51 patients, retrograde arterially in 13, and by both routes in a further 6 patients. One 5 mm coil migrated but was successfully retrieved. MAIN OUTCOME MEASURES: In group A colour flow Doppler echocardiography showed that complete occlusion was achieved in 40/45 (89%) at 24 hours, 41/45 (91%) at 1 month, and 44/45 (98%) by 6 months post procedure. Occlusion rates in residual PDAs were 22/25 (88%) occluded at 24 hours, 23/25 (92%) at 1 month, and 24/25 (96%) at 6 months follow up. CONCLUSIONS: Transcatheter occlusion using detachable (Cook) spring coils is a safe and effective alternative to presently available devices. The delivery system allows full retrieval of the coil until a satisfactory position is obtained.

Comparison of the sideris and Amplatzer septal occlusion devices

The results of transcatheter atrial septal defect (ASD) occlusion with 2 different devices (Sideris adjustable buttoned device vs Amplatzer Septal Occluder) were compared in 2 consecutive series of patients. Comparative outcomes were assessed by whether a device was implanted or not, by complications and fluoroscopy time of implantation, and by the incidence of residual shunting on transthoracic echocardiography at follow-up. The patient and defect characteristics were similar in both groups. Twenty-eight of 33 Sideris devices and 37 of 39 Amplatzer devices were implanted. The fluoroscopy time for the Amplatzer implants was 13.4 minutes (range 8 to 41) compared with 23.7 minutes (range 11 to 60.6) for the Sideris implants (p <0.001). The complete occlusion rate for the Amplatzer device was 93% compared with 44% for the Sideris device at 1 year (p <0.001). In conclusion, the Amplatzer device produces higher occlusion rates of ASDs with shorter fluoroscopy times.

Thrombolysis with tissue-type plasminogen activator following cardiac surgery in children

Three children with major intracardiac or vascular thrombosis following cardiac operations were treated with intravenous recombinant tissue-type plasminogen activator. The first patient, aged 10 yr, developed a left atrial thrombus following replacement of the mitral valve with a Björk-Shiley prosthesis. The second patient, aged 16 months, had a right atrial thrombus following a modified Fontan procedure for tricuspid atresia. Both were successfully treated with a short course of intravenous tissue plasminogen activator. The third patient, aged 19 months, developed the Budd-Chiari syndrome with occlusion of the inferior caval vein following a modified Fontan operation for double inlet left ventricle. Even though near-complete thrombolysis and recanalization of the inferior caval vein was achieved with three courses of tissue plasminogen activator on successive days, she died with failure of multiple organs. In all cases, the diagnosis was established by cross-sectional and Doppler echocardiography, and the response to therapy was monitored using the same technique. Thrombolytic therapy with systemic tissue-type plasminogen activator was safe and effective in the postoperative period, with no major haemorrhagic complications.

Aortico-left ventricular tunnel: Long-term outcome after surgical repair

Over a 14 year period, four children (three male, one female) underwent surgical correction of an aortico-left ventricular tunnel. All presented in infancy (age range 5 days to 9 months). The presenting feature was a systolic and diastolic murmur in all, one of whom developed heart failure within 2 weeks of presentation. In the first two patients, the echocardiographic findings were inconclusive and the diagnosis was confirmed at cardiac catheterization (at 10 and 23 months of age, respectively); the other two were diagnosed echocardiographically by two-dimensional and Doppler color flow imaging. All four patients underwent surgery by patch closure of the aortic end of the tunnel (three patients) or direct suture closure (one patient) and there were no deaths. The mean age at operation was 11 months. During a mean follow-up period of 71 months (range 2 to 157), three patients have clinical and echocardiographic evidence of trivial aortic valve regurgitation, which was noted in the immediate postoperative period in one and at early (less than 6 months) follow-up study in the other two. All are symptom-free, are taking no medications and are growing and developing normally. Aortico-left ventricular tunnel can be accurately diagnosed by echocardiography. In patients presenting in infancy, echocardiography also provides the necessary morphologic information to enable surgical correction without angiography. Early operation is associated with an excellent outcome, whereas repair at a later age is associated with a high incidence of residual aortic regurgitation requiring further surgery.

Captopril in treatment of infant heart failure: a preliminary report

We have studied retrospectively 18 infants who have received captopril for treatment of severe heart failure due to left-to-right shunts with pulmonary hypertension. Captopril has been administered in doses of up to 3.5 mg/kg/day (mean 2.47 mg/kg/day). Maintenance treatment with digoxin and frusemide was continued but potassium-sparing diuretics were stopped in most patients. The mean period of assessment was 19 days before and 27 days after commencing captopril. The mean daily weight gain before captopril was -7 g and after its introduction was + 13 g (P less than 0.001). There were statistically significant (P less than 0.05) falls in mean heart rate and respiratory rate and rises in plasma sodium concentration and feeding score. Plasma urea concentration fell but this did not reach statistical significance. Two patients suffered hypotension after increments in captopril dosage and subsequently had a rise in plasma urea and creatinine values. This adverse reaction may be linked to the presence of hyponatraemia. This preliminary report shows captopril may be useful in the control of severe heart failure in infancy.

Progressive Pulmonary Hypertension After the Arterial Switch Procedure

Abstract In conclusion, obstructive pulmonary vascular disease may be progressive despite early definitive repair in a subset of patients with transposition of the great arteries. Clinical awareness and the routine use of 2-dimensional Doppler echocardiography at follow-up evaluation should identify these patients early.

Paediatric cardiac assistance in developing and transitional countries: the impact of a fourteen year effort.

BACKGROUND Paediatric cardiac services are poorly developed or totally absent in underdeveloped countries. Institutions, foundations and interested individuals in those nations in which sophisticated paediatric cardiac surgery is practised have the ability to alleviate this problem by sponsoring paediatric cardio-surgical missions to provide care, and train local caregivers in developing, transitional, and third world countries. The ultimate benefit of such a programme is to improve the surgical abilities of the host institution. The purpose of this report is to present the impact of our programme over a period of 14 years. METHODS We specifically reviewed our database of patients from our missions, our team lists, surgical results, and the number and type of personnel trained in the institutions that we have assisted. In order for the institution to be entered into the study, the foundation had to provide at least 2 months of training. In addition, the institution had to respond to a simple questionnaire concerning the number and types of surgery performed at their facility before and after intervention by the foundation. RESULTS We made 140 trips to 27 institutions in 19 countries, with 12 of the visited institutions qualifying for inclusion. Of these, 9 institutions reported an increase in the number and complexity of cases currently being performed in their facility since the team intervened. This goal had not been accomplished in 3 institutions. The reasons for failure included the economic situation of the country, hospital and national politics, personality conflicts, and continued lack of hardware and disposables. CONCLUSIONS Paediatric cardiac service assistance can improve local services. A significant commitment is required by all parties involved.

Transcatheter occlusion of a post-Fontan residual hepatic vein to pulmonary venous atrium communication using the Amplatzer septal occluder

A residual hepatic vein to left atrial communication may result in progressive cyanosis after the Fontan procedure. This problem has usually been treated surgically by ligation or re-inclusion of the residual hepatic vein in the Fontan circulation. Previous attempts at transcatheter closure of such veins have been unsuccessful. An Amplatzer septal occluder was successfully used for transcatheter closure of a post-Fontan hepatic vein to pulmonary venous atrium fistula in an 8 year old boy.

Determinants of survival following repair of interrupted aortic arch in infancy

Between January 1971 and March 1987, surgery was performed in 26 infants with interrupted aortic arch. At operation the 14 boys and 12 girls weighted between 1.71 and 4.23 kg (mean +/- SD = 3.1 +/- 0.63 kg) and ranged in age from 2 to 90 days (13 +/- 18 days). The interruption was distal to the left subclavian artery in 4 (15%), between the left carotid and subclavian arteries in 20 (77%) and between the brachiocephalic (innominate) and left carotid arteries in 2 (8%). Associated complex cardiac lesions in 8 patients included complete transposition (2), common arterial trunk (2), aortopulmonary window (2), double inlet left ventricle (1) and tricuspid atresia (1). The remaining patients had an isolated ventricular septal defect. The arch was reconstructed with a prosthetic conduit in 14 patients; by a direct anastomosis in 6; using the subclavian artery in 3; and with the pulmonary trunk and the arterial duct in 2. Twenty patients (77%) underwent palliative surgery as the first stage of management, and banding of the pulmonary trunk was also performed in 16 of these. Five patients (19%) underwent primary complete repair of the interruption and intracardiac anomalies. One patient (4%) died soon after thoracotomy for palliative surgery. Of the 15 (57%, 70% confidence limits CL = 46-69%) early deaths, 7 occurred in patients with complex associated defects and 4 occurred when single stage repair was attempted. Survival following first-stage palliative surgery for arch interruption with isolated ventricular septal defect was 64% (9/14) [70% CL = 47-79%]. All of these patients subsequently underwent complete repair. Chi-squared and t-tests showed the year of operation and the type of operation (two-stage repair) to be associated with improved survival. It is concluded that a two-stage repair of interrupted aortic arch offers a reasonable alternative to primary complete correction and will lead to satisfactory subsequent repair in most cases.

Doppler echocardiographic evaluation of pulmonary artery flow after modified Fontan operation: importance of atrial contraction.

Doppler echocardiography was used to evaluate blood flow in the pulmonary artery in 14 patients 2 to 42 months (mean (SD) 17 (12) months) after a modified Fontan operation incorporating a direct atriopulmonary anastomosis. Preoperatively six patients had tricuspid atresia, six had a double inlet left ventricle, and two had pulmonary atresia with an intact ventricular septum. The postoperative rhythm was sinus in 11 patients, junctional in one, ventricular pacing in one, and atrioventricular sequential pacing in one. In one patient the Doppler trace was unsatisfactory for analysis. In all patients forward flow in the pulmonary artery had biphasic peaks related to both atrial and ventricular contraction. The mean (SD) peak flow velocity that was synchronous with atrial contraction was 80 (30) cm/s and that synchronous with ventricular contraction was 74 (23) cm/s. The atrial contribution to total pulmonary artery flow, assessed by velocity-time integrals, varied between 22% and 73% (mean (SD) 45 (14)%). In patients with tricuspid atresia the mean (SD) peak flow velocity with atrial contraction was 90 (27) cm/s and that with ventricular contraction was mean (SD) 68 (24) cm/s. In patients with double inlet left ventricle the mean (SD) peak flow velocity was 67 (36) cm/s with atrial contraction and 80 (25) cm/s with ventricular contraction. The atrial contribution to total pulmonary blood flow in patients with tricuspid atresia was significantly higher (53 (11)%) than in those with double inlet left ventricle (37 (14)%). Pulmonary artery flow after modified Fontan operation was biphasic and was related to both atrial and ventricular contraction. The atrial contribution to pulmonary blood flow is greater in patients with tricuspid atresia than in those with a double inlet left ventricle. The mechanism of the second peak related to ventricular contraction is unknown.