Neil Wilson

Transcatheter closure of atrial septal defect and interatrial communications with a new self expanding nitinol double disc device (Amplatzer septal occluder): multicentre UK experience

OBJECTIVE To review the safety and efficacy of the Amplatzer septal occluder for transcatheter closure of interatrial communications (atrial septal defects (ASD), fenestrated Fontan (FF), patent foramen ovale (PFO)). DESIGN Prospective study following a common protocol for patient selection and technique of deployment in all participating centres. SETTING Multicentre study representing total United Kingdom experience. PATIENTS First 100 consecutive patients in whom an Amplatzer septal occluder was used to close a clinically significant ASD or interatrial communication. INTERVENTIONS All procedures performed under general anaesthesia with transoesophageal echocardiographic guidance. Interatrial communications were assessed by transoesophageal echocardiography with reference to size, position in the interatrial septum, proximity to surrounding structures, and adequacy of septal rim. Stretched diameter of the interatrial communications was determined by balloon sizing. Device selection was based on and matched to the stretched diameter of the communication. MAIN OUTCOME MEASURES Success defined as deployment of device in a stable position to occlude the interatrial communication without inducing functional abnormality or anatomical obstruction. Occlusion status determined by transoesophageal echocardiography during procedure and by transthoracic echocardiography on follow up. Clinical status and occlusion rates assessed at 24 hours, one month, and three months. RESULTS 101 procedures were performed in 100 patients (86 ASD, 7 FF, 7 PFO), age 1.7 to 64.3 years (mean (SD), 13.3 (13.9)), weight 9.2 to 100.0 kg (mean 32.5 (23.5)). Procedure time ranged from 30 to 180 minutes (mean 92.4 (29.0)) and fluoroscopy time from 6.0 to 49.0 minutes (mean 16.1 (8.0)). There were seven failures, all occurring in patients with ASD, and one embolisation requiring surgical removal. Immediate total occlusion rate was 20.4%, rising to 84.9% after 24 hours. Total occlusion rates at the one and three month follow up were 92.5% and 98.9%, respectively. Complications were: transient ST elevation (1), transient atrioventricular block (1), presumed deep vein thrombosis (1), presumed transient ischaemic attack (1). CONCLUSIONS It appears feasible to close interatrial communications and atrial septal defects up to 26 mm stretched diameter safely with the Amplatzer septal occluder. Short term results confirm an early high occlusion rate with no major complications. Careful selection of cases based on the echocardiographic morphology of the ASD and accurate assessment of their stretched diameter is of utmost importance. Further experience with the larger devices and longer term results are required before a firm conclusion regarding its use can be made.

Total UK multi-centre experience with a novel arterial occlusion device (Duct Occlud pfm).

OBJECTIVE: To report the total UK multicentre experience of a novel arterial occlusion device (Duct Occlud pfm). DESIGN: Descriptive study of selected non-randomised paediatric patients with a variety of aortopulmonary connections. SETTING: Five UK tertiary referral centres for congenital heart disease. PATIENTS AND METHODS: Between March 1994 and February 1995, 57 children aged 2 weeks to 14 years (median 50 months) underwent attempted closure of their aortopulmonary connection. Fifty one had persistent arterial ducts and 9 of them had had a Rashkind umbrella device implanted. Five patients had superfluous modified Blalock-Taussig shunts (mBTS). In one there was also a native major aortopulmonary collateral artery (MAPCA). Another patient had a native major aortopulmonary connection (APC). Transcatheter occlusion was attempted in all cases through a 4 F delivery catheter. RESULTS: Devices were successfully deployed in 49/57 (86%) patients. Seven of 51 cases with persistent arterial ducts were judged too large for the device and a Rashkind umbrella was used. 40 (91%) of the 44 in whom the detachable coil device was used had complete occlusion at 24 hours on colour flow Doppler echocardiography. Devices were successfully deployed in all 6 remaining patients (4 mBTS, 1 mBTS + MAPCA, and 1 APC). Embolisation of a device occurred on 4 occasions. Two devices were not retrieved but caused no apparent clinical problems. CONCLUSION: This novel detachable coil type occlusion system compares favourably with other methods of transcatheter occlusion of native, residual, or surgically created aortopulmonary shunts. The delivery system allows its use in small children.

Assessment of the quality of neonatal echocardiographic images transmitted by ISDN telephone lines

OBJECTIVE To assess the quality of echocardiographic images from neonates transmitted over Integrated Service Digital Network 2 (ISDN2) channels. DESIGN Echocardiographic images were viewed live in real time either by a direct video link or by transmission over the commercial network, using one, two, or three ISDN2 channels. The order of the viewing formats was random and four observers marked each view for potential for provision of complete diagnostic information and quality. SETTING Cardiology department of tertiary referral centre for paediatric cardiac services. ISDN lines were positioned in two nearby rooms. Telephone connection was through the commercial network and video connection by a direct video cable. PATIENTS 10 neonates were studied (weight 2600 to 3900 g). In each, nine echocardiographic studies were undertaken to assess imaging (M mode and cross sectional) and Doppler (spectral and colour) quality. RESULTS No significant differences were found in diagnostic ability between the different formats for M mode, colour, or spectral Doppler studies. For cross sectional imaging the diagnostic information and image quality increased with increasing numbers of ISDN channels. With six channels there was little difference from the directly connected images. CONCLUSIONS In echocardiographic assessment of the newborn, one or two ISDN2 channels will transmit images of satisfactory quality in many situations but three or more channels are necessary to ensure minimum degradation of the live image.

Transhepatic approach for cardiac catheterisation in children: initial experience

AIM To assess initial experience of cardiac catheterisation in children by the transhepatic approach where conventional venous access is impossible. PATIENTS AND METHODS Percutaneous transhepatic cardiac catheterisation was performed on six occasions in five children (three male) aged 4 to 36 months (mean 17 months). All children had documented femoral venous occlusion and all but one had occlusion of the superior vena cava. Ultrasound was used in five of the six procedures to help identify a large hepatic vein. A 4 F or 5 F sheath was introduced into the vein using the Seldinger technique. In the fourth patient, hepatic venous access was obtained immediately without the assistance of ultrasound. RESULTS Percutaneous transhepatic catheterisation was successfully performed at all six attempts. Total procedure time ranged from 120 to 200 minutes (mean 138 minutes) and screening time from 14 to 22 minutes (mean 16.8 minutes). A serious complication was encountered in only one patient who had a retroperitoneal bleed after administration of thrombolysis for loss of femoral arterial pulse. CONCLUSIONS The percutaneous transhepatic technique can provide a safe alternative approach for cardiac catheterisation in children with multiple venous occlusion. The procedure can be performed very simply using the Seldinger technique and equipment normally used for conventional venous cannulation for cardiac catheterisation.

Preprocedural Risk Assessment Prior to PPVI with CMR and Cardiac CT

Percutaneous pulmonary valve intervention (PPVI) is a less invasive and less costly approach to pulmonary valve replacement compared with the surgical alternative. Potential complications of PPVI include coronary compression and pulmonary arterial injury/rupture. The purpose of this study was to characterize the morphological risk factors for PPVI complication with cardiac MRI and cardiac CTA. A retrospective review of 88 PPVI procedures was performed. 44 patients had preprocedural cardiac MRIs or CTAs available for review. Multiple morphological variables on cardiac MRI and CTA were compared with known PPVI outcome and used to investigate associations of variables in determining coronary compression or right ventricular–pulmonary arterial conduit injury. The most significant risk factor for coronary artery compression was the proximity of the coronary arteries to the conduit. In all patients with coronary compression during PPVI, the coronary artery touched the conduit on the preprocedural CTA/MRI, whilst in patients without coronary compression the mean distance between the coronary artery and the conduit was 4.9xa0mm (range of 0.8–20xa0mm). Multivariable regression analysis demonstrated that exuberant conduit calcification was the most important variable for determining conduit injury. Position of the coronary artery directly contacting the conduit without any intervening fat may predict coronary artery compression during PPVI. Exuberant conduit calcification increases the risk of PPVI-associated conduit injury. Close attention to these factors is recommended prior to intervention in patients with pulmonary valve dysfunction.

Outcome after transcatheter occlusion of patent ductus arteriosus in infants less than 6 kg: A national study from United Kingdom and Ireland

This study aimed to report our national experience with transcatheter patent ductus arteriosus (PDA) occlusion in infants weighing <6 kg.

Philosopher, Pediatrician, Pathologist? John Locke’s Thoughts on Rhicketts and a Missed Case of Ebstein’s Anomaly

John Locke (1632–1704) is primarily remembered for his highly influential philosophical works regarded as the engine of the Enlightenment. It is less well known that Locke also was a highly regarded and influential physician. In 1666, Locke performed a postmortem examination of an 18-month-old child who had physical signs of rickets. Locke, a medical student at this time, attributed rickets as the cause of death. However, Locke described and recognized severe cardiac abnormality and speculated that right-to-left interatrial shunting was part of rickets. Locke’s clearly described clinical history and postmortem findings are more consistent with a congenital cardiac malformation, an Ebstein’s anomaly, in addition to the rickets. Locke did not consider this case as other than rickets. His opinion was not challenged when the case report was re-presented in the past half century. This article forces a reevaluation of the 17th-century understanding of infant cardiovascular physiology and pathology: Locke clearly gives one of the earliest descriptions of right-to-left shunting through the patent foramen ovale. It is unfortunate that Locke apparently did not discuss his postmortem findings with his contemporary Richard Lower (1631–1691), whose celebrated masterpiece on the heart, Tractatus de Corde, was published in 1669.

Measuring Flow Hemodynamic Indices and Oxygen Consumption in Children with Pulmonary Hypertension: A Comparison of Catheterization and Phase-Contrast MRI

We sought to compare pulmonary flow hemodynamic indices obtained by Fick and thermodilution catheterization techniques with phase-contrast MRI (PC-MRI) in children with diverse etiologies of pulmonary arterial hypertension (PAH). Calculation of pulmonary flow (

SAPIEN valve for percutaneous transcatheter pulmonary valve replacement without “pre-stenting”: A multi-institutional experience

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