European Heart Journal Advance Access originally published online on October 16, 2006
European Heart Journal 2007 28(6):698; doi:10.1093/eurheartj/ehl323
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
‘Cobra malformation’ of an Amplatzer device during percutaneous closure of a ventricular septal defect
Department of Cardiology, John Radcliffe Hospital, Oxford, OX3 9DU, UK
* Corresponding author. Tel: +44 1865 220648; fax +44 1865 221194. E-mail address: rschrale{at}hotmail.com
A 76-year-old man presented with successfully resuscitated cardiac arrest due to ventricular tachycardia. He was in florid pulmonary oedema, but maintaining a blood pressure and electrically stable. Past medical history included hypertension and a permanent pacemaker for syncope.
Transthoracic echocardiography revealed a muscular ventricular septum rupture with gross left-to-right shunting (Panel A). Clinical progress was marked by refractory pulmonary oedema and recurrent gastrointestinal bleeding. Due to excessive surgical risk he underwent percutaneous closure of his ventricular septal defect (VSD) with intracardiac echocardiography and local anaesthesia. Amplatzer muscular VSD occluders of 14 and 24 mm (AGA Medical, Golden Valley, USA) failed to secure across the defect (Panel B). A 28 mm Amplatzer ASD occluder device (AGA Medical) succumbed to a ‘cobra malformation’, but was securely in situ and therefore accepted as the final result (Panel C). Imaging documented reduced interventricular shunting and mean arterial pressure rose 14 mmHg to 80 mmHg. Day 1 echocardiography demonstrated delayed device reformation (Panel D). Pulmonary oedema improved significantly, but on day 2 he suffered a fatal gastrointestinal haemorrhage. Limited autopsy examination revealed a well-deployed device within an elliptical 22 mm infarct-related VSD.
‘Cobra malformation’ describes the characteristic angiographic appearance of the Amplatzer device deployed in a distorted fashion. Causes include device twisting, manufacturing fault, or tethering on intracardiac structures. Generally, the device should be retrieved and may deploy normally on repositioning. In our patient, the malformation was accepted as the final result due to secure a position, prolonged procedure time in an unwell patient, and favourable left-to-right pressure differential. As illustrated, late reformation may occur.
Panel A. High muscular VSD (white arrow) seen on transthoracic echocardiography.
Panel B. Ventriculography documents the large septal defect (white arrow) with left-to-right shunting. The 24 mm Amplatzer muscular VSD occluder (AGA Medical) failed to secure across the defect and is visible in the right ventricle, attached to the delivery cable (asterisk). The intracardiac echocardiography catheter is visible parallel to the cable.
Panel C. ‘Cobra malformation’ in the 28 mm Amplatzer ASD occluder device (AGA Medical).
Panel D. Subsequent echocardiography demonstrated delayed device reformation with the usual two-disc shape visible across the ventricular septum (white arrow).
CiteULike 
Connotea 
Del.icio.us What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||