Compression, distortion and dislodgement of large caliber stents in congenital heart defects caused by cardiopulmonary resuscitation: a case series and review of the literature.

Stenting of vascular, extracardiac or lately intracardiac stenosis has become an established interventional treatment for a variety of problems in congenital or acquired heart disease. Most stent procedures are completed successfully and the long-term outcome is favorable in the majority of cases. Stent collapse or deformation is a well recognized entity in peripheral stents and can be attributed to insufficient radial force; it can also be attributed to excessive external forces, like deformation of stents in the right ventricular outflow tract, where external compression is combined with continuous movement caused by the beating heart. The protection of the thoracic cage may prove to be insufficient in extraordinary circumstances, such as chest compression in trauma or cardiopulmonary resuscitation (CPR). In this case series, we describe three patients in whom large endovascular stents were placed to treat significant stenosis of the aorta, the aortic arch or the venous system of the inferior vena cava close to the atrium. In all patients, CPR was necessary during their clinical course for various reasons; after adequate CPR, including appropriate chest compression all patients survived the initial resuscitation phase. Clinical, echocardiographic as well as radiologic re-evaluation after resuscitation revealed significant stent distortion, compression, displacement or additional vascular injury. The possibility of mechanical deformation of large endovascular stents needs to be considered and recognized when performing CPR; if CPR is successful, immediate re-evaluation of the implanted stents--if possible by biplane fluoroscopy--seems mandatory.