Medtronic warns delivery catheter for self-expanding TAVR system may cause severe vascular trauma

Medtronic sent an advisory letter to physicians and healthcare professionals warning of the potential for vascular trauma when using a delivery catheter system for a self-expanding transcatheter aortic valve replacement system.

In the letter, the company stated that while reports of vascular trauma associated with the delivery catheter (Enveo R) used with the TAVR system (CoreValve Evolut R) were infrequent (0.136%; 39 events), some outcomes have been serious, including patient deaths (0.078%; 19 events).

Medtronic stated that the observed vascular-trauma rate is lower than that observed in the Transcatheter Valve Therapy registry reports of annular dissection (0.2%) and aortic disruption (0.4%) published in the Journal of the American College of Cardiology.

However, the company stated, the potential severity of these events spurred an investigation resulting in recommendations to lessen the rate of vascular trauma.

The company advised that combinations of two or more of the following anatomy considerations raise vascular-trauma risk: the plane of the aortic annulus (extent of the aortic arch curvature or horizontal heart); combined anterior-posterior and lateral thoracic and abdominal aortic tortuosity; tight curvature of the aortic arch (severe bends); presence of an aneurysmal ascending aorta; and significant calcification in the aortic arch (which may be affected by level, orientation and size).

According to the letter, during procedural use, operators should magnify images sufficiently to visualize the capsule tip relative to the patient’s vasculature. Also, the company stated, passage should not be forced if the delivery-system tip bends in a different direction relative to the delivery-system capsule; instead, the operator should retract the delivery system into a straight portion of the descending aorta, reorienting it by rotating the delivery system 90° and carefully reinitiating passage.

If significant resistance is seen during advancement of the delivery system, passage should not be forced, the company stated. Instead, according to the letter, operators should employ increased fluoroscopic magnification for assessing vasculature; if no damage is evident, the operator should retract the delivery system into a straight portion of the descending aorta and consider the following: reorientation the delivery system while carefully reinitiating passage; selection of a stiffer guidewire such as Lunderquist; use of an alternative commercially available device; and use of a non-transfemoral alternate access route.