Complications
Operators have to be prepared for all emergencies when performing transcatheter aortic valve replacement (TAVR). Complications should be managed by the team with predefined and discussed protocols, and these will be determined by local expertise. Bailout equipment should be readily accessible.
Common complications during and after TAVR and how to address them are listed here:
Unexplained hypotension —Look for etiology, start fluids, and add vasoactive medications to maintain blood pressure (BP). Common causes of hypotension include vascular injury with perforation, retroperitoneal bleed, coronary occlusion, acute severe aortic insufficiency, pericardial effusion with tamponade, and conduction abnormalities. If hypotension occurs at sheath insertion or removal, suspect peripheral perforation; an early angiography to define iliac anatomy is essential. If hypotension occurs after passage of the stiff wire into the left ventricle (LV), consider severe mitral insufficiency and LV perforation, as etiologies and echocardiography are essential to diagnosis. Consider early cardiopulmonary bypass if not responsive to fluids/vasopressors and acute cardiac injury is suspected.
Vascular complications —These range from failure of percutaneous closure devices to aortic rupture. These also include bleeding and other complications like dissection, pseudoaneurysm, and fistulas. The evolution of TAVR devices with a smaller-caliber access sheath has decreased the incidence of vascular complications.
After Perclose suture deployment, a mild stenosis at the site of suture deployment is normally seen. However, if the Perclose sutures are deployed at acute angles, a larger stenosis can be seen, which can lead to claudication. Avoidance of such complications would require careful access in a vessel that does not have anterior calcification under fluoroscopic and ultrasound guidance. Carefully placing the Perclose devices after making a 4- to 5-mm skin incision and spreading the tissue in order for the Perclose to be advanced safely and deployed are key. This procedure is described in Chapter 2 .
Iliac dissection —Usually seen postprocedure on the completion aortogram. This may manifest as a sluggish flow down the affected iliac artery or complete occlusion of flow. Occasionally, it may not be flow limiting. If it is non–flow limiting and small, it may be managed conservatively with no intervention. If there is sluggish flow down the iliac or abrupt occlusion of the iliac, endovascular intervention is required with angioplasty and stenting. Fig. 10.1 describes management of an iliac dissection with placement of covered stents, with restoration of flow.
Iliac perforation —In contrast to iliac dissection, this is usually marked by hypotension and hemodynamic instability. Usually, the aortogram reveals extravasation of contrast into the retroperitoneum. Prompt recognition is crucial. Management involves balloon tamponade of the perforation, usually in the iliac artery. Occasionally, an aortic occlusion balloon may need to be placed in the descending aorta. Once the balloon tamponade is achieved, management of the perforation will either be via placement of a covered stent to seal the perforation, if feasible, or vascular surgery intervention with open repair in the case of extensive perforation or anatomic unsuitability for covered stent placement ( Fig. 10.2 ).
Vascular thrombosis —This can occur with inadequate anticoagulation or in situations where the large-bore sheath is left in place for a long period. This is prevented by ensuring adequate anticoagulation and prompt removal of the large-bore sheath at the completion of the case. If thrombosis occurs, endovascular management with catheter-directed thrombolysis with or without aspiration thrombectomy may be performed.
Access site occlusion —This can occur when the Perclose suture occludes the common femoral artery, leading to ischemia of the affected limb. Risk factors include significant plaque/calcification at the access site and smaller-caliber vessels. Balloon angioplasty to relieve the obstruction may be performed; however, occasionally this may require open repair ( Fig. 10.3 ).