Histological Findings and Predictors of Cerebral Debris From Transcatheter Aortic Valve Replacement: The ALSTER Experience

Abstract

BackgroundHistopathological analyses of debris captured by a cerebral protection system during transcatheter aortic valve replacement have been reported, but the origin of the captured debris was not determined and risk factors were not defined.Methods and ResultsEmbolic debris was analyzed from 322 filters used in a dual‐cerebral‐filter protection system implemented during transcatheter aortic valve replacement for 161 patients (mean age 81 years, 82 male [51%], logistic EuroSCORE 19% [interquartile range 12–31%]). The debris capture rate was high, with debris from 97% of all patients (156 of 161). No differences by filter location were found (brachiocephalic trunk 86% [139 of 161], left carotid artery 91% [147 of 161]; adjusted P=0.999). Five prevalent types of debris were identified: thrombus (91%), arterial wall tissue (68%), valve tissue (53%), calcification (46%), and foreign material (30%). Female sex (P=0.0287, odds ratio 1.364, 95% CI 1.032–1.812) and diabetes mellitus (P=0.0116, odds ratio 1.474, 95% CI 1.089–2.001) were significant risk factors for embolic debris. Additional analysis showed significantly more valve tissue in patients with predilation (P=0.0294). Stroke and transient ischemic attack rates were 0.6% each (1 of 161).ConclusionThis study showed a high rate of embolic debris consisting of typical anatomic structures known to be altered in patients with aortic stenosis undergoing transcatheter aortic valve replacement. Female patients with diabetes mellitus have increased risk of embolic debris and should be protected by a cerebral protection system during transcatheter aortic valve replacement. Because valve tissue embolizes more often in patients with predilation, procedural planning should consider this finding. Both cerebral arteries (brachiocephalic trunk, left carotid artery) should be protected in the same way.

Cerebral Protection During Catheter Ablation of Ventricular Tachycardia in Patients With Ischemic Heart Disease

“…In >90% of cases this thrombus material was attached to tissue and/or foreign material. The rate of acute thrombus material is in line with the data from other studies utilizing the Sentinel CPS in endovascular procedures (74%–100%) 10, 12, 14, 15. The thrombogenicity of endovascular catheters cannot be avoided completely, yet an ACT level >300 s should be achieved in every left‐sided procedure, especially in long‐lasting procedures such as VT ablation.…”

“…Since calcification is 1 major reason for aortic stenosis, it is not surprising that the rate of calcified debris observed during TAVR and valve‐in‐valve procedures was reported to be much higher (46%–73%),14, 15 whereas for MitraClip and LAA closure procedures no calcified debris was found 12, 13…”

“…It is noteworthy that the Sentinel CPS does not protect the left vertebral and subclavian arteries. The placement of the CPS was performed as previously described 12, 13, 14, 15. Briefly, before device placement, the anatomy of the aortic branches was visualized by angiography with a pigtail catheter placed in the ascending aorta.…”

Cerebral embolic protection systems for transcatheter aortic valve replacement

“…TAVR source of cerebral emboli is multiple in origin and includes friable aorta, heavily calcified aortic arch and stenotic valve. These areas strictly correspond with the manipulations during pre‐, post‐dilatation and implantation itself, in particular in case of repositioning . Over the last few years the totality of evidence concluded from several cerebral embolic protection studies with TAVR have shown consistent device safety and improvement in clinical outcomes and neuroimaging findings compared to control subjects .…”

Hydrophilic Polymer Embolism: An Update for Physicians

“…A recent analysis of material captured through use of an embolic protection device during mitral valve repair showed that polymer embolism occurred as frequently as acute thromboembolism (86%), with native tissue emboli (64%) and organizing thrombi (29%) noted less often 18 . Frequent polymer coating emboli have also been affiliated with other percutaneous procedures 19,20 . Thus, polymer embolism should be included in the differential of unanticipated ischemic or inflammatory complications as well as unexplained vasculopathies occurring during the post-procedural clinical setting.…”