Impact of Mitral Annular Calcium and Mitral Stenosis on Outcomes After Transcatheter Aortic Valve Implantation.

Mitral annular calcium (MAC) is a common finding in patients undergoing transcatheter aortic valve implantation (TAVI) and may be associated with mitral stenosis (MAC-MS). Their impact on post-TAVI outcomes remains controversial. We sought to assess the impact of MAC and MAC-MS on clinical outcomes following TAVI. We included 1,177 patients who consecutively underwent TAVI in our institution between January 2008 and May 2018. MAC diagnosis reposed on echocardiogram and computed tomography. The combination of MAC and a mean transmitral gradient ≥ 5 mmHg defined MAC-MS. The study included 1,177 patients, of whom 504 (42.8%) had MAC and 85 (7.2%) had MAC-MS. Patients with and without MAC had similar outcomes except for a higher rate of pacemaker implantation in MAC patients (adjusted HR: 1.32, 95% CI: 1.03-1.69, p = 0.03). The subgroup of patients with severe MAC had similar outcomes. However, MAC-MS was an independent predictor of all-cause mortality at 30 days (adjusted HR: 2.30, 95% CI: 1.08-4.86, p = 0.03) and 1 year (adjusted HR: 1.73, 95% CI: 1.04-2.89, p = 0.04). In conclusion, MAC is present in nearly half of the patients treated with TAVI but MAC-MS is far less frequent. In itself, even severe, MAC does not influence outcomes while MAC-MS is an independent predictor of all-cause 1-year mortality. Measurement of mean transmitral gradient identifies patients with MAC at high risk after TAVI.

Causes and temporal trends in procedural deaths after transcatheter aortic valve implantation.

BACKGROUND: The causes of procedural deaths after transcatheter aortic valve implantation (TAVI) have been scarcely detailed. AIMS: To assess these causes and their temporal trends since the beginning of the TAVI era. METHODS: From October 2006 to April 2014, 601 consecutive high-risk/inoperable patients with severe aortic stenosis underwent TAVI using the Edwards SAPIEN or SAPIEN XT or the Medtronic CoreValve. The transfemoral route was the default approach; the transapical or left subclavian approaches were alternative options. Patients were divided into three tertiles according to the date of the procedure. RESULTS: Procedural death occurred in 45 patients (7.5%), with a median±standard deviation age of 83±7 years; 23 were men (51%) and the mean logistic EuroSCORE was 26±16%. The main cause of death was heart failure (n=19, 42%), followed by cardiac rupture (n=12, 27%), intensive care complications (n=9, 20%) and vascular complications (n=5, 11%). The mortality rate was higher after transapical than transfemoral TAVI (17% vs. 5%; P<0.001). The mortality rate decreased over time (11.9% in the first tertile, 6.0% in the second and 4.5% in the third [P=0.007]), driven by a reduction in heart failure-related deaths (6.5% in the first tertile vs. 1.5% in the third; P=0.011). Vascular complication-related deaths disappeared in the third tertile. However, there was no decrease in deaths related to cardiac ruptures and intensive care complications. CONCLUSIONS: The procedural mortality rate of TAVI decreased over time, driven by the decrease in heart failure-related deaths. However, efforts should continue to prevent cardiac ruptures and improve the outcomes of patients requiring intensive care after TAVI.

Peristrut microhemorrhages: a possible cause of in-stent neoatherosclerosis?

BACKGROUND: In-stent neoatherosclerosis is characterized by the delayed appearance of markers of atheroma in the subintima, but the pathophysiology underlying this new disease entity remains unclear. METHODS AND RESULTS: We collected 20 human coronary artery stents by removal from explanted hearts. The mean duration of stent implantation was 34 months. In all samples, neoatherosclerosis was detected, particularly in peristrut areas. It consisted of foam cells and cholesterol clefts, with or without calcification, associated with neovascularization. Iron and glycophorin-A were present in peristrut areas, as well as autofluorescent ceroids. Moreover, in response to neoatherosclerosis, tertiary lymphoid organs (tissue lymphoid clusters) often developed in the adventitia. Some of these features could be reproduced in an experimental carotid stenting model in rabbits fed a high-cholesterol diet. Foam cells were present in all samples, and peristrut red blood cells (RBCs) were also detected, as shown by iron deposits and Bandeiraea simplicifiola isolectin-B4 staining of RBC membranes. Finally, in silico models were used to evaluate the compliance mismatch between the rigid struts and the distensible arterial wall using finite element analysis. They show that stenting approximately doubles the local von Mises stress in the intimal layer. CONCLUSIONS: We show here that stent implantation both in human and in rabbit arteries is characterized by local peristrut microhemorrhages and finally by both cholesterol accumulation and oxidation, triggering together in-stent neoatherosclerosis. Our data indicate that these processes are likely initiated by an increased mechanical stress due to the compliance mismatch between the rigid stent and the soft wall.