Comparison of Ticagrelor Versus Clopidogrel on Cerebrovascular Microembolic Events and Platelet Inhibition during Transcatheter Aortic Valve Implantation.

The impact of the antiplatelet regimen and the extent of associated platelet inhibition on cerebrovascular microembolic events during transcatheter aortic valve implantation (TAVI) are unknown. Our aim was to evaluate the effects of ticagrelor versus clopidogrel and of platelet inhibition on the number of cerebrovascular microembolic events in patients undergoing TAVI. Patients scheduled for TAVI were randomized previous to the procedure to either aspirin and ticagrelor or to aspirin and clopidogrel. Platelet inhibition was expressed in P2Y12 reaction units (PRU) and percentage of inhibition. High intensity transient signals (HITS) were assessed with transcranial Doppler (TCD). Safety outcomes were recorded according to the VARC-2 definitions. Among 90 patients randomized, 6 had an inadequate TCD signal. The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) (42 patients) than in the clopidogrel group (723.5 [471.5, 875.0]) (42 patients), p <0.001. After adjusting for the duration of the procedure, diabetes, extra-cardiac arteriopathy, BMI, hypertension, aortic valve calcium content, procedural ACT, and pre-implantation balloon valvuloplasty, patients on ticagrelor had on average 256.8 (95% CI: [-335.7, -176.5]) fewer total procedural HITS than patients on clopidogrel. Platelet inhibition was greater with ticagrelor 26 [10, 74.5] PRU than with clopidogrel 207.5 (120 to 236.2) PRU, p <0.001, and correlated significantly with procedural HITS (r = 0.5, p <0.05). In conclusion, ticagrelor resulted in fewer procedural HITS, compared with clopidogrel, in patients undergoing TAVI, while achieving greater platelet inhibition.

Pre-Dilatation Versus No Pre-Dilatation for Implantation of a Self-Expanding Valve in All Comers Undergoing TAVR: The DIRECT Trial.

OBJECTIVES: The aim of this study was to compare the implantation of a self-expanding valve with or without balloon aortic valvuloplasty (BAV) in an open-label, noninferiority, randomized trial. BACKGROUND: There are no randomized studies comparing the implantation of a self-expanding valve with (pre-BAV) or without BAV. METHODS: Consecutive patients with severe aortic stenosis were randomly assigned to undergo transcatheter aortic valve replacement with the use of self-expanding prostheses with (pre-BAV) or without (no-BAV) pre-dilatation. The primary endpoint was device success according to the Valve Academic Research Consortium 2 criteria. Secondary endpoints included periprocedural mortality and stroke, new permanent pacemaker implantation, vascular complications, and 1-year mortality. The trial was scheduled to show noninferiority (Δ = 15%) of the direct versus the pre-BAV approach. RESULTS: A total of 171 patients were randomized at 4 centers. Of these, 86 underwent transcatheter aortic valve replacement with pre-dilatation and 85 without. Device success was noninferior in the no-BAV group compared with the pre-BAV group (65 of 85 [76.5%] for no-BAV vs. 64 of 86 [74.4%] for pre-BAV; mean difference 2.1%; 90% confidence interval: -8.9% to 13%). In the no-BAV group, 25 patients (29.4%) underwent post-balloon dilatation, and in the pre-BAV group, 13 patients (15.1%) underwent post-balloon dilatation (p = 0.03). Regarding major vascular complications and permanent pacemaker implantation, there was no difference between the 2 groups (log-rank p = 0.49, log-rank p = 0.54). In 1-month completed follow-up for all patients, there was 1 periprocedural stroke (0.5%), without any deaths. CONCLUSIONS: Direct, without balloon pre-dilatation, transcatheter aortic valve replacement with a self-expanding prosthesis system is noninferior to the pre-dilatation procedure. Lower post-dilatation rates were encountered in the group with pre-dilatation. (The Predilatation in Transcatheter Aortic Valve Implantation Trial [DIRECT]; NCT02448927).

Platelet to lymphocyte ratio in acute aortic dissection.

BACKGROUND: Inflammation plays an important role in the initiation and progression of acute aortic dissection (AAD). New inflammatory indices derived from full cell blood count and its differential may be associated with increased risk. We evaluated platelet-lymphocyte (PLR), red cell distribution width (RDW) and RDW/PLT's (platelets) (RPR) in AAD. METHODS: We studied 120 consecutive patients with AAD type I admitted for emergency surgery (group I), 121 consecutive patients with aortic aneurysms of the ascending aorta prior to elective repair (group II) and 121 controls (group III), age and sex matched. RESULTS: PLR was significantly higher in group I vs both groups II and III (P < .001). There was an excellent correlation of PLR with neutrophil/lymphocyte ratio (NLR) in all three groups (P < .001 for all). After adjustment for hemoglobin, RDW did not differ but RPR remained significantly higher in group I compared to groups II and III (P < .001). The best cutoff value of PLR to predict dissection was 159 with 53% sensitivity and 86% specificity. No association between PLR, RDW, and RPR and mortality in group I was found. CONCLUSIONS: Indices derived from full cell blood count may provide diagnostic information in patients with AAD; whether these indices may contribute to prognosis assessment should be further investigated.