Ex Vivo Antiplatelet Effects of Oral Anticoagulants.

BACKGROUND: The impact of non-vitamin K antagonist oral anticoagulants (NOACs) on platelet function is still unclear. We conducted a comprehensive ex vivo study aimed at assessing the effect of the four currently marketed NOACs on platelet function. METHODS: We incubated blood samples from healthy donors with concentrations of NOACs (50, 150 and 250 ng/mL), in the range of those achieved in the plasma of patients during therapy. We evaluated generation of thrombin; light transmittance platelet aggregation (LTA) in response to adenosine diphosphate (ADP), thrombin receptor-activating peptide (TRAP), human γ-thrombin (THR) and tissue factor (TF); generation of thromboxane (TX)B2; and expression of protease-activated receptor (PAR)-1 and P-selectin on the platelet surface. RESULTS: All NOACs concentration-dependently reduced thrombin generation compared with control. THR-induced LTA was suppressed by the addition of dabigatran at any concentration, while TF-induced LTA was reduced by factor-Xa inhibitors. ADP- and TRAP-induced LTA was not modified by NOACs. TXB2 generation was reduced by all NOACs, particularly at the highest concentrations. We found a concentration-dependent increase in PAR-1 expression after incubation with dabigatran, mainly at the highest concentrations, but not with FXa inhibitors; P-selectin expression was not changed by any drugs. CONCLUSIONS: Treatment with the NOACs is associated with measurable ex vivo changes in platelet function, arguing for antiplatelet effects beyond the well-known anticoagulant activities of these drugs. There are differences, however, among the NOACs, especially between dabigatran and the FXa inhibitors.

Prognostic significance of right ventricle to pulmonary artery coupling in patients with mitral regurgitation treated with the MitraClip system.

OBJECTIVES: To evaluate the prognostic impact of baseline tricuspid annular plane systolic excursion/pulmonary artery systolic pressure (TAPSE/PASP) ratio, as an expression of the right ventricle-pulmonary artery (RV-PA) coupling, in patients with mitral regurgitation (MR) treated with the MitraClip. BACKGROUND: Impaired RV to PA coupling is considered a marker of RV dysfunction. METHODS: From February 2016 to February 2020, a total of 165 patients were evaluated and stratified in two groups according to a prespecified value of TAPSE/PASP ratio ≤ 0.36. RESULTS: The median patients' age was 79 (men: 62.4%). Sixty-three patients (38.1%) presented TAPSE/PASP ≤ 0.36 and were then compared with patients with TAPSE/PASP > 0.36. Functional MR etiology was more frequent in TAPSE/PASP ≤ 0.36 (71.4%; p = 0.046). Acute technical success was achieved in 92.7% of the population, without any significant difference between the two groups of study and with sustained results at 30-day (device success: 85.5%; procedural success: 84.8%). On multivariate Cox regression analysis, after correction for body mass index, chronic kidney disease and left ventricle ejection fraction ≥30% but <50%, TAPSE/PASP ≤ 0.36 remained a sustained predictor of mortality and hospitalization for heart failure at one year after MitraClip (hazard ratio: 3.87; 95% confidence interval: 1.83-8.22; p ≤ 0.001). Kaplan-Meier all-cause mortality and heart failure hospitalization rates at one year were consequently higher in patients with TAPSE/PASP ≤ 0.36 (39.4% vs. 14.8%; log-rank p ≤ 0.001). CONCLUSION: Baseline TAPSE/PASP ratio seems independently associated with all-cause mortality and heart failure hospitalization after MitraClip both in functional and degenerative MR.

Transcatheter Mitral Valve Repair with the PASCAL System after Early Edge-to-Edge Surgical Failure.

We report the challenging case of percutaneous treatment of early recurrent mitral regurgitation after Alfieri edge-to-edge surgical procedure.

Selection of the Optimal Candidate to MitraClip for Secondary Mitral Regurgitation: Beyond Mitral Valve Morphology.

Secondary mitral regurgitation (MR) occurs despite structurally normal valve apparatus due to an underlying disease of the myocardium leading to disruption of the balance between tethering and closing forces with ensuing failure of leaflet coaptation. In patients with heart failure (HF) and left ventricular dysfunction, secondary MR is independently associated with poor outcome, yet prognostic benefits related to the correction of MR have remained elusive. Surgery is not recommended for the correction of secondary MR outside coronary artery bypass grafting. Percutaneous mitral valve repair (PMVR) with MitraClip implantation has recently evolved as a new transcatheter treatment option of inoperable or high-risk patients with severe MR, with promising results supporting the extension of guideline recommendations. MitraClip is highly effective in reducing secondary MR in HF patients. However, the derived clinical benefit is still controversial as two randomized trials directly comparing PMVR vs. optimal medical therapy in severe secondary MR yielded virtually opposite conclusions. We reviewed current evidence to identify predictors of PMVR-related outcomes in secondary MR useful to improve the timing and the selection of patients who would derive maximal benefit from MitraClip intervention. Beyond mitral valve anatomy, optimal candidate selection should rely on a comprehensive diagnostic workup and a fine-tuned risk stratification process aimed at (i) recognizing the substantial heterogeneity of secondary MR and its complex interaction with the myocardium, (ii) foreseeing hemodynamic consequences of PMVR, (iii) anticipating futility and (iv) improving symptoms, quality of life and overall survival.

Cholesterol Lowering and Stroke: No Longer Room for Pleiotropic Effects of Statins - Confirmation from PCSK9 Inhibitor Studies.

BACKGROUND: The relationship between cholesterol levels and stroke has been much less clear than the relationship between cholesterol levels and coronary heart disease. This is likely mostly due to the inadequate power of older studies and the low intensity of cholesterol-lowering interventions available at the time. Because a reduction in stroke has been, conversely, clearly observed in trials with statins, for long "pleiotropic" effects of such drugs, unrelated to cholesterol lowering, have been invoked. In a previous analysis of all randomized trials of cholesterol-lowering treatments reporting on stroke we had, however, reached the conclusion that any cholesterol lowering is related to a significant reduction of stroke, in a relationship that appeared to exist for both statin and nonstatin cholesterol-lowering interventions. Outcome results of the FOURIER trial with evolocumab, SPIRE-1 and -2 with bococizumab, and ODYSSEY OUTCOMES trial with alirocumab now offer the opportunity of clearly confirming or confuting this concept. METHODS: We here report on an updated meta-regression of the relationship of total cholesterol changes that occur with various drugs or treatments and changes in the risk of stroke compared with control. RESULTS: Relative risk (RR) figure found in FOURIER, SPIRE-1/2, and ODYSSEY OUTCOMES (0.79, 0.60, and 0.79) are extremely close to the RRs of 0.79, 0.79, and 0.84, respectively, predicted by our new meta-regression. CONCLUSIONS: These findings offer definitive proof that the pure total (and low-density lipoprotein) cholesterol lowering, with any available lipid-lowering intervention, reduces stroke risk proportional to the extent of cholesterol reduction, without the need of invoking "pleiotropic" effects of any such treatment.

All cholesterol-lowering interventions are expected to reduce stroke: Confirmatory data from IMPROVE-IT.

The relationship of cholesterol with stroke is much less clear than its relationship with myocardial infarction, thus confounding the interpretation of results with cholesterol-lowering trials (Di Napoli et al., 2002) [1], (De Caterina et al., 2010) [2]). IMPROVE-IT data ((Cannon et al. 2015) [3]), showing a 13.3% reduction in total cholesterol at one year in association with a hazard ratio (HR) of 0.i86 for total stroke during the trial, are very closely aligned with the relative risk of 0.90 predicted based on the totality of lipid lowering interventions ((De Caterina et al., 2016) [4]). We here provide the data from the original trials used to construct this meta-analysis, with the now added additional data from IMPROVE-IT, well-fitting the previously found meta-regression line. These data are important to predict stroke outcomes in currently ongoing trials now testing PCSK9 or cholesterol ester transfer protein inhibitors.

Cholesterol-lowering interventions and stroke: Insights from IMPROVE-IT.

The relationship of cholesterol with stroke is much less clear than its relationship with myocardial infarction, thus confounding the interpretation of results with cholesterol-lowering trials. Because for long time the only lipid-lowering intervention reducing stroke was statins, it has been actually argued that reduction in stroke found in statin trials is not due to statins' ability to reduce LDL cholesterol, but to other "pleiotropic" effects, unrelated to cholesterol lowering. In re-analyzing the relationship of cholesterol lowering versus changes in the risk of stroke in a meta-regression of all cholesterol-lowering interventions, including also non-statin interventions, we had previously reached the opposite conclusion: that some reduction in stroke has to be expected proportional to cholesterol reduction. We had predicted that a 1% reduction of total cholesterol-no matter by what intervention produced-was associated with a 0.8% relative risk reduction of stroke. Data from the recently published Improved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT) now offer a clear proof of this concept, demonstrating that pure cholesterol lowering, as obtained with ezetimibe, plays an important role in reducing stroke. IMPROVE-IT data, showing a 13.3% reduction in total cholesterol at one year in association with a hazard ratio (HR) of 0.86 for total stroke during the trial, are very closely aligned with the relative risk of 0.90 predicted on the basis of the totality of lipid lowering interventions. These data are important to predict stroke outcomes in currently ongoing trials now testing PCSK9 or cholesterol ester transfer protein inhibitors.