Efficacy and Safety of Rivaroxaban Versus Aspirin in Embolic Stroke of Undetermined Source and Carotid Atherosclerosis.

Background and Purpose- The sources of emboli in patients with embolic stroke of undetermined source (ESUS) are multiple and may not respond uniformly to anticoagulation. In this exploratory subgroup analysis of patients with carotid atherosclerosis in the NAVIGATE (New Approach Rivaroxaban Inhibition of Factor Xa in a Global Trial Versus ASA to Prevent Embolism)-ESUS trial, we assessed whether the treatment effect in this subgroup is consistent with the overall trial population and investigated the association of carotid atherosclerosis with recurrent ischemic stroke. Methods- Carotid atherosclerosis was analyzed either as the presence of mild (ie, 20%-49%) atherosclerotic stenosis or, separately, as the presence of carotid plaque. Primary efficacy outcome was ischemic stroke recurrence. Safety outcomes were major bleeding and symptomatic intracerebral bleeding. Results- Carotid plaque was present in 40% of participants and mild carotid stenosis in 11%. There was no significant difference in ischemic stroke recurrence between rivaroxaban- and aspirin-treated patients among 490 patients with carotid stenosis (5.0 versus 5.9/100 patient-years, respectively, hazard ratio [HR], 0.85; 95% CI, 0.39-1.87; P for interaction of treatment effect with patients without carotid stenosis 0.78) and among 2905 patients with carotid plaques (5.9 versus 4.9/100 patient-years, respectively, HR, 1.20; 95% CI, 0.86-1.68; P for interaction of treatment effect with patients without carotid stenosis 0.2). Among patients with carotid plaque, major bleeding was more frequent in rivaroxaban-treated patients compared with aspirin-treated (2.0 versus 0.5/100 patient-years, HR, 3.75; 95% CI, 1.63-8.65). Patients with carotid stenosis had similar rate of ischemic stroke recurrence compared with those without (5.4 versus 4.9/100 patient-years, respectively, HR, 1.11; 95% CI, 0.73-1.69), but there was a strong trend of higher rate of ischemic stroke recurrence in patients with carotid plaque compared with those without (5.4 versus 4.3/100 patient-years, respectively, HR, 1.23; 95% CI, 0.99-1.54). Conclusions- In ESUS patients with carotid atherosclerosis, we found no difference in efficacy between rivaroxaban and aspirin for prevention of recurrent stroke, but aspirin was safer, consistent with the overall trial results. Carotid plaque was much more often present ipsilateral to the qualifying ischemic stroke than contralateral, supporting an important etiological role of nonstenotic carotid disease in ESUS. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT02313909.

Clopidogrel Therapy in Patients with Cardiovascular Disease Undergoing Transurethral Resection of the Prostate: A Step Towards Individualization.

OBJECTIVES: The objective of this study was to test platelet function pre- and peri-operatively in clopidogrel-treated patients undergoing transurethral resection of the prostate. METHODS: This was a pilot study involving 20 male patients treated with clopidogrel (75 mg/day) for the secondary prevention of cardiovascular disease and scheduled for elective transurethral resection of the prostate. Platelet function testing with light transmittance aggregometry in platelet-rich plasma of four samples (T0, T1, T2, and T3 drawn on the same day, 3 and 7 days of clopidogrel cessation and 24-h post-operatively, respectively) was performed and evaluated in each patient. P-selectin membrane expression was evaluated using monoclonal antibodies. RESULTS: The platelet response to adenosine diphosphate 5 µΜ and 20 µΜ at T0 were 42 ± 15 and 60 ± 14%, respectively. After discontinuation of clopidogrel, corresponding maximum aggregation values at T1 were 60 ± 16 and 74 ± 14%, and increased to 69 ± 16 and 79 ± 18% at T2. No significant difference in platelet aggregation values were noted between T1 and T2, while similar aggregation values were recorded at T3. CONCLUSIONS: Our findings indicate that in patients undergoing transurethral resection of the prostate, platelet activation is similar 3 and 7 days from clopidogrel cessation. These results may be of relevance in subjects at increased thrombotic risk prior to a surgical procedure carrying a high-bleeding risk.

Vitamin D and stroke: promise for prevention and better outcome.

The role of vitamin D (VitD) has recently been expanded beyond bone homeostasis and regulation of calcium levels. VitD deficiency has been proposed as a new risk factor for cardiovascular disease, including stroke. Low 25(OH)VitD levels are very common among post-stroke patients, probably due to their limited mobility and decreased sunlight exposure along with a higher prevalence of malnutrition, and they have been associated with previous and incident cerebrovascular events. Contributing mechanisms have been linked to the association of VitD deficiency with the presence of hypertension, diabetes mellitus and atherosclerosis. Moreover, there is experimental evidence demonstrating that VitD exerts neuroprotective effects, such as stimulation of neurotrophic factors, quenching of oxidative hyperactivity and regulation of neuronal death, as well as antithrombotic properties. It is plausible that VitD supplementation could be a beneficial intervention for the prevention and/or treatment of cerebrovascular disease possibly by decreasing the aforementioned cerebrovascular risk factors and simultaneously by improving neurologic and cognitive functions, thereby reducing falls and fractures in post-stroke patients. However, study results are still conflicting and data from large, randomized clinical trials are needed to clarify these speculations.

Rosuvastatin-associated adverse effects and drug-drug interactions in the clinical setting of dyslipidemia.

HMG-CoA reductase inhibitors (statins) are the mainstay in the pharmacologic management of dyslipidemia. Since they are widely prescribed, their safety remains an issue of concern. Rosuvastatin has been proven to be efficacious in improving serum lipid profiles. Recently published data from the JUPITER study confirmed the efficacy of this statin in primary prevention for older patients with multiple risk factors and evidence of inflammation. Rosuvastatin exhibits high hydrophilicity and hepatoselectivity, as well as low systemic bioavailability, while undergoing minimal metabolism via the cytochrome P450 system. Therefore, rosuvastatin has an interesting pharmacokinetic profile that is different from that of other statins. However, it remains to be established whether this may translate into a better safety profile and fewer drug-drug interactions for this statin compared with others. Herein, we review evidence with regard to the safety of this statin as well as its interactions with agents commonly prescribed in the clinical setting. As with other statins, rosuvastatin treatment is associated with relatively low rates of severe myopathy, rhabdomyolysis, and renal failure. Asymptomatic liver enzyme elevations occur with rosuvastatin at a similarly low incidence as with other statins. Rosuvastatin treatment has also been associated with adverse effects related to the gastrointestinal tract and central nervous system, which are also commonly observed with many other drugs. Proteinuria induced by rosuvastatin is likely to be associated with a statin-provoked inhibition of low-molecular-weight protein reabsorption by the renal tubules. Higher doses of rosuvastatin have been associated with cases of renal failure. Also, the co-administration of rosuvastatin with drugs that increase rosuvastatin blood levels may be deleterious for the kidney. Furthermore, rhabdomyolysis, considered a class effect of statins, is known to involve renal damage. Concerns have been raised by findings from the JUPITER study suggesting that rosuvastatin may slightly increase the incidence of physician-reported diabetes mellitus, as well as the levels of glycated hemoglobin in older patients with multiple risk factors and low-grade inflammation. Clinical trials proposed no increase in the incidence of neoplasias with rosuvastatin treatment compared with placebo. Drugs that antagonize organic anion transporter protein 1B1-mediated hepatic uptake of rosuvastatin are more likely to interact with this statin. Clinicians should be cautious when rosuvastatin is co-administered with vitamin K antagonists, cyclosporine (ciclosporin), gemfibrozil, and antiretroviral agents since a potential pharmacokinetic interaction with those drugs may increase the risk of toxicity. On the other hand, rosuvastatin combination treatment with fenofibrate, ezetimibe, omega-3-fatty acids, antifungal azoles, rifampin (rifampicin), or clopidogrel seems to be safe, as there is no evidence to support any pharmacokinetic or pharmacodynamic interaction of rosuvastatin with any of these drugs. Rosuvastatin therefore appears to be relatively safe and well tolerated, sharing the adverse effects that are considered class effects of statins. Practitioners of all medical practices should be alert when rosuvastatin is prescribed concomitantly with agents that may increase the risk of rosuvastatin-associated toxicity.