Effects of Anti-vitamin k oral anticoagulants on bone and cardiovascular health

Warfarin use is associated with higher aortic bioprosthetic 18F-fluoride PET uptake

BACKGROUND

Prevalence of bioprosthetic valve degeneration (BVD) is rising as the use of bioprosthetic aortic valves increases. Detecting early signs of BVD remains a challenge, with conventional imaging methods often failing to identify early deterioration stages. 18F-fuoride positron emission tomography (PET-CT) is an emerging technique that offers promising prospects to detect subclinical BVD. This study aimed to compare early PET parameters of fluoride uptake with echocardiographic hemodynamic parameters and compare outcomes according to anticoagulation in patients who received bioprosthetic valves.

METHODS

This is a sub-study of the ANTIPRO clinical trial, which involved patients undergoing surgical aortic valve replacement (SAVR) with a porcine bioprosthesis and randomized them into anticoagulated and non-anticoagulated groups. Hemodynamic changes were assessed by transthoracic echocardiography (TTE), while 18F-fluoride PET-CT quantified fluoride uptake and divided the patients in two groups: high-uptake and low-uptake. Mean and maximum gradients by TTE at three years were compared between the two uptake groups. Fluoride uptake was also compared between the anticoagulated and control groups.

RESULTS

We found no significant differences in transprosthetic gradients between high-uptake(21.4 ± 8.6 mmHg) and low-uptake(17.3 ± 11.2 mmHg.p = 0.244) PET-defined groups in this specific timeframe. Notably, anticoagulated patients exhibited significantly risk of higher fluoride uptake(OR = 4.34;95%CI:1.04-18.21.p = 0.045).

CONCLUSIONS

No association was found between fluoride uptake and hemodynamic evaluation. Anticoagulation was associated with higher fluoride uptake. These findings highlight the emerging role of PET-CT in studying bioprosthetic aortic valves and emphasize the need for extended follow-up to evaluate the impact of anticoagulation on valve degeneration.

SNF472: a novel therapeutic agent for vascular calcification and calciphylaxis

Vascular calcification is a common complication in patients with chronic kidney disease (CKD) and is strongly associated with an increased risk of cardiovascular events and all-cause mortality. Calciphylaxis is a specific and life-threatening manifestation of vascular calcifications that usually affects individuals with advanced kidney function impairment or those undergoing dialysis. Currently, the treatment of vascular calcification and calciphylaxis in CKD lacks approved treatments and focuses on controlling risk factors. SNF472, the intravenous formulation of myo-inositol hexaphosphate, is a novel vascular calcification inhibitor currently undergoing phase 3 clinical trials, demonstrating its ability to directly inhibit the formation of calcium and phosphorus crystals, thereby blocking the production and deposition of ectopic calcium. The efficacy and safety of SNF472 in inhibiting vascular calcification have been confirmed in recent clinical studies. This review summarizes the results of studies related to SNF472 to provide a comprehensive overview of its mechanism of action, efficacy, safety, and ongoing clinical studies.

Direct-Acting Oral Anticoagulant/Vitamin K Antagonists: Do They Affect the Trabecular and Cortical Structure of the Mandible?

BACKGROUND

This study aimed to evaluate the mandibular bone structure of patients using oral anticoagulants (OACs) vitamin K antagonist drugs (warfarin) and other OACs including direct oral anticoagulants [(DOACs) apixaban, rivaroxaban, dabigatran, edoxaban]. Analyses were based upon the fractal dimension (FD), the panoramic mandibular index (PMI) and the Klemetti index (KI), which is also known as the mandibular cortical index (MCI).

METHODOLOGY

Ninety participants were divided into three groups: group 1: 30 systemically healthy individuals who had not used any anticoagulants before, group 2: 30 individuals using warfarin, and group 3: 30 individuals using DOACs. FD was used to analyze trabecular bone architecture in the condyle, angle, and two sites in the alveolar bone. PMI was used to evaluate the quantity of cortical bone and KI was used to evaluate the cortical bone quality.

RESULTS

There was no difference between the groups regarding FD analysis and KI; however, a difference was found between groups 1, 2, and 3 in the PMI (P≤ 0.001). The PMI in group 1 was higher than in groups 2 and 3.

CONCLUSION

Mandibular radiomorphometric indices can be used on panoramic radiographs to evaluate the quantity of mandibular cortical bone in patients using oral anticoagulants.

Oral anticoagulant treatment and risk of kidney disease-a nationwide, population-based cohort study

Background

Direct oral anticoagulants (DOACs) are recommended as first-line treatment of atrial fibrillation. Whether DOAC use is associated with lower risks of kidney complications compared with vitamin K antagonists (VKAs) remains unclear. We examined this association in a nationwide, population-based cohort study.

Methods

We conducted a cohort study including patients initiating oral anticoagulant treatment within 3 months after an atrial fibrillation diagnosis in Denmark during 2012-18. Using routinely collected creatinine measurements from laboratory databases, we followed patients in an intention-to-treat approach for acute kidney injury (AKI) and chronic kidney disease (CKD) progression. We used propensity-score weighting to balance baseline confounders, computed weighted risks and weighted hazard ratios (HRs) with 95% confidence intervals (CIs) comparing DOACs with VKAs. We performed several subgroup analyses and a per-protocol analysis.

Results

We included 32 781 persons with atrial fibrillation initiating oral anticoagulation (77% initiating DOACs). The median age was 75 years, 25% had a baseline estimated glomerular filtration rate <60 mL/min/1.73 m2, and median follow-up was 2.3 (interquartile range 1.1-3.9) years. The weighted 1-year risks of AKI were 13.6% in DOAC users and 15.0% in VKA users (HR 0.86, 95% CI 0.82; 0.91). The weighted 5-year risks of CKD progression were 13.9% in DOAC users and 15.4% in VKA users (HR 0.85, 95% CI 0.79; 0.92). Results were similar across subgroups and in the per-protocol analysis.

Conclusions

Initiation of DOACs was associated with a decreased risk of AKI and CKD progression compared with VKAs. Despite the potential limitations of observational studies, our findings support the need for increased clinical awareness to prevent kidney complications among patients who initiate oral anticoagulants.

Periostin in Osteoporosis and Cardiovascular Disease

Context

Osteoporosis (OP) and cardiovascular disease (CVD), prevalent disorders worldwide, often coexist and share common risk factors. The identification of common biomarkers could significantly improve patients' preventive care.

Objectives

The objectives are 1, to review periostin (Postn) involvement in osteoporosis and in CVD, and 2, identify if Postn could be a common biomarker.

Design

This is a scoping review on Postn in OP and CVD.

Methods

Databases were searched, in vitro and in vivo, for publications in English on Postn, bone, and the cardiovascular system, with no limit regarding publication date.

Results

Postn appears as a key factor in OP and CVD. Its role as a potential biomarker in both pathologies is described in recent studies, but a number of limitations have been identified.

Conclusions

Current evidence provides fragmented views on Postn in OP and CVD and does not encapsulate Postn as a common pivotal thread linking these comorbidities. A number of gaps impede highlighting Postn as a common biomarker. There is room for future basic and clinical research with Postn as a marker and a target to provide new therapeutic options for aging patients with concomitant OP and CVD.

Oral Anticoagulation in Patients With Advanced Chronic Kidney Disease and Atrial Fibrillation: Beyond Anticoagulation

The optimal approach to prevent stroke and systemic embolism in patients with advanced chronic kidney disease (CKD) and atrial fibrillation remains unresolved. We conducted a narrative review to explore areas of uncertainty and opportunities for future research. First, the relationship between atrial fibrillation and stroke is more complex in patients with advanced CKD than in the general population. The currently employed risk stratification tools do not adequately discriminate between patients deriving a net benefit and those suffering a net harm from oral anticoagulation. Anticoagulation initiation should probably be more restrictive than is currently advocated by official guidelines. Recent evidence reveals that the superior benefit-risk profile of non-vitamin K antagonist oral anticoagulants (NOACs) vs vitamin K antagonists (VKAs) observed in the general population and in moderate CKD can be extended to advanced CKD. The NOACs yield better protection against stroke, cause less major bleeding, are associated with less acute kidney injury and a slower decline of CKD, and are associated with a lower incidence of cardiovascular events than VKAs. The VKAs may be harmful in CKD patients, in particular in patients with a high bleeding risk and labile international normalized ratio. The better safety and efficacy of NOACs as opposed to VKAs may be particularly evident in advanced CKD as a result of better on-target anticoagulation with NOACs, harmful off-target vascular effects of VKAs, and beneficial off-target vascular effects of NOACs. The intrinsic vasculoprotective effects of NOACs are supported by animal experimental evidence as well as by findings of large clinical trials and may result in use of NOACs beyond their anticoagulant properties.

The association of non-vitamin K antagonist oral anticoagulants vs. warfarin and the risk of fractures for patients with atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

The fracture risks of non-vitamin K antagonist oral anticoagulants (NOACs) vs. warfarin in patients with atrial fibrillation (AF) remain controversial.

METHODS

PubMed, Cochrane Library, EMBASE, Clinical Trials.gov databases for RCTs, and cohort studies were systematically searched from inception to 10 June 2021.

RESULTS

Twelve-two studies met the inclusion criteria and 477,821 patients were included. Warfarin increased the risk of fracture in AF patients compared with NOACs in overall any fracture (RR = 0.79; 95% CI = 0.70-10.88; p = 0.00), osteoporotic fracture (RR = 0.746; 95% CI = 0.630-0.883; p = 0.001). No significant difference was observed in the hip or pelvic fracture, vertebral fracture, extremity fracture, wrist fracture, femoral neck fracture, and ankle fracture. In subgroup analyses based on several aspects, NOACs were associated with a significant reduction in any fracture (standard dosage NOACs, cohort studies, elderly patients, rivaroxaban in RCTs, dabigatran, rivaroxaban, and apixaban in cohort studies), in the hip/pelvic fracture (follow-up time ≤1 year, cohort studies), and osteoporotic fracture (cohort studies).

CONCLUSION

NOACs were associated with a significantly lower risk of any fracture and osteoporotic fracture compared to warfarin. This benefit was also observed in specific NOACs types of dabigatran, rivaroxaban, and apixaban. However, whether NOACs had a less fracture risk than warfarin on the other risk of fractures was still uncertain.

Renal function and mortality in patients with atrial fibrillation

AIM

The aim of this study is to examine the association of the presence of chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR) values with mortality in patients with atrial fibrillation.

METHODS

This posthoc analysis of a randomized controlled trial consisted of hospitalized patients with atrial fibrillation who were followed up for a median of 2.7 years after discharge. Kaplan-Meier curves, multivariate Cox-regression and spline curves were utilized to assess the association of CKD, CKD stages 2-5 according to the KDOQI guidelines, and the continuum of eGFR values with the primary outcome of all-cause death, and the secondary outcome of cardiovascular mortality.

RESULTS

Out of 1064 hospitalized patients with atrial fibrillation, 465 (43.7%) had comorbid CKD. The presence of CKD was associated with an increased risk for both all-cause and cardiovascular mortality following hospitalization [adjusted hazard ratio (aHR): 1.60; 95% confidence intervals (95% CIs): 1.25-2.05 and aHR: 1.74; 95% CI: 1.30-2.33, respectively]. The aHRs for all-cause mortality in CKD stages 2-5, as compared with CKD stage 1 were 2.18, 2.62, 4.20 and 3.38, respectively (all P < 0.05). In spline curve analyses, eGFR values lower than 50 ml/min/1.73 m2 were independent predictors of higher all-cause and cardiovascular mortality.

CONCLUSION

In recently hospitalized patients with atrial fibrillation, the presence of CKD was independently associated with decreased survival, which was significant across CKD stages 2-5, as compared with CKD stage 1. Values of eGFR lower than 50 ml/min/1.73 m2 were incrementally associated with worse prognosis.

Doppler Mean Gradient Is Discordant to Aortic Valve Calcium Scores in Patients with Atrial Fibrillation Undergoing Transcatheter Aortic Valve Replacement

BACKGROUND

Doppler mean gradient (MG) may underestimate aortic stenosis (AS) severity when obtained during atrial fibrillation (AF) because of lower forward flow compared with sinus rhythm (SR). Whether AS is more advanced at the time of referral for aortic valve intervention in AF compared with SR is unknown. The aim of this study was to examine flow-independent computed tomographic aortic valve calcium scores (AVCS) and their concordance to MG in AF versus SR in patients undergoing transcatheter aortic valve replacement (TAVR).

METHODS

Patients who underwent TAVR from 2016 to 2020 for native valve severe AS with left ventricular ejection fraction ≥ 50% were identified from an institutional TAVR database. MGs during AF and SR in high-gradient AS (HGAS) and low-gradient AS (LGAS) were compared with AVCS (AVCS/MG ratio). AVCS were obtained within 90 days of pre-TAVR echocardiography.

RESULTS

Six hundred thirty-three patients were included; median age was 82 years (interquartile range [IQR], 76-86 years), and 46% were women. AF was present in 109 (17%) and SR in 524 (83%) patients during echocardiography. Aortic valve area index was slightly smaller in AF versus SR (0.43 cm²/m² [IQR, 0.39-0.47 cm²/m²] vs 0.46 cm²/m² [IQR, 0.41-0.51 cm²/m²], P = .0003). Stroke volume index, transaortic flow rate, and MG were lower in AF (P < .0001 for all). AVCS were higher in men with AF compared with SR (3,510 Agatston units [AU] [IQR, 2,803-4,030 AU] vs 2,722 AU [IQR, 2,180-3,467 AU], P < .0001) in HGAS but not in LGAS. AVCS were not different in women with AF versus SR. Overall AVCS/MG ratios were higher in AF versus SR in HGAS and LGAS (P < .03 for all), except in women with LGAS.

CONCLUSIONS

AVCS were higher than expected by MG in AF compared with SR. The very high AVCS in men with AF and HGAS at the time of TAVR suggests late diagnosis of severe AS because of underestimated AS severity during progressive AS and/or late referral to TAVR. Additional studies are needed to examine the extent to which echocardiography may be underestimating AS severity in AF.

The Effects of Warfarin and Direct Oral Anticoagulants on Systemic Vascular Calcification: A Review

Warfarin has been utilized for decades as an effective anticoagulant in patients with a history of strong risk factors for venous thromboembolism (VTE). Established adverse effects include bleeding, skin necrosis, teratogenicity during pregnancy, cholesterol embolization, and nephropathy. One of the lesser-known long-term side effects of warfarin is an increase in systemic arterial calcification. This is significant due to the association between vascular calcification and cardiovascular morbidity and mortality. Direct oral anticoagulants (DOACs) have gained prominence in recent years, as they require less frequent monitoring and have a superior side effect profile to warfarin, specifically in relation to major bleeding. The cost and lack of data for DOACs in some disease processes have precluded universal use. Within the last four years, retrospective cohort studies, observational studies, and randomized trials have shown, through different imaging modalities, that multiple DOACs are associated with slower progression of vascular calcification than warfarin. This review highlights the pathophysiology and mechanisms behind vascular calcification due to warfarin and compares the effect of warfarin and DOACs on systemic vasculature.