Inappropriate Underdosing of Direct Oral Anticoagulants in Atrial Fibrillation Patients: Results from the START2-AF Registry

Background: Direct oral anticoagulants (DOACs) are recommended for stroke prevention in non-valvular atrial fibrillation (NVAF) patients. We aimed to describe the prevalence of inappropriate DOACs dose prescription in the START2-AF Registry, the outcomes according to the appropriateness of the dosage, and the factors associated with inappropriate dose prescription. Methods: Patients' demographics and clinical data were prospectively collected as electronic files in an anonymous form on the website of the START2-Registry; DOACs dosage was determined to be appropriate when prescribed according to the European Heart Rhythm Association Guidelines. Results: We included 5943 NVAF patients on DOACs; 2572 (46.3%) were female patients. The standard dose (SD) was prescribed to 56.9% of patients and the low dose (LD) was prescribed to 43.1% of patients; 38.9% of all NVAF patients received an inappropriate LD DOAC and 0.3% received inappropriate SD. Patients treated with LD DOAC had a significantly higher rate of all bleedings (RR 1.5; 95% CI 1.2-2.0), major bleedings (RR 1.8; 95% CI 1.3-1.7), and mortality (RR 2.8; 95% CI 1.9-4.1) with respect to patients treated with SD DOAC. No difference was found among patients treated with appropriate and inappropriate LD regarding bleeding, thrombotic, and mortality rates. Age, body weight <60 kg, and renal failure were significantly associated with inappropriate LD DOAC prescription. Conclusions: Inappropriate LD DOACs in NVAF patients is not associated with a reduction in bleeding risk, nor with an increased thrombotic risk. Instead, it is associated with higher mortality rate, suggesting that, in clinical practice, underdosing is preferred for patients at particularly high risk for adverse events.

The Effectiveness of Ablation Therapy for Atrial Fibrillation: A Systematic Review

It is expected that the prevalence of atrial fibrillation (AF), the most prevalent cardiac arrhythmia among people aged 65 to 85, would be mostly classified using the CHAS2DS2-VASc approach for anticoagulation therapy. A high number of people in the entire world will be living with AF by 2030. Long-term follow-up data are sparse, although radiofrequency catheter ablation (CA) for symptomatic AF patients has the potential to be a curative therapy. Although women are referred later and less often than men, the outcomes following ablation are comparable across both genders. Health-related quality of life suffers from AF, and patients often find themselves less active as a result of their condition. AF may have a wide variety of symptoms and signs from the clinic's point of view. Women are more likely to exhibit symptoms than men; one reason for this is that women have an average QT interval that is 10-20 milliseconds longer than men, which is more likely to exacerbate tachycardia symptoms. In search of medical databases for relevant medical literature, we looked at PubMed/Medline, the Cochrane Library, and Google Scholar. Ten publications were gathered after the papers were located, assessed, and qualifying criteria applied were used to select them. The finished articles were done to give an overview of the effectiveness of ablation therapy for AF. Some studies showed that there was no statistical significance between invasive and pharmacological treatments. Other research found no difference in the recurrence of atrial arrhythmia between pulmonary vein isolation (PVI) CA alone and PVI + enhancement magnetic resonance imaging (MRI)-guided fibrosis ablation in individuals with persistent AF. The oldest individuals in studies comparing CA to medical treatment for AF demonstrated no improvement in prognosis after CA. Also, complications from therapy and CA's efficacy in preventing future atrial arrhythmias were similarly low across all age groups. Based on the above, we concluded that more studies are required to establish the most effective approach to treating AF to apply it in daily practice and gain more knowledge about it.

A Massive Renal Infarction Due to Atheroemboli: A Case Report

The symptoms of acute renal infarction (ARI) caused by atheroemboli are vague, making it rare. Early diagnosis of renal infarction can be made through contrast-enhanced CT of the abdomen. However, diagnosing atheroemboli is more challenging. Kidney biopsy is the most accurate method to determine the cause, but it may not always be available in clinical settings. In cases where a thrombectomy is performed, white substances in thrombus aspiration or the patient's blood can suggest a diagnosis. Intervention is an effective technique, but there is controversy due to a lack of data, particularly in lobular artery infarction. We successfully treated one case using thrombus aspiration, and the specimens suggested atherosclerosis as the cause.

Treating Post-stroke Epilepsy in a Patient With Multiple Comorbidities

Stroke is a major cause of seizures and epilepsy in adults. Stroke severity, younger age, hemorrhagic subtype of stroke, and alcohol use have been identified as risk factors for the development of stroke-related epilepsy. Despite being a common complication in stroke survivors, current guidelines do not provide strong recommendations about the optimal treatment of post-stroke seizures. No clear guidance is given about the preferred antiseizure medications (ASMs), primary and secondary prophylaxis, and ASMs withdrawal. The management of older patients is further complicated by the presence of comorbidities, pharmacokinetic alterations, and intake of several medications. We present a case of a 77-year-old man affected by epidermolysis bullosa and diabetes mellitus, who suffered from ischemic stroke and then developed post-stroke seizures. This case shows how complex it is to manage post-stroke seizures in an older patient with multiple comorbidities.

Safety and Efficacy of Apixaban vs Warfarin in Patients With Stage 4 and 5 Chronic Kidney Disease: A Systematic Review

Warfarin has been an anticoagulant of choice in patients with advanced Chronic Kidney Diseases (CKD) at stages 4 and 5 for decades, but with the advent of Novel Oral Anticoagulants (NOACs), there has been a sharp rise in their prescriptions. Among all NOACS, apixaban is the least reliant on kidney function and is a very popular choice for this patient population. However, being utilized extensively, most of the landmark trials evaluating the safety and efficacy of apixaban excluded patients with Creatinine Clearance (CrCl) <25mL/min/1.73 m² or Serum Creatinine (SCr) ≥2.5mg/dL. Its approval for advanced CKD patients came from limited pharmacokinetic data only. We conducted a systematic review comparing the safety and efficacy of apixaban to warfarin in patients with stage 4 and 5 CKD and on dialysis. We queried major research literature databases, including MEDLINE, PubMed, PubMed Central (PMC), Cochrane Central, and ScienceDirect to find relevant articles without any time or language restrictions. After screening and quality checks, we identified 11 studies relevant to our research question, of which nine were retrospective cohort studies, one was a post-hoc analysis of a randomized controlled trial (RCT), and one was an RCT. The included studies had a total of 27,007 patients, with 4,335 patients taking apixaban and 22,672 on warfarin. The results indicate that the overall efficacy of apixaban was equivalent to warfarin for the prevention of stroke, systemic embolization, and recurrent venous thromboembolism, but apixaban showed an equivalent and, in some studies, better safety profile than warfarin concerning the occurrence of bleeding. Apixaban may hence be considered a reasonable alternative to warfarin in patients with Stage 4 or 5 CKD and receiving dialysis. In light of the reviewed articles, we conclude that apixaban has similar efficacy and somewhat superior safety profile to warfarin, with more randomized controlled trials required to add to the evidence.

Adherence to Direct Oral Anticoagulants in Patients With Non-Valvular Atrial Fibrillation: A Cross-National Comparison in Six European Countries (2008-2015)

Aims: To describe and compare the adherence to different direct oral anticoagulants (DOACs) in eight European databases representing six countries. Methods: Longitudinal drug utilization study of new users (≥18 years) of DOACs (dabigatran, rivaroxaban, apixaban) with a diagnosis of non-valvular atrial fibrillation (2008-2015). Adherence was examined by estimating persistence, switching, and discontinuation rates at 12 months. Primary non-adherence was estimated in BIFAP and SIDIAP databases. Results: The highest persistence rate was seen for apixaban in the CPRD database (81%) and the lowest for dabigatran in the Mondriaan database (22%). The switching rate for all DOACs ranged from 2.4 to 13.1% (Mondriaan and EGB databases, respectively). Dabigatran had the highest switching rate from 5.0 to 20.0% (Mondriaan and EGB databases, respectively). The discontinuation rate for all DOACs ranged from 16.0 to 63.9% (CPRD and Bavarian CD databases, respectively). Dabigatran had the highest rate of discontinuers, except in the Bavarian CD and AOK NORDWEST databases, ranging from 23.2 to 64.6% (CPRD and Mondriaan databases, respectively). Combined primary non-adherence for examined DOACs was 11.1% in BIFAP and 14.0% in SIDIAP. There were differences in population coverage and in the type of drug data source among the databases. Conclusion: Despite the differences in the characteristics of the databases and in demographic and baseline characteristics of the included population that could explain some of the observed discrepancies, we can observe a similar pattern throughout the databases. Apixaban was the DOAC with the highest persistence. Dabigatran had the highest proportion of discontinuers and switchers at 12 months in most databases (EMA/2015/27/PH).

An Interesting Case of a Cold Left Arm

Inter-arm variability in blood pressure readings typically signifies arterial disease between the aortic arch and the subclavian artery. The differential diagnosis includes thoracic aortic dissection, atherosclerosis, thoracic outlet syndrome, and subclavian artery stenosis and thrombosis. In patients with prior coronary artery bypass grafting, including the internal mammary artery, several of those conditions can compromise coronary blood flow and lead to myocardial ischemia. Here we discuss a case of left subclavian artery thrombosis, which compromised left internal mammary artery blood flow and led to ischemic ventricular tachycardia.

Use of Anticoagulants in Patients With Non-Valvular Atrial Fibrillation Who Are at Risk of Falls

Atrial fibrillation (AF) is a relatively common clinical entity with significant morbidity and mortality, particularly in the elderly. Stroke is one of the most significant complications of AF, which can be prevented with the use of anticoagulation. Elder population are at an increased risk of falls and the use of anticoagulation in this group can lead to intracranial hemorrhage. Therefore, it is unclear whether patients at high risk of falls should be anticoagulated. This review article discusses the epidemiology of AF and falls in the elder population, and whether the benefit of anticoagulation outweighs the risks in this group.