Comparing novel oral anticoagulants to vitamin k antagonists in patients with hypertrophic cardiomyopathy and atrial fibrillation: an updated systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is a common occurrence in Hypertrophic cardiomyopathy (HCM), reported in approximately one third of cases. The 2011 ACC guidelines for management of HCM with concomitant AF recommend use of Vitamin K Antagonists (VKA); however, new research and randomized clinical trials present data which favor the use of Novel Oral Anticoagulants (NOAC) over VKA to prevent serious outcomes.

Purpose

We aim to identify the difference between NOAC and VKA in preventing ischemic stroke and thromboembolism, and calculate the rate of intracranial hemorrhage, major bleeding and all cause mortality in both treatment groups.

Methods

We conducted a systematic review and meta-analysis with the aim to answer the following clinical question: What is the efficacy of NOACs vs VKA in preventing thromboembolism and what are the associated risks with each group? We followed PRISMA guidelines. Scientific databases (PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Epistemonikos) were searched using relevant medical subject headings and keywords to retrieve studies published through September 24, 2020. Inclusion criteria were patients over 18 years old, use of NOACs and VKA in atrial fibrillation and HCM. Studies with patients who had catheter ablative therapy were excluded. After an exhaustive review, a total of 6 studies including 2 Randomized Control Trials (RCTs) and 4 retrospective cohort studies were analyzed using RevMan 5.4 to analyze event rate, hazard ratio and 95% confidence interval for ischemic stroke/thromboembolism, all-cause mortality, major bleeding and intracranial hemorrhage. One study was later excluded due to insufficient data. Heterogeneity was assessed by using the I2 statistic.

Results

A total of 9,168 patients [NOAC 5158 and VKA 4010] were pooled. Meta-analysis showed the NOAC treatment group had a significant improvement in preventing the primary outcome ischemic stroke/thromboembolism [HR 0.41; 95% CI 0.26 -0.63, p = <0.001], as well as secondary outcomes; all cause mortality [HR 0.37, 95% CI 0.19 - 0.73, p = 0.004, p = 0.004], Intracranial hemorrhage [HR 0.43; 95% CI, 0.11 - 1.65, p = 0.22], and Major Bleeding [HR 0.56; CI 95% 0.34 - 0.93, p = 0.02].

Conclusion

Anticoagulation of patients with HCM and AF using NOACs was associated with lower risk of ischemic stroke and thromboembolic events in the NOACs group. There was also a statistically significant reduction of all-cause mortality and major bleeding among patients with AF and HCM who had received NOACs as compared to VKA. There was a notable reduction of ICH in the NOACs group as well. Further clinical trials are needed to further assess the long term benefits of using NOACs in these patients.

The unusual traumatic locked young knee

Locked knee is an orthopaedic condition requiring urgent treatment. Although the condition can be diagnosed via history, physical examination and imaging studies, the cause of the mechanical obstruction may only be apparent during arthroscopic examination of the knee joint. It is known that imaging plays a role in evaluating the integrity of intra-articular structures, however in some atypical cases, imaging cannot identify the definitive cause of locked knee. Here we report on two cases of locked knee, due to uncommon conditions which were unobservable via normal imaging studies.

Pulled/nursemaid's elbow

Nursemaid's elbow is a radial head subluxation caused by axial traction on the extended arm while the forearm is pronated, allowing for slippage of the radial head. A 2-year-old boy presented with pain, swelling and reduced range of movement of the right elbow for 4 days. The mother noted that the child was moving the right upper limb less often and there was tenderness over the right elbow. X-ray of the right elbow showed subluxation of the elbow joint with no obvious fracture. A trial of conservative management was decided upon and the patient was placed on a right elbow backslab with the right forearm in a supine position. On follow-up, there was no swelling, tenderness or neurological deficit noted. A repeate x-ray revealed normal findings.

Reduction of oxidative-nitrosative stress underlies anticataract effect of topically applied tocotrienol in streptozotocin-induced diabetic rats

Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels.

Chronic heel pain: It could be tuberculosis

INTRODUCTION

Heel pain is a common presentation at a primary care setting. The majority of these cases are benign and self limiting in nature. Common differential diagnoses include plantar fasciitis and peroneal muscle sprains. However, certain conditions-if undetected early-may cause significant morbidity to the patient. A high index of suspicion and early referral for further investigations are needed to prevent long-term morbidities.

METHODS

A clinical review of a patient with chronic left heel pain was performed. Blood parameters and imaging investigations indicated chronic infection of the calcaneum. Histopathological examination was highly suggestive of tuberculosis.

RESULT

The patient responded well to antituberculous therapy. She was pain free and showed no signs of recurrence at final follow-up.

CONCLUSION

Here, we report a case of chronic heel pain, which was later diagnosed as tuberculosis of the calcaneum and successfully treated with antituberculous therapy.

Salmonella spondylodiscitis of the thoracic vertebrae mimicking spine tuberculosis

Extraintestinal Salmonella infection involving the thoracic spine is very rare. It commonly presents with non-specific chronic back pain and can occur with no gastrointestinal manifestation. Blood test results and imaging findings are often indistinguishable from more common chronic spine infections such as spine tuberculosis. Culture studies remain the key to establishing a definitive diagnosis and subsequently successful treatment. We report a case in which a patient presented with symptoms and signs suggestive of spine tuberculosis, yet the culture examination revealed otherwise.

Medication noncompliance--a thriving problem

A study was conducted among out-patients attending the Melaka Tengah Health Clinic to determine their compliance status towards antihypertensive, antidiabetic and antiasthmatic drugs. A total of 585 patients were enrolled in this study. Assessment of compliance was carried out using pill-counting and house-to-house interviews 14 days from the date of medication dispensed at the counter. The noncompliance rate among the 464 successfully interviewed patients was 56%. The mean noncompliance percentage was 78.0 +/- 43.1% (range: -10.0-314.3%). Among the four variables of compliance studied, race was not seen as a determinant of compliance. The older age group and those taking two or more drugs were statistically significant to be a noncomplier. Females were highly likely not to comply with drug therapy. Patients who conform to their refill dates were not really drug compliers. Forgetting to take their drugs and inability to read instructions on drug labels were the main reasons given. Underdosing was more common than overdosing, with an estimated cost of RM20,261.00 of unused medications per year.

Liver tissue schistosomiasis mansoni vaccine, as a third generation livestock immunogenes

Liver tissue of Schistosoma mansoni-infected hamsters has been tried to immunize white mice against Schistosoma mansoni infection. A saline suspension of liver tissue of infected hamsters was prepared and given subcutaneously in the ventral aspect of the abdominal wall to the right of the umbilicus. The present study proved that the used vaccine has a protective role in reducing the morbidity and mortality of the disease.

Effect of aprotinin on Schistosoma mansoni miracidial penetration into biomphalaria Alexandrina

The effect of aprotinin on Schistosoma mansoni miracidial penetration process, by its direct topical application on Biomphalaria alexandrina snails, was studied The snails were exposed to S. mansoni miracidial suspension which was mixed with aprotinin at concentrations ranging from 0.02 to 20 Kallikrein inactivator units (KIU)/ml of applied solution. Results showed that aprotinin had marked inhibitory effect on miracidial penetration of the snails. The concentration that resulted in 50% inhibition of the miracidial penetration into B. alexandrina snails (LD50) was 2.4 KIU/ml while (LD96) was 20 KIU/ml of the applied solution. Thus, aprotinin may be one of the important methods in the control of schistosomiasis.

Treating one's own ailments

A small survey in Peninsular Malaysia indicates a marked tendency among the general population to treat minor ailments by self-medication with over-the-counter drugs and/or traditional medicines. The use of over-the-counter drugs appears to be favoured for skin conditions, general health care, aches and pains, and problems affecting the eyes, ears, mouth, gastrointestinal tract and respiratory tract. A doctor is usually consulted if self-medication fails.