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In an attempt to improve the thermoelectric (TE) properties of conducting polymers, polypyrrole/metal hydroxide composites were prepared. Oxidative polymerization technique was used to prepare polypyrrole (PPy), while sol gel method was used to produce the metal hydroxides of Ni(II), Co(II), Sr(II), Si(IV) and Zn (II). Typically, an in-situ approach was used to polymerize pyrrole monomer on the surface of the resultant hydroxides. The structural and surface properties of the prepared composites were analyzed by different techniques. The prepared composites were compacted into pellets to investigate their thermoelectric properties. The presence of metal hydroxides with polypyrrole were found to significantly enhance the power factors and the figure of merits values. At room temperature the first factor increased from 0.07 µW/m K2 for the neat PPy to approximately 0.32 µW/m K2 for the polypyrrole/metal hydroxide composites mainly of Co, while the second one increased from 0.05 × 10−3 to 0.36 × 10−3. The TE properties of polypyrrole/metal hydroxide composites of Ni and Si were also enhanced due to the significant reduction in their thermal conductivity. The findings from this study may potentially serve as a valuable resource for the advancement of future thermoelectric materials and devices. [ABSTRACT FROM AUTHOR]

Left ventricular thrombi form due to the presence of Virchow's triad in patients with left ventricular systolic dysfunction. This complication increases the incidence of systemic embolization, hence anticoagulation is recommended to decrease this risk. Up to the present time, vitamin K antagonists are recommended by all societal guidelines for patients with left ventricular thrombi. Recently, several studies have investigated the role of different anticoagulants and yielded promising outcomes. This opinion article focuses on the evidence supporting vitamin K antagonists and direct oral anticoagulants in patients with left ventricular thrombi. [ABSTRACT FROM AUTHOR]

Oral vitamin K antagonists (VKAs), warfarin, have been in routine clinical use for almost 70 years for various cardiovascular conditions. Direct-Acting Oral Anticoagulants (DOACs) have emerged as competitive alternatives for VKAs to prevent stroke in patients with non-valvular atrial fibrillation (AF) and have become the preferred choice in several clinical indications for anticoagulation. Recent guidelines have limited the use of DOACs to patients with non-valvular AF to reduce the risk of cardioembolic complications and to treat venous thromboembolism (VTE). Although emerging evidence is suggestive of its high efficacy, there was a lack of data to support DOACs safety profile in patients with mechanical valve prosthesis, intracardiac thrombi, or other conditions such as cardiac device implantation or catheter ablation. Therefore, several clinical trials have been conducted to assess the beneficial effects of using DOACs, instead of VKAs, for various non-guideline-approved indications. This review aimed to discuss the current guideline-approved indications for DOACs, advantages, and limitations of DOACs use in various clinical indications highlighting the potential emerging indications and remaining challenges for DOACs use. Several considerations are in favour of switching from warfarin to DOACs including superior efficacy, better adverse effect profile, fewer drug-drug interactions, and they do not require frequent international normalized ratio (INR) monitoring. Large randomized controlled trials are required to determine the safety and efficacy of their use in various clinical indications. [ABSTRACT FROM AUTHOR]

Background: Despite the marked improvement in the aortic dissection repair techniques, residual dissected aorta with a patent false lumen remains an issue. So, the aim of our study is to observe the effect of inserting the Thoraflex Hybrid Graft on the aortic diameters in patients with type A aortic dissection involving the arch and descending aorta. Patients with type I aortic dissection who had aortic dissection repair using the Thoraflex Hybrid Graft in University Hospitals Birmingham were studied. Radiological assessment with computed tomography of the aorta was done at the level of the diaphragm to measure the true lumen, false lumen and total aortic diameters. Significance of change of diameters at early post-operative as compared to the pre-operative period was analysed. Results: Eight cases were done in the acute setting, while 14 cases were done in the chronic setting. The ratio of true lumen to the total aortic diameter has significantly increased in the follow-up period as compared to the pre-operative period (P = 0.031). Whereas false lumen to total aortic diameter ratio has significantly decreased (P = 0.024). Subgroup analysis revealed that these changes were not significantly altered by whether the dissection was acute or chronic. Conclusions: The Thoraflex Hybrid Graft will induce positive aortic remodelling with expansion of true lumen and will diminish the false lumen. But we could not find a significant difference between acute or chronic cases due to small sample size. [ABSTRACT FROM AUTHOR]

Background: Subaortic obstruction by a membrane or systolic anterior motion of the mitral valve leaflets is usually suspected in young patients, especially if the anatomy of the aortic valve is not clearly stenotic and unexplained left ventricular hypertrophy exists in the context of high transaortic gradients. Main body: In certain circumstances, some patients show both aortic and subaortic stenotic lesions of variable severity. Doppler echocardiography can help in grading severity in the case of single-level obstruction but not in patients with multilevel obstruction where the continuity equation is of no value. Three-dimensional (3D) echocardiography allows "en-face" visualization of each level of the aortic valve and subaortic tract; in addition, direct planimetry of the areas can be done using multiplanar reformatting. Conclusions: Accordingly, 3D echocardiography plays a crucial role in the assessment in patients with multilevel left ventricular outflow tract obstruction as it can accurately delineate the location and size, and severity of the stenosis. [ABSTRACT FROM AUTHOR]

Background: Direct oral anticoagulants (DOACs) have a well-established role in the treatment of deep vein thrombosis and pulmonary embolism and in the reduction of thromboembolism in nonvalvular atrial fibrillation. However, limited evidence supports their role in patients with left ventricular thrombi. Methods: The PubMed, EMBASE, and Cochrane databases were searched for relevant articles published from inception to 1 August 2020. We included studies evaluating the effect of DOACs versus vitamin K antagonists (VKAs) in patients with left ventricular thrombi. The primary outcome was thrombus resolution, and the secondary outcomes were major bleeding and stroke or systemic embolization (SSE). Results: Five retrospective observational studies were included, with a total of 857 patients. VKAs and DOACs had a similar rate of thrombus resolution (odds ratio [OR] 0.97; 95% confidence interval [CI] 0.57–1.65; p = 0.90). Our analysis also demonstrated a similar rate of major bleeding (OR 0.62; 95% CI 0.27–1.44; p = 0.27) and SSE (OR 1.86; 95% CI 0.99–3.50; p = 0.05) between the two treatment groups. Conclusion: In patients with left ventricular thrombi, DOACs and VKAs are associated with similar rates of thrombus resolution, major bleeding, and SSE. [ABSTRACT FROM AUTHOR]

Background: Novel coronavirus disease 2019 (COVID-19) is known to lead not only to severe acute respiratory syndrome, but also can result in thromboembolic events in both the venous and the arterial circulation by inducing coagulation disorders. The potential causes of coagulopathy are inflammation, platelet activation, endothelial dysfunction, and stasis. The thrombotic events including pulmonary embolism, deep venous thrombosis as well as intracatheter thrombosis are more likely to develop in patients infected with severe form of SARS-CoV-2 who are admitted to ICU. Furthermore, these events contribute to multi-organ failure. Case presentation: Herein, we report a case of an immunocompromised COVID-19 elderly patient with acute lymphocytic leukemia who developed myocardial infarction with ST elevation in the setting of acute pulmonary thromboembolism in the presence of zero platelet count. Despite successful urgent coronary revascularization and platelet transfusion, the patient eventually died after failed resuscitation efforts. Conclusion: Patients with COVID-19 infection are at a greater risk of developing cardiovascular complications, but their appropriate management can decrease the risk of fatal events. Coronary thrombosis associated with pulmonary thromboembolism in the setting of thrombocytopenia is a rare and a complex to manage condition. Significance of single antiplatelet agent in STEMI with thrombocytopenia merits further studies. According to expert opinions and literature reviews, we must avoid dual antiplatelet therapy in these patients and keep platelet transfusion as a standard therapy to avoid drastic bleeding complications. [ABSTRACT FROM AUTHOR]

Many recent studies have investigated the role of either Chloroquine (CQ) or Hydroxychloroquine (HCQ) alone or in combination with azithromycin (AZM) in the management of the emerging coronavirus. This systematic review and meta-analysis of either published or preprint observational studies or randomized control trials (RCT) aimed to assess mortality rate, duration of hospital stay, need for mechanical ventilation (MV), virologic cure rate (VQR), time to a negative viral polymerase chain reaction (PCR), radiological progression, experiencing drug side effects, and clinical worsening. A search of the online database through June 2020 was performed and examined the reference lists of pertinent articles for in-vivo studies only. Pooled relative risks (RRs), standard mean differences of 95% confidence intervals (CIs) were calculated with the random-effects model. Mortality was not different between the standard care (SC) and HCQ groups (RR = 0.99, 95% CI 0.61–1.59, I2 = 82%), meta-regression analysis proved that mortality was significantly different across the studies from different countries. However, mortality among the HCQ + AZM was significantly higher than among the SC (RR = 1.8, 95% CI 1.19–2.27, I2 = 70%). The duration of hospital stay in days was shorter in the SC in comparison with the HCQ group (standard mean difference = 0.57, 95% CI 0.20–0.94, I2 = 92%), or the HCQ + AZM (standard mean difference = 0.77, 95% CI 0.46–1.08, I2 = 81). Overall VQR, and that at days 4, 10, and 14 among patients exposed to HCQ did not differ significantly from the SC [(RR = 0.92, 95% CI 0.69–1.23, I2 = 67%), (RR = 1.11, 95% CI 0.26–4.69, I2 = 85%), (RR = 1.21, 95% CI 0.70–2.01, I2 = 95%), and (RR = 0.98, 95% CI 0.76–1.27, I2 = 85%)] respectively. Exposure to HCQ + AZM did not improve the VQR as well (RR = 3.23, 95% CI 0.70–14.97, I2 = 58%). The need for MV was not significantly different between the SC and HCQ (RR = 1.5, 95% CI 0.78–2.89, I2 = 81%), or HCQ + AZM (RR = 1.27, 95% CI 0.7–2.13, I2 = 88%). Side effects were more reported in the HCQ group than in the SC (RR = 3.14, 95% CI 1.58–6.24, I2 = 0). Radiological improvement and clinical worsening were not statistically different between HCQ and SC [(RR = 1.11, 95% CI 0.74–1.65, I2 = 45%) and (RR = 1.28, 95% CI 0.33–4.99), I2 = 54%] respectively. Despite the scarcity of published data of good quality, the effectiveness and safety of either HCQ alone or in combination with AZM in treating COVID-19 cannot be assured. Future high-quality RCTs need to be carried out. PROSPERO registration: CRD42020192084. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) affects millions of people worldwide and can remain undiagnosed for years. It is a major cause of cerebrovascular stroke (CVS); hence, early detection is extremely important in order to decrease the risk of CVS. We conducted a retrospective observational study looking into the prevalence of silent AF in 3299 patients admitted from January 2014 to December 2017 in a tertiary care stroke specialized center. Ischemic CVS was confirmed either by using multislice computed tomography (MSCT) or magnetic resonance imaging (MRI) of the brain. AF was diagnosed by electrocardiography (ECG) at the time of admission or during the hospital stay. Patients with a history of AF were excluded from the study. Results: Of the 3299 patients admitted by acute ischemic CVS, 707 (21.43%) had a history of AF and thus were excluded from the study. Of the remaining 2592 patients eligible for the study, 1666 (64.27%) were males with a mean age of 56.06 years (± 16.01). A total of 2313 (89.24%) patients remained in sinus rhythm throughout the hospital stay, 211 (8.14%) patients were in AF on admission, and 68 (2.62 %) patients developed AF during their hospital stay. The total number of newly diagnosed patients with AF was 279 (10.76%). Conclusion: The prevalence of de novo atrial fibrillation in patients presented with acute cerebrovascular stroke is high. The implementation of good screening programs can significantly reduce the risk of disabilities and morbidities. [ABSTRACT FROM AUTHOR]

Background: Cardiac metastases in hepatocellular carcinoma patients are infrequently encountered and usually associated with a very poor prognosis. Case presentation: Hereby, we report a case of an acute pulmonary embolism (PE) on top of HCC with direct cardiac invasion to the right atrium (RA) through the inferior vena cava with another metastasis to the right ventricular apex in the form of highly mobile cauliflower mass protruding through the tricuspid valve into RA and nearly obliterating right ventricular outflow tract in a multi-centric hepatocellular carcinoma patient. Conclusion: Acute dyspnea in a patient with a long history of hepatitis C virus infection raises the suspicion of acute PE due to either hypercoagulable state induced by malignancy or by cardiac extension of the tumor which usually carries high mortality rates. To the best of our knowledge, this case is the first case in the literature to show cardiac metastases in HCC with two different pathological mechanisms. [ABSTRACT FROM AUTHOR]

A 17-year-old male patient with Gaucher disease was presented to our institution complaining of rapid irregular palpitations. Echocardiography showed the presence of critical aortic stenosis due to Gaucher disease. [ABSTRACT FROM AUTHOR]

Although very rarely encountered nowadays, bilharziasis should still be considered as one of the main causes of pulmonary artery aneurysms (PAA) and core-pulmonale in endemic areas. The ideal treatment of PAA remains uncertain because there is no clear consensus about the best therapeutic approach, due to limited experience because of the rarity of the disease. Still the management of pulmonary artery thrombus is only through proper anticoagulation and follow-up with a very limited role for surgery. [ABSTRACT FROM AUTHOR]

Background: Endomyocardial fibrosis (EMF) is a form of restrictive cardiomyopathy that is diagnosed mainly in children and young adults and is geographically found in Africa, Latin America, and Asia. It is a condition with high morbidity and mortality, unknown etiology, and no definitive treatment. Although its main clinical presentation is congestive heart failure with or without related supraventricular arrhythmia like atrial fibrillation, it very rarely presents with ventricular arrhythmias and tachycardias (VA, VT). Case presentation: We report a case of right ventricular (RV) EMF presented with recurrent attacks of hemodynamically unstable VT that required direct current (DC) cardioversion. The diagnosis was suspected by transthoracic echocardiography (TTE) and established by cardiac magnetic resonance (CMR). The patient underwent implantable cardioverter–defibrillator (ICD) implantation for secondary prevention of VT, and he was discharged safely on antiarrhythmic drugs with regular follow-up visits. Conclusion: EMF presenting with VT are quite rare and to the best of our knowledge, our case is the fourth case in the literature to report VT as a clinical presentation of EMF. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is considered the third-leading cause of cancer-related mortality worldwide. Most cases of HCC are usually associated with liver cirrhosis due to various causes such as alcohol or more commonly viral hepatitis. Usually, patients remain asymptomatic for a long time, and symptoms are usually related to the cirrhosis itself or secondary to tumor extension. Intra-cardiac involvement with HCC rarely develops with a very poor prognosis. The occurrence and recurrence of HCC in cirrhotic patients treated with direct-acting antiviral (DAA) therapy (sofosbuvir) have been discussed in a few trials so far with no valid answer. Case presentation: We are reporting a case of recurrent HCC with an accidentally discovered direct right atrial extension with tumor thrombus through the inferior vena cava (IVC) in a cirrhotic patient previously treated with DAA. Unfortunately, due to his critical general condition, he died within days. Conclusion: Cardiac involvement in HCC rarely occurs and usually develops in advanced stages of HCC with very poor reported prognosis. Data regarding the relation between DAA and HCC development is controversial. [ABSTRACT FROM AUTHOR]