Drawing Parallels between SARS, MERS, and COVID-19: A Comparative Overview of Epidemiology, Pathogenesis, and Pathological Features.

Background: Since November 2019, when the novel coronavirus arose in Wuhan City, over 188 million people worldwide have been infected with COVID-19. It is the third coronavirus outbreak in the twenty-first century. Until now, practically all coronavirus epidemics have occurred due to zoonotic spread from an animal or transitional host or through the consumption of their products. Coronaviruses can infect humans and cause severe illness and even death. Material and Methods: This review was designed to help us recognize and harmonize the similarities and differences between these three coronaviridae family members. Result: Measures aimed at containing the epidemic should be emphasized in this circumstance. Prioritizing and planning these activities require an understanding of the particulars of these three viruses. Given the pandemic's enormous death toll and rapid spread, we should be cognizant of the parallels and differences between these three viruses. Additionally, this pandemic warns us to be cautious against the possibility of a future pandemic. Conclusion: We highlight the fundamental characteristics of coronaviruses that are critical for recognizing coronavirus epidemiology, pathogenesis, and pathological features that reveal numerous significant pathological attributes and evolutionary patterns in the viral genome that aid in better understanding and anticipating future epidemics.

Evolving Indications of Transcatheter Aortic Valve Replacement Compared to Surgical Valve Replacement: A Review of the Current Literature.

Patients with severe symptomatic aortic stenosis (AS) are categorized into high risk, intermediate risk, and low risk. The identification of risk status is done using the Society of Thoracic Surgeons mortality score. Various factors are considered such as clinical symptoms, ejection fraction, age, left ventricle measurements, severity of AS, associated comorbid factors, and any other associated cardiac diseases. Surgery is still a standard practice in many countries. However, it has its own complications, especially in high-risk patients. Transcatheter intervention is getting precipitous recognition as an alternative mode of treatment in selected cases to mitigate complication rates and improve quality of life. In this article, transcatheter aortic valve replacement and surgical aortic valve replacement are compared in patients with different surgical risks. The impact of the cost of the procedure and quality of life are of paramount importance in choosing the type of intervention. Structural valve degeneration is an independent risk factor affecting patient outcomes. Modifications in valve designs are being constantly implemented as well. The standard analytical methods are in accordance with randomized clinical trials to determine the efficacy and outcome of procedures. Primary and secondary endpoints were considered to evaluate the data. The results were tabulated to derive statistical significance of the studies. In high-risk surgical patients, transcatheter intervention has been proven as the procedure of choice for valve replacement. However, intermediate-risk and low-risk categories need further studies.