ABSTRACT
In this paper, we propose a new mathematical model of cardiovascular system coupled with a respiratory system to study the effects of COVID-19 on global blood circulation parameters using the lumped parameters model. We use the fourth-order Runge-Kutta method for solving the sets of equations of motion. We validate our model by showing that the simulated flows in pulmonary and aortic valves corroborate, respectively, the results established by Smith et al. [IFAC Proceedings Volumes, 39 (2006) 453-458]. Then we examine the effects of the new coronavirus (covid-19) on the cardiopulmonary system through the impact of the high respiratory frequency and the variation of the alveoli volume. To achieve this aim, we propose a new exponential law for the time varying of the pulmonary resistance. It appears that when the respiratory frequency grows, the delay between the systemic artery flow and the flow in the pulmonary artery diminishes. Therefore, the efficiency of the cardiac pump is reduced. Moreover, our results also show that variations of the alveoli volume cause the increment of the pleural pressure in the vascular cavities that induces an exponential growth of the pulmonary resistance. Furthermore, this growth of the pulmonary resistance provokes the augmentation of pressure in some organs and its reduction in others. We found that patient with covid-19 having a prior history of cardiovascular diseases is exposed to a severe case of inflammation/damage of certain organs than those with no history of cardiovascular disease.
ABSTRACT
Common manifestations of COVID-19 are respiratory and can extend from mild symptoms to severe acute respiratory distress. The severity of the illness can also extend from mild disease to life-threatening acute respiratory distress syndrome (ARDS). SARS-CoV-2 infection can also affect the gastrointestinal tract, liver and pancreatic functions, leading to gastrointestinal symptoms. Moreover, SARS-CoV-2 can cause central and peripheral neurological manifestations, affect the cardiovascular system and promote renal dysfunction. Epidemiological data have indicated that cancer patients are at a higher risk of contracting the SARS-CoV-2 virus. Considering the multitude of clinical symptoms of COVID-19, the objective of the present review was to summarize their pathophysiology in previously healthy patients, as well as in those with comorbidities. The present review summarizes the current, though admittedly fluid knowledge on the pathophysiology and symptoms of COVID-19 infection. Although unclear issues still remain, the present study contributes to a more complete understanding of the disease, and may drive the direction of new research. The recognition of the severity of the clinical symptoms of COVID-19 is crucial for the specific therapeutic management of affected patients.