Video: The Great Migration: Definition & Causes. The economic conditions of World War I led to a massive movement of African Americans from the South to the North, known as the Great Migration. Examine the causes and effects of this phenomenon.
Physicians may want to look closer at WBC levels when obtaining the tests for other reasons, Manson notes. However, infections can cause a high white blood cell count that may make it appear that a patient is at high risk for heart disease when she is not. Therefore, routinely giving everyone the test to screen for heart disease is premature. More research needs to be done..
Catecholamines a great effect over the cardiovascular system affecting the activity of the heart and blood vessels. The catecholamines increases all four effects of heart activity. Increase of the inotropic effect causes contractility of the cardiac muscle increasing the cardiac output by increasing the stroke volume.