Provide a 6 pages analysis while answering the following question: Issues of Cardiovascular System. Prepare this assignment according to the guidelines found in the APA Style Guide. An abstract is required. The SL valves for the left ventricle opens when the ventricular pressure passes the aortic pressure (80mmHg) while the SL valve for the right ventricle opens when the ventricular pressure passes the pressure in the pulmonary trunk, that is, 20mmHg. The relaxation period lasts about 0.4 seconds but shortens when the heart beats faster. It occurs when blood flows towards the heart from the aorta and pulmonary trunk as the SL valves close at a pressure of about 100mmHg due to backflow to prevent blood from re-entering the ventricles (Tortora & Derrickson, 2009).

Heart sounds can be heard due to the turbulent flow of blood after the heart valves close. Although there are four heart sounds, only S1 and S2 are loud enough to be heard from a healthy heart. S1 (lub) results from the closure of the AV valves when the ventricular systole begins while S2 (dup) results from the closure of SL valves at the start of ventricular diastole. S1 and S2 are best detected from chest locations slightly away from the valves because the sound waves are carried by blood flow through the arteries. S3 and S4 are not loud enough to be heard by the naked ear and so a stethoscope comes in handy. S3 is due to blood turbulence during ventricular filling while S4 is a result of blood turbulence during atrial systole (Tortora & Derrickson, 2009).

Systematic vascular resistance (SVR) refers to the sum total of the vascular resistances of all systemic blood vessels. Vascular resistance, the opposition of blood flow due to friction between the blood and the tunica interna of the walls of the blood vessels, is controlled by three main factors namely. lumen diameter, blood viscosity and blood vessel length. The smaller the lumen diameter, the greater the resistance to blood flow (vasodilation widens the lumen while vasoconstriction narrows it). Resistance to blood flow increases with blood viscosity.&nbsp.