Excessive sodium: High urinary levels of sodium result in increased levels of calcium. Certain defects in the kidney tubules transport system, which cause imbalances in sodium and phosphate, can lead to high calcium levels in the urine. A diet high in salt can also produce this effect.
Some of the common causes of Decreased cardiac output may include: 1  Mitral regurgitation. 2  Azotemia. 3  Hypotension. Cardiac tamponade.  Restrictive 1  cardiomyopathy. more causes...Â».
Specifically, the resistance comes from the blood vessels and the contraction of the blood vessel walls. Remember that cardiac output is the amount of blood ejected by the heart in one minute. Afterload is one of four processes that make up cardiac output.The other three processes are preload (the pressure of the blood on the heart muscle fibers), contractility (the force of the contraction), and heart rate.To have more cardiac output you have to have lower afterload. Stroke volume is the actual contraction of the muscle fibers that eject the blood from the heart.fterload rises with age and hypertension (increased blood pressure). With age the arteries stiffen due to degeneration; therefore, less contraction of the ventricle occurs and less blood is ejected from the ventricle. Hypertension has a slightly different effect-especially on the left ventricle.