Congestive Heart Failure

Samara Leamon

(S0176025)

Cardiorespiratory Physiology & Measurement

BMSC12006

Written Assessment

Effects of Congestive Heart Failure on the Cardiovascular & Respiratory Systems

Stated by the American Heart Association (2011), ‘the purpose of the heart is to pump blood to the body in order to nourish it’. Congestive heart failure (CHF) occurs when the muscles of the heart are too weak to pump blood around the body as efficiently as it should. This can the cause symptoms such as fatigue or fluid build up in the lungs and other body tissues where signs of being short of breath or swelling in the legs may occur (Heart Foundation 2014). The following will describe the interrelationship between the cardiovascular and respiratory systems in CHF, examine practical techniques and discuss how changes can be typically assessed while further discussion will include the implications of the relationship between both systems.

Clinically, CHF can be categorized as systolic heart failure which is defined as the inability of the heart to generate an adequate cardiac output to perfuse vital tissues (McCance, Huether, Brashers & Rote 2010, p. 1190). Cardiac output depends on the heart rate and stroke volume, where stroke volume is determined by three major factors including contractility, pre-load and after-load (Figueroa & Peters 2006). Contractility is reduced by diseases that interfere with myocyte activity and mediate the process of ventricular remodeling. This results in hypertrophy and dilation of the myocardium and over time causes progressive myocyte contractile dysfunction. When contractility is decreased, stroke volume falls which causes an increase in pre-load (McCance, Huether, Brashers & Rote 2010, p. 1190). Increased after-load most commonly is a result of increased peripheral vascular resistance (PVR). With increased PVR, there is resistance to ventricular emptying and more workload for the left ventricle, which responds with hypertrophy of the myocardium....