Believe it or not, heart failure is somewhat difficult to define. It is best thought of as a condition in which the heart cannot meet the demands of the peripheral circulation in all situations.
How is it diagnosed?
No single test is diagnostic for congestive heart failure. The diagnosis is usually not difficult to make and is based on an assessment of the history, physical examination, and chest x-ray. It is important to use these data to decide if the patient has left ventricular failure, right ventricular failure, or a combination of both, since the causes and treatments differ. Occasionally, it is necessary to call on more sophisticated testing to make the diagnosis.
What are the four determinants of cardiac output?
Afterload, preload, heart rate, and myocardial contractility.
Which of these is abnormal in heart failure?
Actually, all four are abnormal. In most cases of heart failure, the initial event is a decline in myocardial contractility from any one of a number of causes.
What happens to afterload?
In response to decreased peripheral perfusion caused by a decline in cardiac output, systemic vascular resistance rises. Although there are several mechanisms for this, the most important are a rise in circulating catecholamines and activation of the sympathetic nervous system. Initially, this rise in afterload helps to maintain organ perfusion. When .more advanced, it can become counterproductive and lead to a further reduction in cardiac output.
What is heart failure? Photo Gallery
Maybe You Like Them Too
- DR Karen Sherman Lead Researcher at The Seattle Group Health Center
- To Start Winning The Battle of The Bulge You Need to Be Able to Separate Fact From Fallacy
- Are There any Foods That can Help Reduce Stress?
- I Pack Lunch to Save Money But am Getting Sick of The Same Old Same Old Any Tips to Spice Things Up?
- Shopping at a Local Farmers Market is One of The Best Ways to Improve Your Diet and Your Overall Health