The decreased co causes the sns to stimulate the beta

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The decreased CO causes the SNS to stimulate the beta cells to increase contractility and HR. But this causes the muscle to overstretch and destroying the muscle contractility even more. Remember the muscle is damage and can not handle the vascular volume so the damaged heart can not get the blood to the organs. The increase of contractility is always good, but consider what if the patient already has an increased HR now further increased HR. Now the organs are being perfused but kidneys are not so much. So the kidneys release ADH causing Na and water to be retained. The retention of volume is what started the scenario. Now the body releases Atrial Natriuretic Factor (this is like what BNP does for the heart) which helps excrete Na and water. This mechanism helps slow down the symptoms of heart failure. All of this leads to words like ventricular hypertrophy, etc. The bottom line is this helps initially, but the heart will decompensate. Heart failure signs and symptoms become increasing acute even though started as a chronic problem.
Heart Failure New York Heart Association Classification Class I – asymptomatic Class II – symptoms with strenuous activity Class III – symptoms with mild activity Class IV – symptoms at rest
Heart Failure Whatever the cause – look at CO and determine how to treat In the early stages, the body has a compensatory mechanism to maintain CO Frank-Starlings Law Activation SNS Activation of the renin-angiotensin system Myocardial hypertrophy
Heart Failure Acute vs Chronic Acute – an abrupt onset (AMI) Chronic – progressive deterioration of the muscle, valves or CHD
Systolic vs Diastolic Failure Systolic failure Ventricle fails to contract adequately to eject enough blood to meet systemic demands Diastolic failure The heart cannot completely relax in diastole; the heart cannot fill completely Can have both types of failure
Left-Sided vs Right-Failure Left Sided Ventricle fails CHD and HTN usual cause Pulmonary involvement along with decease CO Pulmonary congestion Left sided failure can lead to right failure Signs and Symptoms for this? Right Sided Caused by conditions that restrict blood flow to the lung (lung disease) Deceased CO What is happening in the heart?
Low-Output vs High-Output Failure Low-Output Heart failure caused by CHD, HTN, cardiomyopathy or other primary cardiac disorders The pump cannot get enough blood to the other organs (this is right or left failure as described in the previous slides) High-Output These are patients in a hyper-metabolic state Infection, pregnancy, anemia, hyperthyroidism The heart cannot meet the high demands needed by these disease states
Manifestations What are the manifestations?

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