Week 5

Question 1

What is heart failure?

Answer 1

Clinical syndrome, impaired inability to fit the heart with blood or pump blood.

Question 2

What is HF caused by?

Answer 2

Ischemic heart disease/CAD, chronic hypertension, complications of MI. Htn and CAD major factors.

Question 3

What is HF characterized by?

Answer 3

Ventricular dysfunction, reduced exercise tolerance, diminished quality of life, shorter life expectancy,

Question 4

What are the mechanisms of cardiac output?

Answer 4

Preload, Afterload, Myocardiac contractibility, HR, metabolic state of person.

Question 5

What is HF with ejection fraction/ systolic HF?

Answer 5

Inability to pump blood effectively due to left ventricle loses its ability to generate enough pressure to eject blood into aorta.

Question 6

What is the ejection fraction?

Answer 6

% of total amount of end-diastolic blood volume ejected during each systole.

Question 7

What is a normal EF?

Answer 7

Greater than 55% of ventricular volume.

Question 8

What is HF with preserved ejection fraction/diastolic HF?

Answer 8

Inability of the ventricles to relax enough so they can fill it with blood during diastole.

Question 9

What does diastolic HF result in?

Answer 9

decreased stroke volume and CO that leads to engorgement of pulmonary and systematic vascular systems.

Question 10

What is LS HF?

Answer 10

Results from altered function of the left ventricle, blood is not being pumped out of the aorta into circulation. Blood backs up into pulmonary veins, increased pressure-flow leaks into the pulmonary capillary bed into the interstitium and then the alveoli.

Question 11

What are the S and S of LF HF?

Answer 11

Paroxysmal nocturnal dyspnea
Elevated pulmonary capillary wedge
Pulmonary congestion
Coughing, crackles, wheezing, tachypnea
Restlessness and agitation
Confusion and fatigue
Orthopnea, tachycardia
Increased RR, HR, BP
Decreased PaCO2

Question 12

What is RS HF?

Answer 12

Engorgement of the pulmonary vascular system, caused by LS HF. Puts an increased amount of pressure on the small vessels in the lungs and increases resistance in the small airway. Backwards flow of the RA and venous circulation causes enlargement of the RS and failure.

Question 13

What does pulmonary edema cause?

Answer 13

Inhibits O2 and CO2 exchange at alveolar capillary interface. Increased pulmonary capillary exchange hydrostatic pressure causes fluid to move up from the vascular space to pulmonary interstitial space.

Question 14

What does failure of the lymphatic flow cause?

Answer 14

Worsens HF and moves fluid into the interstital space and into alveoli.

Question 15

What are the S and S of RS HF?

Answer 15

Fatigue
Cor pulmonale- dilation of the RV and hypertrophy
Increased peripheral venous pressure
Ascites
Enlarged spleen and liver with peripheral edema
Distended jugular veins
Anorexia, GI distress, weight gain.

Question 16

What are some chronic HF manifestations?

Answer 16

Fatigue, secondary to decreased CO, impaired circulation and decreased oxygenation to tissues.
Dysponea secondary to increased pulmonary pressure.
Orthopnea
Paroxysmal nocturnal dyspnoea
Tachycardia
Angina
Weight changes

Question 17

How does the heart compensate for HF by dialating the ventricles?

Answer 17

Muscles fibres of hte LV stretch out and increase their contractile force to increase CO and maintain atrial BP to perfuse the body. The overstreched fibres loose their elasticity and can’t contract and decreases the CO.

Question 18

How does the body compensate by hypertrophy of the ventricles for HF?

Answer 18

Increased muscle mass and cardiac wall thrombus in response to a heart that is overworked and overstrained. Once the wall is less thick due to muscle tissue mass increases so CO and restore perfusion.

Question 19

How does the body compensate by activating the SNS in HF?

Answer 19

CO and SV decrease will allow the activation and release of mins and glucs. This increases HR, contractilability of the myocardium and peripheral vascular constriction, but it requires more O2 causes stress.

Question 20

What are other homeostatic mechanisms involved in the compensation of HF?

Answer 20

Adrenal cortex and kidney RAAS, posterior pituitary ADG. Neurohormonal response may overload heart.

Question 21

What do naturiuretic peptides and hormones encourage the body to do?

Answer 21

Encourages vasodilation, diuresis, and prevents cardiac hypertrophy. This decreases afterload and preload.

Question 22

What are the 2 peptides produced by the heart muscle?

Answer 22

Atrial natriuretic peptide (atrium)

Brain natriuretic peptide (ventricles)

Question 23

What are the renal and CV actions of natriuretic peptides?

Answer 23

Naturesis
Diuresis
Improve glomerular filtration rate and filtration fraction
Inhibit renin release and decrease circulating angiostensin 2 and aldostrone
Systematic vasodilation
Arterial hypotension
Decreased venous pressure and pulmonary capillary wedge pressure.

Question 24

How is chronic HF managed?

Answer 24

ID type and causes, treat causes.
Correct Na and water retention
Decrease amount of work by the heart and improve myocardial contractibility
Control factors that could precipitate it
Improve symptoms and decrease side effects
Prevent morbidity and prolong life.