What is meant by the term ejection fraction? What will be an ...

[kamilo84]

What is meant by the term ejection fraction?
 
  What will be an ideal response?

Question 2

In pacing, rate modulation refers to _____.
 
  a. the ability of a pacemaker to recognize and respond to intrinsic electrical activity
  b. the minimum level of electrical current needed to consistently depolarize the myocardium
  c. the ability of a pacemaker to increase the pacing rate in response to physical activity or metabolic demand
  d. a pacing lead with a single electrical pole at the distal tip of the pacing lead through which the stimulating pulse is delivered.

[sarah_brady415]

Answer to Question 1

Ejection fraction is the percentage of blood pumped out of a heart chamber with each contraction. Each ventricle holds about 150 mL when it is full; they normally eject only about half this volume (70 to 80 mL) with each contraction.

Answer to Question 2

C
Rate modulation refers to a pacemaker's ability to adapt its rate to meet the body's needs caused by increased physical activity and then increase or decrease the pacing rate accordingly. A pacemaker's rate modulation capability may also be referred to as rate responsiveness or rate adaptation.