Card Set Information
Matching stimulation with mechanical work
What is the fundamental contracting unit in the heart?
What is the function of intercalated disks?
Attach two cells in a fiber
Provide gap junctions
Electrically coupled cell group
Describe the mechanism of Ca release from SR
Ica channels open during Phase 2 plateau
Influx of trigger Ca
Causes calcium release channels in SR to open
Ca induced Ca release
What molecule effects the contractile state? How?
Catecholamines (isoproterenol or norepinephrine)
Increase available Ca levels
Wall tension prior to contraction
Increases with increased EDV as per law of la place
Approx. by end diastolic pressure
Relationship between EDV and cardiac performance
Increased venous return --> increased cardiac output
Force against which the cardiac muscle is working in systole
High afterload degrades ventricular performance
Approx. by systolic pressure
Variables of cardiac performance