Contractility

Discussion in 'Step I' started by aspiringmd1015, Aug 5, 2015.

  1. aspiringmd1015

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    does Contractility increase w/ Increased HR? BRS says it does bc w/an increased HR, you'll have a higher Intracellular ca2+ concnetration. Its not listed in FA so thats why im asking.
     
  2. elbandito123

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    Not necessarily. Things that affect heart rate have a chronotropic effect, while things that affect contractility will have an inotropic effect. While a lot of times we will see both an increase in contractility and heart rate together (ie. sympathetic activation), that is not the rule. For instance, the drug Digoxin will have a positive inotropic effect, but will have a negative / no effect on chronotrophy. Hope this helps.
     
  3. aspiringmd1015

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    i get what youre saying, but it didnt answer the context of what my questoin was asking, i wasnt asking if chronotropic and inotropic effects will always be the same, im asking if by increasing your HR(chronotropic) can increase your contractility, A/c To BRS, its true. Its not mentoined in FA so its either its something they left out, or not important enough.
     

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