GMS 6530 cardiac Exam with complete
solutions 2024/2025
Sympathetic innervation - ANSWER-- NE binds beta-1 receptors
- activates cAMP second-messenger system
- opens Ca2+ channels in sarcolemma
Parasympathetic innervation - ANSWER-- ACh binds muscarinic receptors
- opens K+ channels in nodal cells allowing outflow
- hyperpolarizes them slowing HR down
K+ - ANSWER-- electrolyte with greatest chronotropic effect
- hyper - excess diffuses into myocytes, slowing HR & causing irregularity
- hypo - hyperpolarizes cells, causing need for increased stimulation
Ca2+ - ANSWER-- hyper - increases HR & contractility
Na+ - ANSWER-- hyper - increases HR
% of capillaries shut down at any given time - ANSWER-- 75%
Arteriosclerosis - ANSWER-- harding of arteries with age
- decrease in elastic tissue
Atherosclerosis - ANSWER-- build up of lipids that form plaque
Vasomotor center of medulla - ANSWER-- stimulates most BV to contract with the
exception of the vessels in heart
Physiologic hypertrophy - ANSWER-- exercise, pregnancy
, - cardiomyocytes increase in length and width
- balanced enlargment of chambers
Pathologic hypertrophy - ANSWER-- concentric hypertrophy
- cardiomyocytes increase in width
- wall and septal thickening
- loss of chamber area
beta agaonists - ANSWER-- epi, isoproterenol
- dopamine
- dobutamine
dopamine - ANSWER-- shock
- beta 1 agonst
-increase contractility
- increase HR
- increase renal flow
- IV only, short 1/2 life, tachycardia, tolerance, increased mortality
dobutamine - ANSWER-- end-stage shock
- beta 1 agonist at low dose
- alpha 1 agonist at high dose
- increase contractility
- modest decrease in afterload
- short-term cardiac support
- IV only, tolerance, pro-arrhythmic, increased mortality
Phosphodiesterase inhibitor - ANSWER-- PD3 inhibitors
- milrinone
Milrinone - ANSWER-- end-stage shock
- inhibits PDE > increases cAMP
- increase cAMP = increase in contractility & SV
- increase cAMP = decrease afterload (vasodilation)
- little/no change in HR
- hypotension, proarrhythmia, increased mortality (may be lessened with
concurrent beta blocker)
Cardiac glycosides - ANSWER-- digitalis (digoxin)
- increase contractility
- increase SV
solutions 2024/2025
Sympathetic innervation - ANSWER-- NE binds beta-1 receptors
- activates cAMP second-messenger system
- opens Ca2+ channels in sarcolemma
Parasympathetic innervation - ANSWER-- ACh binds muscarinic receptors
- opens K+ channels in nodal cells allowing outflow
- hyperpolarizes them slowing HR down
K+ - ANSWER-- electrolyte with greatest chronotropic effect
- hyper - excess diffuses into myocytes, slowing HR & causing irregularity
- hypo - hyperpolarizes cells, causing need for increased stimulation
Ca2+ - ANSWER-- hyper - increases HR & contractility
Na+ - ANSWER-- hyper - increases HR
% of capillaries shut down at any given time - ANSWER-- 75%
Arteriosclerosis - ANSWER-- harding of arteries with age
- decrease in elastic tissue
Atherosclerosis - ANSWER-- build up of lipids that form plaque
Vasomotor center of medulla - ANSWER-- stimulates most BV to contract with the
exception of the vessels in heart
Physiologic hypertrophy - ANSWER-- exercise, pregnancy
, - cardiomyocytes increase in length and width
- balanced enlargment of chambers
Pathologic hypertrophy - ANSWER-- concentric hypertrophy
- cardiomyocytes increase in width
- wall and septal thickening
- loss of chamber area
beta agaonists - ANSWER-- epi, isoproterenol
- dopamine
- dobutamine
dopamine - ANSWER-- shock
- beta 1 agonst
-increase contractility
- increase HR
- increase renal flow
- IV only, short 1/2 life, tachycardia, tolerance, increased mortality
dobutamine - ANSWER-- end-stage shock
- beta 1 agonist at low dose
- alpha 1 agonist at high dose
- increase contractility
- modest decrease in afterload
- short-term cardiac support
- IV only, tolerance, pro-arrhythmic, increased mortality
Phosphodiesterase inhibitor - ANSWER-- PD3 inhibitors
- milrinone
Milrinone - ANSWER-- end-stage shock
- inhibits PDE > increases cAMP
- increase cAMP = increase in contractility & SV
- increase cAMP = decrease afterload (vasodilation)
- little/no change in HR
- hypotension, proarrhythmia, increased mortality (may be lessened with
concurrent beta blocker)
Cardiac glycosides - ANSWER-- digitalis (digoxin)
- increase contractility
- increase SV
