Effect of Potassium and Calcium Ions on Heart Function

In the discussion of membrane potentials in Chapter 5, it was pointed out that potassium ions have a marked effect on membrane potentials, and in Chapter 6 it was noted that calcium ions play an especially important role in activating the muscle contractile process. Therefore, it is to be expected that the concentration of each of these two ions in the extracellular fluids should also have important effects on cardiac pumping.

Effect of Potassium Ions. Excess potassium in the extracellular fluids causes the heart to become dilated and flaccid and also slows the heart rate. Large quantities also can block conduction of the cardiac impulse from the atria to the ventricles through the A-V bundle. Elevation of potassium concentration to only 8 to 12 mEq/L—two to three times the normal value—can cause such weakness of the heart and abnormal rhythm that this can cause death.

These effects result partially from the fact that a high potassium concentration in the extracellular fluids decreases the resting membrane potential in the cardiac muscle fibers, as explained in Chapter 5. As the membrane potential decreases, the intensity of the action potential also decreases, which makes contraction of the heart progressively weaker.

Effect of Calcium Ions. An excess of calcium ions causes effects almost exactly opposite to those of potassium ions, causing the heart to go toward spastic contraction. This is caused by a direct effect of calcium ions to initiate the cardiac contractile process, as explained earlier in the chapter.

Conversely, deficiency of calcium ions causes cardiac flaccidity, similar to the effect of high potassium. Fortunately, however, calcium ion levels in the blood normally are regulated within a very narrow range. Therefore, cardiac effects of abnormal calcium concentrations are seldom of clinical concern.

Was this article helpful?

+7 -4
Getting Rid Of Warts Forever

Getting Rid Of Warts Forever

All wart sufferers, this is the day to stop the shame. How I Got Rid Of My Warts Forever and How You Can Get Rid Of Warts Naturally In 3 Days. With No Blisters, No Scars, And No Pain Without medications or expensive procedures. All by applying a simple, very natural and unbelievable FREE substance that can be found in almost every household.

Get My Free Ebook


Responses

  • Mark
    What are the effercts of potassium and calcium ions on heart function?
    4 years ago
  • folcard
    What is the action of potassium ions on heart?
    4 years ago
  • dina
    What is the effect of decreased potassium ion on the heart?
    4 years ago
  • Michael
    How is the heart affected by potassium and calcium?
    3 years ago
  • laura
    What is the pathophysiology calcium ion and cardiac function free download?
    3 years ago
  • kedija
    What causes dilated flaccid heart?
    3 years ago
  • ALOISIA
    How increased concentration of calcium ion affect heart rate?
    3 years ago
  • Luukas
    How do calcium ions affect the action potential?
    3 years ago
  • Lilly
    What is the effect of an increase in potassium ions on cardiac muscle cells?
    3 years ago
  • thomas
    What is the effect of excess calcium ions in the body?
    3 years ago
  • veera linnasalo
    Why potassium ion decreases heart contraction?
    3 years ago
  • nea l
    How increased calcium and potassium affect heart rate?
    3 years ago
  • angelica pugliesi
    How the potetium ion dilate the heart membrane?
    3 years ago
  • John
    What is the effect of excess calcium and potassium ions on the heart?
    3 years ago
  • Isabelle Johnstone
    What effect does calcium have on heart rate?
    3 years ago
  • outi yl
    What is the funcrion of potassium and calcium in dialation and constrition?
    3 years ago
  • Greta
    Does calcium increase heart rate?
    3 years ago
  • Farrah
    Does your calcium levels effect your heartrate?
    3 years ago
  • grover mcnemar
    How ions affects cardiac muscle?
    3 years ago
  • kiros efrem
    Why does potassim reduce cardiac muscle contraction?
    3 years ago
  • kauko
    What are the efect of calcium to heart?
    3 years ago
  • belladonna burrowes
    What are the effects calcium in the heart?
    3 years ago
  • rowan
    How extracellular potassium ions decrease contractility.?
    3 years ago
  • Demsas Yonas
    What is the work of calcium ions in heart?
    3 years ago
  • Tuomas
    What will be the cardiac effect when potassium concentration increases two to three times?
    3 years ago
  • allie kerr
    Which ion contain normal heart function?
    3 years ago
  • mya davidson
    How does concentration of potassium ions cause fast heart rate?
    3 years ago
  • Euan Stevenson
    How does calcium ions affect the heart?
    3 years ago
  • Christina
    How does excess calcium affect the heart?
    3 years ago
  • saba
    Why potassium is more important than other ions in cardiac functions?
    3 years ago
  • fatima underhill
    Which effect on cardiac muscle is caused by calcium ion?
    3 years ago
  • irene
    Why does alot of calcium reduce heart contraction?
    3 years ago
  • Brenda
    How does sodium ion, potassium ion and calcium ion affect the conduction of the heart?
    3 years ago
  • asmait
    What is the effect of sodium ion, potassium ion and calcium ion in conduction of the heart?
    3 years ago
  • mebrahtu
    How potassium and calciun regulate our heart beat?
    3 years ago
  • cedivar
    How potassium and calcium ions regulate your heart?
    3 years ago
  • adelaide
    How potassium and calcium control heart beat?
    3 years ago
  • CASSIDY
    What are the actions of calcium and potassium on the body?
    3 years ago
  • togo headstrong
    How potassium ion slows heart rate?
    3 years ago
  • christin daecher
    How calcium and potassium ions level affect heart rate?
    3 years ago
  • kimi
    What effect on cardiac muscle is caused by calcium ions?
    3 years ago
  • niklas
    What does potassium do to cardiac contraction?
    3 years ago
  • kidane
    What is the effect of sodium ion on the body?
    3 years ago
  • janina hoffmann
    Why calcium increases heart rate?
    3 years ago
  • leena
    How does potassium ions affect the cardiac cycle?
    3 years ago
  • swen
    How does potassium influence cardiac cycle?
    3 years ago
  • frodo
    How calcium ions influence the cardiac cycle?
    3 years ago
  • lia bianchi
    How does calcium ion increase heart rate and force of contraction?
    3 years ago
  • SAMANTHA
    What is the action of the higher dose of calcium ions on heart?
    3 years ago
  • dario
    How calcium affects the heart?
    3 years ago
  • MEGHAN
    Does calcium decrease heart rate?
    3 years ago
  • primrose
    How calcium ion play vital role in heart action?
    3 years ago
  • pandora
    What are the effects of Na , Ca2 k ions on the heart muscles?
    2 years ago
  • olavi
    What is effect of calcium ions on heart rate?
    2 years ago
  • Celedor
    How calcium level effect cardiac impulse?
    2 years ago
  • selina hayward
    What effect does calcium have on cardiac contractikity?
    2 years ago
  • ottone
    What is the role of calcium ions in heart function?
    2 years ago
  • Rocco Arcuri
    How does excess potassium weaken heart contraction?
    2 years ago
  • ILSE
    How increase in potassium ion conc. affects heart muscles?
    2 years ago
  • kimi
    How does cardiac cycle influenced by Potassium ions?
    2 years ago
  • Carmela
    What is the effect of calcium and potassium ions on heart rate and force of contraction?
    2 years ago
  • jessica
    How excess potassium in ECF in heart cause dilation,flaccid and slow heart rate?
    2 years ago
  • Saradoc
    Which type of effect is produced by calcium ions and potassium ions?
    2 years ago
  • Cassandra
    Can calcium deficiency raise heart rate?
    2 years ago
  • mathias himmel
    Which type of effect is produced by calciumion in heart?
    2 years ago
  • Kiros
    Does calcuim afect potasium levels?
    2 years ago
  • otho
    Does an increase in calcium affect a cat's heart rate?
    2 years ago
  • Aziza
    Do calcium ions have a high concentration?
    2 years ago
  • steven
    How the potassium affects the cardiac muscle?
    2 years ago
  • brice
    How do sodium and pottassium ions affect heart rate?
    2 years ago
  • Elsa Piirto
    How calcium ions act on cardiac muscles?
    2 years ago
  • cosimo
    Why does potassium and calcium efdect your heart?
    2 years ago
  • ferumbras
    What an excess of potassium ions do to heart rate?
    2 years ago
  • josie
    HOW CAN INCREASE OF IONS IN BLOOD AFFECT HEART RATE?
    2 years ago
  • maire kasvio
    Where does Calcium ion effect cardiac cell physiology?
    2 years ago
  • yvonne furst
    What effect does increasing extracellular ca ions have on heart rate?
    2 years ago
  • ponto
    What are functions of calcium and potassium in the heart?
    2 years ago
  • Awet
    How do calcium and potassium imbalances affect cardiac action potentials?
    2 years ago
  • Marco
    What are the effects on the action potential physiology with an imbalance of potassium and calcium?
    2 years ago
  • Sandra
    How increase in potassium affects cardiac contraction?
    2 years ago
  • felix
    Does epinephrine affect calcium in the heart?
    2 years ago
  • Elina
    What happens when there is high concentration of calcium in the heart?
    1 year ago
  • aatos
    What does the pottasium and sodium ions do for the contractions pf heart?
    1 year ago
  • GABRIELLA
    Does high sodium and potassium levels increase heart rate?
    1 year ago
  • paul weiss
    How excess of potassiun in ECF causes heart to become flaccid and also slows heart rate?
    1 year ago
  • eliisa
    How does potassium increase affect on calcium levels?
    1 year ago
  • Cynthia
    How does the the heart receive Calcium?
    1 year ago
  • ulla-maj
    How do calcium ions affect cardiac cycle?
    1 year ago
  • gabriella
    Which ions increase the rate of heart beat when in blood?
    1 year ago
  • Emma
    What is the role of potassium in the heart?
    1 year ago
  • elia
    Does calcium affext conduction of heart?
    1 year ago
  • taneli taipale
    How muscle contraction affects heart rate?
    1 year ago
  • Jayden
    What is the role of calcium in heart contractions?
    1 year ago
  • Luigia
    Why does calcium play a role in cardiac muscle?
    1 year ago
  • Marina
    What is the physiology of potassium on heart function?
    12 months ago
  • Faizan
    How does slow calcium uptake affect heart rate?
    12 months ago
  • YVONNE
    What ions affect membrane potential in the heart?
    12 months ago
  • yvonne kohl
    Why does calcium decrease potassium?
    12 months ago
  • hannu
    What is the effect of temperature on potassium and calcium on heart function?
    12 months ago
  • kristian
    Does potassium follow calcium?
    11 months ago
  • robur
    Does potassium affect contractility?
    11 months ago
  • Arlo
    What happens to frog heart rate with sodiuym ,potassiun. and calcium?
    11 months ago
  • niklas ackermann
    Which type of effect produce by calcium ion?
    11 months ago
  • kade
    Does potassium increase heart rates?
    11 months ago
  • naomi
    What type of effect does potassium ion have on toads heart?
    11 months ago
  • leah
    Why would calcium decrease frogs heart rate?
    11 months ago
  • GEBRE
    How would increasing the concentration of calcium affect firing rate of autorythimc cells?
    11 months ago
  • james
    How does norepinephrine increase concentration of calcium ions in myocardium?
    11 months ago
  • MYRON
    What does sodium, calcium, and potassium do in contraction?
    11 months ago
  • aino
    Are sensetive to which ions cells in the heart?
    11 months ago
  • Daniela Rothstein
    How does action potential increase heart rate?
    11 months ago
  • Mary Ward
    How does calcium effect cardiac action potential?
    11 months ago
  • SARI
    How the heart works potassium sodium conduction?
    11 months ago
  • Maureen
    Does caffeine pump calcium ions out of muscles?
    11 months ago
  • Largo
    How does calcium influence cardiac infarction?
    11 months ago
  • leon lange
    How potassium afects cardiac rythms?
    10 months ago
  • Sara Abaalom
    How does calcium, potassium, sodium and magnesium affect muschles and the heart?
    10 months ago
  • nuguse
    How do electrolytes affect the heart contraction?
    10 months ago
  • laura
    What effect does increasing calcium ions have on the heart?
    10 months ago
  • vanessa
    What does the sodium calcium antiporter do?
    10 months ago
  • MINTO BRANDYBUCK
    What is mild decrease in contraction of the heart?
    10 months ago
  • Gustavo
    How do levels of extracellular calcium affect cardiac function?
    10 months ago
  • mathias
    How is calcium tied to heart rate?
    9 months ago
  • haben
    How does the amount of potassium in your blood effwect heart rate?
    9 months ago
  • DOREEN
    What effect does calcium have on cells?
    9 months ago
  • Milen Zula
    How do electrolytes impact heart and cirulation?
    9 months ago
  • Iacopo
    Why is K important in the heart?
    9 months ago
  • Selam
    What increases contractility of heart in terms of calcium ions?
    9 months ago
  • Karen
    What effect does calcium channel blockers have on action potential in the heart?
    8 months ago
  • jan
    Does K increase heartrate?
    8 months ago
  • petra
    How does the heart behave in the presence high extracellular ca2?
    8 months ago
  • tamara
    Does calcium affect blood cirulation?
    8 months ago
  • Markus
    Do calcium ions influence rate of heart contraction?
    8 months ago
  • Uta
    What change would occur if you added sodium ions to the heart?
    8 months ago
  • mehret
    Why does calcium stabilise the myocardium?
    8 months ago
  • estella
    How does excesss calcium slow down heart rate?
    8 months ago
  • Anni
    How does potassium cause arrhythmia physiology?
    8 months ago
  • demet
    What is the physiological role of calcium?
    8 months ago
  • elina hyyti
    What does high calcium do to a cardiac rhythm?
    8 months ago
  • Poppy
    What is the effect of increased calcium ions on the heart?
    8 months ago
  • KIBRA
    What effect does increasing extracellular calcium have on cardiac muscle contractibility?
    8 months ago
  • IMMACOLATA
    HOw does potassium affect cardiac rhythm?
    7 months ago
  • TUIJA
    How will calciumm ions help counteract the effectos of high blood k?
    7 months ago
  • longo button
    How does the body increase calcium ion concentration?
    7 months ago
  • BANAZIR
    How can heart rate be controlled through the actions of sodium and calcium and potassiums?
    7 months ago
  • david hansen
    What happensd when potassium is added to heart rate?
    7 months ago
  • addolorata
    How does calcium affect heart at cellular level?
    7 months ago
  • ARCHIE JUDGE
    What is the normal role of the calcium during the contractile phase of the heart?
    7 months ago
  • ORSO
    How does calcium work with heart beat?
    7 months ago
  • ambessa
    How does calcium effect heart muscle?
    7 months ago
  • Duenna
    What might happen to the beating of the heart is the blood concentration of calcium was increased?
    7 months ago
  • HAIDEN
    What happens if increase of potassium ions in heart?
    7 months ago
  • Aapo
    How does increased heart rate affect potassium channel?
    7 months ago
  • florian
    How does sodium affect heart contractions?
    7 months ago
  • zuzanna
    What is the role of calcium and potassium in cardiac function?
    7 months ago
  • hannu
    Which ion can cause the heart to go into spastic contractions?
    6 months ago
  • megan joyner
    How calcium effects muscle?
    6 months ago
  • Berhane
    How does high K affect cell mcgraw?
    6 months ago
  • Arianna
    How is calcium affected in health care?
    6 months ago
  • mathilda rahnasto
    How does potassium affect myocardial action potential?
    6 months ago
  • GOODWILL
    What role do these ions play in cardiovascular physiology?
    6 months ago
  • joni
    What role does calcium play in circulation?
    6 months ago
  • ulpu
    How overdose of ca 2 effect the heart?
    6 months ago
  • ferruccio
    How would an overdose of calcium affect the heart?
    6 months ago
  • Leroy
    What is the impact of ca , k on the heart, conduction system?
    6 months ago
  • craig
    How the heart works using ions?
    6 months ago
  • katrin
    How does sodium and potassium affect the celll?
    6 months ago
  • lexie
    How too LITTLE calcium affects the the heart muscle?
    6 months ago
  • juha
    How does potassium affect the heart muscle?
    6 months ago
  • aiace
    Does calcium increase contractility in the heart?
    5 months ago
  • Amaranto
    How calcium increase the threshold of membrane potentials?
    5 months ago
  • Steffen Osterhagen
    How does calcium affect the hearts conduction?
    5 months ago
  • Tancredi
    How would high magnecium and calcium impact the heart?
    5 months ago
  • annabella
    How calcium ion concentration affects on fetus organs?
    5 months ago
  • micah forbes
    How does the increase of calcium increase muscle contractivity?
    5 months ago
  • Eric Lucchesi
    Why is potassium concentration important for the heart physiology?
    5 months ago
  • Lena
    What does potassium do to electricity?
    5 months ago
  • Dehab
    How the calcium concentration affected the heart?
    5 months ago
  • Uwe Busch
    How does stopping calcium affect the heart?
    5 months ago
  • ALEKSANDER KENNEDY
    What is the effect of calcium ion on heart beat?
    5 months ago
  • demsas
    How do major ions effect the heart?
    5 months ago
  • Jukka Rasi
    What causes higher concentration of calcium ions in sarcomeres?
    5 months ago
  • letteria
    What role does sodium play on norepinephrine?
    5 months ago
  • Heikki
    How potassium, sodium, and calcium work in the heart?
    4 months ago
  • violetta
    How does potassium enter cardiac cells?
    4 months ago
  • max ebersbach
    How does epi effect calcium on heart ventricles?
    4 months ago
  • luca
    Why is the potassium channel in cardiac muscle ungated?
    4 months ago
  • adiam
    What are the effects of accumulating sodium ions and increasing calcium ions?
    4 months ago
  • Galileo
    What role does the potasium centre play in regulation of the heart and blood vessels?
    4 months ago
  • Andrew
    Is calcium ions found in the ECM?
    4 months ago
  • kevin fenstermacher
    How does calcium streat high potassium and complete heart block?
    4 months ago
  • judy
    What role does calcium play in cardiac action potential?
    4 months ago
  • abaalom
    Does reduced calcium decrease heart contractions?
    4 months ago
  • camelia chubb-baggins
    What happens when there is plague and calcium in lower portionof heart?
    4 months ago
  • NATALIE
    How does calcium stabilize cardiac cells physiology?
    4 months ago
  • rosa trentino
    How does pottasssium relates to heart?
    4 months ago
  • patricia
    What cation decreases contraction of the heart?
    4 months ago
  • Milly McKay
    What does sodium and potassium do to the heart cells?
    3 months ago
  • Florian
    What affects rate of contractions of the heart?
    3 months ago
  • nancy
    How does plasma calcium effect heart function?
    3 months ago
  • Jennifer Junker
    How does sodium affect heart failure at the cellular level?
    3 months ago
  • aman
    How can imbalances in sodium, potassium, or calcium affect the electrical activity of the heart?
    3 months ago
  • fethawi
    Does calcium have an impact on potassium levels?
    3 months ago
  • ORA CARR
    How does calcium regulate heart rate?
    2 months ago
  • pansy
    What are effects of decreased heart pumping?
    2 months ago
  • CHIARA CALABRESE
    How does potassium concentration effect cardiac myocyte action potential contractility?
    2 months ago
  • Ralph
    What high calcium level affects the heart?
    2 months ago
  • pamphila
    How does sodium levels affect heart function?
    2 months ago
  • principio
    What does calcium do to the heart muscles?
    2 months ago
  • anna-liisa
    How do low level electrical pulses affect prostate?
    2 months ago
  • celendine
    Why does low calcium cause increase sodium permeability heart?
    2 months ago
  • tiina
    What does calcium do to potassium, sodium, and magnesium when the heart contracts?
    2 months ago
  • Chanel
    How does the heart action potential work potassium and calcium?
    2 months ago
  • selam
    How does sodium affect myocardium?
    2 months ago
  • PERVINCA HOGPEN
    How does calcium magnesium and potassium affect heart rate?
    2 months ago
  • Grimalda
    What effect will a high calcium have on myocardial contraction (see discussion on digitalis)?
    2 months ago
  • TRAVIS
    How poytasium and calcium act on heart?
    1 month ago
  • boyd
    HOW DOES THE HEART BEAT ION LEVEL?
    1 month ago
  • mollie morrison
    How calcium affects the level of potassium?
    1 month ago
  • Robyn
    How does calcium levels affect the heart?
    1 month ago
  • ADELFINA
    How does formaldehyde affect heart ca2?
    1 month ago
  • milena
    How calcium ions in cells increase heart rate?
    1 month ago
  • Caradas
    What potassum does to the heart on a cellular level?
    29 days ago
  • aden
    Does high calcium affect heart rhythm?
    28 days ago
  • ANETTE
    How does sodium impact heart function?
    27 days ago
  • Kinfe
    What will be the effect, if the dose of calcium ions is increased?
    21 days ago
  • jessica
    How does potassium affect cadiac conduction?
    20 days ago
  • bernd
    Does Ca ions increase or decrease HR?
    19 days ago
  • juhani
    Why does extra calcium increase the force on contractility with the heart?
    18 days ago
  • MAGGIE
    How sodiun, potasium,calcium affect heart rate.?
    17 days ago
  • cailyn mckenzie
    How ecf potassium affects action potential?
    14 days ago
  • juan
    How does the lack of action potentials cause heart problems?
    11 days ago
  • gisella
    Which two cardiac functions are affected by electrolytes?
    10 days ago
  • kayla pilcher
    Which effects the heart more potassium or calcium?
    10 days ago
  • jolly
    What ions are important in maintain heart rhythm?
    6 days ago
  • Rosa
    How does calcium stabilize heart?
    6 days ago
  • OLO LIGHTFOOT
    How does potassium chloride affect the heart?
    5 days ago
  • virginio monaldo
    How does sodium ions affact heart rate?
    3 days ago

Post a comment