CARDIAC PHYSIOLOGY IN DISEASE
CARDIAC DISEASE
• generally of 2 types
◦ rate/rhythm problems
◦ structural problems
• Varied pathophysiological reasons for them:
• • Congenital structural defects
• • Ischemic injury / infarction → fibrosis • Systemic diseases impacting cardiac
function / health
ANGINA
• pain/discomfort in chest due to lack of oxygen
• precursor to a heart attack
• caused by vasoconstriction/less blood flow - due to a narrow/blocked artery
◦ can be due to
▪ intense exercise
▪ atherosclerosis
▪ stress
▪ cold temp
▪ drug use
INFARCTION
• blocked blood vessel
• this leads to permanent death/necrosis of myocardium
MYOCARDIAC ISCHEMEIA
• due to atherosclerosis usually
• Rare factors affecting myocardial O2 delivery: Anaemia, excessive sympathetic
tone, or CO poisoning
• • At rest 90% of vessel needs to be blocked to cause symptoms but with exercise
even 50% of blockage will cause symptoms of myocardial ischemia.
• Some factors that affect whether a person develops coronary artery disease cannot
be modified. They include
◦ •Advancing age •Male sex •Family history
• Other risk factors for coronary artery disease can be modified or treated. These
factors include
CARDIAC DISEASE
• generally of 2 types
◦ rate/rhythm problems
◦ structural problems
• Varied pathophysiological reasons for them:
• • Congenital structural defects
• • Ischemic injury / infarction → fibrosis • Systemic diseases impacting cardiac
function / health
ANGINA
• pain/discomfort in chest due to lack of oxygen
• precursor to a heart attack
• caused by vasoconstriction/less blood flow - due to a narrow/blocked artery
◦ can be due to
▪ intense exercise
▪ atherosclerosis
▪ stress
▪ cold temp
▪ drug use
INFARCTION
• blocked blood vessel
• this leads to permanent death/necrosis of myocardium
MYOCARDIAC ISCHEMEIA
• due to atherosclerosis usually
• Rare factors affecting myocardial O2 delivery: Anaemia, excessive sympathetic
tone, or CO poisoning
• • At rest 90% of vessel needs to be blocked to cause symptoms but with exercise
even 50% of blockage will cause symptoms of myocardial ischemia.
• Some factors that affect whether a person develops coronary artery disease cannot
be modified. They include
◦ •Advancing age •Male sex •Family history
• Other risk factors for coronary artery disease can be modified or treated. These
factors include