Lecture

• Heart murmurs and skipped beats are pertinent to heart disease
• Mitral stenosis: is the stiffening of the bicuspid valve. It's caused by the increased back pressure into the left atria.
• The stretch of the left atria caused by mitral stenosis causes it to undergo hypertrophy to thicken. This causes for decreased space within the atria
• Mitral regurgitation: improper closure of the bicuspid valve so blood backflows into the left atrium. This causes less blood to be available for the rest of the body and decreases pressure within the heart.
• Mitral valve prolapse: occurs when the mitral valve opens and gets stuck in the extended position. Asymptomatic for the first few years with females having a higher risk. You could also hear a mid-systolic click
• Aortic stenosis is similar to mitral stenosis is associated LVH and left sided heart failure instead of right
• Aortic stenosis is occurs in people aged 70 to 90 and could lead to angina due to decreased cardiac output.
• Aortic regurgitation causes an increase in EDV/ESV which leads to LVH. This can result in bounding radial due to increased stroke volume.
• Aortic prolapse doesn't exist cuz someone would be dead if they had it
• 70% of the population is right dominant for the RCA with 10% being left and 20% being codominant; if ur codominant ur chilling frfr
• Coronary bloodflow is regulated centrally by the ANS and locally regulated by autoregulation.
• Q=perfusion, P=driving pressure and R=resistance; the formula is Q=P/R
• Metabolic hypothesis states that if there is an increased O2 demand or decreased O2 supply, chemical mediators are released
• Vasodilatory substances: adenosine, H+, K+, Co2, NO and prostaglandins
• NO is produced by coronary arteries and its a very potent vasodilator
• NO decreases R which in turn increases Q. It's release always increases with hypoxemia
• SNS stimulation does not allow coronary arteries to vasoconstrict
• Systole decreases coronary perfusion because while driving pressure is increased, resistance is increased a lot more
• BCP contributes to increasing the chance of getting ischemic heart disease
• Factors that decrease O2 supply: atherosclerosis, thrombosis, vasospasm, shock, poor perfusion pressures, respiratory pathologies and anemia
• Factors that increase demand of O2: increase in preload/afterload, SNS stimulation, stress, exercise, sex, fever and sympathomimetics
• Patho of ischemia is decreased P, decreased vessel diameter, decreased Q time, increased metabolic demands decreased glycogen stores and a loss of Ca+/K+ ions
• Zones 1 is infarction, zone 2 is hypoxic cell injury and zone 3 is ischemic zone

  
• The cells in zone 1 are dead, cells in zone 2 can recover if the issue is fixed.
• Cardiac impulses can't be sent through zones of infarction which means they bounce around and are uncoordinated
• Myocardial stunning occurs when blood flow is ok but the tissue is stunned and not functioning that well; temporary loss of fxn and contractility, this could last for hours to days after reperfusion
• Myocardial hibernation: persistently ischemic cells are ignored so demand is brought down to meet supply.
• Myocardial hibernation can be seen as low power mode and its seen with chronic angina or after an MI
• Myocardial remodeling is hypertrophy of myocytes caused by the RAAS/catecholamines
• Coronary syndromes are: stable angina, unstable angina, prinzmetal/variant angina, AMI(splits off into STEMI and NSTEMI) and sudden cardiac death
• Anginas don't have infarctions but have ischemia of heart tissue
• Atherosclerosis is the build up of plaque within an artery
• Arteriosclerosis is the hardening of arteries
• Cardiac pain travels up the afferent fibers and travels via the cardiac plexus and sympathetic chain
• The pleura are innervated but the lungs are not
• 25% of cardiac events have reproducible effects so don't use only this as a tool of diagnosis
• Silent MIs have no s/s and make up about 1/3 of them
• Prinzmetal/variant angina is a temporary spasm that can happen in healthy vessels
• Don't get angina PTs to lie down
• Giving NTG to someone with stable angina reduces R