Cardio Flashcards
What does angina mean?
Chest pain due to reduced blood flow (ischemia) to the heart
The coronary arteries supplying blood to the heart itself have more than 70% stenosis (note: <70% stenosis would be asymptomatic and 100% stenosis/ blockage would be an MI)
What are the 3 causes of holosytolic murmurs (same level of loudness throughout systole)?
- Tricuspid Regurgitation
- Mitral Regurgitation
- VSD (Ventricular Septal Defect)
What defect produces a continuous, “machine-like” murmur?
PDA (Patent Ductus Arteriosus)
*The reason it is continuous is an open PDA means there is a shunt causing blood to flow from aorta—> pulm. Arteries. This is outside the heart, so not dependent on systole or diastole.
You’re listening to the heart at the 4 different valves. What are the landmarks of where to listen?
AORTIC- 2nd intercostal space on the patient’s right/ right upper sternal border
PULMONIC- 2nd intercostal space on the patient’s left/ left upper sternal border
TRICUSPID- left lower sternal border on the patient’s left
MITRAL- 5th intercostal space on the patient’s left, mid-clavicular line
Are systolic murmurs always pathological? Diastolic murmurs?
Systolic murmurs can be normal/ innocent in kids, young thin patients, and pregnant women.
Diastolic murmurs are always pathologic!
The main side effect of statins is myopathy. What does that mean?
Problems with muscles. Muscle fibers not functioning properly, muscle aches
What does myalgia mean?
Muscle pain (a major side effect of statins)
Some symptoms of pericarditis= fever, leukocytosis, high ESR (inflammation). What does leukocytosis mean?
High WBC count
What EKG changes are seen in acute pericarditis? How is this distinguished from ischemia like in an MI?
ST elevations all over the EKG (whereas, just in one heart region in ischemia) and/or PR depression
What is the most common cause of pericarditis?
A viral infection- often Coxachie
What does myopericarditis mean?
Myocarditis + pericarditis (patient has inflammation of the myocardium/ heart muscle AND the pericardium/ heart covering)
If a patient has an elevated JVP (jugular venous pressure), what does that tell you?
Fluid from the RA is getting backed up (because the jugular vein turns into the SVC and dumps into the RA). There’s increased pressure in the RA and some heart pathology going on (ex: pericarditis)
What EKG findings do you see in cardiac tamponade?
Low-voltage QRS (lower peaks) and electrical alternans
The electrical recording isn’t as strong because the heart is swinging around in fluid in the pericardial sac
What are the 3 layers of the pericardium (heart covering)? Other heart layers?
Fibrous pericardium—> parietal layer of the serous pericardium—> visceral layer of the serous pericardium a.k.a. Epicardium—> myocardium (heart muscle)—> endocardium (inner lining)
Which valves have chordae tendonae (heart strings attached to papillary muscles)?
The AV valves (tricuspid + mitral/bicuspid)
Conceptually, what does cardiac output (CO) mean? What is its equation?
CO is the amount of blood your heart pumps out per minute (L/min)
CO= SV * HR
Conceptually, what is stroke volume (SV)? What is its equation?
The volume of blood that gets pumped out (closely related to the contractility of the heart) SV= EDV- ESV (blood your heart is filled with at the end of diastole minus blood that’s still in your heart after it contracts in systole= blood that got pumped out)
Conceptually, what is contractility?
How hard the heart muscle squeezes (closely related to stroke volume, or SV)
Conceptually, what is myocardial oxygen demand?
How much oxygen/ energy the heart needs to do its work
Conceptually, what is preload? Afterload?
Preload- VOLUME of blood available to load into the LV before it gets pumped out
Afterload- PRESSURE the LV has to develop/ overcome to pump
Conceptually, what is ejection fraction (EF)? What is normal EF?
% of blood pushed out the LV with each heartbeat
Normal= about 55-60%
What is the ejection fraction (EF) formula?
SV/ EDV= (EDV-ESV)/ EDV
What’s getting pumped out over the total amount of blood the heart initially was filled with before it pumped
Conceptually, what is mean arterial pressure (MAP)? What are the 2 equations?
The average pressure in arteries during 1 cardiac cycle.
MAP= CO* Resistance (TPR or SVR)
…and…
MAP= 2/3 diastolic BP + 1/3 systolic BP
(*you can’t take the average BP like a normal mean bc 2/3rds of time is spent in diastole, 1/3rd in systole and you have to account for that)
What happens to BP and blood flow in (1) vasoconstriction and (2) vasodilation?
(1) vasoconstriction: increases BP; decreases blood flow
(2) vasodilation: decreases BP; increases blood flow
What’s the difference between VASOconstriction and VENOconstriction?
Vasoconstriction is talking about the arteries (away from the heart)
VENOconstriction is talking about the veins (to the heart)
How does VENOconstriction effect preload?
It increases it because you are increasing “milking” of blood up to the heart, so the heart will fill with more blood
What 4 heart-related things happen when the sympathetic nervous system is activated?
(1) increase in HR (NE released from sympathetic nerves—> increases cAMP—> stimulates more Na+ to come in through channels—> faster depolarization/ contraction of heart)
(2) increase in contractility
(3) VENOconstriction (increase in “milking” up of blood to the heart= increase of preload)
(4) vasoconstriction (increases BP, decreases blood flow to less critical organs like GI organs because skeletal muscles, for example, are more important in a fight or flight situation)
What 4 things does cardiac output (CO) depend on?
(1) preload (2) afterload (3) contractility (4) HR
Describe blood flow all the way through the heart
Enters SVC/ IVC—> RA—> tricuspid valve—> RV—> pulmonic valve—> pulmonary artery—> lungs to get oxygenated—> pulmonic veins—> LA—> mitral (bicuspid valve)—> LV—> aortic valve—> aorta—> out to body
What are all the heart valves and how many leaflets do they each have normally?
AV valves= tricuspid valve and mitral (bicuspid) valve
Semilunar valves= pulmonic and aortic valve
They all have 3 leaflets except mitral (bicuspid) valve only has 2.
The ductus arteriosus (shunt from pulmonary arteries to aorta to bypass lungs) normally closes at birth. What is the remnant of this called?
Ligamentum arteriosum
What are the 3 shunts in fetal circulation and what do they bypass?
(1) DUCTUS VENOSUS- shunts blood coming in from umbilical vein to IVC (bypasses hepatic circulation)
(2) FORAMEN OVALE- shunts most of the blood from the RA to the RV (bypasses the RV to the lungs)
(3) DUCTUS ARTERIOSUS- shunts blood that went through the RV—> pulmonary arteries to the aorta (bypasses the lungs)
* The liver doesn’t need all the blood flow and the lungs are filled with amniotic fluid and not yet working so that’s why blood skips these structures
In terms of veins and arteries/ oxygenated and deoxygenated blood, what is different about fetal circulation (in the womb) vs. adult circulation?
Veins are to the heart, arteries away from the heart (same)
Veins carry OXYGENATED blood, arteries carry deoxygenated blood as it gets distributed to tissues (opposite)
What does “placental abruption” mean?
The placenta detaches from the uterus (usually the baby dies)
What is cyanosis
Blue-ish discoloration of skin due to low oxygen saturation
What do prostaglandins (PG’s) like E1= Alprostadil and E2 do to the ductus arteriosus (DA)? How about Indomethacin?
PG’s keep the DA open/ patent. Indomethacin is an NSAID, so inhibits PG’s and therefore may help close the DA.
*The placenta provides a lot of PG’s to keep the DA shunt (pulm arteries—> aorta, bypassing lungs) open in fetal circulation. Once born, the DA normally closes. If it remains open/ patents, we may give Indomethacin to close it. If the baby has cyanosis (lack of oxygen), we may give PG’s to keep it open (aortic pressure rises after birth so will now shunt aorta—> pulm arteries) to get more blood into lungs for oxygenation until we fix the underlying problem.
(Congenital heart disease) Why is a right to left shunt worse than a left to right shunt?
In a left to right shunt, oxygenated blood from the left side of the heart is shunted to the right, causing volume overload. This causes a heart murmur, but only becomes a real problem (cyanosis, “blue kids”) if it is left untreated for a long time and the pulmonary circuit builds up so much pressure (pulm hypertension) that the shunt switches directions. NOT AS BAD
In a right to left shunt, deoxygenated blood from the right side of the heart is shunted to the left to get pumped out to the body—> cyanosis (“blue babies”). BAD!!
About 25% of people have a patent (open) foramen ovale (fetal shunt between atria). Is this a problem? If it can be, why?
Usually not a problem because just a little oxygenated blood from the higher pressure LA will leak into the lower pressure RA—> higher pressure in the RA. BUT, can lead to paradoxical emboli (if you get a blood clot, it can come in through the RA and take advantage of the shunt/ opening and move directly to the LA even though that’s against the pressure gradient and get pumped out systemically possibly leading to a stroke) **also seen in atrial septal defect (ASD)
If the septal defect is smaller, will the heart murmur be softer or louder?
Louder (blood traveling through a smaller space will produce a louder sound)
Smaller septal defect= less symptoms but louder heart murmur
What does tachypnea mean?
Rapid, shallow breathing
What’s central cyanosis vs peripheral cyanosis?
Central cyanosis- heart is pumping enough blood (normal CO, warm extremities) but it doesn’t have enough oxygen in it
Peripheral cyanosis= heart is not pumping enough blood (HF), which is why you’re body isn’t getting enough oxygen
Describe Tetrology of Fallot.
Congenital defect/ displacement of the infundibular septum (smooth funnel connecting the RV and the pulmonary arteries). Leads to 4 problems: (1) narrowing/ stenosis of the pulmonic valve (2) displacement/ overarching of the aorta (3) hypertrophy/ thickening of the RV walls (4) ventricular septal defect (VSD)
What is angina? Why would giving nitrates help?
Angina= chest pain from ischemia/ decreased blood flow to the heart
Nitrates primarily cause venodilation, but they also cause vasodilation. The vasodilation of the coronary arteries in the heart will open up the arteries where the infarct is so the infarct isn’t blocking as much/ isn’t as much of a problem
What is the main mechanism of nitrates?
Venodilation (decreasing preload to the heart)
But they also cause vasodilation (decreasing afterload on the heart)
During exercise, where do you get vasoconstriction? Where do you get vasodilation? Explain.
You get vasoconstriction as a part of the sympathetic response increasing BP and decreasing blood flow to less critical organs at the time, like the gut. You get vasodilation to increase blood flow to muscles.
Why do you get cyanosis in Tetrology of Fallot?
2 reasons:
1) the aorta is misplaced/ overarching so you get shunting of deoxygenated blood from the RV through the aorta and out to the body
2) there is stenosis of the pulmonary artery so less blood gets through to the lungs for oxygenation
Which valve defects cause systolic heart murmurs?
Tricuspid insufficiency, mitral insufficiency, pulmonic stenosis, and aortic stenosis
**Remember: AV valves are open, semilunar valves are closed in systole. Stenosis= problem with opening the valve. Insufficiency= regurgitation= problem with closing the valve.
Which valve defects cause diastolic heart murmurs?
Tricuspid stenosis, mitral stenosis, pulmonic insufficiency, and aortic insufficiency
**Remember: AV valves are open, semilunar valves are closed in systole. Stenosis= problem with opening the valve. Insufficiency= regurgitation= problem with closing the valve.
Which layer of the heart is the most vulnerable to ischemia (such as angina)?
The subendocardium (because it is the layer that is furthest away from the coronary arteries, so receives less blood flow)
What does inotrophy mean?
Contractility (agents that alter contractility)
What blood vessels feed the heart/ supply the heart itself with blood?
Coronary arteries
What are examples of ischemic heart disease?
Stable angina, unstable angina, MI
*can result in sudden cardiac death or chronic ischemic heart disease (if chronic damage from ischemia progresses to CHF)
Describe stable angina
STABLE ANGINA- you have >70% stenosis in coronary arteries supplying the heart and this is a problem during exercise when your body needs to pump out more blood to meet increased metabolic demands (the blockage makes it harder to push blood through)
Does inspiration make heart murmurs louder or quieter? Expiration?
Inspiration makes right heart murmurs louder (negative pressure increases preload/ blood coming up through the SVC/ IVC and dumping into the right side of the heart)
Expiration makes left heart murmurs louder (positive pressure squeezes blood out of the lungs and into the left side of the heart)
What does standing up do to the intensity of heart murmurs (most murmurs, hypertrophic cardiomyopathy, and mitral valve prolapse)? Explain.
Standing up—> DECREASES PRELOAD (blood pools by gravity).
MAKES MOST MURMURS QUIETER (Less preload= less blood to flow through defected valve= less turbulent flow= quieter murmurs).
MAKES HYPERTROPHIC CARDIOMYOPATHY MURMUR LOUDER (Less preload= less blood to fill the LV and push the defect out of the way= more aortic outflow obstruction causing a murmur).
YOU HEAR THE MITRAL VALVE PROLAPSE CLICK EARLIER (Less preload causes the valve to be more floppy= more turbulent flow= murmur from ballooning out of valve heard sooner)
What does the Valsava maneuver (bearing down) do to the intensity of heart murmurs (most murmurs, hypertrophic cardiomyopathy, and mitral valve prolapse)? Explain.
Valsava=Bearing down—> DECREASES PRELOAD (squeezing abdominal muscles—> clamping off of IVC).
MAKES MOST MURMURS QUIETER (Less preload= less blood to flow through defected valve= less turbulent flow= quieter murmurs).
MAKES HYPERTROPHIC CARDIOMYOPATHY MURMUR LOUDER (Less preload= less blood to fill the LV and push the defect out of the way= more aortic outflow obstruction causing a murmur).
YOU HEAR THE MITRAL VALVE PROLAPSE CLICK EARLIER (Less preload causes the valve to be more floppy= more turbulent flow= murmur from ballooning out of valve heard sooner)
What is the valsava maneuver (phase II)?
Bearing down (like on the toilet or trying to blow out to make your ears pop with your mouth closed)
What does handgrip do to the intensity of the following heart murmurs: mitral regurgitation, aortic regurgitation, and VSD? Explain.
Handgrip—> INCREASES AFTERLOAD (due to increased SVR aka BP from you gripping those hand muscles)
MAKES THESE MURMURS LOUDER (increased afterload= increased pressure the LV has to pump against to get the blood out= so the blood will take the path of least resistance, for example, will go from LV->LA rather than LV->aorta in a mitral regurgitation= and more blood through bad valve= more turbulent flow= louder murmur)
What does handgrip do to the intensity of the following heart murmurs: hypertrophic cardiomyopathy, aortic stenosis, and mitral valve prolapse? Explain.
Handgrip—> INCREASES AFTERLOAD (due to increased SVR aka BP from you gripping those hand muscles)
MAKES HYPERTROPHIC CARDIOMYOPATHY MURMUR QUIETER (More afterload will make it even harder for blood to get out through the aorta= so less blood will make it through to aorta past the defect and high pressure= less turbulent flow= quieter murmur)
MAKES AORTIC STENOSIS MURMUR QUIETER (More afterload will make it even harder for blood to get out through the aorta= so less blood will make it through aorta= less turbulent flow= quieter murmur)
YOU HEAR THE MITRAL VALVE PROLAPSE CLICK LATER (More afterload/ pressure pushes the valve back in place= less turbulent flow= murmur from ballooning out of valve heard later)
What does rapid squatting do to the intensity of the following heart murmurs: aortic stenosis, mitral regurgitation, and VSD? Explain.
Rapid squatting—> INCREASES PRELOAD (kink veins in legs= increased “milking” up of blood to heart) and also afterload (increased SVR aka BP from you contracting muscles)
MAKES THESE MURMURS LOUDER (increased preload= increased blood that will go through the defected valves= increased turbulent flow= louder murmurs)
What does rapid squatting do to the intensity of the following heart murmurs: hypertrophic cardiomyopathy and mitral valve prolapse? Explain.
Rapid squatting—> INCREASES PRELOAD (kink veins in legs= increased “milking” up of blood to heart) and also afterload (increased SVR aka BP from you contracting muscles)
MAKES HYPERTROPHIC CARDIOMYOPATHY MURMUR QUIETER (More preload expands the LV and pushes the defect out of the way so it’s not such a problem= decreases turbulent flow= quieter murmur)
YOU HEAR THE MITRAL VALVE PROLAPSE CLICK LATER (More preload/ blood pushes the valve back in place/ makes it more crisp= less turbulent flow= murmur from ballooning out of valve heard later)
In general, if you have greater preload what will that do to the loudness of a murmur?
More blood flow through bad valve= louder murmur
Less blood flow through bad valve= quieter murmur
What is mitral valve prolapse?
Ballooning up of valve leaflets (note: more preload/ afterload will help push the valve back into place/ make it more crisp so it’s less of a problem and there’s less of a murmur. Less preload will make the valve even more floppy so it’s more of a problem and there’s more of a murmur.)
What does a crescendo-decrescendo murmur mean?
It gets louder, then it gets quieter again
What is total peripheral resistance (TPR) aka systemic vascular resistance (SVR)?
Pretty much the same thing as BP
Explain what endocarditis is.
Inflammation of the endocardium= inner layer of heart= infection of the valves.
(Example: patient may have vegetations= grape-like collections of bacteria on their valve from a strep epidermidis infection following a valve replacement surgery. These vegetations can go to anywhere in the body and cause lots of symptoms, like in fingernail beds causing splinter hemorrhages.)
How long does it take for the heart to beat in embryo?
4 weeks (heart is beating by week 4)
Is RA pressure higher or lower before birth? After birth?
RA pressure is higher before birth; lower after birth.
REMEMBER: right heart pressures are higher before birth (lungs not working). Left heart pressures are higher after birth (the right heart only has the job of pumping to the lungs, while the left heart has the greater job of pumping to the body)
Why would you give PG’s to a baby with Tetralogy of Fallot temporarily before that congenital heart defect can be surgically fixed?
PG’s will keep the ductus arteriosus open, allowing blood to shunt from the higher pressure aorta—> lower pressure pulmonary arteries= more blood flow to the lungs. Why does this help? In Tetralogy of Fallot, you have early cyanosis because (1) deoxygenated blood from the RV is shunting into the overarching aorta and (2) blood is having a hard time getting through the stenosed pulmonary artery to the lungs to get oxygenated. So you have the aorta pumping out deoxygenated blood and little oxygenated blood. By shunting some of that deoxygenated blood in the aorta back to the pulmonary arteries so they can get to the lungs (bypassing the stenosis early on in pulmonary artery), you are giving the blood a chance to get oxygenated by the lungs and making the cyanosis not as bad so the baby can live until surgery.
Why would you give PG’s to a baby with Total Anomalous Pulmonary Venous Return (TAPVR) temporarily before that congenital heart defect can be surgically fixed?
PG’s will keep the ductus arteriosus open, allowing blood to shunt from the higher pressure aorta—> lower pressure pulmonary arteries= more blood flow to the lungs. Why does this help? In TAPVR, you have the pulmonary veins dumping into the right heart (so oxygenated blood gets put back into compartment with deoxygenated blood). So, only the right side of your heart is working—> right side has more pressure than left side, unlike normal. So a PDA will cause shunting from the right side (pulmonary arteries)—> left side (aorta). This will help pump blood out to sustain life until surgery (you need a R—> L shunt to live in this condition).
What’s the difference between coarctation of the aorta that is pre-ductal and post-ductal? What does that means in terms of collateral artery development?
PRE-DUCTAL= the narrowing of the aorta is before the ductus arteriosus, so a PDA (patent/ open ductus arteriosus) would help by shunting blood across to the aorta after the problem. POST-DUCTAL= the narrowing of the aorta is after the ductus arteriosus, so the PDA doesn’t help because it would shunt blood across the aorta, THEN the blood would run into the problem of a narrowed aorta. In this case, the body would compensate by making new vessels= collateral vessels to feed the lower half of the body with blood.
Turner syndrome is associated with what heart problems?
Bicuspid aortic valve and coarctation of the aorta (“Turner syndrome turns the aorta into a problem”)
What heart problems are associated with Down syndrome?
Down syn is associated with endocardial cushions (giving rise to atrioventricular (AV) septum + valves) not developing right—> AV septal defect, ASD (atrial septal defect), and VSD (ventricular septal defect).
Babies born to diabetic moms are most likely to have what congenital heart problem?
Transposition of the great vessels
What is systolic BP associated with? Diastolic BP? (Options: CO, PVR, preload, afterload)
Systolic BP (pumping out) is associated with afterload (pressure the LV has to pump against) and CO (how much blood gets pumped out over a given time). Diastolic BP (filling) is associated with preload (blood that is available to fill the LV) and PVR (the blood that’s in the periphery and available to go back up to the heart)
What’s the difference between eccentric and concentric hypertrophy?
Eccentric= myocytes are added sideways/ in series (LV gets stretched out).
Concentric- myocytes are added on top of each other/ in parallel (LV thickens to where it looks like a bullseye).
In what case would you see both elevated JVP and enlarged liver?
Right heart failure
Because blood backs up to SVC—> jugular vein & IVC—> liver venous system
What is the feared complication of prolonged QT intervals on EKG?
TORSADES DE POINTES (“twisting of the points”).
This is a ventricular tachycardia arrhythmia with QRS (ventricular depolarization) getting smaller and larger and smaller and larger…
What is congenital long QT syndrome? What 2 specific disorders does this include?
You are born with defective Na/K channels in your heart—> takes longer for ventricles to depolarize and repolarize—> prolongs the QT interval on EKG (QT= whole systole; depolarization + repolarization). Prolonged QT=> Torsades de Pointes (can result in sudden cardiac death).
Includes: ROMANO-WARD SYNDROME (autosomal dominant) and JERVELL AND LANGE-NIELSEN SYNDROME (autosomal recessive, includes deafness).
You can get Torsades de Pointes (V tach arrhythmia with shifting waveforms of QRS getting smaller and larger and smaller and larger…) from prolonged QT intervals (systole= depol. + repol.). What are causes of this (hint: there are 5)?
Causes of prolonged QT—> Torsades de Pointes:
- Drugs (ABCD: antiArrhythmics 1a and 3, antiBiotics like macrolides, antiCychotics, antiDepressants, and antiEmetics (stop vomiting).
- Hypokalemia (low K+)
- Hypomagnesemia (low Mg2+)
- Hypocalcemia (low Ca2+) RARELY
- Congenital abnormalities (ex: congenital long QT syndrome)
* *Anti-arrhythmic drugs cause this if they prolong QT too much. Low K+/ low Mg can cause this bc these electrolyte abnormalities mess up ventricular depolarization.
V tach arrhythmia with shifting waveforms of QRS getting smaller and larger and smaller and larger…knows as “twisting of the points.” What is this called?
Torsades de pointes
When do you see peaked T waves?
Hyperkalemia (high K+) and early ischemia
When do you see U waves? (2 cases)
Hypokalemia (low K+) and bradycardia (low HR)
*they follow T waves
Inverted T waves on EKG may indicate what?
Ischemia or recent MI
What enables depolarization to travel from one myocyte to the next? (Note: this is different from skeletal muscle where cells are individually depolarized.)
Gap junctions
Think about the cardiac pacemaker (SA node, AV node) action potential. What does it mean to increase/ decrease the slope of phase 4?
Phase 4= ventricular diastole (resting/ refilling) but Na+ is slowly coming in through “funny channels” till it reaches threshold that triggers full-on depolarization.
Increase slope of phase 4= increase Na+ influx= increase rate at which you depolarize= increase HR (sympathetic NS and sympathomimetic drugs do this).
Decrease slope of phase 4= decrease HR (PNS, beta-blockers, and Adenosine do this).
Heart sounds: What is S1? S2?
S1= closure of mitral/ tricuspid valves (AV valves) S2= closure of aortic/ pulmonic valves (semilunar valves)
Explain the physiologic splitting of S2.
Inspiration—> increases venous return (blood dumped into right heart)—> since there’s more blood/ pressure in the right side of the heart, the pulmonic valve will take a little longer to close than the aortic valve—> subtle spit of the S2 heart sound
When do you hear S3 and S4 heart sounds- systole or diastole? Be specific.
Both are pathologic/ abnormal, heard in diastole. S3= early filling sound (heard right after S2). S4= late filling sound (heard right before S1).