Adult Coronary Artery Pathology Flashcards
what did Alexis Carrel recognize in the 1910s?
first to understand and recognize how angina and stenosis were related in canine models
who is Claude Beck and what did he develop?
developed methods to perfuse animal hearts by attaching adjacent tissues to form collateral blood flow to ischemic myocardium
what did Arther Vineberg discover?
implanting the internal mammary artery, through a tunnel in the myocardium, in animals, that shoed communication developed b/w the IMA and the coronaries
who is the “Father of Open Heart”
C. Walton Lillehei
first surgeon to correct a variety of congenital heart defects that were previously considered untreatable
what happened when the first use of IMA as a direct graft?
during a procedure, a right coronary artery was too damaged, and in desperation, William longhair placed an IMA as a direct graft to restore the flow
what did Sones and Shirey demonstrate?
feasibility of selective coronary arteriography by using a catheter to inject contrast solution into the coronary Ostia
what is coronary circulation?
the nourishment of the heart tissues via the heart’s own vessels
what are the two main coronary arteries that branch off of the aorta and have many sub branches that supply oxygenated blood to the heart?
right coronary artery
left main coronary artery
what is coronary dominance?
refers to which coronary artery feeds the PDA that supplies the inferior wall of the heart
what does it mean to be considered right coronary dominant?
one’s RCA feeds the PDA
ischemia results from
an imbalance in oxygen supply or demand
what is angina pectoris
clinical manifestation of ischemic myocardial tissue that is temporally, or permanently injured
what are typical anginas symptoms
mild discomfort
severe chest pain
pain radiating to the arms, shoulders, neck, jaw or back
what triggers stable angina
physical activity , which increases the myocardial oxygen demand
variant angina occurs when?
occurs mostly exclusively at rest and is not precipitated ny exertion
what is predominantly a disease of the left ventricle?
Acute MI
what does acute MI result in?
necrotic myocardial tissues that is permanently injured
what is the difference between unstable angina and acute MI in the lumen?
unstable angina has partial lumen obstruction
complete lumen obstruction will cause acute MI
what might occur any time after myocardial infarction, especially if left atrium is enlarged
arterial fibrilation
what is the most common complication of myocardial infarctions?
arrhythmias
what are other complications of acute MI
ventricular fibrillation (VF) ventricular tachycardia (VT)
what is ventricular fibrillation?
essentially no blood is being pumped to the heart
usually seen in sudden cardiac death
what is ventricular tachycardia
significantly decrease the amount of blood pumped through the heart and increases oxygen demand
what is extreme LV failure called?
cariogenic shock
heart failure after an acute MI occurs predominantly as
left ventricular failure, caused by impaired LV function from infarcted left wall tissue
although less common, what are other causes of cardiac failure?
papillary muscle dysfunction or rupture
ventricular septal rupture
free wall rupture
what is a ventricular aneurysm
outpouching of scar tissue from a wide base in the ventricular wall
what are the characteristics of a true aneurysm?
- wide base
- walls composed of myocardium
- low risk of rupture
what is a risk of ventricular aneurysms?
have a low risk of rupture, but they can impair cardiac function causing heart failure
what is a pseudo aneurysm
an incomplete rupture of the free wall and is characterized by a narrow base with a saclike aneurysm extending from the wall
characteristics of pseudo aneurysm
- narrow base
- walls composed of thrombus and pericardium
- high risk of rupture
what is Dressler’s syndrome?
inflammatory response to injured tissue that develops in a few patients about 1-8 weeks after an acute MI
what does Dressler’s syndrome present as?
pericarditis
fever
joint pain
pericardial effusion
what is a recommended therapy for use after an acute MI when there is some form of LV dysfunction?
ACE inhibitors
what are used for hyperlipidemia and plaque stabilization
statins
ACS with non-ST segment myocardial infarction should not be given ____ if urgent surgery is considered likely
plavix
use for lipid-regulating drugs
treatment of hyperlipidemia
effects of nitrates (4)
- dilate arterial and venous systems
- increase blood flow through coronary arteries
- decrease cardiac workload
- reduce myocardial oxygen demand
effects of beta blockers
- decrease heart rate, bp, and contractility of the heart
- reduce myocardial oxygen demand
- reduce incidence of arrhythmias
calcium channel blockers effects
- dilate arterial system (including coronary arteries)
- decrease bp and contractility
- reduce cardial oxygen demand
- reduce incidence of arrhythmias
ACE inhibitors effects
dilate arterial and venous systems
decrease bp
anticoagulants effects
inhibit and prevent further clot formation
antiplatelets effects
inhibit thrombus formation by decreasing platelet aggregation
what is CABG (ACB)
performed to restore or increase blood flow to the myocardium
indications for ACB
- LM coronary artery stenosis
- LM equivalent disease, significant stenosis (70%) of the proximal LAD and CIRC
- multivessel disease, especially with high LAD stenosis or LV dysfunction
what is the primary vessel of importance and why?
LAD artery since it supplies a major portion of the myocardium, especially the left ventricle
the LAD must be grafted with the conduit that has the best latency rate. What does the latest research indicate this is?
the LIMA
what are other potential graft sites?
the RCA
PDA of the RC
marginal branch off the RCA
at 10 years, what is the LIMA and RIMA patency rate?
LIMA >95%
RIMA 80-90%
what is a free IMA bypass graft?
a IMA graft that is anastomosed to the aorta for blood supply
what are possible bypass graft conduits?
the IMA
SVG
radial artery
gastroepiploic artery
what is the leading indication for reoperation
vein graft atherosclerosis, which is buildup of fats, cholesterol and other substances in and on your artery walls (plaque), which can restrict blood flow
overall mortality with a first time elective CABG surgery is about
2%
what is the average length of stay after CABG
5-7 days
what does anti platelet therapy help in patients after an ACB
inhibits platelet adhesion in the new bypass grafts, especially in SVG grafts
main preoperative risk factor for develops of complications in surgery are
reoperation
lung disease
emergency surgery
renal dysfunction
plunged CPB time is an indication for
preoperative MI
bleeding
respiratory complication
cerebrovascular accident
coronary artery disease results from
progressive blockage of the coronary arteries by atherosclerosis
risk factors of CAD
hyperlipidemia hypercholesterolemia cigarette smoking hypertension diabetes obesity physical inactivity
non modifiable risk factor for CAD
family history of disease, age > 65, gender (time as high in men as women)
class I classification of CAD
no limitation of physical activity
ordinary physical activity does not cause undue breathlessness, fatigue, or palpitations
class II classification of CAD
slight limitation of physical activity
comfortable at rest but ordinary physical activity results in undue breathlessness, fatigue, or palpitations
class III classifications of CAD
marked limitation of physical activity
comfortable at rest but less than ordinary physical activity results in breathlessness, fatigue, and palpitations
class IV classification of CAD
unable to carry on any physical activity w/o discomfort
symptoms at rest can be present
if any physical activity is undertaken, discomfort is increased
left ventricular aneurysm ( LVA) results from
the occlusion of major coronary artery that produces an extensive transmural infarction
what are the two most common presentations of left ventricular aneurysm?
ischemic syndromes and CHF
surgical procedures for LVA
standard aneurysmectomy
endoaneurysmorraphy
what is ventricular septal defect (VSD)
extensive myocardial damage subsequent to occlusion of a major coronary vessel may result in septal necrosis and rupture
when does VSD occur?
usually in the first week of an infarction
the presence of a VSD is suggested by
a loud holosystolic murmur that reflects the left to right shunting across the ruptured septum
surgery is indicated on an emergency basis for nearly all post infarction VSDs to prevent
the development of progressive multi system organ failure
aortic stenosis results from
thickening, calcification, and or fusion of the aortic valve leaflets which produce an obstruction to LV outflow
development of aortic stenosis in younger patients is from
AS usually develops on congenitally bicuspid valves
development of AS in order patients
AS is degenerative change in trileaflet valves
what layer is the collagen and elastic fibers?
tunica externa or adventitia
what layer is the smooth muscle of the cell
tunica media
what layer is the internal elastic membrane, connective tissue, endothelial cells and lumen
tunica intima
vasoconstriction is due to
high blood pressure
vasodilation is due to
low blood pressure
do arteries or veins have more smooth muscle in their walls?
arteries have more smooth muscle in their walls than veins
what comes off the LCA
LAD
circumflex
diagonal
marginal
what comes off the RCA
PDA
marginal
if the blood supply to the heart muscle is cut off entirely, what happens
a heart attack or MI may occur
stable angina
triggered by physical or mental exertion
resolves with rest or meds
variant angina
occurs spontaneously
vasospasm
responds to meds
unstable angina
unpredictable may be caused by thrombus may happen at rest rest and meds do not help, may progress acute coronary syndrome that can lead to MI
ischemia
- reversible
- t wave changes
- coronary artery cannot supply enough oxygen rich blood to meet the heart’s needs to cells resume contraction
injury
- reversible
- ST abnormalities
- coronary artery cannot supply enough oxygen rich blood to meet the heart’s needs
- becomes stunned and recovery is delayed
infarction
- irreversible cell death
- pathological Q wave
- coronary artery cannot supply enough oxygen rich blood to meet the heart’s needs, complete depletion occurs, necrosis of cells results
MI tends to affect what ventricle more
left
NSTEMI
occluding thrombus sufficient to cause tissue damage and mild myocardial necrosis
- elevated cardiac enzymes
- ST depression
STEMI
- complete thrombus occlusion
- more severe symptoms
- elevated cardiac enzymes
- ST elevations on ECG or new LBBB
