Ischemic Heart Disease (Coronary artery disease) Flashcards
What is ischemic heart disease?
Narrowing or obstruction of the coronary arteries Sufficient to prevent adequate blood and oxygen supply to the myocardium (ischemia)
not getting enough blood
What may IHD lead to?
May progress to the point the myocardium is damaged (infarction)
What are two types of IHD etiology?
- Atherosclerotic
- Non-Athersclerotic
What is the most common IHD etiology?
Atherosclerotic
What are examples of non- Atherosclerosis causes of IHD? 3
- Embolus into coronary artery
- Trauma
- Coronary artery dissection
What does this image represent?
Plaque progression from a fatty streak on the intima to a superficial erosion of the endocardial layer
In terms of atherosclerotic plaque progression, when the thrombus forms, what does it occlude? and where does it usually occur?
- The lumen of the artery
- Distal to an arterial branching
What are some major risk factors for IHD? 5
- Age
- Smoking
- Diabetes mellitus
- Dyslipidemia
- Hypertension
What are some predisposing risk factors for IHD? 4
- Abdominal obesity
- Family history
- Obesity
- Physical inactivity
What is ischemia?
Decreased blood supply to the myocardium
What is an infarction?
Death or necrosis of tissue which results from prolonged ischemia
Can ischemia occur due to increased demand for blood?
Yes
Is ischemia reversible?
Yes
What is a total occlusion of blood flow to the tissue?
Infarction
Between ischemia and infarction which one is reversible?
Ischemia is reversible
What the most common causes of ischemia? 2
- Coronary artery disease
- Increased metabolic demand
What is coronary artery disease (CAD)?
Plaque in the vessel which impedes blood flow
How would someone have ischemia due to increased metabolic demand? 2
- Hypertrophy cardiomyopathy (more muscle)
- Aortic stenosis (more work or high afterload)
Everything downstream of the obstruction dies unless there is what?
Collateral circulation from another vessel
In terms of infarction, cell death starts to happen when? (Time frame)
Within 1 hour and is complete by 4
What are signs/ symptoms of ischemia/ Myocardial infarctions? 2, 8
- Angina Pectoris (chest pain)
- SOB
- Syncope
- Fatigue
- Can be silent (Asymptomatic)
- Sweating
- Nausea and vomiting
- Anxiety
What might a CXR show in terms of ischemic heart disease? 3
May show
- Pulmonary edema
- Cardiomegaly
- May appear normal
Where would we auscultate for ischemic heart disease?
S4, possible S3
What might we hear when we auscultate for ischemic heart disease?
Mitral regurgitation murmur (systolic murmur at apex)
How many patients have Mitral regurgitation after acute Mitral infarction?
Up to 60%
What is angina pectoris caused by?
Reduced O2 delivery to a section of the myocardium
What is angina pectoris felt as?
Heaviness, burning or aching pain in the chest +/- left arm
In terms of angina pectoris women have what kind of symptoms?
Generalized symptoms
What might angina pectoris possibly be caused by? (Besides O2 delivery)
Coronary spasm
What is stable angina a result of?
Stable plaque
What can stable angina be described as in terms of pain?
Predictable, regular chest pain
What the solution for stable angina?
Rest or nitroglycerine
How does unstable angina pain compare to stable angina? And how predictable is it?
More intense/ painful and not predictable
What is the solution for unstable angina?
May require immediate intervention
What does Myocardial infarctions lead to?
MI »_space; Arrhythmias (VT, VF)»_space; Asystole
When someone experiences MI what is immediately needed?
CPR and Defibrillation
In terms of Cardiac arrest survival rates drops by how much every minute without a pulse?
10%
During Myocardial infarction, once the pulse is back, what do we do?
Thrombolytics and PCI or emergency bypass
What are two types of Myocardial infarctions?
- NSTEMI
- STEMI
What is NSTEMI?
Zone of ischemia with small zone of cell death
In terms if NSTEMI it usually affects which area?
Subendocardial
What does the ST segment look in terms of NSTEMI?
Depressed
What is STEMI in terms of Myocardial infarction?
Transmural, which means through the whole thickness of the myocardium
from Endo to epi
What does the ST segment look like in terms of STEMI?
Elevated
What does these images represent from top down?
- Normal
- ST depression
- Infarct
What does ST depression indicate?
Ischemia
What does ST elevation represent?
Infarction
During MI where does arrhythmias originate?
In the ventricle
In terms of MI, what kind of heart blocks will we see?
AV block
If we see a new LBBB on an ECG what might this mean?
MI
In terms of MI what does Q waves indicate on the ECG?
Old MI (necrotic tissue)
In terms of MI, what does peaked T waves indicate?
Acute MI
In terms of MI, what does reversed T waves indicate on a ECG?
Chronic ischemia
What are some treatment options for ischemic heart disease? 6
- Smoking adjustment
- Diet
- Exercise
- Stress management
- Weight loss
- BP reduction
What are some medications that can help assist with ischemic heart disease treatment? 4
- Pain relief meds
- Anticoagulation
- Beta blockers
- Calcium channel blockers
What kind of pain relief meds does someone take for ischemic heart disease medication?
Nitroglycerine
What kind of anticoagulation medication does someone take for ischemic heart medicine? 2
- Plavix
- Warfarin/ coumadin
What are somethings we can look at to help diagnose ischemic heart disease? 6
- ECG
- Stress test
- Echo
- MIBI (Nuclear) stress test
- Cardiac CT or MRI
- Acute phase of MI requires blood work with enzymes
What is the gold standard for diagnosis for IHD?
Coronary angiogram
What is a stress test?
Exercise or pharmacological
How can we detect ischemic heart disease with Cardiac CT or MRI?
Perfusion defects
How can we diagnose Ischemic heart disease with the Acute phase of MI blood work and enzymes?
Certain blood and enzymes are released with myocardium injury occurs such as
1. Creatine kinase myocardial band
2. Troponin C (C- cardiac)
What are four MI differential diagnosis tools? (Signs we see)
- Aortic dissection
- Tension pneumothorax
- Pericardial disease
- Pleural effusion
What is the goal of Myocardial infarction management?
To restore normal coronary blood flow and save the myocardium
What are somethings we can do for MI management? 3
- Cath lab - Angioplasty
- Surgical
- Lifestyle changes
What are some surgical paths for MI management?
- Coronary artery bypass graft (CABG)
- Other
What does this image demonstrate?
Coronary angiography
What does this image demonstrate?
Coronary artery bypass graft
What is the role of echo in terms of ischemic heart disease? 2
- Assess for Wall motion and thickening
- Assess for regional wall thinning of affected wall segments
What is regional wall thinning of affected wall segments caused by?
Scarring and fibrosis over time
What does regional wall thinning of affected wall segments look like sonographically?
Increased echogenicity
Wall thickness with acute MI will look how?
Normal
What is sigmoid septum?
Basal septal focal hypertrophy
In terms of sigmoid septum, myocardial disarray may be related to what?
Reduced perfusion in that segment which caused it to thicken
What is the prognosis for sigmoid septum?
Increased risk for adverse cardiac events
What demographic is sigmoid septum more prominent in? 2
- Diabetics
- Elderly
What are some post MI complications? 7
- Secondary MR
- Thrombus formation
- Aneurysms
- Dressler’s syndrome and post MI pericarditis
- Acquired VSD
- CHF
- Ventricular arrhythmia
What is papillary muscle dysfunction?
Ischemia of papillary muscle segment
What does papillary muscle dysfunction cause?
Improper contraction of the segment and the pap muscle
What does papillary muscle dysfunction affect? and what does it lead too?
MV function leading to eccentric regurgitation
In terms of Papillary muscle dysfunction, ruptures are more common with what?
Inferior MI
Papillary muscle dysfunction may also occur where?
In right heart and TV
LV thrombus is what? Where is it usually located?
Echodense mass usually in apex
How does LV thrombus present? 2
- Protruding vs mural
- Mobile vs. Sessile
What kind of view visualization is required for LV thrombus?
2 view visualization
How are aneurysms grouped?
Either true or pseudo aneurysms
How common are Aneurysms?
Rare
What may line aneurysm?
Thrombus
Thrombus that lines aneurysm may cause what?
Systemic emboli
In terms of aneurysms, patients may present with what?
Continuing angina
What does these images represent?
True aneurysm vs Pseudo aneurysm
What does a pseudo aneurysm look like? 3
- Narrow neck
- Wall rupture
- Filled with thrombus
What does a true Aneurysm look like? 5
- Thin walls (<5mm)
- 80% at apex
- Wide neck
- All 3 wall layers present
- May leak into pericardium
When does Acute pericarditis POST MI occur?
1-4 days post MI
How many people are affected by acute pericarditis post MI?
25% of patients
What are 3 main features of acute pericarditis?
- Fever
- Pleuritic pain
- Pericardial effusion
In terms of acute pericarditis post MI, how often do we see Tamponade?
Rare
How does the pericardium look like during acute pericarditis post MI?
Pericardium may look bright over ABD wall motion area
What is pericarditis post MI related to?
Related to autoimmune response to necrosis
What is Dressler’s syndrome?
Delayed pericarditis
When does Dressler’s syndrome occur?
1-8 weeks post MI
How many people are affected by Dressler’s syndrome?
1-3% of patients (rare)
What is Dressler’s syndrome related to?
Autoimmune response to necrosis
What are some of the signs and symptoms of Dressler’s syndrome?
Same as pericarditis
What is VSD or Wall rupture due to in terms of MI?
Rupture of interventricular septum
What does VSD or Wall rupture due to MI sound like?2
- Loud systolic murmur, left sternal border
- Thrill
How does VSD or wall rupture due to MI move in the heart?
- High velocity flow across septum
- Flow into pericardium for wall rupture
What is the pathophysiology of VSD/ Wall rupture: post MI? 3
- MI damages the wall
- Shunt occurs
- Can leak into pericardium
What are some non IHD chest pain causes? 2
- Myocarditis
- Takotsubo cardiomyopathy (TTC)
What is myocarditis?
Inflammation of the myocardium resulting in myocardial damage
What is the pathophysiology of myocarditis? 4
- Myocardial infiltration produces toxin
- Autoimmune response
- Myocardial degeneration/ necrosis
- May cause heart failure
What are some signs and symptoms of myocarditis? 1, 6
- Infection symptoms
- Chest pain
- SOB
- Fatigue
- Arrthymia
- Asymptomatic
What are some echo findings for myocarditis? 3,5
- Dilated or hypertrophied ventricles
- LV dysnfunction
- RWMA
- Possible valvular issues
- Possible diastolic dysfunction
What are the criteria for TTC? 6
What is Takotsubo cardiomyopathy (TTC)?
Acute, transient or reversible LV dysfunction in the absence of obstructive CAD
What is TTC named after?
Japanese octopus trap
What does TTC mimic?
ACS
What is TTC triggered by?
Stress
Which demographic of people are affected by TTC?
Post menopausal women
How does TTC appear?
Transient, normal on F/U
What are four tips for IHD scans?
- Make sure you are on axis to see the RWMA
- Sweep
- Focus set
- Step out of the box (sometimes a new window is needed, or maybe a colour map)
