Cardio - Mechanisms of Disease - Cardiovascular Imaging; EKGs Flashcards
What imaging method acts as a preliminary test to evaluate the size of the heart’s chambers (cardiac silhouette) along with any pulmonary pathology resulting from heart disease?
Cardiac radiography
(NOTE: not useful in making diagnoses of histopathologic disease)
Cardiac radiography acts as a preliminary test to evaluate the _______ of the heart’s chambers (cardiac silhouette) along with any _______ pathology resulting from heart disease.
Cardiac radiography acts as a preliminary test to evaluate the size of the heart’s chambers (cardiac silhouette) along with any pulmonary pathology resulting from heart disease.
Cardiomegaly is defined as diameter of the heart at its widest point being what size?
> 50% of the cardiothoracic (CT) distance
If the pulmonary veins are engorged and visible in the upper part of the chest on CXR, this is called ___________ of vessels.
If the pulmonary veins are engorged and visible in the upper part of the chest on CXR, this is called cephalization of vessels.
Why is mitral stenosis associated with a bifid (‘notched’) P wave?
Subsequent left atrial enlargement leads to differential contraction between the left and right atria
How should the left atrium appear on CXR?
Concave
(a bulging left atrium indicates mitral stenosis or some other cause of left atrial enlargement)
True/False.
Stress testing is for screening like a CXR.
False.
Stress testing is not used for screening like a CXR (used for pts with suspected symptoms of coronary artery disease (CAD) to assess how different areas of the heart are being perfused. This is not a screening test because of its low specificity).
If a patient with S/Sy of coronary artery disease has an abnormal EKG, what should happen next?
Scintigraphy with radioisotope
If a patient with S/Sy of coronary artery disease has a normal EKG and can exercise, what should happen next?
The Bruce protocol treadmill test
If a patient with S/Sy of coronary artery disease has a normal EKG and cannot exercise, ability to tolerate what medication should be assessed?
Adenosine
If a patient with S/Sy of coronary artery disease has a normal EKG / cannot exercise / cannot tolerate adenosine, what should be done next?
A stress echo with dobutamine
(or PET scan)
What is a positive test stress result on EKG?
ST segment depression (1 mm) during exercise or in the recovery period
(reversibility on scintigraphic study)
What is a positive test stress result on scintigraphy?
Reversibility
What is a negative test stress result on scintigraphy?
NO reversibility
(the vessel that is not perfused during stress/exercise is still not perfused upon rest → indicative of an old infarction and thus a negative stress test result)
What imaging modality can evaluate the heart’s chamber size, wall thickness, wall motion, valves, pericardium, intracardiac tumors, thrombi, and vegetations?
Echocardiography
(using doppler ultrasound)
What are the two main viewing perspectives of echocardiography?
Transthoracic (TTE) or Transesophageal (TEE)
Which viewing perspective of echocardiography is more commonly used as it is less invasive?
Transthoracic
(as opposed to transesophageal)
What echocardiography method is useful in diagnosing cardiac valvular diseases?
Color-flow Doppler
A 28 year old man presents with a heart murmur that increases with Valsalva and decreases with squatting. S4 sound is noted at the apex, and he has some DOE (dyspnea on exertion) that’s worse during tennis. Family history is only positive for a cousin who died of sudden cardiac death of unkown cause at 34 years of age.
What is causing the murmur?
Hypertrophic cardiomyopathy
(due to a genetic disorder of sarcomere formation)
What is the characteristic finding in patients with hypertrophic cardiomyopathy?
A heart murmur that increases with Valsalva and decreases with squatting
What histopathology is characteristic of hypertrophic cardiomyopathy?
Myofibril disarray
What causes the murmur in hypertrophic cardiomyopathy?
Narrowing of the outflow tract –> increased turbulence
Is the murmur of hypertrophic cardiomyopathy diastolic or systolic?
Systolic
Where are 75% of myxomas found?
The left atrium
(attached to the interatrial septum)
True/False.
Mitral stenosis is associated with fluid in the alveolar space.
True.
What causes cephalization as seen on CXR?
Pulmonary venous congestion
What condition is often observed as the right ventricular wall being compressed, impeding preload?
Pericardial Effusion
A 57-year-old veteran with a below the- knee amputation (BKA), T2DM, and asthma presents with substernal chest discomfort while using his wheelchair. The symptoms started about one month ago. He has no symptoms at rest. You decide to evaluate him for coronary artery disease. The most appropriate test to order in this patient would be:
a) Treadmill stress test using standard Bruce protocol
b) Treadmill stress test with radionuclide augmentation
c) Pharmacologic stress test using adenosine
d) Dobutamine stress echo
d) Dobutamine stress echo
(he should not receive adenosine due to his risk of bronchospasm)
A 51-year-old very active man has been experiencing some mild substernal chest discomfort with exertion. His EKG shows LVH. What test should be performed next to evaluate this problem?
a) A standard treadmill test
b) A treadmill test using radionuclide augmentation (nuclear stress test)
c) Pharmacologic stress test using adenosine
d) A coronary angiogram
b) A treadmill test using radionuclide augmentation (nuclear stress test)
A 26-year-old woman was noted to have a II/VI systolic murmur at the left sternal border associated with some mild dyspnea on exertion. Which study should be performed in order to diagnose her condition?
a) An exercise stress test with radionuclide
b) A transthoracic echocardiogram (TTE)
c) A transesophageal echocardiogram (TEE)
d) A dobutamine stress echocardiogram
b) A transthoracic echocardiogram (TTE)
(coronary artery disease is not indicated here)
P waves should be upright in which leads?
Leads II, III, and aVF.
A wide QRS complex (>3 mm) is indicative of what?
A bundle branch block
The QT interval should be ____% the RR interval.
The QT interval should be <50% the RR interval.
What bundle branch block is associated with wide splitting?
Right BBB
What bundle branch block is associated with paradoxical splitting?
Left BBB
How does left bundle branch block manifest on EKG?
(prolonged at leads V1 and V6)
How does right bundle branch block manifest on EKG?
(QRS is prolonged at leads V1 and V6.)
What are the main effects of hyperkalemia on EKG?
Wide QRS + peaked T waves
True/False.
Hypercalcemia is an important cause of QT prolongation.
False.
Hypocalcemia is an important cause of QT prolongation.
What two EKG findings are shown here?
a) Ventricular tachycardia
b) Ventricular fibrillation
Hypocalcemia
(slowed heart rate)
Hyperkalemia
Name three risk factors for atrial fibrillation.
Previous MI;
heart failure;
hypertension
Cocaine, exercising, ischemia, and fever can all cause what EKG finding?
Sinus tachycardia
Athleticism, beta-blockers, and old age/sick sinus syndrome can all cause what EKG finding?
Sinus bradycardia
Why might an EKG show very low voltage complexes?
Due to pericardial fluid or other obstructive substances
How can you determine a patient’s expected sinus node maximum firing rate?
220 – age
Very tall QRS complexes are indicative of what?
Left ventricular hypertrophy
Bradycardia: HR is < ___ beats per min
Tachycardia: HR is ≥ ___ beats per min
Bradycardia: HR is < 60 beats per min
Tachycardia: HR is ≥ 100 beats per min
A 34 year old patient has a maximum sinus node firing rate of ______ BPM.
A 34 year old patient has a maximum sinus node firing rate of 186 BPM.
(220 - age)
Regular sinus rhythm is defined as what?
Upright P wave followed by QRS complex
Left atrial enlargement presents as what on EKG?
Notched P wave
Right atrial abnormalities present how on EKG?
Large, tall P waves
How does bi-atrial enlargement present on EKG?
(1) Tall or peaked P wave (indicating RAA)
AND
(2) negative deflection (indicating LAA)
How does hypokalemia present on EKG?
Flat T waves
How does hyperkalemia present on EKG?
Tall, peaked T waves
How do T waves present on EKG during ischemia?
Inverted
How do subendocardial injuries present on EKG?
Depressed ST segment
How do epicardial injuries present on EKG?
Elevated ST segment
How do transmural injuries present on EKG?
Elevated ST segment
Atrial fibrillation, atrial flutter, and supravetricular tachycardia are all examples of what?
Supraventricular rhythyms
How does acute pericarditis present on EKG?
Diffuse ST elevation
(as well as PR segment depression)
True/False.
A new left-bundle-branch-block in the setting of chest pain is a surrogate for STEMI.
True.
Hypocalcemia leads to a(n) __________ QT interval.
Hypercalcemia leads to a(n) __________ QT interval.
Hypocalcemia leads to an increased QT interval.
Hypercalcemia leads to a decreased QT interval.
