SEM 2 Lab 2: Chest Xray And ECG

Question 1

Interpret

Answer 1

Note that ECG findings are non-specific. No single ECG finding is diagnostic for the above.

Pericarditis: Widespread concave ST elevation and PR depression throughout most of the limb leads (I, II, III, aVL, aVF) and precordial leads (V2-6). Reciprocal ST depression and PR elevation in lead aVR (± V1). Sinus tachycardia is also common in acute pericarditis due to pain and/or pericardial effusion https://litfl.com/pericarditis-ecg-library/ Endocarditis: widening PR interval, AV block, p mitrale, T-wave inversion, dysrhythmia https://litfl.com/infective-endocarditis/ Aortic stenosis: LV hypertrophy, often with secondary repolarization abnormalities. Left atrial enlargement and conduction abnormalities are also common, including left and right bundle branch block. The axis may be shifted leftward or rightward. Atrial fibrillation can also develop. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2861980/#:~:text=bilateral%20pleural%20effusions.-,Electrocardiography.,aVL%2C%20and%20V3%20through%20V6. Aortic regurgitation: LV hypertrophy with or without associated repolarization abnormalities. Left axis deviation may also be present. With early LV volume overload, there are prominent Q waves in leads I, aVL, and V3 through V6. As the disease progresses, the prominent initial forces decrease, but the total QRS amplitude increases Mitral regurgitation: Left atrial enlargement and atrial fibrillation are the most common ECG findings. Left ventricular enlargement is noted in approximately one-third of patients, and RV hypertrophy is observed in 15%. Mitral stenosis: The most common ECG finding is left atrial enlargement. Atrial fibrillation is also a common finding. Electrocardiographic evidence of RV hypertrophy occurs in individuals with pulmonary hypertension.

Question 2

Interpret

Answer 2

Myocarditis: Sinus tachycardia. QRS / QT prolongation. Diffuse T wave inversion. Ventricular arrhythmias. AV conduction defects. With inflammation of the adjacent pericardium, ECG features of pericarditis can also be seen (= myopericarditis) https://litfl.com/myocarditis-ecg-library/

Question 3

Interpret Endocarditis

Answer 3

Endocarditis: widening PR interval, AV block, p mitrale, T-wave inversion, dysrhythmia

https://litfl.com/infective-endocarditis/

Question 4

Interpet

Answer 4

CXR above shows septic pulmonary emboli – CXR features are generally non-specific but may show
- Peripheral, lower lob predominant infiltrative densities(unilateral or bilateral)
- Diffuse bilateral nodular densities, often poorly margined in varying stages of cavitation
- Nodules generally vary greatly in size (reflective of repeated episodes)
- May increase in number or change in appearance (size or degree of cavitation) on subsequent follow up images
https://emcrit.org/ibcc/endo/#when_to_suspect_endocarditis

Question 5

Interpret

Answer 5

CXR – Cardiomegaly. Interstitial and alveolar edema, fluid in fissures
12 lead - Afib with RVR. PVCs. Lateral T-wave inversion

Question 6

Interpret

Answer 6

Patients ECG above – Asymmetrical HCM. Voltage criteria met for LVH in precordial and limb leads. “Dagger Qs” in inferior and lateral leads.

https://litfl.com/dilated-cardiomyopathy-dcm-ecg-library/

Question 7

Interpret

Answer 7

CXR Interpretation​
Marked enlargement of the cardiac outline. This was due to pericardial effusion and is a good example of thewater bottle sign.​
ECG Interpretation​
Pericardial effusion. Low voltage in the limb leads. Electrical alternans. TWI and STD suggestive of global subendocardial ischemia.

The size of pericardial effusion doesn’t necessarily correlate with presence of tamponade: Rapid development of a small effusion may cause tamponade.
Gradual development of a large effusion may not cause tamponade.
Plain radiograph
Small pericardial effusions are often occult on plain film. Greater than 200 mL of pericardial fluid is usually required to become radiographically visible. Radiographic signs include:
there can be globular enlargement of the cardiac shadow giving awater bottle configuration
lateral CXR may show a vertical opaque line (pericardial fluid)separating a vertical lucent line directly behind the sternum (pericardial fat) anteriorly from a similar lucent vertical lucent line (epicardial fat) posteriorly; this is known as theOreo cookie sign5
widening of the subcarinal angle without other evidence of left atrial enlargement may be an indirect clue2

CT
The accepted thickness of a normal pericardium, measured on CT scans and on MR images, is often taken at 2 mm6,10and abnormal is considered >3-4 mm

Question 8

Interpret

Answer 8

• CXR Interpretation
• The right pulmonary artery is enlarged, with subtle oligemia in the right lung compared to the left. Westermark and Fleischner signs of pulmonary embolism
• ECG Interpretation
• Right heart strain showing tachycardia, new right bundle branch block, ST depressions in V1 - V4
•

Question 9

Interpret

Answer 9

CXR – prominence of pulmonary artery and right ventricle (with lateral films RV dilation abuts the sternum)

Question 10

Interpret

Answer 10

CXR- ICD and LVAD in good position
ECG – Monomorphic vtach