1) This patient has a moderate pericardial effusion. Pericardial effusions are classified as small if they are <1 cm, moderate if they are 1-2 cm, and large if they are >2 cm. This can be measured at end diastole along the posterior wall of the LV.
The question now is: to tap or not to tap?
In this case we would not recommend pericardiocentesis at this time for the following reasons:
- We do not observe RA collapse during ventricular systole (i.e. when the RA should be filled). RA collapse for more than 1/3 of the cardiac cycle is almost 100% sensitive and specific for cardiac tamponade, and this is not seen in this patient.
- We also do not observe RV collapse during ventricular diastole in this patient. In early tamponade this will only be present during expiration (in a spontaneously breathing patient), but as intrapericardial pressures increase this may be present in inspiration as well. This sign is more sensitive and specific for cardiac tamponade than our trusty pulsus paradoxus measurement at the bedside.
- *NB: the above signs may not be present in patients with pulmonary hypertension, positive pressure ventilation or severe LV failure.
- This patient has a normal cardiac output as shown by the VTI measurement. With significant tamponade we should see reduced cardiac output.
- *NB: this patient does have a mildly dilated IVC (>2 cm), which is sensitive for cardiac tamponade. However, it is a non-specific finding, and should not be used as the sole determinant for tamponade. If they do not have a dilated IVC then it’s very unlikely that they have cardiac tamponade and you can rule it out, but if they do have a dilated IVC it does not mean you can rule in cardiac tamponade. You should look for other signs of tamponade.
Reference: Perez-Casares, et. al. Front Pediatr. 2017; 5: 79.
2) This patient has a prominent epicardial fat pad over his RA and RV. It is the isoechoic density that is well-seen over his RA and RV.
A and B are incorrect as we do not see features of these pathologies on these images, and D is incorrect as we see the RA is well filled during ventricular systole (also known as atrial diastole).