Card Tamponade

Question 1

What layer of the pericardium is responsible for tamponade?

Answer 1

The two layers are the visceral and parietal segments. The parietal segment is non-compliant and so it is responsible for tamponade physiology

Question 1

How does right and left heart filling vary with inspiration?

Answer 1

Inspiration: decrease in intrathoracic pressure -> increased venous return to right heart -> decrease left heart filling (septal bounce towards LV) -> decrease in SBP

Question 2

How does right and left heart filling vary with expiration?

Answer 2

Expiration: increase in intrathoracic pressure -> decreased venous return to right heart -> increase in left heart filling (septal bowing towards RV) -> increase in SBP

Question 3

Why do you have a variation in right and left heart filling with respiration?

Answer 3

Due to ventricular interdependence

Question 4

When do you see chamber collapse in tamponade?

Answer 4

When the intrapericardial pressures equals or exceeds the intracardiac pressures

Question 5

Does the volume or rate of accumulation matter more in tamponade?

Answer 5

The rate of accumulation; in chronic tamponade, the parietal pericardium can stretch to accommodate more fluid

Question 6

Physical exam findings of cardiac tamponade

Answer 6

Tachycardia (increased SVR from increased sympathetic tone) + hypotension (decreased stroke volume) + pulsus paradoxus (10mmHg+ drop in SBP with inspiration)

Question 7

What is the diagnostic test of choice for tamponade?

Answer 7

TTE (accessible and accurate)

Question 8

What are some typical echo findings for tamponade?

Answer 8

Late diastolic RA collapse (RA pressures low in late diastole so pericardial pressures exceed it) + early diastolic RV collapse (RV pressures low in early diastole) + if RA collapse lasts for more than 1/3 of the cardiac cycle (early marker of tamponade) + IVC dilation + respiratory variation in mitral and tricuspid inflow velocities (mitral E-wave decreases >30% with inspiration or tricuspid E-wave decreases >60% with expiration)

Question 9

Normal CVP tracing and waves

Answer 9

a wave = RA contraction, x descent = RA relaxation, v wave = passive filling of RA during RV systole, y wave = passive RA emptying after TV opens

Question 10

CVP tracing and waves in tamponade

Answer 10

Will see a dominant x descent during ventricular systole and reduced or absent y-descent (passive RA emptying) since pressures are all equalized

Question 11

CVP tracing (normal and tamponade) image

Answer 11

See Excel

Question 12

What do you see with a PA catheter in tamponade?

Answer 12

Equalization of all chamber pressures during diastole

Question 13

What is the classic finding on CXR for tamponade?

Answer 13

“Water bottle” heart (only seen in chronic tamponade with large effusions); may see nothing if accumulation is acute

Question 14

Pericardiocentesis versus pericardial window outcome differences?

Answer 14

Higher risk of incomplete drainage and recurrence with pericardiocentesis compared to pericardial window

Question 15

What is the reason for pulsus paradoxus in tamponade?

Answer 15

Exaggerated ventricular interdependence

Question 16

What do we see in tamponade as pericardial pressures increase?

Answer 16

We see increases in diastolic filling pressures on both the right (CVP, RVEDP) and left sides (PCWP, LVEDP) leading to equalization of pressures

Question 17

What happens to your E/A waves with tamponade?

Answer 17

The E waves is decreased because the pressures are equalizing and you have less of a pressure gradient for early diastolic filling of the LV (hence the lack of a y-descent on the right side)

Question 18

When do you not see the classic echo findings of tamponade?

Answer 18

RA collapse in late diastole and RV collapse in early diastole can be masked in patients with significant pulmonary HTN or RV hypertrophy

Question 19

What is pericardial decompression syndrome?

Answer 19

Hemodynamic compromise that occurs within 48 hours of drainage of a pericardial effusion

Question 20

Why does pericardial decompression syndrome occur?

Answer 20

Rapid expansion of the right-sided chambers -> decreases left-sided filling and contributes to acute left-sided heart failure; rapid increase in preload and ventricular filling from surgical correction of pericardial effusions can unmask pre-existing LV and RV systolic dysfunction + stunning due to decreased myocardial perfusion may also play a role

Question 21

What is the mortality rate of pericardial decompression syndrome?

Answer 21

29%

Question 22

What is the treatment of pericardial decompression syndrome?

Answer 22

Early recognition and aggressive supportive care