This card is very confusing as written. According to AMBOSS (see below), LV preload is decreased in all forms of obstructive shock. PCWP is decreased in all forms of obstructive shock except cardiac tamponade, where it is paradoxically increased. Recommend specifying LV preload since that's what is relevant here, as well as making it explicit that LV preload is decreased in all cases. As far as the difference between cardiac tamponade and the others, I recommend either explaining in "Extra" (as I did in this note change), or creating separate card.

Copied from the AMBOSS page on obstructive shock:
Pathophysiology [6]
Common mechanism: obstruction of the heart or its great vessels → inability of the heart to circulate blood → ↓ CO → compensatory ↑ SVR

Pulmonary embolism or severe PAH
Obstructions of the pulmonary vasculature → ↓ PCWP → ↑ RV pressure → right heart failure
↑ RV pressure → ↑ pressure on LV by the RV → ↓ LV diastolic filling → ↓ CO
Right heart failure → ↓ LV preload → ↓ CO

Tension pneumothorax
↑ Intrathoracic pressure → ↓ venous return → ↓ preload → ↓ PCWP
↑ Intrathoracic pressure → ↓ LV diastolic filling → ↓ CO

Cardiac tamponade
↑ Pericardial pressure → ↑ RV pressure → ↓ RV diastolic filling → right heart failure
↑ Pericardial pressure → ↑ LV pressure → ↓ LV diastolic filling → ↓ CO
↑ LV pressure → ↑ PCWP → ↑ RV pressure
Right heart failure → ↓ LV preload → ↓ CO

Despite manifesting with high PCWP, many causes of obstructive shock (e.g., severe pulmonary hypertension, cardiac tamponade) are considered preload-dependent states. [6]

Elevation and equalization of pressures in all the cardiac chambers differentiate cardiac tamponade from other causes of obstructive shock.

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