The test has been thought to provoke vasovagal syncope by allowing venous pooling and decreased return to the heart, thus triggering the Bezold-Jarisch mechanism (1).

• 该试验被认为通过导致静脉淤积并减少回心血量，因此触发Bezold-Jarisch机制，从而诱发血管迷走性晕厥。