Probable mechanisms may include:
(1) increased intrathoracic pressure
(2) stretch and/or twist on the arterial wall
(3) defect in arterial wall structure
Conditions that may precede a dissection of a carotid or vertebral artery:
(1) hyperextension, rotation or torsion on the affected artery (see below)
(2) hereditary connective tissue disorder or other familial disorder
(3) recent infection
(4) risk factors for atherosclerotic disease such as elevated plasma homocysteine levels, cigarette smoking and/or hypercholesterolemia
(5) arteriopathy
Conditions associated with hyperextension, rotation or torsion on the affected artery:
(1) practicing yoga
(2) chiropractic cervical spine manipulation
(3) painting a ceiling
(4) coughing
(5) falling off a trampoline
(6) vomiting
(7) sneezing
(8) receipt of anesthesia
(9) cardiopulmonary resuscitation
(10) lifting a heavy object
(11) archery
(12) falls
(13) prolonged telephone calls
(14) roller coaster ride
(15) falling asleep with the head twisted
(16) car accident with whiplash injury
(17) doing push ups