Sam Messina, a student at the University of Alabama had the scare of his life when he almost died post sneezing After sneezing, Sam saw a blood clot that came out of his nostrils which caused a brain stroke. According to doctors, Sam suffered from Arteriovenous Malformation or AVM, a neurological condition that causes a tangle of the blood vessels that connect arteries and veins in the brain. This condition can be super rare, and if not treated can cause permanent brain damage or even death. , Health News, Times Now