Doctors crack Christmas card-iology conundrum

Ah, the festive season. A time for chocolate, booze, family, arguments, family arguments, Monopoly, and above-average incidence of myocardial infarction.
It’s well-known among the general population as well as the medical establishment that in locations where Christmas is widely observed, the late December period marks the annual peak for MI.
The reasons aren’t clearly understood, but you can easily write your own jokes to explain it.
‘If you’d dealt with my aunt after seven G&Ts you’d find any excuse to escape to an ED, hur hur hur’. Et cetera.