First Degree Atrial Ventricular Block

FAA changed the acceptable PR interval to less than 0.30 seconds and removed the reference to the individual's age. Senator Ron Johnson wrote a letter to the FAA about this change in guidance for aviation medical examiners. In their response, they basically said that first degree AV blocks between 200 and 300 milliseconds do not require cardiac workup and can be followed as a normal variant. This contradicts what was done in an extensive 2009 Harvard study over a 20 to 30 year period on a population called the Framingham population.