Total bullshiite
Normal PR is .12-.2 and has been for a long time — as cited here, found in a quick search. Well established, common knowledge
https://www.nottingham.ac.uk/nursing/practice/resources/cardiology/function/normal_duration.php#:~:text=The%20P%2DR%20Interval,5%20small%20squares%20in%20duration.
—- This is straight from the FAA’s web site for aeromedical examiners: Notice it’s an “update from Oct ‘2022, and see the max interval is up to 300 ms, not 200 as it should be. And that’s not the only standard that has been relaxed, there’s a long list.
Normal Variants (Updated 10/26/2022) The following common ECG findings are considered normal variants and are not cause for deferment unless the airman is symptomatic or there are other concerns. Airmen who have these findings may be certified, if otherwise qualified: • Early repolarization • Ectopic atrial rhythm • First-degree AV (atrioventricular) block with PR interval less than 300 ms (0.30 sec). • Incomplete Right Bundle Branch Block (IRBBB) • Indeterminate axis • Intraventricular conduction delay (IVCD) • Left atrial abnormality • Left axis deviation, less than or equal to -30 degrees • Left ventricular hypertrophy by voltage criteria only • Low atrial rhythm • Low voltage in limb leads (May be a sign of obesity or hypothyroidism.) • Premature Atrial Contraction (PAC) – multiple, asymptomatic • Premature Ventricular Contraction (PVC) - single only; 2 or more on ECG require evaluation • Short QT – if no history of arrhythmia • Sinus arrhythmia • Sinus bradycardia. Up to age 49 if heart rate is >44; Age 50 and older if heart rate is >48 • Sinus tachycardia – heart rate < 110 • Wandering atrial pacemaker
All this directly from the FAA - copied and pasted.
https://www.faa.gov/ame_guide/media/Normal_Variants.pdf