What's the actual safe level of drinking for a man with cardiovascular risk factors?

There is no universal threshold, but there is a framework. For men with established cardiovascular disease, prior heart attack, stent, bypass, known coronary artery calcium above 100, the evidence supports the most conservative stance: the combination of AFib risk, blood pressure effect, and sleep disruption creates a cardiovascular tax with no offsetting cardioprotective benefit, since Mendelian randomization removed that benefit from the equation. For these men, I recommend alcohol reduction as a cardiovascular intervention, not a lifestyle preference.

For men without established CVD, the calibration is individualized. Meaningful modifiers include: family history of AFib, existing blood pressure above 130/80, current sleep architecture disruption, elevated hs-CRP, and how honestly one counts units consumed. The clinical threshold where direct harm (beyond AFib risk) becomes substantial is 14 units per week for men. One standard drink is approximately one unit. Two glasses of wine per night is 35 units per week, 2.5 times the threshold. The arithmetic often surprises men who describe themselves as moderate drinkers. (GBD 2016 Alcohol Collaborators, Lancet, 201831310-2/fulltext))

Cardiologist's calibrated position, Solid (1) for the 14 unit/week threshold as the boundary of meaningful population-level cardiovascular harm. Individualized risk factors modify the interpretation substantially.

What to do: Count your actual weekly units using the correct math: a 5 oz glass of 13% wine is approximately 2.5 units, not 1. If your number is above 14 per week, you are in a range where the cardiovascular case for reduction is clear.

For the full picture, read The Bourbon Collector's Honest Reckoning.