Overheard--couldn't help it

When people talk on their cell phones in public, you can often hear everything--but only one side. It's a little different when they are sitting at a table across the room at the coffee shop and you hear one side of a 3-way. This guy was so loud I finally whispered about it to Computer Guy who is always reading at the table next to me. And it was pretty graphic--apparently he was a doctor. Couldn't figure out who the two women were, because I couldn't hear them--or they never had a chance to say anything. The longer I listened, the more familiar his voice became. Finally, it dawned on me. He was my cardiologist.