Breathing and heartbeat / tantric techniques

Does anyone have experience using breathing techniques to slow heartbeat and lower bp? I have seen videos of tantric techniques where two men placed their hands on each other's bare chests and slowed their breathing by syncing their inhalation. I tried doing it to myself (left hand over heart and right over abdomen). It kinda works but because I am doing it to myself I loose concentration. I am attracted to the caring / comfort / literal hands-on approach to medicine. I think that's why I miss old-time exams where the doctor would touch my bare skin when examining me. The exam rooms always seemed too cool - maybe because I was in my underwear - and I remember the sensation of a cold stethoscope held in a warm palm against my chilled skin.

Most of the videos I have seen are the prelude to something more. The men are usually nude or wrapped in a sarong, massage oil appears and that leads to intimate sexual contact. I am thinking of more of an exam scenario, where after the exam the doc suggests a breathing session with him, where he shows me how to better control my heartbeat and bp through this technique. Thoughts?

Many years ago I met a yoga teacher who taught me to control my emotions. She controlled his heartbeat with her breathing