Slow Breathing and Breathing Meditations for Health

I read about a machine that you can pay a lot if money for, which helps lower your blood pressure by a breathing technique. I learned this Yoga breathing technique which does the same thing. Breath in, (through nose) half way..12345, hold...12345, breath in rest of way...12345, hold..1-5, Breath out half way through lips, 1-5, hold...1-5, finish emptying lungs as slowly as possible through pursed lips. Do 8 rounds of this. 8 is the Chinese lucky number. It is also the symbol for infinity when turned sideways. The object is to take longer on the exhale than on the inhale. I find that I can lower my BP quite a bit with this method.