We and other TENS machine providers state that one shouldn't use a TENS machine with a pacemaker. This is a precaution just in case the TENS machine stimulation affects the functioning of the pacemaker and provokes an irregular heart action.

Medical literature does not show this having been tested (or experienced before). There is nothing in the literature to confirm this might be a problem, but we nevertheless suggest if you have a pacemaker and want to use TENS machine, that you contact your consultant cardiologist for his/her advice. Your cardiologist may wish to set up a TENS machine for you and monitor your heart tracing to assess your suitability for using TENS machine on a regular basis.
In respect of other heart conditions:

a. If you are suffering with chronic heart failure then you should consult your medical advisor for permission to use TENS machine.

b. If you suffer with a heart murmur again please consult your cardiologist for advice before using TENS machine.

c. While TENS machine is used for angina pain, especially in Europe, here in the UK we would recommend that you consult your medical advisor first before using TENS machine.

d. If you have had a recent myocardial infarction (heart attack/coronary thrombosis) especially if there was any a serious heart rhythm disturbances at the time or even a cardiac arrest, then you must seek advice from you Cardiologist or Specialist Cardiac Nurse before you use TENS machine.