Your ICD does not pace your heart like a pacemaker. It does not continue to pace your heart at a fixed rate. A pacemaker recipient is either non dependent or dependent on pacemaker. With dependent pacing is all the time. With non dependent it can be set to pace at certain pacing if HR drops.

An ICD is a shocking and pulsing device. What you are talking about is the device can be set for a certain pulse rate and ICD will try to pulse you out of it. IF that pulsing does not work the ICD will shock you back to normal rhythm. The device can monitor and temporary make pulsing to correct heart rhythm but is not a device to continuous pace the heart like a pacemaker.

A shock is not a pacing. The ICD will charge and sent an electrical shock to your heart. It can be programmed to try to pace you out but that is temporary and if does not work will shock you.

Talk your your doctors, especially if you have a EP and they can explain more clearly the role of each. Many people only have ICD when they have tachycardia and or rhythm problem. Some only have pacemakers to keep being paced at certain levels two ways, one all the time at a certain rate, or kick in when HR gets below a certain rate. A pacemaker will never shock like an ICD.

So you can see the differences. My device is a dual device. It paces my heart at 70 beats a minute because my resting pulse rate would be in low 40s. My ICD is set to act if tachycardia at a certain rate occurs. It will try to pace me out first and if fails will shock me. It will not continually pace me if pacing does not bring me out of tachycardia, it will shock me.

Just had a lot of experience with these devices and on my 3rd one with another coming 1 year from now. I am monitored at Mayo Pace Clinic and my device records are sent to Mayo every 3 months or anytime an episodes
happens. I go into pace clinic once a year to check wires, and programming.