What factor primarily determines the longevity of a cardiac device?

The longevity of a cardiac device is primarily influenced by the impedance and output characteristics. Impedance refers to the resistance the device encounters in the body, which can affect battery life and performance. Higher impedance can lead to increased energy consumption, potentially shortening the lifespan of the device.

Output settings determine how much energy the device uses to deliver pacing impulses to the heart. If the output is set too high, it can drain the battery more quickly. Therefore, managing impedance and optimizing the output are crucial for maximizing the operational lifespan of cardiac devices.

In contrast, while the rate of implantation, material of the leads, and surgeon experience may play roles in the overall success and functionality of the device, they do not directly dictate how long the device will last. The physical attributes of the device itself in relation to its operational demands primarily govern its longevity.