True or False: Capture is a function of amplitude and polarization.

The correct understanding here lies in the nature of capture in pacing. Capture refers to the ability of the cardiac pacemaker to successfully depolarize the heart muscle in response to the electrical pulse it delivers. This requires certain conditions to be met, but it is not a function of amplitude and polarization in the straightforward sense suggested.

While you might consider that amplitude (or output voltage) can influence capture—higher amplitudes can indeed improve the likelihood of capture—the relationship is not solely based on amplitude and polarization. Capture mainly depends on factors such as the threshold for depolarization of myocardial tissue, the timing of the pacing pulse in relation to the cardiac cycle, and the integrity of the lead and surrounding tissue.

Therefore, saying that capture is a function of amplitude and polarization oversimplifies the complexities involved in pacing and capture initiation. It's a more multifaceted process than simply being dependent on these two factors. As such, the statement is false.