Regarding pulse width, what must it achieve for effective myocardial capture?

For effective myocardial capture, the pulse width must be long enough to ensure that depolarization occurs throughout the myocardial tissue. The heart muscle relies on electrical stimulation to contract, and the pulse width determines the duration of the electrical impulse delivered to the myocardium. If the pulse width is too short, the delivered energy may not be sufficient to stimulate all the necessary myocardial cells, potentially leading to ineffective capture.

A pulse width that is adequately extended allows the depolarization wave to propagate through the cells. This ensures that all the myocardial cells that need to respond to the pacing stimulus do so, thereby facilitating synchronous contraction of the heart muscle. Effective myocardial capture is essential for maintaining proper heart rhythm and function, especially in patients relying on pacemakers.

As such, ensuring that the pulse width is long enough for depolarization to disperse throughout the myocardial tissue is key to achieving effective pacing.