Which type of test involves amplitude decrement?

The amplitude decrement is a key feature of the ventricular threshold test, which is conducted to determine the minimum amount of electrical energy required to consistently capture the ventricle during pacing. This test is crucial because it assesses the responsiveness of the heart to pacing stimuli, helping clinicians adjust the pacing output settings and ensure effective cardiac stimulation.

During this test, the pacing output is gradually decreased in amplitude until capture is lost, allowing the clinician to identify the threshold at which the heart fails to respond to the pacing pulse. This information is essential for programming cardiac devices like pacemakers, as it ensures that the device delivers adequate stimulation to maintain proper heart rhythm.

In contrast, the other types of tests mentioned do not specifically involve amplitude decrement. While diagnostic pacing tests and electrophysiological studies may involve pacing and assessment of heart function, they do not necessarily focus on systematically determining a diminishing amplitude until a loss of capture occurs. Cardiac output measurement typically involves hemodynamic assessments rather than the stimulation thresholds specific to the heart's pacing response.