Understanding the Heart as an Intermittent Pump

This excerpt encourages viewing the heart as a mechanical pump, similar to how a mechanic examines a machine. It contrasts this perspective with the common clinical description of a "weak" or "strong" heart, suggesting a need for more objective evaluation of its function. The text emphasizes that the heart is an intermittent pump, not a continuous one. It introduces the terms systole for the heart's contraction or pumping phase and diastole for its relaxation or non-pumping phase. This cycle of pumping and stopping is referred to as the cardiac cycle.