How are muscle cells categorized in the heart?

Muscle cells in the heart are categorized into two distinct types: mechanical working cells and electrical cells. The mechanical working cells, primarily composed of myocytes, are responsible for the contraction of the heart muscles, facilitating blood pumping throughout the circulatory system. These cells contain actin and myosin filaments, which allow them to contract and generate force.

The electrical cells, including pacemaker cells such as those found in the sinoatrial (SA) node, are crucial for initiating and conducting the electrical impulses that trigger heart contractions. These cells help regulate the heart's rhythm and ensure coordinated contractions, allowing for effective blood circulation.

This classification highlights the specialized functions of heart muscle cells, emphasizing the distinction between those that generate mechanical force and those that control the timing and rhythm of cardiac activity. Cardiovascular perfusionists must understand this categorization to manage heart function effectively during procedures that involve cardiopulmonary bypass or other interventions.