Final answer:
Factors affecting stroke volume include myocardial contractility, preload, and afterload. These contribute to the heart's pumping efficiency and the volume of blood pumped per beat.
Step-by-step explanation:
The nurse knows that factors that affect stroke volume include:
- Myocardial contractility
- Preload
- Afterload
Heart rate is a primary factor affecting cardiac output but not directly influencing stroke volume. Ventricular automaticity involves the rhythm of heart contractions but does not directly impact stroke volume. Stroke volume (SV) is ultimately dependent upon the difference between end-diastolic volume (EDV) and end-systolic volume (ESV). Preload is related to ventricular filling and EDV, whereas contractility refers to the force of the heart's contractions. Afterload is the resistance the ventricles overcome to circulate blood. These elements work in concert to influence the amount of blood the heart pumps with each beat.