American Board of Surgery Qualifying Exam (ABS QE) Practice Test

How does aging typically affect the myocardial function?

1. The myocardium becomes more compliant

2. Contractility is reduced and stiffness increases

3. Filling pressures decrease significantly

4. Arrhythmias become less common

The correct answer is: Contractility is reduced and stiffness increases

As individuals age, the myocardial function undergoes several physiological changes. One prominent effect of aging is a reduction in contractility, which refers to the heart muscle's ability to contract effectively. This decline in contractility is often associated with structural changes, such as ventricular hypertrophy and fibrotic changes, leading to decreased pumping efficiency. Additionally, stiffness in the myocardium tends to increase with age. This increased stiffness makes it harder for the heart to relax fully, leading to higher diastolic pressures during filling. Consequently, the overall effect is a compromised ability to handle the demands placed on the heart, particularly under stress or during increased physical activity, which can manifest as heart failure with preserved ejection fraction (HFpEF) in many elderly patients. The other options suggest changes that typically do not occur with aging. The myocardium becoming more compliant is contrary to the increased stiffness observed. A significant decrease in filling pressures is also not common, as aging generally leads to higher rather than lower filling pressures due to the aforementioned stiffness. Lastly, the incidence of arrhythmias tends to increase with age due to various factors, including changes in the conduction system of the heart, not decrease. Thus, the correct understanding of these aging effects aligns with the recognized