Final answer:
Aortic stenosis is the condition in which the aortic valve narrows and obstructs blood flow, requiring the heart to work harder and potentially weakening it over time. It becomes more prevalent with age and may demand urgent surgical treatment if acute complications occur.
Step-by-step explanation:
The condition that occurs when the aortic valve narrows, partially obstructing blood flow across the valve is known as aortic stenosis. This condition causes the heart valves to become rigid, and they may calcify over time, losing flexibility. This impairs the normal functioning of the heart and forces it to work harder to pump blood through the narrowed valve, which can lead to weakening of the heart muscle.
Aortic stenosis is especially common among the elderly, affecting approximately 2% of people over the age of 65 and increasing to about 4% in those over 85. In certain acute cases, as a consequence of complications like the tearing of chordae tendineae or death of the papillary muscle during a myocardial infarction (heart attack), the patient's condition may rapidly worsen, necessitating immediate surgical intervention.