Final answer:
The symptoms of widened pulse pressure, diastolic decrescendo murmur at LSB, and water-hammer pulse are characteristic of aortic regurgitation, a condition where blood flows back into the left ventricle from the aorta during diastole.
Step-by-step explanation:
The symptoms presented in this question, such as widened pulse pressure, diastolic decrescendo murmur at the left sternal border (LSB), and water-hammer pulse, are indicative of aortic regurgitation. Aortic regurgitation is characterized by the backflow of blood from the aorta into the left ventricle during diastole, leading to these specific clinical findings. To rule out other conditions, consider that aortic stenosis typically presents with a systolic murmur, mitral stenosis with a diastolic rumbling murmur, and mitral regurgitation with a holosystolic murmur. Thus, the correct answer to the question is b) Aortic regurgitation.
During the early phase of ventricular diastole, also known as the isovolumetric ventricular relaxation phase, semilunar valves close to prevent backflow into the heart. This closure contributes to the second heart sound. In aortic regurgitation, the faulty aortic semilunar valve leads to a distinct diastolic decrescendo murmur.