A 49-year-old man with Marfan syndrome presents with progressive exertional dyspnea. Vital signs show BP 160/45 mmHg, HR 92 bpm, RR 18, and SpO2 98% on room air. Physical examination reveals head bobbing, bounding pulses, and a high-pitched early diastolic decrescendo murmur at the left sternal border. Transthoracic echocardiography demonstrates aortic root dilation to 5.2 cm with severe aortic regurgitation. No peripheral edema is noted. Which hemodynamic change best explains these findings?
- A)Decreased stroke volume with narrow pulse pressure
- B)Marked decrease in preload from venodilation
- C)Increased pulse pressure due to increased stroke volumeGABARITO
- D)No change in left ventricular end diastolic volume
- E)Fixed obstruction to left ventricular outflow
Explicação
Increased pulse pressure due to increased stroke volume is correct. Chronic aortic regurgitation causes volume overload of the left ventricle, raising stroke volume and lowering diastolic pressure because blood runs back into the ventricle. This produces a wid... Ver explicação completa e trilha adaptativa →