A 34 year old woman develops fatigue, dyspnea on exertion, and bounding peripheral pulses several months after creation of a large arteriovenous fistula for hemodialysis access. Skin is warm and blood pressure is 132/48 mm Hg. Cardiac output is increased on hemodynamic testing. Which of the following best explains her symptoms?
- A)Increased systemic vascular resistance causing pressure overload
- B)Obstruction of left ventricular outflow tract
- C)Reduced venous return due to preload depletion
- D)High output state from decreased systemic vascular resistanceGABARITO
- E)Fixed reduction in diastolic filling due to pericardial scarring
Explicação
High output state from decreased systemic vascular resistance is correct. Large arteriovenous shunts lower systemic vascular resistance and increase venous return, forcing the heart to maintain an abnormally high cardiac output. Despite high output, tissues ca... Ver explicação completa e trilha adaptativa →