John is a 35-year-old nurse who had rheumatic fever as a child. He noticed a persistent tachycardia and light-headedness. Chest x-rays showed an enlarged left atrium and left ventricle. ECG analysis showed atrial fibrillation and mild pulmonary congestion. Cardiac evaluation resulted in the following information:
Cardiac output (CO) 3.4 L/min
Blood pressure (BP) 100/58 mm Hg
Left atrial pressure (LAP) 16 mm Hg
Right ventricular pressure (RVP) 44/8 mm Hg
Heart sounds revealed valvular regurgitation.
- Deduce which A-V valve is incompetent, thus allowing the regurgitation.
- Using anatomical terms, describe the location at which this valvular disorder could best be heard.
- Which heart sound would be pronounced and lengthened?
- If the other AV valve were incompetent instead of this one, would the CO, BP, LAP, and RVP be different? If so, how?
- What are the causes of the tachycardia, light-headedness, and mild pulmonary congestion?