Pulmonary HTN updates..HIV and pulmonary HTN

 An association between HIV infection and pulmonary arterial hypertension was first reported in 1991.
- ► In population studies in which ECHO was used to estimate PA pressure, the incidence of PH ~0.5 % among patients with HIV infection
- ► a rate 6 to 12 times as high as in the general population.
- ► prevalence has not changed since 1991 despite the introduction of HAART
 The occurrence of pulmonary arterial hypertension is independent of the CD4 cell count, but it appears to be related to the duration of HIV infection.
 Many of these patients also have foreign-body emboli as a result of the use of intravenous drugs or portal hypertension due to a concomitant infection with hepatitis B or C.
 Still under discussion if HIV does directly infect endothelial cells, the mechanism of pulmonary hypertension in HIV infection is unclear.
 Postulated mechanism of HIV proteins like Envelope glycoprotein-120(Env), transactivator of transcription (Tat) and HIV negative factor (Nef).

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The pressure volume loop...

In the pressure-volume loop below, cardiac work is best represented by: the area of the curve the slope of the line from points C to D the distance of the line from points C to D the slope of a line from points A to D .. .. ... .... ... .... .... .... In the pressure-volume loop below, cardiac work is best represented by: the area of the curve Cardiac work is the product of pressure and volume and is linearly related to myocardial oxygen consumption. Cardiac work is best represented by the area of the curve of a pressure-volume loop.

Anaphylaxis updates part 2- Empty Ventricle Syndrome

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