Which of the following most commonly can cause PAH? (LQ)
|C||Sickle cell disease|
|D||G6 PD deficiency|
Sickle cell disease
1). Pulmonary hypertension elevation of mean pulmonary artery pressure to >25 mm Hg at rest, or >30 mm Hg with exercise.
2). WHO has defined PAH to be present when a systolic pulmonary artery pressure is >40 mm Hg, which corresponds to tricuspid regurgitation on a Doppler echo cardiogram of 3-3.5 m/sec.
Pulmonary hypertension is primary or secondary in origin.
a. Primary pulmonary hypertension (PPH) is Idiopathic. Basic abnormality in gene lies in: Bone morphogenic proteinreceptor II (BMPR II)
b. Secondary pulmonary hypertension
Causes and mechanism of secondary PAH
Table: Mechanisms of pulmonary hypertension and examples of corresponding clinical conditions.
Reduction in cross-sectional area of pulmonary arterial bed
Hypoxia from any cause (chronic lung disease, sleep-disordered breathing, etc)
2). Loss of vessels:
b. Interstitial lung disease
3). Obstruction of vessels
a. Pulmonary embolism (thromboemboli, tumor emboli, etc)
c. Sickle cell disease
4). Narrowing of vessels
Secondary structural changes due to pulmonary hypertension
5). Increased pulmonary venous pressure
a. Constrictive pericarditis
b. LVF or reduced compliance
c. Mitral stenosis
6). Increased pulmonary blood flow:
Congenital left-to-right intracardiac shunts
7). Increased blood viscosity: