What is the difference between severe pulmonary hypertension and raised jugular venous pressure? do they always coincide?

2 Different Issues: Pulmonary hypertension refers to increased blood pressures in the arteries from the right heart to the lung arterioles (arteriole size/degree-of-constriction vs. Blood flow volume determines the mean pressure). The jugular veins carry blood from the head to the superior vena cava ; right heart. Depending on several variables, either one could be elevated, normal or low while the other is not.

Difficult to discern: The real test called jvp was designed to determine presence of heart failure or fluid overload. The presence of high pressure against which the right ventricle has to work in pah causes the exaggerated bulging back of the tricuspid in rv systole and also causes jvp. Tricuspid stenosis thus would do the same thing.