Pulmonary Hypertension 

In morning report today we discussed the case of an elderly patient who presents with dyspnea. Specific points include an echocardiogram that showed a normal LV, with no significant diastolic dysfunction, but reported a very elevated RVSP (over 100). 

Given the absence of obvious left sided heart disease as the cause and suggestions of high right sided pressures, the diagnosis of pulmonary hypertension was raised. 

Approach to pulmonary hypertension

An anatomical approach is useful and from this come the 5 major categories of disease.

1. PAH (pulmonary  artery hypertension)

-idiopathic, hereditary ((bmpr2, alk (alk mutations, not the ones that cause cancer, can lead to PAH, and HHT))

-secondary to CTD (scleroderma more often CREST, anticentromere…whereas anti-scl70 is systemic, causes ILD), HIV, 

-hemoglobinopathies (ie sickle cell, anything with hemolysis leads to binding of NO that prevents vasodilation), drugs (amphetamines, cocaine, fen-phen)

1 prime: PVOD (pulmonary veno-occlusive disease)

PVOD vs PAH: one defining feature is that if PVOD receives PAH treatment, they will get significantly worse.

2. Cardiac: CHF, LV dysfunction, AS, MR, diastolic

3. Lung disease: Chronic hypoxemia eg COPD, OSA, hypoventilation syndrome or parenchymal lung disease eg ILD

4. CTEPH: treated with endarterectomy (surgery)

5. Miscellaneous: sarcoid, langerhan’s, splenectomy, mpd, glycogen storage diseases

Workup

History, physical 

-looking for consequences of and causes of pulmonary hypertension:

O/E

-Elevated JVP, CV, loud P2, palpable P2, RV heave, SOA, pulsatile liver.

PFT’s (also 6 minute walk test for prognostication, not diagnostic)

- looking for lung disease

- normal pft but isolated dlco would be hint to IPAH

ECHO

-Normal RVSP is 35

-RV dilatation, RV hypokinesis, pericard effusion

V/Q scan

-looking for CTEPH

-CT is good for acute, but not chronic. If V/Q positive, CT normal, then think of CTEPH

High res CT with contrast

-for parenchymal lung disease. Contrast is to help look for PE’s

Sleep study

BW: 

-CTD, HIV, Hgb electrophoresis etc.

Right heart catheterization

-mPAP > 25 with PCWP < 15

-Trans pulm grad is mPAP – PCWP  If > 12 then abnormal

Treatment considerations include:

- Oxygen 

- Diuretics 

- Anticoagulation (controversial)

Condition specific treatments include: 

For CTEPH: endarterectomy, Riociguat (recent NEJM link is here)

PAH: endothelin antagonist such as bosentan, vasodilators such as PDE5 inhibitors, IV epoprostenol

Lastly is transplant.

For more check out this BMJ review article on pulmonary hypertension, also where the above figure comes from.