Pulmonary HTN Flashcards
epidemiology for PAH
sex
age
when does dx happen?
young females - 3rd or 4th decade
mean age at dx - 36 (any age possible)
diagnosis often delayed - non specific presenting symptoms
what is the median survival after diagnosis of PAH
3-5 years
not good
what is the definition of PAH? in terms of numbers
Mean PAP > 25 mm Hg at rest
PAP > 30 mm Hg w/ exercise
Mean PCWP and LVEDP less than 15 mm Hg
why do we include a mean PCWP and LVEDP of less than 15 mm Hg in our definition of PAH?
to rule out L heart failure
these are the gold standard measurements for diagnosing L heart failure, i.e. seeing an increase in LV and LA pressure
what is the definition of Primary Pulmonary Hypertension or IPAH? (idiopathic)
unclear etiology
mean PAP > 25 at rest, > 30 w/ exercise
absence of a demonstrable cause
what are 6 causes of Secondary Pulmonary HTN?
1) parenchymal lung dz
2) chronic thromboembolic dz
3) left sided valvular disease
4) myocardial disease
5) congenital heart disease
6) systemic connective tissue disease
what are the 5 groups of PAH? which ones do we need to know?
1) PAH (IPAH, heritable, BMPR2, PortoPH, CTDz, Schisto)
2) PAH due to Heart disease
3) PAH due to Lung Disease
4) CTEPH (Chronic thromboembolic PH)
5) PAH due to multifactorial etiology
need to know 1 and 4
why are the disease process of Group 1 grouped together? what is their common feature?
plexiform lesions
in general, what is the pathogenesis of PAH? what are two associated factors?
PAH is an imablance of vascular effectors (constrictors and dilators) in favor of the vasoconstrictors
Associated environmental factors
associated genetic abnormalities
which of the collagen vascular diseases is most often associated with PAH?
systemic sclerosis
clicker ?
In addition to systemic sclerosis, what are 2 other associated conditions for PAH? include percent
1) HIV - 0.5%
2) Sickle Cell - 10% (hemogloinopathy in general)
Familial PPH - gene mutation leading to defective function of what protein?
(THIS IS MUST KNOW)
BMPR2
bone morphogenic protein receptor type II
history of which class of medications is important to obtain in a pt w/ suspected PAH?
stimulants such as Fenfluramine/Phentermine
(appetite suppressors)
have to get this hx if you suspect PAH
(especially obese pts)
PPH pathogenesis w/ regards to nitric oxide - what do you see in the pts w/ PAH in their endothelium?
endothelium showed negligible immunohistochemical staining for nitric oxide synthase
they do not have enough NO locally
pathogenesis of PAH - what is endothelin 1 and what does it do in PAH
ET-1 is a potent vasoconstrictor and mitogen for SM cells
in PAH, it localizes to muscular pulmonary arteries - causes constriction
what factor do you see overexpressed in plexiform lesions in PAH?
VEGF
PPH pathogenesis and serotonin
where is serotonin stored?
what does it do to pulmonary vasculature?
what is its role in pathogenesis of PAH?
stored mainly in platelets
associated with pulmonary vasoconstriction and proliferation of SM cells
plasma serotonin concentrations are higher than normal in PPH
what is the pathogenesis of anorexiants in PPH? (This is impt to know)
appetite suppressant drugs may generate PAH by blocking volt-gated potassium channels
these volt gate K channels control the cell-membrane potential and release of calcium
blocking them leads to an increase in intracellular calcium, more contractility, and thus constriction
what are 5 presenting symptoms of PPH?
Fatigue Exertional Dyspnea Exertional chest pain Exertional syncope edema
what are 5 findings on physical exam of PPH
1) dyspnea - variable severity
2) apical impulse shifted outwards (R heart, it shifts towards mid axillary line)
3) parasternal heave (b/c of RV enlargement)
4) palpable P2, and accentuated
5) widely split S2
if you suspect PAH, what is the most appropriate diagnostic test to perform next (first after HnP and shit) *** know for boards (and exam)
Echo
good screening test
what would be signs seen on echo that would indicated PPH?
dilated RV, RVSP increased drastically (normal around 15-20)
if you see indicative signs of PPH on echo, what is the next step?
Right heart catheterization
this will confirm presence of PAH
in a R heart cath report, the parameter that distinguishes PAH (arterial HTN) from PVH (venous HTN) is…
(This is must know concept)
the PCWP - pulmonary capillary wedge pressure
this is a surrogate measure for L Atrial pressure
(Swan Ganz catheter)
if the PCWP is less than 15, pt does not have L heart failure
just b/c it was a clicker question - define vasoreactivity and compare prognosis of pts w/ PAH who are and are not vasoreactive
vasoreactivity - if we give vasodilators, will the vasculature respond to them?
pts who are vasoreative have better prognosis
what agent do we use in the cath lab to see if pts are vasoreactive or not?
nitric oxide inhaled
after admin of nitric oxide what parameters for MPAP do we expect to see if a pt is vasoreactive
> 10 mm Hg drop in MPAP
and MPAP should drop to less than 40 mm Hg
what measurement is used to measure the pulmonary artery pressure (he told us to remember this)
tricuspid regurgitant jet velocity
what are the 2 conditions that can cause exercise desaturation even at mild stage?
PAH
Pulmonary Fibrosis
what are the PFT findings in PAH?
USMLE
isolated reduction in DLCO
no change in FEV1, FVC, and TLC
which agent should be selected for a pt w/ PAH who is short of breath at rest? (USMLE)
Epoprostenol
a prostacyclin analog
(“prost”)
what is the anticoagulant of choice in treating PAH? and why?
warfarin
use of anticoagulants has been shown to improve survival of PPH pts
when comparing the functional classes (I - IV) who has better prognosis?
Functional classes I and II tend to live for longer than those who fall into classes III and IV
CPR after CV collapse in PAH is usually successful or unsuccessful? (good to know)
usually unsuccessful
name the ET-1 receptor antagonists
Bosentan, Ambrisentan, Macitentan
