Pulmonary HTN Flashcards
WHO Classification
Group 1: PAH pulmonary artery HTN - mPAP>25mm Hg & PVR>3 W.U. and PCWP<15mm Hg -Idiopathic PAH -Heritable PAH (BMP, ALK1) -Drug and toxin induced -Associated --CTD --HIV --Portal HTN --Congential heart disease --Schistosomiasis --hemolytic anemia --persistent pulm HTN of newborn --pulmonary venoocclusive dz/pulm cap hemangio Group 2 (post capillary pulmonary HTN): Left heart dz - MS, systolic, diastoic dysfxn, HTN - mPAP>25, PCWP>15, TPG>12mm Hg Group 3: Lung disease or hypoxia -COPD -ILD -OSA -high altitude Group 4: Chronic thromboembolic Pulmonary HTN Group 5: Other --Sarcoid, Gauchers, MPd/o
PVR
PVR=(mPAP-PCWP) ie transpulmonary gradient/CO
>3.0 = post capillary pulmonary HTN
If transpulmonary gradient >12mm Hg - suggests component of left heart disease - rule out sleep apnea or throboembolic disease (sleep study or V/Q scan)
Precapillary pulmonary HTN
mPAP>25
PCWP<15
TPG>12
Post capillary pulmonary HTN
mPAP>25
PCWP>15
TPG<12
RHC with vasodilator challenge
Postive (iNO, adenosine, epoprosteronol)
dec in mPAP >10mm Hg to absolute mPAP<40mm Hg in setting of unchanged CO (or inc’d) - they can respond to CCB therapy
DO NOT TX Conn Tissue D/o PAH group 1 with CCB even if response to iNOS
Diastolic dysfunction
fluid challenge on RHC - check for inc in PCWP
Eisenmengers (VSD)
R->L shunt shunt not repairable if PA/Ao>2/3 more common in shunts distal to TV differential cyanosis = rev shunt at PDA risk of systemic embolism (clot or air) Pulm vasodilators improve Sx not mortality endocarditis ppx Bosentan and med management until heart/lung tx
Echo features of PAH
RAE, RVE/RVdysfxn, interventricular septal flattening, TR with elevated TR vel, reduced TAPSE,
Dx PAH
If no left sided reasons for PH - ie MS, AS, systolic or diastolic dyfxn - RVSP>40 warrants RHC in patients with unexplained dyspnea
Group 4
V/Q scan better than CTA
Group 3 - lung dz/hypoxia
dx with PFTs (obstructive or restrictive lung dz)
or overnight sleep study to r/o OSA (causes PH with hypoxic pulm vasoconstriction)
Group 2 - PH 2/2 left sided dz
MC type of Pulm HTN TPG normal (<12mm Hg) -> ie elevated PCWP owing to left heart disfunction and relatively low mPAP and PVR near normal (PVR<3 W.U.)
Can eventually develop “out of proportion” pulm HTN with left heart dysfxn group 2 - ie elevated TPG, elevated PVR - then test for concurrent precapillary pulm HTN
TTE to r/o A/mitral valve dz, systolic or diastolic dysfxn
LAE points to chronically elevated left heart filling
pressures
Treat underlying left heart disease with diuresis
PHTN Therapy
iNO responsive (fall in mPAP by at least 10 to less than 40mm Hg) without drop in CO in response to iNO, esoprosterol or adenosine -Tx with Dihydropyradine CCB (nifedipine or verapamil)
If neg vasodilator
1) Prostanoid (IV Esoprosterol) - needs cont IV pump
2) Endothelin antagonist (Bosentan) - hepatic dyfxn
3) PDE-5 Inhib (Sildenafil) - flushign/epistaxis
4) GMP Cycl inhib (riociguat) - hypotension
HIGH RISK patients need dual therapy
IV prostacyclin + endothelin rct ant (ambrisartan or bosentan)
PDE inhibitors
improve 6mWT and HD but not time to clinical worsening - need to combine with prostenoid or endothelin rct antag if severe sx
Riociguat (GMP)
contraindicated with PDE inhib and nitrates 2/2 hypotension
persistent PH after surgical pulmonary endarectomy or with inoperable CTEPH (not substitute for surgery)
Atrial septostomy
only with refractory RHF and severe PAH depsite max med therapy - for palliation and restoration of stability till tx
CTEPH (group 4)
Tx: Surgical pulm endarectomy
Surveillence - 6MWT
see reduced PAP, dec PVR, red RH sizes, red TR
TTE annually
High risk features Pulm HTN
NYHA IV Syncope RAP>15 6MWT<300 pVO2<12 C.I.<2 RVEF<35% TAPSE<1.5cm
High risk therapy
Should include epoprostenol
Monitor therapy of PHTN
6MWT >380m normal or near normal BNP normal or near normal RV Fxn WHO fxn class I or II CI >2.5 VO2 >15ml/min/kg
Eisenmenger’s Syndrome
near systolic pulmonary blood pressures Pulmonary HTN mPAP>25 and R->L shunt - typically shunts below TV (ie VSD, PDA) PDA eisenmengers have differential cyanosis unrepaired VSD blue lips on exertion avoid preg, exertion Bosentan - endothelin antagonist improves 6MWT, symptoms Do not improve survival
DO NOT USE Vasodilators
-will increase right to left shunt by decreasing SVR
de Novo class II pulm htn
tadalafil + ambrisentan
Pulm HTN and h/o cancer
r/o CTEPH with v/q scan
Group 1 Idiopathic PAH
anticoagulants (warfarin 1.5-2.5), oxygen, diuretics +- CCB if reactive to iNOS testing
Prostanoids - Eposprostenol, treprostinil (IV,SQ, inhaled), iloprost (inhaled)
Epoprostanol - improved 6MWT, QOL, survival
-with scleroderma improved 6MWT, HD
Trepostenil - only improved 6MWT, not survuval or clinical worsening
Iloprost - improvement in NYHA class, time to clinical worsening and 6 MWT
Endothelin rct antagonist (Bosentan, ambresartan)
Bosentan - improved 6MWT, time to clinical worsening
-needs LFTs
Ambresartan - improved 6MWT, time to clinical worsening
-no LFTs needed
PDE inhibitors (Sildenafil, tadalafil) inhibit hydrolyssi of cGMP
Sildenafil - improved 6mWT and HD NOT time to clinical worsening
Tildenafil - improved 6MWT only
Guanylate Cyclase Inhibitor - Riociguat
improved 6MWT, time to clinical worsening
peristent PH after group 4 CTEPH surgery or pt who ware not surgical canddiateas
contraindicated with nitrates
