Pulmonary Arterial HTN Flashcards
Normal hear anatomy
- superior vena cava
- inferior vena cava
- right atrium
- Tricuspid valve
- Right ventricle
- Pulmonary valve
- Pulmonary arteries
oxygen rich
- Pulmonary veins
- Left atrium
- Mitral valve
- Left ventricle
- Aortic valve
- Aorta
Pulmonary Arterial HTN (PAH) patho
-pulmonary arterioles narrow
-RV dilates
-pulmonary edema and damage
-thrombo and/or plexiform lesion formation
Pulmonary HTN (PH)
-higher than normal BP in arteries going from heart to lung
-mean artery pressure (MPAP) > 20mmHg at rest
-more common than PAH
Pulmonary Arterial HTN (PAH)
-progressive
-endothelial dysfunction
-elevated pulmonary arterial pressure and pulmonary vascular resistance
-rare
PH classifications
- PAH
- Left Heart Disease
- Lung Disease
- Chronic Thromboembolic PH
- PH from unclear mechanisms
Group 1: PAH causes
-unknown causes
-genetic/drug/toxin
-CHD, HIV, connective tissue disorders
Group 1: PAH tx
-meds fro PAH
-CCB in responders
-lung transplant
PAH (Grp1) Epidemiology
-rare
-2-7mil a year
-mean age 50 +/- 14
-underrecognized (1.1 years to heart catheter)
-1/5 asx > 2 years to diagnosis
PAH prognosis
-poor but improving
-15% mortality in 1 year
-median survival 6 years
-negative predictors: advanced functional class, poor exercise capacity, hight right atrial pressure, right ventricular dysfinction, low CO
Early PAH sx
-nonspecific = large differential diagnosis
-dizziness
-SOB
-palpitations
-fatigue
-edema
Late sx of PAH
-signs of right-sided HF
-syncope
-jugular venous distension
-SOB
-chest pain
-hepatomegaly
-swollen abdomen
-low BP
Diagnosis
-echocardiogram: eval RV function, PAP, and PVR
-Right Heart Catheterization: confirms dx, estimates severity, assess response to pulmonary vasodilators before starting therapy (AVT)
-exercise testing: distance walked in 6 min
-biomarkers: BNP and NTproBNP
Diagnositic imaging/procedure
-slide12
PAH labs
-mPAP > 20mmHg (mean pulmonary artery pressure)
-PAWP =/< 15mmHg (pulmonary artery wedge pressure)
-PVR > 2 wood units (pulm vasc resistance)
Pulmonary arterial wedge pressure (PAWP)
-estimates left atrial pressure
-normal 4-12
-PAH: 15mmHg
-elevated numbers = LV failure or mitral stenosis
Pulmonary vascular resistance (PVR)
-calc using mPAP and PAWP
-PAH: >2 wood units
WHO functional classifications
I: no limits
II: slight limit
III: marked limit
IV: inability to be active wo sx
Risk
Pharma options for PAH
-CCB (if vasoreactive +)
-PDE-5 inhibitors
-sGC
-ERAs
-Prostacyclins
-Direct pulmonary vasodilator (inpatient only)
Vasoreactivity test
-done in cath lab during initial hemodynamic eval
-acute response to pulmonary-specific vasodilators predicts response to CCBs
-use inhaled NO or epoprostenol
Positive Vasoreactivity test
=drop in mPAP>10 w PAP less than 40 w stable-improved CO
-can initiate CCB
CCB for PAH
-inc in calcium causes vasoconstriction and stimulates proliferation, migration, vascular remodeling
-only 5% of pt respond
-continually assess w vasoreactive test
-goal: improve to FCI or II
which CCBs to use
-nifedipine 120-240mg
-diltiazem 240-720mg
-amlodipine 20mg
-NO verapamil bc negative inotropic events