Pulmonary arterial hypertension (PAH) is high blood pressure in the pulmonary arteries of the lungs. It can be caused by various conditions and is diagnosed through tests like echocardiograms, pulmonary function tests, and right heart catheterization. As PAH progresses, the increased pressure in the lungs puts strain on the right side of the heart. Treatment aims to relieve symptoms and slow disease progression through oral medications, inhaled treatments, IV therapies, and possibly lung transplantation in severe cases.

1. Pulmonary Arterial Hypertension
“The Other High Blood Pressure”
Michael J. Cuttica MD
Assistant Professor of Medicine
Northwestern Pulmonary Hypertension Program
Northwestern University
October 11, 2014

2. What is Pulmonary Hypertension?
• PH is high blood pressure in the blood vessels
in the lungs.
• The blood pressure in your lung is normally
very low:
– about 1/5 your systemic blood pressure
• Many disease processes can cause the
pulmonary blood pressure to rise.

3. What is the Anatomy?
Systemic BP:
Systolic 120 mmHg
Diastolic 80 mmHg
Mean 65 mmHG
Pulmonary Artery Pressure:
Systolic 20-30 mmHg
Diastolic 5-15 mmHg
PA (mean) <25 mmHG

4. Updated Clinical Classification of Pulmonary
Hypertension
(Dana Point 2008)
Class 1:
Pulmonary Arterial Hypertension
Class 1. Pulmonary Arterial Hypertension
1.1 Idiopathic (IPAH)
1.2 Heritable: BMPR2, ALK1/endoglin, Unknown
1.3 Drug and toxin induced:
Class 2. Pulmonary 1.4 Associated Hypertension with:
with Left Heart
1.4.1: Connective Tissue Disease
Disease
1.4.2: HIV infection
Class 3. Pulmonary 1.4.3: Portal Hypertension HTN
associated with lung
1.4.4: Congenital heart disease
disease and/or hypoxemia
1.4.5: Schistosomiasis
Class 4. Pulmonary 1.4.6: Chronic Hypertension hemolytic anemia
due to chronic
1.5 Persistent PH of the newborn
thrombotic and/or embolic disease
1’ PVOD and or PCH
Class 5. Pulmonary Hypertension with unclear or
multifactorial mechanisms (sarcoid, MPD, CRF on HD)

5. Where is the disease?
Class 4: CTEPH Class 3: PH
Class 1: PAH
Class 2: PVH
Class 5: PH – Multifact.

6. Clinical Classification of Pulmonary
Hypertension (Dana Point, 2008)
Class 1: PAH
mPAP at rest > 25mmHg
mPAP with exercise > 30mmHg
PCWP < 15mmHg
PVR >3 Wood units
Class 2: PVH
mPAP at rest > 25mmHg
PCWP > 15mmHg
Pulmonary Vascular Resistance (PVR):
Change in pressure/ flow
Right heart Pressure – Left heart Pressure
Cardiac Output
Class 3: PH associated with lung disease
mPAP at rest > 20mmHg
Underlying chronic lung disease:
COPD, ILD, Alveolar Hypoventilation Syndromes, Sleep
disordered breathing

7. What Causes PAH?
• Four Factors are thought to cause the
increased pulmonary vascular resistance that
characterizes the disease:
1.Vasoconstriction
• Under expression of vasodilators like NO and prostacyclin
• Over expression of vasoconstrictors endothelin-1
2.Remodeling of pulmonary vessel wall
3.Thrombosis in situ
4. Inflammation

8. What is “remodeling” of a pulmonary
vessel?
PAH Normal
Medial hypertrophy
• Abnormal Smooth
Muscle Cell growth
• Extension of smooth
muscle into small PA’s
• Abnormal Endothelial
cell growth
– monoclonal origin
• Inflammatory Cell
infiltration around
plexiform lesions.
• In situ thrombosis–
clots.

9. What is the Clinical Presentation of
PAH?
Breathlessness
Without overt signs of heart and lung disease
Fatigue
Weakness
Angina/Chest Pain
Edema/Swelling
Syncope/passing out
Clinical
Suspicion of
PAH

10. Why do Patients with PAH get short of
breath?
Your lungs are the source of oxygen that your body needs for physical activity
Oxygen from your lungs enters your blood as it flows through microscopic blood
vessels called capillaries that surround tiny air sacs called alveoli.

11. Reduced Blood Flow Means Less
Oxygen
If you have PAH, it is harder for blood to reach your lungs and pick up oxygen because
the pulmonary arteries become so narrow, the resistance increases, and blood can not
flow quickly through them.
Over time, this increased resistance to blood flow puts a strain on the right side of the
heart as it has to work extra hard to push blood through the lungs.

12. Right Heart Strain
As the right heart is strained over time we see it dilate/enlarge and we see the
function/squeeze of the right heart decrease.
With less oxygen in the blood stream and the right heart pumping less forcefully
patients feel tired more often and get short of breath quickly, especially when
exerting themselves.

13. How Do We Diagnose PAH?
• Typically, you undergo a series of tests to
determine if you have PAH or another illness with
symptoms similar to PAH.
• Making this determination is very important as
treatments for different conditions are very
different.
• Primary tests usually done first are:
– echocardiogram and pulmonary function testing.

14. What is an Echocardiogram?
• Uses sound waves to create a
picture of your heart and
measure blood flow
• Provides useful information
about the structure and
function of your heart
• Can provide an estimation of
the pressures in your
pulmonary artery.
Dilated Right ventricle with
reduced function

15. What is Pulmonary Function Testing?
• Determine the flow of air in
and out of the lung
– ? Obstructive lung disease
• Determine the volume of air
in the lung
– ? Restrictive lung disease
• How well does oxygen go
from your lungs and into
your blood?
– ? Vascular health of the lung

16. What is a Right Heart
Catheterization (RHC)?
• RHC is the gold standard test for making the
diagnosis of PAH.
– It is absolutely necessary before initiation of any
PAH specific therapy
• This test allows us to measure the blood
pressure in your lungs directly.
• It allows us to calculate how much blood your
heart is pumping in every minute.

17. What is a RHC?
• A thin catheter is inserted
through a large IV either in the
neck or groin.
• This catheter is then guided
through the right heart and into
the pulmonary artery
• Typically, a RHC can be performed
in less than 1 hour.
• Occasionally, an additional
catheter will be inserted into an
artery to measure pressures on
the left side of the heart.

18. What is the Anatomy?
Right Atrium:
2-8 mmHg
Left Atrium:
6-10mmHg
Left Ventricle:
Systolic 120 mmHG
Diastolic 6-12mmHg
PCWP:
6-12mmHg (must
be <PA diastolic)
Pulmonary Artery Pressure:
Systolic 20-30 mmHg
Diastolic 5-15 mmHg
PA (mean) <25 mmHG

19. How do we treat PAH?
• The goal of treatment for PAH is to relieve symptoms
and slow the progression of disease.
• Initial treatment decisions are based on how far the
disease has progressed and how symptomatic a
patient is.
• Treatment options include:
– Oral therapies: pills
– Inhaled therapies
– Continuous IV or subcutaneous infusion
– Surgery: lung transplant

20. Humbert M et al. N Engl J Med 2004;351:1425-1436

21. Conclusions
• Pulmonary hypertension is high blood
pressure in the blood vessels in the lungs
• Patients with scleroderma are at an increased
risk for developing this complication
• The diagnosis of this disease is made by
excluding other causes of symptoms and by
right heart catheterization
• Great advances in treatment have been made
in the last 10-15 years