REVIEW ARTICLE
PULMONARY HYPERTENSION:
A COMPREHENSIVE REVIEW
Tasleem Raza1, MD; Muhammad Dilawar 2, MD
Introduction
ulmonary circulation has an extensive
surface area of about 50-70 m 2 at rest1. It
is normally a high flow, low pressure, and
low resistance system which can accommodate
marked increase in cardiac output without any
significant increase in pressure. However, with
abnormal pulmonary vasculature, pressure rise
can approach up to systemic levels1,2 . Pulmonary
arterial hypertension (PAH) was first described in
1891 in a case report. The term “primary
pulmonary hypertension” was first used in 1951
to describe the clinical features and Hemodynamics
of 39 patients3. Prior to specific therapies for
pulmonary hypertension (PH), idiopathic
pulmonary arterial hypertension (IPAH) was
universally fatal with a median survival of 2.8
years4. Until recently, medical therapies were
mostly ineffective in improving symptoms or
survival. Over the last decade, various therapies
have become available; however they are very
expensive and not yet feasible in resource poor
countries. We briefly summarize a classical case
of pulmonary hypertension followed by a review
on this topic.
P
Fig.1: CXR (PA view): Markedly dilated main pulmonary
artery with Cardiomegaly.
Case summary: A 31-year-old, non-smoker,
Filipino male security guard presented to our
institution in September 2005 with intermittent
retrosternal chest pain of few months duration.
Chest pain was precipitated by activity and
associated with sweating and dizziness. There
was also history of intermittent palpitations but
no cough, sputum, hemoptysis or leg swelling.
Past medical history was unremarkable for drug
use, high risk HIV behavior or liver disease and
there was no history of pulmonary hypertension
in his family.
On physical examination, pulse was 90/min,
BP 125/75 mmHg, RR 16/min and O2 saturation
of 96% on room air. Other significant findings
were normal JVP, loud S2 and a systolic murmur
at left sternal border. There was no parasternal
heave, hepato-splenomegaly, edema or signs of
connective tissue or chronic liver disease and
lung fields were clear on auscultation. On initial
work-up: complete blood counts, electrolytes,
renal function and liver function tests were
unremarkable and arterial blood gas on room air
during resting phase was: pH 7.42, PCO2 38,
PO 2 82 and O2 saturation 96%. Chest X-ray
(Fig.1) showed cardiomegaly, enlarged
Pulmonary arteries and oligemic lung fields.
Electrocardiogram (Fig.2) revealed normal sinus
rhythm, right axis deviation, right atrial
enlargement and right ventricular hypertrophy.
Transthoracic Echocardiogram (Fig.3 a, b)
showed dilated right atrium and right ventricle,
intact interatrial septum, moderate tricuspid
regurgitation, pulmonary artery estimated
systolic pressure of 110 mmHg and left
ventricular ejection fraction of 58%. He was
diagnosed as a case of severe pulmonary
hypertension, most likely idiopathic pulmonary
arterial hypertension. Subsequent work-up
included pulmonary function tests which showed
FVC 2.34 (55% of predicted), FEV1 1.63 (54%
of predicted), FEV1/FVC 70, no bronchodilator
reversibility, total lung capacity 92% of
predicted, residual volume 188% and diffusion
95% of the predicted. A ventilation perfusion
scan revealed heterogeneous distribution and
Correspondence to: 1Tasleem Raza, MD, Consultant Pulmonologist & Critical care, Dept. of Medicine, Hamad Medical
Corporation, PO Box 3050, Doha, Qatar. E-mail: tmohd1@hmc.org.qa
Muhammad Dilawar, MD, Consultant Pediatric Cardiologist, Cardiology and Cardiovascular Surgery Dept., Hamad Medical
Corporation, PO Box 3050, Doha, Qatar.
2
90
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Pulmonary Hypertension: A Comprehensive Review
Fig.2: ECG showing right atrial dilatation and right ventricular hypertrophy.
no segmental defects, interpreted as very low
probability for pulmonary embolism. Holter
monitoring revealed frequent ventricular ectopy
and short runs of supraventricular tachycardia.
Spiral chest CT (Fig.4 a, b) scan demonstrated
dilated main, right and left pulmonary arteries,
no pulmonary embolism, dilated right atrium and
no parenchymal lung disease. On screening
polysomnography, respiratory disturbance index
was 6 and average O2 saturation 93%. Liver
function tests, HIV, schistosomal serology and
thyroid function tests were all normal or
negative. Abdominal ultrasound and Doppler did
not show any evidence of cirrhosis or portal
hypertension. Low dose atenolol was started for
ectopy, however after a syncopal episode
atenolol was discontinued and he was admitted
for cardiac catheterization. Cardiac cath
Fig.3b: Doppler echocardiogram showing tricuspid
regurgitation with peak gradient of 101 mmHg (suprasystemic
RV pressure).
Fig.3a: Transthoracic echocardiogram: Apical 4 chamber
view showing markedly dilated right atrium and right
ventricle.
Fig.3c:Apical 4 chamber view after stent placement showing
interatrial stent in good position with moderate RA and RV
dilation.
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Pulmonary Hypertension: A Comprehensive Review
Fig.4 a: Chest CT: Dilated main, right and left pulmonary
arteries with no filling defect to suggest chronic
thromboembolism.
hemodynamics on room air showed mixed
venous satutation of 58%, systemic satutation of
95%, right ventricular pressure of 108/20 mmHg
(80% systemic), pulmonary artery pressure
111/66 with mean of 75 mmHg, pulmonary
artery wedge pressure with mean of 8 mmHg,
Qp and Qs of 1.64 L/min/m2 each without any
intracardiac shunting and pulmonary vascular
resistance of 40 Woods units/m2. Respective
values after 100% supplemental oxygen (nitric
oxide was not available in cath lab that day)
were mixed venous saturation 80%, systemic
sat of 100%, no change in pulmonary artery
pressure, Qp and Qs were increased to 3
L/min/m2 and hence the pulmonary vascular
resistance was reduced to 26 Woods units/m2.
After this hemodynamic cath, he was started
on Lasix, Digoxin, Warfarin and Sildenafil and
calcium channel blockers were not started
because of unresponsiveness of pulmonary
arterial pressure to oxygen inhalation. He
remained stable for 15 months but then
presented with worsening dyspnea associated
with mild hemoptysis and increasing leg edema.
Physical exam was significant for O2 saturation
of 88% on room air and 97% on 3L O2 inhalation,
conjunctival icterus, pitting edema up to the
knees and mild hepatomegaly. Blood chemistry
showed mild liver function derangement and
abdominal ultrasound was unremarkable.
Increase in lasix dose, supplemental O2 to keep
SpO2 > 92% and atrial septostomy/stenting was
recommended. In March 2007, he was taken to
cath lab and procedure was started under
general anesthesia. Quick hemodynamic
assessment with 100% oxygen inhalation
showed systemic O2 saturation of 96%, right
92
Fig.4 b: Markedly dilated right atrium.
atrial pressure 26/18 with mean of 21 mmHg and
right ventricular pressure of 88/16 mmHg; then
under transesophageal echocardiogram and
Fluoro/Cine guidance, 10 mm x 19 mm Genesis
Opta-Pro stent was placed in interatrial septum
(Fig.5 a, b, c). Respective values after stenting
were 85%, 19/17 with mean of 15 mmHg and
103/3 mmHg. Gradually marked improvement in
leg edema, resolution of hemoptysis,
normalization of liver function test and slight
improvement in exertional dyspnea was
observed. He is still on digoxin, lasix, warfarin
and sildenafil and during his last clininc visit
oxygen saturation on room air was in mid 80’s
and echocardiogram (Fig. 3 c) showed patent
stent with right to left atrial shunting and
improvement in right atrial and ventricular size.
I. Definition of pulmonary hypertension:
PH is defined as mean pulmonary artery
pressure (PAPm) of 25 mmHg at rest and 30
mmHg during exercise5,6 and pulmonary arterial
hypertension is diagnosed when PH is present
with normal pulmonary capillary or left atrial
pressure that is <15 mmHg5,6.
II. Nomenclature and classification:
PH was traditionally divided into primary and
secondary. This classification has been
replaced by the one proposal at Third World
Conference on PH in 2003. Currently PH is
divided in to five major categories with further
subdivisions in each category (Table 1). PAH
could be idiopathic, secondary to other medical
conditions or associated with significant
venous or capillary involvement. Idiopathic
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Pulmonary Hypertension: A Comprehensive Review
Fig.5a: Cine pictures during interatrial stent placement: Cine
showing predilated premounted stent in interial septum.
Fig.5b: Cine showing inflated balloon with premounted stent.
Fig.5 c: Arrow showing fully dilated stent in interatrial
septum.
PAH could be either sporadic or familial.
Pulmonary venous hypertension is due to left
heart disease with elevated pulmonary
capillary artery pressure. PH associated with
hypoxemia is due to lung disease and other
disorders associated with hypoxemia. PH due
to chronic thrombotic or embolic disease is due
to prior pulmonary embolism in majority of
cases. Miscellaneous category of PH includes
diverse disorders like sarcoidosis and fibrosing
mediastinitis.
III. Clinical features:
Patients with pulmonary hypertension can
present with varied cardiopulmonary symptoms.
Exertional dyspnea is the most frequent
symptom and unexplained dyspnea should
always raise the suspicion of PH. Chest pain and
syncope are usually late symptoms. Patient may
present with symptoms of right heart failure such
as peripheral edema or ascites. PH may be
asymptomatic in early stages and may be an
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Table 1: Nomenclature and classification of pulmonary hypertension*
Pulmonary arterial hypertension:
Sporadic
Familial
Related to:
Collagen vascular disease
Congenital systemic to pulmonary shunts
Portal hypertension
HIV infection
Drugs and toxins
Other (glycogen storage disease, Gaucher disease, hereditary
hemorrhagic telangiectasia, hemoglobinopathies, myeloproliferative
disorders, splenectomy)
Associated with significant venous or capillary involvement
Pulmonary veno-occlusive disease
Pulmonary capillary hemangiomatosis
Pulmonary venous hypertension:
Left sided atrial or ventricular heart disease
Left sided valvular heart disease
Pulmonary hypertension associated with hypoxemia:
Chronic obstructive pulmonary disease
Interstitial lung disease
Sleep-disordered breathing
Alveolar hypoventilation disorders
Long-term exposure to high altitude
Pulmonary hypertension due to chronic thrombotic or embolic disease:
Thromboembolic obstruction from proximal or distal pulmonary arteries
Pulmonary embolism (tumor, parasites, foreign material)
Miscellaneous:
Sarcoidosis, Histiocytosis X, Lymphangiomatosis, compression of pulmonary vessels
(adenopathy, tumor, fibrosing mediastinitis)
*Adapted from Annals of Internal Medicine 2005; 143(4): 282-292
incidental finding on echocardiogram performed
for other reasons. A family history of PH, use of
Fenfluramine appetite suppressants, cocaine or
amphetamines, prior history of
deep vein
thrombosis (DVT) or pulmonary embolism (PE),
chronic liver disease or portal hypertension, risk
factors for HIV, thyroid disease, splenectomy
and sickle cell disease should be sought in all
patients suspected to have PH.
IV. Work-up in suspected PH:
The goals of work-up in PH include confirmation
of diagnosis, establish the category based on
classification system, establish underlying cause,
quantify severity, hemodynamic effects and
functional impairment. Nothing can be substituted
for a detailed history which will help to narrow
94
down the etiology of PH. Clinical examination is
vital to make its diagnosis and can reveal
hyperdynamic precordium (RV heave), loud S2,
early diastolic (pulmonary regurgitant) murmur at
pulmonic area, long systolic (tricuspid
regurgitant) murmur at lower sternal border and
the hemodynamic effects of right heart failure in
the form of raised JVP, hepatomegaly, ascites
and peripheral edema. Examination will also help
to exclude any congenital/acquired left sided
obstructive/ regurgitant heart lesion. Vital signs
and room air oxygen saturation helps to
determine the severity of disease.
The usual approach is to start with noninvasive
and simpler tests followed by more complex
testing. Initial aim is to exclude pulmonary venous
hypertension followed by exclusion of conditions
associated with hypoxemia and chronic thormbo-
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Pulmonary Hypertension: A Comprehensive Review
embolism. This is followed by exclusion of causes
associated with connective tissue disease, HIV,
chronic liver disease and other rare disorders.
a. Electrocardiographic features of
hemodynamically significant PH include: right
axis deviation, right atrial enlargement and right
ventricular hypertrophy.
b. Chest X-ray (CXR) may show enlarged
main and branch pulmonary arteries with
attenuation of peripheral vascular markings.
CXR changes of obstructive or restrictive lung
disease or pulmonary congestion may be helpful
in elucidating the cause of PH.
c. Echocardiography is helpful in confirming
the diagnosis as well as excluding the Left sided
cardiac lesions as the etiology of PH. A thorough
2-D, color and Doppler echocardiographic study
is needed to delineate cardiac anatomy and
function, great arterial vessels, systemic and
pulmonary veins, and to assess the severity of
PH and its hemodynamic effects. Systolic
pulmonary artery pressure (PAP) can be
estimated precisely by tricuspid regurgitation
and diastolic PAP by pulmonary regurgitation
Doppler study. If transthoracic echocardiography
is technically difficult which generally happens in
teenagers and adults, then transesophageal
echocardiogram is indicated.
d. Blood work-up should include erythrocyte
sedimentation rate (ESR), anti-nuclear antibody
(ANA) test, liver function tests (LFTs), thyroid
function tests (TFTs) and HIV testing.
Significantly elevated ESR and ANA should
prompt further work-up for connective tissue
disorders (CTDs) and vasculitidis. However, it
should be kept in mind that up to 40% patients
with IPAH may have serological abnormalities.
Patients with liver disease from endemic
schistosomal areas need its serological work-up.
e. Pulmonary function testing (PFT) is done
to evaluate for possible obstructive or restrictive
lung disease. Isolated reduction in diffusing
capacity may be due to PH or underlying
thrombo-embolic disease.
f.
Ventilation
perfusion
Scan
is
recommended an initial investigation to evaluate
for chronic thrombo-embolic disease (CTED).
g. Pulmonary angiography is the definitive
test for CTED diagnosis.
h. Computed tomography (CT) scan of
chest may show various abnormalities in CTED,
including irregular pulmonary arteries, organized
thrombus, webs, increased bronchial artery
collateral flow, lung scars from prior infarction and
mosaic perfusion pattern. CT scan may also
show airway or parenchymal changes suggestive
of underlying lung disease as the etiology of PH.
i. Overnight pulse oximetry is important to
exclude nocturnal hypoxemia which may be
potential underlying cause of PH or a factor
exacerbating PH in IPAH.
j. Full sleep study is helpful in patients with
symptoms or overnight hypoxemia suggesting
obstructive sleep apnea.
k. Cardiac catheterization is required in most
patients with PAH to confirm the diagnosis, assess
its severity, guide medical therapy and provide
prognostic information. Right atrial, right ventricular,
pulmonary artery and pulmonary capillary wedge
pressures are recorded. Cardiac output by Fick’s
principle or by thermodilution technique is obtained.
In some patients left heart catheterization is also
performed if there is suspicion of left heart disease.
All the hemodynamic data is obtained at baseline
as well as after giving a short acting pulmonary
vasodilator. Nitric oxide is commonly used as the
pulmonary vasodilator agent although other agents
like prostacycline and adenosine can also be used.
Interventions like atrial septostomy or atrial septal
stenting can be performed in the cath lab if
indicated. A positive vasodilator response is defined
as 6,7.
- a decrease of at least 10 mmHg mean
PAP and
- achieving mean PAP < 40 mmHg and
- an increase or no change in cardiac
output and
- no or clinically acceptable fall in blood
pressure.
Vasodilator
responsive
patients
are
candidates for calcium channel blocker (CCB)
therapy 7,8. Approximately half of the patients who
are vasodilator responsive on initial testing
require additional PAH therapy beside calcium
channel blockers within 1 year 7,9. Unfortunately,
only < 10% patients are felt to have long-term
true vasoreactivity (NYHA I or II patients with
near normal hemodynamics on monotherapy
with CCB for 1 year) and are candidates for long
term calcium channel blocker monotherapy.
V. Management:
Management of secondary PH primarily focuses
on the treatment of underlying disease. Most of
the further discussion on management is
focused on patients with IPAH. Management can
broadly be divided in to following categories;
1. General recommendations for lifestyle
changes.
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Pulmonary Hypertension: A Comprehensive Review
2. Specific recommendations for women of
childbearing age.
3. Immunization and drug use.
4. Medical therapy.
5. Interventional and surgical therapies.
1. General recommendations for lifestyle
changes: Any activity causing sudden increase
in afterload or decrease in preload could be
potentially hazardous in PH. Hypoxemia is a
potent pulmonary vasoconstrictor and all the
activities leading to hypoxemia need to be
avoided in such patients. These patients need
proper education and advice such as:
- Physical activity is encouraged but should
always be graduated and sudden heavy
exertion should be avoided.
- Avoid hot baths or showers to prevent
peripheral vasodilatation.
- Avoid high altitude exposure to prevent
hypoxemia.
- Need for supplemental oxygen during air
travel should be assessed prior to any
travel plans.
- Avoid excessive sodium intake to prevent
salt retention.
- Encourage and strongly advise to quit
smoking and recommend the use of nonnicotine replacement therapies as a help
to quit smoking if needed, as nicotine is a
vasoconstrictor
2. Specific recommendations for women of
childbearing age: Pregnancy is associated with
marked hemodynamic physiological changes
which could be deleterious in patients with PH10.
Although, successful pregnancy outcomes have
been reported in patients with PH11, early
termination of pregnancy is recommended by
most experts in view of potential high mortality of
up to 50% 7,12 . Contraceptive use is recommended
in sexually active women of child bearing age.
Estrogen containing oral contraceptive use is
discouraged in view of increased risk of
thromboembolism12,13. Endothelial receptor
antagonist, Bosentan may decrease the efficacy
of hormonal contraception12,14.
3. Immunization and drug use: Influenza and
pneumococcal
vaccination
is
strongly
recommended to prevent respiratory infections. All
medication use including over the counter and
herbal medications should be discussed with the
physician prior to their use. All vasoconstrictor
medications including pseudoephedrine containing
compounds should be avoided. Appetite and diet
96
pills should also be avoided due to their association
with PH
4. Medical therapy: Therapies for PH involve
use of traditional therapies as well as relatively
new pulmonary vasodilator therapies.
a. Traditional therapies for PH: Use of most
of these therapies is based on biological
plausibility and extrapolation of data from other
cardiopulmonary disorders 15. These therapies
include anticoagulation, diuretics, digoxin and
supplemental oxygen.
i. Anticoagulation use is based on the
improved survival data from two small
retrospective studies as well as evidence of
microscopic in situ thrombosis16. In the absence
of
contraindications,
anticoagulation
is
recommended to keep target INR of 1.5 - 2.5. In
view of higher risk of bleeding in scleroderma
and hemoptysis in congenital heart disease,
anticoagulation use is controversial in these
disorders 12,17.
ii. Diuretic use is recommended for right
ventricular failure; however excessive diuresis
should be avoided to prevent hypotension.
Whether diuretics alter mortality or morbidity in PAH
is not known15,18 . Loop diuretics are traditionally
used and doses as high as 600 mg/day of
furosemide or 10 mg per day of bumetanide in
addition to metolazone of up to 20 mg/day may be
required. Spironolactone is also used in view of its
benefit in patients with left ventricular systolic
dysfunction related heart failure. Spironolactone
should not be used in patients with serum
creatinine > 2.5 mg/dl or potassium > 5.0 meq/L.
iii. Digoxin is used for right ventricular failure
and in patients with atrial flutter or fibrillation,
although it has not been studied extensively in
PH patients 15,19. If used as an inotropic agent,
trough levels should be kept between 0.5 and 1.0
ng/ml to prevent its adverse effects. Digoxin
should not be used in patients with recent acute
coronary syndrome because of increased risk of
death from arrhythmias or myocardial
infarction20,21 .
iv. Oxygen supplementation is recommended
in patients who are hypoxemic15,22 . Patients whose
PaO2 is consistently < 55; or SaO2 is < 89% at rest,
during sleep or with ambulation, should be
provided supplemental Oxygen therapy to keep
SpO2 > 90% at all times. Patients may require
supplementation at night and during air travel even
when day time sea level oxygenation is normal.
b. Pulmonary vasodilator therapies: Over
the last few years, many new pulmonary
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Pulmonary Hypertension: A Comprehensive Review
Table 2: Pulmonary vasodilator drugs, dosage and route of administration
Drug class
Calcium channel
blockers
Prostanoids
Endothelin-1
receptor
antagonists
Phosphodiesterase
inhibitors
Drug
Dose range
Route
Nifedipine
30 – 240 mg/day
Oral
Diltiazem
Epoprostenol
Treprostinil
Iloprost
Oral
IV
SQ
Inhaled
Beraprost
120 – 900 mg/day
2 – 40 ng/kg/min
0.625 – 1.25 ng/kg/min
2.5 – 5 mcg
6 - 9 inhalations/day
20 – 60 mcg TID
Bosentan
62.5 – 125 mg BID
Oral
Sitaxsentan
Ambrisentan
Sildenafil
100 mg/day
5 – 10 mg/day
20 mg TID
Oral
Oral
Oral
vasodilator medicines are available in addition to
the older ones. Medications used as pulmonary
vasodilators include calcium channel blockers
(CCB), Prostanoids, Endothelin receptor
antagonists and blockers, and phosphodiesterase
inhibitors (Table 2).
i. Calcium channel blockers: High dose
calcium channel blockers have shown improved
survival with long term use in patients with
positive vasodilator response 7,23 and are
relatively inexpensive oral medications.
Unfortunately, only a small number of patients
are candidates for these medications as CCB
are ineffective in vasodilator non-responsive
group and can potentially be dangerous by
inducing marked systemic hypotension and
potential death in these patients.
ii. Prostanoids: Prostacycline is produced in
vascular endothelium by arachidonic acid
metabolism and is a potent vasodilator and has
antiplatelet aggregation effect too.
Epoprostenol was the first medication to show
improved survival in severe PH and is the
treatment of choice for most severely ill
patients 6,7,24. Unfortunately, it has extremely short
half life requiring continuous intravenous infusion
with potential for central venous line related
sepsis as well as risk of dangerous rise in
pulmonary pressure even during brief interruption
in infusion. United States (US) food and drug
administration (FDA) has approved it for patients
in New York heart association (NYHA) class III
and IV with IPAH or PH due to scleroderma7,25. Its
use is mostly limited to patients with advanced
disease refractory to oral therapies.
Beraprost is an oral prostacycline analogue,
approved for PAH in Japan. In a 12 week trial in
Oral
PAH with functional class II and III, Beraprost
improved 6 minute walk distance but showed no
survival advantage 7,26.
Treprostinil is a prostacycline analogue with a
half life of 3 hours, which is a major advantage
over epoprostenol. It can be given subcutaneously
or intravenously. In United States, FDA has
approved it for PAH in NYHA functional class II, III,
and IV7,27 . Pain at infusion site may be a limiting
factor during subcutaneous use.
Iloprost is another Prostacycline analogue
with half life of 20 – 25 minutes. It can be
administered intravenously as well as by
inhalation route. Unfortunately, 6 to 9 inhalations
per day are required due to its short half life. It
has US FDA approval for PAH in NYHA
functional class III and IV7,28.
iii.
Endothelin-receptor
antagonists:
Endothelin-1 is a potent vasoconstrictor and two
endothelin receptor isoforms (A & B) have been
identified. Endothelin-A (ETA) receptor activation
leads to vasoconstriction and vascular smooth
muscle cell proliferation while endothelin-B
(ETB) receptors are involved in clearance of
endothelin from vascular beds.
Bosentan is a dual ETA/ETB receptor
antagonist which is approved in US for PAH in
NYHA class III and IV. Hepatotoxicity is the major
side effect of Bosentan and monthly monitoring
of liver function tests is recommended.
Sitaxsetan and Ambrisentan are newer
selective ETA receptor antagonists and
hepatotoxicity remains the major side effect of
these medications as well.
iv. Phosphodiesterase 5 inhibitors: Cyclic
guanosine monophosphate (cGMP) augmentation
by nitric oxide leads to pulmonary vasodilatation.
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Pulmonary Hypertension: A Comprehensive Review
cGMP is rapidly degraded by phosphodiesterase.
Sildenafil is a highly specific phosphodiesterse5 inhibitor which is approved for erectile
dysfunction and recently approved for PAH by US
FDA.
5. Interventional and surgical therapies:
Despite advancement in medical therapies for
PAH, prognosis remains poor and patients may
continue to deteriorate or stabilize only for few
years followed by deterioration again. Beside
these problems, drug cost is a major impediment
for use of newer pulmonary vasodilator therapies.
i. Atrial septostomy/stenting or septectomy:
This involves the creation of right to left interatrial
shunt in the cath lab (atrial septostomy/stenting) or
surgically (atrial septectomy) to decompress the
failing right heart. This is largely seen as a bridge to
lung transplant where advanced health care
resources are available. However in resource poor
countries, this may prove to be the best treatment
option. Worsening hypoxemia is an expected
outcome after these interventions, therefore patient
selection and size of right to left shunt becomes an
important consideration in such decisions. Timing
of such interventions remains crucial due to
significant morbidity and mortality of procedure if
performed in patients who are severely ill on
inotropic support in intensive care units29.
ii. Lung transplantation: In developed
countries, lung transplant remains an option for
the patients who deteriorate despite best medical
therapy. Availability of organs remains a major
hurdle and waiting lists are long. One year post
lung transplant survival in PAH is 66 to 75%30.
VI. Monitoring in PH
VIII. Conclusion
PAH is a debilitating disease with significant
mortality and morbidity. A structured approach for
the diagnosis is needed and team approach is
recommended to expedite the work-up, confirm
the diagnosis and start appropriate therapy.
Many newer medical therapies are available
for the treatment of PAH. However, most of the
new medications are expensive which is a major
limiting factor for their use in underdeveloped
countries. Lung transplant is also not an option in
resource poor countries. Creation of atrial right to
left shunting may be an appropriate therapy in
select group of patients and timing of procedure
is the key to achieve good results and reduce
procedure related morbidity. ? Heart Views
2007;8(3)90–99. © Gulf Heart Asosociation 2007.
REFERENCES:
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VII. Areas of confusion & uncertainties:
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It should be realized that most of the preceding
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98
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