·
Mean pulmonary artery pressure = 12 +/- 2 mmHg
·
Mean pulmonary capillary wedge pressure = 6 +/-
2 mmHg
·
Cardiac out put = 5L/min
·
Pulmonary vascular resistance = (mPAP – mPCWP) /
CO = 1.5
PULMONARY
HYPERTENSION
·
mPAP > 25 at rest or >30 during exercise
·
Associated with
o
pulmonary vascular disorders
§
acute pulmonary thromboembolism
§
1ry pulmonary hypertension
§
Multiple pulmonary artery stenosis
§
Pulmonary veno-occlusive disease
§
Chronic pulmonary thromboembolism
§
Parasitic infection (Schistosomiasis)
o
lung parenchyma diseases
§
COPD
§
Pulmonary fibrosis
o
Musculoskeletal disorders
§
Kyphoscoliosis
§
Poliomyelitis
§
Myasthenia gravis
o
Disturbance of respiratory control
§
Obstructive sloop apnoea
§
Morbid obesity (Pickwickian syndrome)
§
Cerebrovascular disease
o
Cardiac disorders
§
Mitral stenosis
§
Left ventricular failure
§
Left atrial myxoma
§
Congenital heart disease with Eisenmenger’s
reaction
o
Other
§
Appetite-suppressant drugs
§
Type 1 glycogen storage disease
§
Lipid storage disease
§
Rheumatic autoimmune disease (SLE)
§
Hepatic cirrhosis
§
Sickle cell disease
·
Causes
o
Precapillary
o
Capillary
o
Postcapillary
·
Outcome
o
Right ventricular dilatation
o
Right ventricular failure
o
Death
·
Management
o
Treatment of primary cause
§
Chest physiotherapy
§
Good nutrition
§
Early antibiotics in patients with cystic
fibrosis and bronchiactasis
§
Surgical and medical therapies to optimize
cardiac lung functions
§
Owygen
§
Anticoagulation
·
Adverse factors
o
Right ventricular dysfunction
o
Reduced 6 minutes walk distance
Primary pulmonary
hypertension
·
Increased PAP
·
Increased PVR
·
Normal PCWP
·
More in females (3;1) – 3rd decade
·
Men – 4th decade
·
6-12% familial origin (autosomal dominant)
·
Related to some drugs
o
Aminorex fumaratre
o
Amphetamine-like appetite suppressants
o
Talc inhaled with cocaine
o
Fenfluramine and Phenteramine in combination
(weight loss drug)
·
Other similar conditions
o
Plexogenic pulmonary arteriopathy
o
SLE
o
Hepatic cirrhosis
o
Eisenmenger’s reaction
·
Clinical presentation
o
Insidious onset
o
RVF
·
Investigations
o
CXR –
§
Enlarged pulmonary arteries and branches
§
Pruning of peripheral arteries
§
RA or RV enlargement
o
ECG
§
RVH
§
RA enlargement (P Pulmonale)
o
Echocardiography
§
RVH
o
Normal pulmonary function test
o
Diagnosis is by CT pulmonary angiography
·
Treatment
o
Warfarin, oxygen, Calcium channel blockers
o
Oral endothilin receptor antagonists
o
Prostanoid analogues
o
Sildenafil
Chronic cor Pulmonale
Enlargement
of the right ventricle due to increased afterload.
·
Clinical
features
o
Chest
pain
o
exertional
dyspnoea
o
syncope
o
fatigue
o
sudden
death
o
symptoms
due to pulmonary hypertension
·
signs
o
cardiovascular
system
§ prominent a wave
§ parasternal heaves
§ loud pulmonary component to the second heart
sound
§ right ventricular fourth heart sound
§ systolic pulmonary ejection click
§ mid systolic ejection murmur
§ early diastolic murmur (pulmonary
regurgitation – Graham steel murmur)
§ pansystolic murmur, large jugular ‘cv’ venous wave (tricuspid regurgitation)
·
investigations
o
CXR –
§ Right ventricular enlargement
§ Right atrial dilation
§ Prominent pulmonary artery
§ Peripheral pruning
§ Oligaemic peripheral lung fields
o
ECG
§ Right axis deviation dominant (R wave in the
V1 and inverted T waves in right recordial leads)
§ Right atrial abnormality ( tall P waves in
L11)
o
Echocardiography
§ RVH/dialation
·
Treatment
o
Diuretics
for right ventricular failure
o
Oxygen
therapy
Pulmonary Embolism
·
Most
emboli come from pelvic and abdominal veins
·
Some
come from femoral deep venous thrombosis, axillary thrombosis
·
Clots
form as a result of
o
Sluggish
blood flow
o
Local
injury
o
Compression
of vein
o
Hypercoagulable
state
o
Tumor
o
Fat
amniotic fluid
o
Foreign
material
·
Clinical
features
o
Sudden
onset of unexplained dyspnoea
o
Pleuritic
type chest pain, Haemoptesis - infarction
·
Small
medium pulmonary embolism
o
Haemoptesis
in 30%
o
Tachypnoea
o
Localized
plural rub
o
Coarse
crackles over the area
o
Exudative
plural effusion
o
+/-
fever
·
Massive
PE
o
Sudden
collapse
o
Severe
central chest pain
o
Shock
o
Pale
o
Sweaty
o
Tachycardia
o
Peripheral
shut down
o
Hypotension
o
Increased
JVP with prominent a wave
o
Right
ventricular heave
o
Gallop
rhythm
o
Widely
split second heart sound
·
Multiple
recurrent pulmonary emboli
o
Increased
SOB over weeks
o
Weakness
o
Syncope
o
Exertional
angina
o
Right
ventricular heave
o
Loud P2
·
Diagnosis
o
The
presentation is nonspecific, so PE is pulmonary embolism is suspected if no
other cause can be found.
·
Investigations
o
Small/medium
pulmonary emboli
§ CXR
·
Normal
·
Linear
atelactasis
·
Blunting
of costophrenic angle
·
Raised
hemidiaphragm
·
Wedged
shaped pulmonary infarct (rarely)
§ ECG
·
Normal
·
Sinus
tachycardia
·
Atrial
fibrillation
·
Tachyarrhythmia
·
Right
ventricular strain
§ FBC
·
Polymorphonuclear
leukocytosis
§ Elevated ESR
§ Increased lactate dehydrogenase
§ Plasma D dimer
·
Exclude
PE if undetectable
§ Radionuclide ventilation/perfusion scan
§ USS – find clots in pelvic or iliofemoral
veins
§ Contrast enhances CT angiograms
§ MR angiography
o
Massive
PE
§ CXR –
·
Pulmonary
oligaemia
·
Pulmonary
artery dilatation in the hila
§ ECG
·
Right
atrial dilation
·
Tall
peeked P waves
·
Right
ventricular strain
·
RV
dilation
·
Right
axis deviation
·
RBBB
·
T
inversion in right precordial leads
·
S1, Q3,
T3
§ Blood gases
·
Arterial
hypoxaemia
·
Low
arterial CO2
§ Echocardiography
·
Vigorously
contracting left ventricle
·
Dilated
right ventricle
·
Clot in
right ventricular outfoe tract
§ Pulmonary andiography
o
Multiple
recurrent PE
§ CXR –
·
Normal
·
Enlarges
pulmonary arterioles
·
Oligaemic
lung fields
§ ECG
·
PHT
§ Leg imaging
·
Thrombi
§ V/Q scan
·
Pulmonary
infarct
·
Multidetector
CT
o
Small
emboli
·
Treatment
o
Acute
management
§ High flow oxygen
§ Bed rest
§ Analgesics
o
Severe
§ IV fluids
§ Inotropic agents
o
Fibrinolytic
therapy
§ Streptokinase 100 000 units IV for 12-72
hours
§ Surgical embolectomy
·
Prevention
of further emboli
o
LMWH
o
unfractionated
heparinoral anticoagulants are begun immediately and continued for 6 weeks – 6
months, sometimes lifelong
o
IVC
filter
References:
Kumar P, Clark M, 2009, Clinical Medicine, 7th
edition, Saunders Elsevier, pp 781 -786
