2. Pulmonary vascular diseases
Pulmonary vascular diseases are a
heterogeneous group of disorders with
multiple causes. Pulmonary vascular
disorders are caused by conditions that
directly affect the pulmonary vessels, as in
idiopathic pulmonary arterial hypertension
(IPAH), or by disorders outside of the lung, as
in pulmonary hypertension associated with
lung disease and hypoxemia.
3. Review of Respiratory CirculationReview of Respiratory Circulation
The pulmonary circulation consists of arteries, capillariesThe pulmonary circulation consists of arteries, capillaries
and veins.and veins.
The major role of the pulmonary circulation is to bring bloodThe major role of the pulmonary circulation is to bring blood
in to close proximity to air, so that gas exchange can occur.in to close proximity to air, so that gas exchange can occur.
The pulmonary vascular bed receives the entire cardiac output.The pulmonary vascular bed receives the entire cardiac output.
-high volume/low pressure system.-high volume/low pressure system.
Pulmonary Circulation:Pulmonary Circulation:
Bronchial Circulation:Bronchial Circulation:
• The bronchial arteries typically originate off aorta and supplyThe bronchial arteries typically originate off aorta and supply
airways (2% of cardiac output).airways (2% of cardiac output).
-low volume/high pressure.-low volume/high pressure.
• 1/3 of blood flow through the bronchial circulation empties into1/3 of blood flow through the bronchial circulation empties into
azygous vein.azygous vein.
• 2/3 of blood flow empties into pulmonary capillaries (broncho-2/3 of blood flow empties into pulmonary capillaries (broncho-
–pulmonary anastamoses).pulmonary anastamoses).
4. Pulmonary Hypertension
Which is defined as mean pulmonary artery
pressure over 25 mm Hg at rest or over 30
mm Hg with exercise.
In Pulmonary Hypertension there is:
1. Enlarged proximal pulmonary arteries,
2. Right ventricular hypertrophy
3. Right atrial dilation
5. Chamber Pressures in PAH
55
>30>30
Mean >24 at rest, >30 with exercise
PCWP <15 mmHg
6. Pathophysiology of PHTN
Hypoxemia causes vasoconstriction
Decreased perfusion worsens hypoxemia
Hypoxic alveoli cause arterioles to
vasocontrict further to preserve VQ matching
Pulmonary pressures increase and become
sustained
Right ventricle works harder, develops
hypertrophy and overload
16. Primary pulmonary hypertension
Defined as Pulmonary htn in the absence of
other disease of lungs or heart.
Develops: Young and middle aged women
Characterized by right heart failure, leading to
death in 2-8 yrs.
B/c of low cardiac output:
1. Weakness, fatigue, edema, ascites. Syncope
17. On Examination
Inspection:
1. Prominent JVP
2. Cyanosis
Palpation:
1. Left parasternal heave due to RVH
2. Systolic pulsation in 2nd
ICS due to dilated
pulmonary artery
18. Auscultation:
1. Loud pulmonary component of 2nd
heart sound
2. Systolic ejection click and flow murmur in
pulmonary area
3. Right ventricular S4
4. Advanced cases, tricuspid and pulmonary
regurgitation and signs of cor pulmonale are
found
19. Studies in Pulmonary HypertensionStudies in Pulmonary Hypertension
ECG: Right Ventricular Hypertrophy.
CXR: Dilated main pulmonary arteries/pruning of
peripheral vascular markings.
ABG: Hypoxemia with exertion.
PFT’s: Findings c/w underlying disease;
Decreased DLCO.
Echocardiogram:
Right heart catheterization:
Pulmonary Pressure MeasurementPulmonary Pressure Measurement
27. Risk Factors for Poor Prognosis
Age at presentation > 45 years
Functional class III or IV
Pericardial effusion
Large right atrial size
Elevated right atrial pressure
Septal shift during diastole
Increased BNP level
Failure to improve to a lower functional
class during treatment
28. Diagnostic Approach to Pulmonary HypertensionDiagnostic Approach to Pulmonary Hypertension
History and Physical Exam often suggestive.
ECG and echocardiogram: elevated pulmonary
pressures.
Right heart catheterization ± pulmonary angiography.
Identify treatable causes of secondary pulmonary
hypertension.
Hypoxemia (at rest or at night, with sleep apnea).
Chronic Thromboembolic Disease.
29. Routine Medical Treatments
Continuous oxygen
Pulmonary artery vasodilator
Anticoagulants
Treat and prevent thrombosis
Diuretics / Low Salt Diet
Decrease RA pressures
Treat right heart failure
Digoxin
Increases cardiac output
30. Routine Medical Treatments
Calcium channel blockers
Lowers pulmonary artery pressure
May improve right heart cardiac output
Exercise
Immunization
Prevent pulmonary infections
Opportunistic Infection Prophylaxis
Patients on immunosuppression (ILD)
31. Surgical Therapies
Pulmonary thromboendarterectomy
Correct mitral stenosis
Repair left to right shunt (ASD, VSD)
Atrial septosotomy to relieve RHF
when PA pressure exceeds systemic pressure
Lung transplantation
for advanced PHTN not responsive to medical therapy
~1,000 lung transplants/year in US
Heart / lung transplantation
32. Who Should Receive Advanced Medical
Therapy?
Group 1 (PAH) rarely respond to primary
therapies
Group 2 (cardiac abnormalities) usually
worsen with advanced therapies
Group 3 (COPD) respond to oxygen
therapy
Group 4 (thromboembolic) respond to
thrombectomy and anticoagulation
Group 5 unknown effects of advanced
therapies, primary therapy indicated
33. Treatment of Pulmonary HypertensionTreatment of Pulmonary Hypertension
Treat underlying disease.Treat underlying disease.
Oxygen supplementation- minimize hypoxicOxygen supplementation- minimize hypoxic
vasoconstriction.vasoconstriction.
Long term anticoagulation (even when not due to chronic PE).Long term anticoagulation (even when not due to chronic PE).
Vasodilators especially for primary pulmonary hypertension:Vasodilators especially for primary pulmonary hypertension:
Calcium channel blockers.Calcium channel blockers.
Prostacyclin.Prostacyclin.
Endothelin receptor blockers (Bosentan).Endothelin receptor blockers (Bosentan).
TransplantationTransplantation
34. Secondary pulmonary HTN
Hypoxia of any cause is the most important
stimulus of Pulmonary arterial vasoconstriction
leading to pulmonary HTN
Chronic lung disease
Chronic bronchitis/ Emphysema /Lung fibrosis
Increased pulmonary blood flow:
Left or right shunt: ASD, VSD, PDA
Increased pulmonary venous pressure:
Mitral stenosis/ Left ventricular failure/ Mitral
regurgitation/ Pulmonary thromboembolic disease
35. Treat the cause
Supplemental Oxygen for atleast 15hrs/ day
in patients with COPD
Inhaled NO
Anticoagulation: To dissolve small pulmonary
emboli
37. Clinical features
Dyspnea/ Cyanosis/ Clubbing/ Weakness
Features of Right heart failure:
1. Raised JVP
2. Right ventricular heave
3. Murmurs of pulmonary and tricuspid
regurgitation maybe present
38. Investigations:
CXR: Right ventricular enlargement and right
atrial dilation. Prominent pulmonary artery
ECG: Right ventricular hypertrophy
demonstrates right ventricular hypertrophy (right
axis deviation, possibly a dominant R wave in
lead V1, and inverted T waves in right
precordial leads) and a right atrial abnormality
(tall peaked P waves in lead II)
ECHOCARDIOGRAPHY:
Right ventricular dilation
39. Chest radiography
Signs of pulmonary hypertension:
Enlarged right descending pulmonary artery with diameter
≥15mm
The ratio of the diameter of right descending pulmonary
artery to trachea≥1.07
Bulge of pulmonary artery/with the height≥3mm
dilation of the main pulmonary artery and its branches
with concurrent underperfusion of the peripheral branches
Signs of right ventricular enlargement
Signs of underlying diseases and infection
In PAH, the pulmonary artery becomes stiff and narrow. The right ventricle has to work harder and harder to push blood through the narrow artery. When this happens, less and less blood is able to flow out into the body, and more and more symptoms of PAH begin to appear
Due to diseases that localize to small pulmonary arterioles
Slide 14 Summary---BM minhas if this helps!!
RVH, tall R in V1, tall S waves in V5-6, inverted T V1-3, peaked T in II
Uses sound waves to show the function of the right ventricle, to measure blood flow through the heart valves, and then calculate the systolic pulmonary artery pressure.