1. 5/98MedSlides.com1 Pulmonary (Arterial) Hypertension www.medslides.com

2. 5/98MedSlides.com2 Definitions Pulmonary arterial hypertension –acute (pulmonary embolism, ARDS) –chronic (clinically more common) Pulmonary venous hypertension –pulmonary venous (LA pressure) > 12 mmHg –Hallmarks: pulmonary congestion and edema –Invariably, PVH elicits PAH Cor Pulmonale –pulm HTN with RV hypertrophy and dilatation

3. 5/98MedSlides.com3 Survival as a Function of Mean Pulmonary Arterial Pressure Mean PA Pressure Prog Resp Res 1975, 9:10 mm Hg

4. 5/98MedSlides.com4 Pulmonary Circulation Before birth –pulmonary and systemic pressure are equal in the order of 70/40 (mean 50) After birth –ductus arteriousus closes, lung expands, PA pressure falls to 1/2 of systemic level –PA pressure gradually decrease over weeks to reach adult level

5. 5/98MedSlides.com5 Pulmonary Circulation Pulmonary circulation is “protected” from being hypertensive –large capacity –great distensibility –low resistance –modest amounts of smooth muscle in the small arteries and arterioles

6. 5/98MedSlides.com6 Pulmonary Hemodynamics PA pressure (mmHg)20/12, 1538/14, 25 LA pressure (mmHg)5.05.0 Cardiac Output6 L/min6 L/min PVR(R Unit)1.73.3 PVR = -------------------- ; CGS units = R units x 80 PA - LA Cardiac Output SeaAltitude Level15,000 ft

7. 5/98MedSlides.com7 Pulmonary Arterial Hypertension pathophysiology Decrease in total cross-sectional area –lung resection Narrowing of the lumen of the small muscular arteries and arterioles resistance vessels (  P = Q x R) –chronic hypoxia with vasoconstriction

8. 5/98MedSlides.com8 Primary or Idiopathic Pulmonary Hypertension Plexogenic Thromboembolic (small emboli) Veno-occlusive disease Pulmonary capillary hemangiomatosis

9. 5/98MedSlides.com9 Secondary Pulmonary Hypertension Hypoxic –chronic lung disease, sleep apnea Pulmonary Venous Hypertension –mitral stenosis, left ventricular failure Congenital Heart Disease –Eisenmanger’s, PDA, ASD, VSD Vascular Obstruction –thromboembolism, systemic vasculitis

10. 5/98MedSlides.com10 Evaluation Right heart catheterization –“gold standard” for the diagnosis of PH Chest Radiography –findings depends on the duration and etiology –enlargement of the pulmonary trunk and hilar vessels, pruning of the peripheral tree,  RV –hyperinflation, flattening of the diaphragm Electrocardiogram –RV enlargement

11. 5/98MedSlides.com11 Evaluation Ultrasound –assess RV wall thickness and function –estimate pulmonary pressure from TR jet Lung Scan –rule out pulmonary thromboembolic disease Radionuclide Studies –evaluate RV function Lung Biopsy –identify interstial or collagen vascular disease

12. 5/98MedSlides.com12 Evaluation Arterial blood gas Pulmonary function test Collagen vascular serology Lower extremity venogram or compressive ultrasonography CBC and peripheral blood smear Stool and urine for parasites Polysomnogram

13. 5/98MedSlides.com13 Left-heart failure Congenital heart disease Increased blood flow Reversed shunt Passive Pulm HTN Abnormal vasoconstrictive response Hypoxemia Erythrocytosis Pulmonary Hypertension RVH / Cor Pulmonale RV Failure

14. 5/98MedSlides.com14 Pulmonary Venous Hypertension Elevated LV diastolic pressure –LV systolic or diastolic failure –constrictive pericarditis Left atrial hypertension –mitral valve disease –Cor triatriatum –left atrial myxoma or thrombus

15. 5/98MedSlides.com15 Left ventricular failure LV failure is the most common cause of pulmonary hypertension LV failure is the most common cause of right ventricular failure - attributable to failure of the muscle in the shared ventricular septum

16. 5/98MedSlides.com16 Congenital Heart Disease Pulmonary hypertension is associated with many types of CHD, and often a major determinant of it’s clinical course Large left-to-right shunt (  blood flow) –atrial septal defect, ventricular septal defect, patent ductus arteriosus Right-to-left shunt (  vasomotor tone) –hypoxia with  in red cell mass

17. 5/98MedSlides.com17 LV-RV Inter-dependance Normal Heart RV LV ED Volume ED Pressure RVLV

18. 5/98MedSlides.com18 LV-RV Inter-dependance Acute RV Distention Dilated RV Compressed “D” shaped LV LVED Volume LVED Pressure Normal RV Distended RV

19. 5/98MedSlides.com19 Thromboembolic Disease A form of occlusive pulm vascular disease –thromboembolic (U.S. and Europe) –schistosomiasis (Egypt) –filariasis (Asia) Categorization by arterial segment occlusion –small (attributable to organized thrombi) –intermediate (clots from upper legs and thighs) –large (chronic proximal thromboembolism)

20. 5/98MedSlides.com20 Respiratory Disease and Disorder Chronic Lung Disease Pulmonary Hypertension RV Dilatation and Hypertrophy Hypoxia Polycythemia Restricted Pulmonary Vascular Bed Hypercapnia Acidosis RV Failure

21. 5/98MedSlides.com21 Respiratory Disease and Disorder Intrinsic disease of lung and/or airways Interstitial fibrosis Chronic obstructive lung disease Conglomerate fibrosis, emphysema, and chronic bronchitis Collagen vascular disease Alveolar hypoventilation (sleep apnea, abnormal respiratory control, chest bellows)

22. 5/98MedSlides.com22 Miscellaneous Causes residence at high altitude hemoglobinopathies intravenous drug abuse alveolar proteinosis Takayasu’s disease

23. 5/98MedSlides.com23 References Hurst’s The Heart, 8th Edition,1994 Schlant RC, Alexander RW, O’Rourke RA, Roberts R, Sonnenblick EH Hypoxia and pulmonary hypertension in chronic bronchitis. Bishop JM. Prog Resp Res 1975, 9:10