Cardiovascular Pathology I

1. Laboratory Small Group Cases – November 6, 2008 Cardiovascular Pathology I

2. Cardiovascular Pathology ICase 1 A 55-year-old man presents to the emergency room with chest pain radiating to his left arm and dyspnea for two hours. He rates the intensity of the chest pain at 10/10 and describes it as “crushing”. For several months prior to presentation he has had a few episodes of mild chest pain which developed while climbing stairs. The pain resolved within several minutes after resting. • The patient smokes and has been told that his cholesterol is “on the high side”. • On exam, the patient is obese. He is diaphoretic and is grabbing his chest. • As part of his evaluation the ER physician orders an EKG, as well as serum myoglobin and troponin levels. • Myoglobin 106 (0-75 ng/mL) • Troponin 1.37 (<0.1 ng/mL)

3. CC: Chest Pain • Differential: 5 Life-Threatening Causes of Chest Pain • MI • PE • Tension Pneumothorax • Aortic Dissection • Esophageal Rupture

4. Pertinent Positives and Negatives • Positives: • Smoker • Obese • ST depression on EKG • Crushing pain • Myoglobin 106 (normal: 0-75 ng/mL) • Non-specific • Troponin 1.37 (normal: <0.1 ng/mL) • Specific for myocardial injury (not necessarily MI)

5. Diagnosis Acute Myocardial Infarct Coronary Atherosclerosis/Thrombosis

6. Risk Factors Associated with atherosclerosis/ ischemic heart disease Nonmodifiable Potentially controllable • Increasing age • Male gender • Family History • Genetic abnormalities • Hyperlipidemia • Hypertension • Cigarette smoking • Diabetes Mellitus • C-reactive protein

7. Describe the characteristic pathologic features in each organ Section of the left ventricle reveals transmural ischemic necrosis (emphasize staining difference between infarct and normal myocardium). The necrotic fibers have lost nuclei and cross striations. The interstitium contains neutrophils and congested blood vessels with some extravasation of RBCs. A cross section of the coronary artery reveals occlusion by a recent thrombus. The vessel wall shows modest atherosclerotic changes, including initimal fibrosis, few cholesterol clefts, focus of calcification and infiltrating macrophages.

8. Correlate the clinical findings with the pathology • Typical clinical feature of acute myocardial infarction is crushing substernal pain with radiation. • The several transient episodes of chest pain after walking up stairs represent angina.

9. Acute Myocardial infarction of left ventricle The mixture of pale myocardium (thin arrow) and hemorrhage (thick arrow) highlight the infarcted tissue. The asterix points out the non-infarcted myocardium. Right Ventricle Left Ventricle Anterior surface

10. Congested capillaries Acute inflammation myocardium 4x objective

11. neutrophils Necrotic myocytes have lost nucei and cross-striations

12. Acute Myocardial infarction of the anterior left ventricle and septum is delineated by an area of dark, red-brown hemorrhage Heart has been fixed in formalin osterior

13. Acute Myocardial infarction Cross section of the left ventricle shows an extensive, circumferential acute myocardial infarction. The asterix points out the non-infarcted myocardium.

14. Healed myocardial Infarction Cross section of the Heart (two halves):    A. Right Ventricle      B. Left Ventricle. Arrows point to healed myocardial infarction.

15. Myocardial Infarction extending to the papillary muscle Asterix denotes mitral valve leaflet. The arrow points to a partial rupture of the muscle.

16. Myocardial rupture Longitudinal section of the heart. The thick arrow points to the site of rupture of the apex of the left ventricle. The rupture occured secondary to an acute transmural infarction. The thin arrows outline the pericardial sac which is filled with blood • Left atrium  • Mitral valve   • Left ventricle

17. Large Apical Ventricular aneurysm Longitudinal section of the heart “C” represents the inlet to the aneurysm which contains a laminated thrombus (*). Notice the thin fibrotic wall (arrow) of the aneurysm. • Left atrium  • Left ventricle

18. Ventricular aneurysm Longitudinal section of the heart through the (A ) Aortic valve  (B) Left ventricle (half of the left ventricle is folded back (*) (C) Arrows delineate the thin, fibrotic wall of the aneurysm, which contains red thrombus

19. Acute coronary artery thrombosis The artery is "bread loaved" (cut in serial section)

20. calcifications media Intimal hyperplasia Thrombus RECENT THROMBUS of CORONARY ARTERY

21. Case 2 A 37-year-old Mexican male presents with fever and flank pain. Several weeks ago, he received treatment from a dentist for severe periodontal disease. He was not prescribed any medication for that procedure. His past medical history is significant for an episode of joint pains and fever when he was 10-years-old and still living in Mexico. He received some medication at that time but did not follow-up with any doctor after that. Physical exam revealed a low grade fever and a heart murmur.

22. Differential • Endocarditis • Glomerulonephritis • Pylonephritis • Renal Tumor

23. Pertinent Positives • Low grade fever • Joint Pain • Heart Murmur • Flank Pain • ECHO shows vegetation

24. Infective Endocarditis Vegetations (arrow) adhere to the cusps of the aortic valve.

25. Valvular tissue with inflammation fibrin VEGETATION VALVE Fibrin and blood

26. neutrophils fibrin

27. Describe the characteristic pathologic changes in each organ. • Section of cardiac valve with attached vegetation. The valve is distorted (thickened) by fibrosis and chronic inflammation. Acute inflammation (necrosis) is superimposed on the old pathology. A large attached vegetation is composed of fibrin, RBC’s inflammatory cells and masses of blue bacteria. • Section of the kidney demonstrates an ischemic infarct.

28. List the potential manifestations of this disorder and correlate them with thepathology. Destruction of a valve causing a murmur Emboli to multiple organs such as the brain (stroke), intestinal tract (infarction/pain) and kidney (asymptomatic or flank pain).

29. Diagnosis • Infective Endocarditis/Renal Infarct

30. Does the patient’s past medical history have any significance to his currentproblem? The patient may have had rheumatic fever as a ten year old with subsequent rheumatic valvular disease. During dental work he may have developed transient bacteremia which resulted in bacterial seeding of his deformed valve.

31. Case 3 A 27-year-old woman presents with shortness of breath, swelling of her feet and difficulty sleeping flat of 4-5 days duration. She has felt her heart beating in a “funny way” for the last two hours. She had a sore throat three weeks ago. On physical exam she has bilateral basilar lung crackles, hepatomegaly, mild ascites and pedal edema. Her heart rhythm is irregular and tachycardic.

32. Differential • Heart Failure • Right Sided • Left Sided • Dilated Cardiomyopathy • Need chest X-ray and ECHO • Myocarditis

33. Pertinent Positives • Shortness of Breath • Edema • Congestion • Ascites • Sore Throat • ECHO: Chamber Dilatation • Palpatations / Arrhythmia

34. Diagnosis • Lymphocytic myocarditis • Preceding viral infections, such as Coxsackievirus and other enteroviruses, are the most common cause of lymphocytic myocarditis in the United States

35. Inflamatory cells Myocytes

36. Lymphocytic Infiltrate with focal myocyte necrosis Normal Myocytes

37. Correlate the clinical finding with the pathology • Inflammation/necrosis of the myocardium results in injury and weakens the myocardium causing less efficient contraction. • The patient has symptoms and signs of left and right heart failure. • Inflammation and heart chamber dilatation may also induce an arrhythmia.

38. Describe the characteristic pathologic changes Infiltration of the interstitium by mononuclear inflammatory cells, predominantly lymphocytes. Focal necrosis of myocardial fibers.

39. Case 4 A 63-year-old woman presents with a left-sided headache for 2 weeks. It is throbbing and is intermittently relieved by aspirin. Two days ago she developed blurred vision and diplopia in her left eye which prompted her to see a physician. On review of systems, the woman notes that she has malaise, occasional fevers and “achy joints”. On physical exam palpation reveals a thickened, nodular and tender temporal artery.

40. Differential Diagnosis • Temporal Arteritis

41. Pertinent Positives • Achy Joints • Vision Changes • Malaise • Fever • Older Age • thickened, nodular and tender temporal artery

42. Diagnostic Plan • Biopsy of temporal artery

43. Describe the characteristic pathologic features in the structure. • Mononuclear inflammatory cells are found in the media and adventitia. • Three to four multinucleated giant cells are in the wall of the artery.

44. Correlate the clinical findings with the pathology. The headache correlates with the inflammation of the temporal artery. Malaise, fever, and joint pain represents polymyalgia rheumatica syndrome which is often seen in a patient with temporal arteritis

45. Diagnosis and Treatment Plan • Temporal Arteritis • Treatment with corticosteroids

46. Case 5 A 78-year-old man presents with sudden onset of low mid-back pain. His past history is significant for coronary artery disease and coronary artery bypass surgery. On examination, a pulsatile mass can be felt in the lower abdomen.

47. Pertinent Positives • Pulsatile mass in lower abdomen • Need ultrasound • History of coronary artery disease • Old age

48. Differential • Atherosclerotic Aneurysm of the Aorta

49. Atherosclerotic Aneurysm A medium size aneurysm arises from the aorta between the renal and inferior mesenteric arteries.

50. Describe the characteristic pathologic features of the specimen • Complicated atherosclerotic plaques • Dilatation (aneurysmal) of the aorta as a result of destruction/weakening of the media • Mural thrombus may be present