This document discusses aortic aneurysms and dissections. It covers risk factors, clinical presentations, diagnostic imaging and treatment. Key points include: thoracic aortic dissections have high mortality if undiagnosed; imaging modalities like CT, MRI and TEE are useful for diagnosis but presentations can be atypical; hypertension is a major risk factor; pain is the most common symptom but neurological symptoms, syncope or abdominal pain may occur instead.

1. AORTIC DISASTERS Ahmed Alhubaishi R3

2. OBJECTIVES: 1. Discuss risk factors for aortic aneurysm and aortic dissection 2. Discuss the clinical presentation of aortic aneurysm and aortic dissection 3. Discuss appropriate diagnostic imaging and treatment 4. Discuss can’t miss atypical presentations of dissection and aneurysm

3. WHY IS AORTIC DISSECTION AN IMPORTANT TOPIC FOR EMERGENCY PHYSICIANS TO KNOWABOUT? Thoracic aortic dissection can be extremely difficult to diagnose. Mortality rates are estimated at 50% by 48 hours if undiagnosed. Mortality rates increase by 1-2%/hour if undiagnosed. Prompt detection and therapy impact on survival rates. Knowledge of common/atypical presentations and current acute aortic disease literature will decrease the chance of a missed or delayed diagnosis

4. OUTLINES AORTIC DISSECTION Perspective Principles of disease Clinical features Diagnostic strategies Differential diagnosis Management Disposition pitfalls

5. DEFINITIONS AND ANATOMY AND CLASSIFICATION SYSTEMS aorta is composed of three layers Aortic dissection occurs when ........ Classification Stanford DeBakey acute Vs chronic [ chronic if> 2 wks]

6. Stanford - classification based on involvement of ascending aorta Type A- ascending aorta (prox. to L subclavian) Type B- descending aorta (distal to L subclavian) Debakey Type I- involves ascending aorta and the arch Type II- confined to ascending aorta Type III- confined to descending aorta distal to left subclavian IIIA- above diaphragm IIIB- below diaphragm Type A = Type I and II These require surgical repair Type B = Type III These may be treated medically

10. Stanford type B or DeBakey type III dissection distal to the subclavian artery

11. 2/3 Younger than type B Treated surgically mortality is 70% by 1 week, 80% at 2 weeks 1/3 Older patients generalized atherosclerosis hypertensive smokers Chronic lung disease Managed medically 50% two week mortality Type A Type B

12. WHERE DO DISSECTION COMMONLY OCCUR? The most common site is the first few centimeters of the ascending aorta, with 90% found within 10 centimeters of the aortic valve. The second most common site is just distal to the left subclavian artery

13. AORTIC DISSECTION RISK FACTORS Hypertension Male sex Age Pregnancy Family history Connective tissue diseaes Cocaine Turner’s syndrome Bicuspid aortic valve Iatrogenic Coarctaion Trauma Ecstasy Weight lifting Traditional Less common

14. KLOMPAS M. DOES THIS PATIENT HAVE AN ACUTE THORACIC AORTIC DISSECTION? J AM MED ASSOC 2002

15. CLINICAL FEATURES The key to making the diagnosis of this lethal aortic disease may depend on how familiar you are with well-described atypical and subtle presentations? Although textbook presentations may occasionally occur, they tend to be the exception rather than the rule. Atypical really is typical.

16. Wide range of presentaions depending on area affected and aortic branch involved Usaual presentaion is with sudden severe central tearing chest pain May present as : acute MI, acute AR, cardiac tamponade, CV collapse, limb ischemia,syncope, stroke or spinal cord syndrome Cardinal signs” pulse deficits, asymmetric BP , evolving AR murmur

17. Characteristics of Aortic Dissection from the International Registry of Acute Aortic Dissection [4] LEFT VENTRICULAR HYPERTROPHY (%) ISCHEMIA (%) NORMAL ECG (%) WIDENED MEDIASTINUM ON CXR (%) NORMAL CXR (%) PULSE DEFICIT (%) AORTIC INSUFFICiENCY MURMUR (%) SYNCOPE (%) CHEST PAIN (%) 26 15 31 62 12 15 32 9 73 All ( n = 464) 25 17 31 63 11 19 44 13 79 Type A ( n = 289) 32 13 32 56 16 9 12 4 63 Type B ( n = 175)

18. INTERNATIONAL REGISTRY OF AORTIC DISSECTION (IRAD)-STUDY BY HAGAN, ET AL. involved 464 patients with confirmed TAD. Mean age: 63 years, 65.3 % males, 62% type A dissections The findings: pulse deficit 15 % aortic murmur 31.6 % normal chest x-ray 12 % absence of mediastinal widening 34 % syncope 12 % painless 2.2%

19. CONCLUSIONS FROM THIS STUDY: (1) Classic findings of aortic dissection are often absent (2) Don’t rely on textbook presentations

20. KLOMPAS M. DOES THIS PATIENT HAVE AN ACUTE THORACIC AORTIC DISSECTION? J AM MED ASSOC 2002

21. PRESENTATIONS REPRESENT COMMON, RECURRING THEMES AMONG MISSED AORTIC DISSECTION CASES (1) TAD and Stroke consider TAD in the following scenarios: Chest pain and any neurologic symptoms (CVA, dysphagia, etc.) Chest pain and limb paresthesia (2) Painless TAD and Syncope Add TAD to your differential diagnosis of unexplained syncope

22. CONT. 3) TAD and Paralysis Consider TAD in the following scenarios: Chest pain and limb (particularly lower extremity) weakness or paresthesia Chest pain and spinal cord syndromes Unexplained lower extremity weakness (4) TAD and Myocardial Infarction

23. (5) Isolated Abdominal Pain Consider TAD in the following scenarios : Unexplained abdominal pain in the presence of hypertension Combination of chest and abdominal pain Abdominal pain and cocaine use Unexplained abdominal pain and an “ill-appearing” patient (6) TAD and “the other complaint’’ Consider TAD under the following circumstance: Chest pain combined with “the other complaint” (especially neurologic symptoms)

24. (7) Cough, Hoarseness, and SVC Syndrome (8)Young patients with TAD (9) pt with Congestive Heart Failure Consider TAD in patients with new onset CHF

25. Januzzi, JL et al. Acute Aortic Dissection Presenting With Congestive Heart Failure: Results From the International Registry of Acute Aortic Dissection. J Am Coll Cardiol, 2005 Patients who present with CHF symptoms secondary to acute aortic dissection are much more likely to have none or mild pain compared to patients with aortic dissection without CHF symptoms

26. THINGS TO BE DOCUMENTED: Consider documenting the following in all chest pain patients: Risk factor profile for TAD (HTN, cocaine, family history, etc) Blood pressure in both arms (equal) Pulses (symmetric) Absence of aortic murmur Absence of marfanoid body habitus

27. LIMITATIONS OF THE PHYSICAL EXAMINATION Bilateral BP measurement 19% of the population may have arm differences greater than 20 mm Hg Von Kodolitsch et al. did show that a BP differential > 20 mm Hg was an independent predictor of TAD 50% of patients who present with TAD are hypertensive Aortic murmur: 1/3 of patients with TAD Pulse deficit: 15% of cases of TAD Pitfall: Over-reliance on a “classic” presentation for diagnosis of AD

28. DIAGNOSTIC STRATEGIES Gold standards

29. -- Sensitivities and Specificities of Imaging Modalities for Diagnosing Aortic Dissection ( From Shiga T, Wajima Z, Apfel CC, et al: Diagnostic accuracy of transesophageal echocardiography, helical computed tomography, and magnetic resonance imaging for suspected thoracic aortic dissection: Systematic review and meta-analysis. Arch Intern Med 166:1350–1356, 2006 .) MRI HELICAL CT TEE TEST 98 100 98 Sensitivity (%) 98 98 95 Specificity (%)

30. Sens Spec Advantages Disadvantages TTE 80% 95% Too many false negatives TEE 98% 90-100% Rapid (10-30 minutes) Bedside test Inexpensive ID’s site of tear in 75% No contraindiciations No radiation/contrast Gives info about aortic regurgitation Tough to see ascending aorta CT scan 95% 90-100% Rapid (20-40 minutes) Low FP and FN rates Dynamic scanning detects different filling rates Expensive Uses contrast Outside ED (no monitor) No info re: regurg MRI 98% 98% Non-invasive No radiation/contrast Gives excellent detail of dissection, including branches Slow (up to 75 minutes) No monitoring Contraindications Expensive Aorto-graphy 88% 95% Intimal tear seen in 56% Identifies AI, coronary and carotid extension Not as sensitive as MRI or TEE Needs contrast Invasive Slow (1-2 hours) Thrombosed lumen may be obscured

31. WHEN TO USE THE ABOVE MODALITIES? Hemodynamically unstable- TEE Surgeon requires definitive anatomical delineation- CT, MRI, Aortography R/O dissection for MI- TEE would be adequate Hemodynamically stable- CT, MRI,

32. Computed tomography scan demonstrating the true lumen and false lumen

38. ECG PITFALLS ECG commonly shows LVH, reflecting long-standing hypertension ST-T changes or heart blocks can occur Note that 10-40% with dissection may have ECG changes suggestive of MI Unclear if due to dissection or possible coronary dissection ST changes imply a much worse prognosis

40. 12 lead ECG of a young patient with confirmed proximal TAD. The ECG shows inverted T-waves and ST-depression in the inferior leads. During operative repair, the right coronary ostia was found to be occluded.

41. CXR PITFALLS abnormal in 80-90% of cases Mediastinal widening- in 75% “ Calcium sign Aortic double density Disparity in caliber between ascending and descending aorta Localized bulge on the aorta Obliteration of the aortic knob NG tube, trachea or ETT displaced to the right Pleural effusions- common and usually on the left

42. HAGAN P, NIENABER CA, ISSELBACHER EM, ET AL. THE INTERNATIONAL REGISTRY OF ACUTE AORTIC DISSECTION (IRAD): NEW INSIGHTS INTO AN OLD DISEASE. J AM MED ASSOC 2000 Pitfall : Use of the chest X-ray to exclude the diagnosis of AD

45. Myocin heavy-chain concentrations D-dimer levels soluble elastin fragments newer tools that may be helpful to the diagnosis of aortic dissection and await prospective clinical trails to evaluate their usefulness

46. D dimer Not ready for prime time as a rule-out strategy Sodeck, et al. D-dimer in ruling out acute aortic dissection: a systematic review and prospective cohort study. European Heart Journal 2007

47. DDX acute MI pulmonary embolus Pericarditis CCF … .. etc

48. MANAGEMENT ABC’s above all else Ultimately, a transfer to a hospital with a CVT surgical service should be done once patient is stable enough. Resuscitate with fluids or blood as needed if hypotensive

49. BLOOD PRESSURE CONTROL IS THE KEY TO MANAGEMENT Maintain systolic blood pressure between 100- 120 mmHg and reduce force of cardiac contraction Nitroprusside 50-100mg in 500cc D5W at rate 0.5-3 ug/kg/min (titrate to BP) **** Increases heart rate, so if given alone it may worsen the dissection B-Blockers Propanolol- used inconjunction with Nipride 1 mg IV every 5 minutes (max 0.15 mg/kg) Later given as 2-6mg every 4-6 hours Esmolol- also given with Nipride 500 mg/kg over 1 min, then infusion of 50 to 150 mg/kg per minute. Labetalol- used as a single agent (α-effects attenuates heart rate) Bolus of 5-20 mg, then infusion of 1-2 mg/min

50. DISPOSITION Surgery for type A not type B hospital mortality in type B dissections treated without surgery is 15-20%, which is comparable to or better than the operative mortality rate. OR mortality rate is decreasing for type B though OR mortality rate for type A is about 7% (and decreasing)

51. HOW CAN WE DECREASE CHANCES OF MISSING THE DIAGNOSIS OF TAD? In reality: no way that every case of A.D can be diagnosed in ED Know the subtle and atypical presentations well. Think beyond classic textbook descriptions and think of TAD more often Perform a detailed risk factor profile for TAD on every chest pain patient

52. CONT. Decrease your own threshold to obtain CT scans in chest pain patients Approach every chest pain patient as if they could have a TAD and convince yourself the patient doesn’t have it. • Realize that young patients without connective tissue disease can have TAD

53. ABDOMINAL AORTIC ANEURYSM ■ A true aneurysm involves all three layers of vessel wall. ■ A false aneurysm or pseudoaneurysm communicates with the vessel lumen, but is contained only by adventitia or surrounding soft tissues.

54. Types of aortic aneurysms

55. (AAAs) is true aneurysms involve the infrarenal aorta. aortic diameter >3 cm = AAA. An AAA of any size can rupture, but those >5 cm are more likely to rupture. size is the most important factor in determining rupture risk The most common location of rupture  retroperitoneum Rupture is associated with an 80–90% overall mortality

56. PRIMARY RISK FACTORS FOR AAA Increasing age > 65 Family history ,? Genetic ( 1 st degree relatives have 10-20 times the risk) Atherosclerotic risk factors ie htn ,dm, smoking,cad,male Other predisposing factors include infection, trauma, connective tissue disease, and arteritis.

57. Table 84-1 -- Prevalence of Abdominal Aortic Aneurysms (AAAs) in Selected Risk Groups INCIDENCE (%) GROUP 2–4 Autopsy subjects aged 50 years or old 5,6] 5–10 Men aged 65 years or older [4,7] 10–15 Patients with coronary artery disease [8] or occlusive peripheral vascular disease [9,10] 20–30 Brothers of patients with AAAs [11,12]

58. SYMPTOMS ■ Most aneurysms are asymptomatic when discovered (60-80%)and become symptomatic when expanding or ruptured. ■ Acute pain in abdomen, back, or flank [ 75% ] ■ Nausea and vomiting ■ Syncope or near syncope urologic symptoms 10%

59. EXAM ■ Vital signs may be surprisingly normal. ■ Hypotension and shock if rupture with significant blood loss ■ Abdominal tenderness, distension, or pulsatile abdominal mass [75% above umbilicus] ■ Evidence for retroperitoneal hematoma ■ Periumbilical ecchymosis ( Cullen’s sign) ■ Flank ecchymosis ( Grey-Turner’s sign) ■ Massive GI bleed if rupture into GI tract (aortoenteric fistula) ■ High-output heart failure if rupture into vena cava (aortocaval fistula)

60. Triad of abdominal pain, hypotension, pulsatile abdominal mass = AAA until proven otherwise, although triad is rare. Kiell CS and C.B. Ernst, Advances in management of abdominal aortic aneurysm, Adv Surg 26 (1993) ,

61. Exam – limited sensitivity Improves as AAA enlarges Worsens with obesity Unknown value in rupture Do not use to exclude AAA Lederle FA, Simel DL. The rational clinical examination. Does this patient have abdominal aortic aneurysm? JAMA. 1999 Jan 6

62. DIAGNOSIS The diagnosis should be suspected in any patient >50 years old presenting with abdominal pain, flank pain, or hypotension. Delay in diagnosis of these conditions is common AAA rupture (30% misdiagnosed initially)

63. ABDOMINAL X RAY Abnormalities seen in 2/3 to ¾ of cases But AXR rarely ordered for AAA Retrospectively apparent in 90% Most common signs are wall calcifications and a paravertebral soft tissue mass, both seen in 65% Other signs include loss of psoas or renal outlines, renal displacement, and occasionally a properitoneal flank stripe AXR cannot be used to rule out an AAA

64. Anteroposterior ( A ) and lateral ( B ) views of large abdominal aortic aneurysms with calcification of the aortic wall

65. Ultrasound 100% sensitive when aorta is visualized Modality of choice in the unstable patient May not be able to identify rupture, site of leak, or retroperitoneal hematoma

66. Cross-sectional ultrasound of a 6-cm abdominal aortic aneurysm. Note mural thrombus and eccentrically shaped patent lumen .

68. Widely cited as sensitive for AAA (98%) But not for rupture Combination: US confirmation of aneurysm abdominal pain unstable hemodynamics 95% sensitive in determining need for emergency surgery for AAA Costantino TG, Bruno EC, Handly N, Dean AJ. Accuracy of emergency medicine ultrasound in the evaluation of abdominal aortic aneurysm. J Emerg Med. 2005

69. CT - Highly sensitive - Requires stable patient for transport -Better than ultrasound at detecting rupture and retroperitoneal blood MRI or aortography are rarely indicated in the ED. Sharma U, Ghai S, Paul SB, Gulati MS, Bahl VK, Rajani M, Mukhopadhyay S. Helical CT evaluation of aortic aneurysms and dissection: a pictorial essay. ClinImaging. 2003

70. Computed tomography scan of ruptured abdominal aortic aneurysm, with calcification of the aortic wall and intraluminal thrombus. The patent lumen enhances with the administration of contrast material, but the periaortic hematoma ( arrow ) does not .

72. COMMON MISDIAGNOSES IN PATIENTS WITH RUPTURED ABDOMINAL AORTIC ANEURYSMS Renal colic “ Acute abdomen ” Pancreatitis Intestinal ischemia Diverticulitis Cholecystitis Appendicitis Perforated viscus Bowel obstruction Musculoskeletal back pain Acute myocardial infarction “ Acute abdomen ” Renal colic Musculoskeletal back pain Acute myocardial infarction

73. *** Anemia in conjunction with chronic back pain- think AAA ‘ Mimic’ Reasons why Pancreatitis Pain pattern is similar Bowel obstruction If duodenum is stretched over AAA Diverticulitis Vague LLQ pain occasionally seen in AAA Obstructive jaundice Rare- if CBD is compressed Renal colic AAA compresses ureter Hematuria occurs infrequently (more when AV fistula present) Testicular pain Hemorrhage to scrotum Extension to Iliac vessels with compression of inguinal canal Inguinal hernia Extension to iliac vessels Hip pain Extension to iliac vessels Sciatica/Femoral nerve pain Compression of femoral nerve in retroperitoneum Ischemic bowel Vague abdominal pain, dull Pyelonephritis Back/flank pain Chronic abd. Pain NYD 10% live >6 weeks after onset of symptoms

74. TREATMENT Ruptured aneurysms require immediate surgical intervention with operative or endovascular repair. 50% operative mortality Fluid and blood resuscitation: To SBP 90–100 mmHg. Thoracotomy with cross clamping of aorta: If severe hemodynamic compromise or cardiac arrest

75. CONT. Asymptomatic aneurysms can be scheduled for repair based on aneurysm size and patient comorbidities. Endovascular repair with stent graft is increasingly used.

76. surgically repaired ruptured AAA, mortality 46% Once in ED, early diagnosis decreases mortality from 75 to 35% Wainess RM, Dimick JB, Cowan JA Jr, Henke PK, Stanley JC, Upchurch GR Jr. Epidemiology of surgically treated abdominal aortic aneurysms in the United States, 1988 to 2000. Vascular. 2004 Jul-Aug

77. COMPLICATIONS Rupture Atheroembolism: Microemboli from atherosclerotic aneurysms Lodge in distal small vessels “ Blue toe syndrome” is classic presentation. Can also occur from nonaneurysmal atherosclerotic plaques Graft complications ■ Graft infection ■ Secondary aortoenteric fistula ■ Endoleak: Leak outside of graft lumen, but within existing aneurysm sac (continued risk for AAA rupture!)

78. Thank you