Aortic Emergencies

Dr. Margriet Greidanus, CCFP (EM)

September 4, 2008

Outline• Aortic Dissections

– Epidemiology and natural history– Risk factors– Classification– Presentation– Clinical Findings– Tests– Treatment

• Abdominal Aortic Aneurysm– Risk Factors– Clinical Presentation– Diagnosis and Management

• Aortovenous Fistula• Aortoenteric Fistula

Jonathan Larson, the author of the broadway musical rent died at the age of 35 from a type A thoracic aortic dissection. He was seen three separate times in an emergency department in New York before he was found dead in his apartment by his roommate. Mr. Larson presented initially with a complaint of severe chest pain and was diagnosed with food poisoning, despite no symptoms of nausea, vomiting, or diarrhea. What is interesting is that his chest x-ray showed a significantly widened mediastinum. He later presented with chest and back pain. He was quoted as saying, “You’d better call 911. I think I am having a heart attack.” Mr. Larson was later diagnosed as having Marfans disease.

• I was 27, on Sept 2 I had my girl 5 weeks early. During my delivery I was given extra fluids and antibiotics for a heart murmur I had been diagnosed with in college. My epidural ran out-half way through the labor (24 hours) and I remember screaming and cursing at the nurses about the pain I was in. After discharge, I had to go back to the hospital every 2 hours for feeding. I instead of losing weight after delivery, I seemed to be gaining. I was tired, looked awful and had terrible pain in my back. I had to sleep sitting up. I had a hard time breathing and was coughing a lot. I reached a point where I could not breathe and could not talk from coughing, and he took me back. I was in congestive heart failure-one step away from a ventilator with 64% oxygen. I remember everyone moving out of my way in the emergency room- I must have looked awful and I don't remember much after that except that I was being flown to John Hopkins for emergency surgery.

October 27, 2004 started out like any other day. I am a part-time reading teacher at an elementary school! The day proceeded as normal, I ate lunch in the teacher's lounge, and walked down to the cafeteria to pick up "my" class.

On the way up the steps, I felt a terrible burning sensation in my chest and moderate pain. I thought it strange that a PB&J would cause such heartburn, but I tried to ignore it. With every step I took, the pain intensified. I felt as though someone had opened my chest with a chainsaw and lit a blowtorch and was aiming it directly into my abdomen and chest. I knew something was majorly wrong as I walked to the nurse's office and my left leg had gone numb. My father had a heart attack at the age of 41, and I assumed the same thing was happening to me, and I was only 28.

Epidemiology

• 2-3x more common then AAA ruptures• 2.6 to 3.5 per 100,000 person-years• Males >Females• Typically 50-70 years old• Average age 60 in men, 67 women• Mortality rates are estimated at 50% by 48

hours if undiagnosed.• Mortality rates increase by 1%/hour if

undiagnosed.

Risk Factors• Hypertension - present in 70-90%• Age• **Family History**• Connective tissue disorders

• Marfans - esp if pregnant• Ehlers-Danlos• SLE

• Pregnancy (3rd trimester)• Bicuspid Aortic valveLess Common• Congenital heart disease - coarctation (Turner’s)• Stimulent use• Infectious disease (syphilis, endocarditis)

The GREAT MIMICKER“In fact, difficulty in diagnosis, delayed diagnosis or

failure to diagnose are so common as to approach the norm for this disease even in the best hands, rather than the exception”J. Elefteriades Cardiology 2008

• Myocardial ischemia due to an acute coronary syndrome with or without ST segment elevation

• Pericarditis• Pulmonary embolus• Aortic regurgitation without dissection• Aortic aneurysm without dissection• Musculoskeletal pain• Mediastinal tumors• Pleuritis• Cholecystitis• Atherosclerotic or cholesterol embolism• Peptic ulcer disease or perforating ulcer• Acute pancreatitis

Presentation

• Pain - sharp, tearing, abrupt onset– 15% have typical presentation

• Based on location of the dissection– CVA,visual changes– Paraplegia– Pulseless extremity– MI/CHF/Pulmonary edema/Temponade– Abdo pain (mesentaric ischemia) nausea/vomiting– Syncope– Flank pain (oliguria/hematuria)

International Registry of Aortic Dissection (IRAD)

International Registry of Aortic Dissection (IRAD)-Study by Hagan, et al. that 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%

Atypical Presentations

• Chest pain and any neurologic symptoms (CVA, dysphagia, etc.)– TAD and Stroke-Neurologic deficits 18-30% of cases.– 5-10% have TIA/CVA symptoms

• Chest pain and any neurologic symptoms (CVA, dysphagia, etc.)

• Chest pain and limb paresthesias

Atypical Presentations

• Chest pain and limb (particularly lower extremity) weakness or paresthesia– TAD and Paralysis-Spinal cord involvement -10% of

cases • perfusion abnormalities in the greater radicular artery (artery

of Adamkiewicz), a large branch from the aorta that perfuses a large portion of the thoracic and lumbar spine.

• Chest pain and spinal cord syndromes: transverse myelitis, progressive myelopathy, paraplegia, quadriplegia, and anterior spinal cord syndrome.

Atypical Presentation

• Painless TAD and Syncope-Patients– IRAD study, 2.2% of TAD cases were painless.

– Other studies have shown that as many as 15% of TAD cases are painless.

– Results in either no perfusion to the brain or temponade

• Absence of pain does not rule out the diagnosis. Add TAD to your differential diagnosis of unexplained syncope.

Atypical Presentations

• TAD and Myocardial Infarction

• Occurs in <1% of MIs

• 1-7% of cases of TAD– Due shear forces against the right lateral aortic

wall, right coronary ostial occlusion and malperfusion is more common.

Atypical Presentations

• Isolated Abdominal Pain– Given the frequency of abdominal pain ED visits and

the extensive differential diagnosis, picking up TAD-associated abdominal pain may be difficult.

• 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

Clinical Findings• Unequal BPs in arms

• 19% of the population may have arm differences greater than 20 mm Hg. • Von Kodolitsch et al. did show that a blood pressure differential > 20 mm

Hg was an independent predictor of TAD

• Unequal or absent pulses• Focal neuro deficits• Hypertensive/Hypotension/Pseudo low BP (periph pulses

decreased but central arterial pressure is normal or high)– only about 50% of patients who present with TAD are

hypertensive. The other half are either normotensive or hypotensive.

• Aortic regurgitation - diastolic murmur

Tests• ECG - not useful -

– 15% show ischemia, 26% LVH, no abnormalities 31%, other findings include non-specific ST changes

• D-Dimer– New literature showing a neg d-dimer rules out– Case reports of dissections with negative D-Dimers– Can’s use to rule out dissections … yet

• CXR• IRAD study - 12 % of patients with TAD had a normal chest x-ray, 37 % had no

evidence of mediastinal widening.

• CT - Test of choice• TEE• MRI

Classification

• Debakey– I-IV

• Stanford– Type A

• 67%

– Type B

Treatment• International Registry of Acute Aortic Dissection

(IRAD) - review of 464 patients• Type A - 72 percent treated surgically • Type B - 20 percent treated surgically• Type B - typically medical therapy

– lowering the blood pressure ~ 100 systolic• Esmolol if BP low (short half life)• Labatolol • Nitroprusside drip

– decreasing the velocity of LV contraction• both decrease aortic shear stress • minimize the tendency for propagation of the dissection.

Why we miss it• Because it is a very atypical presentation

– Can occur in the VERY young (>15)

• Failure to evaluate risk factors for TAD.• Failure to integrate patient complaints

– A review of missed TAD literature highlights the fact that many cases have been missed because the treating physician failed to address all of the patient’s complaints.

– EP may assign a diagnosis that simply doesn’t make sense.

• The “obvious miss” and inadequate knowledge base.• Inadequate knowledge of atypical and subtle

presentations

How can we avoid the lawsuit

• Risk factor profile for TAD (HTN, cocaine, family history, etc)

• Blood pressure in both arms (equal)

• Pulses (symmetric)

• Absence of aortic murmur- diastolic, best heard leaning forward

• Absence of marfanoid body habitus

Abdominal Aortic Aneurysms

• Risk Factors

• Presentation

• Diagnosis and Management

Risk Factors

• Advanced age (>75% older then 60

• Male

• Family history

• Hypertension

• Smoking

• History of CAD/PVD

Presentation

• Syncope +/- back pain• Vasculopath with new back pain or a CHANGE in

back pain• Flank pain • Back of thighs or buttock pain• Abdo pain • Within first 24 hours• If hypotensive they have 50% survival

Diagnosis

• If you clinically think they have a AAA - call the surgeon, don’t wait for CT to call. If stable then do a CT

• X-rays - only useful if large calcified aorta and you see a shadow beyond it (eggshell sign)

• U/S can see aneurysm but can’t tell if it is leaking. – EDE - you need to see infrarenal Aorta

Management

• Call the surgeon

• 2 large bore IV

• Type and Cross for 10 units

• Fluids or blood for hypotension

• Treat pain if hypertensive

AAA Pearls

• Can present EXACTLY like renal colic including hematuria (3-10%)

• 10-20% of renal colic can present with no hematuria

• Equal femoral pulses does not rule OUT a AAA

Aortovenous fistula

• Aorta and inferior vena cava fistula – engorged lower leg veins– Loud bruit in abdo

Treatment

- interventional radiology

Aortoenteric Fistula

• VERY BAD

• Risk factors– Recent aortic surgery

• Signs and Symptoms– Horrible exsanguinating GI bleed– Fever– Back pain