Aortic Dissection and AneurysmsDr Syed Asmar Yazdani, MDCTS

Abdominal Aortic Aneurysms (AAA)Risk factorsElderly (>60)Familial trend (18% with 1 relative)Connective Tissue D/O (Marfans)Other aneurysmsAtherosclerosis (HTN, Lipids, smoking, DM)

AAAPathogenesisIntima infiltrated by atherosclerosis and thinned media.Possible intraluminal thrombus and adventitia infiltrated by inflammatory cells

AAAAverage rate of growth 0.25-0.5 cm per year.Larger aneurysms extend more rapidly than smaller ones. (LaPlace law)

AAAClinical FeaturesSyncope (10-12%)Back and/or Abdominal Pain severe and abrupt, ripping or tearing sensation (50%)Shock intraperitoneal rupture, massive blood lossSudden death

AAAPhysical ExamPain on palpation or notRetroperitoneal hematomaCullen sign (periumbilical ecchymosis)Grey-Turner sign (flank ecchymosis)Scrotal hematoma or inguinal mass (blood dissecting to these areas)Iliopsoas signFemoral nerve neuropathy

AAAFound aneurysms refer to follow up>5cm diameter increased chance of rupture

AAADiagnosisIncludes differential diagnoses of syncope, abd pain, CP, back pain and shock.If with combo of two or more think aortic dz.

AAARadiologic EvaluationShould not delay operative treatment!!Plain abd film (calcified bulging)US (bedside, up to 100% sensitive, not reliable to detect rupture)CT (with IV contrast only if stable)MRI

AAAED TreatmentUrgent surgical consultMake diagnosis & assist rapid transfer to OR2 large bore IVsCardiac MonitorO2? Blood transfusionIV fluid resuscitation controversial amount b/c too much can be harmfulRADIOGRAPHIC STUDIES ONLY IF UNLIKELY TO HAVE RUPTURED AAA!!!

AAA of patients with ruptured AAA who reach the OR die!

A Bit About Thoracic Aortic AneursymPresenting symptoms include esophageal, tracheal, bronchial, or even neurologic disorders.If it erodes to adjacent structures it is immediately fatal!!

Aortic DissectionPathogenesisProminent cause of sudden deathPresents with severe abd., chest, and back painViolation of intima that allows blood to enter media and dissect b/w intimal and adventitial layersCommon site is ascending aorta at ligamentum arteriosum

Aortic DissectionCommon presenting groups>50 yoa with HTN2/3 maleMarfans syndromeCongenital heart diseasePregnancy

Aortic DissectionStanford ClassificationType A -involves ascending aortaType B involves descending aortaDeBakey ClassificationType I ascending, arch & descending aortaType II ascending onlyType III descending only

Aortic DissectionClinical Features>85% abrupt, severe pain in chest or b/w scapula50% ripping or tearingPain in anterior chest ascending aorta (70%)Back pain (less common) descending aorta (63%)If dissection into carotid classic neuro symptoms

Aortic DissectionClinical Features40% with neurologic sequelae (ex. paraplegia)Nausea, vomiting, diaphoresisMost have sense of impending doom!

Aortic DissectionPhysical ExamUsually normal heart and lung examMay have aortic insufficiency

Aortic DissectionPhysical ExamPericardial tamponade (muffled heart tones, JVD, pulsus paradoxus)Hoarseness (compression of recurrent laryngeal nerve)Horners Syndrome (compression of superior cervical sympathetic ganglion)

Aortic DissectionDiagnosisIschemic end-organ manifestation such as MI, pericardial dz, pulmonary d/o, stroke, SCI, musculoskeletal dz of extremities, intraabdominal ischemia.Can change location with time as dissects.

Aortic DissectionThoracic Dissection90% have abnormal CXRWidened mediastinumAbnormal aortic contourPleural effusionDeviation of trachea, mainstem bronchi, or esophagusIntimal calcium visable & distant from edge (calcium sign)

Aortic DissectionDiagnosisCT 83-100% sensitive 87-100% specificUse spiral CT with IV contrastWill not give anatomic details of arterial branches or aortic valve competence.Modality of choice in unstable patient

Aortic DissectionDiagnosisAngiography Gold standardShows all anatomy and involvement94% specific88% sensitiveTEE97-100% sensitive97-99% specificEsophageal dz contraindication

Aortic DissectionIn contrast to ruptured AAA, SUSPECTED DISSECTIONS MUST BE CONFIRMED RADIOLOGICALLY PRIOR TO SENDING TO OR!!!

Aortic DissectionED TreatmentTreat hypertension-blockerEsmolol 500g/kg IV bolus over 1 minute then 50-150 g/kg minuteMetoprolol 5mg q2min x3 IV then 2-5mg/hr Propranolol 20mg IV then 40mg, 8-mg q10min to 300mg totalCalcium channel blocker if -blocker contraindicated

Aortic DissectionED TreatmentVasodilatorNitroprusside 0.3 g/kg/min IVSurgeryOR for ascending aortic dissectionDescending aortic dissection worse surgical risks controversial for repair

Any Questions????

Questions1. A patient with a suspected aortic dissection should be immediately tranferred to OR without radiographic studies.A. TrueB. False

2. Females are more likely than males to develop aortic dissection.A. TrueB. False3. Dissection of the ascending aorta only is DeBakey classificationA. Type IB. Type IIC. Type IIID. Type AE. Type B

4. Patients with a ruptured AAA can present with all of the following symptoms exceptA. ShockB. SyncopeC. Sudden deathD. Nausea and vomitingE. Headache

5. Which of the following radiologic modalities is considered the gold standard for diagnosing an aortic dissection?A. CTB. MRIC. TEED. AngiographyE. CXR

Answers1. B2. B3. B4. E5. D