A rare case of acute aortic dissection secondary to a penetrating aortic ulcer in the ascending aorta

Sanjanaa, Aslesha Shethb,*

a1st year MRCEM Resident, Kauvery Hospital, Chennai, Tamilnadu, India bConsultant and Clinical Lead, Emergency Medicine Department, Kauvery Hospital, Chennai, Tamilnadu, India

*Correspondence: Email: draslesha@kauveryhospital.com

Case presentation

A 63 years old lady who is a known hypertensive on ayurvedic treatment, presented to the emergency room (ER) with the history of sudden onset chest pain radiating to back and profound giddiness with three to four episodes of non-projectile, non-bilious, vomiting since that morning associated with profuse sweating.

Patient had history of fever for one day, one week ago, which settled with oral paracetamol. She was initially treated at an outside hospital with IV analgesics and treated as gastritis. Due to persistence of symptoms, patient came here for further management (Tables 1–2).

On Examination Table 1.
Laboratory data on examination

HR 110
BP 70 SBP
RR 16/min.
SP02 91% RA
Temp Normal
CBG 228
GCS 14/15
  1. Airway: Patent and Self maintained
  2. Breathing: B/L air entry (+), chest clear
  3. Circulation:
    1. Peripheral pulses feeble, cold peripheries.
    2. Patient was extremely diaphoretic,
    3. Heart sounds = S1 S2 heard, muffled heart sounds
    4. Dilated engorged neck veins present.

Table 2. Blood pressure of all four limbs

Right (mmHg) Left (mmHg)
Upper limb 90/60 60/50
Lower limb 70/50 70/40
  1. Disability: Moving all four limbs, GCS = E3 V5 M6 (14/15), B/L PERL (3mm), No Nystagmus.
  2. Exposure: No external injuries.

Investigations

Table 3. Venous Blood Gas Analysis

pH
PcO2
pO2
HCO3
Base Excess
Glucose
Lactates
7.198
49.0
15.5
18.6
-9.0
397
7.05

Table 4 CHEM8

Na
K
Cl
Tco2
Glucose
BUN
Creatine
Hb
136
3.3
100
20
346
12
0.8
9.5

2.2.1. ECG

Normal Sinus rhythm, HR -109 bpm

2.2.2. ECHO

1
2
3
4
5

IVC full. Hemopericardium with blood clots. RV Diastolic Collapse and severe LVD

Treatment given in the ER

  1. Patient in supine position with leg end elevation.
  2. Two wide bore IV cannula secured &SpO2 maintained > 94%.
  3. Continuous cardiac monitoring done.
  4. In the view of BP not recordable = IV fluids – normal saline 500 ml + 500 ml IV stat was given, patient still in hypotension, hence double strength ionotropes support – IV noradrenaline was started at 5 ml/h and tapered to maintain MAP of 65.
  5. Urgent bloods sent – CBC, LFT, PT, INR, serology and blood grouping and typing.
  6. Urgent blood reservation of four units of PRBC & cross matching.

Our provisional diagnosis of probable acute aortic dissection with pericardial tamponade and obstructive shock was made.

Urgent cardiology opinion was obtained and patient was then shifted to CT scan for urgent CT Aortogram.

2.3.1. CT Aortogram:

21
22
23
24
25
26
27
28

Hemopericardium with rupture of the intramural hematoma. Acute aortic dissection involving ascending aorta root, arch of aorta, thoracic and descending aorta, abdominal aorta and aortic bifurcation – DeBakey Type I.

There was a long segment hyperdense circumferential intramural hematoma noted in ascending aorta, arch and descending thoracic aorta up to the junction of mid and lower 3rd with maximum thickness of the intramural hematoma noted in the ascending aorta measuring about 10 mm. Penetrating ulcer from the anterior wall of ascending Aorta approximately about 3.0 cm proximal to the innominate region of origin of brachiocephalic artery with significant pericardial collection. Periaortic hematoma extending from ascending Aorta to descending thoracic Aorta.

CT Brain

Age related small vessel microangiopathy and chronic lacunar infarcts in bilateral external capsules.

CT Abdomen

Minimal free fluid in the abdomen.

In view of acute aortic dissection with pericardial tamponade and obstructive shock. Urgent CTVS opinion was obtained and then the patient was shifted immediately for emergency ascending aorta replacement with 26mm Dacron graft.

Patient was transfused with multiple units of blood – PRBC, whole blood, platetlets and FFP. Patient was extubated on post op day 3. As Patient was hemodynamically stable and recovered well, she was discharged on sixth POD.

Intra – Operative Images

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33

Discussion

Penetrating ulcer of the ascending aorta is a very rare pathological entity with known potential for progression towards intramural hematoma or dissection.

Penetrating atherosclerotic ulcers (PAU) are a pathology that involves the aortic wall. Along with aortic dissection and aortic intramural hematoma they can form the spectrum known as acute aortic syndrome.

Indications for surgery are not completely standardized either and several authors have claimed that conservative management might offer a safer alternative in uncomplicated cases. On the other hand, it has been clearly established that penetrating ulcers can promote major aortic complications such as intramural hematoma and acute aortic dissection whose risk of rupture is much higher when the ascending aorta is involved. Hence although rare, it can be postulated that perforating ulcers of the ascending aorta carry worse prognosis than their counterparts located to the descending aorta and should probably be treated more aggressively. Open repair can be performed either by resection and patch reconstruction or by segmental replacement of the aorta with a Dacron tube. The latter technique was preferred in this patient whose ascending aorta was slightly increased in diameter. Recently endovascular approaches have been successfully applied to descending aortic ulcers and might as well be used for ascending aortic lesions in selected cases.

Although its vascular wall comprised three layers, the aortic lesion was labelled as a penetrating ulcer due to its similarities with previously published observations. Concerning the pathophysiology, as opposed to most reports, many cases demonstrate that penetrating ulcer can occur without any calcification plaque or sign of atheroma.

A penetrating ulcer, also called penetrating atherosclerotic ulcer, is a rare condition that most commonly develops in the descending aorta. It occurs when plaque in the aorta (from atherosclerosis) forms ulcers that penetrate the aortic wall. By damaging the aortic wall, penetrating ulcers put patients at risk for aortic dissection or rupture. Although the appearance of a penetrating ulcer may resemble an aortic aneurysm or dissection on imaging scans, its cause, atherosclerosis, is unique.

Patients who develop a penetrating ulcer usually have atherosclerosis (hardening of the arteries), hypertension (high blood pressure), and back or chest pain. Many are current or former smokers. Diagnosis of a penetrating ulcer may be done through CT scan, MRI, and or transesophageal echocardiography (TEE).

Although classic aneurysms located in the thoracic aorta are not usually at high risk of rupture, penetrating ulcers may require surgery. Most commonly, this disease is treatable with minimally invasive endovascular stent procedures.

Epidemiology

Typically, penetrating atherosclerotic ulcers are seen in older male patients with a history of hypertension (up to 92%), smoking (up to 77%) and coronary artery disease (up to 46%) as well as chronic obstructive pulmonary disease (24-68%) [1].

Penetrating atherosclerotic ulcers account for ~7.5% (range 2.3–11%) of all cases of acute aortic syndrome 1. In ~50% (range 42–61%) of cases, there are concurrent aortic aneurysms, most often in the abdomen 1.

History and etymology

They were first described as a distinct clinical and pathological entity by (Stanson et al., 1986).

Clinical presentation

Typically, patients present with symptoms of an acute aortic syndrome, namely acute intense chest pain, often described as tearing, ripping, migrating or pulsating [2].

Some of the patients with penetrating atherosclerotic ulcers are asymptomatic and the diagnosis is made incidentally. In the previously cited article, they cite the Mayo Clinic series in which just 75% of the patients had been symptomatic.

Pathology

The term “penetrating atherosclerotic ulcer” describes an ulcerating atherosclerotic lesion that penetrates the intima and progresses into the media. In the early stages, the lesions just ulcerate the intima and are often asymptomatic. With further progression, they ulcerate the media and lead to a hematoma of variable size within the media [3].

The penetrating atherosclerotic ulcer can resolve completely or stay stable, but they can also lead to aortic dissection, aortic saccular aneurysms and even spontaneous aortic rupture. There are conflicting reports about the most common course of penetrating atherosclerotic ulcers 1.

Location

There is a greater predilection to involve the mid to distal thoracic aorta.

Radiographic features

CT

On CT aortography, the typical finding is a contrast-filled, out-pouching of the wall of the aorta or into the thickened aortic wall in absence of an intimal flap or a false lumen. The protrusion is said to resemble a mushroom 14. These can progress to an intramural hematoma. Often there are signs of extensive atherosclerosis in other sites apart from the ulceration 4.

Usually, the ulcer is found in the descending part of the thoracic aorta. Ulcers of the aortic arch are less common, and rare in the ascending aorta 4.

Although associated pleural effusion correlates with clinical instability there are no validated imaging features for prediction of the course of a PAU 1. It is often difficult to determine if a PAU is the source of a patient’s pain or if it is an incidental finding.

In follow-up studies increasing maximum diameter and depth of the ulcer is an obvious sign of progression 1. However, there is currently no consensus for ulcer depth or diameter that warrants treatment 14.

Transesophageal echocardiography

  1. usually, transesophageal echocardiography demonstrates a localized, crater-like protrusion of the aortic lumen into the thickened aortic wall.
  2. often there are signs of extensive atherosclerosis in other sites apart from the ulceration.

MRI and MRA

  1. T1-weighted SE sequences show a hyperintense hematoma in acute or subacute disease and can distinguish between hematoma and atherosclerotic plaque.
  2. otherwise, similar findings to CTA.

DSA

  1. the typical finding is a contrast-filled, pouch-like protrusion of the aortic lumen.
  2. mostly several oblique projections are required.

Treatment and Prognosis

No set guidelines on when to treat and practices vary between hospitals, however the general consensus is as follows:

  1. ascending aorta
    • although the involvement of the ascending aorta in penetrating atherosclerotic ulcers is rare, the ulcers usually rupture
    • therefore, early/urgent or emergent surgical intervention is recommended
  2. descending aorta
    • asymptomatic:
      • may initially be managed with an aggressive (antihypertensive) medical therapy in combination with close clinical and radiographic follow-up.
      • annual CT imaging follow-up has been suggested.
    • symptomatic or signs of progression:
      • higher risk for spinal cord ischemia
      • endovascular stent-grafting (TEVAR)
  3. iliac arteries
    • generally asymptomatic/incidental and slow-growing
    • mortality is determined by concurrent co-morbidities such as concurrent aortic aneurysm

3.2.5. Complications

Recognized complications include:

  1. transmural aortic rupture
  2. embolic phenomena
  3. pseudoaneurysm formation
  4. progressive aneurysmal dilatation

References

  1. Lansman S.L., Saunders P.C., Malekan R, et al. Acute aortic syndrome. J Thorac Cardiovasc Surg. 2010;140(6):S92-97.
  2. Cho KR, Stanson AW, Potter DD, et al. Penetrating atherosclerotic ulcer of the descending thoracic aorta and arch. J Thorac Cardiovasc Surg. 2004;127(5):1393-1399.
  3. Hayashi H, Matsuoka Y, Sakamoto I, et al. Penetrating atherosclerotic ulcer of the aorta: imaging features and disease concept. Radiograph 2000;20(4):995–1005.
  4. Baikoussis NG, Apostolakis EE. Penetrating atherosclerotic ulcer of the thoracic aorta: diagnosis and treatment. Hellenic J Cardiol. 2010;51(2):153-157.
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