When the vessels of vessel bleed: A case of aortic intramural hematoma involving descending thoracic and abdominal aorta

Karthik Raja, Vidya Saketharaman

Department of emergency medicine, Kauvery hospital Alwarpet Chennai

Abstract

Intramural hematoma (IMH) is a life-threatening aortic disease included within acute aortic syndrome, together with aortic dissection (AD) and penetrating aortic ulcer (PAU). IMH is a contained aortic wall hematoma with bleeding within the media but without initial intimal flap formation. Approximately 10–30% of patients with acute aortic syndrome have IMH. IMH converts to acute aortic dissection in 3–14% of patients with involvement of the descending aorta and in 88% of those with involvement of the ascending aorta, with high mortality rates.

Hence, we report a case of Aortic Intra Mural Hematoma in which timely diagnosis and management prevented acute aortic dissection.

Case report

A 52 years aged gentleman presented to the Emergency department at 7:45 pm with the complaints of severe lower back pain initially radiating to upper back and anterior abdomen which was persistent in nature since 3:30 am. Patient initially consulted a local clinic at which ECG showed hyper acute T waves in anterior leads. Troponin I was done and was negative. In view of persistent pain, he came here for further management. He was known to have hypertension with baseline BP 200/100 mmHg, and for 2 years not on regular medications. Patient was a chronic smoker, 15 pack years. There was no history of similar complaints in the past.

On clinical assessment

Conscious, Oriented, afebrile, hydration fair,

Pulse	BP	RR	SPO2	TEMP	CBG	GCS	PS
74/min	200/100mmhg	22/m	97%RA	98.6 F	211mg/dl	15/15	4/10

No pallor, icterus, cyanosis, clubbing, lymphadenopathy or edema

Airway- Patent, self-maintained

Breathing – B/L air entry present, and chest clear

Circulation-Four limb BP same. All peripheral pulses felt equally well. , no radio femoral delay

Per Abdomen: No abnormal abdominal pulsations, non-tender, BS+

Disability: GCS 15/15, B/L PERL CBG- 211

Exposure–afebrile, tall Marfanoid features

ECG

ECG (figure 1)	ECHO
NSR, Normal axis ST depression in lead II, aVF, V5, V6 Hyper acute T waves in V3, V4 No dynamic changes comparing	Concentric LVH , Thickened Aortic valve, RWMA–inferoposterior , anterior wall hypokinetic, mild LV dysfunction LVEF 40% ,Trivial AR, no AS, Trivial MR , Trivial TR

Lab investigations

Hb	13.6 gm/dl
Urea	14mg/dl
Creatinine	0.92 mg/dl
Sodium	141 mmol/L
Potasium	3.7 mmol/l
RBS	211 mg/dl
Troponin I	0.04(negative)
Total WBC	11,050 cells
D- Dimer	3877
NT-PRO BNP	181

To rule out (R/O) Aortic Dissection urgent CT Aortogram was done which was ssuggestive of Type B Acute Aortic Intramural Hematoma involving descending thoracic and abdominal aorta. Ascending aorta, proximal arch and descending thoracic aorta were dilated. Fusiform aneurysmal dilation of infra renal aorta upto bifurcation with another segment of intramural hematoma. No features suggestive of dissection.

The aortic measurements at various levels were as follows

Level dimensions of Aorta (mm)

Ascending aorta	34
Proximal Aortic arch	31
Mid Aortic arch	29
Distal Aortic arch	30
Descending Thoracic aorta	41 (IMH – 6)
Distal descending thoracic aorta	32 (IMH -4 )
Supra renal abdominal aorta	36
At the level of renal arteries	24
Infra renal abdominal aorta	36* 36 (IMH -10)
Right and left common iliac	15,13

Course in the hospital

Patient was admitted to CCU; aggressive BP control with target BP 120 /70 using multi drug strategy given.
Cardiothoracic Surgeon opinion: Advised aggressive BP control.
Vascular surgeon opinion: Advised to maintain blood pressure < 120/70 mmHg.
With continued antihypertensives, achieved target BP < 120/70 mmHg. Patient symptomatically improved and hence discharged with strict bp control medications and regular follow-ups.

Discussion

Intramural hematoma (IMH) is a life-threatening aortic disease included within acute aortic syndrome, together with aortic dissection (AD) and penetrating aortic ulcer (PAU).

Acute Aortic Syndrome Triad

Approximately 10–30% of patients with acute aortic syndrome have IMH. Similar to acute aortic dissection, it is classified as Stanford type A (ascending aorta) or B (exclusive involvement of the descending aorta). Most patients with IMH have Stanford type B (50–85%)

Common predisposing factors for Aortic Intramural Hematoma include:

Hypertension
Smoking
Hyperlipidaemia
Cocaine use
Connective tissue disorders, e.g., Marfan syndrome, Ehlers-Danlos syndrome, Turner syndrome
Hereditary valvular disease such as bicuspid aortic valve or coarctation of the aorta
Vascular inflammation – autoimmune – GCA, Infection – syphilis
Trauma – deceleration
Iatrogenic – catheter insertion, valvular or aortic surgery

Pathogenesis of Intramural Hematoma

Where does the blood come from for IMH?

Vasa Vasorum- they are small blood vessels supplying the large blood vessels such as aorta.
These small vessels serve to provide blood supply and nourishment to Tunica Adventitia and outer parts of Tunica Media of large vessels. IMH develops from damage/ injury to the vasovasorum .
Vaso vasorum translates to “the vessel of vessels” in Latin. First described by English physician Thomas Willisin 1678, it was initially termed “vasa arteriosa” by Dutch anatomist Frederik Ruysch in 1696. The term “vasa vasorum” was coined by the German physician Christian Ludwig in 1739, now adopted in contemporary literature as described in the pictures below (fig 1)

How is aortic IMH differ from aortic dissection?

In IMH there is no rupture of the tunica intima and no false lumen of the aorta.
In aortic dissection there is rupture of the tunica intima and false lumen present as described in the picture below (fig 2)

Fig (1): Rupture of Vaso Vasorum forming IMH

Fig (2): Acute Aortic Syndrome components

Complications of Intra Mural Hematoma

Fig (3): Complications of Intra Mural Hematoma

These patients have higher rates of periaortic hematoma, pericardial effusion, and rupture in the mediastinum. Cardiac tamponade, which occurs in 19% of patients with acute type A dissection, is one of the most common causes of death in patients with this disorder. Patients with IMH caused by PAU are also prone to complications of PAUs, including pseudoaneurysm formation, rupture into the pericardial sac (haemorrhagic pericardial effusion), haemorrhagic pleural effusion, and aortic dissection.
Recognition of acute coronary syndrome in IMH is important because primary coronary intervention and thrombolytic therapy was contraindicated in these patients.
ST-segment elevation myocardial infarction occurred in 3.3% of patients with IMH and was attributable to direct coronary involvement. The possible mechanisms of myocardial infarction in IMH, which may be like acute dissection, include type A, coronary compression; type B, retrograde dissection; type C, coronary artery detachment; in situ thrombosis.
This patient had ECG and ECHO findings of myocardial Ischemia. It is very important to keep in mind the possibility of dissection in patient presenting with severe back pain with high blood pressure.
Hence, advanced imaging like TTE/TEE, CT Aortogram, MRI helps differentiate in these conditions to take a better decision.
Our patient underwent CT Aortogram, which was suggestive of Type B Acute aortic intramural hematoma involving descending thoracic and abdominal aorta. Ascending aorta, proximal arch and descending thoracic aorta were dilated. Type B IMH is usually conservatively managed with anti-hypertensives with a target BP of <130/70 mm Hg.
According to a study by Tomaz mesar et al, IMH thickness was the sole predictive risk factor for medical therapy failure with a presenting IMH thickness of ≥8.0 mm and uncomplicated type B IMH (ref 1). Our IMH thickness was 4–6 mm hence ideal candidate for medical conservative therapy.

According to European society for vascular surgery

Take home points

It is important to rule out acute aortic syndrome in patients with high BP and back pain.
Acute Aortic Syndrome can present with dynamic ECG changes hence excessive caution to rule out AOS before planning anti platelet therapy
Patient with marfanoid habitus, high BP, smoker and back pain – rule out AOS.
Timely intervention in IMH with excellent BP control will prevent catastrophic complications.

Acknowledgement

I thank Dr. Aslesha Vijaay Sheth (Head of the Emergency medicine department) Kauvery Hospital Alwarpet, Chennai.

Dr. Booma (Associate Consultant) Department of Cardiology Kauvery Hospital Alwarpet for supporting me in writing this article.

Reference

Dr. Vidya Saketharaman
Consultant – Emergency Physician

When the vessels of vessel bleed: A case of aortic intramural hematoma involving descending thoracic and abdominal aorta

When the vessels of vessel bleed: A case of aortic intramural hematoma involving descending thoracic and abdominal aorta

Karthik Raja, Vidya Saketharaman

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