**3. Risk factors**

Men form approximately 62–68% of all patients undergoing surgery [7]. The triad of hypertension (67–86% patients), smoking and atherosclerosis is an independent predictor of type A aortic dissection [8]. Data correlating the risk of aortic dissection in bicuspid aortic valve is limited and controversial. However, some centres advocate early prophylactic ascending aortic replacement in patients with aortas larger than approximately 5.0 cm in diameter or with a cross-sectional area to height ratio greater than approximately 10 cm2 /m [9]. In the NORCAAD registry, 6% patients were reported to have bicuspid aortic valve [7]. The Marfan syndrome is present in around 4% of ATAAD patients in NORCAAD registry [10]. The patients typically have pearshaped aneurysm of aortic root. Due to mutation in FBN1 gene, there is decreased strength and elasticity of elastin—rich tissue of aortic wall. Predominantly, medium and large sized arteries are involved in dissection (**Table 1**).

**63**

**5. Diagnosis**

are good indicators for TAAD [13].

non-specific [14].

*Current and Future Management Strategies of Type A Aortic Dissection*

*DOI: http://dx.doi.org/10.5772/intechopen.93015*

(1) Cardiovascular and life style factors Uncontrolled hypertension

(2) Congenital and connective tissue

Bicuspid aortic valve Marfan syndrome

Coronary catheterisation Arterial cannulation Aortic cross clamping

(4) Vascular inflammation Takayasu arteritis

Deceleration injury

(3) Iatrogenic

IABP

(5) Trauma

**Table 1.**

Age Smoking Dyslipidemia Cocaine Pregnancy

**4. Clinical presentation**

*Risk factors for acute aortic dissection.*

TAAD patients (85%) typically present with sudden intense central chest pain (ripping or tearing) radiating to the neck, back or abdomen. [11]. ECG abnormalities (50% patients) include ST/T wave changes, conduction defects, and arrhythmias. This sometimes leads to the misdiagnosis of myocardial infarction leading to fatal mistake of giving antiplatelet therapy or thrombolysis. This delays the diagnosis and increases peri-operative bleeding complications. Aortic regurgitation (70% patients) can occur through prolapse of right or non- coronary valve cusps and detachment of commissures. Pulmonary oedema may occur through acute dilation of the left ventricle. Haemorrhagic pericardial tamponade is a very strong predictor of aortic dissection. Reduced or absent femoral pulses are seen. Neurological sequlae include syncope, stroke. Mal-perfusion of spinal cord leads to paraplegia. Acute renal failure and mesenteric ischemia are seen if the dissection involves descending thoracic and abdominal aorta [12]. Rupture of the aneurysm is immediately fatal.

1.**Clinical**: Constellation of findings of chest pain, diastolic murmur, blood pressure difference in both upper limbs, pulse deficit, neurological sequelae

2.**Chest X ray** (**Figure 2**) shows widened mediastinum (49% patients), which is


### **Table 1.**

*Advances in Complex Valvular Disease*

to guide acute management. Stanford type A involves ascending aorta proximal to innominate artery, irrespective of involvement of aortic arch or descending aorta. Stanford type B dissection involves only the thoracic aorta distal to the left subclavian artery [5]. Intimal tears originating distal to left subclavian artery but dissecting retrogradely into ascending aorta will be type A. Intimal tears starting in the aortic arch and extending into ascending aorta are type A and extending into descending aorta are type B. If the intimal tear is restricted to aortic arch, then it is

The DeBakey type I involves ascending aorta and extends beyond the innominate artery. Type II involves only the ascending aorta. Type III involves thoracic aorta distal to left subclavian artery. It is more useful for long-term follow-up as it differentiates between proximal and distal aortic dissection extent (**Figure 1**) [4]. The Penn classification is a recently introduced method of classifying based on clinical presentation [6]. Class Aa—absence of branch vessel malperfusion or circulatory collapse; Class Ab—symptoms or signs of localised organ ischemia; Class Ac—circulatory collapse with or without cardiac involvement; Class Abc—

Men form approximately 62–68% of all patients undergoing surgery [7]. The triad of hypertension (67–86% patients), smoking and atherosclerosis is an independent predictor of type A aortic dissection [8]. Data correlating the risk of aortic dissection in bicuspid aortic valve is limited and controversial. However, some centres advocate early prophylactic ascending aortic replacement in patients with aortas larger than approximately 5.0 cm in diameter or with a cross-sectional area to height ratio greater

reported to have bicuspid aortic valve [7]. The Marfan syndrome is present in around 4% of ATAAD patients in NORCAAD registry [10]. The patients typically have pearshaped aneurysm of aortic root. Due to mutation in FBN1 gene, there is decreased strength and elasticity of elastin—rich tissue of aortic wall. Predominantly, medium

and large sized arteries are involved in dissection (**Table 1**).

/m [9]. In the NORCAAD registry, 6% patients were

**62**

type non-A non-B.

*Stanford and DeBakey classification.*

**Figure 1.**

**3. Risk factors**

than approximately 10 cm2

combined localised and generalised ischemia.

*Risk factors for acute aortic dissection.*
