**8. Prognosis**

*Differential Diagnosis of Chest Pain*

to repair the descending aorta.

*7.1.2 Type B aortic dissection*

repair is difficult.

**7.2 Long-term management**

ECHO (TTE) to look for aortic aneurysm.

long-term surveillance with imaging.

acute renal failure, and patients who were treated surgically.

ing to thrombosis causing closure of false lumen.

myocardial infarction, prior stroke, ischemia involving kidney or other viscera, advance renal or lung disease, and previous aortic valve replacement [25–31]. Open surgical repair for type A patients involves resection of the dissecting aneurysm and removal of intimal tear, closure of false lumen and repair of aorta using synthetic graft, and aortic valve repair/replacement. Repair of the aortic arch

Patients with genetic disease like Marfan causing Aortic regurgitation, bicuspid

An alternative to open surgical repair in type A patients with ischemic complications like renal, mesenteric, and peripheral ischemia is endovascular stent grafting. A novel approach involves the hybrid repair of type A dissection with "frozen elephant trunk repair technique," which involves open surgical repair of the ascending aorta in the form of a traditional elephant trunk and endoscopic stent grafting

Studies have compared the total arch replacement using the frozen elephant trunk repair technique (FET) with the hemi-arch replacement (AHR) for the type A ascending aortic dissection in which the survival for the patients after 5 years was 95.3% for the FET group and 69.0% for the AHR group, indicating that FET techniques prevent further operations for the complications because of the false lumen [25, 33–35].

Medical management is preferred for uncomplicated cases of type B aortic dissections unless the dissection or aneurysm expands, ischemic complications or aortic rupture occurs, or the patient has persistent uncontrolled hypertension or chest pain, when surgical treatment or endovascular grafting is to be considered. Conservative treatment for type B patients involves optimal BP control and

In the IRAD study of 384 patients with type B aortic dissection [36], 73 percent of patients were treated medically with mortality rate of 13% within the first week of admission. Factors associated with increased mortality were shock on presentation, widened mediastinum, excessively dilated aorta (≥6 cm), periaortic hematoma, patients with coma or altered consciousness, mesenteric or limb ischemia,

Endovascular stent grafting is done with the stent covering the dissection lead-

Open surgical repair is rarely done in type B patients. It may be needed in those patients with genetic condition like Marfan's syndrome in whom endovascular

Several trials have compared medical management with endovascular stent grafting in uncomplicated patients with type B aortic dissection demonstrating that at 2 years there is no difference in survival in either of the endovascular versus medical groups (89% versus 96%) [37]; however at 5 years the occurrence of the aortic complications is reduced in the endovascular group improving late outcome [38].

Optimal blood pressure control is needed to prevent recurrence or aneurysm formation. This is best achieved by oral combination antihypertensive therapy often including oral beta-blockers. Target blood pressure of less than 120/80 mmHg

Screening of first-degree relatives should be performed with transthoracic

may also be needed depending on the extent of the pathology.

aortic valve or aortitis need aortic valve replacement [32].

**74**

is preferred.

#### **8.1 Type a aortic dissection patients**

Untreated patients with type A dissections have a mortality rate of 1–2% per hour because of its association with high risk of complications of aortic rupture, tamponade, aortic regurgitation, ischemic complications of myocardial infarction, and stroke [24].

According to the IRAD follow-up study of 303 patients with type A dissection who were discharged from the hospital, surgically treated patients were 273 (90.1%), and medically treated patients were 30 (9.9%). Surgically treated patients had a 1-year survival of 96.1 ± 2.4% and 3-year survival of 90.5 + 3.9%, whereas the medically treated type A dissection patients had a 1-year survival of 88.6 + 12.2% and 3-year survival of 68.7 + 19.8% [39].

#### **8.2 Type B aortic dissection**

Uncomplicated type B patients have an overall survival rate of 90% with immediate medical management with effective control of blood pressure [36].

However in type B patients with complications of aortic rupture, expansion of dissection or ischemic complications of organ hypoperfusion the mortality rates were high. According to the IRAD study, the overall inhospital mortality rate was 13% during the first week, for all type B aortic dissection patients. Mortality rate in type B dissection patients with complications, undergoing surgical management, was 32.1%, whereas in those treated with medical management alone, the mortality rate was 9.6% and was 6.5% for those treated with endovascular approach [36].

The 3-year survival rate for type B patients who were discharged from the hospital according to the IRAD registry was 77.6 ± 6.6% for medically treated patients, 82.8 ± 18.9% for surgically treated patients, and 76.2 ± 25.2% for those treated with endovascular approach [40].
