The NEOS post-market clinical follow-up study is undertaken to demonstrate the safety and clinical performance of E-vita OPEN NEO in the treatment of aneurysm or dissection in the ascending aorta, aortic arch and descending thoracic aorta.

In this study, patients will be observed who receive an E-vita OPEN NEO implant for the treatment of thoracic aneurysm or acute or chronic thoracic dissection. E-vita OPEN NEO will be implanted according to the instructions for use and at the discretion of the treating physician.

Participating physicians will provide their observations collected during routine care for patients treated with E-vita OPEN NEO. Written informed consent, specifically allowing the use of clinical records for this observational study, will be obtained from every patient prior to data collection.

The period of data collection will be approximately 60 months from the date of intervention for each patient. Source data verification will be performed on 100% of the patients; data from all the visits that was provided in the database will be reviewed and verified against existing source documents. Complete DICOM image files of the CT scans will be sent to the CoreLab for independent evaluation. All adverse events defined prior to study start will be adjudicated by the Clinical Event Committee (CEC).

Inclusion Criteria:

• Patient´s age is between 18 and 75 years.
• Patient is willing and able to comply with the standard follow-up visits planned after the implantation procedure.
• Patient is willing and able to give informed consent.
• Patient satisfies one of the following categories:
• Patient has acute / subacute aortic dissection and requires repair or replacement of damaged or diseased vessels of the aortic arch (with or without involvement of the ascending aorta), and the descending aorta requires treatment, or, in the opinion of the investigator, the patient would derive clinical benefit from prophylactic treatment of the descending aorta.
• Patient has chronic aortic dissection which requires repair or replacement of damaged or diseased vessels of the aortic arch and descending aorta with or without involvement of the ascending aorta, and the patient satisfies one or more of the following criteria:

Patient has aortic sinus, or ascending aorta, or aortic arch, or descending aorta diameter ≥ 5.5 cm.

Patient has aorta diameter < 5.5 cm and a growth rate of ≥ 0.5 cm / year. Patient has ascending aorta diameter ≥ 4.5 cm and requires an aortic valve repair or replacement.

Patient has clinical signs of abdominal or peripheral malperfusion.

• Patient has a fusiform or saccular aortic aneurysm which requires repair or replacement of damaged or diseased vessels of the aortic arch and descending aorta with or without involvement of the ascending aorta, and patient satisfies the following criteria:

Patient has a suitable distal sealing area in the descending thoracic aorta proximal to the celiac trunk.

And in case of fusiform aneurysm one of the following characteristics:

Patient has aortic sinus, or ascending aorta, or aortic arch, or descending aorta diameter ≥ 5.5 cm.

Patient has aorta diameter < 5.5 cm and a growth rate of ≥ 0.5 cm / year. Patient has ascending aorta diameter ≥ 4.5 cm and requires an aortic valve repair or replacement.

• Patient is hemodynamically stable without pharmacological support at time of admission to the hospital (stable blood pressure and heart rate, no shock).

Exclusion Criteria:

• Patient is unfit for open surgical repair involving circulatory arrest.
• Patient has known sensitivities or allergies to nitinol, polyester, platinum-iridium, or polyethylene.
• Patient has systemic infection.
• Patient has endocarditis or active infection of the aorta.
• Patient has a free ruptured aorta.
• Patient has acute stroke or suspected acute stroke.
• Patient is on inotropes at time of arrival to the hospital.
• Patient needs mitral valve repair or replacement.
• Patient is enrolled or plans to be enrolled in another active study.
• Patient is pregnant or breastfeeding or planning to become pregnant during the course of the study.
• Patient has uncorrectable bleeding anomaly (i.e., thrombocytopenia).
• Patient has an eGFR < 45 ml/min/1.73m2 before the intervention
• Patient has known sensitivity to radiopaque contrast agents that cannot be adequately pre-treated.
• Patient has co-morbidity (i.e. active malignancy (progressive, stable or partial remission)) causing expected survival to be less than 3 years.
• Patient has any other medical, social or psychological problems, that in the opinion of the investigator, preclude the patient from participating in this study.

Male and female patients with thoracic aortic dissection or aneurysm who are eligible for surgical treatment with the frozen elephant trunk technique according to the instructions for use for E-vita OPEN NEO and scheduled for implantation of E-vita OPEN NEO at their physician's discretion in accordance with the inclusion and exclusion criteria.