Freestyle Prosthesis for Aortic Root-replacement With and Without Hemiarch Replacement

Freestyle Prosthesis for Aortic Root-replacement With and Without Hemiarch Replacement in Various Pathologies: A Retrospective Analysis

The Freestyle® prosthesis (Medtronic plc, Dublin, Ireland) is a biological, porcine aortic root implanted in various combinations and techniques since the 1990s. The main indication for the choice of this prosthesis is a combined pathology with degenerated aortic valve and additional dilatation of the root often involving the ascending aorta.

The Freestyle® prosthesis is also used in cases of dissection of the ascending aorta with the involvement of the aortic valve, which opens the debate on how far the ascending aorta should be replaced for a sustainable solution with calculable low periprocedural risk. Considering a lower intraoperative risk in the life-threatening situation, an extended resection of the aorta can be avoided and only the aortic root replaced with a piece of ascending aorta. On the contrary, focusing on improved long-term outcome, the technique of total arch replacement in aortic dissection was developed in emergency situations with acceptable results, which, however, were often reproducible only in large, experienced centers.

Apart from the abovementioned options, the technique of proximal arch replacement can provide a tension-free anastomosis. The intention of hemiarch replacement is the attachment of the prosthesis to an aneurysm-free portion of the aortic arch helping to protect against further anastomotic aneurysms and spare the patient complex reoperation or interventional procedures in the future. As a possible drawback of the technique, especially in emergency situations, the potentially prolonged duration of surgery and the need of selective brain perfusion via axillary or carotid artery are discussed increasing the risk of stroke and further major events, which could not be reflected in current literature. However, there is still no convincing evidence of a long-term benefit in terms of re-operation and survival after hemiarch replacement.

The aim of this retrospective analysis was to assess the mid-term outcome of the biological Freestyle® prosthesis in combination with operations on the ascending aorta and the aortic arch with regard to prosthetic performance, reoperations, stroke and death.

Study Overview

• Status: Completed
• Conditions: Endocarditis; Aortic Aneurysm; Aortic Dissection; Valve Heart Disease; Root Abscess
• Intervention / Treatment: Procedure: Aortic root replacement with Freestyle biological prosthesis with and without hemiarch replacement

• Study Type: Observational
• Enrollment (Actual): 278

Contacts and Locations

Study Locations

• Switzerland
  • Zürich, Switzerland, 8063
    • Triemli Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

From September 2007 till March 2017, we performed 278 aortic root replacements with the Freestyle prosthesis at a single centre in Switzerland. Two groups were identified based on the additional replacement of the hemiarch resulting in 119 patients (HA) and 159 patients without an additional hemiarch replacement (non-HA). Patients with additional valve and coronary artery procedures were included as well. Out of the non-HA group, 7 patients were cannulated through the femoral artery and excluded for further analysis.

Description

Inclusion Criteria:

• all patients after implantation of a biological Medtronic Freestyle root prosthesis in the time frame from November 2007 till April 2017
• elective, urgent and emergency operations on ascending aneurysms, aortic dissections, endocarditis and aortic root pathologies
• combination of other procedures (coronary artery bypass grafting, operations on mitral and tricuspid valve, ablations)

Exclusion Criteria:

• refused patient consent

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Hemiarch; Patients with Freestyle aortic root implantation receiving a hemiarch replacement by open anastomosis technique with axillary cannulation and antegrade cerebral perfusion	Procedure: Aortic root replacement with Freestyle biological prosthesis with and without hemiarch replacement; Aortic root replacement with Freestyle biological prosthesis. Some patients receive additional hemiarch replacement performing an open anastomosis to the aortic arch under antegrade cerebral perfusion through axillary artery. Comparison with patients, who were cannulated and perfused systemically
Non-Hemiarch; Patients with Freestyle aortic root implantation without hemiarch replacement with normal systemic perfusion	Procedure: Aortic root replacement with Freestyle biological prosthesis with and without hemiarch replacement; Aortic root replacement with Freestyle biological prosthesis. Some patients receive additional hemiarch replacement performing an open anastomosis to the aortic arch under antegrade cerebral perfusion through axillary artery. Comparison with patients, who were cannulated and perfused systemically

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
In-hospital mortality	In-hospital mortality	30 days after initial operation
Major and minor in-hospital complications	stroke, myocardial infarction, re-operation, pacemaker implantation	30 days after initial operation
Valve performance	Mean valve gradient of the implanted root prosthesis	earliest to longest follow up (longest follow up period of 10 years)

Collaborators and Investigators

• Sponsor: Triemli Hospital
• Investigators: Principal Investigator: Alicja Zientara, MD, Triemli Hospital

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2018
• Primary Completion (Actual): March 1, 2019
• Study Completion (Actual): August 1, 2019

Study Registration Dates

• First Submitted: August 21, 2019
• First Submitted That Met QC Criteria: August 23, 2019
• First Posted (Actual): August 28, 2019

Study Record Updates

• Last Update Posted (Actual): August 28, 2019
• Last Update Submitted That Met QC Criteria: August 23, 2019
• Last Verified: August 1, 2019

More Information

Terms related to this study

• Keywords: cardiopulmonary bypass; hemiarch replacement; cannulation technique; selective cerebral perfusion
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Aortic Diseases; Heart Diseases; Aneurysm; Aneurysm, Dissecting; Heart Valve Diseases; Endocarditis; Aortic Aneurysm
• Other Study ID Numbers: BASEC-Nr. 2018-01227

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No