Natural history of 40-50 mm root/ascending aortic aneurysms in the current era of dedicated thoracic aortic clinics.
OBJECTIVE
The natural history of root/ascending aortic aneurysms is based on studies from the 1980s to 1990s. Imaging and follow-up guidelines are based on these studies. Dedicated thoracic aortic clinics (TAC) ensure strict patient/imaging follow-up and tight blood pressure (BP) control. The aim of this study was to evaluate the natural history of medically treated root/ascending aortic aneurysms in the current era of dedicated TAC.


METHODS
Two hundred and fifty-one patients with 40-50 mm root/ascending aneurysms (all other aortic segments of <40 mm) were identified through a prospective collected databank. Patients were followed in a dedicated TAC. Serial (12-18 months interval) thoraco-abdominal computed tomographies (CTs), tight BP control (24 h arterial blood pressure monitoring) and isometric and exercise BP monitoring were performed.


RESULTS
The mean age was 65.4 ± 10.9 years; 29.5% of patients were female. Fifty-nine percent of patients had high BP. Aneurysm aetiology was atherosclerotic in 48.2% of patients, annulo-ectasia in 25.1% of patients, bicuspid valve-related in 21.5% of patients and another aetiology in 5.2% of patients. The initial aneurysm diameter was 46 ± 2.6 mm; 74.1% being between 46 and 50 mm. The mean follow-up (FU) was 4.3 ± 2.5 years, with a mean of 2.8 ± 1.1 CTs/pt. During FU, the increase in aortic size/year was 0.42 ± 0.82 mm/year for the root/ascending aorta (40-45 mm: 0.55 ± 0.77 mm/year vs 46-50 mm: 0.38 ± 0.84 mm/year; P = 0.14), 0.66 ± 1.11 mm/year for the arch, 0.45 ± 1.06 mm/year for the mid-descending aorta, 0.43 ± 1.0 mm/year for the aortic hiatus, 0.39 ± 0.87 mm/year for the suprarenal aorta and 0.41 ± 1.03 mm/year for the infrarenal aorta. Thirty patients (12%) were operated during FU. Surgical indication was disease progression on the aortic valve in 8 patients, root/ascending aorta progression of >50 mm in 14 patients and a root/ascending aorta replacement during FU without progression in 8 patients. One patient was operated emergently for an intramural haematoma after 3 years of follow-up. No patient required operation distal to the aortic arch. Operative mortality was 0/30 (0%). Thirty percent of patients required a concomitant hemiarch replacement. Four patients died during FU, with all deaths resulting from non-aortic causes. Freedom from acute aortic-related event and survival at 5 years were respectively 99.4 and 97.6%.


CONCLUSIONS
The present study suggests that the growth rate of 40-50 mm root/ascending aneurysms followed in a dedicated TAC aorta is lower than that shown in previously reported series. Freedom from aortic-related events and survival are high, thus necessitating long-term follow-up. These results challenge the current guidelines in terms of interval between imaging examinations and the extent and type of aortic imaging.
Department of Cardiovascular Surgery, Quebec Heart and Lung Institute, Laval University, Sainte-Foy, Canada.
Maude
M
Gagné-Loranger
Department of Cardiovascular Surgery, Quebec Heart and Lung Institute, Laval University, Sainte-Foy, Canada.
Éric
É
Dumont
Department of Cardiovascular Surgery, Quebec Heart and Lung Institute, Laval University, Sainte-Foy, Canada.
Pierre
P
Voisine
Department of Cardiovascular Surgery, Quebec Heart and Lung Institute, Laval University, Sainte-Foy, Canada.
Siamak
S
Mohammadi
Department of Cardiovascular Surgery, Quebec Heart and Lung Institute, Laval University, Sainte-Foy, Canada francois.dagenais@chg.ulaval.ca.
François
F
Dagenais
D000368:Aged; D000784:Aortic Dissection / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D001794:Blood Pressure / Q000502:physiology; D018660:Blood Pressure Monitoring, Ambulatory; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D019983:Guideline Adherence; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014656:Vascular Surgical Procedures / Q000379:methods*
Imaging surveillance; Natural history; Thoracic aneurysm