Clinical and radiological features of thoracic aortic disease

Abstract

Background:

The pathologies of the aorta constitute a group of severe diseases often managed by means of a single variable, the maximum aortic diameter. This variable is insufficient, and the aim of this work is to help prevent severe aortic events, to help develop surgical decisions and improve the results of surgery.

Methods and Results:

Study I - Survival and events in patients with moderately dilated proximal thoracic aorta. All patients referred to the Thoracic Aortic outpatient clinic at Karolinska University Hospital between 1992-2011, with a baseline proximal aortic diameter of 4.5-5.4 cm without other established primary indication for surgery and subject to CT follow-up (n=80) were included. Data on aortic growth, all-cause mortality, aortic mortality, aortic events and relative survival were obtained from medical records and questionnaires, CT imaging, The National Cause of Death Register and the Human Mortality Database, respectively. Overall, 35% of patients experienced an event. Relative survival compared to a matched normal population was 82% (95% CI 55- 98%) at 10 years. Increasing diameter of the descending aorta was an independent predictor of all-cause death (HR 1.39) and aortic death (HR 1.96).

Study II - Growth, survival and events in patients with aortic arch pathology. All patients referred to the Thoracic Aortic outpatient clinic at Karolinska University Hospital between 1992-2011, that had an index diameter ≥4.5 cm or other pathology in the native aortic arch and were subjects to CT follow-up (n=186) were included. Data on aortic growth, all-cause mortality, aortic mortality and aortic events were obtained from patient charts and questionnaires, CT imaging and the National Cause of Death Register, respectively. Twenty-five percent of patients had an event of any kind and 32% percent of events, both local and remote, were an acute aortic syndrome, preceded by growth in the aortic arch. Five years estimated freedom from all events was 66% (95% CI 56-79%)and an increasing descending aortic diameter was an independent predictor of all cause death (HR 2.16), aortic death (HR 4.81) and local event in the aortic arch (HR 1.71).

Study III - Association between inguinal hernia and thoracic aortic dilatation. Men with prior inguinal hernia repair and as controls men with a prior cholecystectomy performed in the Department of Surgery at Ersta Hospital between 2016 and 2019 (n=470), were included. Data on thoracic aortic diameters and thoracic aortic dilatation (>45 mm root or ascending diameter; >35 mm isthmic or descending diameter) were obtained from patient questionnaires, CT imaging and the National Cause of Death register. Thoracic aortic dilatation prevalence was in the inguinal hernia group significantly higher vs. controls: 9.7% vs. 2.4%, p=0.001 for proximal aorta, 13% vs. 8.3%, p=0.049 for distal aorta, and 23% vs. 11%, p<0.001 for all aortic segments combined. An independent association between inguinal hernia and dilatation of the proximal aorta was found (OR 5.3).

Study IV - Outcomes in patients with proximal aortic repair. All nonsyndromic, asymptomatic patients who underwent elective, first-time, prophylactic proximal aortic surgery in the Department of Cardiothoracic Surgery, Karolinska University Hospital, between 2014 and 2019 (n=262) were included. Data on all-cause mortality and major complications were obtained from patient charts and the Swedish Population Register. Overall, mortality was 0.76% and remained unchanged at 1-year postoperative follow-up. The presence of major complications was in the 0-1.5% range. Freedom from aortic death was estimated to 97% (95% CI 91-99%) at 5 years postoperatively.

Conclusions:

More aortic related deaths with worse overall survival, more remote events and with an increasing descending aortic diameter as an independent predictor of all-cause death and aortic death were noticed.

Continuing growth in the aortic arch prior to the occurrence of an event can be expected as well as events in terms of deaths and acute aortic syndromes. An increasing descending aortic diameter served as an independent predictor of all-cause death, aortic death and local event.

In men with inguinal hernia, higher prevalence of aortic dilatation than in controls, was demonstrated.

The outcomes of asymptomatic, nonsyndromic patients undergoing elective, firsttime proximal aortic surgery were excellent.