Long-term outcomes following exclusive conservative medical treatment of uncomplicated type B aortic dissection: a nationwide 23-year follow-up
A Tanindi, S Thunstrom, C Basic, M Fu, M Lindgren, P Skoog, K Smidfelt, G Smith, A Rosengren, A D Sturedahl, E ThunstromAbstract
Background/Introduction
Aortic dissection is a life-threatening condition with an estimated annual incidence of 3 per 100,000. Type B aortic dissections originate distal to the left subclavian artery and are confined to the descending aorta. They are considered uncomplicated in the absence of aortic rupture, hemodynamic instability, rapid aortic expansion or organ malperfusion. Acute uncomplicated aortic dissections are traditionally managed medically, focusing on blood pressure and heart rate control.
Purpose
The primary aim of this study is to evaluate the long-term risk of aortic complications of conservatively managed patients with initially uncomplicated type B aortic dissection. The secondary aim is to compare aortic dissection-related mortality and all-cause mortality with matched controls from the general population.
Methods
This nationwide, register-based observational cohort study included all patients (n=5,248) in Sweden with an incident diagnosis of uncomplicated type B aortic dissection between 2000 and 2023, who were managed conservatively with medical therapy and survived the first three months after diagnosis. Patients were identified through the National Patient Registry and follow-up commenced three months after the index event, continuing until the end of 2023. Each patient was matched with five individuals from the general population based on age, sex, and geographic region, resulting in a control group comprising a total of 26,240 individuals.
Results
The median age of the cases and the controls was 70 years (19-99), and 62.4% were males. Patients with type B aortic dissection had significantly more frequent hypertension (72% vs 24%), hyperlipidemia (13% vs 6.6%), established cardiovascular disease (19.9% vs 8.9%) and previously known unruptured aortic aneurysm (25.7%vs 0.9%) (p: <0.01 for all). Aortic rupture occured in 215 of the cases comprising 4.1% of all cases. In total, 109 patients needed to undergo open or endovascular surgery (TEVAR/EVAR) during the follow-up which corresponded to 2.1% of the cases. Mortality rate associated with aortic dissection/rupture was 6.8 % (n= 355) in the cases vs 0.1%(n = 38) in the control group (adjusted HR: 49; 95% CI (35-69) , p: <0.0001). Unadjusted HR for all-cause mortality was 1.89; 95% CI (1.8-1,97), p: <0.0001 whereas adjusted HR according to age, sex and all co-morbidities was 1.66; 95 % CI (1.58-1.76) p: <0.0001).
Conclusion
Long-term all-cause mortality following initial medical management of uncomplicated type B aortic dissection remains significantly higher than in matched controls, yet the absolute risk of subsequent aortic events is low. These findings support the safety and effectiveness of current Swedish patient selection and follow-up strategies for conservative first-line management. The relatively low recurrence risk underscores the importance of reassuring patients that additional aortic events are less common than commonly perceived.For image description, please refer to the figure legend and surrounding text.figureFor image description, please refer to the figure legend and surrounding text.