Evaluating current acute aortic syndrome pathways: Collaborative Acute Aortic Syndrome Project (CAASP)

Abstract

Background: Diagnosis of acute aortic syndrome is challenging and associated with high perihospital mortality rates. The study aim was to evaluate current pathways and understand the chronology of acute aortic syndrome patient care.

Method: Consecutive patients with acute aortic syndrome imaging diagnosis between 1 January 2018 and 1 June 2021 were identified using a predetermined search strategy and followed up for 6 months through retrospective case note review. The UK National Interventional Radiology Trainee Research and Vascular and Endovascular Research Network co-ordinated the study.

Results: From 15 UK sites, 620 patients were enrolled. The median age was 67 (range 25-98) years, 62.0% were male and 92.9% Caucasian. Type-A dissection (41.8%) was most common, followed by type-B (34.5%); 41.2% had complicated acute aortic syndrome. Mode of presentation included emergency ambulance (80.2%), self-presentation (16.2%), and primary care referral (3.6%). Time (median (i.q.r.)) to hospital presentation was 3.1 (1.8-8.6) h and decreased by sudden onset chest pain but increased with migratory pain or hypertension. Time from hospital presentation to imaging diagnosis was 3.2 (1.3-6.5) h and increased by family history of aortic disease and decreased by concurrent ischaemic limb. Time from diagnosis to treatment was 2 (1.0-4.3) h with interhospital transfer causing delay. Management included conservative (60.2%), open surgery (32.2%), endovascular (4.8%), hybrid (1.4%) and palliative (1.4%). Factors associated with a higher mortality rate at 30 days and 6 months were acute aortic syndrome type, complicated disease, no critical care admission and age more than 70 years (P < 0.05).

Conclusions: This study presents a longitudinal data set linking time-based delays to diagnosis and treatment with clinical outcomes. It can be used to prioritize research strategies to streamline patient care.

Fig. 1

Histograms demonstrating the distribution for times from symptom onset to hospital presentation a, admission to imaging diagnosis b and diagnosis to treatment c Smoothed data is plotted in black. Above individual histograms are box and whisker plots with a red line for median, ‘+’ for the mean, a blue box around the 25 and 75% quartiles and whiskers bounding 9 and 91%.

Fig. 2

Distribution of timepoints over the 15 UK centres Mean time points for each centre are shown as horizontal lines and are placed over a 1.96× standard error of the mean (95% confidence interval) in a time from symptom onset to hospital presentation, b time from admission to imaging diagnosis and c time from diagnosis to treatment, expressed in hours.

Fig. 3

Distance from hospital and time from onset to hospital presentation stratified by index of deprivation a (low 1–5) and b high (6–10)

Fig. 4

Kaplan–Meier survival curves: (a) overall; and for each of the independent predictors of mortality rate including: (b) aortic pathology, (c) presence of complicated disease, (d) admission to critical care and (e) age less than 70 years IMH, intramural haematoma.

Fig. 4

Kaplan–Meier survival curves: (a) overall; and for each of the independent predictors of mortality rate including: (b) aortic pathology, (c) presence of complicated disease, (d) admission to critical care and (e) age less than 70 years IMH, intramural haematoma.

Fig. 4

Kaplan–Meier survival curves: (a) overall; and for each of the independent predictors of mortality rate including: (b) aortic pathology, (c) presence of complicated disease, (d) admission to critical care and (e) age less than 70 years IMH, intramural haematoma.