Dataset Information

Evaluating Growth Patterns of Abdominal Aortic Aneurysm Diameter With Serial Computed Tomography Surveillance.

ABSTRACT:

Importance

Small abdominal aortic aneurysms (AAAs) are common in the elderly population. Their growth rates and patterns, which drive clinical surveillance, are widely disputed.

Objective

To assess the growth patterns and rates of AAAs as documented on serial computed tomography (CT) scans.

Design, setting, and participants

Cohort study and secondary analysis of the Non-Invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA3CT), a randomized, double-blind placebo-controlled clinical trial conducted from 2013 to 2018, with CT imaging every 6 months for 2 years. The trial was a multicenter, observational secondary analysis, not related to treatment hypotheses of data collected in the N-TA3CT. Participants included 254 patients with baseline AAA diameter between 3.5 and 5.0 cm.

Exposures

Patients received serial CT scan measurements, analyzed for maximum transverse diameter, at 6-month intervals.

Main outcomes and measures

The primary study outcome was AAA annual growth rate. Secondary analyses included characterizing AAA growth patterns, assessing likelihood of AAA diameter to exceed sex-specific intervention thresholds over 2 years.

Results

A total of 254 patients, 35 women with baseline AAA diameter 3.5 to 4.5 cm and 219 men with baseline diameter 3.5 to 5.0 cm, were included. Yearly growth rates of AAA diameters were a median of 0.17 cm/y (interquartile range [IQR], 0.16) and a mean (SD), 0.19 (0.14) cm/y. Ten percent of AAAs displayed minimal to no growth (<0.05 cm/y), 62% displayed low growth (0.05-0.25 cm/y), and 28% displayed high growth (>0.25 cm/y). Baseline AAA diameter accounted for 5.4% of variance of growth rate (P < .001; R2, 0.054). Most AAAs displayed linear growth (70%); large variations in interval growth rates occurred infrequently (3% staccato growth and 4% exponential growth); and some patients' growth patterns were not clearly classifiable (23% indeterminate). No patients with a maximum transverse diameter less than 4.25 cm exceeded sex-specific repair thresholds at 2 years (men, 0 of 92; 95% CI, 0.00-0.055; women, 0 of 25 ; 95% CI, 0.00-0.247). Twenty-six percent of patients with a maximum transverse diameter of at least 4.25 cm exceeded sex-specific repair thresholds at 2 years (n = 12 of 83 men with diameter ranging from 4.25 to <4.75 cm; 95% CI, 0.091-0.264; n = 21 of 44 men with diameter ranging from 4.75-5.0 cm; 95% CI, 0.362-0.669; n = 3 of 10 women with diameter ≥4.25 cm; 95% CI, 0.093-0.726).

Conclusions and relevance

Most small AAAs showed linear growth; large intrapatient variations in interval growth rates were infrequently observed over 2 years. Linear growth modeling of AAAs in individual patients suggests smaller AAAs (<4.25 cm) can be followed up with a CT scan in at least 2 years with little chance of exceeding interventional thresholds.

Trial registration

ClinicalTrials.gov Identifier: NCT01756833.

SUBMITTER: Olson SL

PROVIDER: S-EPMC7890454 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Publications

Evaluating Growth Patterns of Abdominal Aortic Aneurysm Diameter With Serial Computed Tomography Surveillance.

Olson Sydney L SL Wijesinha Marniker A MA Panthofer Annalise M AM Blackwelder William C WC Upchurch Gilbert R GR Terrin Michael L ML Curci John A JA Baxter B Timothy BT Matsumura Jon S JS

JAMA surgery 20210401 4

<h4>Importance</h4>Small abdominal aortic aneurysms (AAAs) are common in the elderly population. Their growth rates and patterns, which drive clinical surveillance, are widely disputed.<h4>Objective</h4>To assess the growth patterns and rates of AAAs as documented on serial computed tomography (CT) scans.<h4>Design, setting, and participants</h4>Cohort study and secondary analysis of the Non-Invasive Treatment of Abdominal Aortic Aneurysm Clinical Trial (N-TA3CT), a randomized, double-blind plac ...[more]

PMID: 33595625

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Dataset Information

Evaluating Growth Patterns of Abdominal Aortic Aneurysm Diameter With Serial Computed Tomography Surveillance.

Importance

Objective

Design, setting, and participants

Exposures

Main outcomes and measures

Results

Conclusions and relevance

Trial registration

Publications

Evaluating Growth Patterns of Abdominal Aortic Aneurysm Diameter With Serial Computed Tomography Surveillance.

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