Comparison of dynamic changes in aortic diameter during the cardiac cycle measured by computed tomography angiography
Jian Huang1, Yongsheng Wang2, Lin Lin3
1Department of Cardiovascular Surgery, Nanfang Hospital, Southern Medical University/The First School of Clinical Medicine, Southern Medical University, Guangzhou, China; Department of Cardiovascular Surgery, The First Affiliated Hospital of Xiamen University, Xiamen, China.
Insights
This study found that measurements of the ascending aorta using intraoperative ultrasound (IOUS), computed tomography angiography (CTA), and transthoracic echocardiography (TTE) show good agreement. These imaging methods accurately capture dynamic changes in aortic diameter during the cardiac cycle.
Area of Science:
- Cardiovascular Imaging
- Medical Diagnostics
- Aortic Disease Research
Background:
- Accurate measurement of aortic diameter is crucial for diagnosing and managing cardiovascular conditions.
- Dynamic changes in aortic diameter during the cardiac cycle can influence diagnostic accuracy.
- Comparing different imaging modalities is essential for establishing reliable measurement protocols.
Purpose of the Study:
- To evaluate the consistency of aortic diameter measurements obtained through intraoperative ultrasound (IOUS), computed tomography angiography (CTA), and transthoracic echocardiography (TTE).
- To assess the dynamic changes in ascending aorta diameter during systole and diastole across these imaging techniques.
- To determine the concordance between different imaging methods for aortic diameter assessment.
Main Methods:
- Inclusion of 25 adult patients undergoing cardiac surgery with nonaneurysmal aortas.
- Acquisition of aortic diameter measurements using IOUS, CTA, and TTE.
- Measurement of anteroposterior diameters at specific anatomical landmarks (aortic sinus junction, innominate artery origin, midpoint).
- Analysis of systolic and diastolic diameters and their dynamic changes.
Main Results:
- IOUS measurements of the proximal ascending aorta showed significant dynamic changes between systole and diastole (1.80 mm difference).
- CTA and TTE measurements of the proximal ascending aorta were consistent with IOUS, with high concordance rates (96% for IOUS/CTA, 92% for IOUS/TTE in systole).
- Pearson correlation coefficients between imaging modalities ranged from 0.905 to 0.982, indicating strong agreement.
Conclusions:
- Nonelectrocardiography-gated CTA and TTE provide measurements of ascending aorta diameter that are consistent with IOUS.
- The findings support the reliability of CTA and TTE in assessing aortic dimensions, comparable to IOUS.
- These imaging modalities effectively capture the dynamic nature of aortic diameter changes.
Objective:
This study aimed to examine the relationship between dynamic changes in aortic diameter and corresponding measurement methods.
Methods:
Consecutive adult (nonaneurysmal) patients being surgically treated for heart disease (mean age, 51 ± 11 years; range, 29-76 years; N = 25) were included in this study. All patients underwent transthoracic echocardiography (TTE), computed tomography angiography (CTA), and intraoperative ultrasound (IOUS). Anteroposterior diameters were measured at 1 cm above the junction of the aortic sinus, the proximal 1 cm of the innominate artery, and the midpoint of the two.
Results:
The average diameter of the proximal ascending aorta in systole/diastole measured by IOUS was 32.07 ± 2.03/30.27 ± 2.05 mm (paired t-test: difference, 1.80 ± 0.46 mm; P < .001). The average diameters of the proximal ascending aorta measured by nonelectrocardiography-gated CTA and TTE were 31.45 ± 1.97 mm and 29.7 ± 1.84 mm, respectively. The average diameter of the mid and distal ascending aorta in systole/diastole measured by IOUS was 32.35 ± 1.95/30.57 ± 1.94 mm (paired t-test: difference, 1.78 ± 0.44 mm; P < .001) and 32.32 ± 1.92/30.67 ± 1.90 mm (paired t-test: difference, 1.65 ± 0.42 mm; P < .001), respectively. The average diameter of the mid and distal ascending aorta measured by CTA was 31.74 ± 1.92 mm and 31.59 ± 1.96 mm, respectively. At each location, the difference in the aortic diameter between systole and diastole was statistically significant (all P values <.001; paired t-test). The minimum and maximum changes in the diameter between systole and diastole were 0.90 mm and 2.70 mm. In all, 96% (24/25) of the average diameters derived from IOUS and CTA at the three locations were within the concordance limit in systole, and 92% to 100% (23/25 to 25/25) were within the concordance limit in diastole. The average diameters derived from IOUS and TTE images of the proximal ascending aorta were within the bounds of the concordance limit 92% (23/25) of the time in systole and 100% (25/25) of the time in diastole. The average diameters derived from CTA and TTE images of the proximal ascending aorta were within the bounds of the concordance limit 88% (22/25) of the time. Pearson correlation coefficients between these groups ranged from 0.905 to 0.982 (all P values <.01).
Conclusions:
The ascending aorta diameters measured by nonelectrocardiography-gated CTA and TTE were consistent with the IOUS measurements.
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