What is the clinical significance of an aortic root diameter of 3 centimeters (cm) and an ascending aorta diameter of 2.9 cm, with no pericardial effusion, shunts, pleural effusion, or pacemaker (artificial cardiac pacemaker)?

From the Guidelines

The aortic root diameter of 3 cm and ascending aorta of 2.9 cm are within normal limits, indicating no aortic dilation or aneurysm, and therefore, no immediate surgical intervention is required, as stated in the 2022 aortic disease guideline-at-a-glance 1. The absence of pericardial and pleural effusions suggests no fluid accumulation around the heart or lungs, which is reassuring.

• No cardiac shunts were detected, meaning there are no abnormal connections between heart chambers or blood vessels that could cause oxygen-rich and oxygen-poor blood to mix.
• The absence of a pacemaker indicates that the patient does not currently require artificial assistance to maintain normal heart rhythm. Overall, these findings represent normal cardiac anatomy with no concerning structural abnormalities.
• No specific interventions are needed based on these particular findings, though regular cardiovascular health maintenance through appropriate diet, exercise, and routine medical follow-up remains important, as normal thoracic aorta diameter varies from the aortic sinuses to the diaphragm, decreasing in size as it courses distally, with adult thoracic aorta diameter dependent on the individual, but measures between 3.5 and 4.0 cm at the aortic root, and tapers distally to measure between 2.4 and 2.7 cm at the level of the diaphragm, with larger diameters seen particularly in older males 1. These measurements and observations serve as a good baseline for future comparisons if any cardiac symptoms develop.
• It is essential to note that aortic dilatation of <50% over normal qualifies as aortic ectasia, whereas thoracic aortic aneurysms (TAAs) are diagnosed when there is at least 50% enlargement of the aortic lumen, or alternatively when the aortic diameter is more than two standard deviations above the mean for the patient’s sex and age 1. Based on the most recent guidelines, the patient's aortic root diameter and ascending aorta measurements do not meet the surgical intervention thresholds, and therefore, conservative management and regular follow-up are recommended 1.

From the Research

Aortic Root and Ascending Aorta Diameters

• The aortic root diameter is 3 cm and the ascending aorta diameter is 2.9 cm, which are important measurements for assessing aortic health 2.
• These diameters are within the range of normal values for healthy adults, but may be considered dilated in certain individuals, particularly those with a family history of aortic disease or certain genetic conditions 2.

Comparison to Normal Values

• A study of 1,043 healthy adults found that the absolute aortic diameters were significantly greater in men than in women at all levels, whereas body surface area-indexed aortic diameters were greater in women 2.
• The same study found a straight correlation between aortic diameters and age in both genders, suggesting that aortic diameter increases with age 2.

Measurement Conventions

• There are different conventions for measuring aortic root and ascending aorta diameters, including the diastolic leading edge (DLE) and systolic inner edge (SIE) conventions 3.
• A study comparing these conventions found that they yielded similar values, with a non-significant underestimation of the diameter measured by the SIE convention at the root level and at the tubular ascending aorta level 3.

Medical Prophylaxis

• Medical prophylaxis, such as treatment with losartan or atenolol, has been shown to reduce proximal aortic growth rates in young patients with at least moderate and progressive bicuspid aortopathy 4.
• Angiotensin receptor blockers (ARBs) have also been found to slow down the progression of aortic dilatation in patients with Marfan syndrome, a genetic disorder that affects the aorta 5.

Treatment and Management

• Surgery is the primary treatment for aortic root aneurysms, but medical therapy and other interventions may also be used to manage the condition and prevent complications 6.
• The choice of treatment depends on various factors, including the size and location of the aneurysm, as well as the patient's overall health and medical history 6.