Background

Aortic regurgitation (AR) is a complex and multifactorial valvular disease. The association between aortic root dimensions and the degree of AR is still controversial.

Aim

To evaluate the prevalence of AR and the association between aortic root dimensions measured in end-diastole and mid-systole with AR severity in a large sample of the population-based Hamburg City Health cohort Study (HCHS). 

Methods and Results 

In 8259 HCHS participants (51.3% females, mean age 62.23 ± 8.46 years), enrolled between 2016 and 2019, standardised transthoracic echocardiography was performed. Aortic root dimensions, including the aortic annulus, sinus of Valsalva, sinotubular junction (STJ), and ascending aorta, were systematically measured both in end-diastole and mid-systole, and AR severity was quantified. We excluded 92 subjects due to moderate/severe aortic stenosis or bicuspid aortic valve. 

A total of 7007 (85.8%) subjects had no AR, 932 (11.4%) subjects showed mild AR, 208 (2.5%) had moderate AR and 20 subjects (0.24%) demonstrated severe AR. Patients with moderate or severe AR (n=228) were predominantly male at advanced age who had a higher prevalence of hypertension, known coronary artery disease, atrial fibrillation, and renal dysfunction. Weight, height, body surface area (BSA), LDL-cholesterol, high-sensitivity C-reactive protein (hsCRP) were comparable among the subgroups. Echocardiography revealed significantly impaired biventricular function and dilated left-sided cavities in subjects with moderate/severe AR as well as higher prevalence of diastolic dysfunction (higher E/e’ ratio). 

Increasing severity of AR was associated with a rise of all end-diastolic and mid-systolic aortic root diameters (e.g., end-diastolic sinus of Valsalva for no-mild-moderate-severe AR in mm ± standard deviation: 34.06±3.81; 35.65±4.13; 36.13±4.74; 39.67±4.61; p<0.001). Indexing to BSA did not change this correlation. In binary logistic regression analysis, adjusted for age, sex, BSA, hypertension, and diabetes, all end-diastolic and mid-systolic aortic root variables showed significant associations with moderate/severe AR, also after correcting for multiple testing (central illustration). Mid-systolic STJ showed the strongest association with moderate/severe AR (OR 1.33, 95% confidence interval 1.25-1.43, p<0.001). 

Conclusions

We found an AR prevalence of 14.1% in the large population based HCHS cohort. All assessed aortic root diameters correlated significantly with the prevalence and severity of AR. In our study cohort of middle-aged to older subjects with tricuspid aortic valves, STJ diameter had the strongest association with a moderate/severe AR. This finding might reflect the pathophysiological impact of increasingly dilated STJ in the context of aging aorta.

Central illustration. Forest plot showing the associations between aortic root dimensions and moderate/severe aortic regurgitation. Odds ratios derived from binary logistic regression analysis adjusted for age, sex, body surface area, hypertension, and diabetes with Holm corrected p-values. Squares and horizontal lines represent odds ratios and 95% confidence intervals. Abbreviations: Ao = aortic; AR = aortic regurgitation; Asc = ascending; CI = confidence interval; ED = end-diastolic; MS = mid-systolic; OR = odds ratio; STJ = sinotubular junction.