Abdominal Aorta Screening During Routine Transthoracic Echocardiography in Zanzibar, Tanzania: The Zanzibar Heart Survey.

BACKGROUND AND

OBJECTIVES

Abdominal aortic (AA) aneurysms (AAA) are often incidental findings and preceded by a long period of subclinical growth in diameter. Patients may present with life-threatening complications. Therefore, screening programmes for AAA in primary care are proposed in several European countries, and opportunistic AAA screening during echocardiography is also advocated. However, data on the interest of such an approach in the sub-Saharan African population are unknown.

METHODS

In 2022, a total of 189 patients with cardiac symptoms visiting the Mnazi Mmoja Referral Hospital (MMH) in Zanzibar underwent standard transthoracic echocardiography (TTE). Demographics and clinical data were recorded. AA diameter was routinely assessed in 137 patients. AA was measured by the leading-edge-to-leading-edge method from a longitudinal plane, and AAA was defined as an AA diameter of ≥3.0 cm. SPSS version 29.0 was used for data analysis. The prevalence of AAA was estimated as the number of AAA cases divided by the number of all screened subjects. Correlates of AA diameter were tested in univariate and multivariate linear regression analyses.

RESULTS

AA could be visualized in 128 (93.4%) patients (43% of men and 57% of women). The mean age was 54.4 ± 15.9 years. The mean AA diameter was 2.1 ± 0.3 cm in the entire study population and was significantly greater in men than women (2.2 ± 0.3 vs 2.1 ± 0.3 cm, p = 0.005) and in individuals aged ≥60 years than those aged <60 years (2.3 ± 0.3 vs 2.1 ± 0.3 cm, p = 0.003). The prevalence of AAA was 1.6%. In a multivariate linear regression analysis, higher age, male gender, atrial fibrillation and left ventricular (LV) mass were independent correlates of greater AA diameter, adjusted for clinic systolic blood pressure, ascending aortic diameter and LV ejection fraction (multiple R2 = 0.38, p < 0.001).

CONCLUSIONS

Abdominal aorta screening during routine TTE is feasible in Africa. Patients in Zanzibar have relatively smaller abdominal aorta diameters with a 1.6% prevalence of AAA. Abdominal aorta screening by routine echocardiography may be beneficial, provided that access to care and vascular surgery facility/expertise with appropriate follow-up is available for patients with AAA identified during screening.