Analysis of the discriminative capacity of aortic valve calcification and aortic valve calcification density in the diagnosis of degenerative aortic stenosis in a brazilian cohort

Abstract Introduction Echocardiogram is the test of choice to determine the etiology and anatomical severity of aortic stenosis (AS), although aortic valve calcification (AVC) measures by computed tomography can provide additional information. A novel parameter, AVC density (AVCd), which correlates AVC with the area of the aortic annulus (AA), has demonstrated a stronger association with both the severity and prognosis of AS compared to AVC alone. While reference values for AVCd have been established in European populations, variations in these values have been observed in other populations. The aim of this study was to evaluate the discriminatory capacity of AVC and AVCd for diagnosing degenerative AS in a Brazilian cohort. Methods Single-center, retrospective study, which included 587 consecutive patients with severe (451), moderate (71) and low-flow, low-gradient (LFLG 65) AS. All patients underwent both echocardiography and aortic angiotomography within a maximum interval of 12 months. AVCd was calculated using the formula: AVC (AU) / AA (cm²). Results Men (n=290, 49.4%) were younger than women (78 72-84 vs 80 74-85 years, p=0.003) and had a larger body surface area (1.86 1.74-1.95 vs 1.63 1.52-1.75 m², p0.001), There were no significant differences in comorbidities, such as diabetes (39.3% vs. 34.5%, p=0.264) and hypertension (79% vs. 82%, p=0.067). Echocardiographic findings revealed similar left ventricular ejection fraction (LVEF) between genders (60 54-64 in men vs 62 57.2-66 % in women, p0.001). Aortic valve area was significantly different between genders (0.8 0.7-0.9 cm² in men vs. 0.7 0.6-0.8 cm² in women, p0.001), but no difference was found when indexed (0.41 0.35-0.5 cm² in men vs. 0.41 0.35-0.5 cm² in women, p=0.617). In the tomography, the AA was larger in men (4.92 4.5-5.5 vs 4.00 3.5-4.4 cm², p0.001). Regarding the types of AS, 45 men (15.5%) had moderate AS, 209 (72.1%) had severe AS, and 36 (12.4%) had low-flow, low-gradient (LFLG) AS. In women, fewer had moderate AS (12.4%), more had severe AS (81.5%), and a similar proportion had LFLG AS (9.8%). The discriminatory ability of AVC and AVCd was similar (Figure 1 A and B). Using the Youden index, cut-off values were defined for AVC (2501 AU in men and 2050 AU in women) and AVCd (501 AU/cm² in men and 494 AU/cm² in women), showing different sensitivity and specificity compared to previously established values in the literature (Figure 2). Conclusion Aortic valve calcification in a Brazilian population exhibits distinct patterns, with significantly higher levels of calcification in women compared to existing literature. The median values and cut-off points associated with the anatomical severity of aortic stenosis (AS) differ from those observed in European and North American populations. These findings highlight the need for further studies to better understand these patterns and refine AS diagnosis and treatment strategies for diverse populations.Discriminative capacity of AVC and AVCd AVC and AVCd values and correlations