Background

American and European societies recommend using left atrial (LA) volume adjusted to body surface area (BSA) as the means of indexing LA volume to the patient's body size irrespective of morphometric characteristics.

Aim

To evaluate the impact of obesity on LA volume indexation to BSA on the presence and degree of LA enlargement.

Methods

From our echocardiography database, we extracted all consecutive adults referred for a transthoracic echocardiography in 2019 (n = 28,725; 64 ± 17 years; 55% male; 31% obese [body mass index ≥ 30 kg/m²]). LA volume indexed to BSA was calculated using measured weight (LA_Meas) and ideal weight (LA_Ideal) calculated using the Devine Formula.

Results

LA_Meas and LA_Ideal were 35 ± 17 mL/m² and 40 ± 19 mL/m², respectively (P < 0.0001); 13% were classified as having a normal LA_Meas but LA_Ideal enlargement overall, 25% in obese patients and 7% in non-obese patients (P < 0.0001). The percentages of patients with no, mild, moderate and severe LA dilatation were 57%, 19%, 9% and 16%, respectively, using LA_Meas, and 45%, 20%, 11% and 24%, respectively, using LA_Ideal (kappa = 0.57). Degree of LA enlargement differed in 8194 patients (29%); 96% of the disagreement was related to underestimation of the degree of LA enlargement using LA_Meas. Agreement for the degree of LA enlargement was poor in obese and good in non-obese patients (kappa = 0.28 and 0.71, respectively). As illustrative clinical implications, diastolic function grade was modified in 8.3% of patients with preserved ejection fraction and 10.8% of patients with reduced left ventricular ejection fraction/myocardial disease, and timing for intervention was potentially different in 12.9% of patients with primary mitral regurgitation.

Conclusions

Indexing LA volume to measured BSA versus ideal BSA markedly underestimates the presence and severity of LA enlargement, especially in obese patients, with potential important clinical implications.

中文翻译：

---

左心房大小调整的临床意义：肥胖的影响

背景

美国和欧洲协会建议使用根据体表面积 (BSA) 调整的左心房 (LA) 容积作为将 LA 容积与患者体型联系起来的方法，而不管形态学特征如何。

目的

评估肥胖对 LA 体积指数对 BSA 的影响对 LA 扩大的存在和程度的影响。

方法

从我们的超声心动图数据库中，我们提取了 2019 年所有连续接受经胸超声心动图检查的成人（n  =  28,725；64  ±  17 岁；55% 男性；31% 肥胖 [体重指数 ≥  30  kg/m ² ]）。使用测量的重量 (LA _Meas ) 和使用 Devine 公式计算的理想重量 (LA _Ideal ) 计算与 BSA 相关的 LA 体积。

结果

LA _Meas和 LA _Ideal分别为 35  ±  17  mL/m ²和 40  ±  19  mL/m ² ( P  <  0.0001)；13% 被归类为 LA _Meas正常但总体LA_理想增大，肥胖患者为 25%，非肥胖患者为 7% ( P  <  0.0001)。使用 LA _Meas时无、轻度、中度和重度 LA 扩张的患者百分比分别为 57%、19%、9% 和 16%，使用 LA 的比例分别为45%、20%、11% 和 24%_理想（kappa  = 0.57）。8194 名患者 (29%) 的 LA 扩大程度不同；96% 的分歧与使用 LA _Meas低估 LA 扩大程度有关。LA 扩大程度的一致性在肥胖患者中较差，在非肥胖患者中较好（kappa 值分别 为 0.28 和 0.71）。作为说明性临床意义，8.3% 的射血分数保留患者和 10.8% 的左心室射血分数降低/心肌疾病患者的舒张功能等级被修改，12.9% 的原发性二尖瓣关闭不全患者的干预时机可能不同.

结论

将 LA 体积与测量的 BSA 与理想的 BSA 进行索引明显低估了 LA 扩大的存在和严重程度，尤其是在肥胖患者中，具有潜在的重要临床意义。