左心房容积与直径评估二尖瓣狭窄血栓栓塞风险的作用。

Usefulness of left atrial volume versus diameter to assess thromboembolic risk in mitral stenosis.

机构信息

Cardiology Department, AP-HP, Bichat Hospital, Paris, France.

出版信息

Am J Cardiol. 2010 Oct 15;106(8):1152-6. doi: 10.1016/j.amjcard.2010.06.024.

DOI:10.1016/j.amjcard.2010.06.024

PMID:20920656

Abstract

In patients with mitral stenosis (MS) in sinus rhythm (SR), guidelines recommend anticoagulation if the left atrium is enlarged based on diameter measurements. We sought to compare the association of left atrial (LA) diameter and LA volume with markers of thromboembolic risk (peak LA appendage emptying velocity [LAAv] and LA spontaneous contrast density) measured during transesophageal echocardiography in 152 patients with moderate to severe MS. High thromboembolic risk was defined by a peak LAAv < 25 cm/s and/or dense spontaneous contrast. Mean LA diameter (50 ± 7 mm, 32 to 77) and LA volume (152 ± 70 ml, 67 to 720) were significantly correlated (r = 0.71, p < 0.0001), but the relation was curvilinear and the 95% confidence interval increased with LA diameter. In the subset of 80 patients in SR who underwent clinically indicated transesophageal echocardiography, body surface area (BSA)-indexed LA volume but not LA diameter differentiated patients with normal from those with low LAAv (86 ± 17 vs 71 ± 17 ml/m(2), p < 0.01, and 50 ± 6 vs 48 ± 6 mm, p = 0.13, respectively) and patients with dense spontaneous contrast from those with no or mild spontaneous contrast (81 ± 16 vs 63 ± 15 ml/m(2), p < 0.01, and 49 ± 6 vs 46 ± 5 mm, p = 0.11, respectively). BSA-indexed LA volume provided the highest area under the curve (0.85) for high thromboembolic risk and LA diameter the lowest (0.65). A BSA-indexed LA volume > 60 ml/m(2) provided an excellent 90% sensitivity despite 44% specificity, 76% positive predictive value, and 70% negative predictive value. Use of this threshold instead of 50 or 55 mm would have changed the indication for anticoagulation in 51% to 77% of patients. In conclusion, LA volume was more strongly associated with markers of thromboembolic risk than LA diameter, which poorly reflected LA size. Our results support the use of BSA-indexed LA volume to guide the decision for anticoagulation in patients with MS in SR, which may lead to significant change in the management of those patients. We suggest a threshold of 60 ml/m(2), which has good sensitivity, albeit with low specificity.

摘要

在窦性心律（SR）的二尖瓣狭窄（MS）患者中，如果根据直径测量结果左心房（LA）扩大，则指南建议抗凝。我们试图比较 152 例中重度 MS 患者经食管超声心动图（TEE）测量的左房（LA）直径和 LA 容积与血栓栓塞风险标志物（LA 瓣口排空速度峰值 [LAAv] 和 LA 自发性对比密度）之间的关系。高血栓栓塞风险定义为 LAAv < 25 cm/s 和/或密集自发性对比。平均 LA 直径（50 ± 7 mm，32 至 77）和 LA 容积（152 ± 70 ml，67 至 720）显著相关（r = 0.71，p < 0.0001），但关系呈曲线关系，95%置信区间随 LA 直径增加而增加。在 80 例接受临床指示 TEE 的 SR 患者亚组中，体表面积（BSA）指数化 LA 容积而非 LA 直径可区分 LAAv 正常与低 LAAv（86 ± 17 与 71 ± 17 ml/m2，p < 0.01）和 LA 自发性对比密集与无或轻度自发性对比（81 ± 16 与 63 ± 15 ml/m2，p < 0.01）的患者。BSA 指数化 LA 容积对高血栓栓塞风险具有最高的曲线下面积（0.85），而 LA 直径最低（0.65）。BSA 指数化 LA 容积 > 60 ml/m2 提供了出色的 90%敏感性，尽管特异性为 44%、阳性预测值为 76%和阴性预测值为 70%。使用该阈值而不是 50 或 55 mm 将改变 51%至 77%患者的抗凝指征。总之，LA 容积与血栓栓塞风险标志物的相关性强于 LA 直径，而 LA 直径不能很好地反映 LA 大小。我们的结果支持使用 BSA 指数化 LA 容积来指导 SR 中 MS 患者的抗凝决策，这可能会导致这些患者的治疗方式发生重大变化。我们建议使用 60 ml/m2 的阈值，该阈值具有良好的敏感性，尽管特异性较低。