Division of Cardiology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa
Division of Cardiology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University and Tygerberg Hospital, Cape Town, South Africa.
Heart. 2023 Jul 27;109(16):1241-1247. doi: 10.1136/heartjnl-2022-322192.
Screening echocardiography, guided by the current World Heart Federation (WHF) criteria, has important limitations that impede the establishment of large-scale rheumatic heart disease (RHD) control programmes in endemic regions. The criteria misclassify a significant number of normal cases as borderline RHD. Prior attempts to simplify them are limited by incorporation bias due to the lack of an externally validated, accurate diagnostic test for RHD. We set out to assess novel screening criteria designed to avoid incorporation bias and to compare this against the performance of the current WHF criteria.
The performance of the WHF and the morpho-mechanistic (MM) RHD screening criteria (a novel set of screening criteria that evaluate leaflet morphology, motion and mechanism of regurgitation) as well as a simplified RHD MM 'rule-out' test (based on identifying a predefined sign of anterior mitral valve leaflet restriction for the mitral valve and any aortic regurgitation for the aortic valve) were assessed in two contrasting cohorts: first, a low-risk RHD cohort consisting of children with a very low-risk RHD profile. and second, a composite reference standard (CRS) RHD-positive cohort that was created using a composite of two criteria to ensure a cohort with the highest possible likelihood of RHD. Subjects included in this group required (1) proven, prior acute rheumatic fever and (2) current evidence of predefined valvular regurgitation on echocardiography.
In the low-risk RHD cohort (n=364), the screening specificities for detecting RHD of the MM and WHF criteria were 99.7% and 95.9%, respectively (p=0.0002). The MM rule-out test excluded 359/364 cases (98.6%). In the CRS RHD-positive cohort (n=65), the screening sensitivities for the detection of definite RHD by MM and WHF criteria were 92.4% and 89.2%, respectively (p=0.2231). The MM RHD rule-out test did not exclude any cases from the CRS RHD-positive cohort.
Our proposed MM approach showed an equal sensitivity to the WHF criteria but with significantly improved specificity. The MM RHD rule-out test excluded RHD-negative cases while identifying all cases within the CRS RHD-positive cohort. This holds promise for the development of a two-step RHD screening algorithm to enable task shifting in RHD endemic regions.
根据当前世界心脏联盟（WHF）标准进行的超声心动图筛查存在重要局限性，这阻碍了在流行地区建立大规模风湿性心脏病（RHD）控制计划。这些标准将相当数量的正常病例误诊为边缘型 RHD。以前尝试简化这些标准的尝试因缺乏外部验证的、准确的 RHD 诊断测试而受到纳入偏倚的限制。我们着手评估旨在避免纳入偏倚的新的筛查标准，并将其与当前 WHF 标准的性能进行比较。
评估了 WHF 和形态力学（MM）RHD 筛查标准（一套评估瓣叶形态、运动和反流机制的新筛查标准）以及简化的 RHD MM“排除”试验（基于识别二尖瓣的前二尖瓣瓣叶限制的预定义标志和主动脉瓣的任何主动脉瓣反流）的性能，在两个对比队列中进行：首先，一个低危 RHD 队列，由具有非常低危 RHD 特征的儿童组成。其次，创建了一个综合参考标准（CRS）RHD 阳性队列，该队列使用两种标准的组合来确保队列具有最高可能的 RHD 可能性。该组纳入的对象需要（1）已证实的既往急性风湿热和（2）当前超声心动图上存在预定义瓣膜反流的证据。
在低危 RHD 队列（n=364）中，MM 和 WHF 标准检测 RHD 的特异性分别为 99.7%和 95.9%（p=0.0002）。MM 排除试验排除了 359/364 例（98.6%）。在 CRS RHD 阳性队列（n=65）中，MM 和 WHF 标准检测明确 RHD 的敏感性分别为 92.4%和 89.2%（p=0.2231）。MM RHD 排除试验并未将任何病例排除在 CRS RHD 阳性队列之外。
我们提出的 MM 方法与 WHF 标准具有相同的敏感性，但特异性显著提高。MM RHD 排除试验排除了 RHD 阴性病例，同时确定了 CRS RHD 阳性队列中的所有病例。这为开发两步 RHD 筛查算法以在 RHD 流行地区实现任务转移提供了希望。
