Department of Cardiology, VU University Medical Center, Amsterdam, the Netherlands.
J Cardiovasc Magn Reson. 2010 Mar 15;12(1):13. doi: 10.1186/1532-429X-12-13.
Clinical data on myocardial function in HCM mutation carriers (carriers) is sparse but suggests that subtle functional abnormalities can be measured with tissue Doppler imaging before the development of overt hypertrophy. We aimed to confirm the presence of functional abnormalities using cardiovascular magnetic resonance (CMR), and to investigate if sensitive functional assessment could be employed to identify carriers.
28 carriers and 28 controls were studied. Global left atrial (LA) and left ventricular (LV) dimensions, segmental peak systolic circumferential strain (SCS) and peak diastolic circumferential strain rate (DCSR), as well as the presence of late Gadolinium enhancement (LGE) were determined with CMR. Septal and lateral myocardial velocities were measured with echocardiographic tissue Doppler imaging. LV mass and volumes were comparable between groups. Maximal septal to lateral wall thickness ratio (SL ratio) was larger in carriers than in controls (1.3+/-0.2 versus 1.1+/-0.1, p<0.001). Also, LA volumes were larger in carriers compared to controls (p<0.05). Both peak SCS (p<0.05) and peak DCSR (p<0.01) were lower in carriers compared to controls, particularly in the basal lateral wall. Focal LGE was present in 2 carriers and not in controls. The combination of a SL ratio>1.2 and a peak DCSR<105%.s-1 was present in 45% of carriers and in none of the controls, yielding a positive predictive value of 100%. Two carriers and 18 controls had a SL ratio<1.2 and peak DCSR>105%.s-1, yielding a negative predictive value of 90%. With multivariate analysis, HCM mutation carriership was an independent determinant of reduced peak SCS and peak DCSR.
HCM mutation carriership is an independent determinant of reduced peak SCS and peak DCSR when LV wall thickness is within normal limits, and is associated with increased LA volumes and SL ratio. Using SL ratio and peak DCSR has a high accuracy to identify carriers. However, since carriers also display structural abnormalities and focal LGE, we advocate to also evaluate morphology and presence of LGE when screening for carriers.
肥厚型心肌病（HCM）突变携带者的心肌功能临床数据很少，但提示在明显肥大发生之前，组织多普勒成像可以测量到微妙的功能异常。我们旨在使用心血管磁共振（CMR）证实存在功能异常，并研究敏感的功能评估是否可用于识别携带者。
研究了 28 名携带者和 28 名对照者。使用 CMR 确定了左心房（LA）和左心室（LV）的整体尺寸、节段性峰值收缩周向应变（SCS）和峰值舒张周向应变率（DCSR），以及晚期钆增强（LGE）的存在。使用超声心动图组织多普勒成像测量了间隔和侧壁心肌速度。LV 质量和容量在两组之间相似。携带者的最大间隔到侧壁厚度比（SL 比）大于对照组（1.3±0.2 与 1.1±0.1，p<0.001）。此外，携带者的 LA 容积大于对照组（p<0.05）。与对照组相比，携带者的峰值 SCS（p<0.05）和峰值 DCSR（p<0.01）均较低，尤其是在基底侧壁。2 名携带者存在局灶性 LGE，而对照组没有。SL 比>1.2 和峰值 DCSR<105%.s-1 的组合存在于 45%的携带者中，而对照组中不存在，阳性预测值为 100%。2 名携带者和 18 名对照组的 SL 比<1.2 和峰值 DCSR>105%.s-1，阴性预测值为 90%。多变量分析显示，HCM 突变携带者是 LV 壁厚度正常范围内峰值 SCS 和峰值 DCSR 降低的独立决定因素。
当 LV 壁厚度在正常范围内时，HCM 突变携带者是峰值 SCS 和峰值 DCSR 降低的独立决定因素，与 LA 容积增加和 SL 比增加相关。使用 SL 比和峰值 DCSR 具有很高的准确性来识别携带者。然而，由于携带者也显示出结构异常和局灶性 LGE，因此我们主张在筛选携带者时，也评估形态和 LGE 的存在。
