Background

Changes in mitral valve anatomy contribute to left ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy (HCM). Mitral annular calcification (MAC) is common among patients with HCM but its implications are currently unknown.

Methods

We tested the hypothesis that echocardiographic MAC would be associated with anterior displacement of the mitral valve and LVOTO in a cohort of 304 patients with HCM aged ≥ 60 years (mean [SD] age 71.6 [7.7] years, 52% women).

Results

MAC was present in 141 (46%) patients. The mean (SD) MAC offset distance was 9.8 (4.8) mm. A higher proportion of those with MAC compared to those without MAC had SAM (84.2 vs. 63.8%, p < 0.001) and LVOTO (80.9 vs. 57.9%, p < 0.001). In patients with MAC, the septal-mitral valve distance was shorter compared to those without (19.4 [4.0] vs 21.5 [4.9] mm, p < 0.001). The mitral valve position ratio was greater in those with MAC compared to those without (1.00 [0.79, 1.22] vs. 0.86 [0.67, 1.05], p < 0.001) denoting greater anterior displacement, especially in those with MAC and LVOTO. After multivariable adjustment, MAC offset distance was associated with LVOTO (OR 1.16 [95% CI 1.07, 1.28] per mm, p = 0.001). Over a median follow-up of 2.7 years, 42 (29.8%) patients with MAC underwent surgery to relieve LVOTO, with no deaths.

Conclusion

This study adds MAC to the known geometrical alterations of the mitral valve that predispose to LVOTO and suggests that surgical relief of LVOTO in the presence of MAC is safe when performed by an experienced surgeon.

中文翻译：

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肥厚型心肌病二尖瓣环钙化

背景

二尖瓣解剖结构的变化导致肥厚型心肌病 (HCM) 中的左心室流出道梗阻 (LVOTO)。二尖瓣环钙化 (MAC) 在 HCM 患者中很常见，但其影响目前尚不清楚。

方法

我们在 304 名年龄 ≥ 60 岁的 HCM 患者（平均 [SD] 年龄 71.6 [7.7] 岁，52% 为女性）中检验了超声心动图 MAC 与二尖瓣前移和 LVOTO 相关的假设。

结果

141 名 (46%) 患者存在 MAC。平均 (SD) MAC 偏移距离为 9.8 (4.8) mm。与没有 MAC 的患者相比，患有 MAC 的患者有更高比例的 SAM（84.2 对 63.8%，p  < 0.001）和 LVOTO（80.9 对 57.9%，p  < 0.001）。在 MAC 患者中，与没有 MAC 的患者相比，间隔二尖瓣距离更短（19.4 [4.0] 对 21.5 [4.9] mm，p  < 0.001）。与没有 MAC 的患者相比，MAC 患者的二尖瓣位置比更大（1.00 [0.79, 1.22] vs. 0.86 [0.67, 1.05]，p  < 0.001），表明前移更大，尤其是在 MAC 和 LVOTO 患者中。多变量调整后，MAC 偏移距离与 LVOTO 相关（OR 1.16 [95% CI 1.07, 1.28] 每毫米，p = 0.001)。在 2.7 年的中位随访中，42 名 (29.8%) 的 MAC 患者接受了解除 LVOTO 的手术，没有死亡。

结论

这项研究将 MAC 添加到易于发生 LVOTO 的二尖瓣的已知几何改变中，并表明在 MAC 存在的情况下，由经验丰富的外科医生进行 LVOTO 手术缓解是安全的。