Innere Medizin III, Universitätsklinikum Schleswig-Holstein, Kiel, Germany.
Medizinische Klinik I, Klinikum Aschaffenburg-Alzenau, Aschaffenburg, Germany.
Eur J Clin Invest. 2020 Oct;50(10):e13295. doi: 10.1111/eci.13295. Epub 2020 Jun 22.
The MitraClip procedure requires transseptal access of the left atrium with a 24F guiding sheath. We evaluated invasively whether a MitraClip induced iatrogenic atrial septal defect (IASD) leads to development of a relevant interatrial shunt and right ventricular overload.
A total of 69 patients who underwent a MitraClip procedure due to a severe mitral valve regurgitation (MVR) were included in the observational, retrospective cohort study. All pressures were directly measured throughout the procedure. Cardiac index (CI), systemic (Qs) and pulmonary (Qp) flow were calculated using the Fick method.
Successful MitraClip implantation increased CI (2.5 ± 0.62 vs 3.05 ± 0.77 L/min/m ; P < .0001), whereas SVR (1491 ± 474 vs 997 ± 301 dyn s/cm ; P < .0001), PVR (226 ± 121 vs 188 ± 96 dyn/s/cm ; P = .04), PCWP (23 ± 6.1 vs 20 ± 4.7 mm Hg; P = .0031), PA pressure (33.6 ± 7.2 vs 31.9 ± 6.6 mm Hg; P = .1437) and LA pressure (21.5 ± 5.4 vs 18.7 ± 4.9 mm Hg; P < .0001) all decreased. The effect on LA pressure was further enhanced by guiding catheter retrieval (14.4 ± 4.6 mm Hg; P < .0001). At the end of the procedure, Qp (6.033 ± 1.3 L/min) exceeded Qs (5.537 ± 1.3 L/min) by 0.496 L/min leading to a Qp:Qs ratio of 1.09 (P = .007). After 6 months, echocardiography revealed no changes in RV diameter (42.96 ± 6.95 mm vs 43.81 ± 7.67 mm; P = .62) and TAPSE (17.13 ± 3.33 mm vs 17.36 ± 3.24 mm; P = .48).
Our data show that the MitraClip procedure does not induce a relevant interatrial shunt or right ventricular overload. In fact, future studies will have to show whether the IASD may even be beneficial in selected patient populations by left atrial volume and pressure relief.
MitraClip 手术需要经 24F 引导鞘管进入左心房。我们通过侵入性评估来确定经 MitraClip 治疗引起的医源性房间隔缺损（IASD）是否会导致相关的房间隔分流和右心室超负荷。
本观察性回顾性队列研究共纳入 69 例因严重二尖瓣反流（MVR）而行 MitraClip 手术的患者。整个手术过程中直接测量所有压力。心指数（CI）、体循环（Qs）和肺循环（Qp）流量采用 Fick 法计算。
成功植入 MitraClip 可增加 CI（2.5±0.62 比 3.05±0.77 L/min/m；P<0.0001），同时降低全身血管阻力（SVR）（1491±474 比 997±301 dyn s/cm；P<0.0001）、肺血管阻力（PVR）（226±121 比 188±96 dyn/s/cm；P=0.04）、肺动脉压（33.6±7.2 比 31.9±6.6 mm Hg；P=0.1437）和左心房压（21.5±5.4 比 18.7±4.9 mm Hg；P<0.0001）。进一步通过回收引导导管，LA 压降低更为明显（14.4±4.6 mm Hg；P<0.0001）。手术结束时，Qp（6.033±1.3 L/min）比 Qs（5.537±1.3 L/min）高 0.496 L/min，导致 Qp:Qs 比值为 1.09（P=0.007）。6 个月后，超声心动图显示右心室直径（42.96±6.95 mm 比 43.81±7.67 mm；P=0.62）和 TAPSE（17.13±3.33 mm 比 17.36±3.24 mm；P=0.48）无变化。
我们的数据表明，MitraClip 手术不会引起明显的房间隔分流或右心室超负荷。事实上，未来的研究将不得不表明，在选定的患者人群中，IASD 是否通过左心房容积和压力减轻而具有益处。
