经胸超声心动图判断左心室流出道梗阻对经皮主动脉瓣置换术的意义

The role of Left ventricle outflow tract obstruction diagnosed by transthoracic echocardiography in transcatheter aortic valve replacement

目的:比经皮主动脉瓣置换术(TAVI)是高危主动脉瓣病变患者的有效治疗手段。本研究通过TAVI合并左心室流出道梗阻(LVOTO)的特殊病例,探讨经胸超声心动图(TTE)术前及术后诊断LVOTO对于TAVI的临床意义。方法:2018年7月至2020年6月间,于我院接受经股动脉TAVI手术的主动脉瓣狭窄患者226例。对接受TAVI患者在围术期进行左心室流出道(LVOT)形态及流速探查。结果:共6例患者出现LVOTO。2例患者TAVI手术的术前发现LVOTO,其室间隔基底段呈明显乙状室间隔,SAM征阳性,术后其LVOTO未见缓解。3例患者术前LVOT的流速正常,术后即刻出现LVOTO,其左心室室壁明显增厚,运动增强,左心室容积偏小,术后SAM阳性,经控制血压及心率治疗后,LVOTO缓解,流速恢复正常。1例患者术前LVOT流速正常,术后LVOT流速正常,左心室腔中部的中位LVOT出现流速明显增快,经治疗后缓解。结论:进行TAVI手术的患者多表现为左心室室壁增厚,左心室容积偏小,室间隔形态改变,易于出现LVOTO。TTE是检出LVOTO的有效手段,应于术前仔细探查,术后注意监测。

Objective:Transcatheter aortic valve implantation(TAVI)is an effective way to the aortic stenosis(AS)patients in high surgical risks.Because of the features of transcatheter operation,the inspection of left ventricle outflow tract obstruction(LVOTO)is critical to TAVI.Transthoracic echocardiography(TTE)is important in the diagnosis of LVOTO.This study was to discuss the role of TTE in diagnosing LVOTO just before and after TAVI immediately.Mehtods:226 AS patients received TAVI from July 2018 to June 2020 were included.TTE was used just before and after TAVI to detect LVOTO.Morphological characteristics of left ventricle,sigmoid interventricular septum,ventricular wall motion,LVOT velocity and pressure gradient were detected.Results:LVOTO was detected in 2 patients before the operation and maintained after TAVI.Sigmoid interventricular septum and SAM were present.Another 3 patients were diagnosed as LVOTO after TAVI immediately,with normal LVOT velocity before the operation.LV wall was hypertrophic and in hyperkinetic state,LV end-diastolic volume was reduced.LVOTO was relieved after the treatment of hypertension.Obstruction in the middle left ventricle with normal LVOT velocity was found in one patient.The obstruction was relieved after heart rate control and hypervolemic treatment.Conclusions:LV wall hypertrophy,sigmoid interventricular septum,and reduced LV volume is often observed in AS patients undergoing TAVI.TTE is an important method to diagnose LVOTO.TTE examination before and after operation is critical to TAVI,while special attention should be paid to this phenomenon.