Division of Cardiology, Department of Medicine, Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada.
JACC Cardiovasc Interv. 2011 Sep;4(9):1030-4. doi: 10.1016/j.jcin.2011.06.008.
The purpose of this study was to investigate whether a relationship exists between an acute reduction in resting left ventricular outflow tract (LVOT) gradient with balloon occlusion and the final invasive gradient response following alcohol septal ablation (ASA).
ASA is an alternative therapy to myectomy surgery to reduce the basal septal thickness and decrease the resting and/or provocable LVOT gradient in patients with hypertrophic cardiomyopathy. Patients have a variable gradient response to occlusion of the septal perforator artery before ethanol infusion for ASA.
From November 1998 to November 2008, 120 patients (mean age 60 years [range 16 to 87 years], 50% women) with hypertrophic cardiomyopathy underwent ASA at our institution. The resting LVOT gradient (peak systolic left ventricle [LV] pressure - peak systolic aortic pressure) was measured continuously during the ASA procedure. The time to significant LVOT gradient decrease (defined as >50% decrease from baseline) was recorded following balloon occlusion of the dominant septal perforator coronary artery, which was found to perfuse the basal septum based on contrast echocardiographic studies.
The mean baseline resting LVOT gradient was 86 ± 43 mm Hg, and it decreased to 17 ± 11 mm Hg following ASA (-80.2%). The mean time to significant gradient reduction was 3.6 ± 2 min (range 25 s to 11 min). The time to significant LVOT gradient reduction strongly correlated with the final magnitude of gradient reduction following ASA (r = -0.81, p < 0.001).
This study demonstrates a correlation between the time to significant LVOT gradient reduction following septal perforator balloon occlusion and the magnitude of final gradient response after ASA.
本研究旨在探讨球囊阻塞时左心室流出道（LVOT）静息梯度的急性降低与酒精室间隔消融（ASA）后最终侵入性梯度反应之间是否存在关系。
ASA 是心肌梗死后室间隔切除术的替代治疗方法，可减少基底部室间隔厚度并降低肥厚型心肌病患者的静息和/或可诱发的 LVOT 梯度。在进行乙醇输注以进行 ASA 之前，在闭塞间隔穿通动脉时，患者对闭塞的梯度反应存在差异。
1998 年 11 月至 2008 年 11 月，我院 120 例肥厚型心肌病患者（平均年龄 60 岁[范围 16 至 87 岁]，50%为女性）接受 ASA。ASA 过程中连续测量静息 LVOT 梯度（左心室收缩峰值压力-主动脉收缩峰值压力）。在发现基于对比超声心动图研究可灌注基底部间隔的优势间隔穿通动脉球囊闭塞后，记录从基线开始 LVOT 梯度显著降低（定义为从基线下降>50%）的时间。
静息 LVOT 梯度的平均基线值为 86 ± 43 mm Hg，ASA 后降至 17 ± 11 mm Hg（-80.2%）。显著梯度降低的平均时间为 3.6 ± 2 分钟（范围 25 秒至 11 分钟）。LVOT 梯度显著降低的时间与 ASA 后最终梯度降低的幅度密切相关（r = -0.81，p <0.001）。
本研究表明，间隔穿通动脉球囊闭塞后 LVOT 梯度显著降低的时间与 ASA 后最终梯度反应幅度之间存在相关性。
