Department of Radiological Sciences, David Geffen School of Medicine at UCLA, Los Angeles, Calif. 90095, USA.
Circ Cardiovasc Imaging. 2010 Nov;3(6):687-93. doi: 10.1161/CIRCIMAGING.110.959171. Epub 2010 Sep 16.
remodeling of the mitral annulus contributes to progression of mitral regurgitation (MR). In patients with moderate-to-severe MR, short-term treatment with β-blockers has been shown to increase left ventricular (LV) end-diastolic and end-systolic volume, and this could deleteriously increase mitral valve annular dimensions. The objective of this study was to quantify the effects of a short duration of β-blocker treatment on mitral annular dimensions and dynamics in patients with MR due to primary degenerative valve disease.
twenty-five patients with moderate-to-severe degenerative MR and normal LV systolic function were studied in a double-blind crossover experiment using a β1-selective adrenergic blocker and placebo administered for 14±3 days. Cardiac MRI images were acquired after each treatment period to quantify mitral annular dimensions. At end diastole, there was no change in annular area (1659±331 versus 1632±299 mm(2); P<0.19), annular perimeter (154.3±16.4 versus 152±13.9 mm; P<0.13), septal-lateral (SL) dimension (38.0±5 versus 39.0±4.5 mm; P<0.15), or annular height (9.8±3.8 versus 9.5±2.5 mm; P<0.53). β-blockade resulted in significant end-diastole decreases in commissure-commissure dimension (48.9±4.6 versus 47.2±4.0 mm; P<0.01) and eccentricity (1.3±0.2 versus 1.2±0.1; P<0.01). At end systole (ES), β-blockade conferred a small, but significant decrease in annular perimeter (161.0±19.3 versus 156.8±16.9 mm; P<0.04) and eccentricity (1.2±0.1 versus 1.1±0.1; P<0.02), and the SL dimension significantly increased (41.5±5.7 versus 43.0±5.3 mm; P<0.03). Commissure-commissure dimension, annular area, and annular height at ES were not significantly different.
despite significant increases in LV end-diastolic and end-systolic volume, short-term β-blocker treatment of patients with moderate-to-severe MR reduced or preserved all mitral annular dimensions except SL at ES.
二尖瓣环重构导致二尖瓣反流（MR）进展。在中重度 MR 患者中，短期使用β受体阻滞剂治疗已被证明会增加左心室（LV）舒张末期和收缩末期容积，这可能会增加二尖瓣环的尺寸，从而对其产生不良影响。本研究的目的是定量评估短期β受体阻滞剂治疗对原发性退行性瓣膜病所致 MR 患者二尖瓣环尺寸和动力学的影响。
25 例中重度退行性 MR 且左心室收缩功能正常的患者接受了一项双盲交叉实验，在此实验中，患者分别接受β1 选择性肾上腺素能阻滞剂和安慰剂治疗 14±3 天。在每个治疗期结束后，使用心脏 MRI 图像来量化二尖瓣环尺寸。在舒张末期，瓣环面积（1659±331 与 1632±299mm²；P<0.19）、瓣环周长（154.3±16.4 与 152±13.9mm；P<0.13）、间隔-侧壁（SL）径线（38.0±5 与 39.0±4.5mm；P<0.15）或瓣环高度（9.8±3.8 与 9.5±2.5mm；P<0.53）均无明显变化。β受体阻滞剂治疗后，瓣环交界处-交界处径线（48.9±4.6 与 47.2±4.0mm；P<0.01）和偏心度（1.3±0.2 与 1.2±0.1；P<0.01）显著减小。在收缩末期（ES），β受体阻滞剂治疗使瓣环周长（161.0±19.3 与 156.8±16.9mm；P<0.04）和偏心度（1.2±0.1 与 1.1±0.1；P<0.02）略有减小，SL 径线显著增大（41.5±5.7 与 43.0±5.3mm；P<0.03）。ES 时瓣环交界处-交界处径线、瓣环面积和瓣环高度无显著差异。
尽管 LV 舒张末期和收缩末期容积显著增加，但中重度 MR 患者短期β受体阻滞剂治疗除 ES 时 SL 外，其余所有二尖瓣环尺寸均减小或保持不变。
