Cardiac Ultrasound Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Am J Cardiol. 2011 Dec 15;108(12):1714-20. doi: 10.1016/j.amjcard.2011.07.045. Epub 2011 Sep 21.
There is uncertainty and debate regarding whether ischemic mitral regurgitation (MR) is a secondary epiphenomenon resulting from left ventricular (LV) dysfunction or confers an independent effect on exercise capacity and outcomes. We tested whether ischemic MR negatively affects exercise capacity and cardiovascular morbidity and mortality in patients with coronary artery disease (CAD) and those with inferior wall motion abnormality independent of LV dysfunction. Clinical follow-up over 5 years was obtained in 77 patients (64 ± 10 years old, LV ejection fraction 54 ± 11%) with at least mild ischemic MR from CAD and evidence of inferior wall motion abnormality who had exercise stress testing with perfusion imaging within 24 hours of echocardiography. Patients with active heart failure, ischemia, intrinsic valve disease, pulmonary and vascular diseases were excluded. Exercise capacity (METs, peak double product) was tested for relation to MR (vena contracta [VC] and jet area), LV size and function, and pulmonary pressures. Cox proportional hazards analysis assessed whether MR predicted cardiovascular events including hospitalization for heart failure, acute coronary syndrome, and myocardial infarction and cardiovascular and total mortalities. Univariate correlation identified MR with VC (r = -0.674, p <0.0001) and MR jet area (r = -0.575, p <0.0001) as determinants of decreased functional capacity evaluated by METs, with VC the stronger predictor. MR VC >2 mm (moderate ischemic MR) and age were independent predictors of cardiovascular events and death (hazard ratio 6.72 for MR, p = 0.04). In conclusion, in patients with CAD and LV inferior wall motion abnormality, MR negatively affects exercise capacity and is associated with increased cardiovascular morbidity and mortality. This effect appears independent of degree of LV dysfunction.
对于缺血性二尖瓣反流（MR）是否是左心室（LV）功能障碍的继发表现，或者对运动能力和预后是否有独立影响，目前仍存在不确定性和争议。我们检测了缺血性 MR 是否会对冠心病（CAD）患者和存在下壁运动异常且不伴有 LV 功能障碍的患者的运动能力和心血管发病率及死亡率产生负面影响。对 77 例（64 ± 10 岁，LV 射血分数 54 ± 11%）至少存在轻度缺血性 MR 的 CAD 患者和存在下壁运动异常的患者进行了 5 年的临床随访，这些患者在超声心动图检查后 24 小时内进行了运动负荷试验和灌注成像。排除了活动心衰、缺血、固有瓣膜疾病、肺和血管疾病的患者。对运动能力（METs、峰值双乘积）与 MR（收缩末期口宽度[VC]和射流面积）、LV 大小和功能以及肺压的关系进行了测试。Cox 比例风险分析评估了 MR 是否可预测心血管事件，包括因心衰、急性冠脉综合征和心肌梗死住院以及心血管和全因死亡率。单变量相关性分析确定 VC（r = -0.674，p <0.0001）和 MR 射流面积（r = -0.575，p <0.0001）与通过 METs 评估的运动能力下降有关，其中 VC 是更强的预测因子。MR VC >2mm（中度缺血性 MR）和年龄是心血管事件和死亡的独立预测因子（MR 的危险比为 6.72，p = 0.04）。结论，在 CAD 患者和 LV 下壁运动异常患者中，MR 会降低运动能力，与心血管发病率和死亡率增加相关。这种影响似乎与 LV 功能障碍的程度无关。
