Department of Cardiology, Liverpool Hospital, University of New South Wales, Sydney, Australia.
J Am Soc Echocardiogr. 2010 Dec;23(12):1251-8. doi: 10.1016/j.echo.2010.09.010.
Changes in left atrial (LA) volumes after ST elevation myocardial infarction are reported but have not been well described following non-ST elevation myocardial infarction (NSTEMI).
Seventy-five patients with NSTEMIs were studied within 48 hours of presentation and in follow-up at 6 and 12 months; they were compared with age-matched normal controls (n = 100). Biplane indexed LA volumes were measured, and phasic LA volumes (conduit, passive, and active emptying) were calculated. LA remodeling was defined as an increase in LA maximum volume over 12 months.
LA maximum volume was significantly larger at baseline in patients with NSTEMIs. At 12 months, maximum LA volume increased (27.6 ± 7.4 vs 30.2 ± 8.9 mL/m² P = .002), with LA remodeling present in 64% of the patients with NSTEMIs. LA passive emptying volume increased, with concurrent reductions in conduit and active emptying volumes. Although diabetes, major coronary artery disease, and a larger myocardial score were predictive of LA remodeling, E' velocity was the only independent predictor.
Patients with NSTEMIs had progressive LA enlargement with reductions in conduit and active emptying volumes, reflecting persistent left ventricular diastolic dysfunction consequent to coronary artery disease and associated diabetes. The measurement of LA volumes after NSTEMI may be useful to monitor chronic diastolic dysfunction resulting from ischemic burden.
ST 段抬高型心肌梗死（STEMI）后左心房（LA）容积的变化已有报道，但非 ST 段抬高型心肌梗死（NSTEMI）后的变化尚未得到很好的描述。
本研究共纳入 75 例 NSTEMI 患者，在发病后 48 小时内和 6 个月及 12 个月时进行研究，并与年龄匹配的正常对照组（n=100）进行比较。测量双平面指数化左心房容积，并计算左心房的时相容积（腔、被动和主动排空）。LA 重构定义为 12 个月时 LA 最大容积增加。
NSTEMI 患者的基线 LA 最大容积明显更大。在 12 个月时，最大 LA 容积增加（27.6±7.4 比 30.2±8.9 mL/m²，P=0.002），64%的 NSTEMI 患者存在 LA 重构。LA 被动排空容积增加，同时管腔和主动排空容积减少。尽管糖尿病、主要冠状动脉疾病和更大的心肌评分是 LA 重构的预测因素，但 E' 速度是唯一的独立预测因素。
NSTEMI 患者的 LA 逐渐增大，管腔和主动排空容积减少，反映了冠状动脉疾病和相关糖尿病导致的持续左心室舒张功能障碍。NSTEMI 后 LA 容积的测量可能有助于监测缺血负荷引起的慢性舒张功能障碍。
