Istituto di Ricerche Farmacologiche Mario Negri IRCCS.
Istituto di Ricerche Farmacologiche Mario Negri IRCCS;
J Vis Exp. 2022 Jul 12(185). doi: 10.3791/63888.
One of the main causes of out-of-hospital cardiac arrest is acute myocardial infarction (AMI). After successful resuscitation from cardiac arrest, approximately 70% of patients die before hospital discharge due to post-resuscitation myocardial and cerebral dysfunction. In experimental models, myocardial dysfunction after cardiac arrest, characterized by an impairment in both left ventricular (LV) systolic and diastolic function, has been described as reversible but very little data are available in cardiac arrest models associated with AMI in pigs. Transthoracic echocardiography is the first-line diagnostic test for the assessment of myocardial dysfunction, structural changes and/or AMI extension. In this pig model of ischemic cardiac arrest, echocardiography was done at baseline and 2-4 and 96 hours after resuscitation. In the acute phase, the examinations are done in anesthetized, mechanically ventilated pigs (weight 39.8 ± 0.6 kg) and ECG is recorded continuously. Mono- and bi-dimensional, Doppler and tissue Doppler recordings are acquired. Aortic and left atrium diameter, end-systolic and end-diastolic left ventricular wall thicknesses, end-diastolic and end-systolic diameters and shortening fraction (SF) are measured. Apical 2-, 3-, 4-, and 5-chamber views are acquired, LV volumes and ejection fraction are calculated. Segmental wall motion analysis is done to detect the localization and estimate the extent of myocardial infarction. Pulsed Wave Doppler echocardiography is used to record trans-mitral flow velocities from a 4-apical chamber view and trans-aortic flow from a 5-chamber view to calculate LV cardiac output (CO) and stroke volume (SV). Tissue Doppler Imaging (TDI) of LV lateral and septal mitral anulus is recorded (TDI septal and lateral s', e', a' velocities). All the recordings and measurements are done according to the recommendations of the American and European Societies of Echocardiography Guidelines.
心脏骤停患者的主要死亡原因之一是急性心肌梗死（AMI）。心脏骤停复苏成功后，约 70%的患者在出院前因心脏和大脑复苏后功能障碍而死亡。在实验模型中，心脏骤停后心肌功能障碍表现为左心室（LV）收缩和舒张功能均受损，这种功能障碍被描述为可逆转的，但在与猪 AMI 相关的心脏骤停模型中，几乎没有数据。经胸超声心动图是评估心肌功能障碍、结构变化和/或 AMI 扩展的一线诊断测试。在这种缺血性心脏骤停猪模型中，在复苏后 2-4 小时和 96 小时进行基线和超声心动图检查。在急性期，对麻醉、机械通气的猪（体重 39.8±0.6kg）进行检查，并连续记录心电图。采集单维和二维、多普勒和组织多普勒记录。测量主动脉和左心房直径、收缩末期和舒张末期左心室壁厚度、舒张末期和收缩末期直径以及缩短分数（SF）。采集心尖 2、3、4 和 5 腔视图，计算左心室容积和射血分数。进行节段性壁运动分析，以检测心肌梗死的定位和估计程度。脉冲波多普勒超声心动图用于从心尖 4 腔视图记录经二尖瓣血流速度和从心尖 5 腔视图记录经主动脉血流速度，以计算左心室心输出量（CO）和每搏输出量（SV）。记录左心室侧壁和间隔二尖瓣环状组织多普勒成像（TDI 间隔和侧壁 s'、e'、a'速度）。所有记录和测量均根据美国和欧洲超声心动图协会指南的建议进行。
