Department of Investigative Radiology, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan.
J Nucl Med. 2011 May;52(5):761-8. doi: 10.2967/jnumed.110.084848. Epub 2011 Apr 15.
A pig model of reduced left ventricular (LV) function and remodeling or chronic heart failure with long survival after myocardial infarction (MI) has not been established. The aim of this study was to evaluate the pathophysiologic status of a pig model of old MI using a series of PET studies.
Twenty-seven male farm pigs were divided into 2 groups: 7 animals in the control group and 20 animals that underwent a proximal coronary artery (CA) occlusion using an ameroid constrictor after distal CA ligation. A series of PET examinations was performed to assess LV volumes, LV functions, myocardial perfusion response to adenosine, and viability as water-perfusable tissue index.
The distal CA ligation inhibited arrhythmia during and after the operation, and a transmural anteroseptal MI, with an infarction area of 27% ± 5% of the whole left ventricle, was generated with a survival rate of 75% at 4 mo. Wall motion evaluated by (18)F-FDG PET was diffusely reduced, including the noninfarcted wall. Global LV ejection fraction as assessed by gated C(15)O PET was reduced (39% ± 16%) in the group undergoing occlusion, compared with the control group (66% ± 16%, P < 0.05). LV end-systolic (31.4 ± 9.2 cm(3)) and end-diastolic (52.7 ± 10.2 cm(3)) volumes were increased, compared with controls (15.2 ± 9.4 cm(3), P < 0.01, and 41.7 ± 11.5 cm(3), P < 0.05, respectively). Histology showed hypertrophy and development of microscopic fibrosis in noninfarcted myocardium. PET demonstrated the reduced myocardial perfusion response to adenosine and also reduced water-perfusable tissue index in remote segments.
The pig model of old MI generated by the chronic proximal CA obstruction after distal ligation was characterized by LV dysfunction and remodeling, with a high survival rate.
尚未建立左心室（LV）功能降低和重塑或慢性心力衰竭，以及心肌梗死（MI）后长期存活的猪模型。本研究的目的是使用一系列 PET 研究评估陈旧性 MI 猪模型的病理生理状态。
将 27 只雄性农场猪分为两组：对照组 7 只动物，用缩窄环经远端 CA 结扎后进行近端 CA 闭塞。进行一系列 PET 检查以评估 LV 容积、LV 功能、腺苷引起的心肌灌注反应和作为可水通透组织指数的存活能力。
远端 CA 结扎抑制了手术中和手术后的心律失常，并且产生了一个穿透性前间隔 MI，其梗塞面积为整个左心室的 27%±5%，在 4 个月时的存活率为 75%。用（18）F-FDG PET 评估的壁运动在非梗塞壁中均广泛减少。用门控 C（15）O PET 评估的整体 LV 射血分数在闭塞组中降低（39%±16%），与对照组（66%±16%，P<0.05）相比。LV 收缩末期（31.4±9.2cm3）和舒张末期（52.7±10.2cm3）容积增加，与对照组相比（15.2±9.4cm3，P<0.01，和 41.7±11.5cm3，P<0.05）。组织学显示非梗塞心肌中的肥大和微纤维化发展。PET 显示腺苷引起的心肌灌注反应降低，以及远程节段的可水通透组织指数降低。
通过远端结扎后慢性近端 CA 阻塞产生的陈旧性 MI 猪模型的特点是 LV 功能障碍和重塑，具有较高的存活率。
