中文摘要：

　目的：探讨终末期致心律不齐性右室型心肌病（ARVC）组织学特点和MRI特征。方法9例患者接受心脏移植，移植后离体心脏行组织病理学检查。7例移植前行MR扫描。结果：病理学检查显示所有心脏双室受累，右心室腔显著扩张7例，大致正常2例。右心室壁均显示严重透壁性肌肉丧失，其中3例几乎完全被脂肪组织替代，6例几乎完全被纤维脂肪组织替代。左心室中重度扩张8例、轻度扩张1例。左心室游离壁受累者7例，室间隔和左心室游离壁同时受累者2例。5例以脂肪细胞浸润为主伴小灶性纤维化；4例以弥漫性纤维化为主，伴灶性脂肪细胞浸润。7例MRI显示左心室射血分数平均（21．66±7．05）％，左心室轻度扩张3例，中度扩张2例，高度扩张2例。右心室腔明显扩大、壁薄者5例，其中3例可见线状高信号脂肪浸润；其余2例右心室形态、大小及信号均无明显异常，仅突出地表现为左心室受累。2例显示心外膜下脂肪信号浸润，选择性累及左心室，心尖和侧、后壁；3例左心室节段性变薄伴运动功能丧失分别累及室间隔、心尖和侧后壁；4例左心室游离壁变薄，厚度不足5mm。5例心肌灌注延迟显像均表现为不同程度的增强，左心室侧后壁强化者4例，其中透壁性和心外膜下各2例；室间隔肌壁间强化者2例；左心室心尖部强化者2例，灶性和透壁性各1例。4例患者右心室壁亦可见透壁性增强，其中累及右心室游离壁者2例，累及右心室心尖和后壁各1例。结论：ARVC合并左心室受累是该组患者的特点，MRI不仅能够准确地反映ARVC继发性的心室扩张及室壁运动的节段性变化，而且能检出心室壁的脂肪浸润以及纤维化等，因此能够在一定程度上反映生理状态下心脏组织学特征。

英文摘要：

Objective The aim of the present investigation was to confirm histopathology and MR features of arrhythmogenic right ventricular cardiomyopathy （ARVC）, particularly with the left ventricular involvement. Methods Nine patients （4 male, 5 female; 13 to 54 years old, mean age 40.44 ± 15.99）, with a pathologic diagnosis of ARVC at heart transplantation, were included, of which 7 patients were scanned for MR imaging before transplantation. Results Severe dilation of right ventricular （RV） cavity and left ventricular one （LV） were observed in 7 and 8 hearts, respectively. All hearts showed severe and transmural RV muscle loss, where RV wall was almost completely filled with either fatty tissue （3 cases） or fibrofatty tissue （6 cases）. LV involvement was diagnosed histologically in all cases. Both the septum and the LV free wall were affected in 2 cases; 7 cases disclosed selective free wall involvement. LV fatty or fibrofatty substitution was predominantly located in the subepicardial and mediomural wall layers in 5 hearts. a diffuse interstitial fibrosis with patchy infiltration was noted in the other 4 hearts. 7 patients underwent MR scanning. MR scanning demonstrated global RV severe dilation and thinning in 5 cases, of which linear fatty infiltration was found in 3 cases. RV presented wall thickness preservation and normal cavity in the remaining 2 cases, in which left involvement existed. LV was dilated in all cases （ mildly in 3, moderately in 2, severely in 2）. The LV ejection fraction was （21.66 ±7. 05） %, and subepicardial fatty infiltration was found in 2 patients, selectively involving posterolateral wall. 4 patients showed the LV wall thinning diffusely in free wall, and the other 3 mainly involved septum, apex and posterolateral wall, respectively. All 5 patients with delayed enhancement showed varying degrees of hyperenhancement, mainly involving the posterolateral wall （ transmural in 2 and epicardial in 2 ）, septum （ mediomural in 2 ） and apex in 2 （ focal or