摘要目的:对比扩张型心肌病（DCM）伴左心室过度小梁化患者与孤立DCM患者的心脏磁共振（CMR）特征差异，探究左心室过度小梁化对DCM患者预后的影响。方法:本研究为单中心回顾性队列研究，纳入2016年11月至2025年3月在北京协和医院就诊的DCM患者。收集患者基本临床资料及CMR数据，依据超声心动图结果将患者分为孤立DCM组和DCM伴左心室过度小梁化组。通过门诊或电话随访患者，以心血管死亡、心力衰竭住院及恶性心律失常事件（心室颤动、持续性室性心动过速）构成的复合终点作为结局事件。采用单因素和多因素Cox比例风险回归模型分析影响DCM患者预后的危险因素，生存分析采用Kaplan-Meier曲线，通过log-rank法比较2组患者结局事件发生率的差异。并根据左心室钆对比剂延迟增强（LGE）范围（≥7.5%和<7.5%）进行亚组分析。结果:共纳入114例DCM患者，孤立DCM组65例，DCM伴左心室过度小梁化组49例。孤立DCM组患者年龄（44±16）岁，男性44例（68%）；DCM伴左心室过度小梁化组患者年龄（40±17）岁，男性32例（65%）。超声心动图指标方面，孤立DCM组与DCM伴左心室过度小梁化组患者左心室射血分数［（34±8）%比（32±11）%］和左心室舒张末期内径［（65±8）mm比（66±8）mm］差异无统计学意义（ P均>0.05）。CMR特征方面，孤立DCM组的左心室舒张末容积［126（105，158）ml比146（114，185）ml］、左心室整体纵向应变［（-8.15±3.17）%比（-8.56±3.76）%］、左心室LGE范围［11.4（4.3，26.6）%比12.3（5.4，20.2）%］均低于DCM伴左心室过度小梁化组，而左心室射血分数则高于DCM伴左心室过度小梁化组［29（23，35）%比27（20，39）%］，但上述各项CMR指标在2组间的差异均无统计学意义（ P均>0.05）。预后方面，随访368（146，652）d，25例（22%）患者发生结局事件，其中心血管死亡4例（4%），心力衰竭住院22例（19%），恶性心律失常1例（1%）。Cox比例风险回归模型分析结果显示，左心室过度小梁化与DCM患者发生结局事件无关（ HR=0.682，95% CI 0.301~1.540， P=0.358），而左心室LGE范围与DCM患者预后相关（ HR=6.589，95% CI 1.064~40.794， P=0.043）。Kaplan-Meier曲线显示，孤立DCM组与DCM伴左心室过度小梁化组的累积结局事件发生率差异无统计学意义（log-rank P=0.355）；而左心室LGE范围≥7.5%的DCM患者的不良预后风险较左心室LGE范围<7.5%的患者高（log-rank P=0.032）。 结论:DCM伴左心室过度小梁化患者与孤立DCM患者的CMR特征无显著差异，左心室过度小梁化对DCM患者的预后亦无明显影响。而左心室LGE范围是影响DCM患者预后的危险因素。

abstractsObjective:To compare the differences in cardiac magnetic resonance (CMR) characteristics between dilated cardiomyopathy (DCM) patients accompanied by left ventricular hypertrabeculation and those with isolated DCM, and to investigate the impact of left ventricular hypertrabeculation on the prognosis of DCM patients.Methods:This single-center retrospective cohort study enrolled DCM patients who were admitted to Peking Union Medical College Hospital from November 2016 to March 2025. Basic clinical data and CMR parameters of the patients were collected. According to the results of echocardiography, the patients were divided into the isolated DCM group and the DCM with left ventricular hypertrabeculation group. Patients were followed up through outpatient visits or telephone calls. The composite endpoint consisting of cardiovascular death, heart failure hospitalization, and malignant arrhythmia events (ventricular fibrillation, sustained ventricular tachycardia) was used as the outcome event. Univariate and multivariate Cox proportional hazards regression models were used to analyze the risk factors affecting the prognosis of DCM patients. Survival analysis was performed using Kaplan-Meier curves, and the log-rank test was used to compare the differences in the incidence of outcome events between groups. Subgroup analysis was conducted according to the range of left ventricular late gadolinium enhancement (LGE) (≥7.5% and <7.5%).Results:A total of 114 DCM patients were enrolled, including 65 in the isolated DCM group and 49 in the DCM with left ventricular hypertrabeculation group. In the isolated DCM group, the patients had an age of (44±16) years, with 44 males (68%); in the DCM with left ventricular hypertrabeculation group, the patients had an age of (40±17) years, with 32 males (65%). Regarding echocardiographic parameters, there were no statistically significant differences in left ventricular ejection fraction ((34±8)% vs. (32±11)%) and left ventricular end-diastolic diameter ((65±8) mm vs. (66±8) mm) between the isolated DCM group and the DCM with left ventricular hypertrabeculation group (both P>0.05). In terms of CMR characteristics, the left ventricular end-diastolic volume (126 (105, 158) ml vs. 146 (114, 185) ml), left ventricular global longitudinal strain ((-8.15±3.17)% vs. (-8.56±3.76)%), and left ventricular LGE extent (11.4 (4.3, 26.6)% vs. 12.3 (5.4, 20.2)%) in the isolated DCM group were lower than those in the DCM with left ventricular hypertrabeculation group, while the left ventricular ejection fraction was higher than that in the DCM with left ventricular hypertrabeculation group (29 (23, 35)% vs. 27 (20, 39)%). However, there were no statistically significant differences in the above CMR parameters between the two groups (all P>0.05). For prognosis, during a follow-up of 368 (146, 652) days, 25 patients (22%) experienced outcome events, including 4 cases (4%) of cardiovascular death, 22 cases (19%) of heart failure hospitalization, and 1 case (1%) of malignant arrhythmia. Cox regression analysis showed that left ventricular hypertrabeculation was not associated with the occurrence of outcome events in DCM patients ( HR=0.682, 95% CI 0.301-1.540, P=0.358), while left ventricular LGE extent was associated with the prognosis of DCM patients ( HR=6.589, 95% CI 1.064-40.794, P=0.043). Kaplan-Meier curves showed that there was no statistically significant difference in the cumulative incidence of outcome events between the isolated DCM group and the DCM with left ventricular hypertrabeculation group (log-rank P=0.355); however, DCM patients with left ventricular LGE extent ≥7.5% had a higher risk of adverse prognosis than those with left ventricular LGE extent <7.5% (log-rank P=0.032). Conclusion:There are no significant differences in CMR characteristics between DCM patients with left ventricular hypertrabeculation and those with isolated DCM, and left ventricular hypertrabeculation had no impact on the prognosis of DCM patients. In contrast, left ventricular LGE extent was a risk factor affecting the prognosis of DCM patients.