论文部分内容阅读
Aims: Late gadolinium enhancement (LGE) on contrast-enhanced magnetic resonance imaging (MRI) in hypertrophic cardiomyopathy (HCM) has been reported to be associated with myocardial fibrosis and cardiac events.In patients with HCM, speckle tracking echocardiography (STE) can identify subclinical global systolic dysfunction despite normal left ventricular (LV) chamber function.Our aim was to assess left ventricular twist mechanics and its relation to myocardial fibrosis in patients with HCM.Methods and results: Echocardiography and MRI were performed in 76 consecutive patients with HCM and normal chamber function.As controls, 46 age and sex-matched normal subjects were studied.For speckle tracking analysis of LV twist and rotation the dedicated software was used.The presence of myocardial fibrosis was detected byMRI.The patients were divided into fibrosis and non-fibrosis subgroups.Compared with the controls, the patients with HCM showed increased peak LV twist mainly because of increased apical rotation of those with myocardial fibrosis and LADs in patients with HCM were significantly higher than controls (P <0.001).The difference in LVEF between the two groups was not statistically significant (P>0.05).Myocardial fibrosis was detected in 49 (65.5%) patients with HCM.LVtwist, apical rotation, IVST, E/Em and LAVi in fibrosis subgroups were significantly higher than those in non-fibrosis subgroups (P<0.001), while basal rotation, LADs, LVEDd, and LVEF did not show significant differences between the two subgroups (P>0.05).LV twist was significantly correlated with LGE segments (r=0.785, P<0.001).The area under the ROC curve was 0.814 using LV twist to detect myocardial fibrosis (P <0.001, 95% confidence interval 0.625-0.890).The present study found that LV twist was significantly correlated with myocardial fibrosis segments.The area under the ROC curve was 0.814 using LV twist to detect myocardial fibrosis (95% confidence interval 0.625-0.890), which indicates that LV twist can sensitively and specifically reflect the degree of myocardial fibrosis in HCM patients.This result is consistent with the report by Saito et a1[22].The present study also showed that the cut-point of predicting myocardial fibrosis using LV twist was 18.22° , which provides a convenient and rapid quantitative parameter for clinical treatments and prognosis.Conclusion: LV twist and rotation in patients with HCM can be accurately measured using STE, These results suggest that LV twist might provide useful information on myocardial fibrosis and cardiac events in HCM patients with normal chamber function.