Impact of Myocardial Scars on Left Ventricular Deformation in Type 2 Diabetes Mellitus After Myocardial Infarction by Contrast-Enhanced Cardiac Magnetic Resonance

Background Type 2 diabetes mellitus (T2DM) is a major risk factor for coronary artery disease and myocardial infarction (MI). The interaction of diabetic cardiomyopathy and MI scars on myocardial deformation in T2DM patients is unclear. Therefore, we aimed to evaluated myocardial deformation using cardiac magnetic resonance (CMR) in T2DM patients with previous MI and investigated the influence of MI on left ventricular (LV) deformationMethods Two hundred and two T2DM patients, including 46 with MI (T2DM(MI+)) and 156 without MI (T2DM(MI−)), and 59 normal controls who underwent CMR scans were included. Myocardial scars were assessed by late gadolinium enhancement. LV function and deformation, including LV global function index, LV global peak strain (PS), peak systolic strain rate (PSSR), and peak diastolic strain rate (PSDR), were compared among these groups. Correlation analysis and multivariate linear regression analyses were used to investigate the relationship between myocardial scars and LV deformation.Results There was a decrease in LV function and LV global PS, PSSR, and PDSR in the T2DM(MI+) group compared with those of the other groups. Furthermore, reduced LV deformation (p < 0.017) was observed in the T2DM(MI+) group with anterior wall infarction. The increased total LV infarct extent and infarct mass of LV were related to decreased LV global PS (radial, circumferential, and longitudinal directions; p < 0.01) and LV global PSSR (radial and circumferential directions, p < 0.02). Multivariate analysis demonstrated that NYHA functional class and total LV infarct extent were independently associated with LV global radial PS (β = −0.400 and β = −0.446, respectively, all p < 0.01; model R2 = 0.37) and circumferential PS (β = −0.339 and β = −0.530, respectively, all p < 0.01; model R2 = 0.41), while LV anterior wall infarction was independently associated with LV global longitudinal PS (β = −0.398, p = 0.006).Conclusions The myocardial scarring size in T2DM patients after MI is negatively correlated with LV global PS and PSSR, especially in the circumferential direction. Additionally, different MI regions have different effects on the reduction of LV deformation, and relevant clinical evaluations should be strengthened.

ST-segment resolution as a marker for severe myocardial fibrosis in ST-segment elevation myocardial infarction

Objective To investigate the relationship between ST-segment resolution (STR) and myocardial scar thickness after percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). Methods Forty-two STEMI patients with single-branch coronary artery stenosis or occlusion were enrolled. ST-segment elevations were measured at emergency admission and at 24 h after PCI. Late gadolinium-enhanced cardiac magnetic resonance imaging (CMR-LGE) was performed 7 days after PCI to evaluate myocardial scars. Statistical analyses were performed to assess the utility of STR to predict the development of transmural (> 75%) or non-transmural (< 75%) myocardial scars, according to previous study. Results The sensitivity and specificity of STR for predicting transmural scars were 96% and 88%, respectively, at an STR cut-off value of 40.15%. The area under the curve was 0.925. Multivariate logistic proportional hazards regression analysis disclosed that patients with STR < 40.15% had a 170.90-fold higher probability of developing transmural scars compared with patients with STR ≥ 40.15%. Pearson correlation and linear regression analyses showed STR percentage was significantly associated with myocardial scar thickness and size. Conclusion STR < 40.15% at 24 h after PCI may provide meaningful diagnostic information regarding the extent of myocardial scarification in STEMI patients.

ST-Segment Resolution As A Marker For Severe Myocardial Fibrosis in ST-Segment Elevation Myocardial Infarction

Objective To investigate the relationship between ST-segment resolution (STR) and myocardial scar thickness after percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). Methods Forty-two STEMI patients with single-branch coronary artery stenosis or occlusion were enrolled. ST-segment elevations were measured at emergency admission and at 24 h after PCI. Late gadolinium-enhanced cardiac magnetic resonance imaging (CMR-LGE) was performed 7 days after PCI to evaluate myocardial scars. Statistical analyses were performed to assess the utility of STR to predict the development of transmural (> 75%) or non-transmural (< 75%) myocardial scars, according to previous study. Results The sensitivity and specificity of STR for predicting transmural scars were 96% and 88%, respectively, at an STR cut-off value of 40.15%. The area under the curve was 0.92. Multivariate logistic proportional hazards regression analysis disclosed that patients with STR < 40.15% had a 112.95-fold higher probability of developing transmural scars compared with patients with STR ≥ 40.15%. STR percentage was negatively correlated with myocardial scar thickness (β=-0.838, P < 0.001) and size (β=-0.714, P < 0.001). Conclusion STR < 40.15% at 24 h after PCI may provide meaningful diagnostic information regarding the extent of myocardial scarification in STEMI patients.

ST-Segment Resolution as a Marker for Myocardial Scar in ST-Segment Elevation Myocardial Infarction

Objective: To investigate the relationship between ST-segment resolution (STR) and myocardial scar thickness after percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI).Methods: Forty-two STEMI patients with single-branch coronary artery stenosis or occlusion were enrolled. ST-segment elevations were measured at emergency admission and at 24 h after PCI. Late gadolinium-enhanced cardiac magnetic resonance imaging (CMR-LGE) was performed 7 days after PCI to evaluate myocardial scars. Statistical analyses were performed to assess the utility of STR to predict the development of transmural (>75%) or non-transmural (<75%) myocardial scars.Results: The sensitivity and specificity of STR for predicting transmural scars were 96% and 88%, respectively, at an STR cut-off value of 40.15%. The area under the curve was 0.92. Multivariate logistic proportional hazards regression analysis disclosed that patients with STR<40.15% had a 112.95-fold higher probability of developing transmural scars compared with patients with STR≥40.15%. STR percentage was negatively correlated with myocardial scar thickness (β=-0.838, P<0.001) and size (β=-0.714, P<0.001).Conclusion: STR<40.15% at 24 h after PCI may provide meaningful diagnostic nformation regarding the extent of myocardial scarification in STEMI patients.