Assessment of Myocardial Dysfunction by Three-Dimensional Echocardiography Combined With Myocardial Contrast Echocardiography in Type 2 Diabetes Mellitus

Left ventricular systolic dyssynchrony: a novel imaging marker for early assessment of myocardial damage in Chinese type 2 diabetes mellitus patients with normal left ventricular ejection fraction and normal myocardial perfusion

OBJECTIVES

Myocardial damage is the important cause of heart failure (HF) in type 2 diabetes mellitus (T2DM), which is difficult to early diagnose, especially in T2DM with normal left ventricular ejection fraction (LVEF) and normal myocardial perfusion. The goal was to evaluate myocardial damage in T2DM with normal LVEF and normal myocardial perfusion by detecting left ventricular systolic dyssynchrony (LVSD), and find out the risk factors associated with LVSD.

METHODS

This study included 95 T2DM with normal LVEF, normal myocardial perfusion. 69 consecutive individuals without T2DM and CAD were enrolled as the control group with age-, sex- and BMI-matched. All participants underwent stress/rest 99mtechnetium-sestamibi (99mTc-MIBI) gated myocardial perfusion imaging (GMPI) and two-dimensional echocardiography within 1 week. Clinical data including age, gender, BMI, duration of diabetes, chronic diabetic complications, glycated haemoglobin A1c (HbA1c), fast blood glucose (FBG) and Brain Natriuretic Peptide (BNP) were collected from medical records. Left ventricular synchrony parameters were acquired, including phase standard deviation (PSD) and phase histogram bandwidth (PBW) by rest GMPI.

RESULTS

PSD and PBW in T2DM group were significantly higher than control group (P < .05). LVSD was detected in 20 (21%) T2DM patients. Compared to non-LVSD T2DM group, LVSD T2DM group had higher BMI, higher prevalence of BNP [Formula: see text] 35 pg/mL and chronic diabetic complications (P < .05). BNP [Formula: see text] 35 pg/mL had mild positive association with LVSD (r = 0.318, P = .004). In multivariate logistic regression, chronic diabetic complications and high BMI (> 23.4 kg/m2) were independent risk factors of LVSD (OR 5.64, 95% CI 1.58-20.16, P = .008; OR 6.77, 95% CI 1.59-28.89, P = .010).

CONCLUSIONS

LVSD existed in T2DM patients with normal LVEF and normal myocardial perfusion. Chronic diabetic complications and high BMI (> 23.4 kg/m2) were the independent risk factors of LVSD. LVSD based on GMPI can be the novel imaging marker to early assess myocardial damage in T2DM patients.

Predictive value of left ventricular dyssynchrony for short-term outcomes in three-vessel disease patients undergoing coronary artery bypass grafting with preserved or mildly reduced left ventricular ejection fraction

Background and objective

Coronary artery bypass grafting (CABG) is the reference standard intervention in coronary artery disease (CAD) patients with three-vessel disease (3VD). We aimed to evaluate the predictive value of left ventricular (LV) dyssynchrony for short-term adverse outcomes in patients with 3VD undergoing CABG with preserved or mildly reduced LV ejection fraction (LVEF).

Materials and methods

This study involved ninety-five 3VD patients with preserved or mildly reduced LVEF undergoing scheduled on-pump CABG. The pre-operative diameters and volumes of LV and LVEF were obtained by two-dimensional echocardiography. LV dyssynchrony parameters were acquired by real-time three-dimensional echocardiography (RT-3DE) and analyzed by HeartModel quantification software. And the perfusion index of LV was obtained by contrast echocardiography. The clinical endpoints of short-term adverse outcomes comprised 30-day mortality and/or composite outcomes of postoperative complications. Univariate and multivariate logistic regression analyses were used to identify risk factors for the occurrence of post-CABG short-term adverse outcomes.

Results

Short-term adverse outcomes occurred in 12 (12.6%) patients. These patients had higher LV dyssynchrony parameters obtained through RT-3DE. The standard deviation (SD) of the time to minimum systolic volume (Tmsv) corrected by heart rate over 16 segments (Tmsv16-SD%) [odds ratio (OR), 1.362; 95% confidence interval (CI) (1.090–1.702); P = 0.006], one of the LV dyssynchrony parameters, was independently associated with short-term adverse outcomes. Patients with poor synchronization tended to spend more time in the intensive care unit (ICU) and hospital after surgery.

Conclusion

Pre-operative LV dyssynchrony parameter Tmsv16-SD% obtained through RT-3DE could be a useful additional predictor of postoperative short-term adverse outcomes in 3VD patients with preserved or mildly reduced LVEF undergoing CABG.

Evaluation of right ventricular systolic and diastolic dysfunctions in patients with type 2 diabetes mellitus with poor glycemic control by layer specific global longitudinal strain and strain rate

BACKGROUND

In order to evaluate right ventricular (RV) systolic and diastolic dysfunctions in patients with type 2 diabetes mellitus (T2DM) with poor glycemic control by layer specific global longitudinal strain (GLS) and strain rate (GLSr).

METHODS

68 T2DM patients and 66 normal controls were enrolled for the present study. RV layer specific GLS (GLSEpi, GLSMid and GLSEndo represent the epimyocardial, middle layer and endomyocardial strains, respectively) and GLSr (GLSr-S, GLSr-E and GLSr-A represent the systole, early-diastole and late-diastole strain rate) were calculated by averaging each of the three regional peak systolic strains and strain rates along the entire RV free-wall (RVFW), entire RV free-wall and septal wall (RVFSW) on RV-focused view.

RESULTS

The absolute values of RV layer specific GLS (GLSEpi, GLSMid and GLSEndo) in RVFW in T2DM patients were significantly lower than normal controls (P < 0.01), while GLSr-A was significantly larger than normal controls (P < 0.001). The absolute values of RV layer specific GLS (GLSEpi and GLSMid) in RVFSW in T2DM patients were significantly lower than normal controls (P < 0.05), while GLSr-A was significantly larger than normal controls (P < 0.001). HbA1c were poor negatived correlated with GLSEpi in RVFW and RVFSW in T2DM patients (P < 0.05). ROC analysis showed that RV layer specific GLS and GLSr-A had a high diagnostic efficacy in T2DM patients, and GLSr-A in RVFSW have the best diagnostic value in RV diastolic function in T2DM patients (AUC: 0.773).

CONCLUSION

From the research, we found that layer specific GLS and GLSr could detect the RV myocardial dysfunctions and confirmed that the impaired RV systolic and diastole functions in T2DM patients with poor glycemic control. GLSr-A in RVFSW had the best diagnostic value in evaluating RV diastolic function in T2DM patients.