Left and right ventricular systolic function impairment in type 1 diabetic young adults assessed by 2D speckle tracking echocardiography

Speckle-tracking echocardiography provides sensitive measurements of subtle early alterations associated with cardiac dysfunction in T2DM rats

BACKGROUND

Diabetic cardiomyopathy results in cardiac structural and functional abnormalities. Previous studies have demonstrated that inhibiting the RhoA/ROCK signalling pathway increases the injury resistance of cardiomyocytes. The early detection of cardiac structural and functional alterations may facilitate an improved understanding of the pathophysiologic progress and guide therapy. This study aimed to identify the optimal diagnostic measures for the subtle early alterations of cardiac dysfunction in type 2 diabetes mellitus (T2DM) rats.

METHODS

Twenty-four rat models were divided into four groups and received treatments for 4 weeks: the CON group (control rats), the DM group (T2DM rats), the DMF group (T2DM rats receiving fasudil) and the CONF group (control rats receiving fasudil) group. Left ventricular (LV) structure was quantified by histological staining and transmission electron microscopy. LV function and myocardial deformation were assessed by high-frequency echocardiography.

RESULTS

Treatment with fasudil, a ROCK inhibitor, significantly protected against diabetes-induced myocardial hypertrophy, fibrosis and mitochondrial dysfunction. Impaired LV performance was found in T2DM rats, as evidenced by significant reductions in the ejection fraction (EF), fractional shortening (FS) and the mitral valve (MV) E/A ratio (which decreased 26%, 34% and 20%, respectively). Fasudil failed to improve the conventional ultrasonic parameters in T2DM rats, but the myocardial deformation measured by speckle-tracking echocardiography (STE) were significantly improved (global circumferential strain, GCS: P = 0.003; GCS rate, GCSR: P = 0.021). When receiver operating characteristic (ROC) curves were used in combination with linear regression analysis, STE parameters were found to be characterized by both optimal prediction of cardiac damage [AUC (95% CI): fractional area change, FAC: 0.927 (0.744, 0.993); GCS: 0.819 (0.610, 0.945); GCSR: 0.899 (0.707, 0.984)] and stronger correlations with cardiac fibrosis (FAC: r = -0.825; GCS: r = 0.772; GCSR: r = 0.829) than conventional parameters.

CONCLUSION

The results suggest that STE parameters are more sensitive and specific than conventional parameters in predicting the subtle cardiac functional changes that occur in the early stage, providing new insight into the management of diabetic cardiomyopathy.

Subclinical systolic dysfunction detected by 2D speckle tracking echocardiography in adults with diabetes mellitus: systematic review and meta-analysis of 6668 individuals with diabetes mellitus and 7218 controls

PURPOSE

Speckle tracking echocardiography (STE) can help to identify subclinical features of diabetic cardiomyopathy (DCM). There is, however, significant heterogeneity in the reported strain values in literature. We performed a systematic review and meta-analysis to compare cardiac systolic strain values assessed by 2D-STE in asymptomatic adults with diabetes mellitus (DM) and healthy controls.

METHODS

Five databases were searched, and a total of 41 valid studies (6668 individuals with DM and 7218 controls) were included for analysis. Pooled mean in each group and mean difference (MD) for left ventricular global longitudinal strain (LVGLS), LV global circumferential strain (LVGCS), LV global radial strain (LVGRS), LV longitudinal systolic strain rate (LVSR), left atrial reservoir strain (LARS) and right ventricular GLS (RVGLS) were assessed.

RESULTS

Patients with DM had overall 2 units lower LVGLS than healthy subjects 17.5% [16.8, 18.3], vs 19.5 [18.7, 20.4], MD = - 1.96 [- 2.27, - 1.64]. Other strain values were also lower in patients with DM: LVGCS (MD = - 0.89 [- 1.26, - 0.51]); LVGRS (MD = - 5.03 [- 7.18, - 2.87]); LVSR (MD = - 0.06 [- 0.10, - 0.03]); LARS (MD = - 8.41 [- 11.5, - 5.33]); and RVGLS (MD = - 2.41 [- 3.60, - 1.22]). Meta-regression identified higher body mass index (BMI) as the single contributor to worse LVGLS, LVGCS and LVSR. Those with higher Hemoglobulin A1c had worse RVGLS.

CONCLUSION

Myocardial strains were reduced in whole heart in patients with DM. The largest reduction was observed in LA reservoir strain, followed by RVGLS and LVGLS. Higher BMI in patients with DM is associated with worse LV strain values.

Assessment of subclinical left ventricular systolic dysfunction in patients with type 2 diabetes: Relationship with HbA1c and microvascular complications

BACKGROUND

We aimed to examine the association between glycated hemoglobin (HbA1c), microvascular complications, and subclinical left ventricular (LV) systolic dysfunction, and to determine the strength of the correlation in asymptomatic patients with type 2 diabetes mellitus (T2DM).

METHODS

Global longitudinal strain (GLS) was employed to assess the subclinical LV function of 152 enrolled T2DM patients with preserved LV ejection fraction, with the cutoff for subclinical LV systolic dysfunction predefined as GLS < 18%.

RESULTS

According to univariate analysis, the reduced GLS exhibited association with the clinical features including HbA1c, triglyceride, systolic blood pressure, fasting glucose, heart rate, diabetic retinopathy, and urinary albumin creatinine ratio (UACR) (all p < .05). After the factors of gender, age, and related clinical covariables adjusted, multiple logistic regression analysis revealed the HbA1c (odds ratio [OR] 1.66; 95% confidence interval [CI] 1.30-2.13; p < .001), UACR (OR 2.48; 95% CI 1.12-5.47; p = .025) and triglyceride (OR 1.84; 95% CI 1.12-3.03; p = .017) as the independent risk factors for the reduced GLS. Receiver operating characteristic curve showed a predictive value of the HbA1c for the subclinical LV systolic dysfunction (area under curve: 0.74; p < .001).

CONCLUSIONS

In asymptomatic T2DM patients, subclinical LV systolic dysfunction was associated with HbA1c, diabetic complications, and triglyceride. More prominently, HbA1c may exert a prognostic significance for the progression of myocardial damage.

Role of Echocardiography in Diabetic Cardiomyopathy: From Mechanisms to Clinical Practice

It has been well established that diabetes mellitus (DM) is considered as a core risk factor for the development of cardiovascular diseases. However, what is less appreciated is the fact that DM may affect cardiac function irrespective of cardiac pathologies to which it contributes, such as coronary artery disease and hypertension. Although echocardiography provides accurate and reproducible diagnostic and prognostic data in patients with DM, its use in these patients is still underappreciated, resulting in progression of DM-related heart failure in many patients. Hence, in the present review, we aimed to discuss the role of echocardiography in the contemporary management of diabetic cardiomyopathy (DCM), as well as the role of emerging echocardiographic techniques, which may contribute to earlier diagnosis and more appropriate management of this complication of DM. In order to improve outcomes, focus must be placed on early diagnosis of this condition using a combination of echocardiography and emerging biomarkers, but perhaps the more important thing is to change perspective when it comes to the clinical importance of DCM.

Quality of glycemic control has significant impact on myocardial mechanics in type 1 diabetes mellitus

The potential associations between disease duration, glycemic control, and the echocardiographic markers of the myocardial mechanics were investigated in asymptomatic T1DM patients. Seventy T1DM patients (38.2 ± 11.7 years, 46 female) and 30 healthy volunteers were investigated. Besides the conventional and tissue Doppler measurements, left ventricular global longitudinal (GLS) and circumferential (GCS) strain as well as left and right atrial strain parameters were measured with 2D speckle tracking technique. Median HbA_1c level was 7.4 (1.8)%. Even when added age and hypertension to the model, current HbA1c level remained independent predictor of left ventricular GLS (p = 0.002), GCS (p < 0.001), mitral e' (p = 0.018), tricuspid e' (p = 0.018) and left (p = 0.039) and right atrial conduit strain (p = 0.047) in multiple linear regression models. Correlations between disease duration and the echocardiographic variables lost their significance in multiple models. In patients with a combination of HbA_1c ≤ 7.4% and no hypertension, echocardiographic findings did not differ from those in healthy volunteers. Patients with HbA_1c > 7.4% and no hypertension and especially patients with coexisting hypertension and HbA_1c > 7.4%, exhibited significantly impaired myocardial mechanics. Quality of glycemic control has a significant impact on myocardial mechanics in T1DM patients. Regarding disease duration this relationship was not proved.

Highlighting the Role of Obesity and Insulin Resistance in Type 1 Diabetes and Its Associated Cardiometabolic Complications

PURPOSE OF REVIEW

This narrative review appraises research data on the potentially harmful effect of obesity and insulin resistance (IR) co-existence with type 1 diabetes mellitus (T1DM)-related cardiovascular (CVD) complications and evaluates possible therapeutic options.

RECENT FINDINGS

Obesity and IR have increasingly been emerging in patients with T1DM. Genetic, epigenetic factors, and subcutaneous insulin administration are implicated in the pathogenesis of this coexistence. Accumulating evidence implies that the concomitant presence of obesity and IR is an independent predictor of worse CVD outcomes. The prevalence of obesity and IR has increased in patients with T1DM. This increase can be partly attributed to general population trends but, additionally, to iatrogenic weight gain caused by insulin treatment. This association might be the missing link explaining the excess CVD burden observed in patients with T1DM despite optimal glycemic control. Data on newer agents for type 2 diabetes mellitus (T2DM) treatment are unraveling novel ways to challenge this aggravating coexistence.

Evaluation of the left ventricular systolic function and myocardial deformation by real-time three-dimensional (four-dimensional) and speckle-tracking echocardiography in children with type 1 diabetes mellitus

AIM

This study aimed to evaluate the role of real-time three-dimensional (known as four-dimensional) echocardiography and three-dimensional speckle-tracking echocardiography for the early detection of left ventricular systolic dysfunction in asymptomatic children with type 1 diabetes mellitus.

MATERIALS AND METHOD

This cross-sectional study included 38 patients (mean age 15.4 ± 2.9, 42.1% male) and 38 age, gender, and body measurements matched healthy children. Each patient underwent an interview about medical history, a detailed clinical examination, blood laboratory tests, conventional echocardiography, and tissue Doppler imaging. Left ventricular ejection fraction; global longitudinal, circumferential, radial strain; twist; and torsion were measured by real-time three-dimensional and speckle-tracking echocardiography.

RESULTS

Conventional echocardiography and tissue Doppler imaging showed normal left ventricular systolic function in the patients. Although left ventricular ejection fraction (61.6 ± 1.4%, 61.8 ± 1.1%, p = 0.386), global longitudinal [-26.6 (-27.7 to -26.1)%, -26.2 (-27.7 to -24.9)%, p = 0.224], and radial strain [44.4 (42.4-45.9)%, 43.9 (41-46.1)%, p = 0.513] were similar to the controls, circumferential strain (-27.3 ± 1.3%, -28.0 ± 1.6%, p = 0.048) and twist (9.5 ± 2.3°, 11.4 ± 3.0°, p = 0.003) were decreased in the patients compared with controls.

CONCLUSION

We found that even in children with asymptomatic type 1 diabetes mellitus with normal left ventricular ejection fraction, circumferential function was impaired and rotation pattern was changed. This novel echocardiographic method might be an important tool for detecting left ventricular systolic dysfunction in type 1 diabetes mellitus children before it becomes overt on conventional echocardiography and tissue Doppler imaging.

Diabetic cardiomyopathy: Clinical phenotype and practice

Diabetic cardiomyopathy (DCM) is a pathophysiological condition of cardiac structure and function changes in diabetic patients without coronary artery disease, hypertension, and other types of heart diseases. DCM is not uncommon in people with diabetes, which increases the risk of heart failure. However, the treatment is scarce, and the prognosis is poor. Since 1972, one clinical study after another on DCM has been conducted. However, the complex phenotype of DCM still has not been fully revealed. This dilemma hinders the pace of understanding the essence of DCM and makes it difficult to carry out penetrating clinical or basic research. This review summarizes the literature on DCM over the last 40 years and discusses the overall perspective of DCM, phase of progression, potential clinical indicators, diagnostic and screening criteria, and related randomized controlled trials to understand DCM better.

Echocardiographic evaluation in type 1 diabetes mellitus

INTRODUCTION

Type 1 diabetes (T1D) is a chronic disease with peak incidence in adolescence; it has a major impact on morbidity and mortality, especially cardiovascular. Diabetic cardiomyopathy is characterized by structural and functional lesions in the absence of other diseases and is involved in the progression to heart failure. Echocardiography has led to the identification of early cardiac lesions, despite controversial results in the literature in patients with T1D.

OBJECTIVE

The objective of this study is to assess cardiac changes in individuals with TD1 compared to the control group using conventional two-dimensional Doppler and advanced speckle tracking echocardiography.

METHODS

This is a case-control study with 40 asymptomatic, normotensive T1D patients aged 20 to 50 years and 40 healthy subjects. Two-dimensional echocardiography was performed to measure myocardial thickness and cardiac chambers. Tissue Doppler echocardiography was used for diastolic analysis and speckle tracking echocardiography to quantify ventricular systolic function.

RESULTS

The mean age was 33 years in both groups, with an average T1D duration of 18 years; 20% of patients with T1D had diabetic retinopathy; 12.5% kidney injury; and 10% peripheral neuropathy. There were differences in the left ventricular diastolic function parameters (lateral E', middle E' and S/D ratio) and right ventricle (tricuspid E and tricuspid E'/A' ratio). The mean value of the global longitudinal strain was -21.7% (+- 2.3) in the T1D group and -21.0% (+-2.0) in the control group (p=0.21).

CONCLUSION

Echocardiography revealed a reduction in indices of diastolic function in T1D compared to the control group, which may be the initial cardiac lesion in diabetes.

The use of echocardiography in type 1 diabetes

INTRODUCTION

Type 1 diabetes (T1D) is a chronic disease with peak incidence in adolescence; it has a major impact on morbidity and mortality, especially cardiovascular. Diabetic cardiomyopathy is characterized by structural and functional lesions in the absence of other diseases and is involved in the progression to heart failure. Echocardiography has led to the identification of early cardiac lesions, despite controversial results in the literature in patients with T1D.

OBJECTIVE

The objective of this study is to assess cardiac changes in individuals with TD1 compared to the control group using conventional two-dimensional Doppler and advanced speckle tracking echocardiography.

METHODS

This is a case-control study with 40 asymptomatic, normotensive T1D patients aged 20 to 50 years and 40 healthy subjects. Two-dimensional echocardiography was performed to measure myocardial thickness and cardiac chambers. Tissue Doppler echocardiography was used for diastolic analysis and speckle tracking echocardiography to quantify ventricular systolic function.

RESULTS

The mean age was 33 years in both groups, with an average T1D duration of 18 years; 20% of patients with T1D had diabetic retinopathy; 12.5% kidney injury; and 10% peripheral neuropathy. There were differences in the left ventricular diastolic function parameters (lateral E', middle E' and S/D ratio) and right ventricle (tricuspid E and tricuspid E'/A' ratio). The mean value of the global longitudinal strain was -21.7% (+- 2.3) in the T1D group and -21.0% (+-2.0) in the control group (p=0.21).

CONCLUSION

Echocardiography revealed a reduction in indices of diastolic function in T1D compared to the control group, which may be the initial cardiac lesion in diabetes.

Early left ventricular systolic dysfunction in asymptomatic patients with type 1 diabetes: a single-center, pilot study

AIMS

Prevalence and risk factors of pre-symptomatic left ventricular systolic dysfunction (LVSD) in individuals with type 1 diabetes (T1D) have not been adequately studied. The present cross-sectional study assessed the prevalence of early LVSD in asymptomatic patients with type 1 diabetes and investigated potential risk factors.

METHODS

Consecutive patients with T1D, free of cardiovascular disease and significant evident microvascular complications were examined. LVSD was assessed by speckle-tracking echocardiography and calculation of global longitudinal strain (GLS). Abnormal GLS was defined as a value>-18.7%. We looked for possible associations between the presence of LVSD and patient demographic, clinical and laboratory characteristics, as well as with autonomic nervous system (ANS) function and arterial stiffness.

RESULTS

We enrolled 155 T1D patients (29.7% men, age 36.7 ± 13.1 years, diabetes duration 19.1 ± 10.0 years, HbA1c 7.5 ± 1.4% [58 ± 15 mmol/mol]). Early LVSD was prevalent in 53 (34.2%) patients. Multivariable analysis identified male gender (OR:4.14; 95% CI:1.39-12.31, p = 0.011), HbA1c (OR:1.59 per 1% increase; 95% CI:1.11-2.28, p = 0.011), glomerular filtration rate (GFR, OR:0.97; 95% CI:0.95-0.99, p = 0.010) and BMI (OR:1.19; 95% CI:1.06-1.34, p = 0.003) as independent predictors of LVSD presence.

CONCLUSIONS

Early subclinical LVSD is a common finding in asymptomatic patients with T1D, free of macrovascular and significant microvascular complications. Apart from chronic hyperglycemia, increased adiposity may be implicated in its etiology. Further investigation is warranted to identify patients at high risk for whom early screening is required and to determine possible associations between risk markers identified in the present analysis and long-term outcomes.

Assessment of subclinical diabetic cardiomyopathy by speckle-tracking imaging

BACKGROUND

Diastolic dysfunction is traditionally believed to be the first subclinical manifestation of diabetic cardiomyopathy (DCM), leading to systolic dysfunction and then overt heart failure. However, in the last few years, several studies suggested that systolic subclinical dysfunction measured by speckle-tracking echocardiography (STE) may appear ahead of diastolic dysfunction. In this review, the main endpoint is to show whether subclinical myocardial systolic dysfunction appears ahead of diastolic dysfunction and the implication this may have on the evolution and management of DCM.

MATERIALS AND METHODS

We performed a search in PubMed for all relevant publications on the assessment of DCM by STE from 1 June 2015 to 1 June 2020.

RESULTS AND CONCLUSIONS

The results illustrate that subclinical systolic dysfunction assessed by STE is present in early DCM stages, with or without the association of diastolic dysfunction. This could be a promising perspective for the early management of patients with DCM leading to the prevention of the overt form of disease.

Cardiovascular disease in young People with Type 1 Diabetes: Search for Cardiovascular Biomarkers

Premature onset of cardiovascular disease is common in people with type 1 diabetes and is relatively understudied in youth. Several reports in adolescents and young adults with diabetes demonstrate evidence of arterial stiffness and cardiac dysfunction, yet critical gaps exist in our current understanding of the temporal progression of cardiac and vascular dysfunction in these youth, and mechanistic investigations with robust pathophysiologic assessment are lacking. This review attempts to summarize relevant cardiovascular studies concerning children, adolescents, and young adults with type 1 diabetes. We focus on imaging-based biomarkers routinely applied to youth and adults that are well-established in their ability to predict adjudicated cardiovascular outcomes, and their relevant physiologic interpretation. Particularly, we focus the attention to 1) cardiac ventricular strain imaging techniques which are known to be predictive of clinical outcomes in patients with heterogenous causes of heart failure, and 2) stiffness in large arteries, a well-established prognostic marker of cardiovascular events. We conclude that there remains an urgent need for sensitive and quantitative biomarkers to define the natural history of cardiac and vascular disease origination and progression in type 1 diabetes, and set the stage for interpreting interventional studies focused on preventing, reversing or slowing disease progression.

Associations of (pre)diabetes with right ventricular and atrial structure and function: the Maastricht Study

Backgrounds

The role of right ventricular (RV) and atrial (RA) structure and function, in the increased heart failure risk in (pre)diabetes is incompletely understood. The purpose of this study is to investigate the associations between (pre)diabetes and RV and RA structure and function, and whether these are mediated by left ventricular (LV) alterations or pulmonary pressure.

Methods

Participants of the Maastricht Study; a population-based cohort study (426 normal glucose metabolism (NGM), 142 prediabetes, 224 diabetes), underwent two-dimensional and tissue Doppler echocardiography. Multiple linear regression analyses with pairwise comparisons of (pre)diabetes versus NGM, adjusted for cardiovascular risk factors, and mediation analyses were used.

Results

In general, differences were small. Nevertheless, in individuals with prediabetes and diabetes compared to NGM; RA volume index was lower (both p < 0.01, p_trend < 0.01), RV diameter was lower (both p < 0.01, p_trend < 0.01) and RV length was significantly smaller in diabetes (p = 0.67 and p = 0.03 respectively, p_trend = 0.04), TDI S′RV was lower (p = 0.08 and p < 0.01 respectively, p_trend < 0.01), TDI E′RV was lower (p = 0.01 and p = 0.02 respectively, p_trend = 0.01) and TDI A′RV was lower (p < 0.01 and p = 0.07 respectively, p_trend = 0.04). Only the differences in RA volume index (7.8%) and RV diameter (6.2%) were mediated by the maximum tricuspid gradient, but no other LV structure and function measurements.

Conclusions

(Pre)diabetes is associated with structural RA and RV changes, and impaired RV systolic and diastolic function, independent of cardiovascular risk factors. These associations were largely not mediated by indices of LV structure, LV function or pulmonary pressure. This suggests that (pre)diabetes affects RA and RV structure and function due to direct myocardial involvement.

Abnormal left ventricular global strain during exercise-test in young healthy smokers

Background. It is unknown how much precociously the cigarette smoking (CS) may compromise the integrity of the cardiovascular (CV) system. Myocardial function can be routinely assessed by conventional echocardiography, but abnormalities are only detected when somewhat a remodelling has already occurred. These limitations could be overcome by strain imaging. Methods. We evaluated whether young smokers with normal left ventricular (LV) geometry, wall motion and ejection fraction may present abnormalities in myocardial deformation, both at rest and during physical effort. We selected 50 young smokers with no additional CV risk factors, and 60 non-smokers to undergo a standardized exercise-test. Consistently, we evaluated the CV adaptation to exercise by both conventional echocardiography and speckle-tracking analysis (2D-STE). Results. We found no difference between smokers and controls regarding baseline characteristics; as expected, smokers presented with lower HDL-cholesterol (p < 0.005), and higher fibrinogen, C-reactive protein (CRP), and interleukin-6 (p < 0.001). Conventional echocardiography parameters were not different between groups, while we detected a different behaviour of global longitudinal strain (GLS), global circumferential strain (GCS) and twist by 2D-STE during exercise-test. Indeed, GLS, GCS and twist behaved differently during exercise test in smokers with respect to controls. We found an association between CS, inflammation and LV mechanics changes uncovered by physical effort, and regression analysis confirmed that the intensity of the exposure to cigarette smoking, together with the inflammatory status (CRP, fibrinogen and Il-6) plasma levels, drive this impairment. Conclusions. We confirm strain imaging (2D-STE) as a very useful tool to identify early changes in cardiac mechanics, as adaptation to exercise; our findings may reflect a very precocious functional abnormality in active smokers, likely long before structural damage occurs.

Speckle-tracking echocardiography combined with imaging mass spectrometry assesses region-dependent alterations

Left ventricular (LV) contraction is characterized by shortening and thickening of longitudinal and circumferential fibres. To date, it is poorly understood how LV deformation is altered in the pathogenesis of streptozotocin (STZ)-induced type 1 diabetes mellitus-associated diabetic cardiomyopathy and how this is associated with changes in cardiac structural composition. To gain further insights in these LV alterations, eight-week-old C57BL6/j mice were intraperitoneally injected with 50 mg/kg body weight STZ during 5 consecutive days. Six, 9, and 12 weeks (w) post injections, echocardiographic analysis was performed using a Vevo 3100 device coupled to a 30-MHz linear-frequency transducer. Speckle-tracking echocardiography (STE) demonstrated impaired global longitudinal peak strain (GLS) in STZ versus control mice at all time points. 9w STZ animals displayed an impaired global circumferential peak strain (GCS) versus 6w and 12w STZ mice. They further exhibited decreased myocardial deformation behaviour of the anterior and posterior base versus controls, which was paralleled with an elevated collagen I/III protein ratio. Additionally, hypothesis-free proteome analysis by imaging mass spectrometry (IMS) identified regional- and time-dependent changes of proteins affecting sarcomere mechanics between STZ and control mice. In conclusion, STZ-induced diabetic cardiomyopathy changes global cardiac deformation associated with alterations in cardiac sarcomere proteins.

Reduced Exercise Capacity in Diabetes Mellitus Is Not Associated with Impaired Deformation or Twist

BACKGROUND

Exercise capacity is frequently reduced in people with diabetes mellitus (DM) and may be due to subclinical cardiac dysfunction. Speckle-tracking echocardiography is now widely available; however, the clinical utility and significance of left ventricular (LV) strain and twist parameters remain uncertain. We hypothesized that LV strain and twist would be reduced in DM subjects during exercise.

METHODS

Adults with type 1 or type 2 DM and age- and sex-matched controls performed cardiopulmonary exercise testing (VO₂ peak) and supine bicycle exercise echocardiography. Detailed echocardiographic assessment of biventricular function was performed at baseline and repeated during incremental exercise to maximal intensity.

RESULTS

Of the 60 participants completing the study protocol, 51 (34 DM, 17 controls; mean age, 42 ± 13 years; 69% male; DM duration, 16 ± 10 years) had sufficient image quality to assess LV deformation and twist mechanics at rest. Of these, 38 (25 DM, 13 controls) were able to be assessed immediately after exercise. Baseline LV systolic and diastolic function using standard echocardiography measurements were similar between groups. Resting LV global longitudinal strain, twist, twist rate and untwist rate, and the corresponding peak exercise and reserve measures did not differ significantly. As compared with the control subjects, exercise capacity was reduced in the DM cohort (VO₂ peak 33 ± 10 vs 41 ± 12 mL/minute/kg; P = .02); however, no correlation was observed between VO₂ peak and LV twist reserve (R = 0.28, P = .09), LV twist rate reserve (R = 0.14, P = .39), or LV untwist rate reserve (R = 0.24, P = .14).

CONCLUSIONS

Despite reduced VO₂ peak, LV twist mechanics at rest and after maximal intensity exercise did not differ significantly in a cohort of asymptomatic DM subjects with normal resting LV systolic and diastolic function compared with age- and sex-matched controls. This would suggest that exercise capacity can be reduced in the absence of subclinical cardiac dysfunction and that noncardiac factors should be considered as alternative explanations.

Left ventricular functions in pediatric patients with ten years or more type 1 diabetes mellitus: Conventional echocardiography, tissue Doppler, and two-dimensional speckle tracking study

BACKGROUND

Cardiac dysfunction is a complication of type 1 diabetes mellitus (T1DM) with primary concern in adults. However, studies have evaluated left ventricle (LV) myocardial changes in pediatrics but not the long-term effect of T1DM in such vulnerable age. Therefore, we assessed LV functions in pediatric patients with long-duration T1DM using different echocardiographic modalities.

METHODS

Between July 2015 and March 2016, 48 T1DM patients were prospectively compared to 35 healthy controls. Pediatric patients with T1DM for 10 years or more were included in the study. Patients were subjected to history taking, clinical examination, glycated hemoglobin (HbA1c), and microalbuminuria measurements. Moreover, conventional echocardiography, tissue Doppler, and 2D speckle tracking were performed to analyze LV functions.

RESULTS

Mean age of patients was 15.5 ± 2 years, and mean T1DM duration was 11.7 ± 1.8 years. LV dimensions, EF and FS, and mass index did not statistically differ between groups, but E/E' ratio was significantly higher in the diabetic group. Global longitudinal strain (GLS) and global circumferential strain (GCS) were significantly lower in diabetic patients compared with controls (P = 0.038; P = 0.001, respectively). Mean HbA1c was found to be a significant predictor of decreased GLS in the diabetic population (95% CI, 0.096-0.244; P = 0.001) but not predicting GCS. Microalbuminuria had no significance in predicting strain.

CONCLUSIONS

Despite the long-duration of affection with T1DM during childhood in our patients, alterations on LV myocardial function could not be detected either clinically or by conventional echocardiography. Tissue Doppler and speckle tracking could be used in the follow up of myocardial status in pediatric diabetic patients.

Predictors of early cardiac changes in patients with type 1 diabetes mellitus: An echocardiography-based study

In patients with type 1 diabetes mellitus (T1DM) imaging studies have demonstrated an increased prevalence of left ventricular diastolic dysfunction and increased left ventricular mass (LVM) unrelated to arterial hypertension and ischemic heart disease. The aim of our study was to identify potential predictors of early subclinical changes in cardiac chamber size and function in such patients. Sixty-one middle-aged asymptomatic normotensive patients with T1DM were included in the study. Conventional and tissue Doppler echocardiography was performed and fasting serum levels of glucose, glycated hemoglobin (HbA1c), lipids, and creatinine were measured. We found moderate bivariate correlations of body mass index (BMI) with left atrial volume (r = 0.47, p < 0.01), LVM (r = 0.42, p < 0.01), left ventricular relative wall thickness (r = 0.32, p = 0.01), and all observed parameters of diastolic function of both ventricles. The five-year average value of HbA1c weakly correlated with the Doppler index of left ventricular filling pressure E/e´sept (r = 0.27, p = 0.04). We found no significant association of diabetes duration, five-year trend of HbA1c, serum lipids, and glomerular filtration rate with cardiac structure and function. After adjusting for other parameters, BMI remained significantly associated with left atrial volume, LVM as well as with the transmitral Doppler ratio E/A. In our study, BMI was the only observed parameter significantly associated with subclinical structural and functional cardiac changes in the asymptomatic middle-aged patients with T1DM.

Impact of acute hyperglycemia on layer-specific left ventricular strain in asymptomatic diabetic patients: an analysis based on two-dimensional speckle tracking echocardiography

BACKGROUND

Hyperglycemia has detrimental effect on ischemic myocardium, but the impact of acute hyperglycemia on the myocardium in asymptomatic diabetic patients has not been fully elucidated. Thus, this follow-up study was aimed to investigate the effects and reversibility of acute hyperglycemia on regional contractile function of left ventricle (LV) in diabetic patients without cardiovascular disease.

METHODS

The two-dimensional speckle tracking echocardiography (2D-STE), including multilayer strain analysis, was used for evaluation of global and regional LV function in asymptomatic, normotensive patients with uncomplicated diabetes, with acute hyperglycemia ( ≥ 11.1 mmol/l) (Group A, n = 67), or with optimal metabolic control (fasting plasma glucose < 7 mmol/l and HbA1c < 7%) (Group B, n = 20), while 20 healthy individuals served as controls (Group C). In group A, after 72 h of i.v. continuous insulin treatment (at the time euglycemia was achieved) (second examination) and after 3 months following acute hyperglycemia (third examination) 2D-STE was repeated.

RESULTS

Global longitudinal strain (GLS) (- 19.6 ± 0.4%) in Group A was significantly lower in comparison to both groups B (- 21.3 ± 0.4%; p < 0.05) and C (- 21.9 ± 0.4%; p < 0.01) at baseline, while we could not detect the differences between groups B and C. Peak systolic longitudinal endocardial (Endo), mid-myocardial (Mid) and epicardial (Epi) layer strain were significantly lower in group A at baseline compared to both groups B and C. Deterioration in peak systolic circumferential strain was observed at basal LV level, in all three layers (Endo, Mid and Epi) and in mid-cavity LV level in Epi layer in group A in comparison to group C. Moreover, in group A, after euglycemia was achieved (at second and third examination) GLS, as well as peak longitudinal and circumferential strain remain the same.

CONCLUSION

Acute hyperglycemia in asymptomatic diabetic patients has significant negative effects on systolic LV myocardial mechanics primarily by reducing GLS and multilayer peak systolic longitudinal and circumferential strain which was not reversible after three months of good glycemic control.

Impairment of left and right ventricular longitudinal strain in asymptomatic children with type 1 diabetes

Aim

The relationship between type 1 diabetes (T1DM) and cardiac function in children is not well established. The purpose of this study was to investigate whether children and adolescents with T1DM present early asymptomatic abnormalities of left ventricular (LV) and right ventricular (RV) function. In addition, we evaluated the relationship of any such abnormalities with glycemic control and diabetes duration.

Methods

This was a prospective study. Standard echocardiography, tissue Doppler imaging, and two-dimensional strain analysis were performed prospectively in 52 children with T1DM. The results were compared with those from 52 healthy children matched for age and sex.

Results

There were no significant differences between the two groups in LV ejection fraction or RV systolic function. There was a difference between the two study groups in transtricuspid flow: the E-wave and A-wave velocities were significantly higher in the diabetic group. Left ventricular global longitudinal strain (LV GLS) was significantly lower in children with T1DM (−20.01 ± 1.86% vs. −22.99 ± 0.98%, respectively; P < .001), as was RV free-wall longitudinal strain (RV FWLS) (−29.13 ± 1.85% vs. −30.22 ± 1.53%, respectively; P = .002). LV GLS was correlated with diabetes duration (r = 0.444, P < .001) and glycated hemoglobin (HbA1c) (r = 0.683, P < .001); however, no correlation was found between RV FWLS and HbA1c or diabetes duration.

Conclusions

Our findings suggest that LV GLS and RV FWLS are impaired in children with T1DM and that the decrease in LV GLS is correlated with diabetes duration and HbA1c levels.

Diabetic cardiomyopathy: acute and reversible left ventricular systolic dysfunction due to cardiotoxicity of hyperglycaemic hyperosmolar state-a case report†

Background

Diabetic cardiomyopathy (DC) is defined as a ventricular diastolic and/or systolic dysfunction, which is directly related to diabetes mellitus (DM) in the absence of coronary artery disease, valvular, congenital or hypertensive heart disease, and alcoholism. In this report, we present an unusual case of a patient with DC and reversible, acute left ventricular systolic dysfunction due to cardiotoxicity of hyperosmolar hyperglycaemic state (HHS).

Case summary

A 20-year-old male patient presented with weakness and polyuria. Physical examination and electrocardiogram were normal. Laboratory results and arterial blood gas analysis were consistent with HHS. Baseline echocardiography showed global left ventricular hypokinesis with an ejection fraction (EF) of 36%. The patient’s clinical condition improved after blood glucose level normalization and echocardiography revealed progressive improvement in the left ventricular systolic function with an EF of 54% at the 5-day follow-up and an EF of 69% at the 15-day follow-up.

Discussion

Uncontrolled DM and hyperglycaemic crisis may result in cardiotoxicity, acute left ventricular systolic dysfunction, and DC. The pathophysiological mechanism of this phenomenon is still unclear. Blood glucose control is the most important strategy for the prevention of DC.

The Significance of Right Ventricle in Young Subjects with Diabetes Mellitus Type 1. An echocardiographyic study

BACKGROUND

Diabetes mellitus type 1 (DM1) is associated with high risk for cardiovascular disease and early detection of myocardial dysfunction is very important for the prevention of cardiac complications. Although the functionality of right ventricule is important in a lot of disease affecting long time prognosis and progression, in diabetic type 1 patients has not been studied in depth yet.

OBJECTIVES

To evaluate the right ventricular function by using both conventional echocardiography as well as speckle tracking echocardiography (STE) in young adults with diabetes mellitus type 1.

METHODS

We included 60 young asymptomatic adults diagnosed with diabetes mellitus type 1 (mean interval from diagnosis 9±6 years) and 90 healthy controls. Conventional and STE Echocardiography was acquired using the GE Vivid S60 equipment. The longitudinal right ventricular strain 6 segments (RV GLS global) and 3 segments (RVFW GLS) of right ventricle (RV GLSbazal, RV GLSmid, RV GLSapex) as well were obtained using the EchoPAC BT13 workstation.

RESULTS

No significant intergroup differences in EF were noted. Conventional echocardiographic parameters revealed lower tricuspid annular velocities Et, At and Et/At ratio compared to controls suggesting a diastolic disfunction in diabetes group. RV speckle tracking strain measurements showed no significant difference between the groups.

CONCLUSIONS

Young adults with type 1 diabetes mellitus and without known heart disease have diastolic right ventricular dysfunction. The subclinical myocardial systolic function is preserved in early stages.

Quantification of fetal myocardial function in pregnant women with diabetic diseases and in normal controls using speckle tracking echocardiography (STE)

Background The purpose of our study was to quantify the fetal myocardial function in pregnant women with diabetic diseases (FDM) and in normal controls (FC) using speckle tracking echocardiography (STE). Methods In this prospective study, the myocardial strain and dyssynchrony were analyzed using STE in a transversal four-chamber view in 180 fetuses (53 FDM, 127 FC) between 19 and 39 weeks of gestation. The measurements of the global and segmental longitudinal strain of both chambers (2C) and of the single left chamber (1C) were executed offline via QLab 10.5 (Philips Medical Systems, Andover, MA, USA). We assessed dyssynchrony as the time difference between peaks in strain in the mid segments of both chambers (interventricular dyssynchrony, 2C_DYS) and of the single left chamber (intraventricular dyssynchrony, 1C_DYS). Results Measurements were feasible with a high median frame rate of 199 frames/s (1st quartile: 174, 3rd quartile: 199). The global and segmental myocardial longitudinal strain of 2C and 1C were decreased and 2C_DYS and 1C_DYS were increased in pregnancies with diabetes compared to normal controls. Conclusion Our study demonstrates that fetal hearts affected by maternal diabetes mellitus (DM) show low myocardial strain values and high interventricular dyssynchrony. Two-chamber interventricular dyssynchrony has the potential to become a diagnostic marker for DM.

Detection of occult right ventricular dysfunction in young Egyptians with type 1 diabetes mellitus by two-dimensional speckle tracking echocardiography

Background

Type 1 diabetes mellitus (T1DM) is a common chronic disorder of childhood and adolescence. T1DM induced cardiomyopathy has a different entity than T2DM as it relies on different pathophysiological mechanisms, and rarely coexists with hypertension and obesity. Evaluation of right ventricular (RV) function in diabetic patients has been neglected despite the important contribution of RV to the overall cardiac function that affects the course and prognosis of diabetic cardiomyopathy (DCM).

Objective

To assess RV myocardial performance in asymptomatic T1DM using speckle tracking and standard echo parameters and correlate it with functional capacity using treadmill stress test.

Patients and methods

Thirty-nine patients with TIDM (Group 1, mean age 18.2 ± 1.7y, BMI = 26.2 ± 3.9 kg/m²), without cardiac problems and 15 apparently healthy matched subjects as a control group (Group 2, mean age 18.8 ± 2.3 y, BMI = 22.8 ± 3.3 kg/m²) were enrolled. RV function was evaluated using conventional, tissue Doppler and 2D speckle tracking echocardiography (2D-STE). The peak RV global longitudinal strain (RV-GLS) was obtained. Functional capacity was assessed by treadmill exercise test and estimated in metabolic equivalent (METs).

Results

In this study; the diabetic group showed statistically highly significant decrease in the average RV-GLS (−14.0 ± 6.9 in group 1 vs. −22.7 ± 2.5 in group 2, P < 0.001), significant decrease in RV S velocity (9.5 ± 2.2 in group 1 vs. 11.5 ± 1.8 in group 2, P < 0.05), significantly reduced E/A ratio (1.0 ± 0.2 in group 1 vs. 1.1 ± 0.1 in group 2, P < 0.05), and highly significant increased E/Em ratio (7.9 ± 3.2 in group 1 vs. 5.2 ± 0.7 in group 2, P < 0.001). We did not found any significant differences between the two groups regarding the other echocardiographic or functional capacity parameters.

Conclusion

In asymptomatic patients with T1DM, in addition to RV diastolic dysfunction, early (subclinical) RV systolic dysfunction is preferentially observed with normal RV and left ventricular (LV) ejection fraction (EF). 2D-STE has the ability to detect subclinical RV systolic dysfunction.

The obesity paradox: the protective effect of obesity on right ventricular function using echocardiographic strain imaging in patients with pulmonary hypertension

BACKGROUND

Obesity is associated with right ventricular (RV) dysfunction, but its effect on RV remodeling in patients with pulmonary hypertension (PHTN) has not been studied. We evaluated the effect of obesity, and its interplay with diabetes, in patients with PHTN using RV echocardiographic strain imaging.

METHODS

One hundred eighty-five patients underwent echocardiographic imaging and pulmonary artery pressure was calculated using tricuspid regurgitation jet velocity. From focused RV apical-four-chamber view, global and mid peak systolic RV free wall longitudinal strain (FWLS) was calculated using speckle-tracking software.

RESULTS

Global and mid RV FWLS in patients with PHTN (N.=84) was lower (-16.8±7 vs. 18.9±6.3, P=0.035 and -11.2±12.8 vs. -18.9±9.2, P=0.002 respectively) compared with patients without PHTN (N.=101). Among patients without PHTN, obese patients (BMI>30) had lower global and mid RV FWLS (-17.2±6.2 vs. -20.3±5.7, P=0.012 and -17.6±7.2 vs. -21.9±7.3, P=0.004), even after excluding diabetic patients (Mid RV FWLS -18.2±6.8 vs. -22.1±8, P=0.032). Among patients with PHTN, obese patients had similar RV FWLS compared with non-obese patients (P=0.46). However, on excluding diabetic patients from PHTN group, obese patients with PHTN had higher global and mid RV FWLS (-21.7±5.7 vs. -16.1±8, P=0.017 and 23.8±4.8 vs. -17±9.4, P=0.009 respectively) compared to non-obese patients which suggests a protective effect of obesity on RV function in patients with PHTN.

CONCLUSIONS

Obesity is associated with subclinical RV dysfunction as assessed by RV strain imaging, but paradoxically it may confer a protective effect on RV function once the patient develops PHTN. Future studies should evaluate the clinical impact of this paradox.

Comparison of speckle-tracking echocardiography with invasive hemodynamics for the detection of characteristic cardiac dysfunction in type-1 and type-2 diabetic rat models

Background

Measurement of systolic and diastolic function in animal models is challenging by conventional non-invasive methods. Therefore, we aimed at comparing speckle-tracking echocardiography (STE)-derived parameters to the indices of left ventricular (LV) pressure–volume (PV) analysis to detect cardiac dysfunction in rat models of type-1 (T1DM) and type-2 (T2DM) diabetes mellitus.

Methods

Rat models of T1DM (induced by 60 mg/kg streptozotocin, n = 8) and T2DM (32-week-old Zucker Diabetic Fatty rats, n = 7) and corresponding control animals (n = 5 and n = 8, respectively) were compared. Echocardiography and LV PV analysis were performed. LV short-axis recordings were used for STE analysis. Global circumferential strain, peak strain rate values in systole (SrS), isovolumic relaxation (SrIVR) and early diastole (SrE) were measured. LV contractility, active relaxation and stiffness were measured by PV analysis.

Results

In T1DM, contractility and active relaxation were deteriorated to a greater extent compared to T2DM. In contrast, diastolic stiffness was impaired in T2DM. Correspondingly, STE described more severe systolic dysfunction in T1DM. Among diastolic STE parameters, SrIVR was more decreased in T1DM, however, SrE was more reduced in T2DM. In T1DM, SrS correlated with contractility, SrIVR with active relaxation, while in T2DM SrE was related to cardiac stiffness, cardiomyocyte diameter and fibrosis.

Conclusions

Strain and strain rate parameters can be valuable and feasible measures to describe the dynamic changes in contractility, active relaxation and LV stiffness in animal models of T1DM and T2DM. STE corresponds to PV analysis and also correlates with markers of histological myocardial remodeling.

Electronic supplementary material

The online version of this article (10.1186/s12933-017-0645-0) contains supplementary material, which is available to authorized users.

Early detection of left ventricular diastolic dysfunction using conventional and speckle tracking echocardiography in a large animal model of metabolic dysfunction

Left ventricular (LV) diastolic dysfunction is one of the important mechanisms responsible for symptoms in patients with heart failure. The aim of the current study was to identify parameters that may be used to detect early signs of LV diastolic dysfunction in diabetic pigs on a high fat diet, using conventional and speckle tracking echocardiography. The study population consisted of 16 healthy Göttingen minipigs and 18 minipigs with experimentally induced metabolic dysfunction. Echocardiography measurements were performed at baseline and 3-month follow-up. The ratio of peak early (E) and late filling velocity (E/A ratio) and the ratio of E and the velocity of the mitral annulus early diastolic wave (E/Em ratio) did not change significantly in both groups. Peak untwisting velocity decreased in the metabolic dysfunction group (- 30.1 ± 18.5 vs. - 23.4 ± 15.5 °/ms) but not in controls (- 38.1 ± 23.6 vs. - 42.2 ± 23.0 °/ms), being significantly different between the groups at the 3-month time point (p < 0.05). In conclusion, whereas E/A ratio and E/Em ratio did not change significantly after 3 months of metabolic dysfunction, peak untwisting velocity was significantly decreased. Hence, peak untwisting velocity may serve as an important marker to detect early changes of LV diastolic dysfunction.

Subclinical left ventricular systolic and diastolic dysfunction in type 1 diabetic children and adolescents with good metabolic control

OBJECTIVE

Cardiac dysfunction is a well-known consequence of diabetes mellitus. This study was designed to assess whether type 1 diabetic children and adolescents with good metabolic control have early echocardiographic signs of subclinical left ventricular dysfunction and whether diabetes duration has any influence, using conventional and nonconventional echocardiographic tools.

METHODS

A total of 100 patients with type 1 diabetes mellitus and 80 gender- and age-matched healthy controls were included. The cases underwent standard conventional transthoracic echocardiography, tissue Doppler imaging, and two-dimensional speckle tracking echocardiography. None of the diabetic patients had signs of renal, retinal, or neurological complications of the disease, and all were good metabolic control (mean HbA_1c <7.5%).

RESULTS

There was no difference among groups in relation to age, sex, body mass index, and blood pressure. Conventional echocardiographic parameters were similar between diabetic and nondiabetic subjects except increased mitral valve peak A-wave and significantly lower mitral E/A ratio in diabetics. Diabetic patients had more advanced diastolic dysfunction with TDI analysis. In the diabetic group, left ventricular global longitudinal, circumferential, and radial strain and strain rate were significantly lower compared with the controls. There was a positive correlation between diabetes duration and cardiac dysfunction.

CONCLUSION

The results of this study showed that the diabetic children and adolescents with good metabolic control had diastolic dysfunction when assessed with either conventional or tissue Doppler echocardiography. Also diabetic patients had subclinical LV systolic dysfunction with a normal LVEF which can be detected with 2D speckle tracking echocardiography.

Evolution of subclinical myocardial dysfunction detected by two-dimensional and three-dimensional speckle tracking in asymptomatic type 1 diabetic patients: a long‑term follow-up study

Background

We sought to assess the long-term evolution of left ventricular (LV) function using two-dimensional (2D) and three-dimensional (3D) speckle tracking echocardiography (STE) for the detection of preclinical diabetic cardiomyopathy, in asymptomatic type 1 diabetic patients, over a 6-year follow-up.

Design and methods

Sixty-six asymptomatic type 1 diabetic patients with no cardiovascular risk factors were compared to 26 matched healthy controls. Conventional, 2D and 3D-STE were performed at baseline. A subgroup of 14 patients underwent a 6-year follow-up evaluation.

Results

At baseline, diabetic patients had similar LV ejection fraction (60 vs 61%; P = NS), but impaired longitudinal function, as assessed by 2D-global longitudinal strain (GLS) (−18.9 ± 2 vs −20.5 ± 2; P = 0.0002) and 3D-GLS (−17.5 ± 2 vs −19 ± 2; P = 0.003). At follow-up, diabetic patients had worsened longitudinal function compared to baseline (2D-GLS: −18.4 ± 1 vs −19.2 ± 1; P = 0.03). Global circumferential (GCS) and radial (GRS) strains were unchanged at baseline and during follow-up. Metabolic status did not correlate with GLS, whereas GCS and GRS showed a good correlation, suggestive of a compensatory increase of circumferential and radial functions in advanced stages of the disease – long-term diabetes (GCS: −26 ± 3 vs −23.3 ± 3; P = 0.008) and in the presence of microvascular complications (GRS: 38.8 ± 9 vs 34.3 ± 8; P = 0.04).

Conclusions

Subclinical myocardial dysfunction can be detected by 2D and 3D-STE in type 1 diabetic patients, independently of any other cardiovascular risk factors. Diabetic cardiomyopathy progression was suggested by a mild decrease in longitudinal function at the follow-up, but did not extend to a clinical expression of the disease, as no death or over heart failure was reported.

Diagnostic approaches for diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is a cardiac dysfunction which affects approximately 12% of diabetic patients, leading to overt heart failure and death. However, there is not an efficient and specific methodology for DCM diagnosis, possibly because molecular mechanisms are not fully elucidated, and it remains asymptomatic for many years. Also, DCM frequently coexists with other comorbidities such as hypertension, obesity, dyslipidemia, and vasculopathies. Thus, human DCM is not specifically identified after heart failure is established. In this sense, echocardiography has been traditionally considered the gold standard imaging test to evaluate the presence of cardiac dysfunction, although other techniques may cover earlier DCM detection by quantification of altered myocardial metabolism and strain. In this sense, Phase-Magnetic Resonance Imaging and 2D/3D-Speckle Tracking Echocardiography may potentially diagnose and stratify diabetic patients. Additionally, this information could be completed with a quantification of specific plasma biomarkers related to related to initial stages of the disease. Cardiotrophin-1, activin A, insulin-like growth factor binding protein-7 (IGFBP-7) and Heart fatty-acid binding protein have demonstrated a stable positive correlation with cardiac hypertrophy, contractibility and steatosis responses. Thus, we suggest a combination of minimally-invasive diagnosis tools for human DCM recognition based on imaging techniques and measurements of related plasma biomarkers.

Youth with type 1 diabetes have worse strain and less pronounced sex differences in early echocardiographic markers of diabetic cardiomyopathy compared to their normoglycemic peers: A RESistance to InSulin in Type 1 ANd Type 2 diabetes (RESISTANT) Study

OBJECTIVE

Diabetic cardiomyopathy is a major cause of morbidity, but limited data are available on early cardiac abnormalities in type 1 diabetes (T1D). We investigated differences in myocardial strain in adolescents with and without T1D. We hypothesized that adolescents with T1D would have worse strain than their normoglycemic peers, which boys would have worse strain than girls, and that strain would correlate with glycemic control and adipokines.

METHODS

We performed fasting laboratory measures and echocardiograms with speckle tracking to evaluate traditional echocardiographic measures in addition to longitudinal (LS) and circumferential (CS) strain, and in adolescents (15±2years) with (19 boys; 22 girls) and without (16 boys; 32 girls) type 1 diabetes.

RESULTS

Compared to controls, adolescents with type 1 diabetes had significantly lower CS (-20.9 vs. -22.7%, p=0.02), but not LS (p=0.83). Boys with T1D had significantly lower LS than girls with T1D (-17.5 vs. -19.7%, p=0.047), adjusted for Tanner stage. The significant sex differences observed in indexed left ventricular mass, left end-diastolic volume, diastolic septal and posterior wall thickness in our controls were lacking in adolescents with T1D.

CONCLUSIONS

Our observations suggest that youth with T1D have worse myocardial strain than normoglycemic peers. In addition, the relatively favorable cardiac profile observed in girls vs. boys in the control group, was attenuated in T1D. These early cardiovascular changes in youth with T1D are concerning and warrant longitudinal and mechanistic studies.

Tissue Doppler imaging is a sensitive echocardiographic technique to detect subclinical systolic and diastolic dysfunction of both ventricles in type 1 diabetes mellitus

Background

Subclinical left (LV) and right ventricular (RV) dysfunction has been demonstrated in type 2 diabetes mellitus and evidence indicates impaired LV diastolic function in type 1 diabetes mellitus (T1DM) as well. The aim of our study was to evaluate the role of tissue Doppler imaging (TDI) in assessment of global LV and RV function in T1DM patients.

Methods

A detailed two-dimensional, pulsed wave Doppler and pulsed wave TDI analysis was performed in 53 normotensive middle-aged T1DM patients and compared to healthy controls.

Results

In T1DM patients TDI analysis revealed reduced mean mitral septal and lateral E’ velocities as well as reduced mean tricuspid E˙t velocity compared to healthy controls (E’sept 8.89 ± 1.89 cm/s vs. 11.50 ± 2.41 cm/s, p < 0.001; E’lat 12.29 ± 2.58 cm/s vs.15.30 ± 2.95 cm/s, p < 0,001; E’t 13.56 ± 2.91 cm/s vs. 15.60 ± 2.99 cm/s, p = 0.001). Mean ratios E/E’sept, E/E’lat and E/E’t were significantly higher in diabetics with cutoff value of 7.4 for E/E’sept and 3.4 for E/E’t, differentiating diabetics with LV and RV diastolic impairement from matched healthy controls (sensitivity 76.5 %, specificity 73.8 % for E/E’sept and sensitivity 72.1 %, specificity 66.7 % for E/E’t). Myocardial acceleration during isovolumetric contraction (IVA) measured at the septal mitral (LV IVA) and lateral tricuspid annulus (RV IVA) was the only parameter indicating reduced contractility of both ventricles in diabetics compared to controls (LV IVA 230.70 ± 61.26 cm/s² vs. 283.32 ± 59.74 cm/s², p < 0,001; RV IVA 275.48 ± 68.08 cm/s² vs. 316.86 ± 80.95 cm/s², p = 0.011). LV IVA had better diagnostic accuracy than RV IVA to predict early contractile impairement in T1DM patients (area under the curve 0.758, p < 0.001 for LV IVA and 0.648, p = 0.017 for RV IVA).

Conclusions

TDI is essential to detect subclinical diastolic deterioration of both ventricles in T1DM patients. TDI-derived IVA might be useful to assess early systolic alterations of both ventricles in T1DM patients.