Left ventricular diastolic function in type 2 diabetes mellitus: prevalence and association with myocardial and vascular disease

Interdependence between myocardial deformation and perfusion in patients with T2DM and HFpEF: a feature-tracking and stress perfusion CMR study

BACKGROUND

Patients with diabetes have an increased risk of developing heart failure with preserved ejection fraction (HFpEF). This study aimed to compare indices of myocardial deformation and perfusion between patients with type 2 diabetes mellitus (T2DM) with and without HFpEF and to investigate the relationship between myocardial strain and perfusion reserve.

METHODS

This study included 156 patients with T2DM without obstructive coronary artery disease (CAD) and 50 healthy volunteers who underwent cardiac magnetic resonance (CMR) examination at our center. Patients with T2DM were subdivided into the T2DM-HFpEF (n = 74) and the T2DM-non-HFpEF (n = 82) groups. The parameters of left ventricular (LV) and left atrial (LA) strain as well as stress myocardial perfusion were compared. The correlation between myocardial deformation and perfusion parameters was also assessed. Mediation analyses were used to evaluate the direct and indirect effects of T2DM on LA strain.

RESULTS

Patients with T2DM and HFpEF had reduced LV radial peak systolic strain rate (PSSR), LV circumferential peak diastolic strain rate (PDSR), LA reservoir strain, global myocardial perfusion reserve index (MPRI), and increased LA booster strain compared to patients with T2DM without HFpEF (all P < 0.05). Furthermore, LV longitudinal PSSR, LA reservoir, and LA conduit strain were notably impaired in patients with T2DM without HFpEF compared to controls (all P < 0.05), but LV torsion, LV radial PSSR, and LA booster strain compensated for these alterations (all P < 0.05). Multivariate linear regression analysis demonstrated that LA reservoir and LA booster strain were independently associated with global MPRI (β = 0.259, P < 0.001; β =  - 0.326, P < 0.001, respectively). Further, the difference in LA reservoir and LA booster strain between patients with T2DM with and without HFpEF was totally mediated by global MPRI. Global stress PI, LA booster, global rest PI, and global MPRI showed high accuracy in diagnosing HFpEF among patients with T2DM (areas under the curve [AUC]: 0.803, 0.790, 0.740, 0.740, respectively).

CONCLUSIONS

Patients with T2DM and HFpEF exhibited significant LV systolic and diastolic deformation, decreased LA reservoir strain, severe impairment of myocardial perfusion, and elevated LA booster strain that is a compensatory response in HFpEF. Global MPRI was identified as an independent influencing factor on LA reservoir and LA booster strain. The difference in LA reservoir and LA booster strain between patients with T2DM with and without HFpEF was totally mediated by global MPRI, suggesting a possible mechanistic link between microcirculation impairment and cardiac dysfunction in diabetes. Myocardial perfusion and LA strain may prove valuable for diagnosing and managing HFpEF in the future.

Association of Visceral Adiposity Index and Handgrip Strength with Cardiometabolic Multimorbidity among Middle-Aged and Older Adults: Findings from Charls 2011-2020

The visceral adiposity index (VAI) and handgrip strength (HGS) are identified as important objectives for the prevention of illness. Nevertheless, there is limited understanding regarding the impact of the VAI and HGS on cardiometabolic multimorbidity (CMM). We aimed to ascertain the impact of the VAI and HGS on CMM among middle-aged and older people. Data spanning from 2011 to 2020 were derived from the China Health and Retirement Longitudinal Study (CHARLS). In total, 7909 individuals aged 45 years and older were included. Cox proportional hazard regression was utilized to examine the correlation among the VAI, HGS, and CMM. Throughout the 10-year follow-up, we determined that both the VAI (HR = 1.330; 95%CI = 1.179-1.500) and HGS (HR = 0.745, 95%CI = 0.645-0.861) exhibited significant associations with CMM risk. Individuals exposed to both a high VAI and low HGS were found to have higher hazards of CMM (HR = 1.377, 95%CI = 1.120-1.694) in contrast to participants exposed to one or none of these conditions. The older (HR = 1.414; 95%CI = 1.053-1.899) and male (HR = 1.586; 95%CI = 1.114-2.256) groups are more likely to experience CMM risk. Our findings suggest that both the VAI and HGS have significant effects on CMM risk. Appropriate interventions focused on vulnerable groups are recommended to prevent the incidence of CMM.

Epidemiology of heart failure in diabetes: a disease in disguise

Left ventricular diastolic dysfunction (LVDD) without symptoms, and heart failure (HF) with preserved ejection fraction (HFpEF) represent the most common phenotypes of HF in individuals with type 2 diabetes mellitus, and are more common than HF with reduced ejection fraction (HFrEF), HF with mildly reduced ejection fraction (HFmrEF) and left ventricular systolic dysfunction (LVSD) in these individuals. However, diagnostic criteria for HF have changed over the years, resulting in heterogeneity in the prevalence/incidence rates reported in different studies. We aimed to give an overview of the diagnosis and epidemiology of HF in type 2 diabetes, using both a narrative and systematic review approach; we focus narratively on diagnosing (using the 2021 European Society of Cardiology [ESC] guidelines) and screening for HF in type 2 diabetes. We performed an updated (2016-October 2022) systematic review and meta-analysis of studies reporting the prevalence and incidence of HF subtypes in adults ≥18 years with type 2 diabetes, using echocardiographic data. Embase and MEDLINE databases were searched and data were assessed using random-effects meta-analyses, with findings presented as forest plots. From the 5015 studies found, 209 were screened using the full-text article. In total, 57 studies were included, together with 29 studies that were identified in a prior meta-analysis; these studies reported on the prevalence of LVSD (n=25 studies, 24,460 individuals), LVDD (n=65 studies, 25,729 individuals), HFrEF (n=4 studies, 4090 individuals), HFmrEF (n=2 studies, 2442 individuals) and/or HFpEF (n=8 studies, 5292 individuals), and on HF incidence (n=7 studies, 17,935 individuals). Using Hoy et al's risk-of-bias tool, we found that the studies included generally had a high risk of bias. They showed a prevalence of 43% (95% CI 37%, 50%) for LVDD, 17% (95% CI 7%, 35%) for HFpEF, 6% (95% CI 3%, 10%) for LVSD, 7% (95% CI 3%, 15%) for HFrEF, and 12% (95% CI 7%, 22%) for HFmrEF. For LVDD, grade I was found to be most prevalent. Additionally, we reported a higher incidence rate of HFpEF (7% [95% CI 4%, 11%]) than HFrEF 4% [95% CI 3%, 7%]). The evidence is limited by the heterogeneity of the diagnostic criteria over the years. The systematic section of this review provides new insights on the prevalence/incidence of HF in type 2 diabetes, unveiling a large pre-clinical target group with LVDD/HFpEF in which disease progression could be halted by early recognition and treatment.Registration PROSPERO ID CRD42022368035.

[Impact of smoking on the presence of diabetic cardiomyopathy]

INTRODUCTION

Type 2 diabetes is associated with an increased risk of coronary disease and is the leading cause of morbidity and mortality in this population. The main objective of our work is to study the correlation of left atrial volume index with coronary disease in type 2 diabetics.

MATERIAL AND METHODS

Cross-sectional, analytical, single-center study with prospective recruitment of 330 type 2 diabetic patients carried out at the Constantine Regional Military University Hospital over a period of 03 years (2016-2018) among which 18.8% (62 patients) are smokers. Early cardiac involvement represented by diastolic dysfunction was assessed by two-dimensional transthoracic echocardiography. Data were analyzed using Epi info 7.2.1.0 software to study the impact of smoking on the presence of left ventricular diastolic dysfunction.

RESULTS

The average age of our cohort is 52.7 ± 8.4 years, an average of 7.1 ± 1.3% of glycated hemoglobin, an average of 5.3 ± 4.3 years of diabetes duration, a sex ratio to 1.01. 34.8% of patients had left atrial volume index ≥ 34 ml/m2. The prevalence of coronary disease is 27.0%. In multivariate analysis; left atrial volume index is significantly correlated with coronary stenosis (OR = 1.75, 95% CI [1.60 - 2.05], p = 0.02).

CONCLUSION

The prevalence of cardiomyopathy is high in type 2 diabetes and smoking is significantly correlated with the presence of this diabetic cardiomyopathy.

Left Ventricular Diastolic Dysfunction in Type 2 Diabetes Mellitus: A Single-Centre Observational Study From a Tertiary Care Hospital in South India

Background There is a high prevalence of left ventricular diastolic dysfunction (LVDD) in patients with type 2 diabetes mellitus (T2DM). The influencing factors of LVDD in T2DM are not fully understood.  Objective This study aimed at assessing the prevalence of LVDD in T2DM as well as looking at the association between various parameters related to T2DM with LVDD in patients with T2DM. Materials and methods This was a single-centre cross-sectional study in Kerala, India. The primary objective of the study was to assess the prevalence of LVDD in T2DM. The secondary objectives were to look for an association between higher glycated haemoglobin (HbA1c), complications of T2DM, age, and gender of the patient with the presence of LVDD. Results A total of 80 patients were included in the study. There were 40 patients with LVDD with a prevalence of 50%. There was a statistically significant positive association between increased age, longer duration of diabetes, higher HbA1C, the presence of diabetic neuropathy, diabetic retinopathy, and diabetic nephropathy with the prevalence of LVDD. A logistic regression analysis demonstrated that the presence of diabetic retinopathy is a risk factor for LVDD in the study subjects.

Diabetic microvascular complications are associated with left atrial structural alterations in asymptomatic type 2 diabetes patients: A cross-sectional study

AIMS

We used 4D-Auto LAQ to quantitatively evaluate the morphological and functional changes of left atrium in patients with asymptomatic type 2 diabetes mellitus (T2DM), and explored its correlations with diabetic microvascular complications (MICRO).

METHODS

This study included 319 patients with asymptomatic T2DM. According to the occurrence of MICRO, these patients were divided into 3 groups: patients with no complication, 1 complication, and 2-3 complications. 4D-Auto LAQ was used to evaluate left atrial volume (LAVImin, LAVImax, LAVIpre) and calculate the left atrial function (DEI, PEI, AEI) in different phases. Multiple linear regression was used to analyze the correlation between changes in left atrial volume and function and the number of MICROs in DM patients.

RESULTS

A total of 279 patients with asymptomatic T2DM were included in this study. (1) The ultrasound data of the three T2DM groups showed that there was no significant difference in left ventricular size and function among the three groups; (2) with the increase of MICRO number, the left atrial volume (LAVImin, LAVImax, LAVIpre) progressively increased, the left atrial storage function index (DEI) gradually decreased, and the differences were significant (P < 0.05). (3) Multiple linear regression analysis showed that: with the increase of MICRO number (no complication→1 complication→2-3 complications), the left atrial volume (LAVImin, LAVIpre) showed an increasing trend (both P < 0.05).

CONCLUSION

In asymptomatic T2DM patients, MICRO number showed a significant positive correlation with LAVImin and LAVIpre (P < 0.05). Therefore, the increase in left atrial volume can dynamically reflect the severity of microvascular lesions in patients with asymptomatic T2DM.

Role of continuous glucose monitoring in diabetic patients at high cardiovascular risk: an expert-based multidisciplinary Delphi consensus

Background

Continuous glucose monitoring (CGM) shows in more detail the glycaemic pattern of diabetic subjects and provides several new parameters (“glucometrics”) to assess patients’ glycaemia and consensually guide treatment. A better control of glucose levels might result in improvement of clinical outcome and reduce disease complications. This study aimed to gather an expert consensus on the clinical and prognostic use of CGM in diabetic patients at high cardiovascular risk or with heart disease.

Methods

A list of 22 statements concerning type of patients who can benefit from CGM, prognostic impact of CGM in diabetic patients with heart disease, CGM use during acute cardiovascular events and educational issues of CGM were developed. Using a two-round Delphi methodology, the survey was distributed online to 42 Italian experts (21 diabetologists and 21 cardiologists) who rated their level of agreement with each statement on a 5-point Likert scale. Consensus was predefined as more than 66% of the panel agreeing/disagreeing with any given statement.

Results

Forty experts (95%) answered the survey. Every statement achieved a positive consensus. In particular, the panel expressed the feeling that CGM can be prognostically relevant for every diabetic patient (70%) and that is clinically useful also in the management of those with type 2 diabetes not treated with insulin (87.5%). The assessment of time in range (TIR), glycaemic variability (GV) and hypoglycaemic/hyperglycaemic episodes were considered relevant in the management of diabetic patients with heart disease (92.5% for TIR, 95% for GV, 97.5% for time spent in hypoglycaemia) and can improve the prognosis of those with ischaemic heart disease (100% for hypoglycaemia, 90% for hyperglycaemia) or with heart failure (87.5% for hypoglycaemia, 85% for TIR, 87.5% for GV). The experts retained that CGM can be used and can impact the short- and long-term prognosis during an acute cardiovascular event. Lastly, CGM has a recognized educational role for diabetic subjects.

Conclusions

According to this Delphi consensus, the clinical and prognostic use of CGM in diabetic patients at high cardiovascular risk is promising and deserves dedicated studies to confirm the experts’ feelings.

Does diabetes increase the risk of cardiovascular events in patients with negative treadmill stress echocardiography?

Cardiovascular morbidity and mortality rates are considered to be high in patients with diabetes despite negative stress test results; however, little data are available to support this supposition. We compared the long-term cardiovascular events between patients with diabetes and those without diabetes with negative treadmill stress echocardiography and evaluated the predictors for cardiovascular events in patients with diabetes. A total of 1,243 consecutive patients (mean age, 56 ± 10 years; non-diabetics: diabetics, 975:268; mean follow-up of 5 years) with negative treadmill stress echocardiography were evaluated. Clinical data were examined, and major adverse cardiovascular events (MACEs, a composite of coronary revascularization, acute myocardial infarction, and cardiovascular death) were compared between the non-diabetic and diabetic groups. In the population matched by clinical characteristics, the diabetic and non-diabetic groups had similar occurrence of MACEs (non-diabetics vs. diabetics = 5% versus 7%; p = 0.329) and event-free survival. MACEs in the diabetic group were associated with elevated early diastolic velocity of the mitral inflow/mitral annulus (E/e') ratio, indicative of diastolic dysfunction. The absence of statin and dipeptidyl peptidase-4 inhibitor use and use of sulfonylureas were also predictors of more MACEs. In conclusion, long-term cardiovascular events in patients with diabetes and negative stress echocardiography were comparable to those in patients without diabetes. However, appropriate monitoring of diastolic dysfunction, statin use, and individualized antidiabetic drug selection are required to reduce the cardiovascular risk in patients with diabetes.

Diastolic Cardiac Function by MRI-Imaging Capabilities and Clinical Applications

Most cardiac studies focus on evaluating left ventricular (LV) systolic function. However, the assessment of diastolic cardiac function is becoming more appreciated, especially with the increasing prevalence of pathologies associated with diastolic dysfunction like heart failure with preserved ejection fraction (HFpEF). Diastolic dysfunction is an indication of abnormal mechanical properties of the myocardium, characterized by slow or delayed myocardial relaxation, abnormal LV distensibility, and/or impaired LV filling. Diastolic dysfunction has been shown to be associated with age and other cardiovascular risk factors such as hypertension and diabetes mellitus. In this context, cardiac magnetic resonance imaging (MRI) has the capability for differentiating between normal and abnormal myocardial relaxation patterns, and therefore offers the prospect of early detection of diastolic dysfunction. Although diastolic cardiac function can be assessed from the ratio between early and atrial filling peaks (E/A ratio), measuring different parameters of heart contractility during diastole allows for evaluating spatial and temporal patterns of cardiac function with the potential for illustrating subtle changes related to age, gender, or other differences among different patient populations. In this article, we review different MRI techniques for evaluating diastolic function along with clinical applications and findings in different heart diseases.

Prevalence and Predictors of Left Ventricular Diastolic Dysfunction in Malaysian Patients With Type 2 Diabetes Mellitus Without Prior Known Cardiovascular Disease

Objective: Existing data showed that left ventricular diastolic dysfunction is common in individuals with type 2 diabetes mellitus (T2DM). However, most of the studies included diabetic patients who have prior cardiovascular disease, which might be the compounding factor for ventricular dysfunction. This study aimed to determine the prevalence and predictors of left ventricular diastolic dysfunction in an Asian population with T2DM without prior cardiovascular disease using the latest recommended echocardiographic assessment for left ventricular diastolic dysfunction.

Design and Participants: This is a cross-sectional study in which eligible patients with T2DM without history of coronary artery disease, heart failure, or valvular heart disease were recruited. Demographic data, diabetic control, comorbidities, microvascular/macrovascular complications, and medications prescribed were recorded. Venous blood was sent to test for B-type natriuretic peptide, and transthoracic echocardiography was performed to assess left ventricular dysfunction.

Setting: This study was performed in a tertiary healthcare center located in Kuala Lumpur, Malaysia.

Results: Of the 301 patients, 83.1% have had T2DM for >10 years, with 45.8% being poorly controlled. Comorbidities include hypertension (77.1%), hyperlipidemia (91.0%), and pre-obesity/obesity (72.9%). Majority had absence of microvascular (albuminuria, retinopathy, and neuropathy) and macrovascular (peripheral vascular disease and stroke) complications. None had raised B-type natriuretic peptide levels, and 93.7% had no symptoms of heart failure. On echocardiographic assessment, 70.1% had left ventricular diastolic dysfunction, and 90.5% had Grade 1/mild severity. Age, ethnicity, insulin therapy, presence of hypertension, and hyperlipidemia were significantly associated with left ventricular diastolic dysfunction. Older T2DM patients of Chinese ethnicity and on insulin are about two times more likely to develop left ventricular diastolic dysfunction.

Conclusion: There was a high prevalence of asymptomatic left ventricular diastolic dysfunction among patients with T2DM without prior known cardiovascular disease. Older age, insulin therapy, and Chinese ethnicity were risk factors for left ventricular diastolic dysfunction in T2DM.

Comparison of empagliflozin and sitagliptin therapy on myocardial perfusion reserve in diabetic patients with coronary artery disease

BACKGROUND

Sodium-glucose co-transporter 2 inhibitors reduce the risk of cardiovascular events in type 2 diabetic patients with coronary artery disease (CAD); however, the underlying mechanisms remain unclear.

OBJECTIVES

We compared the effects of empagliflozin vs. sitagliptin therapy on myocardial perfusion reserve (MPR) using dynamic single-photon emission computed tomography (SPECT) imaging.

METHODS

In total, 100 patients with type 2 diabetes, CAD and an MPR <2.5 were randomized to receive either empagliflozin (10 mg once daily) or sitagliptin (100 mg once daily). Dynamic SPECT examinations were performed at baseline and at 6 months. The primary endpoint was the percent change of global MPR. Evaluable SPECT data were available for 98 patients.

RESULTS

Baseline clinical characteristics and SPECT data were well balanced between the two groups. At a 6-month follow-up, the fasting glucose and glycated hemoglobin levels significantly decreased in both groups. Hematocrit and hemoglobin levels significantly increased in the empagliflozin group but not in the sitagliptin group. The global MPR significantly improved after treatment in both groups (34.5 ± 70.6%; P = 0.005 for empagliflozin vs. 22.4 ± 45.7%; P = 0.024 for sitagliptin). However, there was no significant difference in the global MPR between the two groups (P = 0.934). Similar findings were detected with regard to the regional MPR.

CONCLUSION

Among patients with type 2 diabetes and CAD, both empagliflozin and sitagliptin significantly improved the global MPR with no significant difference between the groups.

Sex-specific pattern of left ventricular hypertrophy and diastolic function in patients with type 2 diabetes mellitus

AIMS

Few prospective studies have evaluated sex-specific pattern, natural progression of left ventricular (LV) remodelling, and diastolic dysfunction in patients with type 2 diabetes (T2DM). The aim of this study was to study the sex-specific prevalence, longitudinal changes of LV remodelling, and diastolic dysfunction in patients with T2DM. Further, the prognostic value of diastolic function in women and men was also evaluated.

METHODS AND RESULTS

A total of 350 patients with T2DM (mean age 61 ± 11 years; women, 48.3%) was recruited. Detailed echocardiography was performed at baseline and after 25 months. A major adverse cardiovascular event (MACE) was defined as cardiovascular death, heart failure hospitalization, or myocardial infarction. Despite a similar age, prevalence of hypertension and body mass index, women had a higher prevalence of LV hypertrophy and diastolic dysfunction at baseline and follow-up compared with men. A total of 21 patients developed MACE (5 cardiovascular death, 9 hospitalization for heart failure, and 7 myocardial infarction) during a median follow-up of 56 months. Women with diastolic dysfunction had a higher incidence of MACE than those with normal diastolic function but this association was neutral in men. Multivariable Cox-regression analysis indicated that diastolic dysfunction was associated with MACE in women [hazard ratio = 6.30; 95% confidence interval (CI) = 1.06-37.54; P < 0.05] but not men (hazard ratio = 2.29, 95% CI = 0.67-7.89; P = 0.19).

CONCLUSION

LV hypertrophy and diastolic dysfunction, both at baseline and follow-up, were more common in women than men. Pre-clinical diastolic dysfunction was independently associated with MACE only in women with T2DM but was neutral in men.

Evaluation of the effects of glycated hemoglobin on cardiac function in patients with short-duration type 2 diabetes mellitus: A cardiovascular magnetic resonance study

AIMS

To investigate the association between glycated hemoglobin (HbA1c) and myocardial dysfunction and to determine whether its association is independent of myocardial perfusion.

METHODS

Sixty-four patients with type 2 diabetes mellitus (T2DM) were recruited. They were divided into groups according to their HbA1c level: the controlled T2DM group (HbA1c < 7%) and uncontrolled T2DM groups (HbA1c ≥ 7%). Meanwhile, 30 age-matched healthy volunteers were included. All patients with T2DM and healthy controls underwent cardiovascular magnetic resonance imaging to evaluate the myocardial mechanics and perfusion parameters.

RESULTS

The circumferential and longitudinal peak strain (PS) (p = 0.009 and 0.002 respectively) and global radial, circumferential, and longitudinal peak strain diastolic strain rates (PDSRs) (p = 0.002, 0.001, and 0.001 respectively) were lower in the uncontrolled T2DM group than in the controls without diabetes. In multivariable linear regression analysis, HbA1c was independently related to all directions of the PS and PDSR. The myocardial perfusion parameters were not independently associated with the PS or PDSR.

CONCLUSIONS

Cardiac function is impaired in Chinese T2DM patients with poor glucose control (HbA1c ≥ 7%), with preserved left ventricular (LV) ejection fraction, and disease duration <10 years. Poor blood glucose control is an independent predictor of LV myocardial dysfunction for patients with short-term T2DM.

Comparison of Incidence of Myocardial Infarction in Patients With Rheumatoid Arthritis and Diabetes Mellitus

Introduction Patients with rheumatoid arthritis (RA) have a higher risk of cardiovascular diseases (CVDs) when compared to the general population, with most deaths attributed to myocardial infarctions (MI). However, patients with RA do not get the same attention in terms of cardiovascular screening as compared to other diseases, like diabetes mellitus (DM). Therefore, this study aims to compare the risk of CVD among patients with RA and DM. Methods This prospective study was carried out in Pakistan's two tertiary care hospitals. A total of 750 participants were enrolled in three groups with a 1:1:1 ratio; patients with RA, type 2 DM, and the control group. Patients were observed for 12 months or until the development of a major adverse cardiovascular event (MACE), whichever occurred first. Results Both fatal (12.66% vs. 13.48%; p-value: 0.79) and non-fatal (3.93% vs. 4.35%; p-value: 0.82) MI was comparable between both RA and DM group. However, compared to the control group, non-fatal MI (12.66% vs. 5.58%; p-value: 0.01) was significantly higher in the RA group. Conclusion Our study shows that RA and DM have an equal risk of cardiovascular (CV) events. It is important that RA should be considered as a prominent risk factor for CV events. The management of these patients should be multidisciplinary, including cardiologists.

Run for your life: can exercise be used to effectively target GLUT4 in diabetic cardiac disease?

The global incidence, associated mortality rates and economic burden of diabetes are now such that it is considered one of the most pressing worldwide public health challenges. Considerable research is now devoted to better understanding the mechanisms underlying the onset and progression of this disease, with an ultimate aim of improving the array of available preventive and therapeutic interventions. One area of particular unmet clinical need is the significantly elevated rate of cardiomyopathy in diabetic patients, which in part contributes to cardiovascular disease being the primary cause of premature death in this population. This review will first consider the role of metabolism and more specifically the insulin sensitive glucose transporter GLUT4 in diabetic cardiac disease, before addressing how we may use exercise to intervene in order to beneficially impact key functional clinical outcomes.

Management of Patients with Chronic Heart Failure and Diabetes Mellitus

Chronic heart failure (CHF) occurs in 4.3-28% of patients with diabetes mellitus and is most often associated with the presence of coronary heart disease, arterial hypertension and the direct adverse effects of insulin-resistance, hyperinsulinemia and hyperglycemia on the myocardium. Diabetes mellitus occurs in 12-47% of patients with CHF and can develop within several years after a diagnosis of HF in 22% of patients due to insulin-resistance of failure tissues. The presence of diabetes mellitus leads to a greater severity of clinical symptoms and hospitalization rate, worsening of quality of life and prognosis in CHF. A decreased left ventricular ejection fraction is an independent predictor of the poor prognosis in the patients with diabetes mellitus. The algorithm of the treatment of CHF in the patients with and without diabetes mellitus is not fundamentally different, but it requires taking into account the metabolic effects of the prescribed drugs. Angiotensin receptor-neprilysin inhibitor are increasingly used in clinical practice and are gradually replacing angiotensin-converting enzyme inhibitors and sartans in CHF both without diabetes mellitus and in its presence. Recently, the effectiveness of type 2 sodium glucose cotransporter inhibitors has been proven in patients with CHF with and without diabetes mellitus. This review is devoted to the relationship of diabetes mellitus and CHF, as well as the approaches to the management of such comorbid patients.

[Relationship between left ventricular diastolic dysfunction and coronary disease in type 2 diabetes mellitus]

INTRODUCTION

Type 2 diabetes is associated with an increased risk of coronary disease and is the leading cause of morbidity and mortality in this population. The main objective of our work is to study the correlation of diastolic function of the left ventricle with coronary disease in type 2 diabetics.

MATERIAL AND METHODS

Analytical cross-sectional, monocentric prospective-looking study of 703 type 2 diabetic patients performed at the Military Regional Hospital of Constantine over a period of 04 years (2016-2019). We excluded 338 patients who did not receive coronary angiography; thus 365 patients are ultimately analyzed. Evaluation of diastolic function was performed by two-dimensional transthoracic echocardiography with the search of coronary disease. The data was analyzed using the Epi Info 7.2.1.0 with study of the relationship of the diastolic function to coronary disease by multiple logistic regression.

RESULTS

The average age of our final cohort is 57,7±6,5 years, an average of 7.4±1.8% of glycated hemoglobin, an average of 5,8±4,1 years of diabetes, a sex ratio to 1.27. 49.3% had diastolic dysfunction. The prevalence of coronary disease is 32,9%. In multivariate analysis; diastolic dysfunction is correlated with coronary involvement significantly (OR=2.02, _95% CI [1.50 - 2.90], p=0.02).

CONCLUSION

The prevalence of diastolic dysfunction is high in type 2 diabetics and is significantly correlated with coronary heart disease.

The Impact of Antidiabetic Therapies on Diastolic Dysfunction and Diabetic Cardiomyopathy

Diabetic cardiomyopathy is more prevalent in people with type 2 diabetes mellitus (T2DM) than previously recognized, while often being characterized by diastolic dysfunction in the absence of systolic dysfunction. This likely contributes to why heart failure with preserved ejection fraction is enriched in people with T2DM vs. heart failure with reduced ejection fraction. Due to revised mandates from major health regulatory agencies, all therapies being developed for the treatment of T2DM must now undergo rigorous assessment of their cardiovascular risk profiles prior to approval. As such, we now have data from tens of thousands of subjects with T2DM demonstrating the impact of major therapies including the sodium-glucose co-transporter 2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor (GLP-1R) agonists, and dipeptidyl peptidase 4 (DPP-4) inhibitors on cardiovascular outcomes. Evidence to date suggests that both SGLT2 inhibitors and GLP-1R agonists improve cardiovascular outcomes, whereas DPP-4 inhibitors appear to be cardiovascular neutral, though evidence is lacking to determine the overall utility of these therapies on diastolic dysfunction or diabetic cardiomyopathy in subjects with T2DM. We herein will review the overall impact SLGT2 inhibitors, GLP-1R agonists, and DPP-4 inhibitors have on major parameters of diastolic function, while also highlighting the potential mechanisms of action responsible. A more complete understanding of how these therapies influence diastolic dysfunction will undoubtedly play a major role in how we manage cardiovascular disease in subjects with T2DM.

Consumption of animal and plant foods and risk of left ventricular diastolic dysfunction: the Bogalusa Heart Study

AIMS

Left ventricular diastolic dysfunction (LVDD) is an early heart failure with preserved ejection fraction (HFpEF) phenotype that is reversible. Identifying dietary predictors associated with LVDD in diverse populations may help broadly improve HFpEF primary prevention.

METHODS AND RESULTS

This longitudinal analysis included 456 individuals of the Bogalusa Heart Study (27% Black, 63% women, baseline age = 36.1 ± 4.4 years). Diet was measured at baseline through food frequency questionnaires. LVDD was defined at follow-up (median = 12.9 years) through echocardiographic measurement of the E/A ratio, E/e' ratio, isovolumic relaxation time, and deceleration time. Multivariable-adjusted logistic regression estimated the risk of LVDD according to dietary predictor, adjusting for traditional cardiovascular disease risk factors. Compared with the lowest tertile, participants in the middle tertile of total protein (OR = 3.30, 95% CI: 1.46, 7.45) and animal protein (OR = 2.91, 95% CI: 1.34, 6.34) consumption experienced the highest risk of LVDD. There was a 77% and 56% lower risk of LVDD for persons in the middle vs. lowest tertile of vegetable (OR = 0.23, 95% CI: 0.11, 0.49) and legume consumption (OR = 0.44, 95% CI: 0.22, 0.85), respectively. Total protein, animal protein, processed meat, and egg consumption indicated a quadratic trend towards increased risk of LVDD, while legume and vegetable intake conferred a quadratic trend towards decreased risk of LVDD (all quadratic P < 0.05).

CONCLUSIONS

Diets higher in animal foods and lower in plant foods are associated with an increased risk for LVDD. These findings suggest threshold effects of diet on LVDD, past which more traditional cardiometabolic determinants occupy a larger role in HFpEF risk.

Diabetes and Heart Failure: Is it Hyperglycemia or Hyperinsulinemia?

The cardiac effects of exogenously administered insulin for the treatment of diabetes (DM) have recently attracted much attention. In particular, it has been questioned whether insulin is the appropriate treatment for patients with type 2 diabetes mellitus and heart failure. While several old and some new studies suggested that insulin treatment has beneficial effects on the heart, recent observational studies indicate associations of insulin treatment with an increased risk of developing or worsening of pre-existing heart failure and higher mortality rates. However, there is actually little evidence that the associations of insulin administration with any adverse outcomes are causal. On the other hand, insulin clearly causes weight gain and may also cause serious episodes of hypoglycemia. Moreover, excess of insulin (hyperinsulinemia), as often seen with the use of injected insulin, seems to predispose to inflammation, hypertension, dyslipidemia, atherosclerosis, heart failure, and arrhythmias. Nevertheless, it should be stressed that most of the data concerning the effects of insulin on cardiac function derive from in vitro studies with isolated animal hearts. Therefore, the relevance of the findings of such studies for humans should be considered with caution. In the present review, we summarize the existing data about the potential positive and negative effects of insulin on the heart and attempt to answer the question whether any adverse effects of insulin or the consequences of hyperglycemia are more important and may provide a better explanation of the close association of DM with heart failure.

Prevalence of Cardiovascular Disease in Patients with Type 2 Diabetes Mellitus in Iran: A Systematic Review and Meta-Analysis

BACKGROUND

Type 2 diabetes mellitus (DM) is the most common type of DM and accounts for 90% of the cases. One of the most important complications of type 2 DM is cardiovascular complications, which are the most common cause of mortality in patients with DM. Various studies have reported different incidence rates of cardiovascular disease in patients with type 2 DM. However, no comprehensive review of previous studies has been done. This study is aimed at determining the prevalence of cardiovascular disease in patients with type 2 diabetes mellitus in Iran with a systematic review and meta-analysis.

METHODS

In this review, studies were first extracted searching domestic and international databases including SID, MagIran, IranMedex, IranDoc, Cochrane, Embase, ScienceDirect, Scopus, PubMed, and Web of Science (ISI), published between 2001 and September 2019. The random effects model was adopted for the analysis, and heterogeneity of the extracted studies was investigated with the I ² index. The data collected from the extracted studies were analyzed using a comprehensive meta-analysis (Version 2) software.

RESULTS

The prevalence of cardiovascular disease in patients with type 2 DM in Iran in 17 studies with a sample size of 9656 was 37.4% (95% CI: 31.4-43.8). Based on meta-regression, there was a significant difference on the effect of year of conducting the study and sample size with the prevalence of cardiovascular disease in patients with type 2 DM in Iran (p ≤ 0.001).

CONCLUSION

The results of this study indicated that there was a high prevalence rate of cardiovascular disease in patients with type 2 DM in Iran. Therefore, appropriate strategies should be taken to improve this situation and trace and supervise it at all levels, providing feedback to hospitals.

Consensus recommendations for management of patients with type 2 diabetes mellitus and cardiovascular diseases

The recent American Diabetes Association and the European Association for the Study of Diabetes guideline mentioned glycaemia management in type 2 diabetes mellitus (T2DM) patients with cardiovascular diseases (CVDs); however, it did not cover the treatment approaches for patients with T2DM having a high risk of CVD, and treatment and screening approaches for CVDs in patients with concomitant T2DM. This consensus guideline undertakes the data obtained from all the cardiovascular outcome trials (CVOTs) to propose approaches for the T2DM management in presence of CV comorbidities. For patients at high risk of CVD, metformin is the drug of choice to manage the T2DM to achieve a patient specific HbA1c target. In case of established CVD, a combination of glucagon-like peptide-1 receptor agonist with proven CV benefits is recommended along with metformin, while for chronic kidney disease or heart failure, a sodium-glucose transporter proteins-2 inhibitor with proven benefit is advised. This document also summarises various screening and investigational approaches for the major CV events with their accuracy and specificity along with the treatment guidance to assist the healthcare professionals in selecting the best management strategies for every individual. Since lifestyle modification and management plays an important role in maintaining the effectiveness of the pharmacological therapies, authors of this consensus recommendation have also briefed on the patient-centric non-pharmacological management of T2DM and CVD.

GLUT4 expression and glucose transport in human induced pluripotent stem cell-derived cardiomyocytes

Induced pluripotent stem cell derived cardiomyocytes (iPSC-CM) have the potential to transform regenerative cardiac medicine and the modelling of cardiac disease. This is of particular importance in the context of diabetic cardiomyopathy where diabetic individuals exhibit reduced cardiac diastolic contractile performance in the absence of vascular disease, significantly contributing towards high cardiovascular morbidity. In this study, the capacity of iPSC-CM to act as a novel cellular model of cardiomyocytes was assessed. The diabetic phenotype is characterised by insulin resistance, therefore there was a specific focus upon metabolic parameters. Despite expressing crucial insulin signalling intermediates and relevant trafficking proteins, it was identified that iPSC-CM do not exhibit insulin-stimulated glucose uptake. iPSC-CM are spontaneously contractile however contraction mediated uptake was not found to mask any insulin response. The fundamental limitation identified in these cells was a critical lack of expression of the insulin sensitive glucose transporter GLUT4. Using comparative immunoblot analysis and the GLUT-selective inhibitor BAY-876 to quantify expression of these transporters, we show that iPSC-CM express high levels of GLUT1 and low levels of GLUT4 compared to primary cardiomyocytes and cultured adipocytes. Interventions to overcome this limitation were unsuccessful. We suggest that the utility of iPSC-CMs to study cardiac metabolic disorders may be limited by their apparent foetal-like phenotype.

Revisiting the Cardiotoxic Effect of Chloroquine

PURPOSE

Cardiotoxicity is a well-known side effect of chloroquine. Several studies have proposed chloroquine as a potential anti-diabetic treatment but do not address this problem. The current study investigated the effect of ex vivo chloroquine treatment on (1) heart function and glucose uptake, (2) mitochondrial function and (3) in vivo treatment on heart function.

METHODS

Control or obese male Wistar rats were used throughout. Dose responses of increasing chloroquine concentrations versus vehicle on cardiac function were measured using isolated, Langendorff-perfused hearts whilst glucose uptake and cell viability were determined in ventricular cardiomyocytes. Mitochondrial function was assessed with a Clark-type oxygraph (Hansatech) after ex vivo perfusion with 30 μM chloroquine versus vehicle. Animals were treated orally with 5 mg/kg/day chloroquine for 6 weeks.

RESULTS

Acute chloroquine treatment of 10 μM was sufficient to significantly decrease heart function (p < 0.05) whilst 30 μM significantly reduced heart rate (p < 0.05). Chloroquine became toxic to isolated cardiomyocytes at high concentrations (100 μM), and had no effect on cardiomyocyte glucose uptake. Ex vivo treatment did not affect mitochondrial function, but chronic low-dose in vivo chloroquine treatment significantly decreased aortic output and total work in hearts (p < 0.005).

CONCLUSION

Low and intermediate chloroquine doses administered either chronically or acutely are sufficient to result in myocardial dysfunction.

An echocardiographic substrate for dyspnea identifies high risk patients with type 2 diabetes

BACKGROUND

Dyspnea is a common clinical challenge in patients with type 2 diabetes and may be a sign of heart failure (HF). We sought to evaluate the predictive value dyspnea with and without an echocardiographic substrate in patients with type 2 diabetes without known heart disease.

METHODS

A total of 724 patients with type 2 diabetes followed at specialized clinics participated in this prospective cohort study. Clinical evaluation, comprehensive echocardiography and follow-up through national registers were performed. An echocardiographic substrate was either left ventricular hypertrophy, increased left atrial size, E/e' > 15, or LV ejection fraction<50%. The end-points were cardiovascular (CVD) events and all-cause mortality.

RESULTS

Median follow-up was 4.8 years [Interquartile range: 4.1, 5.3] for CVD event and 77 patients suffered a CVD event. Dyspnea was significantly associated with CVD event: Hazard ratio (HR): 1.58 (95% confidence interval: 1.01-2.48), p = 0.04. Stratifying by evidence of echocardiographic substrate revealed high risk individuals: CVD event: 0.71 (0.35-1.46), p = NS in patients with dyspnea and no echocardiographic substrate and 2.85 (1.74-4.67), p < 0.001 in patients with dyspnea with echocardiographic substrate). This pattern was similar in multivariable analyses. Also, C-statistics improved from 0.66 (0.60-0.72) to 0.69 (0.63-0.75), p < 0.001 and net reclassification index was 27.5%(5.0-50.0), p = 0.01 for CVD event. The results were similar for all-cause mortality except dyspnea was only a borderline significant predictor.

CONCLUSION

In patients with type 2 diabetes complaining of dyspnea, identifying an echocardiographic substrate - thus indicating patients with HF - accurately stratifies patients with increased risk of CV events and all-cause mortality.

Visit-to-visit fasting plasma glucose variability is an important risk factor for long-term changes in left cardiac structure and function in patients with type 2 diabetes

BACKGROUND

To investigate the effect of visit-to-visit fasting plasma glucose (FPG) variability on the left cardiac structure and function in patients with type 2 diabetes mellitus (T2DM).

METHODS

In this prospective cohort study, 455 T2DM patients were included and follow-up for a median of 4.7 years. FPG measured on every hospital visit was collected. FPG variability was calculated by its coefficient of variation (CV-FPG). Left cardiac structure and function were assessed using echocardiography at baseline and after follow-up. Multivariable linear regression analyses were used to estimate the effect of FPG variability on the annualized changes in left cardiac structure and function. Subgroup analysis stratified by mean HbA1c levels (< 7% and ≥ 7%) were also performed.

RESULT

In multivariable regression analyses, CV-FPG was independently associated with the annualized changes in left ventricle (β = 0.137; P = 0.031), interventricular septum (β = 0.215; P = 0.001), left ventricular posterior wall thickness (β = 0.129; P = 0.048), left ventricular mass index (β = 0.227; P < 0.001), and left ventricular ejection fraction (β = - 0.132; P = 0.030). After additionally stratified by mean HbA1c levels, CV-FPG was still independently associated with the annualized changes in the above parameters in patients with HbA1c ≥ 7%, while not in patients with HbA1c < 7%.

CONCLUSIONS

Visit-to-visit variability in FPG could be a novel risk factor for the long-term adverse changes in left cardiac structure and systolic function in patients with type 2 diabetes. Trial registration ClinicalTrials.gov (NCT02587741), October 27, 2015, retrospectively registered.

Diabetic Cardiomyopathy Modelling Using Induced Pluripotent Stem Cell Derived Cardiomyocytes: Recent Advances and Emerging Models

The global burden of diabetes has drastically increased over the past decades and in 2017 approximately 4 million deaths were caused by diabetes and cardiovascular complications. Diabetic cardiomyopathy is a common complication of diabetes with early manifestations of diastolic dysfunction and left ventricular hypertrophy with subsequent progression to systolic dysfunction and ultimately heart failure. An in vitro model accurately recapitulating key processes of diabetic cardiomyopathy would provide a useful tool for investigations of underlying disease mechanisms to further our understanding of the disease and thereby potentially advance treatment strategies for patients. With their proliferative capacity and differentiation potential, human induced pluripotent stem cells (iPSCs) represent an appealing cell source for such a model system and cardiomyocytes derived from induced pluripotent stem cells have been used to establish other cardiovascular related disease models. Here we review recently made advances and discuss challenges still to be overcome with regard to diabetic cardiomyopathy models, with a special focus on iPSC-based systems. Recent publications as well as preliminary data presented here demonstrate the feasibility of generating cardiomyocytes with a diabetic phenotype, displaying insulin resistance, impaired calcium handling and hypertrophy. However, capturing the full metabolic- and functional phenotype of the diabetic cardiomyocyte remains to be accomplished.

Diastolic dysfunction and exercise capacity in patients with metabolic syndrome and overweight/obesity

Background

Left ventricle diastolic dysfunction (LVDD) is a common finding in high risk individuals, its presence being associated with reduced exercise capacity (EC). We assessed the prevalence of LVDD, applying the 2016 guidelines of the American Society of Echocardiography (ASE)/European Association of Cardiovascular Imaging (EACVI), in a population with overweight/obesity and metabolic syndrome and its association with EC.

Methods and results

This was a prospective, cross-sectional study of a cohort of 235 patients (mean age of 65 ± 5 years old and 33% female) without heart disease and an ejection fraction >50% who underwent a complete echocardiographic assessment and cardiopulmonary exercise testing. Individuals meeting three or more criteria of the 2016 ASE/EACVI guidelines are considered to have LVDD, while tests are considered indeterminate in those meeting only two. Overall, 178 (76%) of our patients met one echocardiographic cutoff value for LVDD, 91 (39%) met two and 7 (3%) three or more. Patients meeting three cutoffs values showed a significant reduction in maximal oxygen uptake (16 ± 3 vs. 19.6 ± 5 ml/kg/min, p < .05), unlike those with indeterminate tests. In multiple regression analysis, meeting three cutoffs was associated with number of METS (ß = −2.2, p = .018). In exploratory analysis, using two criteria based on cutoffs different from those proposed in the guidelines, we identified groups with different EC.

Conclusions

The application of 2016 ASE/EACVI guidelines limited the prevalence of LVDD to 3%. This group showed a clear reduction of the EC. New echocardiographic cutoff values proposed in this study allow us to establish subgroups with different levels of EC.

Cardiac SNARE Expression in Health and Disease

SNARE proteins are integral to intracellular vesicular trafficking, which in turn is the process underlying the regulated expression of substrate transporters such as the glucose transporter GLUT4 at the cell surface of insulin target tissues. Impaired insulin stimulated GLUT4 trafficking is associated with reduced cardiac function in many disease states, most notably diabetes. Despite this, our understanding of the expression and regulation of SNARE proteins in cardiac tissue and how these may change in diabetes is limited. Here we characterize the array of SNARE proteins expressed in cardiac tissue, and quantify the levels of expression of VAMP2, SNAP23, and Syntaxin4-key proteins involved in insulin-stimulated GLUT4 translocation. We examined SNARE protein levels in cardiac tissue from two rodent models of insulin resistance, db/db mice and high-fat fed mice, and show alterations in patterns of expression are evident. Such changes may have implications for cardiac function.

The prevalence of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction in men and women with type 2 diabetes: A systematic review and meta-analysis

OBJECTIVE

Type 2 diabetes is a risk factor for the development of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction. Our aim was to provide a summary estimate of the prevalence of left ventricular diastolic dysfunction and heart failure with preserved ejection fraction in type 2 diabetes patients and to investigate sex disparities.

METHODS AND RESULTS

A systematic search of the databases Medline and Embase was conducted for studies reporting the prevalence of left ventricular diastolic dysfunction or heart failure with preserved ejection fraction among type 2 diabetes patients. Studies were only included if echocardiography was performed. Prevalence estimates were pooled using random-effects meta-analysis. A total of 28 studies were included. Data on the prevalence of left ventricular diastolic dysfunction were available in 27 studies. The pooled prevalence for left ventricular diastolic dysfunction in the hospital population (2959 type 2 diabetes participants) and in the general population (2813 type 2 diabetes participants) was 48% [95% confidence interval: 38%-59%] and 35% (95% confidence interval: 24%-46%), respectively. Heterogeneity was high in both populations, with estimates ranging from 19% to 81% in the hospital population and from 23% to 54% in the general population. For women and men, the pooled prevalence estimates of left ventricular diastolic dysfunction were 47% (95% confidence interval: 37%-58%) and 46% (95% confidence interval: 37%-55%), respectively. Only two studies presented the prevalence of heart failure with preserved ejection fraction; 8% (95% confidence interval: 5%-14%) in a hospital population and 25% (95% confidence interval: 21%-28%) in the general population [18% in men (mean age: 73.8; standard deviation: 8.6) and 28% in women (mean age: 74.9; standard deviation: 6.9)].

CONCLUSION

The prevalence of left ventricular diastolic dysfunction among type 2 diabetes patients is similarly high in men and women, while heart failure with preserved ejection fraction seems to be more common in women than men, at least in community people with type 2 diabetes.

Left ventricular subclinical myocardial dysfunction in uncomplicated type 2 diabetes mellitus is associated with impaired myocardial perfusion: a contrast-enhanced cardiovascular magnetic resonance study

BACKGROUND

Early detection of subclinical myocardial dysfunction in patients with diabetes mellitus (DM) is essential for recommending therapeutic interventions that can prevent or reverse heart failure, thereby improving the prognosis in such patients. This study aims to quantitatively evaluate left ventricular (LV) myocardial deformation and perfusion using cardiovascular magnetic resonance (CMR) imaging in patients with type 2 diabetes mellitus (T2DM), and to investigate the association between LV subclinical myocardial dysfunction and coronary microvascular perfusion.

METHODS

We recruited 71 T2DM patients and 30 healthy individuals as controls who underwent CMR examination. The T2DM patients were subdivided into two groups, namely the newly diagnosed DM group (n = 31, patients with diabetes for ≤ 5 years) and longer-term DM group (n = 40, patients with diabetes > 5 years). LV deformation parameters, including global peak strain (PS), peak systolic strain rate, and peak diastolic strain rate (PSDR), and myocardial perfusion parameters such as upslope, time to maximum signal intensity (TTM), and max signal intensity (Max SI, were measured and compared among the three groups. Pearson's correlation was used to evaluate the correlation between LV deformation and perfusion parameters.

RESULTS

Pooled data from T2DM patients showed a decrease in global longitudinal, circumferential, and radial PDSR compared to healthy individuals, apart from lower upslope. In addition, increased TTM and reduced Max SI were found in the longer-term diabetics compared to the normal subjects (p < 0.017 for all). Multivariable linear regression analysis showed that T2DM was independently associated with statistically significant CMR parameters, except for TTM (β = 0.137, p = 0.195). Further, longitudinal PDSR was significantly associated with upslope (r = - 0.346, p = 0.003) and TTM (r = 0.515, p < 0.001).

CONCLUSIONS

Our results imply that a contrast-enhanced 3.0T CMR can detect subclinical myocardial dysfunction and impaired myocardial microvascular perfusion in the early stages of T2DM, and that the myocardial dysfunction is associated with impaired coronary microvascular perfusion.

Prevalence of left ventricular systolic dysfunction and heart failure with reduced ejection fraction in men and women with type 2 diabetes mellitus: a systematic review and meta-analysis

BACKGROUND

Type 2 diabetes mellitus (T2D) is associated with the development of left ventricular systolic dysfunction (LVSD) and heart failure with reduced ejection fraction (HFrEF). T2D patients with LVSD are at higher risk of mortality and morbidity than patients without LVSD, while progression of LVSD can be delayed or halted by the use of proven therapies. As estimates of the prevalence are scarce and vary considerably, the aim of this study was to retrieve summary estimates of the prevalence of LVSD/HFrEF in T2D and to see if there were any sex differences.

METHODS

A systematic search of Medline and Embase was performed to extract the prevalence of LVSD/HFrEF in T2D (17 studies, mean age 50.1 ± 6.3 to 71.5 ± 7.5), which were pooled using random-effects meta-analysis.

RESULTS

The pooled prevalence of LVSD was higher in hospital populations (13 studies, n = 5835, 18% [95% CI 17-19%]), than in the general population (4 studies, n = 1707, 2% [95% CI 2-3%]). Seven studies in total reported sex-stratified prevalence estimates (men: 7% [95% CI 5-8%] vs. women: 1.3% [95% CI 0.0.2.2%]). The prevalence of HFrEF was available in one general population study (5.8% [95% CI 3.7.6%], men: 6.8% vs. women: 3.0%).

CONCLUSIONS

The summary prevalence of LVSD is higher among T2D patients from a hospital setting compared with from the general population, with a higher prevalence in men than in women in both settings. The prevalence of HFrEF among T2D in the population was only assessed in a single study and again was higher among men than women.

The role of dipeptidylpeptidase-4 inhibitors in management of cardiovascular disease in diabetes; focus on linagliptin

Multiple population based analyses have demonstrated a high incidence of cardiovascular disease (CVD) and cardiovascular (CV) mortality in subjects with T2DM that reduces life expectancy by as much as 15 years. Importantly, the CV system is particularly sensitive to the metabolic and immune derangements present in obese pre-diabetic and diabetic individuals; consequently, CV dysfunction is often the initial CV derangement to occur and promotes the progression to end organ/tissue damage in T2DM. Specifically, diabetic CVD can manifest as microvascular complications, such as nephropathy, retinopathy, and neuropathy, as well as, macrovascular impairments, including ischemic heart disease, peripheral vascular disease, and cerebrovascular disease. Despite some progress in prevention and treatment of CVD, mainly via blood pressure and dyslipidemia control strategies, the impact of metabolic disease on CV outcomes is still a major challenge and persists in proportion to the epidemics of obesity and diabetes. There is abundant pre-clinical and clinical evidence implicating the DPP-4-incretin axis in CVD. In this regard, linagliptin is a unique DPP-4 inhibitor with both CV and renal safety profiles. Moreover, it exerts beneficial CV effects beyond glycemic control and beyond class effects. Linagliptin is protective for both macrovascular and microvascular complications of diabetes in preclinical models, as well as clinical models. Given the role of endothelial-immune cell interactions as one of the key events in the initiation and progression of CVD, linagliptin modulates these cell–cell interactions by affecting two important pathways involving stimulation of NO signaling and potent inhibition of a key immunoregulatory molecule.

Type 2 diabetes mellitus and heart failure: a position statement from the Heart Failure Association of the European Society of Cardiology

The coexistence of type 2 diabetes mellitus (T2DM) and heart failure (HF), either with reduced (HFrEF) or preserved ejection fraction (HFpEF), is frequent (30-40% of patients) and associated with a higher risk of HF hospitalization, all-cause and cardiovascular (CV) mortality. The most important causes of HF in T2DM are coronary artery disease, arterial hypertension and a direct detrimental effect of T2DM on the myocardium. T2DM is often unrecognized in HF patients, and vice versa, which emphasizes the importance of an active search for both disorders in the clinical practice. There are no specific limitations to HF treatment in T2DM. Subanalyses of trials addressing HF treatment in the general population have shown that all HF therapies are similarly effective regardless of T2DM. Concerning T2DM treatment in HF patients, most guidelines currently recommend metformin as the first-line choice. Sulphonylureas and insulin have been the traditional second- and third-line therapies although their safety in HF is equivocal. Neither glucagon-like preptide-1 (GLP-1) receptor agonists, nor dipeptidyl peptidase-4 (DPP4) inhibitors reduce the risk for HF hospitalization. Indeed, a DPP4 inhibitor, saxagliptin, has been associated with a higher risk of HF hospitalization. Thiazolidinediones (pioglitazone and rosiglitazone) are contraindicated in patients with (or at risk of) HF. In recent trials, sodium-glucose co-transporter-2 (SGLT2) inhibitors, empagliflozin and canagliflozin, have both shown a significant reduction in HF hospitalization in patients with established CV disease or at risk of CV disease. Several ongoing trials should provide an insight into the effectiveness of SGLT2 inhibitors in patients with HFrEF and HFpEF in the absence of T2DM.

Left atrial function: evaluation by strain analysis

The left atrium has an important role in modulating left ventricular filling and is an important biomarker of cardiovascular disease and adverse cardiovascular outcomes. While previously left atrial (LA) size was utilised, the role of LA function as a biomarker is increasingly being evaluated, both independently and also in combination with LA size. Strain analysis has been utilised for evaluation of LA function and can be measured throughout the cardiac cycle, thereby enabling the evaluation of LA reservoir, conduit and contractile function. Strain evaluates myocardial deformation while strain rate examines the rate of change in strain. This review will focus on the various types of strain analysis for evaluation of LA function, alterations in LA strain in physiological and pathologic states that alter LA function and finally evaluate its utility as a prognostic marker.

Assessment of left atrial function in patients with type 2 diabetes mellitus with a disease duration of six months

INTRODUCTION

Changes in left atrial (LA) size and function are associated with adverse clinical events. Recently, duration of diabetes mellitus (DM2) has been found to be positively associated with increased LA volume and impaired LA function. This study was performed, using two-dimensional echocardiograpy, to evaluate the changes in LA volume and function in patients with DM2 with a disease duration of six months, and to assess the parameters that affect LA volume and function.

METHODS

Fifty-six patients (28 male, age: 52.6 ± 6.5 years) with DM2 and 56 controls (24 male; age: 50.1 ± 7.0 years) were enrolled in the study. Each subject underwent conventional two-dimensional echocardiography to assess LA volume (indexed maximal LA volume: Vmax, pre-atrial contraction volume: Volp, minimal LA volume: Vmin) and LA function [passive emptying volume - passive emptying fraction (PEV - PEF), active emptying volume - active emptying fraction (AEV - AEF), total emptying volume - total emptying fraction (TEV - TEF) ].

RESULTS

LA diameter, indexed Vmax, Volp, Vmin, AEV and TEV were found to be significantly higher in the DM2 group compared with the controls (p < 0.05). Indexed Vmax, Volp and Vmin were significantly correlated with HbA1c level, body mass index (BMI), high-sensitivity C-reactive protein and uric acid levels, mitral A wave, E/E' ratio and A' wave. According to multivariate analysis, age and BMI had a statistically significant effect on LA volume.

CONCLUSION

Impaired LA function may be present in patients with newly diagnosed DM2. BMI and increasing age caused LA enlargement and LA volumes that were independent of the effects of hypertension and DM2.

Cardiac Adaptations to High-Intensity Aerobic Training in Premenopausal and Recent Postmenopausal Women: The Copenhagen Women Study

BACKGROUND

We examined the role of menopause on cardiac dimensions and function and assessed the efficacy of exercise training before and after menopause.

METHODS AND RESULTS

Two groups of healthy premenopausal (n=36, 49.4±0.3 years) and postmenopausal (n=37, 53.5±0.5 years) women with no history of cardiovascular disease and with a mean age difference between groups of only 4 years were studied. Cardiac dimensions and systolic and diastolic function were determined by transthoracic echocardiography with tissue Doppler imaging and 2-dimensional speckle tracking. Measurements were performed at baseline and after a 12-week period of high-intensity aerobic cycle training. LV internal diastolic diameter and LV mass were similar in the 2 groups at baseline and increased by ≈2% to 8% (P=0.04-0.0007) with training in both groups. Left atrial end-diastolic and end-systolic volumes were similar for both groups and increased by 23% to 36% (P=0.0006-0.0001) with training. Systolic function assessed by mean global strain was similar in both groups at baseline and increased by ≈8% (P=0.0004) with training in the postmenopausal group. LV displacement increased by ≈3% (P=0.04) in the premenopausal women only. Diastolic function assessed by E/A ratio was similar at baseline and increased by ≈7% (P=0.01) in the premenopausal group and 11% (P=0.0001) in the postmenopausal group with training.

CONCLUSIONS

These results suggest that training-induced cardiac adaptations are preserved in the early postmenopausal phase. Furthermore, the hormonal changes associated with the menopausal transition do not appear to affect cardiac dimensions and function.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02135575.

Cardiovascular Autonomic Neuropathy Is an Independent Risk Factor for Left Ventricular Diastolic Dysfunction in Patients with Type 2 Diabetes

Aim

This study aimed to evaluate the association between cardiovascular autonomic neuropathy (CAN) and left ventricular diastolic dysfunction (LVDD) in type 2 diabetes patients.

Methods

315 type 2 diabetes patients from inpatients of Drum Tower Hospital were included and classified into no CAN (NCAN), possible CAN (PCAN), and definite CAN (DCAN) based on cardiovascular autonomic reflex tests. The left ventricular diastolic function was assessed by tissue Doppler imaging echocardiography.

Results

The distribution of NCAN, PCAN, and DCAN was 11.4%, 51.1%, and 37.5%, respectively. The proportion of LVDD increased among the groups of NCAN, PCAN, and DCAN (39.4%, 45.3%, and 68.0%, P = 0.001). Patients with DCAN had higher filling pressure (E/e′ ratio) (10.9 ± 2.7 versus 9.4 ± 2.8, P = 0.013) and impaired diastolic performance (e′) (6.8 ± 1.7 versus 8.6 ± 2.4, P = 0.004) compared with NCAN. CAN was found to be an independent risk factor for LVDD from the multivariate regression analysis (OR = 1.628, P = 0.009, 95% CI 1.131–2.344).

Conclusions

Our results indicated that CAN was an independent risk marker for the presence of LVDD in patients with diabetes. Early diagnosis and treatment of CAN are advocated for preventing LVDD in type 2 diabetes.

Subclinical left ventricular diastolic dysfunction and incident type 2 diabetes risk: the Korean Genome and Epidemiology Study

Background

Subclinical left ventricular (LV) diastolic dysfunction in type 2 diabetes (T2D) is a common finding and represents an early sign of diabetic cardiomyopathy. However, the relationship between LV diastolic dysfunction and the incident T2D has not been previously studied.

Methods

A total of 1817 non-diabetic participants (mean age, 54 years; 48% men) from the Korean Genome and Epidemiology Study who were free of cardiovascular disease were studied. LV structure and function were assessed by conventional echocardiography and tissue Doppler imaging. Subclinical LV diastolic dysfunction was defined using age-specific cutoff limits for early diastolic (Em) velocity, mitral E/Em ratio, and left atrial volume index.

Results

During the 6-year follow-up period, 273 participants (15%) developed T2D. Participants with incident T2D had greater LV mass index (86.7 ± 16.4 vs. 91.2 ± 17.0 g/m²), worse diastolic function, reflected by lower Em velocity (7.67 ± 1.80 vs. 7.47 ± 1.70) and higher E/Em ratio (9.19 ± 2.55 vs. 10.23 ± 3.00), and higher prevalence of LV diastolic dysfunction (34.6 vs. 54.2%), compared with those who did not develop T2D (all P < 0.001). In a multivariate logistic regression model, lower Em velocity (odd ratio [OR], 0.867; 95% confidence interval [CI] 0.786–0.957) and the presence of LV diastolic dysfunction (OR, 1.617; 95% CI 1.191–2.196) were associated with the development of T2D, after adjusting for potential confounding factors.

Conclusions

In a community-based cohort, the presence of subclinical LV diastolic dysfunction was a predictor of the progression to T2D. These data suggest that the echocardiographic assessment of LV diastolic function may be helpful in identifying non-diabetic subjects at risk of incident T2D.

Abnormal echocardiography in patients with type 2 diabetes and relation to symptoms and clinical characteristics

OBJECTIVES

We aimed to determine the prevalence of echocardiographic abnormalities and their relation to clinical characteristics and cardiac symptoms in a large, contemporary cohort of patients with type 2 diabetes.

RESULTS

A total of 1030 patients with type 2 diabetes participated. Echocardiographic abnormalities were present in 513 (49.8%) patients, mainly driven by a high prevalence of diastolic dysfunction 178 (19.4%), left ventricular hypertrophy 213 (21.0%) and left atrial enlargement, 200 (19.6%). The prevalence increased markedly with age from 31.1% in the youngest group (<55 years) to 73.9% in the oldest group (>75 years) (p < 0.001) and was equally distributed among the sexes (p = 0.76). In univariate analyses, electrocardiographic abnormalities, age, body mass index, known coronary heart disease, hypertension, albuminuria, diabetes duration and creatinine were associated with abnormal echocardiography along with dyspnoea and characteristic chest pain (p < 0.05 for all). Neither of the cardiac symptoms nor clinical characteristics had sufficient sensitivity and specificity to accurately identify patients with abnormal echocardiography.

CONCLUSION

Echocardiographic abnormalities are very common in outpatients with type 2 diabetes, but neither cardiac symptoms nor clinical characteristics are effective to identify patients with echocardiographic abnormalities.

Evaluation of left and right ventricular functions using conventional and tissue Doppler echocardiography in children with type 1 diabetes mellitus

BACKGROUND

The aim of the study was the evaluation of the effects of glycemic control in children and adolescents with type 1 diabetes on cardiac functions.

METHODS

Diabetic patients were divided into two groups as well-controlled and poorly controlled patients. All patients underwent M-mode, two-dimensions (2D), pulsed wave (PW) Doppler, and tissue Doppler (TDI) echocardiography to evaluate systolic and diastolic functions.

RESULTS

Early diastolic mitral flow velocity (Em) and the ratio of early to late diastolic mitral flow velocity (Em/Am) obtained with TDI were found to be significantly lower in the well-controlled then the control group and significantly lower in the poorly-controlled group than the well-controlled group. Am, isovolumetric relaxation time (IVRT) and myocardial performance index (MPI) were significantly higher in the poorly controlled group. The ratio of early mitral diastolic flow velocity obtained with PW Doppler (E) to Em (E/Em) was significantly higher in the diabetic group. According to the mitral valve PW Doppler results, 13.6% of the well-controlled group and 31% of the poorly-controlled group had type 1 diastolic dysfunction. According to the mitral TDI results, 18% of the well-controlled group and 40.4% of poorly-controlled group had type 1 diastolic dysfunction.

CONCLUSIONS

Conventional and TDI echocardiography revealed impairment in left ventricular functions in some patients. Tissue Doppler echocardiography also revealed diastolic impairment in some patients who appeared normal with PW Doppler echocardiography. The present study found that impairment in left ventricular diastolic functions is directly related to glycemic control and the rate of diabetic cardiomyopathy was higher in children with poor metabolic control.

Myocardial dysfunction and cardiovascular disease in type 2 diabetes

Type 2 diabetes mellitus (T2DM) is strongly associated with increased risk of myocardial dysfunction and cardiovascular disease (CVD), two separate conditions which often co-exist and influence each other's course. The prevalence of myocardial dysfunction may be as high as 75% in T2DM populations but is often overlooked due to the initial asymptomatic nature of the disease, complicating co-morbidities such as coronary artery disease (CAD) and obesity, and the lack of consensus on diagnostic criteria. More sensitive echocardiographic applications are furthermore needed to improve detection of early subclinical changes in myocardial function which do not affect conventional echocardiographic parameters. The pathophysiology of the diabetic myocardial dysfunction is not fully elucidated, but involves hyperglycemia and high levels of free fatty acids. It evolves over several years and increases the risk of developing overt HF, and is suggested to at least in part account for the worse outcome seen in T2DM individuals after cardiac events. CAD and stroke are the most frequent CV manifestations among T2DM patients and relate to a large degree to the accelerated atherosclerosis driven by inflammation. Diagnosing CAD is challenging due to the lower sensitivity inherent in the diagnostic tests and there is thus a need for new biomarkers to improve prediction and detection of CAD. It seems that a multi-factorial approach (i.e. targeting several CV risk factors simultaneously) is superior to a strict glucose lowering strategy in reducing risk for macrovascular events, and recent research may even support an effect also on HF outcomes.

New Molecular Insights of Insulin in Diabetic Cardiomyopathy

Type 2 diabetes mellitus (T2DM) is a highly prevalent disease worldwide. Cardiovascular disorders generated as a consequence of T2DM are a major cause of death related to this disease. Diabetic cardiomyopathy (DCM) is characterized by the morphological, functional and metabolic changes in the heart produced as a complication of T2DM. This cardiac disorder is characterized by constant high blood glucose and lipids levels which eventually generate oxidative stress, defective calcium handling, altered mitochondrial function, inflammation and fibrosis. In this context, insulin is of paramount importance for cardiac contractility, growth and metabolism and therefore, an impaired insulin signaling plays a critical role in the DCM development. However, the exact pathophysiological mechanisms leading to DCM are still a matter of study. Despite the numerous questions raised in the study of DCM, there have also been important findings, such as the role of micro-RNAs (miRNAs), which can not only have the potential of being important biomarkers, but also therapeutic targets. Furthermore, exosomes also arise as an interesting variable to consider, since they represent an important inter-cellular communication mechanism and therefore, they may explain many aspects of the pathophysiology of DCM and their study may lead to the development of therapeutic agents capable of improving insulin signaling. In addition, adenosine and adenosine receptors (ARs) may also play an important role in DCM. Moreover, the possible cross-talk between insulin and ARs may provide new strategies to reverse its defective signaling in the diabetic heart. This review focuses on DCM, the role of insulin in this pathology and the discussion of new molecular insights which may help to understand its underlying mechanisms and generate possible new therapeutic strategies.