The E/e' ratio difference between subjects with type 2 diabetes and controls. A meta-analysis of clinical studies

Sympathetic Neural Overdrive, Aortic Stiffening, Endothelial Dysfunction, and Impaired Exercise Capacity in Severe COVID-19 Survivors: A Mid-Term Study of Cardiovascular Sequelae

BACKGROUND

COVID-19 has become a dramatic health problem during this century. In addition to high mortality rate, COVID-19 survivors are at increased risk for cardiovascular diseases 1-year after infection. Explanations for these manifestations are still unclear but can involve a constellation of biological alterations. We hypothesized that COVID-19 survivors compared with controls exhibit sympathetic overdrive, vascular dysfunction, cardiac morpho-functional changes, impaired exercise capacity, and increased oxidative stress.

METHODS

Nineteen severe COVID-19 survivors and 19 well-matched controls completed the study. Muscle sympathetic nerve activity (microneurography), brachial artery flow-mediated dilation and blood flow (Doppler-Ultrasound), carotid-femoral pulse wave velocity (Complior), cardiac morpho-functional parameters (echocardiography), peak oxygen uptake (cardiopulmonary exercise testing), and oxidative stress were measured ~3 months after hospital discharge. Complementary experiments were conducted on human umbilical vein endothelial cells cultured with plasma samples from subjects.

RESULTS

Muscle sympathetic nerve activity and carotid-femoral pulse wave velocity were greater and brachial artery flow-mediated dilation, brachial artery blood flow, E/e' ratio, and peak oxygen uptake were lower in COVID-19 survivors than in controls. COVID-19 survivors had lower circulating antioxidant markers compared with controls, but there were no differences in plasma-treated human umbilical vein endothelial cells nitric oxide production and reactive oxygen species bioactivity. Diminished peak oxygen uptake was associated with sympathetic overdrive, vascular dysfunction, and reduced diastolic function in COVID-19 survivors.

CONCLUSIONS

Our study revealed that COVID-19 survivors have sympathetic overactivation, vascular dysfunction, cardiac morpho-functional changes, and reduced exercise capacity. These findings indicate the need for further investigation to determine whether these manifestations are persistent longer-term and their impact on the cardiovascular health of COVID-19 survivors.

A high-sucrose diet exacerbates the left ventricular phenotype in a high fat-fed streptozotocin rat model of diabetic cardiomyopathy

Left ventricular (LV) dysfunction is an early, clinically detectable sign of cardiomyopathy in type 2 diabetes mellitus (T2DM) that precedes the development of symptomatic heart failure. Preclinical models of diabetic cardiomyopathy are essential to develop therapies that may prevent or delay the progression of heart failure. This study examined the molecular, structural, and functional cardiac phenotype of two rat models of T2DM induced by a high-fat diet (HFD) with a moderate- or high-sucrose content (containing 88.9 or 346 g/kg sucrose, respectively), plus administration of low-dose streptozotocin (STZ). At 8 wk of age, male Sprague-Dawley rats commenced a moderate- or high-sucrose HFD. Two weeks later, rats received low-dose STZ (35 mg/kg ip for 2 days) and remained on their respective diets. LV function was assessed by echocardiography 1 wk before end point. At 22 wk of age, blood and tissues were collected postmortem. Relative to chow-fed sham rats, diabetic rats on a moderate- or high-sucrose HFD displayed cardiac reactive oxygen species dysregulation, perivascular fibrosis, and impaired LV diastolic function. The diabetes-induced impact on LV adverse remodeling and diastolic dysfunction was more apparent when a high-sucrose HFD was superimposed on STZ. In conclusion, a high-sucrose HFD in combination with low-dose STZ produced a cardiac phenotype that more closely resembled T2DM-induced cardiomyopathy than STZ diabetic rats subjected to a moderate-sucrose HFD.NEW & NOTEWORTHY Left ventricular dysfunction and adverse remodeling were more pronounced in diabetic rats that received low-dose streptozotocin (STZ) and a high-sucrose high-fat diet (HFD) compared with those on a moderate-sucrose HFD in combination with STZ. Our findings highlight the importance of sucrose content in diet composition, particularly in preclinical studies of diabetic cardiomyopathy, and demonstrate that low-dose STZ combined with a high-sucrose HFD is an appropriate rodent model of cardiomyopathy in type 2 diabetes.

Glycemic Markers and Heart Failure Subtypes: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND

Although diabetes increases heart failure (HF) risk, it is unclear how various dysglycemia markers (hemoglobin A1C [HbA1C], fasting plasma glucose [FPG], homeostasis model assessment of insulin resistance, and fasting insulin) are associated with HF subtypes (HF with preserved ejection fraction [HFpEF] and HF with reduced ejection fraction [HFrEF]). We assessed the relation of markers of dysglycemia and risks of HFpEF and HFrEF.

METHODS AND RESULTS

We included 6688 adults without prevalent cardiovascular disease who attended the first MESA visit (2000-2002) and were followed for incident hospitalized HF (HFpEF or HFrEF). Association of glycemic markers and status (normoglycemia, prediabetes, diabetes) with HFpEF and HFrEF were evaluated using adjusted Cox models. Over a median follow-up of 14.9 years, there were 356 HF events (145 HFpEF, 173 HFrEF, and 38 indeterminate HF events). Diabetes status conferred higher risks of HFpEF (hazard ratio [HR] 1.85, 95% confidence interval [CI] 1.57-2.68) and HFrEF (HR 2.02, 95% CI 1.38-2.97) compared with normoglycemia. Higher levels of FPG (≥126 mg/dL) and HbA1C (≥6.5%) were associated with similarly higher risks of HFpEF (HR for FPG 1.96, 95% CI 1.21-3.17; HR for HbA1C 2.00, 95% CI 1.20-3.31) and HFrEF (HR for FPG 1.84, 95% CI 1.18-2.88; HR for HbA1C 1.99, 95% CI 1.28-3.09) compared with reference values. Prediabetic range HbA1C (5.7%-6.4%) or FPG (100%-125 mg/dL), homeostasis model assessment of insulin resistance, and fasting insulin were not significantly associated with HFpEF or HFrEF.

CONCLUSIONS

Among community-dwelling individuals, HbA1C and FPG in the diabetes range were each associated with higher risks of HFpEF and HFrEF, with similar magnitudes of their associations.

LAY ABSTRACT

Heart failure (HF) has 2 major subtypes (the heart's inability to pump or to fill up). Diabetes is known to increase HF risk, but its effects and that of markers of high glucose levels (fasting blood glucose and hemoglobin A1C) on the occurrence of HF subtypes remains unknown. Among 6688 adults without known cardiovascular disease followed for nearly 15 years, diabetes conferred significantly higher risks of both HF types, compared with those with normal blood glucose levels. Higher levels of fasting blood glucose and hemoglobin A1C were similarly associated with higher risks of both types of HF.

Fetal echocardiographic evaluation before and after nifedipine treatment in preterm labor

OBJECTIVE

To assess the effect of nifedipine used for tocolysis on cardiac morphology and functions.

METHODS

The study included 47 pregnant women diagnosed with preterm labor at 32-33 weeks. Fetal echocardiographic evaluation was performed with two-dimensional (2D) imaging, M-mode, pulsed wave (PW) Doppler, and tissue Doppler imaging (TDI) before and after the 48^th hour of nifedipine treatment.

RESULTS

No significant change was observed in Doppler parameters (pulsatility indices of the umbilical artery, middle cerebral artery, ductus venosus) and cardiac morphology (cardiothoracic ratio, end-diastolic longitudinal diameters, sphericity indices, wall thickness) after nifedipine treatment. The parameters obtained with TDI (e', a', s', e'/a', E/e' of mitral and tricuspid valves), M- mode (TAPSE, MAPSE), pulsed Doppler (myocardial performance index, left cardiac output, right cardiac output, tricuspid E, A waves, tricuspid E/A ratio, mitral E, A waves, mitral E/A ratio) did not change after nifedipine treatment.

CONCLUSION

To date, this is the first study to examine the effects of nifedipine on the fetal heart using the TDI. Since nifedipine is a drug that is frequently used and well-tolerated in the prevention of preterm labor, it is crucial that it does not cause changes in fetal cardiac parameters during tocolysis. Therefore, we used TDI in addition to conventional methods to evaluate the effect of nifedipine, which is frequently used in obstetrics, on cardiac functions in the early period. Nifedipine treatment seems not to affect systolic or diastolic functions. This indicates that nifedipine is reliable on cardiac functions and morphology in pregnancies treated for preterm labor.

Multi-dimensional characterization of prediabetes in the Project Baseline Health Study

Background

We examined multi-dimensional clinical and laboratory data in participants with normoglycemia, prediabetes, and diabetes to identify characteristics of prediabetes and predictors of progression from prediabetes to diabetes or reversion to no diabetes.

Methods

The Project Baseline Health Study (PBHS) is a multi-site prospective cohort study of 2502 adults that conducted deep clinical phenotyping through imaging, laboratory tests, clinical assessments, medical history, personal devices, and surveys. Participants were classified by diabetes status (diabetes [DM], prediabetes [preDM], or no diabetes [noDM]) at each visit based on glucose, HbA1c, medications, and self-report. Principal component analysis (PCA) was performed to create factors that were compared across groups cross-sectionally using linear models. Logistic regression was used to identify factors associated with progression from preDM to DM and for reversion from preDM to noDM.

Results

At enrollment, 1605 participants had noDM; 544 had preDM; and 352 had DM. Over 4 years of follow-up, 52 participants with preDM developed DM and 153 participants reverted to noDM. PCA identified 33 factors composed of clusters of clinical variables; these were tested along with eight individual variables identified a priori as being of interest. Six PCA factors and six a priori variables significantly differed between noDM and both preDM and DM after false discovery rate adjustment for multiple comparisons (q < 0.05). Of these, two factors (one comprising glucose measures and one of anthropometry and physical function) demonstrated monotonic/graded relationships across the groups, as did three a priori variables: ASCVD risk, coronary artery calcium, and triglycerides (q < 10^–21 for all). Four factors were significantly different between preDM and noDM, but concordant or similar between DM and preDM: red blood cell indices (q = 8 × 10^-10), lung function (q = 2 × 10^-6), risks of chronic diseases (q = 7 × 10^-4), and cardiac function (q = 0.001), along with a priori variables of diastolic function (q = 1 × 10^-10), sleep efficiency (q = 9 × 10^-6) and sleep time (q = 6 × 10^-5). Two factors were associated with progression from prediabetes to DM: anthropometry and physical function (OR [95% CI]: 0.6 [0.5, 0.9], q = 0.04), and heart failure and c-reactive protein (OR [95% CI]: 1.4 [1.1, 1.7], q = 0.02). The anthropometry and physical function factor was also associated with reversion from prediabetes to noDM: (OR [95% CI]: 1.9 [1.4, 2.7], q = 0.02) along with a factor of white blood cell indices (OR [95% CI]: 0.6 [0.4, 0.8], q = 0.02), and the a priori variables ASCVD risk score (OR [95% CI]: 0.7 [0.6, 0.9] for each 0.1 increase in ASCVD score, q = 0.02) and triglycerides (OR [95% CI]: 0.9 [0.8, 1.0] for each 25 mg/dl increase, q = 0.05).

Conclusions

PBHS participants with preDM demonstrated pathophysiologic changes in cardiac, pulmonary, and hematology measures and declines in physical function and sleep measures that precede DM; some changes predicted an increased risk of progression to DM. A factor with measures of anthropometry and physical function was the most important factor associated with progression to DM and reversion to noDM. Future studies may determine whether these changes elucidate pathways of progression to DM and related complications and whether they can be used to identify individuals at higher risk of progression to DM for targeted preventive interventions.

Trial registration ClinicalTrials.gov NCT03154346

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01565-x.

Clinical and echocardiographic characteristics in patients with heart failure and type 2 diabetes

Objective: The coexistence of type 2 diabetes (T2D) and heart failure (HF) has obvious consequences during cardiovascular diagnosis. This study evaluated the relationship between T2D and clinical and echocardiographic features of patients with HF. Methods & results: 121 patients with HF were clinically evaluated by echocardiography in this case-control study. They were divided into two groups based on the presence of T2D. Patients with diabetes were subdivided and compared via an HbA1c control. Significant differences between T2D and non-T2D groups were detected by comparing the left atrial diameter, E/E' and left ventricular end-diastolic diameter. When comparing patients with diabetes, differences in acute heart failure episodes, left ventricular ejection fraction, left atrial diameter and E/E' were evaluated. Conclusion: T2D was associated with important cardiac alterations and more severe HF. Poor control of diabetes resulted in worse cardiovascular outcomes.

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.

Suppression of Inflammatory Cardiac Cytokine Network in Rats with Untreated Obesity and Pre-Diabetes by AT2 Receptor Agonist NP-6A4

Obesity affects over 42% of the United States population and exacerbates heart disease, the leading cause of death in men and women. Obesity also increases pro-inflammatory cytokines that cause chronic tissue damage to vital organs. The standard-of-care does not sufficiently attenuate these inflammatory sequelae. Angiotensin II receptor AT2R is an anti-inflammatory and cardiovascular protective molecule; however, AT2R agonists are not used in the clinic to treat heart disease. NP-6A4 is a new AT2R peptide agonist with an FDA orphan drug designation for pediatric cardiomyopathy. NP-6A4 increases AT2R expression (mRNA and protein) and nitric oxide generation in human cardiovascular cells. AT2R-antagonist PD123319 and AT2RSiRNA suppress NP-6A4-effects indicating that NP-6A4 acts through AT2R. To determine whether NP-6A4 would mitigate cardiac damage from chronic inflammation induced by untreated obesity, we investigated the effects of 2-weeks NP-6A4 treatment (1.8 mg/kg delivered subcutaneously) on cardiac pathology of male Zucker obese (ZO) rats that display obesity, pre-diabetes and cardiac dysfunction. NP-6A4 attenuated cardiac diastolic and systolic dysfunction, cardiac fibrosis and cardiomyocyte hypertrophy, but increased myocardial capillary density. NP-6A4 treatment suppressed tubulointerstitial injury marker urinary β-NAG, and liver injury marker alkaline phosphatase in serum. These protective effects of NP-6A4 occurred in the presence of obesity, hyperinsulinemia, hyperglycemia, and hyperlipidemia, and without modulating blood pressure. NP-6A4 increased expression of AT2R (consistent with human cells) and cardioprotective erythropoietin (EPO) and Notch1 in ZO rat heart, but suppressed nineteen inflammatory cytokines. Cardiac miRNA profiling and in silico analysis showed that NP-6A4 activated a unique miRNA network that may regulate expression of AT2R, EPO, Notch1 and inflammatory cytokines, and mitigate cardiac pathology. Seventeen pro-inflammatory and pro-fibrotic cytokines that increase during lethal cytokine storms caused by infections such as COVID-19 were among the cytokines suppressed by NP-6A4 treatment in ZO rat heart. Thus, NP-6A4 activates a novel anti-inflammatory network comprised of 21 proteins in the heart that was not reported previously. Since NP-6A4's unique mode of action suppresses pro-inflammatory cytokine network and attenuates myocardial damage, it can be an ideal adjuvant drug with other anti-glycemic, anti-hypertensive, standard-of-care drugs to protect the heart tissues from pro-inflammatory and pro-fibrotic cytokine attack induced by obesity.

Correlation between albuminuria and tissue Doppler-derived left ventricular myocardial performance index in patients with type 2 diabetes

BACKGROUND

Albuminuria is considered as a significant predictor of cardiovascular morbidity and mortality in patients with diabetes mellitus. The main purpose of this study was to determine the correlation between albuminuria and global left ventricular (LV) function in patients with type 2 diabetes (T2D).

METHODS

This observational study was conducted on 80 consecutive asymptomatic patients with T2D and an LV ejection fraction ≥55%. The patients were divided into two groups depending on the presence or absence of albuminuria. Echocardiography-derived indices of the LV function were then compared between these groups.

RESULTS

The patients with albuminuria were older (mean ± SD: 60.37 ± 9.05 vs 54.52 ± 10.26 years of age, P = .01) and had higher hemoglobin A1c (HbA1c) levels (8.45 ± 1.97 vs 7.25 ± 1.93 mg/dL, P = .012) than those without albuminuria. Among the echocardiographic variables, the patients with albuminuria had higher LV Tei-index (median [lower-upper quartile]: 0.620 [0.455-0.824] vs 0.441 [0.336-0.586], P < .001), more prolonged early filling (E)-wave deceleration time (274.87 ± 75.97 vs 239.40 ± 61.35 ms, P = .032), increased interventricular septal wall thickness (1.11 ± 0.31 vs 0.95 ± 0.21 cm, P = .012), and lower mean early diastolic mitral annular velocity (7.57 ± 2.34 vs 8.68 ± 2.46 cm/s, P = .046) than those without albuminuria. Among risk factors, only albuminuria and HbA1c levels were associated with a significant increase in LV Tei-index (Beta = 0.426 and P < .001, Beta = 0.226 and P = .042, respectively).

CONCLUSION

The LV Tei-index was significantly higher in diabetic patients with than without albuminuria. Low HbA1c levels were correlated with a decrease in LV Tei-index.

Left Ventricular Diastolic Dysfunction in Type 2 Diabetes-Progress and Perspectives

In-depth understanding of early cardiovascular manifestations in diabetes is high on international research and prevention agendas given that cardiovascular events are the leading cause of death for diabetic patients. Our aim was to review recent developments in the echocardiographic assessment of left ventricular diastolic dysfunction (LVDD) as a telltale pre-clinical disturbance preceding diabetic cardiomyopathy. We analyzed papers in which patients had been comprehensively assessed echocardiographically according to the latest LVDD guidelines (2016), and those affording comparisons with previous, widely used recommendations (2009). We found that the updated algorithm for LVDD is more effective in predicting adverse cardiovascular events in patients with established LVDD, and less specific in grading other patients (labelled "indeterminate"). This may prove instrumental for recruiting "indeterminate" LVDD cases among patients with type 2 diabetes mellitus (T2DM) in future screening programs. As an interesting consideration, the elevated values of the index E/e' can point to early diastolic impairment, foretelling diabetic cardiomyopathy. Identifying subclinical signs early makes clinical sense, but the complex nature of T2DM calls for further research. Specifically, longitudinal studies on rigorously selected cohorts of diabetic patients are needed to better understand and predict the subtle, slow onset of cardiac manifestations with T2DM as a complicating backdrop.