Incidence and prognostic implication of unrecognized myocardial scar characterized by cardiac magnetic resonance in diabetic patients without clinical evidence of myocardial infarction

Oral edaravone ameliorates myocardial fibrosis in type 2 diabetic rats by TGF-β1/Smad signaling pathway

Myocardial fibrosis, characterized by increased reactive oxygen species (ROS), is a key pathological feature of diabetic cardiomyopathy (DCM). Although oral edaravone (EDA) shows therapeutic potential in ameliorating myocardial fibrosis in DCM, the precise mechanisms remain unclear. Transcriptome analysis of myocardial tissues revealed a dramatic up-regulation of the TGF-β1/Smad pathway, which was reversed by oral EDA treatment. In vitro studies showed that oral EDA attenuated myocardial fibrosis by inhibiting the TGF-β1/Smad signaling pathway and its downstream fibrosis key factors, Col3a1 and α-SMA. These findings suggest that oral EDA improves myocardial fibrosis in Type 2 diabetes mellitus (T2DM) by inhibiting the TGF-β1/Smad signaling pathway and holds promise as an effective treatment for myocardial fibrosis in DCM.

Evaluation of the prognostic value of lateral MAPSE in patients with suspected coronary artery disease

Objectives

To evaluate the prognostic value of lateral mitral annular plane systolic excursion (MAPSE) in the prediction of major adverse cardiology events (MACE) in patients with suspected coronary artery disease (CAD).

Methods

233 consecutive patients were enrolled with suspected CAD from October 2012 to September 2013 and performed contrast-enhanced cardiac magnetic resonance (CMR) and two-dimensional echocardiogram studies no later than 72 h after admission. CMR imaging protocol included 4-chamber cine(cine-CMR), cardiovascular magnetic resonance angiography (CMRA) and late gadolinium enhancement (LGE). The primary endpoint is the time of first occurrence of a MACE The independent association between lateral MAPSE and MACE was evaluated by Kaplan-Meier analysis and multivariable Cox regression analysis. C statistic and net reclassification improvement (NRI) were used to evaluate the prognostic value of lateral MAPSE in MACE.

Results

Forty-five MACE occurred during an average follow-up of 9.2 years. Patients with lateral MAPSE＜9.885 mm experienced a significantly higher incidence of MACE than patients with lateral MAPSE ≥ 9.885 mm (P＜0.001). After adjustment for established univariate predictors (age, diabetes, hypertension, hypercholesterolemia, transmural myocardial infarction), lateral MAPSE remained a significant independent predictor of MACE (HR = 1.373; P = 0.020). The incorporation of lateral MAPSE into the risk model resulted in significant improvement in C statistic (increasing from 0.668 to 0.844; P = 0.005). NRI improvement was 0.33 (P＜0.001).

Conclusions

lateral MAPSE derived from cine-CMR is an independent predictor of MACE, and improve risk reclassification beyond traditional clinical and CMR risk factors in patients with suspected coronary disease.

Tinglu Yixin granule inhibited fibroblast-myofibroblast transdifferentiation to ameliorate myocardial fibrosis in diabetic mice

ETHNOPHARMACOLOGICAL RELEVANCE

Myocardial fibrosis is one of the pathological characteristics of advanced diabetic cardiomyopathy (DCM) and serves as the strong evidence of poor prognosis. Among them, the transdifferentiation of cardiac fibroblasts (CFs) may play a crucial role in the development of myocardial fibrosis in DCM. Tinglu Yixin granule (TLYXG) has been clinically used for many years and can significantly improve cardiac function of patients with DCM. However, the effect of TLYXG on myocardial fibrosis in DCM remains unknown, and the underlying mechanisms of its efficacy have yet to be fully understood.

AIM OF THE STUDY

This study aimed to investigate the impact and underlying mechanism of TLYXG on myocardial fibrosis in diabetes mice.

MATERIALS AND METHODS

The bioactive compounds in TLYXG were identified using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). The potential mechanism of TLYXG in treating DCM was predicted using network pharmacology combined with molecular docking and protein-protein docking. The mice model of type 2 diabetes were established by intraperitoneal injection of streptozotocin (STZ) and the high-fat diet (HFD). Indicators of pancreatic islet function, lipids, oxidative stress, and inflammatory factors were tested using kits. Cardiac function was assessed in diabetic mice using echocardiography. Histologic staining was performed to evaluate myocardial hypertrophy and fibrosis. Mechanistically, the hypothesis was tested through rescue experiments. The expression levels of transient receptor potential channel 6 (TRPC6), transforming growth factor-β1 (TGF-β1), collagen I (COL-I) and alpha-smooth muscle actin (α-SMA), along with the mRNA and phosphorylation levels of SMAD family member 3 (Smad3) and protein 38 mitogen-activated protein kinase (p38 MAPK), were assessed using quantitative RT-qPCR, Western blot, immunohistochemistry, and immunofluorescence. Neonatal lactating mice were used to extract primary CFs for vitro experiments. Scratch and transwell assays were conducted to assess CFs migration and invasion abilities. Western blot and immunofluorescence were used to evaluate the expression levels of CFs transdifferentiation markers COL-I and α-SMA.

RESULTS

A total of 168 active ingredients were detected in TLYXG based on UPLC-MS and databases. Network pharmacology indicated that TLYXG could improve DCM through inflammatory mediator regulation of TRP channels, TGF-beta signaling pathway, and MAPK signaling pathway. ELISA results showed that TLYXG could ameliorate metabolic levels, inflammation, and oxidative stress in diabetic mice. Echocardiography suggested that TLYXG improved cardiac systolic and diastolic dysfunction in diabetic mice. Histological analysis revealed that TLYXG alleviated myocardial fibrosis in diabetes mice. Additionally, molecular docking analysis indicated strong binding activity between the main active ingredients of TLYXG and TRPC6 of the TRP family. At the molecular level, TLYXG reduced the mRNA and protein expression levels of TRPC6 and TGF-β1 and inhibited the mRNA and phosphorylation levels of Smad3 and p38 MAPK. Furthermore, TLYXG inhibited CFs migration and invasion, and reduced the expression levels of the CFs transdifferentiation markers COL-I and α-SMA.

CONCLUSION

TLYXG inhibited the proliferation, migration, invasion and transdifferentiation of CFs by suppressing TGF-β1/Smad3/p38 MAPK signaling through down-regulation of TRPC6, thereby ameliorating myocardial fibrosis in diabetes mice.

Assessment of unrecognized myocardial infarction using cardiac magnetic resonance imaging in patients with endstage renal disease

Objective

To assess the frequency of unrecognized myocardial infarction and identify additional ischemic conditions, as well as to evaluate the efficacy of cardiac magnetic resonance imaging (CMRI) in risk groups, comparing the imaging findings with electro-cardiographic (ECG) and laboratory data in patients with stage 5 chronic kidney disease, also known as end-stage renal disease.

Materials and Methods

This was a prospective single-center study involving 20 patients who were referred to our radiology department to undergo CMRI between June 2010 and December 2011. Resting left ventricular functions and (early and late) myocardial contrast enhancement were assessed in all patients. Laboratory tests and ECG were conducted on all individuals. The mean duration of clinical follow-up was 18 á 4 months.

Results

Pathological results were seen in six (30%) of the patients in our study sample. Scar tissue was identified as a high-risk factor in three patients (15%), and myocardial hibernation was shown to pose a moderate risk in three patients (15%). In the remaining 14 cases, no pathology was identified, and the risk was therefore categorized as low. A statistically significant disparity in mortality rates was observed between the high- and low-risk groups (p < 0.05). There were no statistically significant differences between the two groups in terms of the ECG and cardiac biomarkers.

Conclusion

Our findings indicate that CMRI is effective in accurately categorizing risk groups and detecting ischemic conditions, even when such events are not evident on ECG or laboratory tests.

Unravelling the cardio-renal-metabolic-foot connection in people with diabetes-related foot ulceration: a narrative review

Diabetes-related foot ulceration (DFU), a serious but preventable complication of diabetes, is a leading cause of hospitalisation, lower extremity amputation and disability worldwide. People with DFU have a greater burden of cardiovascular risk factors, heart failure and chronic kidney disease, resulting in over two-fold higher risk of cardiovascular death compared with people with diabetes without DFU. Here, we propose a "cardio-renal-metabolic-foot" connection in people with diabetes based on shared pathophysiological mechanisms linking DFU with cardiovascular and renal disease. Whilst these mechanistic links remain to be fully elucidated, systemic inflammation and infection in the context of DFU are postulated as key mediators in the development, and progression of, cardiovascular and renal disease. However, cardiovascular and renal disease are also implicated in the pathogenesis of DFU, highlighting the multi-directional interplay between conditions. The impact of screening, prevention, and early management of cardiovascular complications associated with DFU requires further research. Multi-modality cardiac imaging could play a role in unravelling disease mechanisms leading to novel therapeutic strategies, as well as facilitating personalised risk assessment and management. Recent clinical trials have transformed the therapeutic landscape for people with type 2 diabetes, by demonstrating that sodium glucose co-transporter 2 inhibitors, glucagon-like peptide-1 agonists and non-steroidal mineralocorticoid receptor antagonists improve cardiovascular and renal outcomes. Although dedicated research in people with DFU is warranted, these therapies could target multiple facets of the "cardio-renal-metabolic-foot" connection. The holistic, person-centred approach to managing DFU should incorporate new multidisciplinary models of care focusing on the prevention and management of cardiovascular and kidney disease.

Outcomes of Coronary Artery Bypass Grafting in Patients With Impaired Left Ventricular Function and the Role of Preoperative Myocardial Viability

Background Coronary artery bypass grafting (CABG) improves outcomes in patients with ischemic left ventricular (LV) dysfunction, but accurate patient selection remains critical. Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging aids in assessing myocardial viability, a key predictor of surgical outcomes. This study aimed to evaluate the impact of myocardial viability on postoperative outcomes in patients undergoing CABG. Methods This was a single-center prospective analysis of clinical outcomes in 37 patients with impaired LV function (mean ejection fraction: 35.59%); myocardial viability was assessed using LGE-CMR prior to CABG. Patient demographics, perioperative details, and short-term outcomes, including in-hospital mortality and recovery metrics, were analyzed. Results Patients exhibited high myocardial viability (mean: 88.16%), with an average of 2.35 non-viable segments. In-hospital mortality was 5.4% (n=2), and the mean hospital stay was six days. Patients with greater viability demonstrated better recovery and fewer complications. Multivessel coronary artery disease was prevalent (94.6%, n=35), with tailored graft configurations addressing individual anatomical and disease complexities. Conclusion LGE-CMR is a valuable tool for predicting outcomes in ischemic LV dysfunction. Myocardial viability strongly correlates with improved surgical recovery, highlighting the importance of integrating LGE-CMR into preoperative decision-making. Further studies are required to explore the long-term impact of myocardial viability on treatment outcomes and quality of life.

Coronary Microvascular Dysfunction and Diffuse Myocardial Fibrosis in Patients With Type 2 Diabetes Using Quantitative Perfusion MRI

BACKGROUND

Imaging techniques that quantitatively and automatically measure changes in the myocardial microcirculation in patients with diabetes are lacking.

PURPOSE

To detect diabetic myocardial microvascular complications using a novel automatic quantitative perfusion MRI technique, and to explore the relationship between myocardial microcirculation dysfunction and fibrosis.

STUDY TYPE

Prospective.

SUBJECTS

101 patients with type 2 diabetes mellitus (T2DM) (53 without and 48 with complications), 20 healthy volunteers.

FIELD STRENGTH/SEQUENCE

3.0T; modified Look-Locker inversion-recovery sequence; saturation recovery sequence and dual-bolus technique; segmented fast low-angle shot sequence.

ASSESSMENT

All participants underwent MRI to determine the rest myocardial blood flow (MBF), stress MBF, myocardial perfusion reserve (MPR), and extracellular volume (ECV), which represents the extent of myocardial fibrosis.

STATISTICAL TESTS

Kolmogorov-Smirnov test, Shapiro-Wilk test, Kruskal-Wallis H test, Mann-Whitney U test, chi-square test, Spearman correlation coefficient, multivariable linear regression analysis. P < 0.05 was considered statistically significant.

RESULTS

The rest MBF was not significantly different between the T2DM without complications group (1.1, IQR: 0.9-1.3) and the control group (1.1, 1.0-1.3) (P = 1.000), but it was significantly lower in the T2DM with complications group (0.8, 0.6-1.0) than in both other groups. The stress MBF and MPR were significantly lower in the T2DM without complications group (1.9, 1.5-2.3, and 1.7, 1.4-2.1, respectively) than in the control group (3.0, 2.6-3.5, and 2.7, 2.4-3.1, respectively), and were also significantly lower in the T2DM with complications group (1.1, 0.9-1.4, and 1.4, 1.2-1.8, respectively) than in the T2DM without complications group. A decrease in MBF and MPR were significantly associated with an increase in the ECV.

DATA CONCLUSION

Quantitative perfusion MRI can evaluate myocardial microcirculation dysfunction. In T2DM, there was a significant decrease in both MBF and MPR compared to healthy controls, with the decrease being significantly different between T2DM with and without complications groups. The decrease of MBF was significantly associated with the development of myocardial fibrosis, as determined by ECV.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.

Prognostic value of stress perfusion cardiac magnetic resonance in patients with prediabetes and suspected coronary artery disease

BACKGROUND

Stress perfusion cardiac magnetic resonance (CMR) is an accurate and comprehensive modality for evaluating patients with suspected coronary artery disease (CAD), but its prognostic value in prediabetic patients is uncertain.

METHODS

This retrospective study included 452 consecutive prediabetic patients without prior diagnoses of CAD who underwent adenosine stress perfusion CMR. The primary endpoint was major adverse cardiovascular events (MACE), defined as cardiovascular death, nonfatal myocardial infarction (MI), hospitalization for heart failure, ischemic stroke, and late coronary revascularization (>90 days post-CMR). The secondary endpoint was a composite of cardiovascular death, nonfatal MI, and hospitalization for heart failure.

RESULTS

The mean age was 68±11 years (49% male). Over a median follow-up time of 8.1 (IQR 5.7, 10.4) years, 55 patients experienced MACE, and 24 met the secondary endpoint. Patients with inducible ischemia had significantly greater annualized event rates for MACE (5.7% vs. 0.7%, p<0.001) and for the secondary endpoint (2.0% vs. 0.3%, p<0.001) than those without ischemia. Multivariable analysis revealed inducible ischemia as a consistent predictor for MACE (HR 3.36, 95%CI 1.90-5.94, p<0.001) and for the secondary endpoint (HR 2.89, 95%CI 1.22-6.80, p = 0.01). Late gadolinium enhancement (LGE) was an independent predictor of the secondary endpoint (HR 3.56, 95%CI 1.25-10.13; p = 0.02). Incorporating inducible ischemia and LGE data significantly improved the model's ability to discriminate MACE risk (C-statistic increase from 0.77 to 0.83; net reclassification improvement 0.42; integrated discrimination improvement 0.05).

CONCLUSION

Stress perfusion CMR offers substantial independent prognostic value and effectively aids in reclassifying cardiovascular risk among prediabetic patients with suspected CAD.

Sudden cardiac death due to ventricular arrhythmia in diabetes mellitus: A bench to bedside review

Diabetes mellitus (DM) confers an increased risk of sudden cardiac death (SCD) independent of its associated cardiovascular comorbidities. DM induces adverse structural, electrophysiologic, and autonomic cardiac remodeling that can increase one's risk of ventricular arrhythmias and SCD. Although glycemic control and prevention of microvascular and macrovascular complications are cornerstones in the management of DM, they are not adequate for the prevention of SCD. In this narrative review, we describe the contribution of DM to the pathophysiologic mechanism of SCD beyond its role in atherosclerotic cardiovascular disease and heart failure. On the basis of this pathophysiologic framework, we outline potential preventive and therapeutic strategies to mitigate the risk of SCD in this population of high-risk patients.

Emerging opportunities to target inflammation: myocardial infarction and type 2 diabetes

After myocardial infarction (MI), patients with type 2 diabetes have an increased rate of adverse outcomes, compared to patients without. Diabetes confers a 1.5-2-fold increase in early mortality and, importantly, this discrepancy has been consistent over recent decades, despite advances in treatment and overall survival. Certain assumptions have emerged to explain this increased risk, such as differences in infarct size or coronary artery disease severity. Here, we re-evaluate that evidence and show how contemporary analyses using state-of-the-art characterization tools suggest that the received wisdom tells an incomplete story. Simultaneously, epidemiological and mechanistic biological data suggest additional factors relating to processes of diabetes-related inflammation might play a prominent role. Inflammatory processes after MI mediate injury and repair and are thus a potential therapeutic target. Recent studies have shown how diabetes affects immune cell numbers and drives changes in the bone marrow, leading to pro-inflammatory gene expression and functional suppression of healing and repair. Here, we review and re-evaluate the evidence around adverse prognosis in patients with diabetes after MI, with emphasis on how targeting processes of inflammation presents unexplored, yet valuable opportunities to improve cardiovascular outcomes in this vulnerable patient group.

Occult coronary microvascular dysfunction and ischemic heart disease in patients with diabetes and heart failure

BACKGROUND

Patients with diabetes mellitus (DM) and heart failure (HF) have worse outcomes than normoglycemic HF patients. Cardiovascular magnetic resonance (CMR) can identify ischemic heart disease (IHD) and quantify coronary microvascular dysfunction (CMD) using myocardial perfusion reserve (MPR). We aimed to quantify the extent of silent IHD and CMD in patients with DM presenting with HF.

METHODS

Prospectively recruited outpatients undergoing assessment into the etiology of HF underwent in-line quantitative perfusion CMR for calculation of stress and rest myocardial blood flow (MBF) and MPR. Exclusions included angina or history of IHD. Patients were followed up (median 3.0 years) for major adverse cardiovascular events (MACE).

RESULTS

Final analysis included 343 patients (176 normoglycemic, 84 with pre-diabetes, and 83 with DM). Prevalence of silent IHD was highest in DM 31% ( 26/83), then pre-diabetes 20% (17/84) then normoglycemia 17%, ( 30/176). Stress MBF was lowest in DM (1.53 ± 0.52), then pre-diabetes (1.59 ± 0.54) then normoglycemia (1.83 ± 0.62). MPR was lowest in DM (2.37 ± 0.85) then pre-diabetes (2.41 ± 0.88) then normoglycemia (2.61 ± 0.90). During follow-up, 45 patients experienced at least one MACE. On univariate Cox regression analysis, MPR and presence of silent IHD were both associated with MACE. However, after correction for HbA1c, age, and left ventricular ejection fraction, the associations were no longer significant.

CONCLUSION

Patients with DM and HF had higher prevalence of silent IHD, more evidence of CMD, and worse cardiovascular outcomes than their non-diabetic counterparts. These findings highlight the potential value of CMR for the assessment of silent IHD and CMD in patients with DM presenting with HF.

Comparison of intramyocellular lipid metabolism in patients with diabetes and male athletes

Despite opposing insulin sensitivity and cardiometabolic risk, both athletes and patients with type 2 diabetes have increased skeletal myocyte fat storage: the so-called "athlete's paradox". In a parallel non-randomised, non-blinded trial (NCT03065140), we characterised and compared the skeletal myocyte lipid signature of 29 male endurance athletes and 30 patients with diabetes after undergoing deconditioning or endurance training respectively. The primary outcomes were to assess intramyocellular lipid storage of the vastus lateralis in both cohorts and the secondary outcomes were to examine saturated and unsaturated intramyocellular lipid pool turnover. We show that athletes have higher intramyocellular fat saturation with very high palmitate kinetics, which is attenuated by deconditioning. In contrast, type 2 diabetes patients have higher unsaturated intramyocellular fat and blunted palmitate and linoleate kinetics but after endurance training, all were realigned with those of deconditioned athletes. Improved basal insulin sensitivity was further associated with better serum cholesterol/triglycerides, glycaemic control, physical performance, enhanced post insulin receptor pathway signalling and metabolic sensing. We conclude that insulin-resistant, maladapted intramyocellular lipid storage and turnover in patients with type 2 diabetes show reversibility after endurance training through increased contributions of the saturated intramyocellular fatty acid pools. Clinical Trial Registration: NCT03065140: Muscle Fat Compartments and Turnover as Determinant of Insulin Sensitivity (MISTY).

Non-invasive left ventricular pressure-strain loop study on cardiac fibrosis in primary aldosteronism: a comparative study with cardiac magnetic resonance imaging

We investigated the potential diagnostic value of the myocardial work indices based on speckle tracking echocardiography for cardiac fibrosis in patients with primary aldosteronism. Our observational study included 48 patients with primary aldosteronism. We performed conventional echocardiography and the left ventricular pressure-strain loop analysis. We also performed cardiac magnetic resonance imaging to evaluate cardiac replacement fibrosis defined as late gadolinium enhancement (LGE). Patients with LGE (n = 30, 62.5%) had longer duration of hypertension and higher plasma NT-proBNP than those without LGE. Besides, they had a significantly (P ≤ 0.04) higher left ventricular mass index (121.3 ± 19.5 vs. 103.3 ± 20.0 g/m2) and global wasted work (205 ± 78 vs. 141 ± 36 mmHg%) and lower global longitudinal strain (-17.7 ± 1.8 vs. -19.0 ± 2.4%) and work efficiency (GWE, 90.9 ± 2.4 vs. 93.8 ± 1.5%). Receiver Operating Characteristics analysis showed that GWE ≤ 92% had a sensitivity and specificity of 76.7% and 83.3%, respectively, for LGE with the area under curve 0.85 (P < 0.001). In conclusion, both cardiac structure and function were impaired in patients with primary aldosteronism and cardiac fibrosis. The myocardial work index GWE showed significant value for the indication of cardiac fibrosis. Characterization of cardiac fibrosis in primary aldosteronism and the detective value of clinical and echocardiographic indices. Cardiac fibrosis was presented in 30 of the 48 analyzed primary aldosteronism patients with focal high signal intensity in mid-layer myocardium in limited segments as its characterization. The global work efficiency (GWE) had a significantly higher detective value for myocardial replacement fibrosis than other measurements such as left ventricular mass index (LVMI) and NT-proBNP.

Silent myocardial infarction fatty scars detected by coronary calcium score CT scan in diabetic patients without history of coronary heart disease

OBJECTIVES

To evaluate the prevalence of intra-myocardial fatty scars (IMFS) most likely indicating previous silent myocardial infarction (SMI), as detected on coronary artery calcium (CAC) computed tomography (CT) scans in diabetic patients without history of coronary heart disease (CHD).

METHODS

Diabetic patients screened for silent coronary insufficiency in a tertiary-care, university hospital between Jan-2015 and Dec-2016 were categorized according to their CAC score in two groups comprising 242 patients with CACS = 0 and 145 patients with CACS ≥ 300. CAC-CT scans were retrospectively evaluated for subendorcardial and transmural IMFS of the left ventricle. Adipose remodeling, patients' characteristics, cardiovascular risk factors and metabolic profile were compared between groups.

RESULTS

Eighty-three (21%) patients with IMFS were identified, 55 (37.9%) in the group CACS ≥ 300 and 28 (11.6%) in the CACS = 0 (OR = 4.67; 95% CI = 2.78-7.84; p < 0.001). Total and average surface of IMFS and their number per patient were similar in both groups (p = 0.55; p = 0.29; p = 0.61, respectively). In the group CACS ≥ 300, patients with IMFS were older (p = 0.03) and had longer-lasting diabetes (p = 0.04). Patients with IMFS were older and had longer history of diabetes, reduced glomerular filtration rate, more coronary calcifications (all p < 0.05), and higher prevalence of carotid plaques (OR = 3.03; 95% CI = 1.43-6.39, p = 0.004). After correction for other variables, only a CACS ≥ 300 (OR = 5.12; 95% CI = 2.66-9.85; p < 0.001) was associated with an increased risk of having IMFS.

CONCLUSIONS

In diabetic patients without known CHD, IMFSs were found in patients without coronary calcifications, although not as frequently as in patients with heavily calcified coronary arteries. It remains to be established if this marker translates in an upwards cardiovascular risk restratification especially in diabetic patients with CACS = 0.

CLINICAL RELEVANCE STATEMENT

In diabetic patients without history of coronary heart disease, intramyocardial fatty scars, presumably of post-infarction origin, can be detected on coronary artery calcium CT scans more frequently, but not exclusively, if the coronary arteries are heavily calcified as compared to those without calcifications.

KEY POINTS

• Intramyocardial fatty scars (IMFS), presumably of post-infarction origin, can be detected on coronary artery calcium (CAC) CT scans more frequently, but not exclusively, in diabetic patients with CACS ≥ 300 as compared to patients CACS = 0. • Patients with IMFS were older and had longer history of diabetes, reduced glomerular filtration rate, and more coronary calcifications. • Carotid plaques and CACS ≥ 300 were associated with an increased risk of having IMFS, about three and five folds respectively.

Chrysin-based supramolecular cyclodextrin-calixarene drug delivery system: a novel approach for attenuating cardiac fibrosis in chronic diabetes

Introduction: Cardiac fibrosis is strongly induced by diabetic conditions. Both chrysin (CHR) and calixarene OTX008, a specific inhibitor of galectin 1 (Gal-1), seem able to reduce transforming growth factor beta (TGF-β)/SMAD pro-fibrotic pathways, but their use is limited to their low solubility. Therefore, we formulated a dual-action supramolecular system, combining CHR with sulfobutylated β-cyclodextrin (SBECD) and OTX008 (SBECD + OTX + CHR). Here we aimed to test the anti-fibrotic effects of SBECD + OTX + CHR in hyperglycemic H9c2 cardiomyocytes and in a mouse model of chronic diabetes. Methods: H9c2 cardiomyocytes were exposed to normal (NG, 5.5 mM) or high glucose (HG, 33 mM) for 48 h, then treated with SBECD + OTX + CHR (containing OTX008 0.75-1.25-2.5 µM) or the single compounds for 6 days. TGF-β/SMAD pathways, Mitogen-Activated Protein Kinases (MAPKs) and Gal-1 levels were assayed by Enzyme-Linked Immunosorbent Assays (ELISAs) or Real-Time Quantitative Reverse Transcription Polymerase chain reaction (qRT-PCR). Adult CD1 male mice received a single intraperitoneal (i.p.) administration of streptozotocin (STZ) at a dosage of 102 mg/kg body weight. From the second week of diabetes, mice received 2 times/week the following i.p. treatments: OTX (5 mg/kg)-SBECD; OTX (5 mg/kg)-SBECD-CHR, SBECD-CHR, SBECD. After a 22-week period of diabetes, mice were euthanized and cardiac tissue used for tissue staining, ELISA, qRT-PCR aimed to analyse TGF-β/SMAD, extracellular matrix (ECM) components and Gal-1. Results: In H9c2 cells exposed to HG, SBECD + OTX + CHR significantly ameliorated the damaged morphology and reduced TGF-β1, its receptors (TGFβR1 and TGFβR2), SMAD2/4, MAPKs and Gal-1. Accordingly, these markers were reduced also in cardiac tissue from chronic diabetes, in which an amelioration of cardiac remodeling and ECM was evident. In both settings, SBECD + OTX + CHR was the most effective treatment compared to the other ones. Conclusion: The CHR-based supramolecular SBECD-calixarene drug delivery system, by enhancing the solubility and the bioavailability of both CHR and calixarene OTX008, and by combining their effects, showed a strong anti-fibrotic activity in rat cardiomyocytes and in cardiac tissue from mice with chronic diabetes. Also an improved cardiac tissue remodeling was evident. Therefore, new drug delivery system, which could be considered as a novel putative therapeutic strategy for the treatment of diabetes-induced cardiac fibrosis.

The value of cardiac magnetic resonance post-contrast T1 mapping in improving the evaluation of myocardial infarction

Objective

To explore the additional value of cardiac magnetic resonance (CMR) post-contrast T1 mapping in the detection of myocardial infarction, compared with late gadolinium enhancement (LGE).

Materials and methods

A CMR database of consecutive patients with myocardial infarction was retrospectively analyzed. All patients were scanned at 3 T magnetic resonance; they underwent conventional CMR (including LGE) and post-contrast T1 mapping imaging. Two radiologists interpreted the CMR images using a 16-segment model. The first interpretation included only LGE images. After 30 days, the same radiologists performed a second analysis of random LGE images, with the addition of post-contrast T1 mapping images. Images were analyzed to diagnose myocardial scars, and the transmural extent of each scar was visually evaluated. Diagnoses retained after LGE were compared with diagnoses retained after the addition of post-contrast T1 mapping.

Results

In total, 80 patients (1,280 myocardial segments) were included in the final analysis. After the addition of post-contrast T1 mapping, eight previously unidentified subendocardial scars were detected. Compared with LGE images, the percentage of infarcted segments was higher after the addition of post-contrast T1 mapping images (21.7% vs. 22.3%, P = 0.008), the percentage of uncertain segments was lower after the addition of post-contrast T1 mapping (0.8% vs. 0.1%, P = 0.004), and the percentage of uncertain transmural extent of scarring was lower after the addition of post-contrast T1 mapping (0.9% vs. 0.1%, P = 0.001).

Conclusion

The addition of post-contrast T1 mapping after LGE helps to improve the detection of myocardial infarction, as well as the assessment of the transmural extent of scarring.

NPRC deletion attenuates cardiac fibrosis in diabetic mice by activating PKA/PKG and inhibiting TGF-β1/Smad pathways

Cardiac fibrosis plays a key role in the progression of diabetic cardiomyopathy (DCM). Previous studies demonstrated the cardioprotective effects of natriuretic peptides. However, the effects of natriuretic peptide receptor C (NPRC) on cardiac fibrosis in DCM remains unknown. Here, we observed that myocardial NPRC expression was increased in mice and patients with DCM. NPRC-/- diabetic mice showed alleviated cardiac fibrosis, as well as improved cardiac function and remodeling. NPRC knockdown in both cardiac fibroblasts and cardiomyocytes decreased collagen synthesis and proliferation of cardiac fibroblasts. RNA sequencing identified that NPRC deletion up-regulated the expression of TGF-β-induced factor homeobox 1 (TGIF1), which inhibited the phosphorylation of Smad2/3. Furthermore, TGIF1 up-regulation was mediated by the activation of cAMP/PKA and cGMP/PKG signaling induced by NPRC deletion. These findings suggest that NPRC deletion attenuated cardiac fibrosis and improved cardiac remodeling and function in diabetic mice, providing a promising approach to the treatment of diabetic cardiac fibrosis.

Relationship of OCT-defined plaque characteristics with CCTA-derived coronary inflammation and CMR-derived global coronary flow reserve in patients with acute coronary syndrome

BACKGROUND

The relationship of layered plaque detected by optical coherence tomography (OCT) with coronary inflammation and coronary flow reserve (CFR) remains elusive. We aimed to investigate the association of OCT-defined layered plaque with pericoronary adipose tissue (PCAT) inflammation assessed by coronary computed tomography angiography (CCTA) and global (G)-CFR assessed by cardiac magnetic resonance imaging (CMR) in patients with acute coronary syndrome (ACS).

METHODS

We retrospectively investigated 88 patients with first ACS who underwent preprocedural CCTA, OCT imaging of the culprit lesion prior to primary/urgent percutaneous coronary intervention (PCI), and postprocedural CMR. All patients were divided into two groups according to the presence and absence of OCT-defined layered plaque at the culprit lesion. Coronary inflammation was assessed by the mean value of PCAT attenuation (-190 to -30 HU) of the three major coronary vessels. G-CFR was obtained by quantifying absolute coronary sinus flow at rest and during maximum hyperemia. CCTA and CMR findings were compared between the groups.

RESULTS

In a total of 88 patients, layered plaque was detected in 51 patients (58.0%). The patients with layered plaque had higher three-vessel-PCAT attenuation value (-68.58 ± 6.41 vs. -71.60 ± 5.21 HU, P = 0.021) and culprit vessel-PCAT attenuation value (-67.69 ± 7.76 vs. -72.07 ± 6.57 HU, P = 0.007) than those with non-layered plaque. The patients with layered plaque had lower G-CFR value (median, 2.26 [interquartile range, 1.78, 2.89] vs. 3.06 [2.41, 3.90], P = 0.003) than those with non-layered plaque.

CONCLUSIONS

The presence of OCT-defined layered plaque at the culprit lesion was associated with high PCAT attenuation and low G-CFR after primary/urgent PCI in patients with ACS. OCT assessment of culprit plaque morphology and detection of layered plaque may help identify increased pericoronary inflammation and impaired CFR, potentially providing the risk stratification in patients with ACS and residual microvascular dysfunction after PCI.

Cardiovascular Magnetic Resonance Imaging as an Adjunct to the Evaluation of Cardiovascular Involvement in Diabetes Mellitus

Diabetes mellitus (DM) is a new epidemic which has presented an immense increase in recent decades, due to the rapid increase in obesity. Cardiovascular disease (CVD) significantly reduces life expectancy and is the main cause of death in type 2 diabetes mellitus (T2DM). Strict glycemic control is a well-established method to combat microvascular CVD of type 1 diabetes mellitus (T1DM); its role against CVD of the T2DM risk has not been well documented. Therefore, the most efficient prevention is multifactorial risk factor reduction. Recently, the European Society of Cardiology published its 2019 recommendations on CVD in DM. Although all clinical points were discussed in this document, only a few comments were presented about when and how we should recommend cardiovascular (CV) imaging. Currently, CV imaging is the "must" in CV noninvasive evaluation. Alterations in CV imaging parameters can lead to early recognition of various types of CVD. In this paper, we briefly discuss the role of noninvasive imaging modalities, emphasizing the benefits of including cardiovascular magnetic resonance (CMR) in the evaluation of DM. CMR, in the same examination, can provide an assessment of tissue characterization, perfusion and function, with excellent reproducibility and without radiation or limitations, due to the body habitus. Therefore, it can play a dominant role in the prevention and risk stratification of DM. The suggested protocol for DM evaluation should include routine annual echocardiographic evaluation of all DM patients and CMR assessment of those with poorly controlled DM, microalbuminuria, heart failure, arrhythmia and recent alterations in clinical or echocardiographic evaluation.

Myocardial Perfusion Imaging by Cardiovascular Magnetic Resonance: Research Progress and Current Implementation

Cardiovascular diseases pose a significant health and economic burden worldwide, with coronary artery disease still recognized as a major problem. It is closely associated with hypertension, diabetes, obesity, smoking, lack of exercise, poor diet, and excessive alcohol consumption, which may lead to macro- and microvascular abnormalities in the heart. Coronary artery stenosis reduces the local supply of oxygen and nutrients to the myocardium and results in reduced levels of myocardial perfusion, which can lead to more severe conditions and irreversible damage to myocardial tissues. Therefore, accurate evaluation of myocardial perfusion abnormalities in patients with these risk factors is critical. As technology advances, magnetic resonance myocardial perfusion imaging has become more accurate at evaluating the myocardial microcirculation and has shown a powerful ability to detect myocardial ischemia. The purpose of this review is to summarize the principle, research progress of acquisition and analysis, and clinical implementation of cardiovascular magnetic resonance (CMR) myocardial perfusion imaging.

Systemic proinflammatory-profibrotic response in aortic stenosis patients with diabetes and its relationship with myocardial remodeling and clinical outcome

BACKGROUND

Previous studies have mainly focused more on how diabetes affects the valve than the myocardium in aortic stenosis (AS). In the pressure-overloaded heart, myocardial fibrosis is an important driver of the progression from compensated hypertrophy to heart failure. Using comprehensive noninvasive imaging and plasma proteomics, we investigated whether and how diabetes aggravates the remodeling of the myocardium and its relation with prognosis in AS patients.

METHODS

Severe AS patients were enrolled in two prospective cohorts for imaging and biomarker analysis. The imaging cohort (n = 253) underwent echocardiography and cardiac magnetic resonance, and the biomarker cohort (n = 100) blood sampling with multiplex proximity extension assay for 92 proteomic biomarkers. The composite outcome of hospitalization for heart failure admissions and death was assessed in the imaging cohort.

RESULTS

Diabetic patients were older (70.4 ± 6.8 versus 66.7 ± 10.1 years) with more advanced ventricular diastolic dysfunction and increased replacement and diffuse interstitial fibrosis (late gadolinium enhancement % 0.3 [0.0-1.6] versus 0.0 [0.0-0.5], p = 0.009; extracellular volume fraction % 27.9 [25.7-30.1] versus 26.7 [24.9-28.5], p = 0.025) in the imaging cohort. Plasma proteomics analysis of the biomarker cohort revealed that 9 proteins (E-selectin, interleukin-1 receptor type 1, interleukin-1 receptor type 2, galectin-4, intercellular adhesion molecule 2, integrin beta-2, galectin-3, growth differentiation factor 15, and cathepsin D) were significantly elevated and that pathways related to inflammatory response and extracellular matrix components were enriched in diabetic AS patients. During follow-up (median 6.3 years), there were 53 unexpected heart failure admissions or death in the imaging cohort. Diabetes was a significant predictor of heart failure and death, independent of clinical covariates and aortic valve replacement (HR 1.88, 95% CI 1.06-3.31, p = 0.030).

CONCLUSIONS

Plasma proteomic analyses indicate that diabetes potentiates the systemic proinflammatory-profibrotic milieu in AS patients. These systemic biological changes underlie the increase of myocardial fibrosis, diastolic dysfunction, and worse clinical outcomes in severe AS patients with concomitant diabetes.

Myocardial Involvement After Hospitalization for COVID-19 Complicated by Troponin Elevation: A Prospective, Multicenter, Observational Study

BACKGROUND

Acute myocardial injury in hospitalized patients with coronavirus disease 2019 (COVID-19) has a poor prognosis. Its associations and pathogenesis are unclear. Our aim was to assess the presence, nature, and extent of myocardial damage in hospitalized patients with troponin elevation.

METHODS

Across 25 hospitals in the United Kingdom, 342 patients with COVID-19 and an elevated troponin level (COVID+/troponin+) were enrolled between June 2020 and March 2021 and had a magnetic resonance imaging scan within 28 days of discharge. Two prospective control groups were recruited, comprising 64 patients with COVID-19 and normal troponin levels (COVID+/troponin-) and 113 patients without COVID-19 or elevated troponin level matched by age and cardiovascular comorbidities (COVID-/comorbidity+). Regression modeling was performed to identify predictors of major adverse cardiovascular events at 12 months.

RESULTS

Of the 519 included patients, 356 (69%) were men, with a median (interquartile range) age of 61.0 years (53.8, 68.8). The frequency of any heart abnormality, defined as left or right ventricular impairment, scar, or pericardial disease, was 2-fold greater in cases (61% [207/342]) compared with controls (36% [COVID+/troponin-] versus 31% [COVID-/comorbidity+]; P<0.001 for both). More cases than controls had ventricular impairment (17.2% versus 3.1% and 7.1%) or scar (42% versus 7% and 23%; P<0.001 for both). The myocardial injury pattern was different, with cases more likely than controls to have infarction (13% versus 2% and 7%; P<0.01) or microinfarction (9% versus 0% and 1%; P<0.001), but there was no difference in nonischemic scar (13% versus 5% and 14%; P=0.10). Using the Lake Louise magnetic resonance imaging criteria, the prevalence of probable recent myocarditis was 6.7% (23/342) in cases compared with 1.7% (2/113) in controls without COVID-19 (P=0.045). During follow-up, 4 patients died and 34 experienced a subsequent major adverse cardiovascular event (10.2%), which was similar to controls (6.1%; P=0.70). Myocardial scar, but not previous COVID-19 infection or troponin, was an independent predictor of major adverse cardiovascular events (odds ratio, 2.25 [95% CI, 1.12-4.57]; P=0.02).

CONCLUSIONS

Compared with contemporary controls, patients with COVID-19 and elevated cardiac troponin level have more ventricular impairment and myocardial scar in early convalescence. However, the proportion with myocarditis was low and scar pathogenesis was diverse, including a newly described pattern of microinfarction.

REGISTRATION

URL: https://www.isrctn.com; Unique identifier: 58667920.

Qualitative and Quantitative Stress Perfusion Cardiac Magnetic Resonance in Clinical Practice: A Comprehensive Review

Stress cardiovascular magnetic resonance (CMR) imaging is a well-validated non-invasive stress test to diagnose significant coronary artery disease (CAD), with higher diagnostic accuracy than other common functional imaging modalities. One-stop assessment of myocardial ischemia, cardiac function, and myocardial viability qualitatively and quantitatively has been proven to be a cost-effective method in clinical practice for CAD evaluation. Beyond diagnosis, stress CMR also provides prognostic information and guides coronary revascularisation. In addition to CAD, there is a large body of literature demonstrating CMR's diagnostic performance and prognostic value in other common cardiovascular diseases (CVDs), especially coronary microvascular dysfunction (CMD). This review focuses on the clinical applications of stress CMR, including stress CMR scanning methods, practical interpretation of stress CMR images, and clinical utility of stress CMR in a setting of CVDs with possible myocardial ischemia.

Cardiovascular magnetic resonance phenotyping of heart failure with mildly reduced ejection fraction

AIMS

The 2016 European Society of Cardiology Heart Failure Guidelines defined a new category: heart failure with mid-range ejection fraction (HFmrEF) of 40-49%. This new category was highlighted as having limited evidence and research was advocated into underlying characteristics, pathophysiology, and diagnosis. We used multi-parametric cardiovascular magnetic resonance (CMR) to define the cardiac phenotype of presumed non-ischaemic HFmrEF.

METHODS AND RESULTS

Patients (N = 300, 62.7 ± 13 years, 63% males) with a clinical diagnosis of heart failure with no angina symptoms, history of myocardial infarction, or coronary intervention were prospectively recruited. Patients underwent clinical assessment and CMR including T1 mapping, extracellular volume (ECV) mapping, late gadolinium enhancement, and measurement of myocardial blood flow at rest and maximal hyperaemia. Of 273 patients in the final analysis, 93 (34%) patients were categorized as HFmrEF, 46 (17%) as heart failure with preserved ejection fraction (HFpEF), and 134 (49%) as heart failure with reduced ejection fraction (HFrEF). Nineteen (20%) patients with HFmrEF had evidence of occult ischaemic heart disease. Diffuse fibrosis and hyperaemic myocardial blood flow were similar in HFmrEF and HFpEF, but HFmrEF showed significantly lower native T1 (1311 ± 32 vs. 1340 ± 45 ms, P < 0.001), ECV (24.6 ± 3.2 vs. 26.3 ± 3.1%, P < 0.001), and higher myocardial perfusion reserve (2.75 ± 0.84 vs. 2.28 ± 0.84, P < 0.001) compared with HFrEF.

CONCLUSION

Patients with HFmrEF share most phenotypic characteristics with HFpEF, including the degree of microvascular impairment and fibrosis, but have a high prevalence of occult ischaemic heart disease similar to HFrEF. Further work is needed to confirm how the phenotype of HFmrEF responds to medical therapy.

Multi-modality cardiac imaging in the management of diabetic heart disease

Diabetic heart disease is a major healthcare problem. Patients with diabetes show an excess of death from cardiovascular causes, twice as high as the general population and those with diabetes type 1 and longer duration of the disease present with more severe cardiovascular complications. Premature coronary artery disease and heart failure are leading causes of morbidity and reduced life expectancy. Multimodality cardiac imaging, including echocardiography, cardiac computed tomography, nuclear medicine, and cardiac magnetic resonance play crucial role in the diagnosis and management of different pathologies included in the definition of diabetic heart disease. In this review we summarise the utility of multi-modality cardiac imaging in characterising ischaemic and non-ischaemic causes of diabetic heart disease and give an overview of the current clinical practice. We also describe emerging imaging techniques enabling early detection of coronary artery inflammation and the non-invasive characterisation of the atherosclerotic plaque disease. Furthermore, we discuss the role of MRI-derived techniques in studying altered myocardial metabolism linking diabetes with the development of diabetic cardiomyopathy. Finally, we discuss recent data regarding the use of artificial intelligence applied to large imaging databases and how those efforts can be utilised in the future in screening of patients with diabetes for early signs of disease.

Additional prognostic value of stress cardiovascular magnetic resonance for cardiovascular risk stratification after a cryptogenic ischemic stroke

Background

One-third of ischemic strokes are “cryptogenic” without clearly identified etiology. Although coronary artery disease (CAD) is the main cause of death after stroke, the interest in CAD screening in patients with cryptogenic stroke is still debated.

Aim

The aim of the study was to assess the incremental prognostic value of stress cardiovascular magnetic resonance (CMR) beyond traditional risk factors for predicting cardiovascular events in patients with a prior cryptogenic ischemic stroke.

Materials and methods

Between 2008 and 2021, consecutive patients with prior cryptogenic strokes referred for stress CMR were included and followed for the occurrence of major adverse cardiovascular events (MACEs), defined by cardiovascular death or non-fatal myocardial infarction (MI). Univariable and multivariable Cox regressions were performed to determine the prognostic value of unrecognized MI and silent ischemia.

Results

Of 542 patients (55.2% male, mean age 71.4 ± 8.8 years) who completed the follow-up (median 5.9 years), 66 (12.2%) experienced MACE. Silent ischemia and unrecognized MI were detected in 18 and 17% of patients, respectively. Using Kaplan–Meier analysis, silent ischemia and unrecognized MI were associated with the occurrence of MACE [hazard ratio, HR: 8.43 (95% CI: 5.11–13.9); HR: 7.87 (95% CI: 4.80–12.9), respectively, p < 0.001]. In multivariable analysis, silent ischemia and unrecognized MI were independent predictors of MACE [HR: 8.08 (95% CI: 4.21–15.5); HR: 6.65 (95% CI: 3.49–12.7), respectively, p < 0.001]. After adjustment, stress CMR findings showed the best improvement in model discrimination and reclassification above traditional risk factors (C-statistic improvement: 0.13; NRI = 0.428; IDI = 0.048).

Conclusion

In patients with prior cryptogenic stroke, stress CMR findings have an incremental prognostic value to predict MACE over traditional risk factors.

NLRP3 Inflammasome/Pyroptosis: A Key Driving Force in Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM), a serious diabetic complication, is a kind of low-grade inflammatory cardiovascular disorder. Due to the high risk of morbidity and mortality, DCM has demanded the attention of medical researchers worldwide. The pathophysiological nature of DCM is intricate, and the genesis and development of which are a consequence of the coaction of many factors. However, the exact pathogenesis mechanism of DCM remains unclear. Pyroptosis is a newly identified programmed cell death (PCD) that is directly related to gasdermin D(GSDMD). It is characterized by pore formation on the cell plasma membrane, the release of inflammatory mediators, and cell lysis. The initiation of pyroptosis is closely correlated with NOD-like receptor 3 (NLRP3) activation, which activates caspase-1 and promotes the cleaving of GSDMD. In addition to adjusting the host’s immune defense, NLRP3 inflammasome/pyroptosis plays a critical role in controlling the systemic inflammatory response. Recent evidence has indicated that NLRP3 inflammasome/pyroptosis has a strong link with DCM. Targeting the activation of NLRP3 inflammasome or pyroptosis may be a hopeful therapeutic strategy for DCM. The focus of this review is to summarize the relevant mechanisms of pyroptosis and the relative contributions in DCM, highlighting the potential therapeutic targets in this field.

The role of cardiac magnetic resonance imaging in the assessment of heart failure with preserved ejection fraction

Heart failure (HF) is a major cause of morbidity and mortality worldwide. Current classifications of HF categorize patients with a left ventricular ejection fraction of 50% or greater as HF with preserved ejection fraction or HFpEF. Echocardiography is the first line imaging modality in assessing diastolic function given its practicality, low cost and the utilization of Doppler imaging. However, the last decade has seen cardiac magnetic resonance (CMR) emerge as a valuable test for the sometimes challenging diagnosis of HFpEF. The unique ability of CMR for myocardial tissue characterization coupled with high resolution imaging provides additional information to echocardiography that may help in phenotyping HFpEF and provide prognostication for patients with HF. The precision and accuracy of CMR underlies its use in clinical trials for the assessment of novel and repurposed drugs in HFpEF. Importantly, CMR has powerful diagnostic utility in differentiating acquired and inherited heart muscle diseases presenting as HFpEF such as Fabry disease and amyloidosis with specific treatment options to reverse or halt disease progression. This state of the art review will outline established CMR techniques such as transmitral velocities and strain imaging of the left ventricle and left atrium in assessing diastolic function and their clinical application to HFpEF. Furthermore, it will include a discussion on novel methods and future developments such as stress CMR and MR spectroscopy to assess myocardial energetics, which show promise in unraveling the mechanisms behind HFpEF that may provide targets for much needed therapeutic interventions.

The role of cardiac magnetic resonance imaging in defining the prognosis of patients with acute <i>ST</i>-segment elevation myocardial infarction. Part 2. Assessment of the disease prognosis

Currently the incidence of congestive heart failure after ST-segment elevation myocardial infarction (STEMI) tends to increase. Reperfusion therapy is still the only effective method to reduce an infarct size. Therefore, there is a high unmet need of novel cardioprotective treatments that would improve outcomes in such patients. Recent advances in cardiovascular magnetic resonance (CMR) methods enabled the identification of certain new infarct characteristics associated with the development of heart failure and sudden cardiac death. These characteristics can help identify new groups of high risk patients and used as a targets for novel cardioprotective treatments. This part of the review summarizes novel CMR-based characteristics of myocardial infarction and their role in the prognostic stratification of STEMI patients.

Glycemic Control and the Heart: The Tale of Diabetic Cardiomyopathy Continues

Cardiovascular diseases are the leading cause of death in people with diabetes. Diabetic cardiomyopathy (DC) is an important complication of diabetes and represents a distinct subtype of heart failure that occurs in absence of cardiovascular diseases. Chronic hyperglycemia and hyperinsulinemia along with insulin resistance and inflammatory milieu are the main mechanisms involved in the pathophysiology of DC. Changes in lifestyle favoring healthy dietary patterns and physical activity, combined with more innovative anti-diabetes therapies, are the current treatment strategies to safeguard the cardiovascular system. This review aims at providing an updated comprehensive overview of clinical, pathogenetic, and molecular aspects of DC, with a focus on the effects of anti-hyperglycemic drugs on the prevention of pump dysfunction and consequently on cardiovascular health in type 2 diabetes.

Multimodality imaging approach to left ventricular dysfunction in diabetes: an expert consensus document from the European Association of Cardiovascular Imaging

Heart failure (HF) is among the most important and frequent complications of diabetes mellitus (DM). The detection of subclinical dysfunction is a marker of HF risk and presents a potential target for reducing incident HF in DM. Left ventricular (LV) dysfunction secondary to DM is heterogeneous, with phenotypes including predominantly systolic, predominantly diastolic, and mixed dysfunction. Indeed, the pathogenesis of HF in this setting is heterogeneous. Effective management of this problem will require detailed phenotyping of the contributions of fibrosis, microcirculatory disturbance, abnormal metabolism, and sympathetic innervation, among other mechanisms. For this reason, an imaging strategy for the detection of HF risk needs to not only detect subclinical LV dysfunction (LVD) but also characterize its pathogenesis. At present, it is possible to identify individuals with DM at increased risk HF, and there is evidence that cardioprotection may be of benefit. However, there is insufficient justification for HF screening, because we need stronger evidence of the links between the detection of LVD, treatment, and improved outcome. This review discusses the options for screening for LVD, the potential means of identifying the underlying mechanisms, and the pathways to treatment.

Association of myocardial fibrosis detected by late gadolinium-enhanced MRI with clinical outcomes in patients with diabetes: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis assessed the associations of myocardial fibrosis detected by late gadolinium-enhanced (LGE)-MRI with the risk of major adverse cardiac and cerebrovascular events (MACCEs) and major adverse cardiac events (MACEs) in patients with diabetes.

DESIGN

Systematic review and meta-analysis reported in accordance with the guidelines of the Meta-analysis of Observational Studies in Epidemiology statement.

DATA SOURCES

We searched the Medline, Embase and Cochrane by Ovid databases for studies published up to 27 August 2021.

ELIGIBILITY CRITERIA

Prospective or respective cohort studies were included if they reported the HR and 95% CIs for MACCEs/MACEs in patients with either type 1 or 2 diabetes and LGE-MRI-detected myocardial fibrosis compared with patients without LGE-MRI-detected myocardial fibrosis and if the articles were published in the English language.

DATA EXTRACTION AND SYNTHESIS

Two review authors independently extracted data and assessed the quality of the included studies. Pooled HRs and 95% CIs were analysed using a random effects model. Heterogeneity was assessed using forest plots and I2 statistics.

RESULTS

Eight studies with 1121 patients with type 1 or type 2 diabetes were included in this meta-analysis, and the follow-up ranged from 17 to 70 months. The presence of myocardial fibrosis detected by LGE-MRI was associated with an increased risk for MACCEs (HR: 2.58; 95% CI 1.42 to 4.71; p=0.002) and MACEs (HR: 5.28; 95% CI 3.20 to 8.70; p<0.001) in patients with diabetes. Subgroup analysis revealed that ischaemic fibrosis detected by LGE was associated with MACCEs (HR 3.80, 95% CI 2.38 to 6.07; p<0.001) in patients with diabetes.

CONCLUSIONS

This study demonstrated that ischaemic myocardial fibrosis detected by LGE-MRI was associated with an increased risk of MACCEs/MACEs in patients with diabetes and may be an imaging biomarker for risk stratification. Whether LGE-MRI provides incremental prognostic information with respect to MACCEs/MACEs over risk stratification by conventional cardiovascular risk factors requires further study.

Myocardial Extracellular Volume Fraction and T1 Mapping by Cardiac Magnetic Resonance Compared Between Patients With and Without Type 2 Diabetes, and the Effect of ECV and T2D on Cardiovascular Outcomes

Background: To investigate the difference in myocardial extracellular volume fraction (ECV) by cardiac magnetic resonance (CMR) T1 mapping between patients with and without type 2 diabetes (T2D), and the effect of ECV and T2D on cardiovascular (CV) outcomes. Methods: All patients aged > 18 years with known or suspected coronary artery disease who underwent CMR for assessment of myocardial ischemia or myocardial viability at the Department of Cardiology of the Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand from September 2017 to December 2018 were screened for inclusion eligibility. Left ventricular ejection fraction (LVEF), late gadolinium enhancement, and T1 mapping were performed. ECV values were derived from myocardial native T1 and contrast-enhanced T1 values that were obtained using modified Look-Locker inversion recovery at the septum of the mid-cavity short-axis map. Demographic data, clinical characteristics, and CV outcomes were collected by retrospective chart review. Composite CV outcomes included CV death, acute coronary syndrome, heart failure hospitalization, or ventricular tachycardia (VT)/ventricular fibrillation. Results: A total of 739 subjects (mean age: 69.5 ± 14.0 years, 49.3% men) were included. Of those, 188 subjects had T2D (25.4%). ECV was significantly higher in T2D than in non-T2D (30.0 ± 5.9% vs. 28.8 ± 4.7%, p = 0.004). During the mean follow-up duration of 26.2 ± 8.5 months, 43 patients (5.8%) had a clinical composite outcome, as follows: three CV death (0.4%), seven acute coronary syndrome (0.9%), 33 heart failure hospitalization (4.5%), and one VT (0.1%). T2D, low LVEF, and high ECV were all identified as independent predictors of CV events. Patients with T2D and high ECV had the highest risk of CV events. Conclusion: Among patients with known or suspected coronary artery disease, patients with T2D had a higher ECV. T2D and high ECV were both found to be independent risk factors for adverse CV outcomes.

Myocardial fibrosis assessed by magnetic resonance imaging in asymptomatic heterozygous familial hypercholesterolemia: the cholcoeur study

BACKGROUND

Familial Hypercholesterolemia (FH) is an underdiagnosed condition with an increased cardiovascular risk. It is unknown whether lipid accumulation plays a role in structural myocardial changes. Cardiovascular Magnetic Resonance (CMR) is the reference technique for the morpho-functional evaluation of heart chambers through cine sequences and for myocardial tissue characterization through late gadolinium enhancement (LGE) and T1 mapping images. We aimed to assess the prevalence of myocardial fibrosis in FH patients.

METHODS

Seventy-two asymptomatic subjects with genetically confirmed FH (mean age 49·24, range 40 to 60 years) were prospectively recruited along with 31 controls without dyslipidaemia matched for age, sex, BMI, and other cardiovascular risk factors. All underwent CMR including cine, LGE, pre- and post-contrast T1 mapping. Extracellular volume (ECV) and enhancement rate of the myocardium (ERM = difference between pre- and post-contrast myocardial T1, normalized by pre-contrast myocardial T1) were calculated.

FINDINGS

Five FH patients and none of the controls had intramyocardial LGE (p= 0·188). While no changes in Native T1 and ECV were found, post-contrast T1 was significantly lower (430·6 ± 55ms vs. 476·1 ± 43ms, p<0·001) and ERM was higher (57·44± 5·99 % vs 53·04±4·88, p=0·005) in HeFH patients compared to controls. Moreover, low post-contrast T1 was independently associated with the presence of xanthoma (HR 5·221 [1·04-26·28], p= 0·045). A composite score combining the presence of LGE, high native T1 and high ERM (defined as ≥ mean ± 1·5 SD) was found in 20·8% of the HeFH patients vs. 0% in controls (p<0·000, after adjustment for main confounders).

INTERPRETATION

CMR revealed early changes in myocardial tissue characteristics in HeFH patients, that should foster further work to better understand and prevent the underlying pathophysiological processes.

Magnetic Resonance Texture Analysis in Myocardial Infarction

Texture analysis (TA) is a newly arisen field that can detect the invisible MRI signal changes among image pixels. Myocardial infarction (MI) is cardiomyocyte necrosis caused by myocardial ischemia and hypoxia, becoming the primary cause of death and disability worldwide. In recent years, various TA studies have been performed in patients with MI and show a good clinical application prospect. This review briefly presents the main pathogenesis and pathophysiology of MI, introduces the overview and workflow of TA, and summarizes multiple magnetic resonance TA (MRTA) clinical applications in MI. We also discuss the facing challenges currently for clinical utilization and propose the prospect.

High prevalence of fragmented QRS on electrocardiography in Japanese patients with diabetes irrespective of metabolic syndrome

AIMS/INTRODUCTION

Fragmented QRS (fQRS) on electrocardiography is a marker of myocardial fibrosis and myocardial scar formation. This study aimed to clarify the relationship of fQRS with diabetes mellitus and metabolic syndrome (MetS) in Japanese patients.

MATERIALS AND METHODS

Approximately 702 individuals who had a routine health checkup at the Hokuriku Health Service Association (Toyama, Japan) in October 2014 were enrolled and categorized into one of the following four groups based on MetS and diabetes mellitus status: with diabetes mellitus (+) MetS+ (164 participants); diabetes mellitus+ without MetS (Mets-; 103 participants); diabetes mellitus- MetS+ (133 participants); and diabetes mellitus- MetS- (302 participants). fQRS was assessed using the results of electrocardiography.

RESULTS

The prevalence of fQRS was statistically higher in patients with diabetes mellitus+ MetS+ (37%) and diabetes mellitus+ MetS- (35%), than those with diabetes mellitus- MetS+ (14%) or diabetes mellitus- MetS- (10%; P < 0.0001). Significant differences were observed between the fQRS(+) and fQRS(-) groups for age, sex, waist circumference, heart rate, hypertension, hemoglobin A1c, total cholesterol, MetS and diabetes mellitus. The area under the receiver operating characteristic curve for traditional risk factors and diabetes mellitus was 0.72 (P = 0.0007, 95% confidence interval 0.67-0.76), and for traditional risk factors and MetS it was 0.67 (P = 0.28, 95% confidence interval 0.62-0.72). Patients with diabetes mellitus had more than threefold higher likelihood of showing fQRS (odds ratio 3.41; 95% confidence interval 2.25-5.22; P < 0.0001) compared with the reference group without diabetes mellitus, after adjusting for age, sex, dyslipidemia, hypertension and waist circumference.

CONCLUSIONS

fQRS was observed more frequently in diabetes mellitus patients than in MetS and control individuals. Diabetes mellitus was the most significant determinant for fQRS among MetS and other traditional metabolic risk factors.

Prognostic value of subclinical myocardial necrosis using high-sensitivity cardiac troponin T in patients with prediabetes

BACKGROUND

Risk stratification of patients with prediabetes is an unmet clinical need. Here, we examine the utility of subclinical myocardial necrosis assessed by high-sensitivity cardiac troponin T (hs-cTnT) in predicting health outcomes in stable subjects with prediabetes.

METHODS

hs-cTnT was analyzed by a high-sensitivity assay (Roche 5th generation) in 2631 stable subjects with prediabetes (HbA1c 5.7-6.4% or fasting glucose 100-125 mg/dL without previous diagnosis of diabetes or glucose-lowering therapy) who underwent elective coronary angiography for cardiac evaluation, and followed for major adverse cardiac events (MACE; death, myocardial infarction, stroke) over 3 years and all-cause mortality over 5 years.

RESULTS

In our study cohort, hs-cTnT was highly prevalent with a median level of 13 ng/L (interquartile range 8.2-21.6 ng/L). Hs-cTnT was independently associated with incident MACE at 3 years (Q4 vs. Q1 adjusted hazard ratio (HR) 2.42 [95% CI 1.69-3.46], P < 0.001) and 5-year mortality (adjusted HR 3.8 [95% CI 2.55-5.67], P < 0.001). This association remained significant in all subsets after adjustment for traditional risk factors and multiple factors known to increase hs-cTnT levels. Moreover, hs-cTnT independently predicted event risk in primary prevention subjects (n = 557, HR 5.46 [95% CI 1.50-19.89), p < 0.01) for MACE; HR 9.53 [95% CI 2.08-43.73] for all-cause mortality) and secondary prevention subjects (n = 2074, HR 1.86 [95% CI 1.31-2.66], P < 0.001 for MACE; and 2.7 [95% CI 1.79-4.08), P < 0.001 for all-cause mortality).

CONCLUSIONS

In stable prediabetic subjects, the presence of subclinical myocardial necrosis as detected by hs-cTnT portends heightened long-term adverse cardiovascular event risk. Hs-cTnT levels may help to stratify risk and improve clinical decision making in patients with prediabetes. Trial registration ClinicalTrials.gov Identifier: NCT00590200.

Relationship between frontal QRS-T duration and the severity of coronary artery disease in who were non-diabetic and had stable angina pectoris

OBJECTIVE

There is a known relationship between frontal-QRS-T (F-QRS-T) angle and coronary artery disease (CAD). This study examined the relationship between F-QRS-T angle changes and CAD severity in patients with stable CAD.

METHODS

A total of 202 patients were included in the study after the implementation of exclusion criteria among 894 patients, who were admitted to the outpatient clinic with stable angina pectoris between September 2018 and September 2019. The F-QRS-T angle calculated on the 12-lead electrocardiograms (ECGs) of the patients (taken in the outpatient clinic), and the CAD severity calculated using the Gensini score in patients undergoing coronary angiography were compared.

RESULTS

Of the patients included in the study, 38.6% were female and 61.4% were male. The mean age was calculated as 60.16±11.27 years, and 52% of the patients had hypertension. There was no difference between the groups in terms of demographic and clinical values. In a comparison of CAD severity and F-QRS-T angles, the F-QRS-T angle was seen to be statistically significantly higher in the severe CAD group [91°° (102/79)] compared to the group with mild CAD [53°° (64/38)]. In the multivariate logistic regression analysis, there was a significant association between the F-QRS-T angle (odds ratio=1.09, 95% confidence interval=1.06-1.11, p<0.001) and CAD severity.

CONCLUSION

It seems that CAD severity in patients who were non-diabetic and had stable angina pectoris is associated with the F-QRS-T angle.

Diabetic patients with chronic kidney disease: Non-invasive assessment of cardiovascular risk

The prevalence and burden of diabetes mellitus and chronic kidney disease on global health and socioeconomic development is already heavy and still rising. Diabetes mellitus by itself is linked to adverse cardiovascular events, and the presence of concomitant chronic kidney disease further amplifies cardiovascular risk. The culmination of traditional (male gender, smoking, advanced age, obesity, arterial hypertension and dyslipidemia) and non-traditional risk factors (anemia, inflammation, proteinuria, volume overload, mineral metabolism abnormalities, oxidative stress, etc.) contributes to advanced atherosclerosis and increased cardiovascular risk. To decrease the morbidity and mortality of these patients due to cardiovascular causes, timely and efficient cardiovascular risk assessment is of huge importance. Cardiovascular risk assessment can be based on laboratory parameters, imaging techniques, arterial stiffness parameters, ankle-brachial index and 24 h blood pressure measurements. Newer methods include epigenetic markers, soluble adhesion molecules, cytokines and markers of oxidative stress. In this review, the authors present several non-invasive methods of cardiovascular risk assessment in patients with diabetes mellitus and chronic kidney disease.

Detection of early phenotype cardiac sarcoidosis by cardiovascular magnetic resonance

PURPOSE OF REVIEW

Cardiac sarcoidosis has high prevalence in sarcoidosis patients and contributes to significant morbidity and mortality. Early detection of cardiac sarcoidosis is essential to improving patients' symptoms and cardiovascular outcomes.

RECENT FINDINGS

Cardiovascular magnetic resonance imaging (CMR) is an excellent diagnostic modality for cardiac sarcoidosis. However, early phenotypes of cardiac sarcoidosis have more mild imaging phenotypes. These mild and sometimes subtle imaging phenotypes of cardiac sarcoidosis have lower diagnostic sensitivity and specificity for cardiac sarcoidosis by CMR when compared with more severe imaging phenotypes of cardiac sarcoidosis. In addition, many sarcoidosis patient cohorts frequently have heterogenous potential alternative etiologies for mild myocardial disease detected by mild late gadolinium enhancement (LGE) findings. In early phenotype cardiac sarcoidosis, analysis of the LGE pattern and location can improve the diagnostic specificity of these mild LGE findings.

SUMMARY

The current review focuses on the current strengths and challenges in CMR detection of early phenotypes of cardiac sarcoidosis by the LGE technique.

Sleep-disordered breathing and left ventricular scar on cardiac magnetic resonance: results of the Multi-Ethnic Study of Atherosclerosis

STUDY OBJECTIVES

The objectives of this study were to evaluate the independent association between sleep-disordered breathing (SDB) using overnight polysomnography and left ventricular (LV) scar using cardiac magnetic resonance (CMR) with late-gadolinium enhancement in a community-based cohort of the Multi-Ethnic Study of Atherosclerosis.

METHODS

Our analytical sample includes 934 participants from the fifth examination of the Multiethnic Study of Atherosclerosis who underwent both polysomnography and CMR. SDB was categorized as follows: no-SDB (apnea-hypopnea index [AHI] < 5 events/h), mild SDB (5 events/h ≤ AHI < 15 events/h), and moderate-severe SDB (AHI ≥ 15 events/h). LV scar was considered present if there was presence of scar on CMR (late-gadolinium enhancement > 0%). Logistic regression with multivariable adjustment for confounders (age, sex, race/ethnicity, body mass index, and cardiometabolic risk factors) was used to examine the independent association of SDB with LV scar. Confounders were identified using directed acyclic graphs.

RESULTS

The mean age of our sample was 67.0 ± 8.5 years (SD), with 49% (n = 461) females and a prevalence of SDB (AHI ≥ 5 events/h) of 63% (n = 590). LV scar was more prevalent in individuals with SDB (9.5%) versus those without SDB (3.8%; P < .01), and 88% of all LV scars were clinically unrecognized. After multivariable adjustment, both mild SDB and moderate-severe SDB were independently associated with LV scar (odds ratio, 2.53; 95% confidence interval, 1.13-5.64 and odds ratio, 2.31; 95% confidence interval, 1.01-5.24, respectively).

CONCLUSIONS

In a community-based cohort, SDB (including mild) is independently associated with a more than 2-fold increase in the odds of LV scar presence measured using CMR with late-gadolinium enhancement. Most LV scars were clinically unrecognized. The impact of SDB treatment on subclinical myocardial infarction needs to be investigated in future studies.

Cardiovascular Magnetic Resonance as Pathophysiologic Tool in Diabetes Mellitus

Diabetes mellitus can independently contribute to cardiovascular disease and represents a severe risk factor for premature development of cardiovascular disease. A three-fold higher mortality than the general population has been observed in type 1 diabetes mellitus whereas a two- to four-fold increased probability to develop cardiovascular disease has been observed in type 2 diabetes mellitus. Cardiovascular magnetic resonance, a non-radiative modality, is superior to all other modalities in detecting myocardial infarction. The main cardiovascular magnetic resonance sequences used include a) balanced steady-state free precession (bSSFP) for function evaluation; b) T2-W for oedema detection; c) T1 W for ischemia detection during adenosine stress; and d) late gadolinium enhanced T1-W images (LGE), evaluated 15 min after injection of paramagnetic contrast agent gadolinium, which permit the diagnosis of replacement fibrosis, which appears white in the middle of suppressed, nulled myocardium. Although LGE is the technique of choice for diagnosis of replacement fibrosis, it cannot assess diffuse myocardial fibrosis. The application of T1 mapping (native or pre contrast and post contrast) allows identification of diffuse myocardial fibrosis, which is not detectable my other means. Native T1 and Contrast-enhanced T1 mapping are involved in the extracellular volume fraction (ECV) calculation. Recently, 1H-cardiovascular magnetic resonance spectroscopy has been applied to calculate the amount of myocardial triglycerides, but at the moment it is not part of the routine assessment of diabetes mellitus. The multifaceted nature of cardiovascular magnetic resonance has the great potential of concurrent evaluation of function and myocardial ischemia/fibrosis in the same examination and represents an indispensable tool for accurate diagnosis of cardiovascular disease in diabetes mellitus.

Multimodality Imaging Assessment of Myocardial Fibrosis

Myocardial fibrosis, seen in ischemic and nonischemic cardiomyopathies, is associated with adverse cardiac outcomes. Noninvasive imaging plays a key role in early identification and quantification of myocardial fibrosis with the use of an expanding array of techniques including cardiac magnetic resonance, computed tomography, and nuclear imaging. This review discusses currently available noninvasive imaging techniques, provides insights into their strengths and limitations, and examines novel developments that will affect the future of noninvasive imaging of myocardial fibrosis.

Original Article--Value of Pathological Q Waves and Angiographic Collateral Grade in Patients Undergoing Coronary Chronic Total Occlusion Recanalization: Cardiac Magnetic Resonance Study

Background/aim

Successful coronary chronic total occlusion (CTO) revascularization was found by many studies to be associated with improved left ventricular (LV) systolic function and survival if evidence of viability is present. Little is known about the association of CTO revascularization in patients with electrocardiographic Q waves and improvement in angina burden as a measurement of health-related quality of life (HRQOL) afterwards.

Methods

In this study, 100 patients with single vessel CTO were included. Myocardial viability was tested by late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and 50 patients showed evidence of viability. Seattle Angina Questionnaire (SAQ) scores were used as a measure of HRQOL.

Results

Pathological Q waves were present in 48 patients (including 19 patients with viable CTO territory) out of 100 patients. Patients with Q waves tended to have worse Seattle Angina Questionnaire (SAQ) scores compared to those with no Q waves (31.2 ± 11.7 vs 45.3 ± 13.9 respectively, p = 0.002), worse LV systolic function and wall motion score index (WMSI) on CMR. They also had significantly less prevalence of viability (p < 0.001). Patients with Q waves and positive viability had lower SAQ scores (37.2 ± 10.1 vs 52.7 ± 13.2 respectively, p = 0.02), higher LVEF and lower WMSI. They also had well developed collateral grade (2.1 ± 1.03 vs 0.7 ± 0.82 respectively, p < 0.001). After successful percutaneous coronary intervention (PCI), in the viable LV group, presence of Q waves was not associated with better LV functional recovery, while those with higher collateral grades were more likely to have better LV functional recovery post CTO-PCI. Patients with Q waves and viable CTO territory showed significantly better SAQ scores compared to pre-PCI (87.3 ± 12.2 vs 37.2 ± 10.1 respectively, p < 0.001). For angina frequency, post–PCI score was 80.2 ± 7.9 compared to 39.2 ± 7.1 before PCI, p < 0.001). Multivariate regression analysis showed that pathological Q waves, Rentrop's collateral grade and the Canadian Cardiovascular Society (CCS) angina class before PCI were the most significant independent predictors of improved HRQOL as reflected by SAQ (OR for Q waves 7.83, 95% CI 1.62–18.91,p 0.003), (OR for Rentrop's collateral grade 8.31,95% CI 2.21–26.33, p < 0.001), (OR for CCS class 8.39, 95% CI 1.21–20.8, p 0.01).

Conclusion

Well-developed collateral circulation could independently predict LV functional recovery after CTO-PCI. Patients with Q waves and viable CTO territory tend to have higher CCS class before revascularization and get significant improvement of HRQOL after PCI. Other predictors of improved HRQOL are Rentrop's collateral grade and worse CCS class before PCI.