Prognostic impact of coronary microvascular dysfunction in patients with atrial fibrillation

BACKGROUND

Coronary microvascular dysfunction (CMD) is frequently observed in atrial fibrillation (AF), the most commonly sustained arrhythmia. Nevertheless, an in-depth prognostic significance of CMD in AF is lacking. We aimed to provide insight into the predictive impact of CMD assessed by a novel non-invasive coronary angiography-derived index of microcirculatory resistance (caIMR) for major adverse events (MACE) in AF patients.

METHOD

This study included patients with AF who underwent invasive coronary angiography due to suspected cardiac ischemia and did not exhibit obstructive epicardial coronary artery disease (≤50 % stenosis). The caIMR was prospectively evaluated, and the optimal cutoff value for predicting MACE was determined through ROC analysis.

RESULT

A total of 463 patients with AF were enrolled. During a median of 33 months of follow-up, 111 (23.97 %) patients had MACE endpoints. The best caIMR cutoff value was 39.28. In patients with MACE, both the mean caIMR and the prevalence of elevated caIMR (caIMR>39.28) were significantly higher compared to those without MACE. An elevated caIMR was linked to a higher risk of MACE (log-rank P < 0.001) and emerged as an independent predictor of clinical outcomes (HR: 4.029; 95 % CI: 2.529-6.418; P < 0.001). In addition, the risk of MACE was higher in high caIMR patients with non-paroxysmal AF (log-rank P < 0.001) and no catheter ablation (log-rank P < 0.001).

CONCLUSION

Elevated caIMR is common and showed a vital independent prognostic significance in AF patients. In addition to well-known risk factors, assessment of microvascular function can be a feasible approach for early prevention and a therapeutic target in AF patients.

Coronary Angiography-Derived Index of Microcirculatory Resistance Associated With New-Onset Atrial Fibrillation in Patients With STEMI

BACKGROUND

Coronary angiography-derived index of microcirculatory resistance (caIMR) can effectively assess coronary microvascular dysfunction in patients with ST-segment elevation myocardial infarction (STEMI). This study aimed to explore the role of caIMR in the occurrence of new-onset atrial fibrillation (NOAF) in patients with STEMI.

METHODS

This was a single-centre retrospective clinical observational study. Patients diagnosed with STEMI from September 2019 to December 2022 were included. caIMR was calculated using computational flow and pressure simulations. During admission, suspicious heart rhythm was recorded by electrocardiographic (ECG) monitoring, and NOAF was confirmed by an immediate 12-lead ECG.

RESULTS

A total of 739 patients were enrolled, including 57 (7.7) with NOAF. caIMR was significantly correlated with microvascular obstruction (R = 0.604; P < 0.001) and infarct size (R = 0.514; P < 0.001). After adjusting for potential confounding factors, the results showed that caIMR (odds ratio 1.058, 95% confidence interval 1.035-1.083; P < 0.001) was an independent risk factor for NOAF in patients with STEMI. Receiver operating characteristic analysis showed that the area under the curve of caIMR for predicting NOAF was 0.716. Compared with the caIMR < 27.35 U group, the caIMR ≥ 27.35 U group had higher high-sensitivity troponin T and N-terminal pro-B-type natriuretic peptide levels. When caIMR was added to the model, the reclassification and discriminant abilities improved significantly.

CONCLUSIONS

Higher caIMR was an independent risk factor for NOAF in patients with STEMI. The caIMR had high specificity and sensitivity for predicting NOAF in patients with STEMI. The integration of caIMR into clinical risk factors showed significantly increased predictability for NOAF in patients with STEMI.

Stress hyperglycemia ratio as a prognostic indicator for long-term adverse outcomes in heart failure with preserved ejection fraction

BACKGROUND

Recent studies highlighted that stress hyperglycemia ratio (SHR) is a potential predictor for future risk in heart failure (HF) patients. However, its implications specifically in HF with preserved ejection fraction (HFpEF) are not yet fully elucidated. We aimed to investigate the association between SHR and long-term clinical outcomes in HFpEF patients.

METHODS

HFpEF patients enrolled between 2015 and 2023, were followed (mean 41 months) for a composite outcome of all-cause, cardiovascular mortality, and HF rehospitalization. SHR was established as the ratio of acute-chronic glycemia from admission blood glucose and glycated hemoglobin. The optimal cut-off for SHR to predict outcomes based on event prediction was determined through ROC analysis, and the cutoff was identified at 0.99. The effect of SHR on adverse risk was examined through the Cox hazards and Kaplan-Meier survival methods. A Pearson correlation analysis was conducted to assess the relationship between SHR and the severity of HF, as indicated by N-terminal pro-brain natriuretic peptide (NT-proBNP) levels. Furthermore, the incremental prognostic value of SHR was further assessed by the integrated discrimination improvement (IDI) and the net reclassification improvement (NRI).

RESULTS

Among the 400 enrolled patients, 190 individuals (47.5%) encountered composite events over the 41-month follow-up period. SHR was significantly elevated in patients with events compared with those without (p < 0.001). All patients were stratified into high SHR (n = 124) and low SHR (n = 276) groups based on the SHR cutoff. The high SHR group had a significantly higher incidence of adverse events than the low SHR group (log-rank; p < 0.001). Additional analysis indicated a poorer prognosis in patients with low left ventricular EF (LVEF) levels (50 < LVEF < 60) and high SHR (SHR > 0.99) in comparison to the other groups (log-rank p < 0.001). In adjusted analysis, after accounting for age, sex, diabetes, and NT-proBNP, elevated SHR remained independently predictive of adverse outcomes (adjusted HR: 2.34, 95% CI 1.49-3.67; p < 0.001). Furthermore, adding SHR to a model with MAGGIC score provided an incremental improvement in predicting adverse events. Additionally, SHR displayed a slight correlation with NT-proBNP.

CONCLUSION

Elevated SHR was independently associated with an increased risk for composite events of all-cause, cardiovascular mortality, and HF readmission than those with lower SHR. SHR is a valuable tool for predicting and stratifying long-term adverse risks among HFpEF patients.

Prognostic value of coronary microvascular dysfunction in patients with aortic stenosis and nonobstructed coronary arteries

BACKGROUND

Patients with aortic valve stenosis have been postulated to have coronary microvascular dysfunction (CMD) contributing to the clinical symptoms and adverse outcomes. The coronary angiography (CAG)-derived index of microcirculatory resistance (caIMR) is proposed as a novel, less invasive and pressure-wire-free index to assess CMD. This study aimed to quantify CMD assessed by caIMR and investigate its prognostic impact in patients with aortic valve stenosis.

METHODS

This study included 77 moderate or severe aortic valve stenosis patients with no obstructive coronary disease (defined as having no stenosis more than 50% in diameter) who underwent caIMR measurement. CMD was defined by caIMR at least 25. Major adverse cardiovascular events (MACE) were the clinical outcomes during the median 40 months of follow-up.

RESULTS

The incidence of CMD was 47.7%. Seventeen MACE occurred during the follow-up duration. CMD was associated with an increased risk of MACE (log-rank P < 0.001) and an independent predictor of clinical outcomes [hazard ratio 5.467, 95% confidence interval (CI) 1.393-21.458; P = 0.015]. The receiver-operating characteristic (ROC) curve analysis demonstrated that caIMR could provide a significant predictive value for MACE in aortic valve stenosis patients (AUC 0.785, 95% CI 0.609-0.961, P < 0.001). In addition, the risk of MACE was higher in CMD patients with severe aortic valve stenosis (log-rank P < 0.001) and no aortic valve replacement (log-rank P = 0.003) than in other groups.

CONCLUSION

Aortic valve stenosis patients demonstrated markedly impaired caIMR. CMD assessed by caIMR increases the risk of MACE and is an independent predictor of adverse outcomes in aortic valve stenosis patients. This finding suggests that using caIMR in the clinical assessment may help identify high-risk groups and stimulate earlier intervention.

Coronary microvascular dysfunction and myocardial infarction with non-obstructive coronary arteries: Where do we stand?

In the past decade, scientific and clinical research has provided a translational perspective on myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA). MINOCA is characterized by clinical documentation of an acute MI but angiography shows no significant coronary artery obstruction (stenosis <50%). The prevalence of MINOCA is estimated to range from approximately 6 to 10% among MI patients, and those with this condition have a poor prognosis, experiencing high rates of mortality, rehospitalization, and socioeconomic burden. MINOCA represents a major unmet need in cardiovascular medicine, with uncertain clinical management. It is a complex condition that can be caused by various factors, including atherosclerosis, plaque rupture, coronary vasospasm, and microvascular dysfunction. Effective management of MINOCA depends on identifying the underlying mechanism of the infarction, thus a systematic diagnostic approach is recommended. Contemporary data shows that a significant number of patients exhibit structural and functional abnormalities in coronary microcirculation, which is referred to as coronary microvascular dysfunction (CMD). CMD plays a crucial role in patients with signs and symptoms of myocardial ischemia and non-obstructive coronary artery stenosis, including MINOCA. Furthermore, conducting a thorough evaluation of coronary function can have significant prognostic and therapeutic implications, since personalized patient management strategies based on this assessment have been shown to improve symptoms and prognosis. Therefore, an accurate and timely diagnosis of CMD is essential for effective patient management, which can be achieved through various invasive and non-invasive methods. This review will discuss the pathophysiological understanding, current diagnostic techniques, and management strategies of patients with MINOCA and CMD.

Screening and verifying the mutations in the LDLR and APOB genes in a Chinese family with familial hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder. The primary objective of this study was to identify the major pathogenic mutations in a Chinese family with FH.

METHODS

Whole-genome sequencing (WGS) was used to identify variants of FH-related genes, including low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9). Bioinformatics software was used to predict signal peptides, transmembrane structures, and spatial construction information of the mutated sequences. Western blotting was performed on the mutant protein to determine the presence of the major structural domains of the LDLR. The PCSK9 and APOB genes were screened and analyzed. Moreover, the proband and his brother were treated with a PCSK9 inhibitor for 1 year, and the effect of the treatment on lipid levels was assessed.

RESULTS

WGS revealed two potentially pathogenic mutations in the LDLR gene. One was a novel mutation, c.497delinsGGATCCCCCAGCTGCATCCCCCAG (p. Ala166fs), and the other was a known pathogenic mutation, c.2054C>T (p. Pro685Leu). Bioinformatics prediction and in vitro experiments revealed that the novel mutation could not be expressed on the cell membrane. Numerous gene variants were identified in the APOB gene that may have a significant impact on the family members with FH. Thus, it is suggested that the severe manifestation of FH in the proband primarily resulted from the cumulative genetic effects of variants in both LDLR and APOB. However, a subsequent study indicated that treatment with a PCSK9 inhibitor (Evolocumab) did not significantly reduce the blood lipid levels in the proband or his brother.

CONCLUSIONS

The cumulative effect of LDLR and APOB variants was the primary cause of elevated blood lipid levels in this family. However, PCSK9 inhibitor therapy did not appear to be beneficial for the proband. This study emphasizes the importance of genetic testing in determining the most suitable treatment options for patients with FH.

Association between the atherogenic index of plasma and adverse long-term prognosis in patients diagnosed with chronic coronary syndrome

BACKGROUND

The Atherogenic Index of Plasma (AIP) is a newly identified biomarker associated with lipid metabolism, demonstrating significant prognostic capabilities in individuals diagnosed with cardiovascular disease. However, its impact within the context of chronic coronary syndromes (CCS) remains unexplored. Thus, the present investigation sought to examine the potential association between AIP levels and long-term clinical outcomes in patients diagnosed with CCS.

METHODS

A total of 404 patients diagnosed with CCS and who underwent coronary angiography were included in this study. The AIP index was calculated as log (triglycerides / high-density lipoprotein-cholesterol). The patients were categorized into four groups based on their AIP values: Q1 (< -0.064), Q2 (-0.064 to 0.130), Q3 (0.130 to 0.328), and Q4 (> 0.328). The occurrence of major adverse cardiovascular events (MACE) was monitored during the follow-up period for all patients. Cox regression analysis and Kaplan-Meier curve analysis were employed to examine the relationship between AIP and MACE. Furthermore, ROC analysis was utilized to determine the optimal cut-off value of AIP for predicting clinical MACE.

RESULTS

During the median 35 months of follow-up, a total of 88 patients experienced MACE. Notably, the group of patients with higher AIP values (Q4 group) exhibited a significantly higher incidence of MACE compared to those with lower AIP values (Q1, Q2, and Q3 groups) (31.7% vs. 16.8%, 15.7%, and 23.0% respectively; P = 0.023). The Kaplan-Meier curves illustrated those patients in the Q4 group had the highest risk of MACE relative to patients in the other groups (log-rank P = 0.014). Furthermore, the multivariate Cox regression analysis demonstrated that individuals in the Q4 group had a 7.892-fold increased risk of MACE compared to those in the Q1 group (adjusted HR, 7.892; 95% CI 1.818-34.269; P = 0.006). Additionally, the ROC curve analysis revealed an optimal AIP cut-off value of 0.24 for predicting clinical MACE in patients with CCS.

CONCLUSION

Our data indicate, for the first time, that AIP is independently associated with poor long-term prognosis in patients suffering from CCS. The optimal AIP cut-off value for predicting clinical MACE among CCS patients was 0.24.

Prognostic Significance of Coronary Microvascular Dysfunction in Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

The prognostic impact of coronary microvascular dysfunction (CMD) has been scarcely addressed in heart failure with preserved ejection fraction (HFpEF). This study investigated the prevalence and prognostic significance of CMD as measured by a novel pressure wire-free coronary angiography-derived index of microcirculatory resistance (caIMR) on clinical outcomes.

METHODS

Patients diagnosed with HFpEF from 2019 to 2021 were enrolled retrospectively. caIMR was used to quantify microvascular function, and patients were categorised into 2 groups based on their caIMR. The primary end points were composite of all-cause death and heart failure rehospitalisation.

RESULTS

Of 137 HFpEF patients, CMD (defined as caIMR ≥ 25) was present in 88 patients (64.2%). Forty-five patients (32.8%) experienced composite events during a mean follow-up of 15 months. Compared with patients with caIMR < 25, those with caIMR ≥ 25 had a notably higher incidence of composite events (16.3% vs 42.0%; P = 0.002). On survival analysis, patients with caIMR ≥ 25 demonstrated a worse prognosis than those with caIMR < 25 for composite events (P = 0.006). Patients with caIMR ≥ 25 in multiple coronary arteries showed a trend to worse outcome than those with caIMR ≥ 25 in a single coronary artery (log-rank P = 0.056). In adjusted analysis, caIMR ≥ 25 was independently predictive of adverse outcomes (adjusted hazard ratio 2.93, 95% confidence interval [CI] 1.28-6.70; P = 0.010). caIMR displayed a significant predictive power for adverse event prediction (area under the receiver operating characteristic curve 0.767, 95% CI 0.677-0.858; P < 0.001).

CONCLUSIONS

CMD is highly prevalent and is an independent predictor of adverse outcomes in HFpEF patients. Assessment of CMD may identify high-risk patients early for intensified treatment and risk-factor management.

The prognostic value of CZT SPECT myocardial blood flow (MBF) quantification in patients with ischemia and no obstructive coronary artery disease (INOCA): a pilot study

BACKGROUND

Despite the demonstrated adverse outcome, it is difficult to early identify the risks for patients with ischemia and no obstructive coronary artery disease (INOCA). We aimed to explore the prognostic potential of CZT SPECT in INOCA patients.

METHODS

The study population consisted of a retrospective cohort of 118 INOCA patients, all of whom underwent CZT SPECT imaging and invasive coronary angiography (ICA). Dynamic data were reconstructed, and MBF was quantified using net retention model. Major adverse cardiovascular events (MACEs) were defined as cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, heart failure, late coronary revascularization, or hospitalization for unstable angina.

RESULTS

During a median follow-up of 15 months (interquartile range (IQR) 11-20), 19 (16.1%) MACEs occurred; both stress myocardial blood flow (sMBF) ([Formula: see text]) and coronary flow reserve (CFR) ([Formula: see text]) were significantly lower in the MACE group. Optimal thresholds of sMBF<3.16 and CFR<2.52 were extracted from the ROC curves, and both impaired sMBF (HR: 15.08; 95% CI 2.95-77.07; [Formula: see text]) and CFR (HR: 6.51; 95% CI 1.43-29.65; [Formula: see text]) were identified as prognostic factors for MACEs. Only sMBF<3.16 (HR: 11.20; 95% CI 2.04-61.41; [Formula: see text]) remained a robust predictor when sMBF and CFR were integrated considered. Compared with CFR, sMBF provides better prognostic model discrimination and reclassification ability (C-index improvement = 0.06, [Formula: see text]; net reclassification improvement (NRI) = 0.19; integrated discrimination improvement (IDI) = 0.10).

CONCLUSION

The preliminary results demonstrated that quantitative analysis on CZT SPECT provides prognostic value for INOCA patients, which may allow the stratification for early prevention and intervention.

Association between the triglyceride-glucose index and the presence and prognosis of coronary microvascular dysfunction in patients with chronic coronary syndrome

BACKGROUND

Coronary microvascular dysfunction (CMD) is a strong determinant of prognosis in patients with chronic coronary syndrome (CCS). The triglyceride-glucose index (TyG index), an alternative method to evaluate insulin resistance, is positively correlated with the incidence and adverse outcomes of cardiovascular diseases. However, the relationship between the TyG index and the presence and prognosis of CMD in CCS patients has not been investigated. Therefore, we aimed to evaluate the association between the TyG index and the presence and clinical outcomes of CMD among CCS patients.

METHODS

CCS patients who underwent coronary angiography between June 2015 to June 2019 were included. The TyG index was calculated as Ln[fasting triglycerides (mg/dL) × fasting blood glucose (mg/dL)/2]. Coronary angiography‑derived index of microvascular resistance (caIMR) was used to measure microvascular function, and CMD was defined as caIMR ≥ 25U. Patients with CMD were divided into three groups (T1, T2, and T3 groups) according to TyG tertiles. The primary endpoint was major adverse cardiac event (MACE).

RESULTS

Of 430 CCS patients, 221 patients had CMD. CMD patients had significantly higher TyG index than those without CMD. Sixty-three MACE was recorded during the follow-up duration among CMD patients, and the incidence rate of MACE was higher in the T3 group compared to T1/T2 groups (39.2% vs. 20.5% vs. 25.7%; P = 0.035). Multivariable logistic regression analysis showed that the TyG index was an independent predictor of CMD (OR, 1.436; 95% CI, 1.014-2.034; P = 0.042). Compared to the T1 group, the T3 group strongly correlated with the risk of MACE in CMD patients even after adjusting for additional confounding risk factors (HR, 2.132; 95%CI, 1.066-4.261; P = 0.032).

CONCLUSION

TyG index is significantly associated with the risk of CMD, and it is an independent predictor of MACE among CMD patients with CCS. This study suggests that the TyG index has important clinical significance for the early prevention and risk stratification of CMD.

2023 Chinese expert consensus on the impact of COVID-19 on the management of cardiovascular diseases

The primary site of infection in COVID-19 exhibit is the respiratory system, but multiple organ systems could be affected. The virus could directly invade cardiomyocytes. Alternatively, cytokine storm could lead to myocardial injury. More importantly, the management of existing cardiovascular diseases must be re-examined in COVID-19 due to, for example, interaction between antiviral agents and with a wide variety of pharmacological agents. The Branch of Cardiovascular Physicians of Chinese Medical Doctor Association organized a panel of experts in cardiovascular and related fields to discuss this important issue, and formulated the "2023 Chinese Expert Consensus on the Impact of COVID-19 on the Management of Cardiovascular Diseases." The Consensus was drafted on the basis of systematic review of existing evidence and diagnosis and treatment experience, and covers three major aspects: myocardial injury caused by COVID-10 and COVID-19 vaccine, the impact of COVID-19 on patients with cardiovascular disease, and the impact of COVID-19 on the cardiovascular system of healthy people, and rehabilitation guidance recommendations. The Consensus involves 11 core clinical issues, including incidence, pathogenesis, clinical manifestations, treatment strategies, prognosis, and rehabilitation. It is our hope that this Consensus will provide a practical guidance to cardiologists in the management of cardiovascular diseases in the new era of COVID-19 pandemic.

Prognostic value of combined coronary angiography-derived IMR and myocardial perfusion imaging by CZT SPECT in INOCA

BACKGROUND

A significant proportion of ischemia with non-obstructive coronary artery disease (INOCA) demonstrate coronary microvascular dysfunction (CMD), a condition associated with abnormal myocardial perfusion imaging (MPI) and adverse outcomes. Coronary angiography-derived index of microvascular resistance (caIMR) is a novel non-invasive technique to assess CMD. We aimed to investigate the prognostic value of combined caIMR and MPI by CZT SPECT in INOCA patients.

METHODS

Consecutive 151 patients with chest pain and < 50% coronary stenosis who underwent coronary angiography and MPI within 3 months were enrolled. caIMR was calculated by computational pressure-flow dynamics. CMD was defined as caIMR ≥ 25. The endpoint was major adverse cardiac events (MACE: cardiovascular death, nonfatal myocardial infarction, revascularization, angina-related rehospitalization, heart failure, and stroke).

RESULTS

Of all INOCA patients, CMD was present in 93 (61.6%) patients. The prevalence of abnormal MPI was significantly higher in CMD compared with non-CMD patients (40.9% vs 13.8%, P < .001). CMD showed a higher risk of MACE than non-CMD patients. Patients with both CMD and abnormal MPI had the worst prognosis, followed by patients with CMD and normal MPI (log-rank P < .001). Cox regression analysis identified CMD (HR 3.121, 95%CI 1.221-7.974, P = .017) and MPI (HR 2.704, 95%CI 1.030-7.099, P = .043) as predictive of MACE. The prognostic value of INOCA patients enhanced significantly by adding CMD and MPI to the model with clinical risk factors (AUC = 0.777 vs 0.686, P = .030).

CONCLUSION

caIMR-derived CMD is associated with increased risk of MACE among INOCA patients. Patients with abnormalities on both caIMR and MPI had the worse outcomes.

Prognostic implication of coronary slow flow assessed by cTFC in patients with myocardial infarction with Non-obstructive coronary arteries

BACKGROUND

Coronary slow flow (CSF) is common and linked to worse cardiovascular events and life-threatening arrhythmias. However, the clinical implication of CSF among myocardial infarction with the non-obstructive coronary artery (MINOCA) has never been studied. We aimed to evaluate the impact of CSF on the MINOCA population.

METHODS

Patients diagnosed with MINOCA were consecutively selected. The corrected TIMI frame count (cTFC) was used to evaluate the coronary flow. CSF was defined as cTFC greater than 27 frames per second (FPS) in any of the three coronary arteries. Major adverse cardiovascular events (MACE) are the primary endpoint. Cox regression analysis was used to evaluate the association between CSF and MACE.

RESULTS

A total of 158 patients with MINOCA were enrolled, of which 54 (34.2%) patients had CSF. Forty incidents of MACE occurred during the median 28 months of follow-up. The MACE incidence was higher among patients who presented with CSF than the normal coronary flow patients (35.2% vs. 20.2%, p = 0.040). In the Kaplan-Meier analysis, CSF patients had significantly higher rates of MACE (log-rank P = 0.034). Multivariate Cox regression analysis showed that CSF was an independent predictor linked to an increased hazard of MACE (adjusted HR, 2.76; 95% CI, 1.34-5.67; P = 0.006).

CONCLUSION

The presence of CSF is associated with a higher risk of adverse events and is an independent predictor of clinical outcomes among patients with MINOCA. This result suggests that CSF might serve as a robust tool to stratify MINOCA patients.

Association of stress hyperglycemia ratio and poor long-term prognosis in patients with myocardial infarction with non-obstructive coronary arteries

BACKGROUND

Stress hyperglycemia ratio (SHR) is a novel biomarker of true acute hyperglycemia condition and is associated with a worse prognosis in patients with myocardial infarction (MI). However, the effects of SHR in the setting of MI with non-obstructive coronary arteries (MINOCA) have not been investigated. This study aimed to explore the association between SHR and long-term clinical outcomes among MINOCA patients.

METHODS

A total of 410 MINOCA patients were included in the final analysis of this study. The patients were divided into three groups based on the SHR tertiles: [SHR1 group (SHR ≤ 0.73), (n = 143); SHR2 group (SHR 0.73-0.84), n = 131; and SHR3 group (SHR ≥ 0.84), n = 136]. Follow-up for major adverse cardiovascular events (MACE) was conducted on all patients. Cox regression and Kaplan-Meier curve analysis were used to evaluate the relationship between SHR and MACE. The receiver operating curve (ROC) analysis was applied to obtain the optimal cut-off value of SHR for predicting clinical MACE.

RESULTS

A total of 92 patients developed MACE during the mean 34 months of follow-up. A significant increase in MACE was observed in the SHR3 group compared to the SHR1 and SHR2 groups (35.3% vs. 15.4% and 16.8%, respectively; P < 0.001). The Kaplan-Meier curves demonstrate that SHR3 patients had the highest MACE risk compared to SHR1 and SHR2 patients (log-rank P < 0.001). In addition, when both SHR tertiles and diabetes status were considered, those with SHR3 and diabetes had the highest hazard of MACE (log-rank P < 0.001). Multivariate Cox regression analysis showed that the SHR3 is associated with a 2.465-fold increase in the risk of MACE (adjusted HR, 2.465; 95% CI 1.461-4.159, P = 0.001). The ROC curve analysis showed that the optimal SHR cut-off value for predicting clinical MACE among MINOCA was 0.86.

CONCLUSION

Our data indicates, for the first time, that SHR is independently associated with poor long-term prognosis in patients suffering from MINOCA. The optimal SHR cut-off value for predicting clinical MACE among MINOCA patients was 0.86. These findings suggest that SHR may play a potential role in the cardiovascular risk stratification of the MINOCA population.

Effect of nonobstructive coronary stenosis on coronary microvascular dysfunction and long-term outcomes in patients with INOCA

BACKGROUND

Ischemic pain with no-obstructive coronary artery (INOCA) is clinically significant and defined by nonobstructive coronary stenosis <50%. Coronary microvascular dysfunction (CMD) is a relevant cause associated with adverse outcomes.

OBJECTIVES

Investigated the effect of no-stenosis (0% stenosis) and non-obstructive (0% < stenosis < 50%) on the prognostic impact of CMD in INOCA.

METHOD

A retrospective study assessed the coronary microvascular function in 151 INOCA patients who underwent invasive angiography by the coronary angiography-derived index of microcirculation-resistance (caIMR). CZT-SPECT was performed to evaluate myocardial perfusion imaging (MPI) abnormalities. Chi-square test/Fisher exact test, Student t-test, Kaplan-Meier curve, and Uni-multivariable Cox proportional models were used for analysis. Clinical outcomes were major adverse cardiovascular events (MACE) during a median follow-up of 35 months.

RESULT

No-stenosis was present in 71 (47%) INOCA patients, and 80 (53%) were with nonobstructive. CMD (caIMR ≥ 25) was more prevalent in patients with no-stenosis than nonobstructive (76.1% vs. 48.8%, p = .001), along with abnormal MPI (39.4% vs. 22.5%, p = .024). The MACE rates were not different between no-stenosis and nonobstructive stenosis. CMD showed an increased risk of MACE for all INOCA. No-stenosis with CMD had the worst prognosis. Cox regression analysis identified CMD and abnormal MPI as predictors of MACE in all INOCA and patients with no-stenosis. However, no-stenosis and nonobstructive stenosis were not predictors of MACE in INOCA.

CONCLUSION

CMD was more frequently present in INOCA with no-stenosis. However, there was no difference in long-term clinical outcomes between no-stenosis and nonobstructive stenosis. CMD could independently predict poor outcomes in INOCA, particularly in patients with no-stenosis.

Prognostic value of coronary microvascular dysfunction assessed by coronary angiography-derived index of microcirculatory resistance in diabetic patients with chronic coronary syndrome

Background

Coronary microvascular dysfunction (CMD) is common and is associated with unfavorable cardiovascular events in patients with diabetes mellitus (DM). Coronary angiography-derived index of microcirculatory resistance (caIMR) is a recently developed wire- and hyperemic agent-free method to assess CMD. We aimed to investigate the prognostic impact of CMD assessed by caIMR on clinical outcomes in patients with DM and chronic coronary syndrome (CCS).

Methods

CCS patients who underwent coronary angiography between June 2015 to May 2018 were included. Coronary microvascular function was measured by caIMR, and CMD was defined as caIMR ≥ 25U. The primary endpoint was major adverse cardiac events (MACE). Kaplan-Meier analysis and Cox proportional hazards models were used to assess the relationship between caIMR and the risk of MACE.

Results

Of 290 CCS patients, 102 patients had DM. Compared with non-diabetic patients, CMD (caIMR ≥ 25U) was higher among DM patients (57.8% vs. 38.3%; p = 0.001). During a mean 35 months follow-up, 40 MACE had occurred. Patients with caIMR ≥ 25 had a higher rate of MACE than patients with caIMR < 25 (20.6% vs. 8.2%, p = 0.002). Of these, the MACE rate was higher among DM patients with caIMR ≥ 25 than those with caIMR < 25 (33.9% vs. 14.0%; p = 0.022). In multivariable Cox analysis, caIMR ≥ 25 was independently associated with MACE in the DM patients but not in non-DM patients (HR, 2.760; 95% CI, 1.066–7.146; P = 0.036).

Conclusion

CMD assessed by caIMR was common and is an independent predictor of MACE among diabetic patients with CCS. This finding potentially enables a triage of higher-risk patients to more intensive therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01653-y.

A Left Ventricular Mechanical Dyssynchrony-Based Nomogram for Predicting Major Adverse Cardiac Events Risk in Patients With Ischemia and No Obstructive Coronary Artery Disease

Background

The risk stratification of patients with ischemia and no obstructive coronary artery disease (INOCA) remains suboptimal. This study aims to establish a left ventricular mechanical dyssynchrony (LVMD)-based nomogram to improve the present situation.

Methods

Patients with suspected coronary artery disease (CAD) were retrospectively enrolled and divided into three groups: normal (stenosis &lt;50%, without myocardial ischemia), INOCA (stenosis &lt;50%, summed stress score &gt;4, summed difference score ≥2), and obstructive CAD (stenosis ≥50%). LVMD was defined by ROC analysis. INOCA group were followed up for the occurrence of major adverse cardiac events (MACEs: cardiovascular death, non-fatal myocardial infarction, revascularization, stroke, heart failure, and hospitalization for unstable angina). Nomogram was established using multivariate Cox regression analysis.

Results

Among 334 patients (118 [35.3%] INOCA), LVMD parameters were significantly higher in INOCA group versus normal group but they did not differ between obstructive CAD groups. In INOCA group, 27 (22.9%) MACEs occurred during a 26-month median follow-up. Proportion of LVMD was significantly higher with MACEs under both stress (63.0% vs. 22.0%, P &lt; 0.001) and rest (51.9% vs. 20.9%, P = 0.002). Kaplan–Meier analysis revealed significantly higher rate of MACEs (stress log-rank: P = 0.002; rest log-rank: P &lt; 0.001) in LVMD patients. Multivariate Cox regression analysis showed that stress LVMD (HR: 3.82; 95% CI: 1.30–11.20; P = 0.015) was an independent predictor of MACEs. The internal bootstrap resampling approach indicates that the C-index of nomogram was 0.80 (95% CI: 0.71–0.89) and the AUC values for 1 and 3 years of risk prediction were 0.68 (95% CI: 0.46–0.89) and 0.84 (95% CI: 0.72–0.95), respectively.

Conclusion

LVMD-based nomogram might provide incremental prognostic value and improve the risk stratification in INOCA patients.

Metabolic syndrome and the risk of adverse cardiovascular events in patients with myocardial infarction with non-obstructive coronary arteries

BACKGROUND AND AIMS

Metabolic syndrome (MeS) is recognized as a significant predictor of poor outcomes in coronary artery disease. However, its prognostic implications in myocardial infarction with non-obstructive coronary arteries (MINOCA) have not been examined. We aimed at investigating the role of MeS on the clinical outcomes in MINOCA patients.

METHODS AND RESULTS

Patients diagnosed with MINOCA between 2015 and 2019 were included. MeS was defined according to modified NCEP-ATPIII criteria. The primary endpoint was major adverse cardiovascular events (MACE). Cox regression analysis was used to evaluate the correlation between MeS and the hazard of MACE. The integrated discrimination improvement (IDI) and net reclassification index (NRI) were performed to assess MeS incremental predictive value. Of 281 MINOCA patients, 83 (29.5%) patients satisfied the MeS criteria. During a median follow-up duration of 28 months, MINOCA patients with MeS had a notably higher rate of MACE than those without MeS (30.1% vs. 17.6%, respectively P = 0.020). Cox regression analysis revealed that MeS was associated with an increased hazard of MACE (adjusted HR 2.126; 95% CI: 1.193-3.787, P = 0.010). When each component of MeS was analyzed as a categorized variable separately, only high fasting blood glucose and BMI ≥25 kg/m² were associated with an increased hazard of MACE. Moreover, MeS had an incremental predictive ability for MACE when added to a model with clinical risk factors.

CONCLUSION

MeS is relatively common in patients with MINOCA. The presence of MeS significantly increased the hazard of MACE among the MINOCA population.

Elevated levels of sIL-2R, TNF-α and hs-CRP are independent risk factors for post percutaneous coronary intervention coronary slow flow in patients with non-ST segment elevation acute coronary syndrome

To evaluate the association between circulating levels of inflammatory cytokines and the occurrence of post-percutaneous coronary intervention (PCI) coronary slow flow (CSF) in patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS). CSF after PCI commonly occurs and implies poor outcomes, while the determinants of post-PCI CSF in patients with NSTE-ACS remain controversial. In this multicenter case control study, 176 patients diagnosed with NSTE-ACS and with post-PCI CSF occurred composed of CSF group, while 352 matched NSTE-ACS patients composed control group. Corrected thrombolysis in myocardial infarction frame count (cTFC), circulating levels of inflammatory cytokines and PCI related parameters were analyzed using Logistic regression models. Among 528 patients with median age of 67 (59-76) and male proportion of 65.5%, 176 (35.0%) patients had occurrence of post-PCI CSF defined as cTFC ≥ 24. Patients with CSF presented more intense inflammatory activity revealed by higher levels of white blood cell, high-sensitivity C-reactive protein (hs-CRP), interleukin-1ß (IL-1ß), soluble IL-2 receptor (sIL-2R), IL-6, IL-8, IL-10 and tumor necrosis factor-α (TNF-α), while PCI related parameters were comparable. Correlation analysis showed cTFC was positively correlated with those inflammatory cytokines. Logistic regression model indicates that hs-CRP (odds ratio (OR) = 3.038, 95% confidence interval (CI) 1.545-5.975), sIL-2R (OR = 2.103, 95% CI 1.959-4.026) and TNF-α (OR = 3.708, 95% CI 1.426-9.641) were valuable predictors for CSF occurrence. Elevated circulating levels of inflammatory cytokine including hs-CRP, sIL-2R and TNF-α rather than PCI related parameters could predict post-PCI CSF in patients with NSTE-ACS.

Association between Initial Serum Total Bilirubin and Clinical Outcome in Myocardial Infarction with Non-Obstructive Coronary Arteries

Background: Liver function parameters, particularly serum total bilirubin (TB), are closely associated with cardiovascular diseases. However, the impact of serum TB among patients with myocardial infarction and non-obstructive coronary (MINOCA) remains unknown. Our study investigated the relationship between serum TB at admission and long-term adverse clinical outcomes in MINOCA patients. Methods: A total of 273 consecutive MINOCA patients were categorized into low and high serum TB groups based on the optimal cut-off of 0.9 mg/dl. The primary endpoint was major adverse cardiovascular events (MACE), including cardiac death, non-fatal MI, heart failure, and angina rehospitalization. Receiver-operating characteristic, Cox regression, and Kaplan-Meier analyses were used to evaluate the association of high serum TB with cardiovascular outcomes. Results: High serum TB was found in 68 (24.9%) patients. The incidence of MACE was higher in the high TB group than in the low TB group after a median follow-up of 28 months (30.9 vs. 17.1%, P=0.015). The Kaplan-Meier curve analysis also indicated that patients in the high TB group had a higher risk of developing MACE (log-rank P=0.023). Cox regression analysis showed that high serum TB (>0.9mg/dl) significantly correlated with increased MACE risk (HR=1.90, 95%CI: 1.12-3.22, P=0.018). After adjusting for numerous clinical variables, the high serum TB remained significantly associated with an increased risk of MACE (HR=2.04, 95%CI: 1.05-3.94, P=0.034). Conclusion: High initial serum TB (>0.9mg/dl) is a robust predictor of poor clinical outcomes among MINOCA patients. In clinical settings, assessing serum TB at admission may help identify high-risk patients presenting with MINOCA.

Prognostic impact of coronary microvascular dysfunction assessed by caIMR in overweight with chronic coronary syndrome patients

OBJECTIVE

Coronary microvascular dysfunction (CMD) may associate with adverse cardiovascular events in obese patients. Coronary angiography-derived index of microcirculatory resistance (caIMR) is proposed as a less-invasive and pressure-wire-free index to assess CMD. We aimed to investigate the impact of coronary microvascular function assessed by caIMR in patients with overweight and chronic coronary syndrome (CCS).

METHODS

CCS patients who underwent coronary angiography between 2015 to 2018 were included. Overweight was defined as BMI≥24.0kg/m². Impaired coronary microvascular function was defined as caIMR≥25U. The patients were classified according to BMI and caIMR. The primary endpoint was major adverse cardiac events (MACE). Kaplan-Meier and Cox regression analyses evaluated the association between caIMR and MACE.

RESULTS

Two hundred and eighty-two CCS patients were enrolled. Among these, 169 (59.93%) were overweight. Impaired coronary microvascular function was higher in overweight patients than in patients with normal weight (49.70% vs. 38.05%; P=0.035). During 35 months of follow-up, 33 MACE had occurred. Among the total CCS population, MACE was higher in patients with high caIMR than in low caIMR (18.11% vs. 6.45%, P=0.003). In subgroups analysis, MACE was higher in overweight patients with high caIMR than low caIMR (20.24% vs. 7.06%, P=0.014), while there were no significant differences in normal-weight patients. Multivariate Cox analysis demonstrated that caIMR≥25 was independently associated with MACE in overweight patients (HR, 2.87; 95% CI, 1.12-7.30; P=0.027) but not in the normal-weight patients. In addition, caIMR showed a significant predictive value for adverse outcomes in overweight patients and provided an incremental prediction when added to a prediction model with BMI.

CONCLUSIONS

Impaired coronary microvascular function assessed by caIMR was common and is an independent predictor of MACE in overweight patients with CCS.

FT4/FT3 ratio: A novel biomarker predicts coronary microvascular dysfunction (CMD) in euthyroid INOCA patients

BACKGROUND

Ischemia and no obstructive coronary artery disease (INOCA) patients who presented coronary microvascular dysfunction (CMD) demonstrate a poor prognosis, yet the risk factors for CMD remain unclear. Subtle changes in thyroid hormone levels within the normal range, especially the free thyroxine (FT4)/free triiodothyronine (FT3) ratio, have been shown to regulate the cardiovascular system. This prospective study investigated the correlation between FT4/FT3 ratio and CMD in euthyroid patients with INOCA.

METHODS

This prospective study (www.chictr.org.cn/, ChiCTR2000037112) recruited patients with myocardial ischemia symptoms who underwent both coronary angiography (CAG) and myocardial perfusion imaging (MPI) with dynamic single-photon emission computed tomography (D-SPECT). INOCA was defined as coronary stenosis< 50% and CMD was defined as coronary flow reserve (CFR)<2.5. All patients were excluded from abnormal thyroid function and thyroid disease history.

RESULTS

Among 71 INOCA patients (15 [21.1%] CMD), FT4 and FT4/FT3 ratio in CMD group were significantly higher and both showed significantly moderate correlation with CFR (r=-0.25, p=0.03; r=-0.34, p=0.003, respectively). The ROC curve revealed that FT4/FT3 ratio had the highest efficacy for predicting CMD with an optimized cutoff value>3.39 (AUC 0.78, p<0.001, sensitivity, 80.0%; specificity, 71.4%). Multivariate logistic regression showed that FT4/FT3 ratio was an independent predictor of CMD (OR 7.62, 95% CI 1.12-51.89, p=0.038, P for trend=0.006).

CONCLUSION

In euthyroid INOCA patients, increased FT4/FT3 ratio levels are associated with the occurrence of CMD, presenting a novel biomarker for improving the risk stratification.

Prognostic value of myocardial perfusion imaging with D-SPECT camera in patients with ischemia and no obstructive coronary artery disease (INOCA)

BACKGROUND

Myocardial perfusion imaging (MPI) with a novel D-SPECT camera maintains excellent prognostic value compared to conventional SPECT. However, information about the relationship between D-SPECT MPI and the prognosis in patients with ischemia and no obstructive coronary artery disease (INOCA) is limited. The objective of this study was to evaluate the prognostic value of MPI with D-SPECT in INOCA and obstructive coronary artery disease (CAD) patients.

METHODS

All consecutive patients with suspected CAD and without prior CAD who underwent D-SPECT MPI and invasive coronary angiography within 3 months were considered. INOCA and obstructive CAD were defined as < 50% and ≥ 50% coronary stenosis, respectively. Patients were followed-up for the occurrence of major adverse cardiac events (MACE: cardiovascular death, nonfatal myocardial infarction, revascularization, stroke, heart failure and angina-related rehospitalization).

RESULTS

Among 506 patients, 232 (45.8%) were INOCA patients. A total of 33.2% of the INOCA patients had abnormal D-SPECT MPI, whereas 77.7% of the obstructive CAD patients had abnormal D-SPECT MPI. In both groups, patients with abnormal D-SPECT MPI demonstrated higher MACE rates and lower survival free of MACE. In addition, patients with INOCA and abnormal D-SPECT MPI had a poor prognosis similar to that of the obstructive CAD patients. Cox regression analysis showed that the risk-adjusted hazard ratios for abnormal D-SPECT MPI were 2.55 [1.11-5.87] and 2.06 [1.03-4.10] in the INOCA and obstructive CAD patients, respectively.

CONCLUSIONS

D-SPECT MPI provides excellent prognostic information, with a more severe prognosis in patients with abnormal D-SPECT MPI. INOCA patients with abnormal D-SPECT MPI experience a poor prognosis similar to that of patients with obstructive CAD.

Prognostic Significance of Uric Acid in Patients with Obstructive and Nonobstructive Coronary Artery Disease Undergoing D-SPECT

Purpose

The association of serum uric acid (SUA) levels with cardiovascular outcomes in patients with coronary artery disease (CAD) has been extensively studied and yielded conflicting results. We aimed to investigate whether the severity of coronary stenosis and ischemia influences the prognostic impact of SUA levels in patients with CAD undergoing D-SPECT.

Patients and Methods

This study consecutively included patients who were admitted for CAD in Shanghai Tenth People's Hospital between June 2014 and August 2018, had complete SUA data and underwent both coronary angiography and D-SPECT within 3 months. Hyperuricemia was defined as an SUA level of >7 mg/dL in men and >6 mg/dL in women. The primary outcome was major adverse cardiovascular events (MACE), defined as a composite of cardiac death, unplanned coronary revascularization, nonfatal myocardial infarction, ischemic stroke, heart failure, and angina-related hospitalization.

Results

A total of 695 patients were included, of whom 432 (62.2%) presented with obstructive CAD and 117 (16.8%) had hyperuricemia. During a median follow-up of 26 months, the incidence rates of MACE in patients with hyperuricemia and normouricemia were 15.2% and 21.1%, respectively. After a multivariable adjustment, hyperuricemia was significantly associated with an increased risk of MACE (HR: 1.39, 95% CI: 1.03-1.87, p = 0.033) when compared with normouricemia. When repeating the primary analysis in patients with and without obstructive CAD, we showed that hyperuricemia was independently associated with an 80% increased risk of MACE among patients with nonobstructive CAD (HR: 1.80, 95% CI: 1.04-3.11, p = 0.035), while such a significant association was not found among those with obstructive CAD (HR: 1.18, 95% CI: 0.82-1.72, p = 0.373). Moreover, we uncovered a U-shaped and linear trajectory of SUA levels with MACE in the obstructive and nonobstructive CAD, respectively. The sex-specific analysis showed that the adverse impact of hyperuricemia was only pronounced in males (HR: 1.73, 95% CI: 1.18-2.53, p = 0.005) but not in females (HR: 0.98, 95% CI: 0.57-1.66, p = 0.933).

Conclusion

Hyperuricemia is significantly associated with increased risk of MACE in the nonobstructive CAD rather than in the obstructive CAD.

Diagnostic Value of Angiography-Derived IMR for Coronary Microcirculation and Its Prognostic Implication After PCI

Background: Angiography-derived index of microcirculatory resistance (angio-IMR) is an emerging pressure-wire-free index to assess coronary microvascular function, but its diagnostic and prognostic value remains to be elucidated.

Methods and Results: The study population consisted of three independent cohorts. The internal diagnostic cohort enrolled 53 patients with available hyperemic microcirculatory resistance (HMR) calculated from myocardial blood flow and pressure. The external diagnostic cohort included 35 ischemia and no obstructive coronary artery disease (INOCA) patients and 45 controls. The prognostic cohort included 138 coronary artery disease (CAD) patients who received PCI. Angio-IMR was calculated after the estimation of angiography-derived fractional flow reserve (angio-FFR) using the equation of angio-IMR = estimated hyperemic Pa × angio-FFR × [vessel length/(K × V_diastole)]. The primary outcome was a composite of cardiac death or readmission due to heart failure at 28 months after index procedure. Angio-IMR demonstrated a moderate correlation with HMR (R = 0.74, p < 0.001) and its diagnostic accuracy, sensitivity, specificity, and area under the curve to diagnose INOCA were 79.8, 83.1, 78.0, and 0.84, respectively, with a best cut-off of 25.1. Among prognostic cohort, patients with angio-IMR ≥25.1 showed a significantly higher risk of cardiac death or readmission due to heart failure than those with an angio-IMR <25.1 (18.6 vs. 5.4%, adjusted HR 9.66, 95% CI 2.04–45.65, p = 0.004). Angio-IMR ≥25.1 was an independent predictor for cardiac death or readmission due to heart failure (HR 11.15, 95% CI 1.76–70.42, p = 0.010).

Conclusions: Angio-IMR showed a moderate correlation with HMR and high accuracy to predict microcirculatory dysfunction. Angio-IMR measured after PCI predicts the risk of cardiac death or readmission due to heart failure in patients with CAD.

Clinical Trial Registration: Diagnostic and Prognostic Value of Angiography-derived IMR (CHART-MiCro), NCT04825028.

Prognostic impact of coronary microvascular dysfunction in patients with myocardial infarction with non-obstructive coronary arteries

BACKGROUND

Myocardial infarction with non-obstructive coronary arteries (MINOCA) has been and remained a puzzling heterogeneous entity. The index of microcirculatory resistance (IMR) is a quantitative and specific index for the assessment of microvascular function. However, the role of IMR in MINOCA has not yet been studied. This study aimed to evaluate the prognostic value of coronary microvascular function, as assessed by coronary angiography‑derived index of microvascular resistance (caIMR) in MINOCA patients.

METHOD

This study included 109 MINOCA patients. Microvascular function was assessed by caIMR and was analyzed in 280 coronary arteries. The primary endpoint of the study was MACE, defined as cardiovascular death, nonfatal MI, heart failure, stroke and angina rehospitalization. The best cut-off of caIMR was derived from ROC analysis based on MACE prediction.

RESULTS

The patients were classified into high caIMR (caIMR>43U) and low caIMR (caIMR≤43U) based on a caIMR cut-off value of 43U. High caIMR was observed in 55 (50.5%) patients. A total of 27 MACE occurred during the 2 years of follow-up. MACE rate was significantly higher in patients with high caIMR than in patients with low caIMR (36.4% vs 13.0%, P=0.005). The Kaplan-Meier curves showed a significantly increased risk of MACE in patients with high caIMR (log-rank P=0.001). Cox multivariate analysis showed that caIMR>43 was a highly independent predictor of MACE (HR, 3.08; 95% CI, 1.13 - 8.35; P=0.027).

CONCLUSIONS

caIMR is a strong predictor of clinical outcome among MINOCA patients. The evaluation of IMR can provide an objective risk stratification method for patients with MINOCA.

Hyperuricemia Predicts Adverse Outcomes After Myocardial Infarction With Non-obstructive Coronary Arteries

Background: Serum uric acid (SUA) is a well-known predictor of adverse outcomes in patients with various clinical conditions. However, the impact of SUA on patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) remains unclear. Here, we aimed at investigating the potential association between hyperuricemia and the adverse outcomes in MINOCA patients. Methods: Overall, 249 MINOCA patients were enrolled in the present study. Clinical characteristics and laboratory data, were measured in all patients. Based on SUA levels, patients were classified into two groups; the hyperuricemia group [SUA level > 6 mg/dL (360 μmol/L) in women and > 7 mg/dL (420 μmol/L) in men], and the normuricemia group. The primary endpoint of our study was major adverse cardiac events (MACE), defined as cardiovascular death, stroke, heart failure, non-fatal MI, and angina rehospitalization. Results: Seventy-two patients were in hyperuricemia group and 177 in normuricemia group. Fifty-two MACE events were recorded after 30 months of follow-up period. The incidence of MACE was higher in hyperuricemia group compared with normuricemia group (31.9 vs. 16.3%, P = 0.006). Kaplan-Meier survival curves illustrated a significantly increased risk of MACE in hyperuricemia group (log-rank P = 0.006). The multivariable logistic analysis demonstrated that hyperuricemia was independently associated with a high risk of MACE after 30 months of follow-up (OR, 2.234; 95% CI, 1.054-4.737, P = 0.036). Conclusion: Hyperuricemia is associated with adverse outcomes and appears to be an independent predictor of MACE in MINOCA patients. This finding suggests that the SUA levels may serve as a surrogate biomarker related to risk prediction and adverse outcomes of MINOCA patients.

Prognostic Value of Diastolic Dysfunction Derived From D-SPECT in Coronary Artery Disease Patients With Normal Ejection Fraction

Diastolic dysfunction (DD) with normal systolic function has been elucidated to be associated with heart failure and worse prognosis. The recently introduced single photon emission computed tomography (SPECT) with dedicated cardiac cadmium-zinc-telluride (CZT) cameras (D-SPECT) is a novel method to quantitate left ventricular functional parameters. We aimed to evaluate the prognostic value of DD derived from D-SPECT in coronary artery disease (CAD) patients with normal ejection fraction. All CAD patients who underwent D-SPECT and invasive coronary angiography within 3 months were considered. DD was defined as peak filling rate (PFR) <2.1 end diastolic volume (EDV, ml)/s according to the D-SPECT results. Patients were divided into three groups: group 1 (n = 226)-normal PFR; group 2 (n = 67)-ischemia-related DD (abnormal stress PFR and normal rest PFR); and group 3 (n = 106)-rest DD (abnormal rest PFR). The primary clinical endpoint of the present study was a composite of heart failure events (HFE). A total of 399 consecutive CAD patients with normal systolic function undergoing stress D-SPECT were analyzed. The incidence rates of HFE among the three groups were 4.0, 7.5, and 11.3%, respectively. Cox regression analysis showed that the multivariate predictors of HFE were rest PFR, diabetes mellitus, obesity, and old age. DD derived from D-SPECT in CAD patients with normal ejection fraction is predictive of HFE.

Does Sex Influence Outcomes in Myocardial Infarction With Nonobstructive Coronary Arteries?

We examined differences in clinical profiles, predictors, and outcomes among patients with myocardial infarction (MI) with nonobstructive coronary arteries (MINOCAs) by sex. Data of 259 (132 males and 127 females) patients with MINOCA were consecutively collected. The primary clinical end point was major adverse cardiovascular events (MACE), including cardiovascular death, nonfatal MI, stroke, heart failure, and angina rehospitalization. Female patients with MINOCA were likely to be older than male patients with higher non-ST elevation myocardial infarction rate. Total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels were higher in female patients while male patients were more likely to have a smoking history, greater ST elevation myocardial infarction rate, higher diastolic blood pressure, and more alcohol use. During the 2-year follow-up, the incidence of MACE in males and females was similar (18% vs 20.2%, respectively; P = .673). The multivariable predictors of MACE in the female group were age, hypertension, and left ventricular ejection fraction (LVEF), whereas diabetes, smoking, and LVEF were multivariable predictors of MACE in the male group. In conclusion, there were differences in the clinical profiles between sexes. Clinical outcome was similar between male and female patients with MINOCA, whereas predictive risk factors varied.

Prognostic Value of GRACE Risk Scores in Patients With Non-ST-Elevation Myocardial Infarction With Non-obstructive Coronary Arteries

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a special type of myocardial infarction (MI). The GRACE risk score is commonly used to predict major adverse cardiovascular events (MACE) in non-ST-elevation myocardial infarction patients, and the suitability of the GRACE risk score for prognostic stratification in patients with MINOCA remains uncertain. This study aimed to investigate whether the GRACE risk score is capable of predicting MACE in MINOCA patients with NSTE. We calculated the GRACE risk score for 340 consecutive MINOCA patients with NSTE. Patients were divided into a low-intermediate risk group (≤ 140, 48.8%) and a high risk group (>140, 51.2%) according to their GRACE risk scores. The clinical characteristics and outcomes of the patients were assessed. Patients in the high risk group tended to be older and to have more comorbidities. At the 1-year follow-up, the rate of cardiac death in the high risk group was significantly higher than that in the low-intermediate-risk group (p = 0.010). There was no significant difference in non-fatal MI, stroke, heart failure, or cardiovascular-related rehospitalization. The incidence of total MACE was significantly higher in patients with high GRACE risk scores than in patients with low GRACE risk scores (p = 0.006). ROC curve analysis showed that the GRACE risk score has moderate value in predicting MACE in NSTE-MINOCA patients. The area under the ROC curve was 0.710 (95% CI 0.625–0.796, P < 0.001). The GRACE risk score provides potentially valuable prognostic information on clinical outcome when applied to MINOCA patients with NSTE.

A Dynamic Multi-Scale Network for EEG Signal Classification

Accurate and automatic classification of the speech imagery electroencephalography (EEG) signals from a Brain-Computer Interface (BCI) system is highly demanded in clinical diagnosis. The key factor in designing an automatic classification system is to extract essential features from the original input; though many methods have achieved great success in this domain, they may fail to process the multi-scale representations from different receptive fields and thus hinder the model from achieving a higher performance. To address this challenge, in this paper, we propose a novel dynamic multi-scale network to achieve the EEG signal classification. The whole classification network is based on ResNet, and the input signal first encodes the features by the Short-time Fourier Transform (STFT); then, to further improve the multi-scale feature extraction ability, we incorporate a dynamic multi-scale (DMS) layer, which allows the network to learn multi-scale features from different receptive fields at a more granular level. To validate the effectiveness of our designed network, we conduct extensive experiments on public dataset III of BCI competition II, and the experimental results demonstrate that our proposed dynamic multi-scale network could achieve promising classification performance in this task.

A One-Dimensional CNN-LSTM Model for Epileptic Seizure Recognition Using EEG Signal Analysis

Frequent epileptic seizures cause damage to the human brain, resulting in memory impairment, mental decline, and so on. Therefore, it is important to detect epileptic seizures and provide medical treatment in a timely manner. Currently, medical experts recognize epileptic seizure activity through the visual inspection of electroencephalographic (EEG) signal recordings of patients based on their experience, which takes much time and effort. In view of this, this paper proposes a one-dimensional convolutional neural network-long short-term memory (1D CNN-LSTM) model for automatic recognition of epileptic seizures through EEG signal analysis. Firstly, the raw EEG signal data are pre-processed and normalized. Then, a 1D convolutional neural network (CNN) is designed to effectively extract the features of the normalized EEG sequence data. In addition, the extracted features are then processed by the LSTM layers in order to further extract the temporal features. After that, the output features are fed into several fully connected layers for final epileptic seizure recognition. The performance of the proposed 1D CNN-LSTM model is verified on the public UCI epileptic seizure recognition data set. Experiments results show that the proposed method achieves high recognition accuracies of 99.39% and 82.00% on the binary and five-class epileptic seizure recognition tasks, respectively. Comparing results with traditional machine learning methods including k-nearest neighbors, support vector machines, and decision trees, other deep learning methods including standard deep neural network and CNN further verify the superiority of the proposed method.

Low Free Triiodothyronine as a Predictor of Poor Prognosis in Patients With Myocardial Infarction With Non-Obstructive Coronary Arteries

BACKGROUND

Low free triiodothyronine (fT3) level is strongly associated with poor prognosis in various patient populations. However, the role of fT3 in the risk of clinical outcomes in myocardial infarction with non-obstructive coronary arteries (MINOCA) has not been studied. Our study aimed to evaluate the association between low fT3 levels and the clinical outcomes of MINOCA patients.

METHODS

A total of 218 MINOCA patients without a history of thyroid disease were enrolled in the study. Demographic, baseline clinical data, thyroid hormones, and other biochemical parameters were assessed in all patients. According to the fT3 levels, the present study was classified into two groups: the low fT3 group (fT3<3.5 pmol/L) and the normal fT3 group (fT3 3.5-6.5 pmol/L). The endpoint of the study was major adverse cardiac events (MACE).

RESULTS

Fifty-nine patients were in the low fT3 group and 159 patients were in the normal fT3 group. Over the two years of follow-up, 36 MACE have occurred. The occurrence of MACE was higher in the low fT3 group compared with normal fT3 group (25.4% vs 13.2%; P=0.031). Kaplan-Meier survival curves showed a significantly increased risk of MACE in patients with low fT3 (log-rank P=0.027). Multivariable logistic regression analysis stated that high fT3 was independently associated with lower risk of MACE after two years of follow up (OR, 0.623; 95% CI, 0.399- 0.972; P=0.037).

CONCLUSION

Low fT3 levels were significantly associated with increased risk of MACE in patients with MINOCA. This finding suggests that the fT3 levels may serve as a potential biomarker in risk stratification of MINOCA patients.

An Investigation of Deep Learning Models for EEG-Based Emotion Recognition

Emotion is the human brain reacting to objective things. In real life, human emotions are complex and changeable, so research into emotion recognition is of great significance in real life applications. Recently, many deep learning and machine learning methods have been widely applied in emotion recognition based on EEG signals. However, the traditional machine learning method has a major disadvantage in that the feature extraction process is usually cumbersome, which relies heavily on human experts. Then, end-to-end deep learning methods emerged as an effective method to address this disadvantage with the help of raw signal features and time-frequency spectrums. Here, we investigated the application of several deep learning models to the research field of EEG-based emotion recognition, including deep neural networks (DNN), convolutional neural networks (CNN), long short-term memory (LSTM), and a hybrid model of CNN and LSTM (CNN-LSTM). The experiments were carried on the well-known DEAP dataset. Experimental results show that the CNN and CNN-LSTM models had high classification performance in EEG-based emotion recognition, and their accurate extraction rate of RAW data reached 90.12 and 94.17%, respectively. The performance of the DNN model was not as accurate as other models, but the training speed was fast. The LSTM model was not as stable as the CNN and CNN-LSTM models. Moreover, with the same number of parameters, the training speed of the LSTM was much slower and it was difficult to achieve convergence. Additional parameter comparison experiments with other models, including epoch, learning rate, and dropout probability, were also conducted in the paper. Comparison results prove that the DNN model converged to optimal with fewer epochs and a higher learning rate. In contrast, the CNN model needed more epochs to learn. As for dropout probability, reducing the parameters by ~50% each time was appropriate.

MNL-Network: A Multi-Scale Non-local Network for Epilepsy Detection From EEG Signals

Epilepsy is a prevalent neurological disorder that threatens human health in the world. The most commonly used method to detect epilepsy is using the electroencephalogram (EEG). However, epilepsy detection from the EEG is time-consuming and error-prone work because of the varying levels of experience we find in physicians. To tackle this challenge, in this paper, we propose a multi-scale non-local (MNL) network to achieve automatic EEG signal detection. Our MNL-Network is based on 1D convolution neural network involving two specific layers to improve the classification performance. One layer is named the signal pooling layer which incorporates three different sizes of 1D max-pooling layers to learn the multi-scale features from the EEG signal. The other one is called a multi-scale non-local layer, which calculates the correlation of different multi-scale extracted features and outputs the correlative encoded features to further enhance the classification performance. To evaluate the effectiveness of our model, we conduct experiments on the Bonn dataset. The experimental results demonstrate that our MNL-Network could achieve competitive results in the EEG classification task.

Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA): A Review of the Current Position

Myocardial infarction with nonobstructive coronary arteries (MINOCA) remains a puzzling clinical entity that is characterized by clinical evidence of myocardial infarction (MI) with normal or near-normal coronary arteries on angiography (stenosis <50%). Major advances in understanding this condition have been made in recent years. The precise pathogenesis is poorly understood and is being studied and examined further. Guidelines indicate that MINOCA is a group of heterogeneous diseases with different mechanisms of pathology. Since there are multiple possible pathological mechanisms, it is not certain that the classical secondary prevention and treatment strategy for MI with obstructive coronary artery disease (MI-CAD) is optimal for MINOCA patients. The prognosis and predictors for MINOCA patients remain unclear. Although the prognosis is slightly better for MINOCA patients than for MI-CAD patients, MINOCA isn't always benign. The aim of this paper was to review the literature and evaluate MINOCA epidemiology, clinical features, etiology, diagnosis, treatment, and prognosis.

Clinical Outcomes and Predictors of ST-Elevation Versus Non-ST-Elevation Myocardial Infarction with Non-Obstructive Coronary Arteries

BACKGROUND

Myocardial infarction with nonobstructive coronary arteries (MINOCA) can be clinically categorized as ST-segment elevation (STE) and non-ST-segment elevation (NSTE), whose clinical prognosis are poorly understood. The aim of this study was to compare the clinical outcome and their predictors of patients with STE and NSTE in MINOCA population.

METHODS

A total of 265 patients with MINOCA (102 with STE, and 163 with NSTE) were consecutively collected. Clinical profile, prognosis, and predictors of all patients were assessed.

RESULTS

The proportion of patients with NSTE was greater than patients with STE in MINOCA population. Patients with NSTE were older and more likely to be female and had a higher incidence of atrial fibrillation. Both high density lipoprotein (HDL) and N-terminal pro-brain natriuretic peptide (NT-proBNP) were higher in the NSTE group. Patients with STE were more likely to have a history of smoking and a higher diastolic blood pressure. During the 1-year follow up, there were no differences in the outcomes between the STE and NSTE groups, with no significant differences in mortality and a similar rate of major adverse cardiovascular events (MACE) (20.9% vs 19.3%, P = 0.767). The multivariable predictors of MACE in the NSTE groups were age, lower level of total cholesterol, hypertension, and smoking history, whereas reduced left ventricular ejection fraction, and diabetes mellitus were the multivariable predictors of major adverse cardiac events in the STE group.

CONCLUSIONS

There were differences in the clinical profile between STE and NSTE in the MINOCA population, whereas the outcomes during the 1-year follow up were similar. The STE and NSTE groups had different predictive factors for major adverse cardiac events.

Patient-Specific Coronary Artery 3D Printing Based on Intravascular Optical Coherence Tomography and Coronary Angiography

Despite the new ideas were inspired in medical treatment by the rapid advancement of three-dimensional (3D) printing technology, there is still rare research work reported on 3D printing of coronary arteries being documented in the literature. In this work, the application value of 3D printing technology in the treatment of cardiovascular diseases has been explored via comparison study between the 3D printed vascular solid model and the computer aided design (CAD) model. In this paper, a new framework is proposed to achieve a 3D printing vascular model with high simulation. The patient-specific 3D reconstruction of the coronary arteries is performed by the detailed morphological information abstracted from the contour of the vessel lumen. In the process of reconstruction which has 5 steps, the morphological details of the contour view of the vessel lumen are merged along with the curvature and length information provided by the coronary angiography. After comparing with the diameter of the narrow section and the diameter of the normal section in CAD models and 3D printing model, it can be concluded that there is a high correlation between the diameter of vascular stenosis measured in 3D printing models and computer aided design models. The 3D printing model has high-modeling ability and high precision, which can represent the original coronary artery appearance accurately. It can be adapted for prevascularization planning to support doctors in determining the surgical procedures.

The Integrative Regulatory Network of circRNA, microRNA, and mRNA in Atrial Fibrillation

Atrial fibrillation (AF) is the most common irregular heart rhythm which influence approximately 1–2% of the general population. As a potential factor for ischemic stroke, AF could also cause heart failure. The mechanisms behind AF pathogenesis is complex and remains elusive. As a new category of non-coding RNAs (ncRNAs), circular RNAs (circRNAs) have been known as the key of developmental processes, regulation of cell function, pathogenesis of heart diseases and pathological responses which could provide novel sight into the pathogenesis of AF. circRNAs function as modulators of microRNAs in cardiac disease. To investigate the regulatory mechanism of circRNA in AF, especially the complex interactions among circRNA, microRNA and mRNA, we collected the heart tissues from three AF patients and three healthy controls and profiled their circRNA expressions with circRNA Microarray. The differentially expressed circRNAs were identified and the biological functions of their interaction microRNAs and mRNAs were analyzed. Our results provided novel insights of the circRNA roles in AF and proposed highly possible interaction mechanisms among circRNAs, microRNAs, and mRNAs.

The MEDEA FAR-EAST Study: Conceptual framework, methods and first findings of a multicenter cross-sectional observational study

BACKGROUND

The substantial increase in cardiovascular diseases (CVD) in China over the last three decades warrants comprehensive preventive primary and secondary strategies. Prolonged prehospital delay (PHD) has been identified as a substantial barrier to timely therapeutic interventions for acute myocardial infarction (AMI). Despite worldwide efforts to decrease the patient's decision-making time, minimal change has been achieved so far. Here, we aim to describe the conceptual framework and methods and outline key data of the MEDEA FAR-EAST Study, which aimed to elucidate in-depth barriers contributing to delay in Chinese AMI-patients.

METHODS

Data sources of this multicenter cross-sectional observational study are a standardized bedside interview, a self-administered tailored questionnaire tool and the patient chart. PHD was defined as the main outcome and triangulated at bedside. Standard operation procedures ensured uniform data collection by trained study personnel. The study was ethically approved by Tongji-Hospital and applied to all participating hospitals.

RESULTS

Among 379 consecutively screened patients, 296 (78.1%) fulfilled eligibility criteria. A total of 241 (81.4%) AMI-patients were male and 55 (18.6%) female. Mean age was 62.9 years. Prehospital delay time was assessed for 294 (99.3%) patients. Overall median PHD was 151 min with no significant sex difference. Symptom mismatch was present in 200 (69.7%) patients and 106 (39.0%) patients did not attribute their symptoms to cardiac origin. A total of 33 (12.4%) patients suffered from depression, 31 (11.7%) from anxiety and 141 (53.2%) patients employed denial as their major coping style.

CONCLUSION

This is the first study on prehospital delay with emphasis on psychological variables in Chinese AMI-patients. A comprehensive assessment tool to measure clinical and psychological factors was successfully implemented. Socio-demographic key data proved a good fit into preexisting Chinese literature. Potential barriers including cardiac denial and symptom-mismatch were assessed for the first time in Chinese AMI-patients. The pretested selection of instruments allows future in depth investigations into barriers to delay of Chinese AMI-patients and enables inter-cultural comparisons.

A New Pulse Coupled Neural Network (PCNN) for Brain Medical Image Fusion Empowered by Shuffled Frog Leaping Algorithm

Recent research has reported the application of image fusion technologies in medical images in a wide range of aspects, such as in the diagnosis of brain diseases, the detection of glioma and the diagnosis of Alzheimer's disease. In our study, a new fusion method based on the combination of the shuffled frog leaping algorithm (SFLA) and the pulse coupled neural network (PCNN) is proposed for the fusion of SPECT and CT images to improve the quality of fused brain images. First, the intensity-hue-saturation (IHS) of a SPECT and CT image are decomposed using a non-subsampled contourlet transform (NSCT) independently, where both low-frequency and high-frequency images, using NSCT, are obtained. We then used the combined SFLA and PCNN to fuse the high-frequency sub-band images and low-frequency images. The SFLA is considered to optimize the PCNN network parameters. Finally, the fused image was produced from the reversed NSCT and reversed IHS transforms. We evaluated our algorithms against standard deviation (SD), mean gradient (Ḡ), spatial frequency (SF) and information entropy (E) using three different sets of brain images. The experimental results demonstrated the superior performance of the proposed fusion method to enhance both precision and spatial resolution significantly.

Myocardial infarction with non-obstructive coronary arteries (MINOCA) in Chinese patients: Clinical features, treatment and 1 year follow-up

BACKGROUND

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is characterised by clinical evidence of myocardial infarction with normal or near-normal coronary arteries on angiography (stenosis<50%). We investigated clinical features among Chinese MINOCA patients and one-year follow-up on medication management and cardiovascular events.

METHODS

The data of 2029 patients with acute myocardial infarction were consecutively collected. MINOCA patients were identified with coronary angiography (<50% stenosis). Clinical features, medication management and cardiovascular events were assessed.

RESULTS

One hundred and twenty-eight patients (6.3%) were diagnosed as MINOCA. Compared with the myocardial infarction with obstructive coronary arteries (MI-CAD) patients, the prevalence of traditional risk factors of CAD was lower in MINOCA patients. The levels of TG, LDL-C, cTnT, CK-MB and myoglobin in the MINOCA group were significantly lower, whereas LVEF was higher. MINOCA patients are less likely to receive secondary prevention medication for MI, and use of all recommended drugs decreased at one-year follow-up. MACE in the MINOCA group was lower. After adjusting related risk factors, logistic analysis showed MINOCA was independently associated with lower risk of MACE. Independent predictors for MACE in MINOCA patients were older age (≥60 years), females, atrial fibrillation and reduced LVEF.

CONCLUSION

Compared with MI-CAD, MINOCA was accompanied by fewer traditional risk factors of CAD, less likely to be discharged upon secondary prevention medication of MI and the occurrence of MACE during 1 year follow-up was lower. Older age (≥60 years), females, atrial fibrillation and reduced LVEF were independent risk factors for MACE in MINOCA patients within one year.

Management of Hypertension Using Olmesartan Alone or in Combination

Hypertension is one of the most significant and consistent risk factors for many cardiovascular diseases. The global prevalence of hypertension has dramatically increased over recent years. Life-style and genetic factors are generally considered to be primarily responsible for the incidence of hypertension. Concerning the high morbidity rate, setting up an updated standard for hypertensive patients becomes indispensable. According to the widely accepted standard treatments for hypertension, these four basic principles should be taken into account: low dosage; medication should provide long term-control; combination therapies are becoming common; personalized treatments are a newer approach. In most patients with hypertension, adequate control of BP can be achieved with combined therapy. Therefore, antihypertensive agents with complementary mechanisms are now recommended. In this review, we focus on the pharmacology, antihypertensive efficacy, and adverse events (AEs) of olmesartan medoxomil, either alone or in combination with other antihypertensive medications. In conclusion, olmesartan medoxomil, is an angiotensin II receptor blocker with an excellent efficacy in the reduction and stabilization of blood pressure. When combined with calcium channel blockers (CCBs) and diuretics, olmesartan medoxomil has a better effect on controlling BP and reducing AEs in patients.

The role of mAKAPβ in the process of cardiomyocyte hypertrophy induced by angiotensin II

Angiotensin II (AngII) is the central product of the renin-angiotensin system (RAS) and this octapeptide contributes to the pathophysiology of cardiac hypertrophy and remodeling. mAKAPβ is an A-kinase anchoring protein (AKAP) that has the function of binding to the regulatory subunit of protein kinase A (PKA) and confining the holoenzyme to discrete locations within the cell. In this study, we aimed to investigate the role of mAKAPβ in AngII‑induced cardiomyocyte hypertrophy and the possible mechanisms involved. Cultured cardiomyocytes from neonatal rats were treated with AngII. Subsequently, the morphology of the cardiomyocytes was observed and the expression of mAKAPβ and cardiomyocyte hypertrophic markers was measured. mAKAPβ‑shRNA was constructed for RNA interference; the expression of mAKAPβ and hypertrophic markers, the cell surface area and the [3H]Leucine incorporation rate in the AngII‑treated rat cardiomyocytes were detected following RNA interference. Simultaneously, changes in the expression levels of phosphorylated extracellular signal-regulated kinase (p-ERK)2 in the cardiomyocytes were assessed. The cell size of the AngII-treated cardiaomyocytes was significantly larger than that of the untreated cardiomyocytes. The expression of hypertrophic markers and p-ERK2, the cell surface area and the [3H]Leucine incorporation rate were all significantly increased in the AngII‑treated cells. However, the expression of mAKAPβ remained unaltered in this process. RNA interference simultaneously inhibited the protein expression of mAKAPβ and p‑ERK2, and the hypertrophy of the cardiomyocytes induced by AngII was attenuated. These results demonstrate that AngII induces hypertrophy in cardiomyocytes, and mAKAPβ is possibly involved in this process. The effects of mAKAPβ on AngII‑induced cardiomyocyte hypertrophy may be associated with p-ERK2 expression.

RANKL inhibits cell proliferation by regulating MALAT1 expression in a human osteoblastic cell line hFOB 1.19

Receptor activator of NF&mdash;&#954;B ligand (RANKL), a TNF&mdash;related protein, is a key factor regulating bone metabolism. It has been well known that RANKL&mdash;mediated signaling regulates the formation, activation and survival of osteoclast in normal bone modeling and remodeling, and also plays an important role in a variety of pathologic conditions. However, there is no direct evidence about the effect of RANKL on osteoblast. Herein, we investigated whether RANKL had effect on cell proliferation in a normal human fetal osteoblastic cell line hFOB 1.19. MTT assay showed that RANKL inhibited hFOB 1.19 cells growth in a dose&mdash;dependent and time&mdash;dependent manner. Importantly, we found that RANKL induced the expression of a lncRNA, MALAT1, for the first time. Knockdown of RANK by siRNA blocked the induction of MALAT1 by RANKL. By infection with MALAT1 siRNA, MALAT1 knockdown reversed RANKL&mdash;induced cells growth inhibition and cell cycle arrest. In addition, MALAT1 also regulated OPG expression in hFOB 1.19 cells. In conclusion, RANKL, binding to its receptor RANK, inhibited cell proliferation via MALAT1 upregulation in osteoblast cells in vitro.

Comparative analyses of histone H3K9 trimethylations in the heart and spleen of normal humans

The global features of trimethylations of histone 3 at lysine 9 (H3K9me3) have been well studied in recent years; however, most of these studies were performed in mammalian cell lines. In this study, we generated genome-wide maps of H3K9me3 of the human heart and spleen using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) technology. We examined the global patterns of H3K9me3 in both tissues and found that modifications were closely associated with tissue-specific expression, function, and development. In addition, we found that 169 genes displayed significant H3K9me3 differences between the heart and spleen. Among these genes, 64 were heart-H3K9me3-specific, 87 genes were spleen-H3K9me3-specific, and 18 were shared in both heart- and spleen-H3K9me3. In conclusion, we observed significant differences in H3K9me3 in the heart and spleen, which may help to explain epigenetic differences between these tissues. Such novel findings highlight the significance of H3K9me3 as a potential biomarker or promising target for epigenetic-based disease treatment.

SIRT5: a safeguard against oxidative stress-induced apoptosis in cardiomyocytes

BACKGROUND

SIRT5 is located in the mitochondria, and plays a crucial role in the regulation of metabolic process and cellular apoptosis. Cardiomyocytes are abundant in mitochondria. However, the role of SIRT5 in oxidative stress-induced apoptosis is still unknown in cardiomyocytes.

METHODS AND RESULTS

Western blots analysis revealed that SIRT5 is significantly down-regulated in cardiomyocytes upon oxidative stress. MTT assay, DAPI staining, and caspase 3/7 activity assay were used to estimate apoptosis development. The result suggested that compared with the wild-type group, SIRT5 knockdown results in a marked reduction in cell viability, and a significant increase in the number of apoptotic cells and the caspase 3/7 activity. Protein immunoprecipitation revealed a direct interaction between Bcl-Xl and SIRT5. Apoptosis assay and western blot anaylsis suggested that SIRT5 levels could affect the levels of Bcl-Xl expression, but have no effect on the apoptosis development in Bcl-Xl knockdown cells.

CONCLUSION

This study reveals a novel role of SIRT5 in the regulation of oxidative stress-induced apoptosis in cardiomyocytes. Pharmacological interventions on SIRT5 expression may be useful in the treatment of oxidative stress-related cardiac injury.