Evaluation of left ventricular diastolic function in patients with coronary microvascular dysfunction via cardiovascular magnetic resonance feature tracking.

Background: Coronary microvascular dysfunction (CMD) has been suggested to be one of the pathologic mechanisms contributing to heart failure with preserved left ventricular ejection fraction (LVEF) and left ventricular (LV) diastolic dysfunction. We therefore aimed to evaluate LV diastolic function in patients with CMD using cardiovascular magnetic resonance feature tracking (CMR-FT). Methods: We prospectively enrolled 115 patients referred to cardiology clinics for chest pain assessment who subsequently underwent coronary computed tomography angiogram and stress perfusion CMR. CMD was defined as the presence of subendocardial inducible ischemia detected through visual assessment. LV diastolic function was evaluated using CMR-derived volume-time curves and CMR-FT parameters. The former included early peak filling rate (PFR) and time to PFR; the latter included LV global/regional peak longitudinal diastolic strain rate (LDSR), circumferential diastolic strain rate (CDSR), and radial diastolic strain rate (RDSR). Results: A total of 92 patients with 1,312 segments were eventually included. Of these, 19 patients were classified as non-CMD (48.8±11.2 years; 63.2% male) and 73 as with CMD (52.3±11.9 years; 54.8% male). The LVEFs were similar and preserved in both groups (P=0.266). At the per-patient level, no differences were observed in PFR, time to PFR, or LV global diastolic strain rates between the two groups. At the per-segment level, 51% (665/1,312) of the myocardial segments were classified as CMD, whereas 49% (647/1,312) were classified as non-CMD. CMD segments showed significantly lower regional CDSR (P=0.019) and RDSR (P=0.006) compared with non-CMD segments. Conclusions: Despite normal LV ejection fraction in CMD patients, decreased LV diastolic function in CMD myocardial segments indicates early diastolic impairment.

HbA1c is related to microcirculation blood perfusion in patients with coronary microvascular disease using stress perfusion cardiac magnetic resonance: An observational study.

BACKGROUND: In coronary microvascular disease (CMD) patients, the incidence of major adverse cardiovascular events (MACEs) in patients with myocardial perfusion reserve index (MPRI) ≤ 1.47 is three times higher than that in MPRI > 1.47. We investigated whether the increase of glycated hemoglobin A1c (HbA1c) could increase the risk of MPRI ≤1.47 in diabetic and non-diabetic patients. METHODS: From November 2019, patients with ischemic symptoms but without obstructive coronary disease were screened. Use MPRI measured by stress perfusion cardiac magnetic resonance (CMR) to reflect microcirculation blood perfusion, and MPRI <2.5 were included. The patients were divided into two groups based on MPRI was greater or <1.47. The risk factors for CMD were explored using logistic regression analysis. RESULTS: A total of 80 patients with an MPRI of 1.69 ± 0.79 were included. CMD patients with an MPRI of ≤1.47(n = 33) were higher than MPRI of >1.47(n = 47) in age, presence of diabetes mellitus, fasting blood glucose levels and HbA1c levels (P < 0.05). In non-diabetic patients, increased HbA1c was associated with the risk of MPRI≤1.47 (OR = 0.017, 95%CI: 0.050-1.107, P = 0.045). Compared with non-diabetic patients with HbA1c < 6.0, non-diabetic patients with HbA1c ≥ 6.0 increased the risk of MPRI of ≤1.47 (OR = 0.219, 95%CI: 0.069-0.697, P = 0.010). In diabetic patients, HbA1c was not associated with the risk of MPRI of ≤1.47 (OR = 1.043, 95%CI: 0.269, 4.044, P = 0.952). And compared with non-diabetic patients with HbA1c <6.0, diabetic patients with HbA1c <6.0 (OR = 0.917, 95%CI: 0.233-3.610, P = 0.901) or ≥6.0 (OR = 0.326, 95%CI: 0.073-1.446, P = 0.140), the risk of MPRI ≤ 1.47 was not further increased. CONCLUSIONS: In non-diabetic patients, elevated HbA1c is related to MPRI≤1.47(a value increased incidence of MACEs). Therefore, in patients with undiagnosed diabetes, early management of glycosylated hemoglobin is very important. TRIAL REGISTRATION: This clinical trial has been registered in the Chinese clinical Trial Registry with an identifier: ChiCTR1900025810.

Exosomes as a Cell-free Therapy for Myocardial Injury Following Acute Myocardial Infarction or Ischemic Reperfusion.

Exosomes, which contain miRNA, have been receiving growing attention in cardiovascular therapy because of their role in mediating cell-cell communication, autophagy, apoptosis, inflammation, and angiogenesis. Several studies have suggested that miRNA derived from exosomes can be used to detect myocardial infarctions (MI) in patients. Basic research also suggests that exosomes could serve as a potential therapeutic target for treating acute myocardial infarction. Ischemia/reperfusion (IR) injury is associated with adverse cardiac events after acute MI. We aim to review the potential benefits and mechanisms of exosomes in treating MI and IR injury.

Efficacy of Colchicine in the Treatment of Patients With Coronary Artery Disease: A Mini-Review.

PURPOSE: This review of colchicine, an effective anti-inflammatory agent, examines whether the reduction in ischemic events produced by colchicine translates to a reduction in mortality, the optimal duration of treatment, and the patient populations that benefits the most from colchicine treatment. METHODS: We performed a comprehensive PubMed database search using the key words colchicine and coronary heart disease on August 23, 2021. We also screened the included reference list of manuscripts. FINDINGS: Colchicine's role in the secondary prevention of coronary artery disease has been the focus of recent large-scale randomized controlled trials in chronic coronary syndrome (ie, the Low-Dose Colchicine and Low-Dose Colchicine 2 trials), acute myocardial infarction (the Colchicine Cardiovascular Outcomes Trial and Colchicine in Patients With Acute Coronary Syndrome trial), and after percutaneous coronary intervention (the Colchicine-Percutaneous Coronary Intervention trial). IMPLICATIONS: Current evidence suggests that low-dose colchicine (0.5 mg once a day) reduces the risk of cardiovascular events among patients with acute myocardial infarction or chronic coronary syndrome. Colchicine has the potential to become a new standard therapy for the prevention of coronary artery disease-related atherothrombotic events because it is effective and cost-efficient and has a well-tolerated safety profile.

Pathophysiology and molecular mechanism of caveolin involved in myocardial protection strategies in ischemic conditioning.

Multiple pathophysiological pathways are activated during the process of myocardial injury. Various cardioprotective strategies protect the myocardium from ischemia, infarction, and ischemia/reperfusion (I/R) injury through different targets, yet the clinical translation remains limited. Caveolae and its structure protein, caveolins, have been suggested as a bridge to transmit damage-preventing signals and mediate the protection of ultrastructure in cardiomyocytes under pathological conditions. In this review, we first briefly introduce caveolae and caveolins. Then we review the cardioprotective strategies mediated by caveolins through various pathophysiological pathways. Finally, some possible research directions are proposed to provide future experiments and clinical translation perspectives targeting caveolin based on the investigative evidence.

Efficacy and safety of drug-coated balloons in the treatment of de novo coronary lesions in very small vessels: a prospective, multicenter, single-arm trial.

Background: Evidence of the use of drug-coated balloons (DCB) in de novo large or small coronary lesions and in-stent restenosis has accumulated over the past years. Due to their anatomical peculiarity, the treatment of very small vessels (VSV) (lumen diameter <2 mm) is still a controversial issue. Studies that examine the use of DCB in VSV are limited. We investigated the efficacy and safety of using DCBs for the de novo coronary lesions in VSV undergoing percutaneous coronary intervention (PCI). Methods: In this prospective, single-arm study, we enrolled adult patients with coronary artery disease from six centers in China. A total of 29 patients had VSV with a target lesion stenosis ≥70% were included. All patients were treated with DCB. The primary endpoint was late lumen loss (LLL) at 9 months of follow-up. The secondary endpoints were major adverse cardiac events including target lesion revascularization, death, or myocardial infarction at 9 months of follow-up. Results: Twenty-nine eligible patients with VSV were enrolled between November 2019 to May 2020. Angiographic and clinical follow-up were completed at 9 months in 18 (56.25%) patients (7 patients refused to final angiography; 2 failed to finish DCB angioplasty; 1 patient request; 1 other causes of death). The mean diameter of the reference vessel of the target lesion was 1.71±0.27 mm, the minimum lumen diameter (MLD) of the target lesion before operation was 0.31±0.24 mm, the average LLL of the target lesion was 0.13±0.28 mm, and the MLD of the target vessel immediately after operation was (1.19±0.20 mm) and at the 9-month follow-up (1.06±0.31 mm) were significantly higher than those before operation (P=0.043). One patient (5.56%) underwent revascularization. No myocardial infarction or death occurred during follow-up after treatment with DCBs. Conclusions: DCB can be a safe and effective alternative in the treatment of de novo coronary lesions in VSV.

Revascularization or medical therapy for stable coronary artery disease patients with different degrees of ischemia: a systematic review and meta-analysis of the role of myocardial perfusion.

OBJECTIVE: This study explored the best treatment strategies for stable coronary artery disease (SCAD) patients with differing levels of ischemic severity. METHODS: We conducted a comprehensive search of the PubMed, EMBASE, and Cochrane databases - searching for relevant articles through 4 February 2021. We selected studies comparing different treatments for patients with SCAD who had received ischemia assessments. The primary outcome was death. The secondary outcomes were major adverse cardiovascular events (MACEs) and myocardial infarction (MI). RESULTS: A total of 11 studies, including 35,607 subjects, were selected for this meta-analysis. Results showed that, compared with medical therapy, revascularization could reduce MACE incidence (odds ratio (OR) 0.73, 95% confidence interval (CI): 0.57-0.94, p < 0.05) in SCAD patients with myocardial ischemia, but that it was not effective for patients without ischemia. For mild ischemia, the incidence of death (OR 0.78, 95% CI: 0.59-1.01, p = 0.063), MACE (OR 0.91, 95% CI: 0.48-1.70, p = 0.762), or MI (OR 1.44, 95% CI: 0.94-2.19, p = 0.093) was the same whether they were treated with revascularization or medical therapy. For moderate to severe ischemia, revascularization reduced the incidence of MACE (OR 0.59, 95% CI: 0.42-0.83, p < 0.05) and MI (OR 0.83, 95% CI: 0.71-0.98, p < 0.05), but the incidence of death (OR 0.73, 95% CI: 0.47-1.12, p = .145) was similar. For SCAD patients with severe ischemia, revascularization may confer survival benefits (OR 0.46, 95% CI: 0.21-1.00, p = 0.05). CONCLUSION: For SCAD patients with moderate to severe ischemia, revascularization reduces the MACE and MI incidences, but does not change the incidence of death. Evaluation for myocardial ischemia is vital when selecting a therapeutic strategy.

Optimal treatment strategies for coronary artery disease in patients with advanced kidney disease: a meta-analysis.

BACKGROUND: Coronary artery disease (CAD) is the leading cause of death in advanced kidney disease. However, its best treatment has not been determined. METHODS: We searched PubMed and Cochrane databases and scanned references to related articles. Studies comparing the different treatments for patients with CAD and advanced CKD (estimated glomerular filtration rate <30 ml/min/1.73 m2 or dialysis) were selected. The primary result was all-cause death, classified according to the follow-up time: short-term (<1 month), medium-term (1 month-1 year), and long-term (>1 year). RESULTS: A total of 32 studies were selected to enroll 84,498 patients with advanced kidney disease. Compared with medical therapy (MT) alone, percutaneous coronary intervention (PCI) was associated with low risk of short-, medium-term and long-term all-cause death (more than 3 years). For AMI patients, compared with MT, PCI was not associated with low risk of short- and medium-term all-cause death. For non-AMI patients, compared with MT, PCI was associated with low risk of long-term mortality (more than 3 years). Compared with MT, coronary artery bypass surgery (CABG) had no significant advantages in each follow-up period of all-cause death. Compared with PCI, CABG was associated with a high risk of short-term death, but low risk of long-term death: 1-3 years; more than 3 years. CABG could also reduce the risk of long-term risk of cardiac death, major adverse cardiovascular events (MACEs), myocardial infarction (MI), and repeat revascularization. CONCLUSIONS: In patients with advanced kidney disease and CAD, PCI reduced the risk of short-, medium- and long- term (more than 3 years) all-cause death compared with MT. Compared with PCI, CABG was associated with a high risk of short-term death and a low risk of long-term death and adverse events.

Effects of Oral Drugs on Coronary Microvascular Function in Patients Without Significant Stenosis of Epicardial Coronary Arteries: A Systematic Review and Meta-Analysis of Coronary Flow Reserve.

Objective: This study aims to investigate the impact of cardiovascular medications on the coronary flow reserve (CFR) in patients without obstructive coronary artery disease (CAD). Methods: We searched PubMed, EMBASE, and Cochrane databases from inception to 15 November 2019. Studies were included if they reported CFR from baseline to follow-up after oral drug therapy of patients without obstructive CAD. Data was pooled using random-effects modeling. The primary outcome was change in CFR from baseline to follow-up after oral drug therapy. Results: A total of 46 studies including 845 subjects were included in this study. Relative to baseline, the CFR was improved by angiotensin-converting enzymes (ACEIs), aldosterone receptor antagonists (ARBs) [standard mean difference (SMD): 1.12; 95% CI: 0.77-1.47], and statins treatments (SMD: 0.61; 95%CI: 0.36-0.85). Six to 12 months of calcium channel blocker (CCB) treatments improved CFR (SMD: 1.04; 95% CI: 0.51-1.58). Beta-blocker (SMD: 0.24; 95% CI: -0.39-0.88) and ranolazine treatment (SMD: 0.31; 95% CI: -0.39-1.01) were not associated with improved CFR. Conclusions: Therapy with ACEIs, ARBs, and statins was associated with improved CFR in patients with confirmed or suspicious CMD. CCBs also improved CFR among patients followed for 6-12 months. Beta-blocker and ranolazine had no impact on CFR.

The effect of Shexiang Tongxin Dropping Pills on coronary microvascular dysfunction (CMVD) among those with a mental disorder and non-obstructive coronary artery disease based on stress cardiac magnetic resonance images: A study protocol.

INTRODUCTION: Coronary microvascular dysfunction (CMVD), highly prevalent among patients with a mental disorder (anxiety or depression), is closely related to adverse cardiac events, including hospitalization, sudden cardiac death, and myocardial infarction. Shexiang Tongxin Dropping Pills (STDP), a traditional Chinese medicine, exerts endothelial protective function by anti-inflammation, anti-oxidative stress, and promoting blood circulation. STDP protects against CMVD in previous fundamental studies. The present trial is aiming at evaluating the effect of STDP on CMVD among depressed or anxious patients with non-obstructive coronary artery disease (NOCAD). METHODS AND ANALYSIS: Seventy-two depressed or anxious patients diagnosed with NOCAD combined with CMVD utilizing coronary artery angiography and stress cardiac magnetic resonance (CMR) will be recruited in the present study. These patients will be randomized into two groups, namely, Nicorandil group (Nicorandil combined with routine medicine), and STDP groups (STDP combined with routine medicine). The change of CMVD status by assessing absolute myocardial blood flow and myocardial reperfusion using stress CMR 3-month after discharge is defined as the primary endpoint. Major adverse cardiac events (MACEs), quality of life (QOL), and metal disorder improvement are defined as the secondary endpoints. Seattle angina questionnaire (SAQ) which is used to assess angina pectoris and QOL will be recorded at 1-, 3-, 6-, 9-, 12-month of follow-up. Seven-item Generalized Anxiety Disorder Scale (GAD-7) and 9-item depression module from the Patient Health Questionnaire (PHQ9) which utilized to evaluate anxiety and depression, respectively, will be recorded at 1-, 3-, 6-, 9-, 12-month of follow-up. This study will first evaluate the efficacy of STDP on CMVD among patients with a mental disorder and NOCAD, and discuss the potential mechanisms, providing therapeutic evidence for the STDP for these patients.