Cardioprotective Effects of Nicorandil on Coronary Heart Disease Patients Undergoing Elective Percutaneous Coronary Intervention

Therapeutic potential of nicorandil beyond anti-anginal drug: A review on current and future perspectives

Nicorandil (NIC) is a well-known anti-anginal agent, which has been recommended as one of the second-line treatments for chronic stable angina as justified by the European guidelines. It shows an efficacy equivalent to that of classic anti-anginal agents. NIC has also been used clinically in various cardiovascular diseases such as variant or unstable angina and reperfusion-induced damage following coronary angioplasty or thrombolysis. Different mechanisms have been involved in the protective effects of nicorandil in various diseases, including opening of adenosine triphosphate-sensitive potassium (KATP) channel and donation of nitric oxide (NO). In recent years, NIC has been found to show numerous pharmacological activities such as neuroprotective, nephroprotective, hepatoprotective, cardioprotective, and testicular protective effects, among other beneficial effects on the body. The present review dwells on the pharmacological potentials of NIC beyond its anti-anginal action.

Cardioprotective and Antianginal Efficacy of Nicorandil: A Comprehensive Review

ABSTRACT

Angina pectoris remains a significant burden despite advances in medical therapy and coronary revascularization. Many patients (up to 30%) with angina have normal coronary arteries, with coronary microvascular disease and/or coronary artery vasospasm being major drivers of the myocardial demand-supply mismatch. Even among patients revascularized for symptomatic epicardial coronary stenosis, recurrent angina remains highly prevalent. Medical therapy for angina currently centers around 2 disparate goals, viz secondary prevention of hard clinical outcomes and symptom control. Vasodilators, such as nitrates, have been first-line antianginal agents for decades, along with beta-blockers and calcium channel blockers. However, efficacy in symptoms control is heterogenous, depending on underlying mechanism(s) of angina in an individual patient, often necessitating multiple agents. Nicorandil (NCO) is an antianginal agent first discovered in the late 1970s with a uniquely dual mechanism of action. Like a typical nitrate, it mediates medium-large vessel vasodilation through nitric oxide. In addition, NCO has adenosine triphosphate (ATP)-dependent potassium channel agonist activity (K ATP ), mediating microvascular dilatation. Hence, it has proven effective in both coronary artery vasospasm and coronary microvascular disease, typically challenging patient populations. Moreover, emerging evidence suggests that cardiomyocyte protection against ischemia through ischemic preconditioning may be mediated through K ATP agonism. Finally, there is now fairly firm evidence in favor of NCO in terms of hard event reduction among patients with stable coronary artery disease, following myocardial infarction, and perhaps even among patients with congestive heart failure. This review aims to summarize the mechanism of action of NCO, its efficacy as an antianginal, and current evidence behind its impact on hard outcomes. Finally, we review other cardiac and emerging noncardiac indications for NCO use.

Myocardial Perfusion in ST-Segment Elevation Myocardial Infarction Patients After Percutaneous Coronary Intervention: Influencing Factors and Intervention Strategies

Aim We aim to explore the factors influencing myocardial perfusion in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PPCI) and evaluate the effects of different intervention strategies on myocardial perfusion improvement. Methods A retrospective analysis was conducted on 300 patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) at our hospital between January 2020 and December 2022. Based on post-procedural coronary angiography results using the thrombolysis in myocardial infarction (TIMI) blood flow grade and myocardial blush grade (MBG), patients were categorized into two groups: the normal perfusion group (TIMI grade 3 or MBG 2-3, n=180) and the impaired perfusion group (TIMI grades 0-2 or MBG 0-1, n=120). The impaired perfusion group was further divided using a random number table into the thrombus aspiration-only group (control group, n=60) and the thrombus aspiration combined with nicorandil group (nicorandil group, n=60). A 1:1 propensity score matching method was employed to adjust for baseline characteristics between the groups. Clinical characteristics, hematological parameters, coronary lesion features, and percutaneous coronary intervention (PCI) technical parameters were compared between the matched groups. Additionally, a multivariate logistic regression analysis was performed to identify independent risk factors influencing myocardial perfusion. Furthermore, the post-procedural myocardial perfusion, cardiac function, and clinical prognosis were compared between the control and nicorandil groups. Results After matching, the baseline characteristics of the two groups were compared. The impaired perfusion group had older age, higher proportion of male patients, higher rates of diabetes and hypertension, longer time from symptom onset to balloon dilation, higher peak cardiac troponin I (cTnI) levels, higher proportion of left main or multivessel involvement, heavier coronary lesion burden, and lower balloon inflation pressure (P<0.05). Multivariate logistic regression analysis revealed that age of ≥65 years (odds ratio {OR}=2.34, 95% confidence interval {CI}=1.23-4.46, P<0.01), time from symptom onset to balloon dilation of ≥6 hours (OR=3.12, 95% CI=1.67-5.83, P<0.01), peak cTnI level of ≥100 ng/mL (OR=4.27, 95% CI=2.18-8.36, P<0.01), left main or multivessel involvement (OR=2.86, 95% CI=1.51-5.41, P<0.01), and balloon inflation pressure of <8 atm (OR=3.45, 95% CI=1.79-6.65, P<0.01) were independent risk factors affecting myocardial perfusion. In the intervention analysis, the nicorandil group showed superior post-procedural TIMI blood flow grade, MBG, left ventricular ejection fraction (LVEF), and New York Heart Association (NYHA) functional classification compared to the control group (P<0.05). During a six-month follow-up, the nicorandil group had a lower incidence of major adverse cardiovascular events (MACE) compared to the control group (P<0.05). Conclusion Age, time from symptom onset to balloon dilation, peak cTnI level, extent of coronary artery lesions, and balloon inflation pressure were identified as independent risk factors affecting myocardial perfusion in STEMI patients after PCI. Compared to simple thrombus aspiration, thrombus aspiration combined with nicorandil demonstrated better improvement in myocardial perfusion, cardiac function, and clinical outcomes for patients with impaired perfusion.

Cardio protective effect of nicorandil in reperfusion injury among patients undergoing primary percutaneous coronary intervention

Objectives

To evaluate the effect of nicorandil in prevention of reperfusion injury during primary percutaneous coronary intervention by thrombolysis in myocardial infarction flow grade scoring.

Methods

A total of 140 patients from Rawalpindi Institute of Cardiology were enrolled in this study conducted from 7th September to 10th of October 2021. These participants were allocated into two major groups. Control group received conventional acute coronary syndrome protocol regimen only whereas experimental group was given nicorandil along with conventional acute coronary syndrome protocol. During primary percutaneous coronary intervention, thrombolysis in myocardial infarction flow grade scoring was analyzed and compared.

Results

Majority of participants in nicorandil group achieved thrombolysis in myocardial infarction Grade-3 scoring which indicated reduced rate of no reflow phenomenon as compared to control group. A statistically significant difference was noted in score of both groups (p value = 0.001) signifying prophylactic use of nicorandil before primary percutaneous coronary intervention along with conventional acute coronary syndrome protocol is superior to only conventional acute coronary syndrome protocol regimen to cases in the control group.

Conclusion

Use of nicorandil in ST elevated myocardial infarction patients before primary percutaneous coronary intervention prevents reperfusion injury thus decreasing the risk of post percutaneous coronary intervention complications and reducing mortality rate in cardiac patients suggesting its significant cardio protective role.

Nicorandil, Novel Potassium Adenosine Triphosphate Channel (K+ ATP) Opener in Ischemia With Non-Obstructive Coronary Arteries (INOCA) and Atherosclerotic Cardiovascular Disease (ASCVD): Delphi Consensus Statement

BACKGROUND

Coronary artery disease (CAD) is a significant health concern today that has assumed epidemic proportions worldwide and in India.

OBJECTIVE

The pathobiology of CAD or ischemia with non-obstructive coronary arteries disease (INOCA) in most cases involves coronary microvascular dysfunction (CMD) that often requires personalized pheno-approach based on the risk stratification and diagnostic yield, especially in patients with recurrent angina episodes. Chronic therapy with anti-anginal is often fraught with challenges of unipolar action, tolerance, and oxidative stress that precludes consistent benefits in clinical cases of CMD represented by microvascular angina (MVA). To further elucidate the clinical role and relevance of long-term vasodilator therapy, including nicorandil, a Knowledge, Attitude, and Perception (KAP) survey was planned to be conducted.

METHODS

Based on responses to the KAP survey questionnaire, Delphi-mediated graded recommendations were developed by a specialist panel as per Agency of Health Care and Quality Systems (AHRQ) criteria.

RESULTS

Management of INOCA with MVA requires a multidisciplinary approach involving non- or invasive procedures that may be relevant for persistent or refractory angina before instituting symptomatic and long-term use of nicorandil for beta-blocker intolerant and associated clinical phenotypes.

CONCLUSION

The analyses provide a real-life approach to the management of INOCA and angina non-obstructive coronary artery disease (ANOCA) with underlying CMD that may be relevant in outpatient settings in India.

Perforated balloon technique mediated intracoronary delivery of nicorandil to treat coronary no-reflow phenomenon: a novel pharmacological solution to precarious situation

BACKGROUND

Coronary no-reflow (NRF) following percutaneous coronary intervention (PCI) is infrequent but one of the most dreaded complication which results from impaired flow of microvascular bed. It is associated with adverse outcome if flow is not restored. Objective of this study was to find safety, effectiveness and outcome of intracoronary nikorandil (IC) administered using perforated balloon technique (PBT) to reverse NRF.

METHOD

2-4 mg of nicorandil was diluted with 5 ml of normal saline and administered using PBT over 5-minute. Its effectiveness was evaluated after 10 minute qualitatively using TIMI flow and quantitatively corrected TIMI frame count (cTFC) method.

RESULT

Study comprised of 84 patients (out of 1789 patients undergoing PCI between January 2019 and February 2020). Their mean age was 57.8±17.9 years. Following PBT, TIMI III flow was successfully normalized in 71 subjects (84.5%), ten (12%) patients had TIMI II flow and it was not successful in three (3.5%) patients. TIMI flow grade got bettered from 1.03 to 2.58 and cTIMI frame count regressed from 52.9±11 to 16.5±5 (P < 0.001). PBT was well tolerated except short lived drop in blood pressure (n=10; 11.9%).

CONCLUSION

This study, for the first time to the best our knowledge, demonstrated that PBT mediated intracoronary administration of nikorandil distally was rapid, safe, and efficacious method to deal with NRF.

Myocardial protective effect of intracoronary administration of nicorandil and alprostadil via targeted perfusion microcatheter in patients undergoing elective percutaneous coronary intervention: A randomized controlled trial

BACKGROUND

The aim of the study was to evaluate the efficacy of nicorandil and alprostadil on myocardial protection in patients undergoing elective percutaneous coronary intervention (PCI).

METHODS

In this prospective, single-blinded, randomized controlled study, 90 consecutive patients scheduled for elective PCI for de novo coronary lesions were assigned to the nicorandil, alprostadil, and nitroglycerin groups in a 1:1:1 ratio. Drugs were administered intracoronary via a targeted perfusion microcatheter. The primary endpoint was the thrombolysis in myocardial infarction (TIMI) myocardial perfusion frame count (TMPFC). Additionally, the corrected TIMI frame count (cTFC), TIMI myocardial perfusion grade (TMPG), and incidence of periprocedural myocardial injury (PMI) were assessed.

RESULTS

Both nicorandil and alprostadil were significantly effective in reducing TMPFC (114.6 ± 33.7 vs 93.4 ± 30.9, P = .016; 114.3 ± 34.3 vs 94.7 ± 33.3, P = .029, respectively). Similar findings were observed in the improvement of cTFC (20.3 ± 10.5 vs 13.5 ± 5.0, P = .003; 20.2 ± 7.4 vs 15.2 ± 5.2, P = .003, respectively) and percentage of TMPG 3 (100% vs 82.8%, P = .052; 83.3% vs 96.7%, P = .196, respectively); whereas, nitroglycerin produced a limited effect on TMPFC (114.4 ± 30.9 vs 112.1 ± 31.9, P = .739), cTFC (19.4 ± 7.2 vs 19.3 ± 7.2, P = .936), and percentage of TMPG 3 (86.7% vs 86.7%, P = 1.000). No significant difference was found in the incidence of PMI (16.7% vs 16.0% vs 27.6%, P = .537), though it was comparatively lower in the nicorandil and alprostadil groups. Furthermore, the intracoronary administration of nicorandil and alprostadil had a mild effect on blood pressure and heart rate.

CONCLUSIONS

The intracoronary administration of nicorandil and alprostadil via a targeted perfusion microcatheter was more effective in improving myocardial perfusion in patients undergoing elective PCI than nitroglycerin.

Nicorandil inhibits cardiomyocyte apoptosis and improves cardiac function by suppressing the HtrA2/XIAP/PARP signaling after coronary microembolization in rats

Cardiomyocyte apoptosis is a key factor in the deterioration of cardiac function after coronary microembolization (CME). Nicorandil (NIC) affects myocardial injury, which may be related to the inhibition of apoptosis. However, the specific mechanism of cardioprotection has not been elucidated. Therefore, we analyzed the impact of NIC on cardiac function in rats subjected to CME and its effect on the high-temperature requirement peptidase 2/X-linked inhibitor of apoptosis protein/poly ADP-ribose polymerase (HtrA2/XIAP/PARP) pathway. Sprague Dawley rats were divided into four groups: Sham, CME, CME + NIC, and CME + UCF. Echocardiography was performed 9 hours after CME. Myocardial injury markers were evaluated in blood samples, and the heart tissue was collected for hematoxylin-eosin staining, hematoxylin basic fuchsin picric acid staining staining, TdT-mediated DUTP nick end labeling (TUNEL) staining, Western blot analysis of the HtrA2/XIAP/PARP pathway, and transmission electron microscopy. NIC ameliorated cardiac dysfunctioncaused by CME and reduced serum levels of CK-MB and LDH. In addition, NIC decreased myocardial microinfarct size and apoptotic index. NIC reduced the Bax/Bcl-2 ratio, levels of cleaved caspase 3/9, cytoplasmic HtrA2, and cleaved PARP, and increased the level of XIAP. The effects of NIC were similar to those of the HtrA2 inhibitor, UCF101. This study demonstrated that NIC reduces CME-induced myocardial injury, reduces mitochondrial damage, and improves myocardial function. The reduction in cardiomyocyte apoptosis by NIC may be mediated by the HtrA2/XIAP/PARP signaling pathway.

The impact of oral nicorandil pre-treatment on ST resolution and clinical outcome of patients with acute ST-segment elevation myocardial infarction undergoing primary coronary angioplasty: A randomized placebo controlled trial

Introduction: Literature has shown the effects of intravenous/intracoronary nicorandil on increased myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI) treated with mechanical reperfusion. However, the possible cardioprotective effect of oral nicorandil on the clinical outcome prior to primary coronary angioplasty is not well documented. Our aim was to assess the effect of oral nicorandil on primary percutaneous coronary intervention (PPCI).

Methods: A total of 240 patients with acute STEMI undergoing PPCI were randomly assigned to oral nicorandil (Intervention, n=116) and placebo (Control, n=124) groups. The intervention group received 20 mg oral nicorandil at the emergency department and another 20 mg oral nicorandil in the catheterization laboratory just before the procedure. The control group received matched placebo. Our primary outcome was ST-segment resolution ≥50% one hour after primary angioplasty. Secondary outcome was in-hospital major adverse cardiovascular events (MACE), defined as a composite of death, ventricular arrhythmia, heart failure and stroke.

Results: In the patients of intervention and control groups, the occurrence of ST-segment resolution ≥ 50% were 68.1% and 62.9% respectively, (P =0.27). In-hospital MACE occurred less frequently in the intervention group, compared to placebo group (11.2% vs. 22.5%, P =0.012).

Conclusion: Although the administration of oral nicorandil before primary coronary angioplasty did not improve ST-segment resolution in patients with acute STEMI, its promoting effects was remarkable on in-hospital clinical outcomes.

Clinical Registration:IRCT20140512017666N1

Nicorandil for Periprocedural Myocardial Injury in Elective Percutaneous Coronary Intervention: A Meta-Analysis of 10 Randomized Controlled Trials

The clinical outcomes of nicorandil in percutaneous coronary intervention (PCI) are conflicting. We sought to evaluate the effects of nicorandil on periprocedural myocardial injury (PMI) in elective PCI. Eligible studies that reported the effect of nicorandil on PMI in elective PCI were obtained from PubMed, Web of Science, and Cochrane Library (up to October 28, 2019). The outcomes were PMI and major adverse cardiovascular and cerebrovascular events (MACCEs). Ten randomized controlled trials with 1304 patients undergoing elective PCI were evaluated. Nicorandil significantly reduced the incidence of PMI (odds ratio [OR] = 0.48; P = .0003); however, there was no significant difference in MACCEs (OR = 0.80; P = .45) between the 2 groups. Subgroup analyses showed that nicorandil significantly lowered the PMI risk when only patients with stable coronary artery disease (OR = 0.41; P = .0008) were considered and when nicorandil was administered intravenously (OR = 0.41; P = .0007) or orally (OR = 0.33; P = .0001). This meta-analysis suggests that nicorandil could reduce the incidence of PMI without increasing the occurrence of MACCEs in elective PCI. The effect of nicorandil in lowering the PMI risk is associated with the diagnosis of the patients and the route of nicorandil administration.

Effects of Intracoronary Nicorandil on Myocardial Microcirculation and Clinical Outcomes in Patients with Acute Myocardial Infarction: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The amelioration of myocardial reperfusion in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PPCI) remains a significant issue.

OBJECTIVE

We conducted a meta-analysis of randomized controlled trials (RCTs) to better assess the effects of intracoronary nicorandil administration on myocardial microcirculation and clinical outcomes in these patients.

METHODS

The meta-analysis was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. A literature search was performed in the PubMed, Embase, Cochrane Library, and Web of Science databases up to April 2019, with no time or language limitations. Pooled risk ratios (RRs) were calculated to evaluate the treatment effects.

RESULTS

Seven RCTs involving a total of 562 patients were included. Compared with control, intracoronary nicorandil significantly reduced the incidence of thrombolysis in myocardial infarction (TIMI) grade ≤ 2 (RR 0.349; 95% confidence interval [CI] 0.199-0.611; P < 0.001) and TIMI myocardial perfusion grade ≤ 2 (RR 0.611; 95% CI 0.438-0.852; P = 0.004) and was associated with higher complete ST-segment resolution rates (RR 1.326; 95% CI 1.090-1.614; P = 0.005). However, no significant benefits were observed on clinical outcomes, including death (RR 0.370; 95% CI 0.085-1.618; P = 0.187), recurrent myocardial infarction (RR 0.507; 95% CI 0.156-1.655; P = 0.261), heart failure (RR 0.528; 95% CI 0.224-1.247; P = 0.145), and target lesion/vessel revascularization (RR 1.109; 95% CI 0.553-2.224; P = 0.770).

CONCLUSIONS

Intracoronary nicorandil can significantly improve myocardial microcirculation in patients with AMI undergoing PPCI, but it failed to offer clinically significant benefits.

Factors Influencing Stent Restenosis After Percutaneous Coronary Intervention in Patients with Coronary Heart Disease: A Clinical Trial Based on 1-Year Follow-Up

BACKGROUND This study observed the incidence of in-stent restenosis (ISR) after percutaneous coronary intervention (PCI) and discusses the risk factors of ISR based on clinical data, coronary angiography, and stent features, to provide a theoretical basis for the prevention and treatment of ISR. MATERIAL AND METHODS We selected 1132 cases who received stent implantation at the Shaanxi People's Hospital from June 2014 to June 2016 and were followed up by coronary angiography within 1 year. Based on coronary angiography, the cases were divided into ISR and non-ISR groups. ISR was defined as a reduction in lumen diameter by over 50% after PCI. The ISR group consisted of 93 cases and the non-ISR group consisted of 1039 cases. Medical history, biochemical indicators, features of coronary artery lesions, and stent status were analyzed retrospectively. Risk factors of ISR were identified by univariate and multivariate logistic regression analyses. RESULTS Among 1132 cases, 93 cases had ISR, with the overall incidence of 8.21%. Univariate and multivariate logistic regression analyses indicated that postoperative hypersensitive C-reactive protein (hs-CRP) levels (OR=2.309, 1.579-3.375 mg/L), postoperative homocysteine (HCY) levels (OR=2.202, 1.268-3.826 μmol/L), history of diabetes (OR=1.955,1.272-3.003), coronary bifurcation lesions (OR=3.785, 2.246-6.377), and stent length (OR=1.269, 1.179-1.365 mm) were independent risk factors of ISR after PCI (P<0.05). CONCLUSIONS Elevated hs-CRP and HCY levels after PCI, history of diabetes, coronary bifurcation lesions, and greater stent length were associated with a higher risk of ISR. Patients with a higher risk of ISR should receive routine follow-up and intense medication management after PCI to control the risk factors and to reduce ISR.

Effects of mitochondrial ATP-sensitive potassium channel activation (nicorandil) in patients with angina pectoris undergoing elective percutaneous coronary interventions: A meta-analysis of randomized controlled trials

AIMS

Nicorandil, which is a mitochondrial ATP-sensitive potassium channel opener, is believed to improve perioperative myocardial injury (PMI) in patients undergoing percutaneous coronary intervention (PCI), but recent studies have shown that nicorandil treatment did not improve functional and clinical outcomes in patients with angina pectoris who underwent elective PCI. We performed a meta-analysis to investigate the protective effect of nicorandil on perioperative injury in patients with angina pectoris who underwent elective PCI.

METHODS

The Medline, EMBASE, and Cochrane databases were searched for randomized clinical trials examining the effects of nicorandil. Two investigators independently selected suitable trials, extracted data, and assessed trial quality.

RESULTS

Seven studies of patients undergoing elective PCI, comprising a total of 979 patients, were included in this review. The results showed that nicorandil did not reduce the levels of markers of myocardial injury (standardized mean difference [SMD] 0.31 [95%CI -0.6, 1.22] for creatine kinase-MB [CK-MB] and 1.29 [95%CI -2.18, 4.76] for troponin I [TNI]), perioperative complications (relative risk [RR] 0.91 [95%CI 0.46-1.81]), target vessel revascularization (RR 0.79 [95%CI 0.50-1.25]) or major adverse cardiac events (MACE) (RR 0.83 [95%CI 0.49-1.43]). Nicorandil did reduce the corrected TIMI frame count (SMD-0.30 [95%CI -0.52, -0.09]).

CONCLUSION

Although nicorandil did not reduce the overall incidence of perioperative complications and the incidence of major adverse cardiac events (MACE) in patients with angina pectoris who underwent elective PCI, it could still improve no reflow and slow coronary flow.

Exploring potential biomarkers of coronary heart disease treated by Jing Zhi Guan Xin Pian using high-throughput metabolomics

Coronary heart disease (CHD) is a relatively complex disease characterized by narrowing of the arterial lumen and reduction of blood flow to the heart. There is no effective early diagnosis and prevention method. Jing Zhi Guan Xin Pian (JZGXP) is a new preparation prepared from the effective extract of Guanxin II. It is made of five components of traditional Chinese medicine and functions by promoting blood circulation and removing blood stasis and is used for the treatment of CHD and angina pectoris. In our study, a CHD rat model was prepared using a high-fat diet combined with intraperitoneal injection of vitamin D3. Clinical biochemical indexes (TG, CHO and HDL-C), histopathology (coronary and myocardial tissue), electrocardiogram and cardiac indexes were used to evaluate the efficacy of JZGXP in the treatment of CHD model rats. UPLC-HDMS-based metabolomics techniques were used to find metabolic profiles, biomarkers and related metabolic pathways in CHD models and to evaluate the effects of JZGXP on them. At the same time, the targets of JZGXP for the treatment of CHD were analyzed. Our study ultimately identified 25 biomarkers associated with CHD models. Further studies found that these 25 biomarkers involved 9 metabolic pathways in the body and found that JZGXP can recall 21 biomarkers in the urine of model rats and these biomarkers involve nine metabolic pathways. Finally, the targets of JZGXP for the treatment of CHD were β-alanine metabolism and tyrosine metabolism, i.e. amino acids metabolism. This study showed that metabolomics technology is effective for exploring potential biomarkers associated with syndromes or diseases and the therapeutic mechanisms of a traditional Chinese medicine formulation.

Coronary heart disease (CHD) is a relatively complex disease characterized by narrowing of the arterial lumen and reduction of blood flow to the heart.

Prognostic Value of Hemoglobin A1c Levels in Postmenopausal Diabetic Patients Undergoing Percutaneous Coronary Intervention (PCI) for Acute Coronary Syndrome

Background

The purpose of our study was to analyze the clinical value of glycosylated hemoglobin Alc (HbA1c) levels in postmenopausal women with acute coronary syndrome (ACS) and diabetes following percutaneous coronary intervention (PCI).

Material/Methods

A total of 173 consecutive postmenopausal patients with comorbid diabetes underwent PCI for primary ACS were enrolled in this study. Serum HbA1c levels were measured prior to PCI, and baseline clinical characteristics of all patients were collected. All patients were followed up at regular intervals for major adverse cardiovascular events (MACEs) during the first year after PCI. MACEs included cardiac death, non-fatal myocardial infarction, and target vessel revascularization (TVR).

Results

At the endpoint of this study, 29 (16.8%) patients out of all 173 patients had MACEs. According to the effect of glycemic control (as indicated by HbA1c levels), all patients were stratified into a well-controlled group (HbA1c ≤7.0%, N=72) and a poorly-controlled group (HbA1c >7.0%, N=101). The incidence rate of MACEs and TVR in poorly-controlled diabetics was prominently higher than that in well-controlled diabetics (10.8% vs. 21.8%, p=0.04). In multivariable COX regression analysis, after adjustment for potential confounders, HbA1c ≥7.0% remained an independent risk predictor of MACE (HR, 2.17; 95%CI, 1.13–5.65; p<0.01).

Conclusions

In postmenopausal ACS patients with comorbid diabetes, a high level of HbA1c is associated with a higher MACE rate after PCI, which is mainly driven by a higher rate of TVR.

No-reflow phenomenon in the heart and brain

The no-reflow phenomenon refers to the observation that when an organ is made ischemic by occlusion of a large artery supplying it, restoration of patency in that artery does not restore perfusion to the microvasculature supplying the parenchyma of that organ. This has been observed after prolonged arterial occlusions in the heart (30–90 min), brain, skin, and kidney. In experimental models, zones of no reflow in the heart are characterized by ultrastructural microvascular damage, including focal endothelial swelling obstructing the lumen of small vessels. Blood elements such as neutrophil plugs, platelets, and stacking of erythrocytes have also been implicated. No reflow is associated with poor healing of the myocardial infarction. In patients, no reflow is associated with a poor clinical outcome independent of infarct size, suggesting that therapy for no reflow may be an important approach to improving outcome for ST elevation myocardial infarction. No reflow occurs after reperfusion of experimental cerebral ischemia and may be observed after only 5-min episodes of ischemia. Aggregation of blood elements may play a greater role than in cardiac no reflow. No reflow in the brain may involve cortical spreading depression with disturbed local vascular control and high, vasculotonic levels of extracellular K+ concentration, postischemic swelling in endothelial cells and abutting end feet of pericytes, pericyte contraction and death, interstitial edema with collapse of cerebral capillaries, and inflammatory reaction. New guidelines suggesting that reperfusion for stroke may be considered as late as 24 h after the onset of symptoms suggest that clinicians may be seeing more no reflow in the future.

Role of TLR4/MyD88/NF-κB signaling pathway in coronary microembolization-induced myocardial injury prevented and treated with nicorandil

Coronary microembolization (CME) is a common complication during the treatment of acute coronary syndrome (ACS) and percutaneous coronary intervention (PCI). Nicorandil can be used to prevent myocardial injury after PCI to reduce the incidence of coronary no-reflow and slow flow, and play a role in myocardial protection, suggesting that its mechanism may be related to the inhibition of CME-induced inflammation of cardiomyocytes. However, the specific mechanism remains unclear. This study investigated the myocardial protective effects of nicorandil pretreatment on CME-induced myocardial injury and the specific mechanism of its inhibition of myocardial inflammation. An CME rat model exhibited CME-induced myocardial inflammation and the elevation of serum tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-1β based on echocardiography, myocardial enzyme detection, hematoxylin and eosin (HE) and hematoxylin-basic fuchsin-picric acid (HBFP) stainings, ELISA, quantitative real-time PCR, and western blotting. Nicorandil treatment seven days before CME induction effectively inhibited myocardial inflammation, ameliorated myocardial injury, and improved cardiac function, mainly by inhibiting Toll-like receptor 4 (TLR4)-mediated myeloid differentiation primary response protein 88 (MyD88)-dependent nuclear factor-kappa B (NF-κB) signaling. Rat neonatal cardiomyocyte experiments further confirmed that nicorandil ameliorated lipopolysaccharide (LPS)-induced myocardial inflammation and improved cardiomyocyte survival. The specific mechanisms mainly involved the inhibition of TLR4/MyD88/NF-κB signaling and the reduction of the inflammatory cytokines TNF-α and IL-1β released from cardiomyocytes. In summary, nicorandil significantly protected cardiomyocytes from CME-induced myocardial injury mainly by inhibiting TLR4/MyD88/NF-κB signaling, thereby reducing the onset of CME-induced myocardial inflammation. This could be one of the important mechanisms for reducing postoperative myocardial injury via PCI-preoperative prophylactic treatment with nicorandil.

Intracoronary Nicorandil and the Prevention of the No-Reflow Phenomenon During Primary Percutaneous Coronary Intervention in Patients with Acute ST-Segment Elevation Myocardial Infarction

Background

This study aimed to investigate intracoronary nicorandil treatment on the no-reflow phenomenon (NRP) during primary percutaneous coronary intervention (PCI) in patients with acute ST-segment elevation myocardial infarction (STEMI) and to compare nicorandil with sodium nitroprusside.

Material/Methods

Patients with sustained acute STEMI who underwent primary PCI (N=120) were randomly assigned to three groups: the nicorandil-treated group (N=40) had 2 mg of nicorandil injected into the coronary artery at 2 mm beyond the occlusion with balloon pre-dilation; the sodium nitroprusside-treated group (N=40) underwent the same procedure, but with 200 μg of sodium nitroprusside; the control group (N=40) received PCI and balloon pre-dilation only. Coronary angiography, incidence of NRP, hypotensive episodes, ST-segment resolution (STR) rate, levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), creatine kinase-MB (CK-MB), cardiac troponin I (cTnI), wall motion score index (WMSI), and left ventricular ejection fraction (LVEF) were measured before and after primary PCI. Major adverse cardiovascular events (MACEs) post-PCI and at three-month follow-up were recorded.

Results

Patients in the sodium nitroprusside and nicorandil groups had significantly improved thrombolysis in myocardial infarction (TIMI) scores, TIMI myocardial perfusion grade (TMPG), and ST-segment elevation resolution (STR) (P<0.05), and a significantly lower incidence of NRP (P=0.013). The incidence of intraoperative hypotension in the sodium nitroprusside group was significantly greater than the nicorandil and control groups (P=0.035).

Conclusions

Patients with sustained acute STEMI undergoing primary PCI, treated with intracoronary nicorandil had a reduced incidence of the NRP, improved myocardial perfusion and cardiac function.

Inotropic Effects of Nicorandil on Cardiac Contractility Assessed by Left Ventricular Pressure-Volume Relationship Analyses in Anesthetized Monkeys

Nicorandil is a representative antianginal drug that has dual properties of a nitrate and adenosine triphosphate-sensitive potassium (KATP) channel agonist; however, its effects on integrated cardiac function have not been fully understood. This study was conducted to clarify the functional, hemodynamic, and electrophysiological effects of nicorandil using ventricular pressure-volume loop analysis in isoflurane-anesthetized monkeys. Nicorandil was given intravenously at therapeutic doses of 0.2 and 2 mg/kg over 10 minutes to cynomolgus monkeys (n = 5) with a pause of 10 minutes between the 2 doses. Nicorandil at 0.2 mg/kg caused decreases in systemic blood pressure and left ventricular end-diastolic pressure by its vasodilating action. Nicorandil at 2 mg/kg also exhibited positive inotropic action demonstrated by increased slopes of preload recruitable stroke work relationship, which is a load-independent inotropic parameter. In load-dependent inotropic parameters, positive inotropy of nicorandil was also indicated by the shortened QA interval and increased contractility index; however, significant changes were not observed in the maximal upstroke velocity of left ventricular pressure. Moreover, reflex tachycardia accompanied by shortening of QT/QTc intervals was observed. Overall, the isoflurane-anesthetized monkey model with pressure-volume loop analysis revealed cardiac variables of nicorandil, including a positive inotropy contributable to cardiac performance in addition to its vasodilatory effect. These findings provide useful information when considering the prescription of nicorandil in patients.

Renoprotective effect of nicorandil in patients undergoing percutaneous coronary intervention: a meta-analysis of 4 randomized controlled trials

Many studies have evaluated the renoprotective effect of nicorandil in patients undergoing percutaneous coronary intervention (PCI), but the results are inconsistent. We therefore conducted this meta-analysis to evaluate the protective effect of nicorandil against contrast-induced nephropathy (CIN). We searched PubMed, Embase, the Cochrane Library, Web of Science, and clinical trials database. Studies compared the nicorandil (plus hydration) with hydration alone in patients receiving PCI were eligible. The primary outcome was the incidence of CIN. Four randomized controlled trials (RCTs) with 730 patients were included. All enrolled patients were with renal dysfunction or with moderate risk for CIN. Meta-analysis showed that nicorandil was associated with a decrease of CIN (odds ratio 0.33, 95% confidence interval [CI], 0.19~0.58, p < 0.001), without heterogeneity across the studies (I² = 33.7%, p = 0.210). Moreover, nicorandil treatment could significantly reduce the level of serum creatinine, estimated glomerular filtration rate and cystatin C at 48 hours after procedures (standardized mean difference [SMD] -0.17, 95%CI -0.33~-0.01; SMD 0.29, 95% CI 0.11~0.48; SMD -0.17, 95%CI -0.33~-0.01, respectively). Nicorandil can reduce the incidence of CIN and result in favorable changes in renal function in patients undergoing PCI. More RCTs with large sample size and high quality are needed to confirm our results.