Coronary microvascular obstruction and dysfunction in patients with acute myocardial infarction

Despite prompt epicardial recanalization in patients presenting with ST-segment elevation myocardial infarction (STEMI), coronary microvascular obstruction and dysfunction (CMVO) is still fairly common and is associated with poor prognosis. Various pharmacological and mechanical strategies to treat CMVO have been proposed, but the positive results reported in preclinical and small proof-of-concept studies have not translated into benefits in large clinical trials conducted in the modern treatment setting of patients with STEMI. Therefore, the optimal management of these patients remains a topic of debate. In this Review, we appraise the pathophysiological mechanisms of CMVO, explore the evidence and provide future perspectives on strategies to be implemented to reduce the incidence of CMVO and improve prognosis in patients with STEMI.

Mechanism of action and neuroprotective role of nicorandil in ischemic stroke

Nicorandil is a dual mechanism anti-anginal agent that acts as a nitric oxide (NO) donor and a potassium (K+) channel opener. Recent studies have evaluated the effect of nicorandil on ischemic stroke. Neurons have a low tolerance to hypoxia and therefore the brain tissue is significantly vulnerable to ischemia. Current approved treatments for ischemic stroke are tissue plasminogen activators and clot retrieval methods. The narrow therapeutic time window and lack of efficacy in restoring the dying neurons urge researchers to develop an alternative approach. In the terminal stages of anoxia, K+ channels induce hyperpolarization in various types of neuronal cells, leading to decreased neuronal activity and the preservation of the brain's energy. Nicorandil can open these K+ channels and sustain the hyperpolarization phase, which may have a neuroprotective effect during hypoxia. Additionally, we review how nicorandil can improve overall stroke outcomes through its anti-inflammatory, anti-oxidative, and edema-reducing effects. One of the major components evaluated in stroke patients is blood pressure. Studies have demonstrated that the effect of nicorandil on blood pressure is related to both its K+ channel opening and NO donating mechanisms. Since both hypertension and hypotension need correction before stroke intervention, it's crucial to consider the role of nicorandil and its impact on blood pressure. Previously published studies indicate that the right dosage of nicorandil can improve cerebral blood flow without significant changes in hemodynamic profiles. In this review, we discuss how nicorandil may contribute to better stroke outcomes based on previously published literature and laboratory findings.

The effect of nicorandil on cardiac function and clinical outcomes in ST-segment elevation myocardial infarction patients undergoing primary percutaneous coronary intervention: a randomised trial

BACKGROUND

We investigated the effect of nicorandil on infarct size, cardiac function assessed by cardiac magnetic resonance imaging (CMR) and outcomes in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI).

METHODS

In a prospective, randomised, controlled trial, 83 patients with STEMI receiving primary PCI were randomised into the nicorandil (n =  40) or placebo (n  =  43) groups. Nicorandil was administered in the emergency room before primary PCI as an intravenous bolus of 4 mg followed by a continuous infusion of 6 mg/h for 24 h and as 2-mg intracoronary injections prior to balloon dilatation and coronary stenting. Nicorandil was continued orally at 10-20 mg/d for 6 months. Infarct size and cardiac function were measured by CMR at 5 d and 6 months after primary PCI. Furthermore, major adverse cardiac events (MACEs) including all-cause death, nonfatal myocardial infarction (MI), any revascularisation, stroke, and definite/probable stent thrombosis (ST) were compared.

RESULTS

There were no significant differences in baseline clinical characteristics between the groups. Infarct size at baseline and 6 months as well as infarct size changes during 6 months as measured by CMR were similar between the groups. Similarly, other CMR parameters were comparable at baseline and 6 months between the groups. MACEs occurred in four patients (4.8%) during 6 months. No significant difference in the risk of MACEs was observed between the groups.

CONCLUSIONS

Treatment with nicorandil for 6 months after primary PCI was not associated with any improvement in infarct size, CMR-determined cardiac function, and outcomes in STEMI patients.

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.

Nicorandil Suppresses Ischemia-Induced Norepinephrine Release and Ventricular Arrhythmias in Hypertrophic Hearts

PURPOSE

Ventricular arrhythmias (VAs) are a common cause of sudden death in acute myocardial infarction (MI), for which hypertension is a major risk factor. Nicorandil opens ATP-sensitive potassium (KATP) channels, which are expressed by nerve terminals and cardiomyocytes and regulate the release of norepinephrine (NE). However, the effects of nicorandil on ischemic NE release in cardiac tissue remain unclear. Therefore, we herein investigated whether nicorandil suppressed interstitial NE concentrations and VAs during acute MI in pressure overload-induced hypertrophic hearts.

METHODS

Rats were divided into two groups: an abdominal aortic constriction (AAC) group and sham-operated (Sham) group. Four weeks after constriction, cardiac geometry and functions were examined using echocardiography and hemodynamic analyses. Myocardial ischemia was induced by coronary artery occlusion for 100 min with or without the administration of nicorandil. VAs were assessed by electrocardiography, and NE concentrations in the ischemic region were measured using a micro-dialysis method.

RESULTS

AAC induced left ventricular hypertrophy with diastolic dysfunction. VAs markedly increased in the early phase (0-20 min) of ischemia in both groups and were more frequent in the AAC group. Cardiac interstitial NE concentrations were higher in the AAC group before ischemia and significantly increased during ischemia in both groups. Nicorandil significantly suppressed ischemia-induced VAs and NE increases in the AAC group.

CONCLUSION

Ischemia-induced VAs were more frequent in hypertrophic hearts and associated with high interstitial concentrations of NE. The attenuation of ischemia-induced increases in NE through neuronal KATP opening by nicorandil may suppress ischemia-induced VAs in hypertrophic hearts.

Reperfusion injury in acute ischemic stroke: Tackling the irony of revascularization

Reperfusion injury is an unfortunate consequence of restoring blood flow to tissue after a period of ischemia. This phenomenon can occur in any organ, although it has been best studied in cardiac cells. Based on cardiovascular studies, neuroprotective strategies have been developed. The molecular biology of reperfusion injury remains to be fully elucidated involving several mechanisms, however these mechanisms all converge on a similar final common pathway: blood brain barrier disruption. This results in an inflammatory cascade that ultimately leads to a loss of cerebral autoregulation and clinical worsening. In this article, the authors present an overview of these mechanisms and the current strategies being employed to minimize injury after restoration of blood flow to compromised cerebral territories.

Intracoronary nicorandil induced hyperemia for physiological assessments in the coronary artery lesions

OBJECTIVE

Maximal hyperemia is a key element of invasive physiological examination. The aim of this study was to investigate the efficacy and safety of intracoronary (IC) nicorandil in comparison with adenosine 5'-triphosphate (ATP) intravenous (i.v.) injection for fractional flow reserve (FFR) measurement in coronary artery lesions.

MATERIALS AND METHODS

In this study, 46 patients who had their FFR measured were enrolled, including 51 lesions. Hyperemia was induced by bolus 2 mg nicorandil and ATP (40 mg ATP + 36 ml saline, weight × 10 ml/h) for FFR measurement. The safety and efficacy of IC nicorandil were evaluated.

RESULTS

The mean FFR values measured by nicorandil and ATP were 0.810 ± 0.013 and 0.799 ± 0.099, p < 0.001, respectively. There was a strong correlation between FFR measured by nicorandil and ATP (r = 0.983, R 2 = 0.966, FFRnicorandil = 0.937 × FFRATP + 0.061). The rate of FFR ≤ 0.75 in the nicorandil and ATP groups was 31.37 vs. 35.29%, respectively (p = 0.841), the consistency rate was 96.08%; the FFR ≤ 0.8 rate was 41.18 and 43.14%, respectively (p = 0.674), and the consistency rate was 90.20%. In five lesions, the FFR value measured by nicorandil ranged between 0.79 and 0.82, indicating inconsistency according to FFR ≤ 0.8. The blood pressure changes caused by nicorandil and ATP were 12.96 ± 6.83 and 22.22 ± 11.44 mmHg (p < 0.001); the heart rate changes were 2.43 ± 1.31 and 6.52 ± 2.87 beats/min, respectively (p < 0.001); and the PR interval changes were 6.0 (1.0-11.0) and 9.0 (2.0-19.0) ms, respectively (p < 0.001). Visual analog scale (VAS) scores in the nicorandil group were all in the range 0-2, while in the ATP group were mostly in the range of 3-5.

CONCLUSION

Intracoronary bolus of nicorandil (2 mg) infusion induces stable hyperemia, and it could be considered as an alternative drug to ATP for FFR measurement with a lower side effect profile in most patients.

Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: The CHANGE Trial

Background Nicorandil was reported to improve microvascular dysfunction and reduce reperfusion injury when administered before primary percutaneous coronary intervention. In this multicenter, prospective, randomized, double-blind clinical trial (CHANGE [Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention]), we investigated the effects of nicorandil administration on infarct size in patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention. Methods and Results A total of 238 patients with ST-segment-elevation myocardial infarction were randomized to receive intravenous nicorandil (n=120) or placebo (n=118) before reperfusion. Patients in the nicorandil group received a 6-mg intravenous bolus of nicorandil followed by continuous infusion at a rate of 6 mg/h. Patients in the placebo group received the same dose of placebo. The predefined primary end point was infarct size on cardiac magnetic resonance (CMR) imaging performed at 5 to 7 days and 6 months after reperfusion. CMR imaging was performed in 201 patients (84%). Infarct size on CMR imaging at 5 to 7 days after reperfusion was significantly smaller in the nicorandil group compared with the placebo (control) group (26.5±17.1 g versus 32.4±19.3 g; P=0.022), and the effect remained significant on long-term CMR imaging at 6 months after reperfusion (19.5±14.4 g versus 25.7±15.4 g; P=0.008). The incidence of no-reflow/slow-flow phenomenon during primary percutaneous coronary intervention was much lower in the nicorandil group (9.2% [11/120] versus 26.3% [31/118]; P=0.001), and thus, complete ST-segment resolution was more frequently observed in the nicorandil group (90.8% [109/120] versus 78.0% [92/118]; P=0.006). Left ventricular ejection fraction on CMR imaging was significantly higher in the nicorandil group than in the placebo group at both 5 to 7 days (47.0±10.2% versus 43.3±10.0%; P=0.011) and 6 months (50.1±9.7% versus 46.4±8.5%; P=0.009) after reperfusion. Conclusions In the present trial, administration of nicorandil before primary percutaneous coronary intervention led to improved myocardial perfusion grade, increased left ventricular ejection fraction, and reduced myocardial infarct size in patients with ST-segment-elevation myocardial infarction. Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT03445728.

The effectiveness of alprostadil in treating coronary microcirculation dysfunction following ST-segment elevation myocardial infarction in a pig model

Though alprostadil has been reported to improve the impaired microcirculation of patients with pulmonary arterial hypertension, its effectiveness as a treatment for coronary microvasculature dysfunction (CMD) following ST-segment elevation myocardial infarction (STEMI) is unknown. A total of 18 miniature pigs with CMD following STEMI were randomized into three groups that received an intracoronary injection of 5 ml of normal saline, 2 mg of nicorandil or 10 µg of alprostadil immediately after measurement of the index of microcirculatory resistance (IMR) and then an intravenous drip containing 5 ml of normal saline, 2 mg of nicorandil or 10 µg of alprostadil once a day for 6 days. The IMR, cardiac function using ultrasound, infarct areas and heparanase levels in infarct areas were measured and compared between the three groups. The IMR decreased markedly 10 min after alprostadil or nicorandil intracoronary injection (both P<0.05) but not following saline injection (P>0.05). After 7 days, the IMR was substantially lower in the alprostadil and nicorandil groups compared with the saline group (both P<0.05) and the ejection fraction was considerably higher in the alprostadil and nicorandil groups compared with the saline group (both P<0.05). Differences in infarct areas and the relative heparanase expression levels among the 3 groups were similar to the differences in the ejection fraction. No significant differences in the above assessment indexes were identified in the alprostadil and nicorandil groups. Alprostadil infusion improved coronary microcirculation function, reduced the infarct area and limited left ventricular dilatation in a pig coronary microvasculature dysfunction model following STEMI.

Clinical outcomes of nicorandil administration in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Primary percutaneous coronary intervention is the treatment of choice in ST-segment elevation myocardial infarction and no-reflow phenomenon is still an unsolved problem.

METHODS

We searched PubMed, EmBase, and Cochrane Central Register of Controlled Trials for relevant randomized controlled trials. The primary endpoint was the incidence of major adverse cardiac events and the secondary endpoint was the incidences of no-reflow phenomenon and complete resolution of ST-segment elevation.

RESULTS

Eighteen randomized controlled trials were enrolled. Nicorandil significantly reduced the incidence of no-reflow phenomenon (OR, 0.46; 95% CI, 0.36-0.59; P < 0.001; I² = 0%) and major adverse cardiac events (OR, 0.42; 95% CI, 0.27-0.64; P < 0.001; I² = 52%). For every single outcome of major adverse cardiac events, only heart failure and ventricular arrhythmia were significantly improved with no heterogeneity (OR, 0.36; 95% CI, 0.23-0.57, P < 0.001; OR, 0.43; 95% CI, 0.31-0.60, P < 0.001 respectively). A combination of intracoronary and intravenous nicorandil administration significantly reduced the incidence of major adverse cardiac events with no heterogeneity (OR, 0.24; 95% CI, 0.13-0.43, P < 0.001; I² = 0%), while a single intravenous administration could not (OR, 0.66; 95% CI, 0.40-1.06, P = 0.09; I² = 52%).

CONCLUSIONS

Nicorandil can significantly improve no-reflow phenomenon and major adverse cardiac events in patients undergoing primary percutaneous coronary intervention. The beneficial effects on major adverse cardiac events might be driven by the improvements of heart failure and ventricular arrhythmia. A combination of intracoronary and intravenous administration might be an optimal usage of nicorandil.

Novel Combined Antioxidant Strategy against Hypertension, Acute Myocardial Infarction and Postoperative Atrial Fibrillation

Reactive oxygen species (ROS) play a physiological role in the modulation of several functions of the vascular wall; however, increased ROS have detrimental effects. Hence, oxidative stress has pathophysiological impacts on the control of the vascular tone and cardiac functions. Recent experimental studies reported the involvement of increased ROS in the mechanism of hypertension, as this disorder associates with increased production of pro-oxidants and decreased bioavailability of antioxidants. In addition, increased ROS exposure is found in ischemia-reperfusion, occurring in acute myocardial infarction and cardiac surgery with extracorporeal circulation, among other settings. Although these effects cause major heart damage, at present, there is no available treatment. Therefore, it should be expected that antioxidants counteract the oxidative processes, thereby being suitable against cardiovascular disease. Nevertheless, although numerous experimental studies agree with this notion, interventional trials have provided mixed results. A better knowledge of ROS modulation and their specific interaction with the molecular targets should contribute to the development of novel multitarget antioxidant effective therapeutic strategies. The complex multifactorial nature of hypertension, acute myocardial infarction, and postoperative atrial fibrillation needs a multitarget antioxidant strategy, which may give rise to additive or synergic protective effects to achieve optimal cardioprotection.

Effect of nicorandil treatment adjunctive to percutaneous coronary intervention in patients with acute myocardial infarction: a systematic review and meta-analysis

Objective

There is controversy whether nicorandil treatment has cardioprotective effects in patients with acute myocardial infarction (AMI) following percutaneous coronary intervention (PCI). This meta-analysis was conducted to assess the efficacy of nicorandil on functional and clinical outcomes after PCI.

Methods

Systematic databases were searched to retrieve studies that compared the effect of nicorandil with a control group in patients with AMI who underwent PCI. Outcomes related to coronary blood flow, and functional and clinical outcomes were extracted and a meta-analysis was performed. Trial sequential analysis was conducted to estimate the required sample size for statistical power.

Results

Twenty-four trials involving 2965 patients with AMI were enrolled. Pooled results showed that nicorandil treatment significantly suppressed the incidence of no-reflow phenomenon and reperfusion arrhythmia after reperfusion, improved the left ventricular ejection fraction and left ventricular end-systolic volume index, and reduced major adverse cardiovascular events and cardiovascular death. Trial sequential analysis confirmed the effect of nicorandil in reducing the incidence of no-reflow phenomenon and follow-up major adverse cardiovascular events in patients with AMI after PCI.

Conclusion

Our findings suggest that nicorandil treatment adjunctive to reperfusion therapy improves myocardial reperfusion, cardiac function, and clinical outcomes in patients with AMI.

Impact of administration of nicorandil prior to percutaneous coronary intervention in treatment of acute myocardial infarction: A protocol for systematic review and meta-analysis

BACKGROUND

In order to provide new evidence-based medical evidence for clinical treatment, we undertook a systematic review and meta-analysis to assess the efficacy and safety of nicorandil prior to percutaneous coronary intervention in acute myocardial infarction (AMI) patients.

METHODS

This systematic review and meta-analysis will be performed according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Two reviewers independently will search randomized controlled trials or observational studies about the treatment of nicorandil on AMI patients. Retrieved databases include Web of Science, ClinicalTrials.gov, Pubmed, Embase, and Cochrane Library. And retrieval time is limited from inception to June 2021. Key words are nicorandil, myocardial infarction, or similar expansion words without publication limitation. Biomechanical studies, in vitro studies, review articles, techniques, case reports, letters to the editor, and editorials are excluded.

RESULTS

The results of our review will be reported strictly following the PRISMA criteria and the review will add to the existing literature by showing compelling evidence and improved guidance in clinic settings.

OSF REGISTRATION NUMBER

10.17605/OSF.IO/UEPKB.

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.

Mitochondrial dysfunction in cardiovascular disease: Current status of translational research/clinical and therapeutic implications

Mitochondria provide energy to the cell during aerobic respiration by supplying ~95% of the adenosine triphosphate (ATP) molecules via oxidative phosphorylation. These organelles have various other functions, all carried out by numerous proteins, with the majority of them being encoded by nuclear DNA (nDNA). Mitochondria occupy ~1/3 of the volume of myocardial cells in adults, and function at levels of high-efficiency to promptly meet the energy requirements of the myocardial contractile units. Mitochondria have their own DNA (mtDNA), which contains 37 genes and is maternally inherited. Over the last several years, a variety of functions of these organelles have been discovered and this has led to a growing interest in their involvement in various diseases, including cardiovascular (CV) diseases. Mitochondrial dysfunction relates to the status where mitochondria cannot meet the demands of a cell for ATP and there is an enhanced formation of reactive-oxygen species. This dysfunction may occur as a result of mtDNA and/or nDNA mutations, but also as a response to aging and various disease and environmental stresses, leading to the development of cardiomyopathies and other CV diseases. Designing mitochondria-targeted therapeutic strategies aiming to maintain or restore mitochondrial function has been a great challenge as a result of variable responses according to the etiology of the disorder. There have been several preclinical data on such therapies, but clinical studies are scarce. A major challenge relates to the techniques needed to eclectically deliver the therapeutic agents to cardiac tissues and to damaged mitochondria for successful clinical outcomes. All these issues and progress made over the last several years are herein reviewed.

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

The Effect of Pharmacological Preconditioning with Nicorandil before Elective Coronary Stenting on the Long-Term Prognosis of Patients with Stable Coronary Artery Disease

Aim. To study nicorandil prescription effects before elective percutaneous coronary intervention (PCI) to prevent myocardial injury and 4a type acute myocardial infarction (MI, primary endpoint) and cardiovascular events (CVE) in the first year after PCI (secondary endpoint) in patients with stable coronary artery disease.

Material and methods. 182 patients with stable coronary artery disease were included into the study and were randomized into two groups: nicorandil treatment group (n=90) and a control group with a standard medical treatment (n=92). Nicorandil was prescribed orally: 2 days before PCI – 30 mg/day; on the day of PCI – 20 mg 2 hours before intervention and 10 mg 6-12 hours after PCI; over the next 30 days – 30 mg/day. High sensitivity troponin I (hs-Tr) and creatine kinase-MB tests were carried out before PCI, 24 and 72 hours after the intervention; the 4a type MI was diagnosed according to the 4th Universal Definition. Non-fatal myocardial infarction, nonfatal stroke, death from cardiovascular diseases, repeat revascularization (PCI, coronary artery bypass surgery due to aggravation), hospital admissions for angina pectoris recurrence (without interventions) and death from any causes were considered as cardiovascular events. Data on adverse outcomes were collected over the hospital stay, and then 30, 180 and 365 days after the hospital discharge.

Results. 4a type MI was diagnosed in 14 patients (8%), in women – 12% and in men – 6%. There was a significant decrease in the incidence of type 4a MI in the nicorandil group (n=3; 3%) compared with the control group (n=11; 12%; p=0.05). Secondary endpoint was recorded in 21% of patients. The relationship was found between 4a type MI and the incidence of CVE the next year after the PCI (p=0.01). In patients with type 4a MI CVE odd ratio increases 5.8 times with confidence interval from 1.5426 to 21.6024. According to the logistic regression analysis the significant relationship between hs-Tr growth 24 hours after the PCI and CVE incidence next year after the PCI was found with cutting value 389.8 pg/ml, AUC=0.641 (p=0.04).

Сonclusion. Peroral nicorandil 30 mg/day 2 days before PCI, 20 mg 2 hours before surgery and 10 mg 6-12 hours after PCI, and 30 mg/day next 30 days after PCI decreases the risk of intraoperative myocardial injury and CVE in the next year after PCI.

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.

Effects of nicorandil infusion on ECG parameters in patients with unstable angina pectoris and percutaneous coronary intervention

Background

Percutaneous coronary intervention (PCI) is effective in treating patients with acute coronary syndrome (ACS) but is associated with some serious complications. Nicorandil is an anti‐anginal agent acting to improve microvascular circulation and to increase coronary blood flow. The objective of this article is to evaluate the effects of intracoronary injection followed with continuous intravenous injection of nicorandil on ECG parameters in patients with unstable angina pectoris (UA) undergoing PCI.

Methods

A single‐center, self‐controlled clinical trial was conducted at the Second Hospital of Tianjin Medical University between January 2019 and April 2019. Sixty‐three consecutive patients with UA who received coronary angiography and selective PCI were enrolled. ECG was recorded and analyzed before and 24 hr after nicorandil infusion.

Results

Patients were divided into three groups: control group (n = 23, aged 63.43 ± 12.55 years), short‐term, and prolonged use with nicorandil group (n = 20 and 20, aged 66.45 ± 8.06 years and 65.80 ± 9.49 years, respectively). Clinical characteristics and ECG parameters were similar before PCI among three groups (p > .05). In nicorandil treatment groups, intervals of QTd and Tp‐e in patients post‐PCI were significantly shorter than that in control and pre‐PCI (p < .05).

Conclusions

Nicorandil infusion reduces QTd and Tp‐e interval in patients with UA. Further studies will be needed to determine whether these electrophysiological changes are associated with a reduction of ventricular arrhythmias and improved outcomes.

Targeting mitochondria for cardiovascular disorders: therapeutic potential and obstacles

A large body of evidence indicates that mitochondrial dysfunction has a major role in the pathogenesis of multiple cardiovascular disorders. Over the past 2 decades, extraordinary efforts have been focused on the development of agents that specifically target mitochondria for the treatment of cardiovascular disease. Despite such an intensive wave of investigation, no drugs specifically conceived to modulate mitochondrial functions are currently available for the clinical management of cardiovascular disease. In this Review, we discuss the therapeutic potential of targeting mitochondria in patients with cardiovascular disease, examine the obstacles that have restrained the development of mitochondria-targeting agents thus far, and identify strategies that might empower the full clinical potential of this approach.

Nicorandil prior to primary percutaneous coronary intervention improves clinical outcomes in patients with acute myocardial infarction: a meta-analysis of randomized controlled trials

Background: Nicorandil prior to reperfusion by primary percutaneous coronary intervention (PCI) in patients with ST-segment elevated myocardial infarction (STEMI) has been suggested to be beneficial. However, results of previous randomized controlled trials (RCTs) were not consistent. We aimed to perform a meta-analysis to systematically evaluate the effect of periprocedural nicorandil in these patients. Methods: Related studies were obtained by searching PubMed, Embase and Cochrane's Library. Effects of perioperative nicorandil on the incidence of no-reflow phenomenon (NRP), corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC), wall motion score (WMS), left ventricular ejection fraction (LVEF), heart failure (HF) exacerbation of rehospitalization and incidence of major cardiovascular adverse events (MACE) were analyzed. Results: Eighteen RCTs with 2,055 patients were included. Treatment of nicorandil prior to PCI significantly reduced the incidence of NRP (risk ratio [RR]: 0.47, P<0.001), and reduced CTFC (weighed mean difference [WMD]: -4.54, P<0.001) immediately after PCI. Moreover, although nicorandil did not significantly affect WMS (WMD: 0.04, P=0.91), treatment of nicorandil significantly increased LVEF in STEMI patients undergoing primary PCI (WMD: 1.89%, P<0.001). In addition, nicorandil significantly reduced the risk of HF exacerbation or rehospitalization (RR: 0.44, P=0.001) and the incidence of MACE (RR: 0.68, P<0.001). Further analyses showed that effects of nicorandil on LVEF, HF exacerbation and MACE were consistent within one month after PCI and during follow-up. Conclusions: Periprocedural nicorandil improves coronary blood flow, cardiac systolic function and prognosis in STEMI patients receiving primary PCI.

Effect of sequential nicorandil on myocardial microcirculation and short-term prognosis in acute myocardial infarction patients undergoing coronary intervention

Background

This study aims to observe the effects of the intracoronary and peripheral venous administration of nicorandil for the postoperative myocardial microcirculation and short-term prognosis of ST-segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI) treatment.

Methods

A total of 140 STEMI patients were divided into three groups according to different patterns of administration: sequential nicorandil group, intracoronary nicorandil group and control group. The main observation indexes included coronary blood flow and myocardial perfusion immediately after PPCI, while the secondary observation indexes included major adverse cardiovascular events (MACE) and left ventricular ejection fraction (LVEF) during the period of hospitalization.

Results

After PPCI, the difference in the proportion of patients with thrombolysis in myocardial infarction (TIMI) flow grade 3 among the three groups was statistically significant (P=0.036), where this proportion was higher in the sequential nicorandil group and intracoronary nicorandil group than in the control group (P=0.022 and P=0.047); The difference in corrected TIMI frame count (CTFC) among the three groups was statistically significant (P=0.022), where CTFC was lower in the sequential nicorandil group and intracoronary nicorandil group than in the control group (P=0.010, P=0.031); The differences in the proportion of patients with complete ST resolution (STR) and advancing of enzyme peak time to within 12 h between each two groups were statistically significant (P<0.001), where this proportion was the highest in the sequential nicorandil group; The difference in the CK-MB peak among the three groups was statistically significant (P=0.036), where the CK-MB peak was lower in the sequential nicorandil group than in the control group (P=0.012); The difference in the incidence of MACE between each two groups was statistically significant (P<0.001), where this incidence was the lowest in the sequential nicorandil group; The differences in the proportion of patients with advancing of enzyme peak time to within 14 h and LVEF among the three groups were not statistically significant (P=0.722 and P=0.284).

Conclusions

Compared with intracoronary use alone, the intracoronary and peripheral intravenous use of nicorandil can better improve myocardial microcirculation and short-term prognosis.

Intracoronary administration of nicorandil-induced cardiac arrest during primary percutaneous coronary intervention: A case report

RATIONALE

Primary percutaneous coronary intervention (PPCI) is the most effective therapy for patients with an acute ST-segment elevation myocardial infarction (STEMI). However, up to half of STEMI patients suffer from coronary microvascular dysfunction, presenting as the slow flow or no-reflow phenomenon.

PATIENTS CONCERNS

A 78-year-old man was admitted to the chest pain center with sudden chest pain and tightness for about an hour.

DIAGNOSES

Electrocardiography demonstrated ST-segment elevation in leads II, III, aVF, and third-degree atrioventricular block. Coronary angiography showed acute total occlusion in the distal right coronary artery (RCA).

INTERVENTIONS

PPCI was performed on the patient. After thrombus aspiration, a stent was placed in the distal RCA. As coronary angiography showed TIMI grade 2 flow in RCA, 6 mg nicorandil was intracoronary administrated in twice. Immediately, cardiac arrest occurred and cardiopulmonary resuscitation (CPR) was performed.

OUTCOMES

The patient survived and had a good outcome during follow-up for >6 months.

LESSONS

Up to now, there has been no case report of cardiac arrest caused by nicorandil. Although intracoronary nicorandil is one of the most commonly used methods to improve coronary flow, much more attention should be paid to side effects of nicorandil.

Effect of nicorandil administration on myocardial microcirculation during primary percutaneous coronary intervention in patients with acute myocardial infarction

Introduction

Prevention of the no-reflow phenomenon has a crucial role in primary percutaneous coronary intervention (P-PCI) procedures.

Aim

To assess the effects of early intracoronary administration of nicorandil (NIC) during P-PCI on myocardial microcirculation in patients with acute myocardial infarction (AMI).

Material and methods

A total of 120 patients with first acute anterior wall ST segment elevation myocardial infarction who underwent P-PCI were randomly divided into two groups: the NIC group (A, n = 60) and the placebo group (B, n = 60). Before stent placement, NIC or normal saline was injected using a guiding catheter. The thrombolysis in myocardial infarction (TIMI) grade, TIMI myocardial perfusion grade (TMPG), resolution of ST segment elevation (defined as > 50% decrease in ST elevation) 1 h after surgery, and ⁹⁹Tc^m-methoxyisobutyl isocyanide (MIBI) rest myocardial perfusion imaging (MPI) via single-photon emission computed tomography (⁹⁹Tc^m-MIBI SPECT) findings 10 days after surgery were compared between the two groups.

Results

The number of patients who achieved TIMI grade 3 (96.67% vs. 86.67%; p = 0.047) and TMPG 3 (95% vs. 83.33%; p = 0.040) was higher in the NIC group than in the placebo group. Resolution of ST segment elevation occurred in 95% and 81.67% of the patients in the NIC and placebo groups, respectively (p = 0.023); the MPI score of the two groups was 4.1 ±1.89 and 7.3 ±2.65, respectively (p = 0.014).

Conclusions

Early coronary administration of NIC can significantly reduce the damage in the myocardial microcirculation caused by P-PCI and the myocardial infarct size in patients with AMI.

Effect of intracoronary agents on the no-reflow phenomenon during primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction: a network meta-analysis

Background

Despite the restoration of epicardial flow after primary percutaneous coronary intervention (PPCI), myocardial reperfusion remains impaired in a significant proportion of patients. We performed a network meta-analysis to assess the effect of 7 intracoronary agents (adenosine, anisodamine, diltiazem, nicorandil, nitroprusside, urapidil, and verapamil) on the no-reflow phenomenon in patients with ST-elevation myocardial infarction (STEMI) undergoing PPCI.

Methods

Database searches were conducted to identify randomized controlled trials (RCTs) comparing the 7 agents with each other or with standard PPCI. Outcome measures included thrombolysis in myocardial infarction flow grade (TFG), ST-segment resolution (STR), left ventricular ejection fraction (LVEF), major adverse cardiovascular events (MACEs), and adverse events.

Results

Forty-one RCTs involving 4069 patients were analyzed. The addition of anisodamine to standard PPCI for STEMI was associated with improved post-procedural TFG, more occurrences of STR, and improvement of LVEF. The cardioprotective effect of anisodamine conferred a MACE-free survival benefit. Additionally, nitroprusside was regarded as efficient in improving coronary flow and clinical outcomes. Compared with standard care, adenosine, nicorandil, and verapamil improved coronary flow but had no corresponding benefits regarding cardiac function and clinical outcomes. The ranking probability for the 7 treatment drugs showed that anisodamine consistently ranked the highest in efficacy outcomes (TFG < 3, STR, LVEF, and MACEs). No severe adverse events, such as hypotension and malignant arrhythmia, were observed in patients treated with anisodamine. Network meta-regression analysis showed that age, the time to reperfusion, and study follow-up did not affect the treatment effects.

Conclusions

The intracoronary administration of anisodamine appears to improve myocardial reperfusion, cardiac function, and clinical outcomes in patients with STEMI undergoing PPCI. Given the limited quality and quantity of the included studies, more rigorous RCTs are needed to verify the role of this inexpensive and well-tolerated regimen.

Electronic supplementary material

The online version of this article (10.1186/s12872-017-0722-z) contains supplementary material, which is available to authorized users.

Data on administration of cyclosporine, nicorandil, metoprolol on reperfusion related outcomes in ST-segment Elevation Myocardial Infarction treated with percutaneous coronary intervention

Mortality and morbidity in patients with ST elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI) are still high [1]. A huge amount of the myocardial damage is related to the mitochondrial events happening during reperfusion [2]. Several drugs directly and indirectly targeting mitochondria have been administered at the time of the PCI and their effect on fatal (all-cause mortality, cardiovascular (CV) death) and non fatal (hospital readmission for heart failure (HF)) outcomes have been tested showing conflicting results [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16]. Data from 15 trials have been pooled with the aim to analyze the effect of drug administration versus placebo on outcome [17]. Subgroup analysis are here analyzed: considering only randomized clinical trial (RCT) on cyclosporine or nicorandil [3], [4], [5], [9], [10], [11], excluding a trial on metoprolol [12] and comparing trial with follow-up length <12 months versus those with longer follow-up [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15], [16]. This article describes data related article titled “Clinical Benefit of Drugs Targeting Mitochondrial Function as an Adjunct to Reperfusion in ST-segment Elevation Myocardial Infarction: a Meta-Analysis of Randomized Clinical Trials” [17].

Early Administration of Intracoronary Nitroprusside Compared with Thrombus Aspiration in Myocardial Perfusion for Acute Myocardial Infarction: A 3-Year Clinical Follow-Up Study

BACKGROUND

Intracoronary nitroprusside and thrombus aspiration have been demonstrated to improve myocardial perfusion during percutaneous coronary interventions (PCI) for ST-segment elevation acute myocardial infarction (STEMI) However, no long-term clinical studies have been performed comparing these approaches.

METHODS

A single medical center retrospective study was conducted to evaluate the effects of intracoronary nitroprusside administration before slow/no-reflow phenomena versus thrombus aspiration during primary PCI. Forty-three consecutive patients with STEMI were enrolled in the intracoronary nitroprusside treatment group. One hundred twenty-four consecutive STEMI patients who received thrombus aspiration were enrolled; ninety-seven consecutive STEMI patients who did not receive either thrombus aspiration or intracoronary nitroprusside treatment were enrolled and served as control subjects. Patients with cardiogenic shock, who had received platelet glycoprotein IIb/IIIa inhibitor, or intra-aortic balloon pump insertion were excluded. Thrombolysis in Myocardial Infarction (TIMI) flow grade, corrected TIMI frame count and TIMI myocardial perfusion grade (TMPG) were assessed prior to and following PCI by two independent cardiologists blinded to the procedures. The rate of major adverse cardiac events (MACE) at 30 days, 1 year, and 3 years after study enrollment as a composite of recurrent myocardial infarction, target-vessel revascularization, and cardiac death were recorded.

RESULTS

The control group had a significantly lower pre-PCI TIMI flow (≤ 1; 49.5% vs. 69.8% vs. 77.4%; p = < 0.001) compared with the nitroprusside and thrombus aspiration groups. The thrombus aspiration group had a significantly higher pre-PCI thrombus score (> 4; 98.4% vs. 88.4% vs. 74.3%; p = < 0.001) and post-PCI TMPG (3; 39.5% vs. 16.3% vs. 20.6%; p = 0.001) compared with the nitroprusside and control groups. No significant differences were noted in the post-PCI thrombus score, 30-day, 1-year and 3-year MACE rate, and Kaplan-Meier curve among 3 groups of patients.

CONCLUSIONS

Although thrombus aspiration provided improved TMPG compared with early administration of intracoronary nitroprusside and neither of both during primary PCI, it did not have a significant impact on 30-day, 1-year and 3-year MACE rate.

KEY WORDS

Acute myocardial infarction; Intracoronary nitroprusside; Thrombus aspiration.

Ischemia reperfusion injury as a modifiable therapeutic target for cardioprotection or neuroprotection in patients undergoing cardiopulmonary resuscitation

AIMS

We sought to review cellular changes that occur with reperfusion to try to understand whether ischemia-reperfusion injury (RI) is a potentially modifiable therapeutic target for cardioprotection or neuroprotection in patients undergoing cardiopulmonary resuscitation.

DATA SOURCES

Articles written in English and published in PubMed.

RESULTS

Remote ischemic conditioning (RIC) involves brief episodes of non-lethal ischemia and reperfusion applied to an organ or limb distal to the heart and brain. Induction of hypothermia involves cooling an ischemic organ or body. Both have pluripotent effects that reduce the potential harm associated with RI in the heart and brain by reduced opening of the mitochondrial permeability transition pore. Recent trials of RIC and induced hypothermia did not demonstrate these treatments to be effective. Assessment of the effect of these interventions in humans to date may have been modified by use of concurrent medications including propofol.

CONCLUSIONS

Ongoing research is necessary to assess whether reduction of RI improves patient outcomes.

Usefulness and safety of intracoronary administration of nicorandil for evaluating fractional flow reserve in Japanese patients

BACKGROUND

Fractional flow reserve (FFR) is useful for determining the functional significance of epicardial coronary stenosis and may facilitate clinical decision making in patients with an equivocal coronary stenosis for coronary revascularization. Therefore, determining an efficient and safe method to achieve hyperemia is important for evaluating FFR. We investigated the usefulness and safety of intracoronary bolus administration of nicorandil compared with intravenous administration of adenosine triphosphate (ATP) for evaluating FFR in Japanese patients with suspected angina pectoris.

METHODS

First, we evaluated the most appropriate hyperemic dose of nicorandil in the first 11 consecutive patients out of 101 Japanese patients. Next, we compared the FFR induced by ATP and by 2 mg of nicorandil in 130 vessels of the 101 patients.

RESULTS

FFR was measured according to nicorandil dose in 14 vessels among 11 of the 101 patients; 92.9% of the patients achieved hyperemia with 2 mg of nicorandil. The FFR values obtained with ATP were significantly correlated with those obtained with 2 mg of nicorandil (regression coefficient = 0.974, R(2) = 0.933, P < 0.001). There were no hypotension cases needing a vasopressor after ATP or nicorandil administration, and there was 1 case of transient second-degree atrioventricular block after ATP administration. The time taken to achieve hyperemia after nicorandil administration (18.9 ± 9.6 seconds) was significantly shorter than that after ATP administration (197.9 ± 23.8 seconds) (P < 0.001).

CONCLUSIONS

Intracoronary nicorandil administration is more useful than and as safe as intravenous administration of ATP for evaluating FFR in Japanese patients.

Intracoronary administration of anisodamine and nicorandil in individuals undergoing primary percutaneous coronary intervention for acute inferior myocardial infarction: A randomized factorial trial

In acute inferior myocardial infarction (AIMI), numerous conventional drugs that are used to improve the myocardial microcirculation can significantly reduce blood pressure (BP) and coronary perfusion pressure, aggravate bradyarrhythmia and cause a deterioration in the hemodynamic state of the whole body, which greatly limits the application of these drugs in clinical settings. The aim of the present study was to assess the effect of anisodamine and nicorandil regimens on the prevention of no-reflow (NR) and the amelioration of myocardial reperfusion in patients with AIMI undergoing primary percutaneous coronary intervention (PCI). A total of 104 consecutive patients with AIMI were included in this study and randomly assigned to one of four groups: A (control group), B (anisodamine group), C (nicorandil group) and D (anisodamine and nicorandil group). Patients underwent PCI via transradial artery access and the angiographic results were evaluated. Coronary diastolic BP (DBP) and systolic and mean BPs were measured by invasive catheterization. The primary end-point was a post-PCI Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade (TMPG) of 3. Composite end-points (mortality + new MI + target vessel revascularization) were evaluated during the hospital stay and 30 days after discharge. Following the procedure, the proportion of patients achieving TMPG 3 was significantly higher in group D than that in the other groups (P=0.014); furthermore, the incidence of a postprocedural TIMI score of 3 was the highest in group D. Three days after the procedure, the peak creatine kinase-MB and cardiac troponin I levels were the lowest and the left ventricular ejection fraction was the highest in group D. A thrombus score of 3/4 and low DBP were the independent risk factors for poor myocardial reperfusion (expressed as TMPG <3), while 2 mg anisodamine plus 2 mg nicorandil prior to PCI was protective for optimal myocardial reperfusion following the procedure. The combination of anisodamine and nicorandil can effectively ameliorate myocardial reperfusion and protect cardiac function in patients with AIMI undergoing primary PCI.

Nicorandil prevents microvascular dysfunction resulting from PCI in patients with stable angina pectoris: a randomised study

AIMS

Nicorandil, an ATP sensitive potassium channel opener, may reduce the incidence of microvascular dysfunction after percutaneous coronary intervention (PCI) by dilating coronary resistance vessels. The aim of the study was evaluation of the impact of the administration of intravenous nicorandil on measuring the index of microcirculatory resistance (IMR) in PCI to patients with stable angina pectoris (SAP).

METHODS AND RESULTS

Intravascular ultrasound (IVUS), fractional flow reserve (FFR), IMR and blood examination (CK-MB), cardiac troponin I (cTnI) immediately post-PCI (and 24 hours later) were performed in 62 consecutive patients with SAP undergoing PCI. FFR and IMR were measured simultaneously with a single coronary pressure wire. IMR was defined as Pd/coronary flow (or Pd* mean transit time) at peak hyperaemia. Patients were randomised to the control (n=29), or nicorandil group (n=33). In the nicorandil group, nicorandil was intravenously administered as a 6 mg bolus injection just before PCI and as a constant infusion at 6 mg/hour for 24 hours thereafter. All volumetric IVUS parameters and FFR were similar between the two groups both pre- and post-PCI. However, IMR immediately post-PCI and cTnI 24 hours post-PCI were significantly higher in the control group compared to the nicorandil group (IMR: 25.4±12.1 vs. 17.9±9.1 units, and cTnI: 0.21±0.13 vs. 0.12±0.08 ng/mL, for control vs. nicorandil). The incidence for cTnI elevation more than fivefold the normal range (>0.20 ng/mL) was significantly larger in the control group than in the nicorandil group (41% vs. 12%, p<0.01). Additionally, the control group showed a closer correlation between plaque volume reduction during stenting as assessed by volumetric IVUS, and cTnI elevation than the nicorandil group (r=0.55 vs. 0.42, p<0.001 for control vs. nicorandil).

CONCLUSIONS

In patients undergoing successful coronary stenting for stable angina, administration of nicorandil is associated with reduced microvascular dysfunction induced by PCI.

All-cause mortality and cardiovascular events with nicorandil in patients with IHD: systematic review and meta-analysis of the literature

BACKGROUND

Nicorandil is able to protect the cardiomyocytes from ischemic damage, but clear benefits of nicorandil in all-cause mortality and cardiovascular events were not consistently reported in patients with ischemic heart disease (IHD).

MATERIALS AND RESULTS

Cochrane, PubMed, EMBASE, CBM, CNKI and Wangfang databases were searched for randomized controlled trials. Data on all-cause mortality and cardiovascular events were collected. Nicorandil groups were pooled to perform a comparison with control groups and to get the pooled odds ratios (ORs) and associated 95% confidence intervals (CIs) for all-cause mortality, relative risks (RRs), and associated 95% CIs for cardiovascular events. STATA 11.0 software was used for all-cause mortality and cardiovascular events statistics. We retrieved 17 randomized controlled studies enrolling a total of 7305 patients. The addition of nicorandil treatment significantly reduced cardiovascular events (13.83% versus 18.01%; RR, 0.77; 95% CI, 0.69 to 0.86). No differences in all-cause mortality (3.83% versus 4.70%; OR, 0.81; 95% CI, 0.64 to 1.02), and repeat revascularization rate (13.06% versus 13.54%; RR, 0.95; 95% CI, 0.70 to 1.29) were observed. There was a weak linear association between cardiovascular events and nicorandil in IHD with diabetes (P=0.099).

CONCLUSIONS

The results suggest that nicorandil as an adjunct therapy to IHD is associated with reduced cardiovascular events in patients with IHD.

Nicorandil in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention: a systematic review and meta-analysis

Background

Nicorandil, as an adjunctive therapy with primary percutaneous coronary intervention (PCI), had controversial benefits in cardioprotection in patients with acute myocardial infarction (AMI).

Methods and Results

We performed a systematic review of randomized controlled trials (RCTs) comparing treatment with nicorandil prior to reperfusion therapy with control (placebo or no nicorandil) in patients who suffered from AMI and performed primary PCI. PubMed, EMBASE and CENTRAL databases and other sources were searched without language and publication restriction. 14 trials involving 1680 patients were included into this meta-analysis. Nicorandil significantly reduced the incidence of thrombolysis in myocardial infarction (TIMI) flow grade ≤2 (risk ratio [RR], 0.57; 95% confidence interval [CI]: 0.42 to 0.79), the Timi frame count (TFC) (mean difference [MD], -5.19; 95% CI: -7.13 to -3.26), increased left ventricular ejection fraction (LVEF) (%) (MD, 3.08; 95% CI: 0.79 to 5.36), and reduced the incidence of ventricular arrhythmia (RR, 0.53; 95% CI: 0.37 to 0.76) and congestive heart failure (CHF) (RR, 0.41; 95% CI: 0.22 to 0.75). No difference in the pear creatine kinase (CK) value (MD, -290.19; 95% CI: -793.75 to 213.36) or cardiac death (RR, 0.39; 95% CI: 0.09 to 1.67) was observed.

Conclusions

Nicorandil prior to reperfusion is associated with improvement of coronary reflow as well as suppression of ventricular arrhythmia, and further improves left ventricular function in patients who suffered from AMI and underwent primary PCI. But the definite clinical benefits of nicorandil were not found, which may be due to the small sample size of the selected studies.

Targeting reperfusion injury in acute myocardial infarction: a review of reperfusion injury pharmacotherapy

INTRODUCTION

Acute myocardial infarction (AMI) (secondary to lethal ischemia-reperfusion [IR]) contributes to much of the mortality and morbidity from ischemic heart disease. Currently, the treatment for AMI is early reperfusion; however, this itself contributes to the final myocardial infarct size, in the form of what has been termed 'lethal reperfusion injury'. Over the last few decades, the discovery of the phenomena of ischemic preconditioning and postconditioning, as well as remote preconditioning and remote postconditioning, along with significant advances in our understanding of the cardioprotective pathways underlying these phenomena, have provided the possibility of successful mechanical and pharmacological interventions against reperfusion injury.

AREAS COVERED

This review summarizes the evidence from clinical trials evaluating pharmacological agents as adjuncts to standard reperfusion therapy for ST-elevation AMI.

EXPERT OPINION

Reperfusion injury pharmacotherapy has moved from bench to bedside, with clinical evaluation and ongoing clinical trials providing us with valuable insights into the shortcomings of current research in establishing successful treatments for reducing reperfusion injury. There is a need to address some key issues that may be leading to lack of translation of cardioprotection seen in basic models to the clinical setting. These issues are discussed in the Expert opinion section.

Relationship between retrograde coronary blood flow and the extent of no-reflow and infarct size in a porcine ischemia-reperfusion model

Recanalization of an infarct-related artery does not predictably reflect tissue reperfusion. We examined the relationship between coronary blood flow (CBF) pattern during reperfusion and infarcted (IA) and no-reflow (NR) area in a porcine ischemia-reperfusion model. The mid-left anterior descending artery of 18 pigs was occluded for 1 h and reperfused for 2 h. CBF during reperfusion was measured with a transit-time ultrasound flowmeter, while systemic arterial and left atrial pressures were monitored. IA and NR were measured with triphenyl tetrazolium chloride and thioflavin staining, respectively. In 13 pigs, early systolic retrograde CBF developed within the first 30 min and persisted throughout reperfusion. No retrograde CBF was observed in five pigs. Mean retrograde CBF at 2 h of reperfusion predicted a larger IA (r = 0.71; p = 0.001). Time-to-development of retrograde CBF was inversely related to IA (r = -0.55; p = 0.019) and NR (r = -0.62; p = 0.006). A larger IA (OR 1.12, 95% CI 1.01-1.24, p = 0.037) and NR (OR 1.09, 95% CI 1.01-1.18, p = 0.037) predicted the presence of retrograde CBF. Retrograde CBF during recanalization of the infarct-related artery predicts IA and NR and might be used as an index of successful reperfusion at the tissue level.

Diannexin reduces no-reflow after reperfusion in rabbits with large ischemic myocardial risk zones

INTRODUCTION AND AIMS

In patients with ST-segment elevation myocardial infarction who receive percutaneous coronary intervention and stenting, a large zone with no-reflow is associated with adverse outcomes. During myocardial ischemia/reperfusion, phosphatidylserine (PS) translocates to the surface of endothelial cells triggering attachment of platelets and leukocytes, thus impairing microvascular blood flow. Diannexin, a recombinant dimer of the endogenous human annexin V protein, binds PS and thus inhibits the adverse effects of PS. It has been shown to attenuate postischemic reperfusion injury in several experimental models. We speculated that Diannexin would reduce no-reflow in the heart after coronary artery occlusion (CAO) and reperfusion. Rabbits received: (1) Diannexin 5 min pre-CAO (diannexin pre ischemia [DPI], 400 μg/kg, n = 17), or (2) Diannexin 5 min pre-coronary reperfusion (diannexin pre reperfusion [DPR], 400 μg/kg, n = 20), or (3) saline (Cont, n = 18), with 30 min CAO and 3 h reperfusion. In a secondary analysis, rabbits were divided into two groups based on the overall average risk zone size of 29% of the left ventricle (LV): small (<29% of LV) and large (>29% of LV).

RESULTS

Overall, risk zones and infarct size, and the no-reflow zone were similar in all groups. In hearts with large risk zones the no-reflow area was significantly smaller in both drug-treated groups (DPI, 22 ± 5% and DPR, 22 ± 3% vs. control 40 ± 3%, P < 0.006), the hemorrhagic areas were significantly smaller, and infarct size was reduced at the P < 0.06 level compared with control. In animals with small risk zones there were no significant differences. Diannexin treatment did not affect hemodynamics or LV function.

CONCLUSION

Diannexin was cardioprotective in rabbits with a severe ischemic insult. This is important, because large infarcts accompanied by no-reflow in humans are associated with increased complications. In animals with small risk zones, no significant drug effect was observed.

High index of microcirculatory resistance level after successful primary percutaneous coronary intervention can be improved by intracoronary administration of nicorandil

BACKGROUND

Although microvascular dysfunction following percutaneous coronary intervention (PCI) can be evaluated with the index of microcirculatory resistance (IMR), no method of treatment has been established. We hypothesized that intracoronary administration of nicorandil can improve IMR after successful primary PCI in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

In 40 patients with first STEMI after successful primary PCI, IMR was measured using PressureWire(TM) Certus (St. Jude Medical, MN, USA). In 20 of the patients (Group N), IMR was measured at baseline and after intracoronary nicorandil (2 mg/10 ml). In the other 20 patients (Control), IMR was measured at baseline, after intracoronary saline (10 ml) and after intracoronary nicorandil (2 mg/10 ml). In Group N, IMR significantly decreased after intracoronary nicorandil (median IMR, 27.7-18.7 U, P<0.0001). In the Control group, IMR did not change after saline administration (median IMR, 24.3-23.8 U, P=0.8193), but was significantly decreased after intracoronary nicorandil (median IMR, 23.8-14.9 U, P<0.0001). Next, all 40 patients were divided into subgroups by tertile of baseline IMR. In those with intermediate to high IMR (baseline IMR > or =21), intracoronary nicorandil significantly decreased IMR, although it did not change IMR in those with low IMR (baseline IMR <21).

CONCLUSIONS

High IMR levels in patients with STEMI after successful primary PCI can be improved by intracoronary administration of nicorandil.