Vasodilator Therapy: Nitrates and Nicorandil

In Vivo Mapping of Myocardial Injury Outside the Infarct Zone: Tissue at an Intermediate Pathological State

BACKGROUND

The goal was to determine the feasibility of mapping the injured-but-not-infarcted myocardium using 99mTc-duramycin in the postischemic heart, with spatial information for its characterization as a pathophysiologically intermediate tissue, which is neither normal nor infarcted.

METHODS AND RESULTS

Coronary occlusion was conducted in Sprague Dawley rats with preconditioning and 30-minute ligation. In vivo single-photon emission computed tomography was acquired after 3 hours (n=6) using 99mTc-duramycin, a phosphatidylethanolamine-specific radiopharmaceutical. The 99mTc-duramycin+ areas were compared with infarct and area-at-risk (n=8). Cardiomyocytes and endothelial cells were isolated for gene expression profiling. Cardiac function was measured with echocardiography (n=6) at 4 weeks. In vivo imaging with 99mTc-duramycin identified the infarct (3.9±2.4% of the left ventricle and an extensive area 23.7±2.2% of the left ventricle) with diffuse signal outside the infarct, which is pathologically between normal and infarcted (apoptosis 1.8±1.6, 8.9±4.2, 13.6±3.8%; VCAM-1 [vascular cell adhesion molecule 1] 3.2±0.8, 9.8±4.1, 15.9±4.2/mm2; tyrosine hydroxylase 14.9±2.8, 8.6±4.4, 5.6±2.2/mm2), with heterogeneous changes including scattered micronecrosis, wavy myofibrils, hydropic change, and glycogen accumulation. The 99mTc-duramycin+ tissue is quantitatively smaller than the area-at-risk (26.7% versus 34.4% of the left ventricle, P=0.008). Compared with infarct, gene expression in the 99mTc-duramycin+-noninfarct tissue indicated a greater prosurvival ratio (BCL2/BAX [B-cell lymphoma 2/BCL2-associated X] 7.8 versus 5.7 [cardiomyocytes], 3.7 versus 3.2 [endothelial]), and an upregulation of ion channels in electrophysiology. There was decreased contractility at 4 weeks (regional fractional shortening -8.6%, P<0.05; circumferential strain -52.9%, P<0.05).

CONCLUSIONS

The injured-but-not-infarcted tissue, being an intermediate zone between normal and infarct, is mapped in vivo using phosphatidylethanolamine-based imaging. The intermediate zone contributes significantly to cardiac dysfunction.

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.

Shedding Light on Treatment Options for Coronary Vasomotor Disorders: A Systematic Review

PURPOSE

Coronary vasomotor dysfunction embraces two specific clinical entities: coronary (micro)vascular spasm and microvascular dysfunction. The clinical manifestations of these entities are respectively called vasospastic angina (VSA) and microvascular angina (MVA). Over the years, these diseases have become more and more prominent and several studies aimed to investigate the best diagnostic and therapeutic strategies. Patients with coronary vasomotor disorders are often undertreated due to the absence of evidence-based guidelines. The purpose of this overview is to illustrate the various therapeutic options available for the optimized management of these patients.

METHODS

A Medline search of full-text articles published in English from 1980 to April 2022 was performed. The main analyzed aspects of vasomotor disorders were treatment options. We also performed research on "Clinicaltrial.gov" for ongoing trials.

CONCLUSION

Coronary (micro)vascular spasm and microvascular dysfunction are clinical entities characterized by high prevalence and clinical representation. Several therapeutic strategies, both innovative and established, are available to optimize treatment and improve the quality of life of these patients.

Ru(II) based dual nitric oxide donors: electrochemical and photochemical reactivities and vasorelaxant effect with no cytotoxicity

The synthesized complexes, cis-[Ru(NO)(NO2)(phen)2](PF6)2 (NONO2P) and cis-[Ru(NO)(NO2)(bpy)2](PF6)2 (NONO2B), were characterized by using elemental analysis, voltammetry and electronic and vibrational spectroscopy. Under electrochemical and photochemical stimulation in an aqueous medium, there are indications of the formation of complexes, which suggests that the nitro and nitrosyl groups are converted into nitric oxide. Both compounds do not show cytotoxic activity against human umbilical vein endothelial cells (HUVECs). The cis-[Ru(NO)(NO2)(phen)2](PF6)2 complex presented vasorelaxation activity in superior mesenteric arteries from Wistar rats: the biphasic concentration-response curve indicates two sites of action. In the presence of NO scavengers, we observed an impaired relaxing effect induced by NONO2P, suggesting that the vasorelaxant effect is due to NO production from this compound.

Pharmacotherapy in patients with vasomotor disorders

Background

Anginal symptoms in patients with non-obstructive coronary artery disease are frequently related to vasomotor disorders of the coronary circulation. Although frequently overlooked, a distinct diagnosis of different vasomotor disorders can be made by intracoronary function testing. Early detection and treatment seems beneficial, but little evidence is available for the medical treatment of these disorders. Nevertheless, there are several pharmacotherapeutic options available to treat these patients and improve quality of life.

Methods & findings

We performed an extensive yet non-systematic literature search to explore available pharmacotherapeutic strategies for addressing vasomotor disorders in individuals experiencing angina and non-obstructive coronary artery disease. This article presents a comprehensive overview of therapeutic possibilities for patients exhibiting abnormal vasoconstriction (such as spasm) and abnormal vasodilation (like coronary microvascular dysfunction).

Conclusion

Treatment of vasomotor disorders can be very challenging, but a general treatment algorithm based on the existing evidence and the best available current practice is feasible.

Management of Coronary Artery Disease in Older Adults: Recent Advances and Gaps in Evidence

Coronary artery disease (CAD) is highly prevalent in older adults, yet its management remains challenging. Treatment choices are made complex by the frailty burden of older patients, a high prevalence of comorbidities and body composition abnormalities (e.g., sarcopenia), the complexity of coronary anatomy, and the frequent presence of multivessel disease, as well as the coexistence of major ischemic and bleeding risk factors. Recent randomized clinical trials and epidemiological studies have provided new data on optimal management of complex patients with CAD. However, frail older adults are still underrepresented in the literature. This narrative review aims to highlight the importance of assessing frailty as an aid to guide therapeutic decision-making and tailor CAD management to the specific needs of older adults, taking into account age-related pharmacokinetic and pharmacodynamic changes, polypharmacy, and potential drug interactions. We also discuss gaps in the evidence and offer perspectives on how best in the future to optimize the global strategy of CAD management in older adults.

Coronary microvascular dysfunction and cardiovascular disease: Pathogenesis, associations and treatment strategies

Coronary microvascular dysfunction (CMD) is a high-risk factor for a variety of cardiovascular events. Due to its complex aetiology and concealability, knowledge of the pathophysiological mechanism of CMD is still limited at present, which greatly restricts its clinical diagnosis and treatment. Studies have shown that CMD is closely related to a variety of cardiovascular diseases, can aggravate the occurrence and development of cardiovascular diseases, and is closely related to a poor prognosis in patients with cardiovascular diseases. Improving coronary microvascular remodelling and increasing myocardial perfusion might be promising strategies for the treatment of cardiovascular diseases. In this paper, the pathogenesis and functional assessment of CMD are reviewed first, along with the relationship of CMD with cardiovascular diseases. Then, the latest strategies for the treatment of CMD and cardiovascular diseases are summarized. Finally, urgent scientific problems in CMD and cardiovascular diseases are highlighted and future research directions are proposed to provide prospective insights for the prevention and treatment of CMD and cardiovascular diseases in the future.

Nicorandil Exerts Anticonvulsant Effects in Pentylenetetrazol-Induced Seizures and Maximal-Electroshock-Induced Seizures by Downregulating Excitability in Hippocampal Pyramidal Neurons

N-(2-hydroxyethyl) nicotinamide nitrate (nicorandil), a nitrate that activates adenosine triphosphate (ATP)-sensitive potassium (K_ATP) channels, is generally used in the treatment of angina and offers long-term cardioprotective effects. It has been reported that several K_ATP channel openers can effectively alleviate the symptoms of seizure. The purpose of this study was to investigate the improvement in seizures induced by nicorandil. In this study, seizure tests were used to evaluate the effect of different doses of nicorandil by analysing seizure incidence, including minimal clonic seizure and generalised tonic-clonic seizure. We used a maximal electroshock seizure (MES) model, a metrazol maximal seizure (MMS) model and a chronic pentylenetetrazol (PTZ)-induced seizure model to evaluate the effect of nicorandil in improving seizures. Each mouse in the MES model was given an electric shock, while those in the nicorandil group received 0.5, 1, 2, 3 and 6 mg/kg of nicorandil by intraperitoneal injection, respectively. In the MMS model, the mice in the PTZ group and the nicorandil group were injected subcutaneously with PTZ (90 mg/kg), and the mice in the nicorandil group were injected intraperitoneally with 1, 3 and 5 mg/kg nicorandil, respectively. In the chronic PTZ-induced seizure model, the mice in the PTZ group and the nicorandil group were injected intraperitoneally with PTZ (40 mg/kg), and the mice in the nicorandil group were each given 1 and 3 mg/kg of PTZ at a volume of 200 nL. Brain slices containing the hippocampus were prepared, and cell-attached recording was used to record the spontaneous firing of pyramidal neurons in the hippocampal CA1 region. Nicorandil (i.p.) significantly increased both the maximum electroconvulsive protection rate in the MES model and the seizure latency in the MMS model. Nicorandil infused directly onto the hippocampal CA1 region via an implanted cannula relieved symptoms in chronic PTZ-induced seizures. The excitability of pyramidal neurons in the hippocampal CA1 region of the mice was significantly increased after both the acute and chronic administration of PTZ. To a certain extent, nicorandil reversed the increase in both firing frequency and proportion of burst spikes caused by PTZ (P < 0.05). Our results suggest that nicorandil functions by downregulating the excitability of pyramidal neurons in the hippocampal CA1 region of mice and is a potential candidate for the treatment of seizures.

Management of Massive Rivaroxaban Overdose With Acetaminophen and Isosorbide Mononitrate Overdose

Direct oral anticoagulants (DOACs) have been used more frequently for the prevention and management of thromboembolic disease in comparison to their predecessors. DOACs provide greater ease of administration, shorter half-lives, less monitoring, and fewer drug-drug interactions. With the rise of DOACs such as rivaroxaban, the opportunity for abuse also increases. Therefore, standardization of care based on rivaroxaban misuse must also be explored, an area in which there is not ample information. We present a case where a patient consumed a stockpile of her home medications in hopes to commit suicide. A 64-year-old female presented to the emergency department due to the ingestion of rivaroxaban 5,000 mg along with ingestion of acetaminophen 30,000 mg and isosorbide mononitrate 1000 mg in the setting of intentional self-harm with multiple declarations of being classified as Do Not Resuscitate. There have been documented cases of rivaroxaban overdose, however, there are no documented cases with levels of ingestion reaching 5,000 mg along with signs of severe bleeding. Our case study reviews the previously documented management of rivaroxaban abuse and the treatment that was given to our patient in the setting of extreme anticoagulant ingestion.

Nicorandil attenuates ventricular dysfunction and organ injury after cardiopulmonary bypass

BACKGROUND

Nicorandil, an adenosine triphosphate-sensitive potassium channel agonist and nitric oxide donor, is a coronary vasodilator used to treat ischemia-induced chest pain, but it's potential cardioprotective benefits during open heart surgery have not been thoroughly investigated. The study objective was to assess the impact of nicorandil on postoperative ventricular dysfunction and end-organ injury in an established experimental model of open-heart surgery with cardiopulmonary bypass (CPB) and cardioplegic arrest. We hypothesized that nicorandil would attenuate myocardial ischemia-reperfusion (IR) injury, preserve ventricular function, and reduce end-organ injury.

METHODS

Rabbits were cannulated for CPB, followed by 60 min of aortic cross-clamp (ACC) with cold cardioplegic arrest, and 120 min of recovery after ACC removal. Nicorandil (or normal saline vehicle) was given intravenously 5 min before ACC and continued throughout the recovery period. Left ventricular developed pressure (LVDP), systolic contractility (LV + dP/dt), and diastolic relaxation (LV -dP/dt) were continuously recorded, and blood and tissue samples were collected for measurement of oxidant stress (OS), inflammation, apoptosis, and organ injury.

RESULTS

Nicorandil significantly attenuated IR-induced LV dysfunction compared to saline control (R-120: LV + dP/dt: 1596 ± 397 vs. 514 ± 269 mmHg/s, p = 0.010; LV -dP/dt: -1524 ± 432 vs. -432 ± 243 mmHg/s, p < 0.001; LVDP: 55 ± 11 vs. 22 ± 5 mmHg, p = 0.046). Furthermore, nicorandil inhibited IR-induced increases in OS, inflammation, apoptosis, and organ injury.

CONCLUSIONS

Nicorandil exhibits myocardial protection by attenuation of IR-induced LV dysfunction associated with OS, inflammation, apoptosis, and organ injury. Nicorandil should be explored further as a potential therapeutic strategy for limiting global IR injury during open-heart surgery in humans.

Prevalence, risk factors, and survival associated with pulmonary hypertension and heart failure among patients with underlying coronary artery disease: a national prospective, multicenter registry study in China

BACKGROUND

Coronary artery disease (CAD) is the commonest cause of heart failure (HF), whereas pulmonary hypertension (PH) has not been established or reported in this patient population. Therefore, we assessed the prevalence, risk factors, and survival in CAD-associated HF (CAD-HF) complicated with PH.

METHODS

Symptomatic CAD-HF patients were continuously enrolled in this prospective, multicenter registry study. Echocardiography, coronary arteriography, left and right heart catheterization (RHC), and other baseline clinical data were recorded. Patients were followed up and their survival was recorded.

RESULTS

One hundred and eighty-two CAD-HF patients were enrolled, including 142 with HF with a preserved ejection fraction (heart failure with preserved ejection fraction [HFpEF]; left ventricular ejection fraction [LVEF] ≥50%) and 40 with a reduced ejection fraction (heart failure with reduced ejection fraction [HFrEF]; LVEF < 50%). PH was diagnosed with RHC in 77.5% of patients. Patients with PH showed worse hemodynamic parameters and higher mortality. HFrEF-PH patients had worse survival than HFpEF-PH patients. CAD-HF patients with an enlarged left ventricular end-diastolic diameter and reduced hemoglobin were at higher risk of PH. Nitrate treatment reduced the risk of PH. Elevated creatinine and mean pulmonary arterial pressure (mPAP), diastolic pressure gradient (DPG) ≥7 mmHg, and previous myocardial infarction (MI) entailed a higher risk of mortality in CAD-HF patients with PH.

CONCLUSIONS

PH is common in CAD-HF and worsens the hemodynamics and survival in these patients. Left ventricle enlargement and anemia increase the risk of PH in CAD-HF. Patients may benefit from nitrate medications. Renal impairment, elevated mPAP, DPG ≥7 mmHg, and previous MI are strong predictors of mortality in CAD-HF-PH patients.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02164526.

Best Practices in Pharmacotherapy for Acute Coronary Syndromes

Numerous advances have been made in the therapy of acute coronary syndromes. Despite these advances, acute coronary syndromes still cause significant morbidity and mortality. Decisions as to the best therapy vary depending on other patient factors, such as age, need for chronic anticoagulation, tolerability of medications, and the degree of myocardial damage. Recent evidence suggests that a shorter duration of therapy may be beneficial in decreasing bleeding events without compromising benefits of preventing ischemic complications. For those who have an indication for chronic anticoagulation, less intensive therapy may also be beneficial, again without increasing ischemic complications. Data regarding agents that inhibit the renin–angiotensin–aldosterone system are available and these data are reviewed. Knowledge of the pharmacology, potency, and pharmacokinetics of drugs, as well as adverse drug events, may direct clinicians in choosing the optimal pharmacotherapy strategy for their patients.

Nitrates vs. Other Types of Vasodilators and Clinical Outcomes in Patients with Vasospastic Angina: A Propensity Score-Matched Analysis

Although vasodilators are widely used in patients with vasospastic angina (VA), few studies have compared the long-term prognostic effects of different types of vasodilators. We investigated the long-term effects of vasodilators on clinical outcomes in VA patients according to the type of vasodilator used. Study data were obtained from a prospective multicenter registry that included patients who had symptoms suggestive of VA. Patients were classified into two groups according to use of nitrates (n = 239) or other vasodilators (n = 809) at discharge. The composite clinical events rate, including acute coronary syndrome (ACS), cardiac death, new-onset arrhythmia (including ventricular tachycardia and ventricular fibrillation), and atrioventricular block, was significantly higher in the nitrates group (5.3% vs. 2.2%, p = 0.026) during one year of follow-up. Specifically, the prevalence of ACS was significantly more frequent in the nitrates group (4.3% vs. 1.5%, p = 0.024). After propensity score matching, the adverse effects of nitrates remained. In addition, the use of nitrates at discharge was independently associated with a 2.69-fold increased risk of ACS in VA patients. In conclusion, using nitrates as a vasodilator at discharge can increase the adverse clinical outcomes in VA patients at one year of follow-up. Clinicians need to be aware of the prognostic value and consider prescribing other vasodilators.

Prognostic Power of Pulmonary Arterial Compliance Is Boosted by a Hemodynamic Unloading Test With Glyceryl Trinitrate in Heart Failure Patients With Post-capillary Pulmonary Hypertension

Background

Pulmonary hypertension (PH) is an established risk factor in patients with heart failure (HF). However, right heart catheterisation (RHC) and vasoreactivity testing (VRT) are not routinely recommended in these patients.

Methods

The primary objective of the present study was to explore the impact of VRT using sublingual glyceryl trinitrate (GTN) on transplant/ventricular assist device-free survival in HF patients with post-capillary PH. RHC parameters were correlated retrospectively with the primary outcome.

Results

The cohort comprised 154 HF patients with post-capillary PH undergoing RHC with GTN-VRT at a tertiary heart failure centre. Multiple parameters were associated with survival. After adjustment for established prognosis-relevant clinical variables from the MAGGIC Score, variables with the most relevant odds ratios (OR) obtained after GTN-VRT were: calculated effective pulmonary arterial (PA) elastance (adjusted OR 2.26, 95%CI 1.30-3.92; p = 0.004), PA compliance (PAC-GTN; adjusted OR 0.45, 95%CI 0.25-0.80; p = 0.006), and total pulmonary resistance (adjusted OR 2.29, 95%CI 1.34-3.93; p = 0.003). Forest plot analysis including these three variables as well as PAC at baseline, delta PAC, and the presence of combined post- and pre-capillary PH revealed prognostic superiority of PAC-GTN, which was confirmed by Kaplan-Meier analysis.

Conclusions

In our cohort of symptomatic HF patients with post-capillary PH, improved PAC after administration of GTN was associated with survival independent of established hemodynamic and clinical risk factors. VRT using GTN may be better described as unloading test due to GTN's complex effects on the circulation. This could be used for advanced prognostication and should be investigated in further studies.

Prognostic Impact of Chronic Vasodilator Therapy in Patients With Vasospastic Angina

Background

Chronic vasodilator therapy with long‐acting nitrate is frequently used to treat vasospastic angina. However, the clinical benefits of this approach are controversial. We investigated the prognostic impact of vasodilator therapy in patients with vasospastic angina from the multicenter, prospective VA‐KOREA (Vasospastic Angina in KOREA) registry.

Methods and Results

We analyzed data from 1895 patients with positive intracoronary ergonovine provocation test results. The patients were divided into 4 groups: no vasodilator (n=359), nonnitrate vasodilator (n=1187), conventional nitrate (n=209), and a combination of conventional nitrate and other vasodilators (n=140). The primary end point was a composite of cardiac death, acute coronary syndrome, and new‐onset arrhythmia at 2 years. Secondary end points were the individual components of the primary end point, all‐cause death, and rehospitalization due to recurrent angina.

The groups did not differ in terms of the risk of the primary end point. However, the acute coronary syndrome risk was significantly higher in the conventional nitrate (hazard ratio [HR], 2.49; 95% CI, 1.01–6.14; P=0.047) and combination groups (HR, 3.34; 95% CI, 1.15–9.75, P=0.027) compared with the no‐vasodilator group, as assessed using the inverse probability of treatment weights. Subgroup analyses revealed prominent adverse effects of nitrate in patients with an intermediate positive ergonovine provocation test result and in those with low Japanese Coronary Spasm Association scores.

Conclusions

Long‐acting nitrate‐based chronic vasodilator therapy was associated with an increased 2‐year risk of acute coronary syndrome in patients with vasospastic angina, especially in low‐risk patients.

The Anti-Inflammatory and Antiapoptotic Effects of Nicorandil in Antisepsis Cardiomyopathy

Objective

To observe the effect of nicorandil on septic rats and explore the possible mechanism of its myocardial protection, so as to provide theoretical basis for the treatment of septic cardiomyopathy.

Methods

Sixty male clean SD rats were selected as the research objects and randomly divided into 3 groups by random number method: sham operation group (sham group), cecal ligation and perforation group (CLP group), nicorandil treatment group (nicorandil+CLP group). After the operation, the nicorandil group was pumped with nicorandil diluent 1 ml/h (2 mg/kg/h) with a micropump for 6 hours. The sham group and CLP group were pumped with the same amount of normal saline 1 ml/h for a total of 6 hours. After 24 hours, the survival of the rats in each group was observed. The expression of troponin I (cTnI), tumor necrosis factor α (TNF-α), and interleukin-1β (IL-1β) in the serum was detected. Then, the ventricle was harvested for the observation of the pathological changes of myocardium. Quantitative real-time polymerase chain reaction and immunostaining were used to detect myocardial tissue apoptosis, and Western blot methods were used to detect protein expression changes in nuclear factor-κB (NF-κB) pathways.

Results

24 hours after operation, the survival rate of the rats in the CLP group was 60%. There was a large amount of necrosis of myocardial cells and inflammatory cell infiltration. The survival rate of rats in the nicorandil+CLP group was 75%. Compared with the CLP group, the necrosis of myocardial cells was reduced, and there was still a small amount of inflammatory cell infiltration. In the CLP group, myocardial inflammation and apoptosis were significant, and NF-κB pathway was activated. On the contrary, the NF-κB pathway in the nicorandil+CLP group was inhibited, and the expression of inflammatory factors and apoptosis factors was inhibited.

Conclusion

Nicorandil can reduce the release of inflammatory factors in septic rats, improve the inflammatory response, reduce myocardial damage, and play a myocardial protective effect. Its mechanism may be related to the inhibition of the activation of NF-κB signaling pathway.

Long-term and combined effects of N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide and fumaric acid on methane production, rumen fermentation, and lactation performance in dairy goats

BACKGROUND

In recent years, nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants. However, when animals receive a nitrooxy compound, a high portion of the spared hydrogen is eructated as gas, which partly offsets the energy savings of CH₄ mitigation. The objective of the present study was to evaluate the long-term and combined effects of supplementation with N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide (NPD), a methanogenesis inhibitor, and fumaric acid (FUM), a hydrogen sink, on enteric CH₄ production, rumen fermentation, bacterial populations, apparent nutrient digestibility, and lactation performance of dairy goats.

RESULTS

Twenty-four primiparous dairy goats were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments: supplementation without or with FUM (32 g/d) or NPD (0.5 g/d). All samples were collected every 3 weeks during a 12-week feeding experiment. Both FUM and NPD supplementation persistently inhibited CH₄ yield (L/kg DMI, by 18.8% and 18.1%, respectively) without negative influence on DMI or apparent nutrient digestibility. When supplemented in combination, no additive CH₄ suppression was observed. FUM showed greater responses in increasing the molar proportion of propionate when supplemented with NPD than supplemented alone (by 10.2% vs. 4.4%). The rumen microbiota structure in the animals receiving FUM was different from that of the other animals, particularly changed the structure of phylum Firmicutes. Daily milk production and serum total antioxidant capacity were improved by NPD, but the contents of milk fat and protein were decreased, probably due to the bioactivity of absorbed NPD on body metabolism.

CONCLUSIONS

Supplementing NPD and FUM in combination is a promising way to persistently inhibit CH₄ emissions with a higher rumen propionate proportion. However, the side effects of this nitrooxy compound on animals and its residues in animal products need further evaluation before it can be used as an animal feed additive.

Outpatient Management of Patients With Angina With No Obstructive Coronary Arteries: How to Come to a Proper Diagnosis and Therapy

Two-thirds of women and one-third of men who undergo a clinically indicated coronary angiography for stable angina, have no obstructive coronary artery disease (CAD). Coronary vascular dysfunction is a highly prevalent underlying cause of angina in these so called “Angina with No Obstructive Coronary Arteries (ANOCA)” patients, foremost in middle aged women. Coronary vascular dysfunction encompasses various endotypes, namely epicardial and microvascular coronary spasms, impaired vasodilatation, and increased microvascular resistance. ANOCA patients, especially those with underlying coronary vascular dysfunction, have an adverse cardiovascular prognosis, poor physical functioning, and a reduced quality of life. Since standard ischemia detection tests and coronary angiograms are not designed to diagnose coronary vascular dysfunction, this ischemic heart disease is often overlooked and hence undertreated. But adequate diagnosis is vital, so that treatment can be started to reduce symptoms, reduce healthcare costs and improve quality of life and cardiovascular prognosis. The purpose of this review is to give a contemporary overview of ANOCA with focus on coronary vascular dysfunction. We will provide a possible work-up of patients suspected of coronary vascular dysfunction in the outpatient clinical setting, based on the latest scientific insights and international consensus documents. We will discuss the value of ischemia detection testing, and non-invasive and invasive methods to diagnose coronary vascular dysfunction. Furthermore, we will go into pharmacological and non-pharmacological therapeutic options including anti-anginal regimens and lifestyle interventions.

Aging-Induced Impairment of Vascular Function: Mitochondrial Redox Contributions and Physiological/Clinical Implications

Significance: The vasculature responds to the respiratory needs of tissue by modulating luminal diameter through smooth muscle constriction or relaxation. Coronary perfusion, diastolic function, and coronary flow reserve are drastically reduced with aging. This loss of blood flow contributes to and exacerbates pathological processes such as angina pectoris, atherosclerosis, and coronary artery and microvascular disease. Recent Advances: Increased attention has recently been given to defining mechanisms behind aging-mediated loss of vascular function and development of therapeutic strategies to restore youthful vascular responsiveness. The ultimate goal aims at providing new avenues for symptom management, reversal of tissue damage, and preventing or delaying of aging-induced vascular damage and dysfunction in the first place. Critical Issues: Our major objective is to describe how aging-associated mitochondrial dysfunction contributes to endothelial and smooth muscle dysfunction via dysregulated reactive oxygen species production, the clinical impact of this phenomenon, and to discuss emerging therapeutic strategies. Pathological changes in regulation of mitochondrial oxidative and nitrosative balance (Section 1) and mitochondrial dynamics of fission/fusion (Section 2) have widespread effects on the mechanisms underlying the ability of the vasculature to relax, leading to hyperconstriction with aging. We will focus on flow-mediated dilation, endothelial hyperpolarizing factors (Sections 3 and 4), and adrenergic receptors (Section 5), as outlined in Figure 1. The clinical implications of these changes on major adverse cardiac events and mortality are described (Section 6). Future Directions: We discuss antioxidative therapeutic strategies currently in development to restore mitochondrial redox homeostasis and subsequently vascular function and evaluate their potential clinical impact (Section 7). Antioxid. Redox Signal. 35, 974-1015.

Nitric Oxide as a Central Molecule in Hypertension: Focus on the Vasorelaxant Activity of New Nitric Oxide Donors

Cardiovascular diseases include all types of disorders related to the heart or blood vessels. High blood pressure is an important risk factor for cardiac complications and pathological disorders. An increase in circulating angiotensin-II is a potent stimulus for the expression of reactive oxygen species and pro-inflammatory cytokines that activate oxidative stress, perpetuating a deleterious effect in hypertension. Studies demonstrate the capacity of NO to prevent platelet or leukocyte activation and adhesion and inhibition of proliferation, as well as to modulate inflammatory or anti-inflammatory reactions and migration of vascular smooth muscle cells. However, in conditions of low availability of NO, such as during hypertension, these processes are impaired. Currently, there is great interest in the development of compounds capable of releasing NO in a modulated and stable way. Accordingly, compounds containing metal ions coupled to NO are being investigated and are widely recognized as having great relevance in the treatment of different diseases. Therefore, the exogenous administration of NO is an attractive and pharmacological alternative in the study and treatment of hypertension. The present review summarizes the role of nitric oxide in hypertension, focusing on the role of new NO donors, particularly the metal-based drugs and their protagonist activity in vascular function.

Quantifying the Effect of Topical Nitroglycerin on Random Pattern Flap Perfusion in a Rodent Model: An Application of the ViOptix Intra.Ox for Dynamic Flap Perfusion Assessment and Salvage

BACKGROUND

Near-infrared spectroscopy can detect changes in tissue oxygenation postoperatively that predict flap necrosis. The authors hypothesized that this technology can be applied along with topical nitroglycerin to measure an improvement in tissue oxygenation that correlates with tissue salvage.

METHODS

Dorsal, random pattern flaps measuring 10 × 3 cm were raised using Sprague-Dawley rats. Tissue oxygenation was measured after flap elevation in 10 locations using the ViOptix Intra.Ox. Animals were divided into three groups that received 30 mg of topical nitroglycerin daily, twice-daily, or not at all. Oxygenation measurements were repeated on postoperative day 1 and animals were euthanized on day 7 and evaluated for tissue necrosis.

RESULTS

Tissue necrosis was greatest in controls (51.3 mm) compared to daily (28.8 mm) and twice-daily nitroglycerin (18.8 mm; p = 0.035). Three flap perfusion zones were identified: healthy (proximal, 50 mm), necrotic (distal, 20 mm), and watershed. Immediate postoperative tissue oxygenation was highest in healthy tissue (57.2 percent) and decreased to 33.0 and 19.3 percent in the watershed and necrotic zones, respectively (p < 0.001). One day after treatment with nitroglycerin, oxygenation in the healthy zone did not increase significantly (mean difference, -1.5 percent). The watershed (17.8 percent; p < 0.001) and necrotic zones (16.3 percent; p <0.001) did exhibit significant improvements that were greater than those measured in control tissues (7.9 percent; both p < 0.001).

CONCLUSIONS

Serial perfusion assessment using the ViOptix Intra.Ox measured a significant improvement in flap oxygenation after treatment with topical nitroglycerin. Within the watershed area of the flap, this increase in tissue oxygenation was associated with the salvage of ischemic tissue.

Metoprolol combined with nicorandil on unstable angina pectoris can reduce incidence of cardiovascular events and inflammatory reactions

OBJECTIVE

This research was designed to investigate the efficacy of metoprolol combined with nicorandil on unstable angina pectoris (UAP).

METHODS

Totally 174 UAP patients treated in the Laixi City People's Hospital from May 2017 to December 2019 were taken as the research objects. They were divided into the control (n=79, CG) and joint (n=95) groups (JG). Patients in the CG were treated with metoprolol, while those in the JG were treated with nicorandil. The clinical efficacy, adverse events and inflammatory reactions were observed.

RESULTS

The effective rate of the JG was better than that of the CG after treatment. There were no additional adverse reactions, and the incidence of cardiovascular events reduced. The changes of cardiac function manifested that the left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD) in the JG were lower than those in the CG, while the left ventricular ejection fraction (LVEF) was higher. In addition, the serum levels of total cholesterol (TC), triglyceride (TG), high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) in the JG were lower than those in the CG.

CONCLUSION

Metoprolol combined with nicorandil is effective for UAP patients, which reduces the incidence of cardiovascular adverse events and inhibits inflammatory reactions.

Tailoring the management of hypertension to comorbidities

PURPOSE OF REVIEW

In this article, we review the most current evidence for initiation and maintenance of various antihypertension (HTN) drug classes, including other misconceptions with respect to common comorbidities in patients with HTN.

RECENT FINDINGS

Although the currently available anti-HTN agents have broad applicability in treating HTN, additional agents, such as angiotensin receptor-neprilysin inhibitors and novel nonsteroidal mineralocorticoid antagonists, have recently gained clinical significance. In addition, there have been some anecdotal concerns regarding the adverse effects, indications, and risks of COVID-19 infection/mortality when using certain anti-HTN agents.

SUMMARY

Current guidelines currently address the treatment of primary HTN. However, isolated HTN is uncommon and often involves comorbid diseases that require specific regimentation. Several experimental medications are currently in late-stage trials showing potential superiority over current drugs that are available in the market.

Management of refractory angina: an update

Despite the use of anti-anginal drugs and/or percutaneous coronary interventions (PCI) or coronary artery bypass grafting, the proportion of patients with coronary artery disease who have daily or weekly angina ranges from 2% to 24%. Refractory angina refers to long-lasting symptoms (for >3 months) due to established reversible ischaemia, which cannot be controlled by escalating medical therapy with the use of 2nd- and 3rd-line pharmacological agents, bypass grafting, or stenting. While there is uncertain prognostic benefit, the treatment of refractory angina is important to improve the quality of life of the patients affected. This review focuses on conventional pharmacological approaches to treating refractory angina, including guideline directed drug combination and dosages. The symptomatic and prognostic impact of advanced and novel revascularization strategies such as chronic total occlusion PCI, transmyocardial laser revascularization, coronary sinus occlusion, radiation therapy for recurrent restenosis, and spinal cord stimulation are also covered and recommendations of the 2019 ESC Guidelines on the Diagnosis and Management of Chronic Coronary Syndromes discussed. Finally, the potential clinical use of current angiogenetic and stem cell therapies in reducing ischaemia and/or pain is evaluated.

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.

Aortic disease in Marfan syndrome is caused by overactivation of sGC-PRKG signaling by NO

Thoracic aortic aneurysm, as occurs in Marfan syndrome, is generally asymptomatic until dissection or rupture, requiring surgical intervention as the only available treatment. Here, we show that nitric oxide (NO) signaling dysregulates actin cytoskeleton dynamics in Marfan Syndrome smooth muscle cells and that NO-donors induce Marfan-like aortopathy in wild-type mice, indicating that a marked increase in NO suffices to induce aortopathy. Levels of nitrated proteins are higher in plasma from Marfan patients and mice and in aortic tissue from Marfan mice than in control samples, indicating elevated circulating and tissue NO. Soluble guanylate cyclase and cGMP-dependent protein kinase are both activated in Marfan patients and mice and in wild-type mice treated with NO-donors, as shown by increased plasma cGMP and pVASP-S239 staining in aortic tissue. Marfan aortopathy in mice is reverted by pharmacological inhibition of soluble guanylate cyclase and cGMP-dependent protein kinase and lentiviral-mediated Prkg1 silencing. These findings identify potential biomarkers for monitoring Marfan Syndrome in patients and urge evaluation of cGMP-dependent protein kinase and soluble guanylate cyclase as therapeutic targets.

Aortic aneurysm and dissection, the major problem linked to Marfan syndrome (MFS), lacks effective pharmacological treatment. Here, the authors show that the NO pathway is overactivated in MFS and that inhibition of guanylate cyclase and cGMP-dependent protein kinase reverts MFS aortopathy in mice.

Parental Occupation and Risk of Childhood Retinoblastoma in Denmark

OBJECTIVE

Retinoblastoma is the most common primary intraocular tumor affecting children. We examine the role of parental occupational exposures and risk of retinoblastoma among offspring.

METHODS

Our population-based case-control study linked data from four nationwide Danish registries and included all cases of retinoblastoma diagnosed in Danish children (<5 y, n = 144) between 1975 and 2014. We focused on two biologically relevant time periods: 90 days preconception to conception for fathers; conception to birth for mothers. Parents were grouped into major industry headings created from Danish industry codes.

RESULTS

We observed increased risk of all retinoblastoma for children of fathers in the food and drink industry and iron and metal industry. Bilateral disease was associated with paternal work in manufacturing and land transportation.

CONCLUSION

Our results suggest that some occupational exposures may increase the risk of childhood sporadic retinoblastoma.

The Efficacy and Safety of Nicorandil for Periprocedural Myocardial Injury in Patients Undergoing PCI: A Meta-Analysis

Purpose

To evaluate the efficacy and safety of nicorandil for periprocedural myocardial injury in patients undergoing PCI through meta-analysis of randomized controlled trials.

Methods

We analyzed the clinical data of patients including the incidence of periprocedural myocardial injury (PMI) and major adverse cardiovascular events (MACE) from selected articles. RCTs were retrieved from medical literature databases. RR and 95% confidence intervals (CI) were calculated to compare the endpoints.

Results

In total, 15 articles (16 trial comparisons) were retrieved which contained 2221 patients. In general, 1130 patients (50.9%) were randomized to the experimental group, whereas 1091 patients (49.1%) were randomized to the control group. The result showed that nicorandil significantly reduced the incidence of PMI and MACE after PCI compared to the control group.

Conclusions

Overall, early use of nicorandil in patients undergoing percutaneous coronary intervention (PCI) was associated with a significant reduction of PMI and MACE.

Efficacy and Safety of Nicorandil in Preventing Contrast-Induced Nephropathy after Elective Percutaneous Coronary Intervention: A Pooled Analysis of 1229 Patients

Background

Nicorandil in reducing contrast-induced nephropathy (CIN) following elective percutaneous coronary intervention (PCI) is an inconsistent practice. This article aims to evaluate the efficacy and safety of nicorandil in preventing CIN after elective PCI.

Methods

This is a pooled analysis of patients treated with elective PCI. The primary outcome was the incidence of CIN. The secondary outcomes were major adverse events, including mortality, heart failure, recurrent myocardial infarction, stroke, and renal replacement therapy.

Results

A total of 1229 patients were recruited in our study. With statistical significance, nicorandil lowered the risk of CIN (odds ratio = 0.26; 95% confidence interval = 0.16–0.44; P < 0.00001; I² = 0%) in patients who underwent elective PCI. In addition, no significant differences were observed in the incidence of mortality, heart failure, recurrent myocardial infarction, stroke, and renal replacement therapy between the two groups (P > 0.05).

Conclusions

Our article indicated that nicorandil could prevent CIN without increasing the major adverse events. Furthermore, sufficiently powered and randomized clinical studies are still needed in order to determine the role of nicorandil in preventing CIN after elective PCI.

The effect of nicorandil in patients with cardiac syndrome X: A meta-analysis of randomized controlled trials

BACKGROUND

The prevalence of cardiac syndrome X (CSX) is considerable. Some patients show recurrent angina attacks and have a poor prognosis. However, the knowledge of CSX pathophysiological mechanism is still limited, and the treatment fails to achieve a satisfactory suppression of symptoms. Nicorandil has a beneficial effect on improving coronary microvascular dysfunction (CMD). This study aims to evaluate the clinical effects and safety of nicorandil on CSX patients.

METHODS

The Cochrane Library, Pubmed, EMBASE, ClinicalTrials.gov and 4 Chinese databases were searched to identify relevant studies. The Cochrane "Risk of bias" tool was used to assess the methodological quality of eligible studies. Meta-analysis was performed by RevMan 5.3 software. The Eggers test and meta-regression were performed by software Stata 14.0. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

Twenty four randomized controlled trials (RCTs) involving 2323 patients were included. Most of the included studies were classified as having an unclear risk of bias because of poor reported methodology. The main outcomes are angina symptoms improvement, resting electrocardiogram (ECG) improvement, treadmill test result, and endothelial function. Meta-analysis showed that nicorandil had some benefit on improving angina symptoms (RR 1.24, 95% CI 1.19 to 1.29, I = 20%, P < .00001), resting ECG (RR = 1.24, 95% IC: 1.15 to 1.33, I = 0%, P < .00001), and prolonged the time to 1 mm ST-segment depression in treadmill test result (WMD = 38.41, 95% IC: 18.46 to 58.36, I = 0%, P = .0002). Besides nicorandil could reduce the level of endothelin-1 (ET-1) (SMD = -2.22, 95% IC: -2.61 to -1.83, I = 77%, P < .00001) and increase the level of nitric oxide (NO) (WMD = 27.45, 95% IC: 125.65 to 29.24, I = 81%, P < .00001). No serious adverse drug event was reported. The Eggers test showed that significant statistical publication bias was detected (Eggers test P = .000). The quality of evidence ranged from very low to low.

CONCLUSIONS

Nicorandil shows the potential of improving angina symptoms, ECG, and endothelial dysfunction in patients with CSX. However, there is insufficient evidence for the clinical benefits of nicorandil due to the very low-quality evidence.

Practical catalytic nitration directly with commercial nitric acid for the preparation of aliphatic nitroesters

To pursue a sustainable and efficient approach for aliphatic nitroester preparation from alcohol, europium-triflate-catalyzed nitration, which directly uses commercial nitric acid, has been successfully developed. Gram scalability with operational ease showed its practicability.

Ischaemia with no obstructive coronary arteries

Ischaemia with no obstructive coronary arteries (INOCA) is a common ischaemic heart disease with a female preponderance, mostly due to underlying coronary vascular dysfunction comprising coronary microvascular dysfunction and/or epicardial coronary vasospasm. Since standard ischaemia detection tests and coronary angiograms are not suitable to diagnose coronary vascular dysfunction, INOCA is often overlooked in current cardiology practice. Future research, including large outcome trials, is much awaited. Yet, adequate diagnosis is possible and treatment options are available and vital to reduce symptoms and most probably improve cardiovascular prognosis. This review intends to give a brief overview of the clinical presentation, underlying pathophysiology, and the diagnostic and treatment options in patients with suspected INOCA.

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.

Potential Beneficial Effects of Vitamin D in Coronary Artery Disease

Vitamin D plays a pivotal role in bone homeostasis and calcium metabolism. However, recent research has indicated additional beneficial effects of vitamin D on the cardiovascular system. This review aims to elucidate if vitamin D can be used as an add-on treatment in coronary artery disease (CAD). Large-scale epidemiological studies have found a significant inverse association between serum 25(OH)-vitamin D levels and the prevalence of essential hypertension. Likewise, epidemiological data have suggested plasma levels of vitamin D to be inversely correlated to cardiac injury after acute myocardial infarction (MI). Remarkably, in vitro trials have showed that vitamin D can actively suppress the intracellular NF-κB pathway to decrease CAD progression. This is suggested as a mechanistic link to explain how vitamin D may decrease vascular inflammation and atherosclerosis. A review of randomized controlled trials with vitamin D supplementation showed ambiguous results. This may partly be explained by heterogeneous study groups. It is suggested that subgroups of diabetic patients may benefit more from vitamin D supplementation. Moreover, some studies have indicated that calcitriol rather than cholecalciferol exerts more potent beneficial effects on atherosclerosis and CAD. Therefore, further studies are required to clarify these assumptions.

Nicorandil alleviates apoptosis in diabetic cardiomyopathy through PI3K/Akt pathway

Nicorandil exerts myocardial protection through its antihypoxia and antioxidant effects. Here, we investigated whether it plays an anti‐apoptotic role in diabetic cardiomyopathy. Sprague‐Dawley rats were fed with high‐fat diet; then single intraperitoneal injection of streptozotocin was performed. Rats with fasting blood glucose (FBG) higher than 11.1 mmol/L were selected as models. Eight weeks after the models were built, rats were treated with nicorandil (7.5 mg/kg day and 15 mg/kg day respectively) for 4 weeks. H9c2 cardiomyocytes were treated with nicorandil and then stimulated with high glucose (33.3 mmol/L). TUNEL assay and level of bcl‐2, bax and caspase‐3 were measured. 5‐HD was used to inhibit nicorandil. Also, PI3K inhibitor (Miltefosine) and mTOR inhibitor (rapamycin) were used to inhibit PI3K/Akt pathway. The results revealed that nicorandil (both 7.5 mg/kg day and 15mg/kg day) treatment can increase the level of NO in the serum and eNOS in the heart of diabetic rats compared with the untreated diabetic group. Nicorandil can also improve relieve cardiac dysfunction and reduce the level of apoptosis. In vitro experiments, nicorandil (100 µmol) can attenuate the level of apoptosis stimulated by high glucose significantly in H9C2 cardiomyocyte compared with the untreated group. The effect of nicorandil on apoptosis was blocked by 5‐HD, and it was accompanied with inhibition of the phosphorylation of PI3K, Akt, eNOS, and mTOR. After inhibition of PI3K/Akt pathway, the protective effect of nicorandil is restrained. These results verified that as a NO donor, nicorandil can also inhibit apoptosis in diabetic cardiomyopathy which is mediated by PI3K/Akt pathway.

Vascular biomedicine in an era of chronic disease and multimorbidity

It is increasingly common that patients present with more than one disease and that diseases are chronic in nature. Cardiovascular conditions such as hypertension, heart failure and stroke, renal diseases and cardiometabolic conditions such as diabetes are prime examples of chronic diseases which pose major challenges in contemporary healthcare provision. The complex features of multimorbidity call for precision medicine approaches that take comorbidity and chronicity into account. The research basis of chronic disease and multimorbidity, however, is currently in its infancy. This applies to all domains including basic, translational and clinical science. In this article we call for development of new models, smarter use of existing models and better characterisation of vascular and cardiovascular phenotypes in studies not directly related to cardiovascular diseases. This has the potential to further improve the quality of translational research, papers in journals such as Clinical Science and ultimately translate into better patient care.

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.

Interrelation of liver vascularity to non-alcoholic fatty liver through a comparative study of the vasodilator effect of carvedilol or nicorandil in rats

AIM

An experimental study of the effect of two vasodilators, carvedilol (B blocker with alpha-antagonist) and nicorandil (NO donor) on nonalcoholic fatty liver (NAFLD) induced by hypercholesterolemia and fatty diet in rats through studying the possible anti-inflammatory and antioxidant mechanisms.

MAIN METHODS

The rats were divided into 4 groups (6 rats each): The first (negative control group). The second, third and fourth groups were fed with cholesterol and fat- enriched diet for one month that stopped and continued on the standard diet for another month without treatment in the second group but treated with carvedilol and nicorandil in the third and fourth group respectively.

KEY FINDINGS

They revealed that both improved NAFLD especially nicorandil treated proved by the reduction of liver enzymes (AST, ALT), the fatty infiltration determined histologically and biochemically (decrease liver triglycerides). This may be due to either being antioxidants (reduced malondialdehyde and elevated reduced glutathione) or anti-inflammatory (decreased of TNF-α) together with the reduction of insulin resistance and adiponectin elevation or gene expression (increased liver NF-κB and decreased eNOS expression) and finally maybe by their obvious effect on improvements of lipid parameters.

SIGNIFICANCE

Carvedilol and nicorandil improved NAFLD through the interrelationship between inflammatory cytokines, antioxidants and insulin resistance.

Impact of different nitrate therapies on long-term clinical outcomes of patients with vasospastic angina: A propensity score-matched analysis

BACKGROUND

Despite the short-term vasodilatory effects of nitrates, the prognostic effects of long-term nitrate therapy in patients with vasospastic angina (VSA) remains unclear. We investigated the prognostic impact of chronic nitrate therapy in VSA patients.

METHODS

Between January 2003 and December 2014, a total of 1154 VSA patients proven by ergonovine provocation tests were classified into nitrate (n=676) and non-nitrate (n=478) groups according to prescriptions for oral nitrates, including isosorbide mononitrate (ISMN) and nicorandil. The primary outcome was major adverse cardiovascular events (MACE), defined as a composite of cardiac death, myocardial infarction, any revascularization, or rehospitalization due to recurrent angina.

RESULTS

The nitrate group was found to have a higher risk of MACE (22.9% vs. 17.6%, hazard ratio [HR] 1.32, 95% confidence interval [CI] 1.01-1.73, p=0.043) than the non-nitrate group. After propensity score matching, the nitrate group had greater risks of MACE (HR 1.32, 95%CI 1.01-1.73, p=0.049). Patients who received the immediate-release formula of ISMN (HR 1.80, 95%CI 1.35-2.39, p<0.001) or were administered any forms of ISMN other than at bedtime (HR 1.90, 95%CI 1.41-2.57, p<0.001) had a significantly higher risk of MACE compared with the non-nitrate group. Nicorandil was shown to have a neutral effect on VSA patients (HR 1.11, 95%CI 0.73-1.69, p=0.62).

CONCLUSIONS

The long-term use of nitrate therapy was associated with increased risk of adverse cardiac events in VSA patients. The use of immediate-release ISMN or the administration of ISMN other than at bedtime was related with poor outcomes of VSA patients.

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.

Protective effects of nicorandil against cerebral injury in a swine cardiac arrest model

The present study investigated the effects of nicorandil on cerebral injury following cardiopulmonary resuscitation (CPR) in a swine model of cardiac arrest. CPR was performed on swine following 4 min induced ventricular fibrillation. Surviving animals were randomly divided into 3 groups: A nicorandil group (n=8), a control group (n=8) and a sham group (n=4). The sham group underwent the same surgical procedure to imitate cardiac arrest, but ventricular fibrillation was not induced. When the earliest observable return of spontaneous circulation (ROSC) was detected, the nicorandil and control groups received injections of nicorandil and saline, respectively. Swine serum was collected at baseline and 5 min, 0.5, 3 and 6 h following ROSC. Serum levels of neuron-specific enolase (NSE), S100β, tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) were measured using ELISA. Animals were euthanized and brain tissue samples were collected and assessed using light and electron microscopy 6 h following ROSC. The expression of aquaporin-4 (AQP-4) in the brain tissue was measured using western blotting. Malondialdehyde (MDA) and glutathione (GSH) levels in the brain tissue were determined using thiobarbituric acid and thiobenzoic acid colorimetric methods, respectively. Serum NSE and S100β were significantly higher in the nicorandil and control groups following CPR, compared with baseline (P<0.05). Additionally, NSE and S100β levels were significantly lower in the nicorandil group compared with the control (P<0.05). Pathological examinations and electron microscopy indicated that nicorandil reduced brain tissue damage. TNF-α and IL-6 levels were significantly decreased in the nicorandil group compared with the control group (P<0.05). Furthermore, AQP-4 expression in brain tissue 6 h following ROSC was significantly lower in the nicorandil group compared with the control group (P<0.05). MDA and GSH levels in swine brain tissue decreased and increased, respectively, in the nicorandil group compared with the control group (P<0.05). The results of the present study demonstrate that nicorandil exerts a protective effect against brain injury following cardiac arrest by reducing oxidative damage, inflammatory responses and brain edema post-ROSC.

Nicorandil and Long-acting Nitrates: Vasodilator Therapies for the Management of Chronic Stable Angina Pectoris

Nicorandil and long-acting nitrates are vasodilatory drugs used commonly in the management of chronic stable angina pectoris. Both nicorandil and long-acting nitrates exert anti-angina properties via activation of nitric oxide (NO) signalling pathways, triggering vascular smooth muscle cell relaxation. Nicorandil has additional actions as an arterial K⁺ _ATP channel agonist, resulting in more "balanced" arterial and venous vasodilatation than nitrates. Ultimately, these drugs prevent angina symptoms through reductions in preload and diastolic wall tension and, to a lesser extent, epicardial coronary artery dilatation and lowering of systemic blood pressure. While there is some evidence to suggest a modest reduction in cardiovascular events among patients with stable angina treated with nicorandil compared to placebo, this prognostic benefit has yet to be proven conclusively. In contrast, there is emerging evidence to suggest that chronic use of long-acting nitrates might cause endothelial dysfunction and increased cardiovascular risk in some patients.

The Role of Nitroglycerin and Other Nitrogen Oxides in Cardiovascular Therapeutics

The use of nitroglycerin in the treatment of angina pectoris began not long after its original synthesis in 1847. Since then, the discovery of nitric oxide as a biological effector and better understanding of its roles in vasodilation, cell permeability, platelet function, inflammation, and other vascular processes have advanced our knowledge of the hemodynamic (mostly mediated through vasodilation of capacitance and conductance arteries) and nonhemodynamic effects of organic nitrate therapy, via both nitric oxide-dependent and -independent mechanisms. Nitrates are rapidly absorbed from mucous membranes, the gastrointestinal tract, and the skin; thus, nitroglycerin is available in a number of preparations for delivery via several routes: oral tablets, sublingual tablets, buccal tablets, sublingual spray, transdermal ointment, and transdermal patch, as well as intravenous formulations. Organic nitrates are commonly used in the treatment of cardiovascular disease, but clinical data limit their use mostly to the treatment of angina. They are also used in the treatment of subsets of patients with heart failure and pulmonary hypertension. One major limitation of the use of nitrates is the development of tolerance. Although several agents have been studied for use in the prevention of nitrate tolerance, none are currently recommended owing to a paucity of supportive clinical data. Only 1 method of preventing nitrate tolerance remains widely accepted: the use of a dosing strategy that provides an interval of no or low nitrate exposure during each 24-h period. Nitric oxide's important role in several cardiovascular disease mechanisms continues to drive research toward finding novel ways to affect both endogenous and exogenous sources of this key molecular mediator.