Ranolazine: An Old Drug with Emerging Potential; Lessons from Pre-Clinical and Clinical Investigations for Possible Repositioning

Ischemic heart disease is a significant public health problem with high mortality and morbidity. Extensive scientific investigations from basic sciences to clinics revealed multilevel alterations from metabolic imbalance, altered electrophysiology, and defective Ca2+/Na+ homeostasis leading to lethal arrhythmias. Despite the recent identification of numerous molecular targets with potential therapeutic interest, a pragmatic observation on the current pharmacological R&D output confirms the lack of new therapeutic offers to patients. By contrast, from recent trials, molecules initially developed for other fields of application have shown cardiovascular benefits, as illustrated with some anti-diabetic agents, regardless of the presence or absence of diabetes, emphasizing the clear advantage of “old” drug repositioning. Ranolazine is approved as an antianginal agent and has a favorable overall safety profile. This drug, developed initially as a metabolic modulator, was also identified as an inhibitor of the cardiac late Na+ current, although it also blocks other ionic currents, including the hERG/Ikr K+ current. The latter actions have been involved in this drug’s antiarrhythmic effects, both on supraventricular and ventricular arrhythmias (VA). However, despite initial enthusiasm and promising development in the cardiovascular field, ranolazine is only authorized as a second-line treatment in patients with chronic angina pectoris, notwithstanding its antiarrhythmic properties. A plausible reason for this is the apparent difficulty in linking the clinical benefits to the multiple molecular actions of this drug. Here, we review ranolazine’s experimental and clinical knowledge on cardiac metabolism and arrhythmias. We also highlight advances in understanding novel effects on neurons, the vascular system, skeletal muscles, blood sugar control, and cancer, which may open the way to reposition this “old” drug alone or in combination with other medications.

695 Upregulated monocyte expression of PLIN2 is associated with plaque instability in coronary artery disease

Aims Perilipin 2 (PLIN2), a protein associated with intracellular lipid droplets (LDs), is involved in lipid metabolism of macrophages resident in atherosclerotic plaques and its up-regulation leads to LDs accumulation. LDs enlargement results in the macrophage transformation into foam cells, a key step for the onset of atherosclerosis. In the present study, we investigated the role of PLIN2 and its regulation mechanisms in atherosclerosis and plaque instability in patients with a diagnosis of ST-elevation myocardial infarction (STEMI) and stable chronic angina (SA). Methods and results We enrolled 120 patients with a diagnosis of STEMI and 42 SA patients with symptoms of stable effort angina lasting more than 12 months. Peripheral blood mononuclear cells (PBMCs) were isolated from EDTA whole blood samples through standard gradient centrifugation over Ficoll-Hypaque. Monocytes were purified through indirect magnetic labelling of PBMCs. PLIN2 mRNA expression was investigated by Real Time-PCR and PLIN2 protein level was analysed in CD14+ monocytes by flow cytometry. Proteasome activity was assayed using AMC-tagged peptide substrate (Succ-LLVY-AMC), which releases free highly fluorescent AMC (Ex/Em 350/440 nm) in the presence of proteolytic activity. In CD14+ monocyte, PLIN2 protein expression was significantly increased in STEMI as compared to SA patients (P < 0.001), while PLIN2 mRNA level was not different in the two groups (P = n.s.). Despite proteasome activity was higher in STEMI as compared to SA patients (P < 0.001), significant inverse correlations were evident between PLIN2 levels and proteasome activity in the two groups (P = 0.05). Conclusions CD14+ monocyte PLIN2 protein expression was higher in STEMI as compared to SA patients suggesting an involvement in plaque instability. Despite proteasome activity was higher in STEMI patients, probably due to the elevated inflammatory burden, PLIN2 could escape proteasome degradation in a more efficient manner in STEMI as compared to SA patients.

Comparative 4-year risk and type of hospital admission among homeless and housed emergency department attendees: longitudinal study of hospital records in England 2013–2018

ObjectivesPeople experiencing homelessness are frequent users of secondary care. Currently, there is no study of potentially preventable admissions for homeless patients in England. We aim to estimate the number of potentially preventable hospital admissions for homeless patients and compare to housed patients with similar characteristics.DesignRetrospective matched cohort study.SettingHospitals in England.Participants16 161 homeless patients and 74 780 housed patients aged 16–75 years who attended an emergency department (ED) in England in 2013/2014, matched on the basis of age, sex, ED attended and primary diagnosis.Primary and secondary outcome measuresAnnual counts of admissions, emergency admissions, ambulatory care-sensitive (ACS) emergency admissions, acute ACS emergency admissions and chronic ACS emergency admissions over the following 4 years (2014/2015–2017/2018). We additionally compare the prevalence of specific ACS conditions for homeless and housed patients.ResultsMean admissions per 1000 patients per year were 470 for homeless patients and 230 for housed patients. Adjusted for confounders, annual admissions were 1.79 times higher (incident rate ratio (IRR)=1.79; 95% CI 1.69 to 1.90), emergency admissions 2.08 times higher (IRR=2.08; 95% CI 1.95 to 2.21) and ACS admissions 1.65 times higher (IRR=1.65; 95% CI 1.51 to 1.80), compared with housed patients. The effect was greater for acute (IRR=1.78; 95% CI 1.64 to 1.93) than chronic (IRR=1.45; 95% CI 1.27 to 1.66) ACS conditions. ACS conditions that were relatively more common for homeless patients were cellulitis, convulsions/epilepsy and chronic angina.ConclusionsHomeless patients use hospital services at higher rates than housed patients, particularly emergency admissions. ACS admissions of homeless patients are higher which suggests some admissions may be potentially preventable with improved access to primary care. However, these admissions comprise a small share of total admissions.

A novel outpatient regimen in management of fluoropyrimidine-induced cardiotoxicity.

e15613 Background: Fluoropyrimidines, such as 5-fluorouracil (5-FU) and capecitabine, are commonly used chemotherapies for solid tumors, and essential for curative intent treatment of colorectal cancer. But sometimes, their use may be limited by cardiac toxicity limiting the possibility of cure in some patients. Cardiotoxicity could be asymptomatic (EKG changes) or manifested as chest pain, arrhythmias, acute coronary syndrome or death. Rechallenging may be daunting and it may result in interruption or even discontinuation of planned chemo. Traditionally, nitrates and/or IV/oral calcium channel blockers (CCB) have been used for management of fluoropyrimidine-induced cardiotoxicity but without much benefit. Ranolazine, an oral antianginal drug approved for chronic angina, diminishes myocardial ischemia by reducing calcium overload caused by inhibition of late sodium current and it does not affect heart rate or blood pressure. Our objective was to evaluate the efficacy of our novel approach using ranolazine with other traditional drugs. Methods: 8 patients (median age 49.5 yrs) with fluoropyrimidine induced cardiotoxicity were retrospectively analyzed. They were rechallenged with the planned fluoropyrimidine regimen with our 3 drug cardioprotective regimen (KU protocol). This included oral Ranolazine 1000mg BID and Amlodipine 2.5 mg daily to start the day before starting 5FU infusion/oral capecitabine and to continue it until the day after completion of infusion/treatment, and Nitroglycerin paste 1 inch every 6 hours starting before infusion and continue until it was completed. These meds were discontinued upon completion of chemo. Results: 8 patients were rechallenged with fluoropyrimidine utilizing KU protocol, 6 patients (75%) were able to complete previously planned fluoropyrimidine regimen. One pt (*) discontinued capecitabine due to recurrent chest pain and treatment was switched to 5FU based regimen with KU protocol, which pt was able to complete without chest pain. Another pt (**), 5FU was stopped due to severe diarrhea, not due to cardiotoxicity. All pts tolerated KU protocol well. Conclusions: In our small, single center experience, we were able to safely and effectively rechallenge pts with fluoropyrimidines and complete curative intent treatment with our KU protocol. This protocol uses FDA approved oral and transcutaneous drugs without requiring a healthcare personnel to administer an IV CCB that can cause precipitous bradycardia and/or hypotension. Our results need validation in a larger cohort. [Table: see text]

Efficacy and Safety of Combined Treament with Ivabradine and Metoprolol in Patients with Stable Angina Pectoris – a Systematic Review

This article presents results of a systematic review, which was designed for evaluating the effect of combination treatment with ivabradine and metoprolol on heart rate, frequency of angina attacks, frequency of using short-acting nitrates, and angina severity. The analysis included data from three large observational studies on efficacy of the ivabradine and metoprolol tartrate combination in patients with chronic angina. Results of the analysis supported the efficacy of the metoprolol and ivabradine combination in clinical practice, which provided effective decreases in the heart rate, frequency of angina attacks, requirement for short-acting nitrates, and alleviation of angina severity. The studies demonstrated good tolerability of this treatment.

Effects of Statin Treatment on Patients with Angina and Normal or Nearly Normal Angiograms

This article offers an updated and comprehensive overview of major findings on the effects of statin treatment in patients with chronic angina but without any epicardial coronary artery with obstructive lesion.

P2245Sex differences in the in-vivo markers of platelet activation among patients with ischemic heart disease: insights from the EVA study

Background/Introduction Ischemic heart diseases (IHD) are not synonymous with obstructive flow-limiting coronary artery disease (CAD), especially in women. Platelet dysfunction is suggested as a potential mechanism favouring ischemia in non-obstructive CAD. However, it is unknown whether sex differences in platelet function of patients with non-obstructive CAD exist. Purpose We assessed for sex differences in in-vivo markers of platelet activation among patients with the acute coronary syndrome and chronic stable angina, with or without obstructive CAD Methods From the “Endocrine Vascular disease Approach” (EVA) study, we selected IHD patients undergoing urgent or elective coronary angiography with complete baseline clinical characteristics and angiographic data. Non-obstructive CAD was defined as the presence of coronary stenosis <50%. Thromboxane B2 (TxB2) and soluble P-selectin (sP-s) were measured at baseline. A sex-stratified analysis of platelet biomarkers was performed. Results Among two-hundred-seventy-seven patients (mean age 67±11, 37% women), non-obstructive CAD was documented in 25% of patients. Acute coronary syndrome (ACS) was the reason for angiography in 61% of cases. Women had more frequently ACS, as compared with men (54.8% vs 41.3%, p=0.001), with predominantly non-obstructive CAD. Median serum TxB2 (121.5 [92.7–174.0] vs 103.5 [83.0–140.2] pg/ml, p=0.005) and plasma sP-s (27.0 [18.7–35.0] vs 22.0 [16.0–30.0] ng/ml, p=0.006) levels were higher in patients with ACS as compared with the ones with stable chronic angina. The median concentration of TxB2 was significantly increased in women as compared with men, regardless of the clinical presentation and the coronary stenosis degree (all comparison, p<0.001). However, women with non-obstructive CAD were the group with the highest serum levels of TxB2 (140.0 [111.0–152.0] pg/ml). Sex differences in the plasma sP-s level were also observed among patients with stable chronic angina (women, 26 [20.0–34.0] vs men, 21 [16.6–27.7] ng/ml, p=0.002) and with non-obstructive CAD (women, 26 [20.5–34.5] vs men, 18.5 [16.6–26.0] ng/ml, p=0.003). Conclusion(s) Women with IHD and non-obstructive CAD had increased level of TxB2 and sP-s as compared with men, independently by the clinical presentation. Further investigations are warranted to verify the role of platelet hyperactivation in the pathogenesis of myocardial ischemia with non-obstructive coronary artery disease among women. Acknowledgement/Funding Scientific Independence of Young Researchers Program (RBSI14HNVT) - Ministry of Education, University and Research (MIUR)