Impact of adenosine A2a receptor polymorphism rs5751876 on platelet reactivity in ticagrelor treated patients.

Dual antiplatelet therapy constitutes a key point in the management of patients with acute coronary syndromes. In particular, ticagrelor, an ADP-antagonist, can provide a more potent and predictable platelet inhibition as compared to clopidogrel, and adenosine-mediated pathways have been involved in its beneficial effects on mortality and myocardial perfusion. However, a quote of patients still displays a suboptimal platelet inhibition on ticagrelor, and, while the role of genetics in conditioning clopidogrel resistance is well established, few data have been reported for ticagrelor. We investigated the impact of rs5751876 C > T polymorphism of adenosine A2a receptor (ADORA2a) on platelet reactivity in patients during chronic treatment with ticagrelor. We included patients treated with ASA and ticagrelor for a recent ACS or elective coronary revascularization. Platelet reactivity was assessed at 30-90 days post-discharge by multiple-electrode aggregometry. HRPR for ticagrelor was defined as ADP-test results >417 AU*min. Genetic analysis was performed to assess the presence of rs5751876 C > T polymorphism of ADORA2a receptor. We included 244 patients in our study, 174 (71.3%) patients carried the polymorphism (T allele), 51 (20.9%) of them in homozygosis (T/T). C-allele carriers (homozygotes C/C and heterozygotes C/T) showed no difference in baseline characteristics but for lower HDL-cholesterol (p = 0.01). An absolute lower rate of HRPR on ticagrelor was observed in homozygotes T/T (p = 0.03). At multivariate analysis, C allele carriage was independently associated with the rate of HRPR on ticagrelor (adjusted OR[95%CI] = 4.63[1.02-21.01], p = 0.048). Our study results showed a significant independent association between rs5751876 allele C carriage and a higher rate of high residual platelet reactivity in patients on ticagrelor after a recent ACS or PCI.

Combined use of Kappa Free Light Chain Index and Isoelectrofocusing of Cerebro-Spinal Fluid in Diagnosing Multiple Sclerosis: Performances and Costs.

BACKGROUND: Isoelectrofocusing (IEF) to detect oligoclonal bands (OBCs) in cerebrospinal fluid (CSF) is the gold standard approach for evaluating intrathecal immunoglobulin synthesis in multiple sclerosis (MS) but the kappa free light chain index (KFLCi) is emerging as an alternative marker, and the combined/sequential uses of IEF and KFLCi have never been challenged. METHODS: CSF and serum albumin, IgG, kFLC and lFLC were measured by nephelometry; albumin, IgG and kFLC quotients as well as Link and kFLC indexes were calculated; OCBs were evaluated by immunofixation. A total of 150 consecutive patients: 48 with MS, 32 with other neurological inflammatory diseases (NID), 62 with neurological non-inflammatory diseases (NNID), and 8 without any detectable neurological disease (NND) were investigated. RESULTS: Both IEF and KFLCi showed a similar accuracy as diagnostic tests for multiple sclerosis. The high sensitivity and specificity associated with the lower cost of KFLCi suggested to use this test first, followed by IEF as a confirmative procedure. The sequential use of IEF and KFLCi showed high diagnostic efficiency with cost reduction of 43 and 21%, if compared to the contemporary use of both tests, or the unique use of IEF in all patients. CONCLUSIONS: The "sequential testing" using KFLCi followed by IEF in MS represents an optimal procedure with accurate performance and lower costs.

Gender Differences in Platelet Reactivity in Patients Receiving Dual Antiplatelet Therapy.

BACKGROUND: Cardiovascular risk is still underestimated in women, experiencing higher mortality and worse prognosis after acute cardiovascular events. Gender differences have been reported in thrombotic and hemorrhagic risk during dual antiplatelet therapy (DAPT), thus suggesting a potential variability in platelet reactivity according to sex. The aim of the present study was to assess the role of gender on platelet function and the prevalence of high-on treatment residual platelet reactivity (HRPR) during DAPT in patients with recent acute coronary syndrome or percutaneous coronary revascularization. METHODS: Patients treated with DAPT (ASA and clopidogrel or ticagrelor) were scheduled for platelet function assessment at 30-90 days post-discharge. By whole blood impedance aggregometry, HRPR was considered for ASPI test >862 AU*min (for ASA) and ADP test values ≥417 AU*min (for ADP-antagonists). RESULTS: We included 541 patients on DAPT, 122 (22.6 %) of whom were females. Females were older (p < 0.001), displayed more frequently hypercholesterolemia (p = 0.003), renal failure (p = 0.04), acute presentation (p < 0.001), higher cholesterol levels and platelets count (p < 0.001). Inverse association was demonstrated with smoking (p < 0.001), previous PCI (p = 0.04) and statin use (p = 0.03), creatinine and haemoglobin (p < 0.001). Female gender did not influence mean platelet reactivity or the prevalence of HRPR for ASA (1.7 % vs 1.4 %, OR[95%CI] = 1.14[0.17-4.36], p = 0.99, adjusted OR[95%CI] = 1.54[0.20-11.6], p = 0.68) or ADP-antagonists (26.3 % vs 22.8 %, OR[95%CI] = 1.17[0.52-1.34], p = 0.45, adjusted OR[95%CI] = 1.05[0.59-1.86], p = 0.87). Results did not change when considering separately the 309 patients treated with clopidogrel (34 % vs 31.3 %, OR[95%CI] = 1.13[0.62-2.07], p = 0.76, adjusted OR[95%CI] = 1.35[0.63-2.9], p = 0.44 for females vs males), or patients (n = 232) on ticagrelor (20.4 % vs 11.1 %, OR[95%CI] = 2.27[0.99-5.17], p = 0.06 for females vs males), confirmed after correction for baseline differences (adjusted OR[95%CI] = 1.21[0.28-2.29], p = 0.68). CONCLUSION: In patients receiving dual antiplatelet therapy, gender does not impact on the prevalence of high-on treatment residual platelet reactivity (HRPR) with the major antiplatelet agents ASA, clopidogrel or ticagrelor.

Immature platelet fraction and high-on treatment platelet reactivity with ticagrelor in patients with acute coronary syndromes.

Residual high-on treatment platelet reactivity (HRPR) has been associated with a 2-9 fold increased risk of acute ischemic events in patients with acute coronary syndromes or coronary stenting. However, the mechanism of suboptimal platelet inhibition are still poorly understood. Aim of present study was to evaluate the role of the percentage of reticulated platelets on HRPR with ticagrelor. In patients treated with ASA (100-160 mg) and ticagrelor (90 mg twice a day) platelet reactivity and the reticulated platelets fraction (immature platelets fraction, IPF) were assessed at 30-90 days after acute coronary syndrome. Aggregation was assessed by multiple-electrode aggregometry. HRPR was defined as ADP test >417 AU*min. Our population is represented by 190 patients, divided according to tertiles values of IPF (<2.5; 2.5-3.99; ≥4 %). Higher IPF was associated to a larger platelet volume and lower platelets count (p < 0.001), and inversely related with a history of previous coronary revascularization (p = 0.03). Twenty-one out of 190 (11.0 %) patients displayed HRPR. No difference in the levels of circulating IPF was found in patients with or without HRPR (p = 0.25), with no correlation between the rate of reticulated platelets and platelet reactivity at ADP test (r = -0.084, p = 0.26). In fact no association was observed between high levels of IPF and the occurrence of HRPR (adjusted OR[95 % CI] = 0.69[0.34-1,37], p = 0.28), even after correction for baseline differences. In patients treated with ticagrelor, the levels of circulating reticulated platelets assessed at 30-90 days post-ACS are not associated with platelet reactivity or the occurrence of HRPR.

Impact of diabetes on immature platelets fraction and its relationship with platelet reactivity in patients receiving dual antiplatelet therapy.

Contrasting data have been reported so far on the role of reticulated platelets in suboptimal response to antiplatelet therapies. In particular, still unexplored is whether they may contribute to explain the higher risk of thrombotic complications observed in diabetic patients. Aim of the present study was to evaluate the impact of diabetes on the levels of reticulated platelets and its relationship with high residual on-treatment platelet reactivity (HRPR) in patients receiving dual antiplatelet therapy. In patients treated with ASA (100-160 mg) and clopidogrel (75 mg daily) or ticagrelor (90 mg twice a day) platelet reactivity and the reticulated platelets fraction (immature platelets fraction, IPF) were assessed at 30-90 days post-discharge for an acute coronary syndrome or elective PCI. Aggregation was assessed by multiple-electrode aggregometry. We included 386 patients, 158 (40.9 %) diabetics. The percentage of IPF was similar in diabetic and non diabetic patients, both at baseline (3.5 ± 2.5 vs 3.6 ± 2.7 %, p = 0.91) and at 30-90 days re-assessment (3.3 ± 2.1 vs 3.5 ± 2.5 %, p = 0.30), with diabetes not emerging as an independent predictor of IPF above III tertile (adjusted OR [95 %CI] = 0.58 [0.30-1.09], p = 0.10). Diabetic patients displayed an enhanced platelet reactivity and a higher rate of HRPR with ADP antagonists (32.8 vs 22.5 %, p = 0.009). However, no association was found between the percentage of IPF and platelet function (r = -0.004; p = 0.95 for ASPI test, r = -0.04; p = 0.59 for ADP-mediated aggregation), or the rate of HRPR for ADP antagonsist across IPF tertiles. Results were similar for diabetics both receiving clopidogrel and ticagrelor. Diabetic patients display a higher platelet reactivity and suboptimal response to ADP-antagonists. However, the rate of reticulated platelets is neither influenced by diabetic status nor associated with an increased platelet reactivity among diabetic patients receiving dual antiplatelet therapy for a recent acute coronary syndrome or PCI.

Vitamin D levels and high-residual platelet reactivity in patients receiving dual antiplatelet therapy with clopidogrel or ticagrelor.

BACKGROUND: Suboptimal platelet inhibition still represents an important challenge, especially for patients undergoing percutaneous coronary interventions (PCIs). However, very few are known so far on the predictors of high-residual platelet reactivity (HRPR) despite antiplatelet strategies. Increasing attention has been paid in the last years to the role of vitamin D in atherothrombosis. Therefore, the aim of our study was to evaluate the impact of vitamin D levels on platelet function in patients treated with dual antiplatelet therapy (DAPT). Patients treated with DAPT (ASA and clopidogrel or ticagrelor) after a recent acute coronary syndrome (ACS) or elective PCI were scheduled for platelet function assessment at 30-90 days post-discharge. Platelet function was assessed by whole blood impedance aggregometry (Multiplate®-Roche Diagnostics AG), HRPR was considered for ASPI test values > 862 AU*min (for ASA) and adenosine diphosphate (ADP) test values ≥417 AU*min (for ADP-antagonists). Fasting samples were obtained for main chemistry parameters and vitamin D level assessment. Our population is represented by 503 patients, who were divided according to vitamin D quartiles (≤9.1; 9.2-14.4; 14.5-21.7; >21.7 ng/ml). Lower vitamin D levels related with age (p = 0.04), diabetic status (p = 0.05), and previous coronary surgery (p = 0.007), therapy with beta-blockers and statins (p = 0.01 and p = 0.02). Vitamin D inversely related to the levels of total cholesterol (p = 0.01), triglycerides (p < 0.001), hemoglobin (p = 0.05), and HbA1c (p < 0.001). Significantly higher platelet reactivity was observed after platelet stimulation with ADP (p = 0.01), but not with other platelet activators. The prevalence of HRPR for ASA was low (1.2%) and not conditioned by Vitamin D levels (adjusted OR[95%CI] = 1.56[0.71-3.5], p = 0.27). HRPR with ADP-antagonists was observed in 26% of patients, and the rate increased with lower vitamin D quartiles (37.3% vs 22.2% vs 24.4% vs 20.2%, p = 0.005, adjusted OR[95%CI] = 1.23[1.02-1.49], p = 0.04). An absolute increase in HRPR with lower vitamin D levels was similarly observed among patients receiving ticagrelor (adjusted OR[95% CI] = 1.40[0.95-2.06], p = 0.08), and those on clopidogrel (adjusted OR[95%CI] = 1.31[0.99-1.75], p = 0.06). Thus, lower vitamin D levels are associated with higher platelet reactivity and impaired effectiveness of ADP-antagonists, while not influencing the effectiveness of ASA. Future studies will tell whether vitamin D supplementation can reduce platelet reactivity, overcoming the phenomenon of resistance to antiplatelet agents.

Polymorphisms Associated with Increased Cardiovascular Risk in the General Population do not Predict Acute Events in Hemodialysis Patients.

BACKGROUND: Cardiovascular diseases are the leading cause of morbidity and mortality in hemodialysis patients (HP). The aim of the study was to analyze a series of polymorphisms (known to be associated with increased cardiovascular risk in the general population) in HP, in order to better understand the mechanisms of cardiovascular disease and to find new prevention strategies. METHODS: 102 hemodialysis patients were investigated for polymorphisms associated with increased cardiovascular risk in unselected population (FV Leiden R506Q; FV H1299R; FII G20210A; PAI-1 var 4G/5G; GpIIIA T1565C; FXIII var G/T; ß-FIBRINOGENO var G/A; ACE I/D; AGT var M/T; ATR-1A1166C; APOE T112C; APOE T158C; MTHFR C677T; MTHFR A1298C; CBS 844ins68). RESULTS: No difference was observed in the prevalence of the analysed polymorphisms between HP and Caucasian unselected population, with the exception of FV H1299R, PAI-1 (4G/5G), and Factor XIII V34L, which were significantly higher in HP. However none of the genetic factors analysed was associated in HP with the cardiovascular events (non-fatal and fatal) recorded at the time of recruitment or during the eighteen months -follow up. CONCLUSIONS: In HP, the traditional genetic risk factors for cardiovascular disease are not able to predict acute cardiac events, peripheral vascular events, and cerebral vascular events recorded during a follow up period of eighteen months.

Effect of diabetes mellitus on periprocedural myocardial infarction in patients undergoing coronary stent implantation.

BACKGROUND: Diabetic patients undergoing percutaneous coronary interventions are still regarded as a very high risk category because of an increased platelet reactivity and risk of complications, especially in patients with inadequate glycaemic control. However, although its prognostic effect on long-term outcome is well-defined, still unclear is the effect of diabetes on the risk of periprocedural myocardial infarction in patients undergoing percutaneous coronary interventions, which was therefore the aim of our study. METHODS: Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after nonemergent percutaneous coronary interventions. Periprocedural myocardial infarction was defined as creatine kinase-MB increase by three times the upper limit normal or by 50% of an elevated baseline value, whereas periprocedural myonecrosis as troponin I increase by three times the upper limit normal or 50% of baseline. RESULTS: Of 1311 patients, diabetes mellitus was found in 458 patients (34.9%) and associated with age (p = 0.03), hypertension (p < 0.001), renal failure (p = 0.01), previous MI (p = 0.03), previous coronary revascularization (p < 0.001), higher fasting glycaemia and lower haemoglobin (p < 0.001), more severe coronary disease (p < 0.001), multivessel percutaneous coronary interventions (p = 0.03), coronary calcification (p = 0.003) and in-stent restenosis (p < 0.001) but lower presence of thrombus (p = 0.03). Diabetic patients were receiving significantly more frequent specific pharmacological treatment at admission. Diabetic status did not influence the risk of periprocedural myocardial infarction or periprocedural myonecrosis [adjusted OR(95%CI) = 0.90(0.64-1.27), p = 0.57 and adjusted OR(95%CI) = 0.92(0.70-1.21), p = 0.55]. Amongst diabetic patients, we did not observe any effect of chronic glycaemic control on periprocedural myocardial infarction. CONCLUSIONS: Diabetic status, independent of chronic glycaemic control, is not associated with increased risk of periprocedural myocardial infarction and myonecrosis in patients undergoing percutaneous coronary interventions.

Body Mass Index and Platelet Reactivity During Dual Antiplatelet Therapy With Clopidogrel or Ticagrelor.

INTRODUCTION: Dual antiplatelet therapy (DAPT) is considered essential in clinical management of patients undergoing percutaneous coronary revascularization or acute coronary syndromes. However, the optimal platelet inhibition is not always obtained, with high residual platelet reactivity (HRPR) increasing stent thrombosis and recurrent ischemic events. Aim of this study was to investigate the impact of body mass index (BMI) on platelet reactivity in patients on DAPT. METHODS: We included patients treated with acetylsalycilic acid (ASA) (100-160 mg) and clopidogrel (75 mg) or ticagrelor (90 mg twice a day) for acute coronary syndromes or drug-eluting stent implantation. Platelet reactivity was assessed at 30-90 days postdischarge by multiple-electrode aggregometry. HRPR for adenosine diphosphate (ADP) antagonists was defined as ADP test results >417 AU*min. HRPR for ASA was considered for ASPI test >862 AU*min. RESULTS: Our population is represented by 498 patients, 308 (61.8%) were treated with clopidogrel and 190 (38.2%) with ticagrelor. Overall, higher BMI was related with younger age (P = 0.003), higher prevalence of diabetes mellitus (P < 0.001), hypercholesterolemia (P = 0.017), hypertension (P < 0.001), chronic therapy with angiotensin-receptor blockers (P = 0.019), calcium channel blockers (P = 0.003). Higher values of BMI directly related with hemoglobin (P = 0.02), triglycerides (P < 0.001), glycemia (P = 0.035), HbA1c (P < 0.001), and inversely related with high-density lipoprotein cholesterol (P = 0.01). BMI did not influence the effectiveness of ASA, whereas it was associated to a nonsignificant trend for higher platelet reactivity (r = 0.08, P = 0.08) for ADP antagonists. In fact, 111 patients (22.3%) displayed HRPR at ADP test (>417 AU*min) with no statistically significant difference according to BMI {20.3% vs. 27.1% vs. 25.7%, P = 0.28; adjusted odds ratio [OR] [95% confidence interval (CI)] = 1.19 [0.86-1.64], P = 0.30}. However, results were different when considering separately patients receiving clopidogrel or ticagrelor. In the clopidogrel-treated subgroup, significantly higher ADP-mediated aggregation values were found in patients with higher BMI (r = 0.14, P = 0.023) that emerged as an independent predictor of HRPR with clopidogrel [OR (95% CI), 1.45 (1.01-2.12), P = 0.049]. On the contrary, no impact of BMI was observed in the ticagrelor-treated subgroup for platelet reactivity (r = -0.036, P = 0.62) or the prevalence of HRPR [adjusted OR (95% CI), 0.73 (0.39-1.36), P = 0.32]. CONCLUSIONS: This study shows that among patients treated with DAPT for coronary artery disease, higher BMI is related to increased platelet reactivity and a higher prevalence of HRPR in clopidogrel-treated patients while not significantly influencing the effectiveness of ticagrelor or ASA.

Homocysteine Levels Influence Platelet Reactivity in Coronary Artery Disease Patients Treated With Acetylsalicylic Acid.

BACKGROUND: Suboptimal platelet inhibition with antiplatelet treatments is associated with a severe prognosis in patients with coronary artery disease (CAD), and the identification of its determinants is still challenging. Homocysteine elevation has emerged as a prothrombotic factor, influencing coagulative status and endothelial function and potentially modulating platelet aggregation. We therefore aimed to evaluate the effects of homocysteine (Hcy) levels on platelet reactivity in patients receiving acetylsalicylic acid (ASA) with or without ADP antagonists. METHODS: Patients undergoing coronary angiography and receiving ASA (100-160 mg daily) for >7 days, with or without ADP antagonists, were included. Aggregation tests were performed by multiple electrode aggregometry. Suboptimal platelet inhibition was defined as on-treatment aggregation above the lower limit of normality. RESULTS: Our population is represented by 508 ASA-treated patients, 406 (80.1%) of whom on dual antiplatelet therapy (ASA and ADP antagonists). Hcy levels above the median (15.1 nmol/mL) were associated with male gender (P = 0.04), hypertension (P = 0.004), hypercholesterolemia (P = 0.03), aging, renal failure (P < 0.001, respectively), previous coronary bypass grafting (P = 0.04), therapy with calcium antagonists (P = 0.04) and diuretics (P = 0.001), and multivessel CAD (P = 0.03). Higher Hcy is directly related with serum creatinine and uric acid (P < 0.001). Suboptimal platelet inhibition was found in 16 patients (3.2%) for ASA and for ADP antagonists in 80 patients (19.7%). Hcy levels significantly affected suboptimal response to ASA, but not to ADP-mediated aggregation. In fact, a linear relationship was found between homocysteine and platelet reactivity after stimulation with arachidonic acid (r = 0.14, P = 0.004) and collagen (r = 0.12, P = 0.02), but not with ADP (r = 0.02, P = 0.77). Moreover, after correction for baseline differences, Hcy above the median was confirmed as an independent predictor of impaired ASA response [adjusted odds ratio (95% confidence interval) = 3.7 (1.08-12.4), P = 0.04]. CONCLUSIONS: Among patients with CAD, elevated homocysteine is an independent predictor of suboptimal response to ASA, but not to ADP antagonists.

Platelet Larger Cell Ratio and High-on Treatment Platelet Reactivity During Dual Antiplatelet Therapy.

BACKGROUND: Low response to antiplatelet agents has been associated to an increased risk of thrombotic complications and recurrent ischemic events. Platelet size has been proposed as a potential marker of platelet reactivity. Therefore, the aim of the present study was to evaluate the impact of platelet Larger Cell Ratio (p-LCR) on platelet aggregation and the prevalence of residual high-on treatment platelet reactivity (HRPR) in patients receiving dual antiplatelet therapy (DAPT) after a recent acute coronary syndrome or coronary revascularization. METHODS: Patients treated with DAPT (ASA and clopidogrel or ticagrelor) were scheduled for platelet function assessment at 30-90 days post-discharge. HRPR was considered for ASPI test >862 AU*min (for ASA) or ADP test values ≥417 AU*min (for ADP-antagonists) using impedance aggregometry. RESULTS: Our population consisted of 530 patients receiving DAPT, who were divided in tertiles according to values of p-LCR (< 27.6; 27.6-34.7; ≥34.7 l). p-LCR was related with use of beta-blockers (p = 0.02) and statins (p = 0.002), and inversely with acute presentation (p = 0.05). Higher platelet count (p < 0.001) and haemoglobin levels (p = 0.001) were observed in higher p-LCR tertiles. The prevalence of HRPR for ASA was low and not significantly different across tertiles of p-LCR (1.1 vs 1.1 vs 1.7%, p = 0.66; adjusted OR[95%CI] = 1.68[0.66-4.29], p = 0.27). Moreover, p-LCR did not influence the occurrence of HRPR for ADP-antagonists (24.4% vs 20.9% vs 25.6 %%, p = 0.80, adjusted OR[95%CI] = 0.88[0.67-1.17], p = 0.38) and similar results were obtained when considering separately patients receiving clopidogrel (adjusted OR[95%CI] = 1.21[0.86-1.69], p = 0.29) or ticagrelor (adjusted OR[95%CI] = 1.17[0.69-2], p = 0.56). CONCLUSION: In patients receiving DAPT for coronary artery disease, p-LCR does not impact platelet reactivity. Larger platelets did not influence the prevalence of high-on treatment platelet reactivity with the antiplatelet agents ASA, clopidogrel or ticagrelor.

Platelet-larger cell ratio and the risk of periprocedural myocardial infarction after percutaneous coronary revascularization.

Periprocedural myocardial infarction (PMI) represents a frequent complication in patients undergoing percutaneous coronary revascularization. Despite great attention focused on pharmacological prevention of periprocedural damage, very little is known about using biomarkers to potentially predict the risk of PMI. Larger platelets have been associated with enhanced reactivity, increased cardiovascular risk, and higher rates of complications after coronary stenting. The platelet-larger cell ratio (P-LCR) identifies the largest-sized fraction of platelets, the proportion potentially more closely related to thrombotic events. The present study evaluated the relationship between P-LCR and PMI. We included 1,285 patients undergoing PCI. Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after PCI. Periprocedural myonecrosis was defined as troponin I increase by three times the upper limit of normal (ULN) or by 50 % of an elevated baseline value, whereas PMI was defined as an increase in creatine kinase MB by 3 × ULN or 50 % of baseline. We grouped patients according to tertile values of P-LCR (<27.5; ≥35.1). Higher P-LCR was associated with age (P = 0.01), diabetes (P = 0.001), previous cerebrovascular accidents (P = 0.007), therapy with statins (P < 0.001), angiotensin receptor blockers (P < 0.001), aspirin (P = 0.002), and nitrates (P = 0.01). P-LCR was related to hemoglobin levels (P < 0.001), and inversely related to platelet count (P < 0.001) and glycemia (P = 0.05). Patients with higher P-LCR had a lower presence of coronary thrombus (P = 0.003). Higher P-LCR values did not increase the risk of PMI (P = 0.10; adjusted odds ratio (OR) (95 % confidence interval (CI)) = 0.97 (0.69-1.38)), P = 0.89) or periprocedural myonecrosis (P = 0.96; adjusted OR (95 % CI) = 1.003 (0.76-1.32), P = 0.99). Results were confirmed even in higher-risk subgroups of patients. P-LCR does not increase the risk of periprocedural myocardial infarction and myonecrosis in patients undergoing coronary stenting.

Platelet distribution width and the risk of periprocedural myocardial infarction in patients undergoing percutaneous coronary intervention.

Periprocedural myocardial infarction (PMI) still occurs in a large amount of percutaneous coronary interventions (PCI), mainly due to increased platelet activation. Platelet size has been suggested as an indicator of enhanced reactivity and platelet distribution width (PDW) could reflect morphologic changes in platelets, therefore affecting their function and potentially increasing the risk of complications after coronary stenting. Aim of the present study was to evaluate the relationship between PDW and PMI. We included 1,300 consecutive patients undergoing PCI. Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after PCI. Periprocedural myonecrosis was defined as troponin I increase by three times the ULN or by 50 % of an elevated baseline value, whereas PMI as CKMB increase by three times the ULN or 50 % of baseline. We grouped patients according to tertiles values of PDW (<12.1; ≥13.9). Higher PDW was associated with age (p = 0.03), diabetes (p < 0.001), previous cerebrovascular accidents (p = 0.04), therapy with statins (p = 0.001) and ARBs (p < 0.001), ASA (p = 0.02), nitrates (p = 0.006), calcium antagonists (p = 0.05) and lower pre-procedural clopidogrel bolus (p = 0.005). PDW related with haemoglobin levels (p < 0.001), while inversely to platelet count (p < 0.001) and glycaemia (p = 0.003). Patients with larger PDW had lower presence of coronary thrombus (p < 0.001), higher rate of coronary calcifications (p = 0.02), higher stenting rate (p = 0.03) and lower rate of distal embolization (p = 0.03). Larger PDW did not increase risk of PMI (p = 0.11; adjusted OR [95 % CI] = 0.94 [0.78-1.1], p = 0.55) or periprocedural myonecrosis (p = 0.73; adjusted OR [95 % CI] = 0.95 [0.82-1.1], p = 0.51). Results were confirmed even in higher-risk subgroups of patients. In patients undergoing coronary stenting, PDW does not increase the risk of periprocedural MI and therefore should not be considered a risk factor for thrombotic periprocedural complications after PCI.

An observational study of Venlafaxine and CYP2D6 in clinical practice.

BACKGROUND: Venlafaxine (V) is a serotonin-norepinephrine selective reuptake inhibitor, mainly metabolized by cytochrome P4502D6 (CYP2D6). CYP2D6 polymorphisms result in a variety of phenotypes: poor (PMs), intermediate (IMs), extensive (EMs), and ultrarapid metabolizers (UMs). PMs usually show poor tolerance to drugs metabolized by CYP2D6, while UMs need greater doses. The aim of this study was to evaluate the impact of CYP2D6 genotype on V dosage, therapeutic response, and side effects in a clinical outpatient setting. METHODS: 47 patients with Major Depressive Disorder, treated with V 75 - 300 mg/day, underwent CYP2D6 genotyping using the INFINITI-CYP2D6 assay. Duration of treatment and clinical outcome (Clinical Global Impression [CGI] effectiveness index) were assessed. RESULTS: CGI assessment was performed after 6 weeks, 6 months, and 1 year of treatment with a V median dose of 150 mg/day. CYP2D6 genotyping resulted in 1 PM, 3 IMs, 42 EMs, and 1 UM. The UM took the greatest V dose (375 mg) without side effects; IMs/PMs took moderate/high doses of V (150 - 300 mg) without adverse effects; EMs displayed high response variability. CONCLUSIONS: PM/IM patients responded to V differently than expected according to genotype. However, the UM patient responded to a dosage higher than the usual therapeutic range and without developing side effects, suggesting an association between CYP2D6 gene duplication and the therapeutic efficacy of venlafaxine. The CYP2D6 genotyping may thus provide clinicians with a potential explanation for those patients requiring greater doses of CYP2D6 substrates in order to obtain the same therapeutic efficacy.

Routine coagulation tests are not useful as a screening tool for the FII G20210A polymorphism.

BACKGROUND: The identification of prothrombin G20210A polymorphism (PT20210) is normally included in the thrombophilia laboratory panel and evaluated by DNA-based molecular analysis. To date, a routine coagulation test that helps to identify PT20210 carriers has not been set, in contrast to the FV Leiden mutation, for which a functional coagulation test, the Activated Protein C Resistance test (APCR), is available as a screening tool. More- over the molecular tests are expensive and are used inappropriately. The aim of the study is to characterize the effects of the prothrombin G20210A mutation on routine clotting assays in order to identify, if any, coagulation tests that can be used as a first-line cost-effective assay for prothrombin G20210A polymorphism. METHODS: Our cohort consisted of 80 PT20210 polymorphism carriers and 82 age and gender matched controls. All subjects were investigated for PT-INR, aPTT, dRVVT, FII (%), and Endogenous Thrombin Potential (EPT) parameters. RESULTS: In heterozygotes and wild-type, PT, aPTT, and dRVVT values were not significantly different. The plasma activity of Factor II (%), AUC TG (%), and C max (%) of EPT were significantly higher in heterozygotes than in controls (p < 0.0001, Mann-Whitney test). In the absence of oral anticoagulant therapy and/or heparin, lupus anticoagulants, and liver disease, the discriminating abilities of the FII, AUC TG, and C max (%) to separate properly the study population into carriers and controls were equal to 0.99 (95% CI 0.98 to 1.00); 0.97 (95% CI 0.94 to 0.99), and 0.84 (95% CI 0.77 to 0.90), respectively. CONCLUSIONS: All routine clotting assays performed in the present work are not useful as a screening tool for the G20210A prothrombin gene allele in a general population. Definitely, to date, the exclusive possible approach to identify the PT20210 mutation is molecular genetic testing, but unfortunately it is used inappropriately, contributing significantly to an uncontrolled waste of resources. It is mandatory to restrict the genetic thrombophilia test ordering to when it is actually recommended by the guidelines and to educate clinicians on the waste and danger of over-testing, particularly genetic tests, taking into account the fact that the PT20210 polymorphism is extremely variable (0.7 to 8% in Europe; 1.3-5% in the USA).

Neonatal screening for sickle cell disease and other hemoglobinopathies in "the changing Europe".

BACKGROUND: Inherited hemoglobin disorders (sickle-cell disorders and thalassaemias) represent an increasing global health problem. The early detection of sickle cell disease allows counselling for family members about disease management and future reproductive decisions. The aim of the present study was to estimate the birth prevalence of hemoglobinopathies in newborns of Italian couples and couples of immigrants from endemic areas living in an urban area of northern Italy in order to assess the opportunity of implementing a neonatal screening programme for hemoglobin disorders. METHODS: Inclusion criteria were infants with at least one of the parents from high risk areas of hemoglobinopathies (Po delta and Sardinia, Italy; Mediterranean area; sub-Saharan Africa; Brazil; Asia) or a positive family history for hemoglobinopathies. The number of infants included in the present study was 337: 13.8% out of 2447 children born at Azienda Ospedaliera Universitaria (AOU) "Maggiore della Carità", Novara, Italy, from 31 December 2012 to 31 January 2014 and 47.6% of 710 infants with at least one foreign parent. RESULTS: 232 infants were wild-type (68.8%) for hemoglobin variants; 48 subjects (14.2%) had no hemoglobin variants, but we could not exclude the presence of a thalassemia trait (Hb A < 15%): a further monitoring of hemoglobin electrophoresis at 6 months was therefore recommended. 20 infants (5.9%) had Hb S (7.7% ± 3 of the total hemoglobin; range 3.5 - 13) and were diagnosed as Hb S carriers and 2 infants (0.6%) had Hb C (7.8% and 12.1% of the total hemoglobin, respectively) and were diagnosed as Hb C carriers. CONCLUSIONS: Based on our results, we can conclude that: (i) the sickle-cell disorder (Hb S) is relatively high in our territory, with a heterozygous frequency in infants at risk of 5.9%; (ii) the neonatal screening for hemoglobin disorders appears to be a valid, easy to perform test, which allows an early diagnosis and timely payment of hemoglobinopathies in populations at risk.

Does asymmetric dimethylarginine (ADMA) plasma concentration predict esophageal varices in patients with cirrhosis?

BACKGROUND: In previous studies elevated Asymmetric NG, NG - dimethylarginine (ADMA) plasma levels, an endogenous nitric oxide synthase inhibitor, correlated with the severity of hepatic venous pressure gradient measurement, both in peripheral and in hepatic veins. The aim of this study was to explore whether elevated ADMA plasma levels were able to predict the presence of esophageal varices (EV) and/or large EV in patients with cirrhosis. METHODS: 74 cirrhotic patients who had undergone elective upper gastrointestinal endoscopy in order to assess the presence of portal hypertension and predictors of EV and/or large EV. ADMA levels were assayed by an ELISA test (Immundiagnostik AG, Germany). RESULTS: 53 patients had EV (26/53 had large EV). Univariate analysis of low hemoglobin (p = 0.045), PT-INR (p = 0.003), albumin (p = 0.024), bilirubin (p = 0.036), Child-Pugh score (p = 0.026), and ascites (p = 0.036) predicted the presence of EV. Multivariate analysis predicted EV for only PT-INR. The presence of large EV was predicted with univariate analysis of ADMA plasma levels (p = 0.013), low hemoglobin (p < 0.001), PT-INR (p = 0.001), albumin (p = 0.001), bilirubin (p = 0.026), Child-Pugh score (p < 0.001), ascites (p = 0.004). Sensitivity, specificity, predictive positive and negative values of ADMA plasma level > 0.5 micromol/L(-1) in predicting large EV were 0.69 (95% CI 0.53 - 0.82), 0.51 (95% CI 0.40 - 0.62), 0.43 (95% CI 0.31 - 0.56), 0.76 (95% CI 0.62 - 0.86), while the area under the ROC curve was 0.65 (95% CI 0.51 - 0.79). CONCLUSIONS: ADMA plasma levels were increased in cirrhotics with more advanced liver failure but did not prove to be a useful clinical tool for predicting the presence of esophageal varices or large esophageal varices.

Lack of association between GRIA1 polymorphisms and haplotypes with migraine without aura or response to triptans.

The present study was designed to replicate previous findings reporting a significant association between the rs548294 polymorphism at the glutamate receptor subunit GluR1 gene (GRIA1) and migraine without aura, either as a single marker or in haplotype combination with rs2195450. In addition, the role of GRIA1 polymorphisms and haplotypes was evaluated in migraine patients without aura as predictive factors for consistency in headache response to triptans. Analysis of rs548294 and rs2195450 polymorphisms of GRIA1 was conducted by Real-time PCR allelic discrimination assay in 186 migraine patients without aura and 312 healthy controls, respectively. In the logistic regression analysis adjusted for gender and age, genotype and haplotype frequencies for the two polymorphisms did not significantly differ between migraine patients without aura and controls. In addition, no evidence of association was found between GRIA1 polymorphisms/haplotypes and consistent response to triptans. This study failed to replicate previously reported association between GRIA1 rs548294 and migraine without aura, either as single marker or when analyzed in haplotype combination with rs2195450. In addition, no evidence was found for a relevant role of GRIA1 polymorphisms and haplotypes as modulating factors of headache response to triptans.

Levosimendan protection against kidney ischemia/reperfusion injuries in anesthetized pigs.

Ischemia/reperfusion (I/R) injury is an important cause of acute renal failure because of oxidative, inflammatory, and apoptotic mechanisms. The aim of the present study was to examine any possible protective effects of levosimendan in an in vivo pig model of renal I/R injury. In 40 anesthetized pigs (eight groups of five pigs each), I/R was induced by clamping-reopening the left renal artery. During ischemia, in three groups of pigs, levosimendan and the multiorgan preservation solution Custodiol, alone or in combination with levosimendan, were infused in the renal artery. In two other groups of animals, levosimendan in combination with Custodiol was administered after the intrarenal nitric-oxide (NO) synthase blocker N(ω)-nitro-L-arginine methyl ester (L-NAME) or the mitochondrial ATP-sensitive K(+) channel (K(ATP) channel) inhibitor 5-hydroxydecanoate (5-HD). In the other animals, saline, L-NAME, or 5-HD were administered alone. Throughout the experiments, urinary N-acetyl-ß-glucosaminidase (NAG) release was measured, and renal function was assessed. Moreover, renal biopsy samples were taken for the detection of apoptosis and tissue peroxidation. In pigs treated with levosimendan or the combination of levosimendan and Custodiol, NAG, peroxidation, and apoptotic markers were lower than in animals treated with Custodiol alone. In addition, renal function was better preserved, and cell survival and antioxidant systems were more activated. All beneficial effects were prevented by L-NAME and 5-HD. In conclusion, levosimendan alone or in combination with Custodiol exerted better protection against renal I/R injuries than Custodiol alone through antioxidant, antiapoptotic, and prosurvival actions depending on mitochondrial K(ATP) channels and NO-related mechanisms.