48 research outputs found

    Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

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    Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

    Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

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    Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

    Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

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    Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p

    Effect of alirocumab on mortality after acute coronary syndromes. An analysis of the ODYSSEY OUTCOMES randomized clinical trial

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    Background: Previous trials of PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitors demonstrated reductions in major adverse cardiovascular events, but not death. We assessed the effects of alirocumab on death after index acute coronary syndrome. Methods: ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) was a double-blind, randomized comparison of alirocumab or placebo in 18 924 patients who had an ACS 1 to 12 months previously and elevated atherogenic lipoproteins despite intensive statin therapy. Alirocumab dose was blindly titrated to target achieved low-density lipoprotein cholesterol (LDL-C) between 25 and 50 mg/dL. We examined the effects of treatment on all-cause death and its components, cardiovascular and noncardiovascular death, with log-rank testing. Joint semiparametric models tested associations between nonfatal cardiovascular events and cardiovascular or noncardiovascular death. Results: Median follow-up was 2.8 years. Death occurred in 334 (3.5%) and 392 (4.1%) patients, respectively, in the alirocumab and placebo groups (hazard ratio [HR], 0.85; 95% CI, 0.73 to 0.98; P=0.03, nominal P value). This resulted from nonsignificantly fewer cardiovascular (240 [2.5%] vs 271 [2.9%]; HR, 0.88; 95% CI, 0.74 to 1.05; P=0.15) and noncardiovascular (94 [1.0%] vs 121 [1.3%]; HR, 0.77; 95% CI, 0.59 to 1.01; P=0.06) deaths with alirocumab. In a prespecified analysis of 8242 patients eligible for ≥3 years follow-up, alirocumab reduced death (HR, 0.78; 95% CI, 0.65 to 0.94; P=0.01). Patients with nonfatal cardiovascular events were at increased risk for cardiovascular and noncardiovascular deaths (P<0.0001 for the associations). Alirocumab reduced total nonfatal cardiovascular events (P<0.001) and thereby may have attenuated the number of cardiovascular and noncardiovascular deaths. A post hoc analysis found that, compared to patients with lower LDL-C, patients with baseline LDL-C ≥100 mg/dL (2.59 mmol/L) had a greater absolute risk of death and a larger mortality benefit from alirocumab (HR, 0.71; 95% CI, 0.56 to 0.90; Pinteraction=0.007). In the alirocumab group, all-cause death declined wit h achieved LDL-C at 4 months of treatment, to a level of approximately 30 mg/dL (adjusted P=0.017 for linear trend). Conclusions: Alirocumab added to intensive statin therapy has the potential to reduce death after acute coronary syndrome, particularly if treatment is maintained for ≥3 years, if baseline LDL-C is ≥100 mg/dL, or if achieved LDL-C is low. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01663402

    P2466The impact of circumferential pulmonary vein isolation on global and regional left atrial function in patients with paroxysmal atrial fibrillation

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    Abstract Introduction The effect of circumferential pulmonary vein isolation (PVI) for atrial fibrillation (AF) on left atrial (LA) function has not been well defined. Purpose The aim of this study was to evaluate the immediate impact of ablation on parameters of global and regional LA function using intracardiac echocardiography (ICE) Methods We studied 26 consecutive patients (age 56±10 years, 19 men) with paroxysmal AF using ICE before and immediately after circumferential PVI. All pulmonary veins were isolated in all patients. ICE measurements included LA fractional area shortening, peak A wave on transmitral Doppler flow, peak emptying velocity on the left atrial appendage (LAA) Doppler flow, as well as tissue Doppler myocardial velocities at the level of the posterior LA wall, interatrial septum, and lateral wall, which were used as parameters of regional LA function. Results The mean radiofrequency ablation time was 37±22min. Post ablation there was a significant reduction of the LA fractional area shortening from 27±8% to 22±6% (p&lt;0.01). The tissue Doppler velocity of atrial contraction at the posterior wall decreased significantly post ablation: from 8.9±1.8 cm/s to 6.9±1.4 cm/s (p&lt;0.01). There were no significant differences between the pre and post ablation values for tissue Doppler velocities at the level of the interatrial septum or LA lateral wall. The post ablation peak transmitral A wave and peak LAA Doppler velocities did not differ significantly from the pre ablation values. Conclusion In patients with paroxysmal atrial fibrillation, circumferential PVI results in an immediate decrease in LA function without a significant change in LAA function. </jats:sec

    P713 An incidental finding of a completely thrombosed left ventricular pseudoaneurysm: what is the next step?

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    Abstract Introduction Left ventricular pseudoaneurysm is a rare complication of myocardial infarction. It is the result of ventricular rupture contained by the pericardial adhesions or thrombus. Although echocardiography is suitable as the initial method for diagnosis, multimodality imaging is often required in order to further characterize the pseudoaneurysm morphology and to plan the treatment. Case report A 56-year-old male patient with an old inferior myocardial infarction treated conservatively 6 years ago, was admitted in our department for atypical left laterothoracic pain. Three months before he had the same symptoms and an unexplained paracardiac mass was incidentally diagnosed by transthoracic echocardiography. At that time, he was evaluated by coronary angiography which showed no epicardial coronary artery stenosis. During admission, the ECG showed sinus rhythm, inferior myocardial scarring and right bundle branch block. The laboratory tests revealed cardiac enzymes within normal range, increased D-dimeri and elevated inflammatory markers. The echocardiography showed a nondilated left ventricle (LV) with preserved ejection fraction and akinesia of the inferolateral(IL) LV wall. Attached to the basal IL LV wall, an extensive mass was documented with an echogenic appearance and no color Doppler flow, suggesting a thrombosed pseudoaneurysm. A contrast enhanced computed tomography (CT) scan confirmed the diagnosis, but it was not able to establish whether the pseudoaneurysm was partially or completely thrombosed. For a more accurate morphologic and tissue characterization, a cardiac magnetic resonance imaging(CMR) was subsequently performed, that confirmed the presence of a completely thrombosed pseudoaneurysm, measuring 82x38mm. In this case, a conservative approach was initially suggested by the completely thrombosed chronic pseudoaneurysm (older than 3months and with no Doppler color flow). However, according to the literature a surgical approach should be considered when the pseudoaneurysm dimension is larger than 3 cm. Since the patient refused the surgical intervention, medical treatment was initiated with anticoagulants due to the high embolic risk, betablockers and angiotensin-receptor antagonists to maintain the blood pressure less than 120/80mmHg. At 1 month, his condition was stable. He will be reevaluated in 3 months, to monitor the possible pseudoaneurysm expansion. According to our knowledge, this is the first case of a completely thrombosed pseudoaneurysm described in the literature. Its echocardiographic, CT and CMR appearance is important for the differential diagnosis of all paracardiac masses (tumors, hiatus hernias, etc). Conclusion Completely thrombosed left ventricle pseudoaneurysm remains a challenging diagnosis since its echocardiographic appearance is atypical. Cardiac magnetic resonance imaging has a higher diagnostic yield and can provide important information that may influence the course of treatment. Abstract P713 Figure. LV Pseudoaneurysm-multimodality imaging </jats:sec

    P338 The road to zero-fluoroscopy catheter ablation in recurrent paroxysmal atrial fibrillation using ICE: training, learning, getting closer

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    Abstract INTRODUCTION Catheter ablation is the treatment of choice for patients with recurrent paroxysmal atrial fibrillation (AF) in which antiarrhythmic drug therapy has failed to maintain sinus rhythm. Since its first introduction, intracardiac echocardiography (ICE) has proved to increase the efficacy and reduce complications in AF catheter ablation. One of the main advantages of ICE in the electrophysiology laboratory is the reduction of radiation exposure, for both the patient and the physician. Multiple recent studies have shown the feasibility and safety of zero or near-zero fluoroscopy AF ablation, including transseptal puncture, and outlined the importance of using ICE under the support of 3D mapping systems in reducing radiation exposure. PURPOSE The aim of this study was to show whether the use of ICE reduced the radiation exposure and total procedure time in recurrent paroxysmal AF patients undergoing radiofrequency catheter ablation. METHODS Forty patients that undergone radiofrequency catheter ablation for recurrent paroxysmal AF between January 2018 and May 2019 were included. They were divided in two groups: Group 1 – 20 patients in which ICE was performed and Group 2 – 20 patients in which ablation was performed without ICE guidance. We compared the total ablation time and fluoroscopy dose and time between the two groups. The total ablation time was defined as the time from the groin puncture until the withdrawal of all catheters. RESULTS Among the 40 patients included, 28 were men (70%) and the mean age was 57 years old. The mean procedure time was similar between the two groups (175 ± 52.0 for group 1 and 193 ± 49.9 for group 2, p = 0.33). The difference between the two groups was observed in fluoroscopy dose (9914.13 ± 5018.14 vs. 14561.43 ± 7446.1, p = 0.02) and time (26.04 ± 12.5 vs. 40.52 ± 12.6, p = 0.001). We found that in both groups higher fluoroscopy dose was correlated with higher fluoroscopy time (R = 0.74, p = 0.0001 vs. R = 0.57, p = 0.008) and higher total procedure time (R = 0.63, p = 0.002 vs. R = 0.46, p = 0.03). Furthermore, there was also a correlation between higher fluoroscopy dose and time (R = 0.59, p = 0.005 vs. R = 0.58, p = 0.006). No severe procedure-related complications were recorded. CONCLUSIONS This study shows that the use of ICE for recurrent paroxysmal AF catheter ablation reduces radiation exposure by lowering the fluoroscopy dose and the time of exposure. As a result, by increasing the training and learning curve in low-experienced centers it may finally get us closer to the ideal zero or near-zero fluoroscopy ablation. Abstract P338 Figure. ICE-guided transseptal puncture </jats:sec

    Lipoprotein(a) and Benefit of PCSK9 Inhibition in Patients With Nominally Controlled LDL Cholesterol

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    Background: Guidelines recommend nonstatin lipid-lowering agents in patients at very high risk for major adverse cardiovascular events (MACE) if low-density lipoprotein cholesterol (LDL-C) remains ≥70 mg/dL on maximum tolerated statin treatment. It is uncertain if this approach benefits patients with LDL-C near 70 mg/dL. Lipoprotein(a) levels may influence residual risk. Objectives: In a post hoc analysis of the ODYSSEY Outcomes (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) trial, the authors evaluated the benefit of adding the proprotein subtilisin/kexin type 9 inhibitor alirocumab to optimized statin treatment in patients with LDL-C levels near 70 mg/dL. Effects were evaluated according to concurrent lipoprotein(a) levels. Methods: ODYSSEY Outcomes compared alirocumab with placebo in 18,924 patients with recent acute coronary syndromes receiving optimized statin treatment. In 4,351 patients (23.0%), screening or randomization LDL-C was 13.7 mg/dL or ≤13.7 mg/dL; corresponding adjusted treatment hazard ratios were 0.82 (95% CI: 0.72-0.92) and 0.89 (95% CI: 0.75-1.06), with Pinteraction = 0.43. Conclusions: In patients with recent acute coronary syndromes and LDL-C near 70 mg/dL on optimized statin therapy, proprotein subtilisin/kexin type 9 inhibition provides incremental clinical benefit only when lipoprotein(a) concentration is at least mildly elevated. (ODYSSEY Outcomes: Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab; NCT01663402

    Alirocumab and cardiovascular outcomes after acute coronary syndrome

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    BACKGROUND Patients who have had an acute coronary syndrome are at high risk for recurrent ischemic cardiovascular events. We sought to determine whether alirocumab, a human monoclonal antibody to proprotein convertase subtilisin-kexin type 9 (PCSK9), would improve cardiovascular outcomes after an acute coronary syndrome in patients receiving high-intensity statin therapy. METHODS We conducted a multicenter, randomized, double-blind, placebo-controlled trial involving 18,924 patients who had an acute coronary syndrome 1 to 12 months earlier, had a low-density lipoprotein (LDL) cholesterol level of at least 70 mg per deciliter (1.8 mmol per liter), a non-highdensity lipoprotein cholesterol level of at least 100 mg per deciliter (2.6 mmol per liter), or an apolipoprotein B level of at least 80 mg per deciliter, and were receiving statin therapy at a high-intensity dose or at the maximum tolerated dose. Patients were randomly assigned to receive alirocumab subcutaneously at a dose of 75 mg (9462 patients) or matching placebo (9462 patients) every 2 weeks. The dose of alirocumab was adjusted under blinded conditions to target an LDL cholesterol level of 25 to 50 mg per deciliter (0.6 to 1.3 mmol per liter). The primary end point was a composite of death from coronary heart disease, nonfatal myocardial infarction, fatal or nonfatal ischemic stroke, or unstable angina requiring hospitalization. RESULTS The median duration of follow-up was 2.8 years. A composite primary end-point event occurred in 903 patients (9.5%) in the alirocumab group and in 1052 patients (11.1%) in the placebo group (hazard ratio, 0.85; 95% confidence interval [CI], 0.78 to 0.93; P<0.001). A total of 334 patients (3.5%) in the alirocumab group and 392 patients (4.1%) in the placebo group died (hazard ratio, 0.85; 95% CI, 0.73 to 0.98). The absolute benefit of alirocumab with respect to the composite primary end point was greater among patients who had a baseline LDL cholesterol level of 100 mg or more per deciliter than among patients who had a lower baseline level. The incidence of adverse events was similar in the two groups, with the exception of local injection-site reactions (3.8% in the alirocumab group vs. 2.1% in the placebo group). CONCLUSIONS Among patients who had a previous acute coronary syndrome and who were receiving highintensity statin therapy, the risk of recurrent ischemic cardiovascular events was lower among those who received alirocumab than among those who received placebo

    Effects of alirocumab on cardiovascular and metabolic outcomes after acute coronary syndrome in patients with or without diabetes: a prespecified analysis of the ODYSSEY OUTCOMES randomised controlled trial

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    Background: After acute coronary syndrome, diabetes conveys an excess risk of ischaemic cardiovascular events. A reduction in mean LDL cholesterol to 1·4–1·8 mmol/L with ezetimibe or statins reduces cardiovascular events in patients with an acute coronary syndrome and diabetes. However, the efficacy and safety of further reduction in LDL cholesterol with an inhibitor of proprotein convertase subtilisin/kexin type 9 (PCSK9) after acute coronary syndrome is unknown. We aimed to explore this issue in a prespecified analysis of the ODYSSEY OUTCOMES trial of the PCSK9 inhibitor alirocumab, assessing its effects on cardiovascular outcomes by baseline glycaemic status, while also assessing its effects on glycaemic measures including risk of new-onset diabetes. Methods: ODYSSEY OUTCOMES was a randomised, double-blind, placebo-controlled trial, done at 1315 sites in 57 countries, that compared alirocumab with placebo in patients who had been admitted to hospital with an acute coronary syndrome (myocardial infarction or unstable angina) 1–12 months before randomisation and who had raised concentrations of atherogenic lipoproteins despite use of high-intensity statins. Patients were randomly assigned (1:1) to receive alirocumab or placebo every 2 weeks; randomisation was stratified by country and was done centrally with an interactive voice-response or web-response system. Alirocumab was titrated to target LDL cholesterol concentrations of 0·65–1·30 mmol/L. In this prespecified analysis, we investigated the effect of alirocumab on cardiovascular events by glycaemic status at baseline (diabetes, prediabetes, or normoglycaemia)—defined on the basis of patient history, review of medical records, or baseline HbA1c or fasting serum glucose—and risk of new-onset diabetes among those without diabetes at baseline. The primary endpoint was a composite of death from coronary heart disease, non-fatal myocardial infarction, fatal or non-fatal ischaemic stroke, or unstable angina requiring hospital admission. ODYSSEY OUTCOMES is registered with ClinicalTrials.gov, number NCT01663402. Findings: At study baseline, 5444 patients (28·8%) had diabetes, 8246 (43·6%) had prediabetes, and 5234 (27·7%) had normoglycaemia. There were no significant differences across glycaemic categories in median LDL cholesterol at baseline (2·20–2·28 mmol/L), after 4 months' treatment with alirocumab (0·80 mmol/L), or after 4 months' treatment with placebo (2·25–2·28 mmol/L). In the placebo group, the incidence of the primary endpoint over a median of 2·8 years was greater in patients with diabetes (16·4%) than in those with prediabetes (9·2%) or normoglycaemia (8·5%); hazard ratio (HR) for diabetes versus normoglycaemia 2·09 (95% CI 1·78–2·46, p<0·0001) and for diabetes versus prediabetes 1·90 (1·65–2·17, p<0·0001). Alirocumab resulted in similar relative reductions in the incidence of the primary endpoint in each glycaemic category, but a greater absolute reduction in the incidence of the primary endpoint in patients with diabetes (2·3%, 95% CI 0·4 to 4·2) than in those with prediabetes (1·2%, 0·0 to 2·4) or normoglycaemia (1·2%, −0·3 to 2·7; absolute risk reduction pinteraction=0·0019). Among patients without diabetes at baseline, 676 (10·1%) developed diabetes in the placebo group, compared with 648 (9·6%) in the alirocumab group; alirocumab did not increase the risk of new-onset diabetes (HR 1·00, 95% CI 0·89–1·11). HRs were 0·97 (95% CI 0·87–1·09) for patients with prediabetes and 1·30 (95% CI 0·93–1·81) for those with normoglycaemia (pinteraction=0·11). Interpretation: After a recent acute coronary syndrome, alirocumab treatment targeting an LDL cholesterol concentration of 0·65–1·30 mmol/L produced about twice the absolute reduction in cardiovascular events among patients with diabetes as in those without diabetes. Alirocumab treatment did not increase the risk of new-onset diabetes. Funding: Sanofi and Regeneron Pharmaceuticals
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