Clinical efficacy and safety outcomes of bempedoic acid for LDL-C lowering therapy in patients at high cardiovascular risk: a systematic review and meta-analysis

Background

Bempedoic acid (BA) is a novel oral low-density lipoprotein cholestrol (LDL-C) lowering drug. Its efficacy and safety for clinical outcomes in high cardiovascular risk patients remains unknown.

Objectives and methods

A systematic review was performed and randomized controlled trials (RCTs) of BA vs. placebo in high cardiovascular risk patients reporting clinical efficacy and safety outcomes were included in a meta-analysis. Cumulative odds ratios (OR) and mean differences with 95% confidence intervals (CI) were reported as summary statistics.

Results

Six RCTs with a total of 3,956 patients and follow-ups of four to 52 weeks were identified. There was no difference in MACE (OR 0.84; CI 0.61, 1.15), all-cause mortality (OR 2.37; CI 0.80, 6.99) and cardiovascular mortality (OR 1.66; CI 0.45, 6.04) for BA vs. placebo. BA showed beneficial trends for nonfatal myocardial infarction (OR 0.57; CI 0.32, 1.00) and was associated with a lower risk of new-onset or worsening of diabetes mellitus (OR 0.68; CI 0.49, 0.94) and non-coronary revascularization (OR 0.41; CI 0.18, 0.95), but higher risk of gout (OR 3.29; CI 1.28, 8.46) and a trend for worsening of renal function (OR 4.24; CI 0.98, 18.39) and muscular disorders (OR 2.60; CI 1.15, 5.91).

Conclusion

Bempedoic acid in high cardiovascular risk patients showed no significant effects on major cardiovascular outcomes in short-term follow-up. Unfavourable effects on muscular disorders, renal function and the incidence of gout sound a note of caution. Hence, further studies with longer-term follow-up are needed to clarify the risk/benefit ratio of this novel therapy.

Funding Acknowledgement

Type of funding sources: None.

Wildlife conservation in a fragmented landscape: the Eurasian red squirrel on the Isle of Wight

Island populations may have a higher extinction risk due to reduced genetic diversity and need to be managed effectively in order to reduce the risk of biodiversity loss. The Eurasian red squirrels (Sciurus vulgaris) in the south of England only survive on three islands (the Isle of Wight, Brownsea and Furzey islands), with the Isle of Wight harbouring the largest population in the region. Fourteen microsatellites were used to determine the genetic structure of red squirrel populations on the Isle of Wight, as well as their relatedness to other populations of the species. Our results demonstrated that squirrels on these islands were less genetically diverse than those in Continental mainland populations, as would be expected. It also confirmed previous results from mitochondrial DNA which indicated that the squirrels on the Isle of Wight were relatively closely related to Brownsea island squirrels in the south of England. Importantly, our findings showed that genetic mixing between squirrels in the east and west of the Isle of Wight was very limited. Given the potential deleterious effects of small population size on genetic health, landscape management to encourage dispersal of squirrels between these populations should be a priority.

Introduction and spread of variegated squirrel bornavirus 1 (VSBV-1) between exotic squirrels and spill-over infections to humans in Germany

The variegated squirrel bornavirus 1 (VSBV-1) is a recently discovered emerging viral pathogen which causes severe and eventually fatal encephalitis in humans after contact to exotic squirrels in private holdings and zoological gardens. Understanding the VSBV-1 epidemiology is crucial to develop, implement, and maintain surveillance strategies for the detection and control of animal and human infections. Based on a newly detected human encephalitis case in a zoological garden, epidemiological squirrel trade investigations and molecular phylogeny analyses of VSBV-1 with temporal and spatial resolution were conducted. Phylogenetic analyses indicated a recent emergence of VSBV-1 in European squirrel holdings and several animal–animal and animal–human spill-over infections. Virus phylogeny linked to squirrel trade analysis showed the introduction of a common ancestor of the known current VSBV-1 isolates into captive exotic squirrels in Germany, most likely by Prevost’s squirrels (Callosciurus prevostii). The links of the animal trade between private breeders and zoos, the likely introduction pathway of VSBV-1 into Germany, and the role of a primary animal distributor were elucidated. In addition, a seroprevalence study was performed among zoo animal caretakers from VSBV-1 affected zoos. No seropositive healthy zoo animal caretakers were found, underlining a probable high-case fatality rate of human VSBV-1 infections. This study illustrates the network and health consequences of uncontrolled wild pet trading as well as the benefits of molecular epidemiology for elucidation and future prevention of infection chains by zoonotic viruses. To respond to emerging zoonotic diseases rapidly, improved regulation and control strategies are urgently needed.

Standardized risk management in catheterization procedures for non-ST-segment elevation myocardial infarction: associations with in-hospital clinical outcomes

Introduction and purpose

Patient risk in non-ST-segment elevation myocardial infarction (NSTEMI) depends on clinical setting, individual patient variables and procedural characteristics. Standardized risk-adjusted periprocedural management for catheterization procedures using a Standard Operating Procedure (SOP) was investigated to evaluate associations with in-hospital clinical outcomes.

Methods

In 01/2018, our heart center established an SOP for coronary catheterization procedures in NSTEMI, targeting 1) standardized pre-procedural risk assessment using National Cardiovascular Data Registry (NCDR) risk models, and 2) standardized post-procedural risk-adjusted safety measures, including advanced patient monitoring (intermediate/intensive care) and use of vascular closure devices. All patients presenting with invasively-managed NSTEMI in 2018 were retrospectively evaluated for SOP-based pre-procedural risk scoring, SOP-based post-procedural management and in-hospital clinical outcomes of mortality, major bleeding (MB, according to BARC ≥3) and acute kidney injury (AKI, according to KDIGO).

Results

A total of 430 patients (age 72±12 years, 71% male, BMI 27±5) presenting with NSTEMI from 01 to 12/2018 were included, 9.8% presented in cardiogenic shock and 4.7% had suffered a preclinical cardiac arrest. Overall in-hospital mortality was 3.7%, MB occurred in 6.5%. 207 patients (48.1%, SOP+ group) had received both 1) pre-procedural risk assessment and 2) post-procedural risk-adjusted safety measures; the other 223 patients (51.9%, SOP- group) had not received either 1) or 2). There were no significant differences in baseline characteristics and prior-existing medical conditions between groups, however, significantly more patients in SOP- group were treated in emergency settings (39.9% vs. 21.7%, p=0.004). However, significantly more patients in SOP- were treated in emergency settings at higher risk (39.9% (SOP-) vs. 21.7% (SOP+); p<0.001). In univariate analysis, all in-hospital clinical outcomes of mortality (1.4% (SOP+) vs. 5.8% (SOP-); p=0.016), MB (2.9% (SOP+) vs. 9.9% (SOP-); p=0.003) and AKI were significantly lower in the SOP+ group (15.9% (SOP+) vs. 24.2% (SOP-); p=0.033). After correction for the difference in risk between groups due to emergency settings by multivariate logistic regression analysis, MB remained significantly lower in SOP+ (p=0.02), while mortality (p=0.14) and AKI (p=0.19) were not significantly associated with SOP-status anymore.

Conclusion

Standardized risk management in invasively managed NSTEMI was associated with significantly lower rates of in-hospital major bleedings.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Junior Clinician Scientist Track, Medical faculty, Heinrich-Heine-University Düsseldorf, Germany

Iron status, anemia and functional capacity in adults with congenital heart disease: a single center analysis

Background

Iron is essential to the mitochondrial energy production in cardiomyocytes and its depletion is negatively associated with symptoms, functional capacity, quality of life and outcomes in patients with heart failure – independent of anemia. The relevance of iron deficiency in adults with congenital heart disease however has not been evaluated to date, and we thus aimed to evaluate it in an all-comer cohort of patients with congenital heart disease in correlation with symptoms and functional capacity.

Methods and results

527 patient cases from one referral center over 2 years were evaluated concerning their iron status, anemia, functional capacity and ejection fraction of their systemic ventricle. 264 were female, 94 had a shunt lesion, 96 had left-sided obstructive lesions, 181 right-sided lesions, while 108 were considered to have complex lesions and 28 were cyanotic. The median age was 34 years, the mean BMI was 25.2±5 kg/m2, 429 patients had a normal ejection fraction and 34 moderately and severely depressed. 35 patients were classified as NYHA III, and 56 as NYHA II, while their functional capacity was evaluated via cardiopulmonary testing with a mean VO2max/kg of 22.6±6.5 and mean 69±17% of the expected. The mean serum iron concentration was 99.4±42.3 mcg/dL, their mean transferrin saturation was 27.36±13%, the mean ferritin concentration was 130.8±185 ng/mL, the mean soluble transfer factor was 1.3±0.66 mg/l and their mean Hemoglobin 14.8±2 mg/dL, while the mean MCV was 88±5.3 and the mean MCHC 33.7±1.4.

40 patients were anemic according to the WHO definition for anemia, in 28 of those patients that was already known. Iron deficiency according to stratified according to ferritin was present in 53 patients. However, when stratified according to the heart failure guidelines definition for iron deficiency 299 patients were found affected. Using the soluble transferrin receptor (sTfR) and sTfR-ferritin index iron deficiency was suspected in 10 additional individuals. Iron deficiency was associated with the ejection fraction (p=0.0001) - patients with moderately or severely depressed systemic ventricular function more often were diagnosed with iron deficiency (p=0.007)-, while it did not correlate with functional NYHA classification (p=0.622) or functional capacity (p=0.1 and 0.057). Iron deficiency was also not found significantly different amongst congenital defects but did correlate with all laboratory iron studies.

Conclusions

In this ambulatory population of adults with congenital heart disease we found an association of ejection fraction with iron deficiency, however no association of iron deficiency with functional capacity. The question arising is if a new definition of iron deficiency anemia in congenital heart disease similar to heart failure would be of clinical value.

Funding Acknowledgement

Type of funding source: None

Uninterrupted direct oral anticoagulants and vitamin K antagonists during ablation for atrial fibrillation: an updated meta-analysis

Background

Uninterrupted anticoagulation during catheter ablation of atrial fibrillation (CAAF) became standard of care after positive results of trials investigating vitamin K antagonists (VKA). Previous studies and meta-analyses of uninterrupted direct oral anticoagulants (DOAC) vs. VKA have given controversial results. We thus aimed to elucidate the risks and benefits of uninterrupted DOAC vs. VKA during CAAF in an updated meta-analysis of randomized controlled trials (RCTs).

Methods

Online databases were searched for RCTs comparing uninterrupted DOAC to VKA in patients undergoing CAAF until September 2019. Data from retrieved studies were analysed in a comprehensive meta-analysis. Primary safety outcome was major bleeding; primary efficacy outcome was stroke or transient ischemic attack (TIA). Secondary outcomes included a composite of major bleeding and stroke or TIA, minor bleeding, acute cerebral lesions on magnetic resonance imaging (ACL) and mortality.

Results

Six eligible RCTs comprising 2,369 patients were included. Pooled meta-analysis showed no significant differences in DOAC vs. VKA concerning the rates of major bleeding (2.2% vs. 3.8%; odds ratio (OR) 0.69, 95% confidence interval (CI) 0.30–1.56; p=0.37) and stroke or TIA (0.2% vs. 0.2%; OR 0.97, CI 0.20–4.72; p=0.97). There were no significant differences found in secondary outcomes (OR 0.73, p=0.49 for composite of major bleeding and stroke or TIA; OR 1.08, p=0.52 for minor bleeding; OR 1.12, p=0.59 for ACL; and OR=0.60, p=0.64 for all-cause mortality).

Conclusion

Our meta-analysis suggests that uninterrupted periprocedural anticoagulation with DOAC or VKA is characterized by a similar risk/benefit ratio in patients undergoing CAAF with comparable rates of major bleeding and stroke.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Medical faculty of the Heinrich-Heine-University Düsseldorf, Germany

Borna disease outbreak with high mortality in an alpaca herd in a previously unreported endemic area in Germany

Borna disease virus 1 (BoDV-1) is the causative agent of Borna disease, an often fatal neurologic condition of domestic mammals, including New World camelids, in endemic areas in Central Europe. Recently, BoDV-1 gained further attention by the confirmation of fatal zoonotic infections in humans. Although Borna disease and BoDV-1 have been described already over the past decades, comprehensive reports of Borna disease outbreaks in domestic animals employing state-of-the-art diagnostic methods are missing. Here, we report a series of BoDV-1 infections in a herd of 27 alpacas (Vicugna pacos) in the federal state of Brandenburg, Germany, which resulted in eleven fatalities (41%) within ten months. Clinical courses ranged from sudden death without previous clinical signs to acute or chronic neurologic disease with death occurring after up to six months. All animals that underwent necropsy exhibited a non-suppurative encephalitis. In addition, six apparently healthy seropositive individuals were identified within the herd, suggesting subclinical BoDV-1 infections. In infected animals, BoDV-1 RNA and antigen were mainly restricted to the central nervous system and the eye, and sporadically detectable in large peripheral nerves and neuronal structures in other tissues. Pest control measures on the farm resulted in the collection of a BoDV-1-positive bicoloured white-toothed shrew (Crocidura leucodon), while all other trapped small mammals were negative. A phylogeographic analysis of BoDV-1 sequences from the alpacas, the shrew and BoDV-1-positive equine cases from the same region in Brandenburg revealed a previously unreported endemic area of BoDV-1 cluster 4 in North-Western Brandenburg. In conclusion, alpacas appear to be highly susceptible to BoDV-1 infection and display a highly variable clinical picture ranging from peracute death to subclinical forms. In addition to horses and sheep, they can serve as sensitive sentinels used for the identification of endemic areas.

283Endovascular thrombectomy as a means to improve survival in acute ischemic stroke - A meta-analysis

Background and purpose

Although endovascular thrombectomy (EVT) in acute ischemic stroke (AIS) is guideline-recommended to improve functional recovery, thus far there are only inconclusive data from underpowered singular trials of EVT vs. medical therapy (MT) on mortality. We here aimed to perform a meta-analysis on short-term mortality in guideline-relevant EVT vs. MT randomized controlled trials (RCTs).

Methods

All randomized controlled trials (RCT) reporting EVT vs. MT in the latest 2018 American Stroke Association/American Heart Association (ASA/AHA) Guidelines were eligible for inclusion. Data were abstracted by two independent investigators and double-checked by four others. Study data were integrated using the Cochran-Mantel-Haenszel method and a random-effects model to compute summary statistics of risk ratios (RR) with 95% confidence intervals (CI). Ninety-day mortality and intracranial hemorrhage (ICH) were analyzed.

Results

Ten of the twelve guideline-relevant EVT vs. MT RCTs (DAWN, DEFUSE 3, ESCAPE, EXTEND-IA, MR CLEAN, MR RESCUE, REVASCAT, SWIFT PRIME, THERAPY, THRACE) with 2,313 patients were selected for inclusion. Studies IMS III and SYNTHESIS were excluded due to their very infrequent use of EVT. Stent retrievers (Trevo, Solitaire, Merci) were most frequently applied, followed by thrombus aspiration (Penumbra). Intravenous thrombolysis was administered in addition to EVT in the majority of patients. In the pooled meta-analysis of all eligible RCTs, EVT significantly reduced the risk for 90-day mortality by 3.7% compared to MT (15.0% vs. 18.7%; RR 0.81 with CI 0.68 to 0.98; p=0.03), accounting for a number-needed-to-treat of 27 to prevent one all-cause death. Trends were similar in early-window (RR 0.83) and late-window trials only (RR 0.76). There was no difference in the risk for ICH in EVT vs. MT (4.2% vs. 4.0%; RR 1.11 with CI 0.71 to 1.72; p=0.65). All included trials were published in high-quality journals and risk of bias was judged low.

Conclusions

This meta-analysis lends evidence to EVT benefits for survival already during the first 90 days after acute ischemic stroke. These results further highlight the evolution of interventional techniques in this setting.

P6268Cardiovascular outcomes of new anti-diabetic agents - A meta-analysis of randomized controlled trials

Background and purpose

The risk of major cardiovascular events (MACE) is increased in patients with diabetes mellitus. Recently published clinical trials of three different pharmacological classes (DPP4 inhibitors (DPP4i), SGLT2-inhibitors (SGLT2i), GLP-1-receptor-antagonists (GLP1RA)) of new anti-diabetic agents (ADA) showed potential benefits for cardiovascular (CV) outcomes. We thus aimed to perform a meta-analysis of randomized controlled trials (RCTs) of these ADA to elucidate benefits on CV outcomes in diabetic patients.

Methods

Following a systematic online database search, all RCTs reporting CV outcomes of DPP4i, SGLT2i or GLP1RA vs. Placebo in diabetic patients up until December 2018 were eligible for inclusion in the meta-analysis. Studies including patients with acute coronary syndrome (ACS) were excluded. Data were abstracted and analyzed with the inverse-variance method and a random-effects model, hazard ratios (HR) with 95% confidence intervals (CI) were used as summary statistics. CV outcomes of MACE, myocardial infarction (MI), stroke, heart failure (HF), CV death and all-cause mortality were analyzed.

Results

Eleven RCTs (DPP4i: SAVOR, TECOS, CARMELINA; GLP1RA: LEADER, SUSTAIN-6, EXSCEL, Harmony; SGLT2i: EMPA-REG OUTCOME, CANVAS Program, DECLARE) with 109,316 patients were selected for inclusion. ELIXA and EXAMINE were excluded due to their inclusion of patients with ACS, CAROLINA was excluded for lack of placebo-control. In the pooled meta-analysis of all trials, ADA significantly reduced the risk for MACE (Hazard ratio (HR) 0.91, CI 0.86–0.96, p=0.0004), MI (HR 0.91, CI 0.85–0.96, p=0.02), CV death (HR 0.9, CI 0.82–0.99, P=0.02) and all-cause mortality (HR 0.92, CI 0.85–0.99, p=0.03). There was no difference in the risk for stroke (HR 0.94, CI 0.87–1.02, p=0.16) and HF (HR 0.88, CI 0.76–1.02, p=0.08). In agent-specific subgroup analyses, GLP1RA and SGLT2i showed significant reductions in MACE (GLP1RA: HR 0.85, CI 0.78–0.92, p<0.0001; SGLT2i: HR 0.89, CI 0.83–0.96, p=0.001), MI (GLP1RA: HR 0.86, CI 0.76–0.98, p=0.02; SGLT2i: HR 0.88, CI 0.79–0.97, p=0.01) and all-cause mortality (GLP1RA: HR 0.88, CI 0.81–0.95; p=0.001; SGLT2i: HR 0.83, CI 0.70–0.99; p=0.03). GLP1RA significantly reduced risk for stroke (HR 0.85, CI 0.75–0.96, p=0.008) and CV death (HR 0.86, CI 0.78–0.95, p=0.002). SGLT2I were especially effective in the reduction of risk for HF (HR 0.69, CI 0.61–0.79; p<0.0001). DPP4i inhibitors however failed to show superiority in all analyzed outcomes.

Conclusions

This meta-analysis lends evidence to GLP1RA and SGLT2i benefits for MACE, MI and all-cause mortality, while DPP4i failed to show superiority in cardiovascular outcomes. Individualized medication for diabetic patients depending on CV disease status should be considered.

P2792Preoperative levosimendan improves survival in patients with low cardiac output syndrome undergoing cardiac surgery: a meta-analysis of randomized controlled trials

Background and purpose

Previous studies and meta-analyses of perioperative levosimendan to improve the outcomes of patients with low cardiac output syndrome (LCOS) undergoing cardiac surgery have given controversial results and the optimal time of infusion of levosimendan remains uncertain. We thus aimed to elucidate the risk/benefit ratio of preoperative levosimendan in a meta-analysis of randomized controlled trials (RCTs).

Methods

Online databases were searched for RCTs comparing preoperative levosimendan to placebo in patients with LCOS undergoing cardiac surgery until February 2019. Data from retrieved studies were abstracted and analyzed in a comprehensive meta-analysis. Primary outcome was all-cause mortality. Secondary outcomes included myocardial infarction, renal failure/replacement therapy, need for inotropic therapy, need for left ventricular assist devices, ventricular arrhythmia and arterial hypotension.

Results

As a result of the online database search, six eligible RCTs with 1,326 patients were included in the meta-analysis. Preoperative levosimendan showed a significant reduction in all-cause mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.29–0.83; p<0.01), renal failure/replacement therapy (OR 0.48, CI 0.29–0.80; p<0.01) and need for inotropic therapy (OR 0.24, CI 0.06–0.95; p=0.04) compared to placebo. There were no significant differences in levosimendan vs. placebo concerning the rates of myocardial infarction (OR 0.61, p=0.38), need for left ventricular assist devices (OR 0.38, p=0.1), ventricular arrhythmia (OR 0.7, p=0.33), and arterial hypotension (OR 1.28, p=0.07).

Conclusions

Preoperative administration of levosimendan may improve survival in patients with low cardiac output syndrome undergoing cardiac surgery. It reduces need for inotropic medical support and renal failure/replace-ment therapy compared to placebo.

P957Survival benefits of routine glycoprotein IIb/IIIa inhibitors during primary PCI in ST-segment elevation myocardial infarction: A meta-analysis of randomised controlled trials

Background

Cardiovascular guidelines recommend adjunct glycoprotein IIb/IIIa inhibitors (GPI) only in selected patients with acute ST-segment elevation myocardial infarction (STEMI).

Purpose

This study aimed to evaluate routine GPI use in STEMI treated with primary PCI.

Methods

Online databases were systematically searched for randomised controlled trials (RCTs) of routine GPI vs. control therapy in STEMI. Data from retrieved studies were abstracted and evaluated in a comprehensive meta-analysis using Mantel-Haenszel estimates of risk ratios (RR) as summary statistics.

Results

After systematic review, twenty-one RCTs with 8,585 patients were included: ten trials randomized tirofiban (T), nine abciximab (A), one eptifibatide (E), one trial used A+T; only one trial used DAPT with prasugrel/ ticagrelor. Routine GPI were associated with a significant reduction in all-cause mortality at 30 days (2.4% (GPI) vs. 3.2%; risk ratio (RR) 0.72; p=0.01) and 6 months (3.7% vs. 4.8%; RR 0.76; p=0.02), and a reduction in recurrent MI (1.1% vs. 2.1%; RR 0.55; p=0.0006), repeat revascularization (2.5% vs. 4.1%; RR 0.63; p=0.0001), TIMI flow <3 after PCI (5.4% vs. 8.2%; RR 0.61; p<0.0001) and ischemic stroke (RR 0.42; p=0.04). Major (4.7% vs. 3.4%; RR 1.35; p=0.005) and minor bleedings (7.2% vs. 5.1%; RR 1.39; p=0.006) but not intracranial bleedings (0.1% vs. 0%; RR 2.7; p=0.37) were significantly increased under routine GPI.

Conclusions

Routine GPI administration during primary PCI in STEMI resulted in mortality reduction, driven by reductions in recurrent ischemic events – however predominantly in trials pre-prasugrel/ticagrelor. Trials in contemporary STEMI management are needed to confirm these findings.

The opioid methadone induces a local anaesthetic-like inhibition of the cardiac Na⁺ channel, Na(v)1.5

BACKGROUND AND PURPOSE

Treatment with methadone is associated with severe cardiac arrhythmias, a side effect that seems to result from an inhibition of cardiac hERG K⁺ channels. However, several other opioids are inhibitors of voltage-gated Na⁺ channels. Considering the common assumption that an inhibition of the cardiac Na⁺ channel Na(v)1.5, is the primary mechanism for local anaesthetic (LA)-induced cardiotoxicity, we hypothesized that methadone has LA-like properties leading to a modulation of Na(v)1.5 channels.

EXPERIMENTAL APPROACH

The whole-cell patch clamp technique was applied to investigate the effects of methadone on wild-type and mutant human Na(v)1.5 channels expressed in HEK293 cells. A homology model of human Na(v)1.5 channels was used to perform automated ligand-docking studies.

KEY RESULTS

Methadone inhibited Na(v)1.5 channels in a state-dependent manner, that is, tonic block was stronger with inactivated channels than with resting channels and a use-dependent block at 10 Hz. Methadone induced a concentration-dependent shift of the voltage dependency of both fast and slow inactivation towards more hyperpolarized potentials, and impaired recovery from fast and slow inactivation. The LA-insensitive mutants N406K and F1760A exhibited reduced tonic and use-dependent block by methadone, and docking predictions positioned methadone in a cavity that was delimited by the residue F1760. Dextromethadone and levomethadone induced discrete stereo-selective effects on Na(v)1.5 channels.

CONCLUSIONS AND IMPLICATIONS

Methadone interacted with the LA-binding site to inhibit Na(v)1.5 channels. Our data suggest that these channels are a hitherto unrecognized molecular component contributing to cardiac arrhythmias induced by methadone.

Methadone is a local anaesthetic-like inhibitor of neuronal Na+ channels and blocks excitability of mouse peripheral nerves

BACKGROUND

Opioids enhance and prolong analgesia when applied as adjuvants to local anaesthetics (LAs). A possible molecular mechanism for this property is a direct inhibition of voltage-gated Na(+) channels which was reported for some opioids. Methadone is an effective adjuvant to LA and was recently reported to inhibit cardiac Na(+) channels. Here, we explore and compare LA properties of methadone and bupivacaine on neuronal Na(+) channels, excitability of peripheral nerves, and cell viability.

METHODS

Effects of methadone were explored on compound action potentials (CAP) of isolated mouse saphenous nerves. Patch clamp recordings were performed on Na(+) channels in ND7/23 cells, the α-subunits Nav1.2, Nav1.3, Nav1.7, and Nav1.8, and the hyperpolarization-activated cyclic nucleotide-gated channel 2 (HCN2). Cytotoxicity was determined using flow cytometry.

RESULTS

Methadone (IC50 86-119 µM) is a state-dependent and unselective blocker on Nav1.2, Nav1.3, Nav1.7, and Nav1.8 with a potency comparable with that of bupivacaine (IC50 177 µM). Both bupivacaine and methadone also inhibit C- and A-fibre CAPs in saphenous nerves in a concentration-dependent manner. Tonic block of Nav1.7 revealed a discrete stereo-selectivity with a higher potency for levomethadone than for dextromethadone. Methadone is also a weak blocker of HCN2 channels. Both methadone and bupivacaine induce a pronounced cytotoxicity at concentrations required for LA effects.

CONCLUSIONS

Methadone induces typical LA effects by inhibiting Na(+) channels with a potency similar to that of bupivacaine. This hitherto unknown property of methadone might contribute to its high efficacy when applied as an adjuvant to LA.

Stress Controlled Simultaneous On-line Measurements of Viscosity, Flow Exponent, and Melt Index

Capillary rheometers have been installed on-line very successfully for real time control of the quality of polymers in production and processing. A substantial extent of the real time information about the state of material and process is reached using an on-line rheometer with a wedge-shaped slit working under pressure controlled conditions. True viscosity, flow exponent and melt flow index can be measured simultaneously and changes in average molecular weight and molecular weight distributions are indicated immediately.

Genetische Analyse des individuellen Wachstums- und Futteraufnahmeverlaufs von Jungebern während der Eigenleistungsgruppenprüfung

Abstract. Title of the paper: Genetic analysis of the course of individual growth and feed intake of group-penned Performance tested boars Objective of the study was to analyse the course of feed intake and growth of 661 boars of three lines (259, 208, and 194 animals of lines 3, 4, and 8, respectively) during an age dependent Performance test between the 100th and 170th day of age. Individual feed intake of the group-penned animals was recorded by electronic feeding stations during the first, third, fifth, seventh, and ninth week on test. Additionally, each animal was weighted in biweekly intervalls. A second order polynomial and a third order polynomial were individually fitted on feed intake and live weight. From these curves, individual information about daily feed intake, daily gain, and food conversion ratio were derived for five periods of 12 days and for the entire period. Genetic parameters were estimated simultaneously using a multiple trait animal model. Heritabilities of h2 = .50, .55, .40, and .39 for traits of entire test period were found for backfat thickness, daily gain, daily feed intake, and food conversion ratio, respectively. Estimated heritabilities for each test period from one to five were h2 = .50, .56, .54, .50, and .37 for daily gain, h2 = .18, .43, .46, .45, and .38 for daily feed intake, and h2 = .34, .42, .46, .44, and .39 for food conversion. The genetic correlation between daily gain and food conversion in period one (rg = −.84) was significantly different from correlations between these traits in the following periods (rg = −.32 to −.51). Genetic correlations between daily gain and daily feed intake in each period were rg = .56 to .42 from first to last period. Except of first period (rg = −.11), the genetic associations between food conversion and daily feed intake for periods were similar (rg = .52 to .56). The genetic associations indicate, that a high feed intake in the beginning of the fattening period is desirable, while afterwards a more reduced feed intake should be achieved to improve efficiency of fattening Performance. In order to optimise fattening Performance, the use of part test information from growth rate and feed intake is necessary.

Genetische Beziehungen zwischen individueller Futteraufnahme während der Eigenleistungsprüfung und Fruchtbarkeitsmerkmalen beim Schwein

Abstract. Title of the paper. Genetic association between individual feed intake during Performance test and reproductions traits in pigs The present study deals with the estimation of genetic correlations between Performance test traits measured in boars and reproduction traits of their offspring (sibs) of two purebred lines. Performance traits were individual feed intake (FI) recorded by electronic feeder, feed conversion ratio (FCR), average daily gain (ADG) and backfat thickness (BF). Reproduction traits were number of total piglets born (NBT) and born alive (NBA) Data of 4869 young boars, Performance tested between April 1992 and May 1997 and data of 9710 primiparous sows farrowed between June 1994 to November 1998, were observed. Heritabilities of Performance traits recorded on Station were in line 03 (line 04) h2 = 0.24 (0.33), 0.33 (0.33), 0.23 (0.32) and 0.47 (0.53) for FI, ADG FCR and BF, respectively. Heritabilities of reproduction traits such as NBT, NBA were in line 03 (line 04) h2 = 0 05 (0.08) and 0.05 (0.06), respectively. Genetic correlation between individual feed intake and reproduction traits ranged between rg = 0.12 and 0.27. Undesirable genetic correlations were found between reproduction traits and feed efficiency (rg = 0.13 to 0.44), backfat thickness (rg = 0.07 to 0.25) and partly average daily gain (rg = −010 to 0.09). Line 04 showed lowest magnitude of feed intake and highest genetic antagonism between production and reproduction traits. It is suggested that feed intake capacity is a limiting factor for reproduction in line 04 and genetic antagonism between production and reproduction traits increases with reduction in feed intake.

Surgical treatment of piles: prospective, randomized study of Parks vs. Milligan-Morgan hemorrhoidectomy

PURPOSE

The present prospective, randomized clinical trial compares the outcome of surgical hemorrhoidectomy according to Parks and Milligan-Morgan in terms of hospital stay, duration of incapacity to work, symptom relief, length of morbidity, and patient convenience.

METHODS

Thirty-four consecutive patients with third or fourth degree internal hemorrhoids were randomly allocated to the two groups. Before surgery, all patients were interviewed using a standard questionnaire, followed by rectal examination. All patients underwent a follow-up interview and examinations 1, 2, 4, 8, and 12 weeks after the operation.

RESULTS

No serious postoperative complications were seen. Length of hospital stay (3.2 days for Parks hemorrhoidectomy vs. 4.6 days for Milligan-Morgan hemorrhoidectomy; 95 percent confidence interval, 0.2 and 2.6, respectively; P = 0.02) and mean duration of incapacity to work (12.3 days for Parks hemorrhoidectomy vs. 20.2 days for Milligan-Morgan hemorrhoidectomy; 95 percent confidence interval, 5.7 and 10.2, respectively; P < 0.001) differed significantly between the Milligan-Morgan and Parks patients. Until two weeks after the operation, Milligan-Morgan hemorrhoidectomy patients experienced significantly more pain.

CONCLUSIONS

Our study confirms that both operations are safe, easy to perform, and lead to satisfactory results. However, the Parks procedure is the preferred option, because it minimizes patients' postoperative discomfort, is more economic, has a significantly reduced hospital stay, and has a shorter time for return to work.