TASL Practice Guidance on the Clinical Assessment and Management of Patients with Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a multisystem disease and is significantly associated with obesity, insulin resistance, type 2 diabetes mellitus, metabolic syndrome, and cardiovascular disease. NAFLD has become the most prevalent chronic liver disease in Western countries, and the proportion of NAFLD-related cirrhosis among patients on liver transplantation waiting lists has increased. In light of the accumulated data about NAFLD, and to provide a common approach with multi-disciplines dealing with the subject, it has become necessary to create new guidance for diagnosing and treating NAFLD. This guidance was prepared following an interdisciplinary study under the leadership of the Turkish Association for the Study of the Liver (TASL), Fatty Liver Special Interest Group. This new TASL Guidance is a practical application guide on NAFLD and was prepared to standardize the clinical approach to diagnosing and treating NAFLD patients. This guidance reflects many advances in the field of NAFLD. The proposals in this guidance are meant to aid decision-making in clinical practice. The guidance is primarily intended for gastroenterology, endocrinology, metabolism diseases, cardiology, internal medicine, pediatric specialists, and family medicine specialists.

Association of the triglyceride glucose index as a measure of insulin resistance with mortality and cardiovascular disease in populations from five continents (PURE study): a prospective cohort study

BACKGROUND

The triglyceride glucose (TyG) index is an easily accessible surrogate marker of insulin resistance, an important pathway in the development of type 2 diabetes and cardiovascular diseases. However, the association of the TyG index with cardiovascular diseases and mortality has mainly been investigated in Asia, with few data available from other regions of the world. We assessed the association of insulin resistance (as determined by the TyG index) with mortality and cardiovascular diseases in individuals from five continents at different levels of economic development, living in urban or rural areas. We also examined whether the associations differed according to the country's economical development.

METHODS

We used the TyG index as a surrogate measure for insulin resistance. Fasting triglycerides and fasting plasma glucose were measured at the baseline visit in 141 243 individuals aged 35-70 years from 22 countries in the Prospective Urban Rural Epidemiology (PURE) study. The TyG index was calculated as Ln (fasting triglycerides [mg/dL] x fasting plasma glucose [mg/dL]/2). We calculated hazard ratios (HRs) using a multivariable Cox frailty model with random effects to test the associations between the TyG index and risk of cardiovascular diseases and mortality. The primary outcome of this analysis was the composite of mortality or major cardiovascular events (defined as death from cardiovascular causes, and non-fatal myocardial infarction, or stroke). Secondary outcomes were non-cardiovascular mortality, cardiovascular mortality, all myocardial infarctions, stroke, and incident diabetes. We also did subgroup analyses to examine the magnitude of associations between insulin resistance (ie, the TyG index) and outcome events according to the income level of the countries.

FINDINGS

During a median follow-up of 13·2 years (IQR 11·9-14·6), we recorded 6345 composite cardiovascular diseases events, 2030 cardiovascular deaths, 3038 cases of myocardial infarction, 3291 cases of stroke, and 5191 incident cases of type 2 diabetes. After adjusting for all other variables, the risk of developing cardiovascular diseases increased across tertiles of the baseline TyG index. Compared with the lowest tertile of the TyG index, the highest tertile (tertile 3) was associated with a greater incidence of the composite outcome (HR 1·21; 95% CI 1·13-1·30), myocardial infarction (1·24; 1·12-1·38), stroke (1·16; 1·05-1·28), and incident type 2 diabetes (1·99; 1·82-2·16). No significant association of the TyG index was seen with non-cardiovascular mortality. In low-income countries (LICs) and middle-income countries (MICs), the highest tertile of the TyG index was associated with increased hazards for the composite outcome (LICs: HR 1·31; 95% CI 1·12-1·54; MICs: 1·20; 1·11-1·31; p_interaction=0·01), cardiovascular mortality (LICs: 1·44; 1·15-1·80; p_interaction=0·01), myocardial infarction (LICs: 1·29; 1·06-1·56; MICs: 1·26; 1·10-1·45; p_interaction=0·08), stroke (LICs: 1·35; 1·02-1·78; MICs: 1·17; 1·05-1·30; p_interaction=0·19), and incident diabetes (LICs: 1·64; 1·38-1·94; MICs: 2·68; 2·40-2·99; p_interaction <0·0001). In contrast, in high-income countries, higher TyG index tertiles were only associated with an increased hazard of incident diabetes (2·95; 2·25-3·87; p_interaction <0·0001), but not of cardiovascular diseases or mortality.

INTERPRETATION

The TyG index is significantly associated with future cardiovascular mortality, myocardial infarction, stroke, and type 2 diabetes, suggesting that insulin resistance plays a promoting role in the pathogenesis of cardiovascular and metabolic diseases. Potentially, the association between the TyG index and the higher risk of cardiovascular diseases and type 2 diabetes in LICs and MICs might be explained by an increased vulnerability of these populations to the presence of insulin resistance.

FUNDING

Full funding sources are listed at the end of the paper (see Acknowledgments).

Comparison of frequency of silent cerebral infarction as assessed by serum neuron specific enolase in patients with non-valvular atrial fibrillation: Warfarin versus direct oral anticoagulant

BACKGROUND

Cerebral infarction in patients with atrial fibrillation (AF) may clinically vary from being silent to catastrophic. Silent cerebral infarction (SCI) is the neuronal injury in the absence of clinically appearent stroke or transient ischaemic attack. Serum neuron specific enolase (NSE) is suggested to be a valid surrogate biomarker that allows to detect recent neuronal injury. We aimed to evaluate the incidence of recent SCI by positive NSE levels in patients with non-valvular AF (NVAF) on oral anticoagulants.

METHODS

Blood samples for NSE were collected from 197 consecutive NVAF patients. NSE levels of greater than 12 ng/ml was considered as positive and suggestive of SCI.

RESULTS

Patients were mainly female with a mean age of 69 years. Ninety-eight of them (49.7%) were taking warfarin. Mean INR level was 2.3 ± 0.9. Mean CHA₂DS₂-VASc score of the study population was 3.5 ± 1.5. Seventy-two patients (36.5%) were found to have NSE elevation. They were more likely to have history of chronic heart failure and previous stroke/TIA. Increased left atrial diameter and higher CHA₂DS₂-VASc were other factors associated with SCI. Patients on DOACs and patients taking aspirin on top of oral anticoagulant treatment were less likely to have SCI. Multivariate analysis demonstrated that increased left atrial diameter (OR: 2.5; 95% CI: 1.52-4; p < 0.001) and use of warfarin (OR: 2.8; 95% CI: 1.37-5.61; p = 0.005) were detected as independent predictors of SCI.

CONCLUSIONS

Our study revealed that DOACs were associated with significantly reduced SCIs compared with warfarin, probably due to more effective and consistent therapeutic level of anticoagulation.

Availability and affordability of medicines and cardiovascular outcomes in 21 high-income, middle-income and low-income countries

Objectives

We aimed to examine the relationship between access to medicine for cardiovascular disease (CVD) and major adverse cardiovascular events (MACEs) among people at high risk of CVD in high-income countries (HICs), upper and lower middle-income countries (UMICs, LMICs) and low-income countries (LICs) participating in the Prospective Urban Rural Epidemiology (PURE) study.

Methods

We defined high CVD risk as the presence of any of the following: hypertension, coronary artery disease, stroke, smoker, diabetes or age >55 years. Availability and affordability of blood pressure lowering drugs, antiplatelets and statins were obtained from pharmacies. Participants were categorised: group 1—all three drug types were available and affordable, group 2—all three drugs were available but not affordable and group 3—all three drugs were not available. We used multivariable Cox proportional hazard models with nested clustering at country and community levels, adjusting for comorbidities, sociodemographic and economic factors.

Results

Of 163 466 participants, there were 93 200 with high CVD risk from 21 countries (mean age 54.7, 49% female). Of these, 44.9% were from group 1, 29.4% from group 2 and 25.7% from group 3. Compared with participants from group 1, the risk of MACEs was higher among participants in group 2 (HR 1.19, 95% CI 1.07 to 1.31), and among participants from group 3 (HR 1.25, 95% CI 1.08 to 1.50).

Conclusion

Lower availability and affordability of essential CVD medicines were associated with higher risk of MACEs and mortality. Improving access to CVD medicines should be a key part of the strategy to lower CVD globally.

Associations of Fish Consumption With Risk of Cardiovascular Disease and Mortality Among Individuals With or Without Vascular Disease From 58 Countries

IMPORTANCE

Cohort studies report inconsistent associations between fish consumption, a major source of long-chain ω-3 fatty acids, and risk of cardiovascular disease (CVD) and mortality. Whether the associations vary between those with and those without vascular disease is unknown.

OBJECTIVE

To examine whether the associations of fish consumption with risk of CVD or of mortality differ between individuals with and individuals without vascular disease.

DESIGN, SETTING, AND PARTICIPANTS

This pooled analysis of individual participant data involved 191 558 individuals from 4 cohort studies-147 645 individuals (139 827 without CVD and 7818 with CVD) from 21 countries in the Prospective Urban Rural Epidemiology (PURE) study and 43 413 patients with vascular disease in 3 prospective studies from 40 countries. Adjusted hazard ratios (HRs) were calculated by multilevel Cox regression separately within each study and then pooled using random-effects meta-analysis. This analysis was conducted from January to June 2020.

EXPOSURES

Fish consumption was recorded using validated food frequency questionnaires. In 1 of the cohorts with vascular disease, a separate qualitative food frequency questionnaire was used to assess intake of individual types of fish.

MAIN OUTCOMES AND MEASURES

Mortality and major CVD events (including myocardial infarction, stroke, congestive heart failure, or sudden death).

RESULTS

Overall, 191 558 participants with a mean (SD) age of 54.1 (8.0) years (91 666 [47.9%] male) were included in the present analysis. During 9.1 years of follow-up in PURE, compared with little or no fish intake (≤50 g/mo), an intake of 350 g/wk or more was not associated with risk of major CVD (HR, 0.95; 95% CI, 0.86-1.04) or total mortality (HR, 0.96; 0.88-1.05). By contrast, in the 3 cohorts of patients with vascular disease, the HR for risk of major CVD (HR, 0.84; 95% CI, 0.73-0.96) and total mortality (HR, 0.82; 95% CI, 0.74-0.91) was lowest with intakes of at least 175 g/wk (or approximately 2 servings/wk) compared with 50 g/mo or lower, with no further apparent decrease in HR with consumption of 350 g/wk or higher. Fish with higher amounts of ω-3 fatty acids were strongly associated with a lower risk of CVD (HR, 0.94; 95% CI, 0.92-0.97 per 5-g increment of intake), whereas other fish were neutral (collected in 1 cohort of patients with vascular disease). The association between fish intake and each outcome varied by CVD status, with a lower risk found among patients with vascular disease but not in general populations (for major CVD, I2 = 82.6 [P = .02]; for death, I2 = 90.8 [P = .001]).

CONCLUSIONS AND RELEVANCE

Findings of this pooled analysis of 4 cohort studies indicated that a minimal fish intake of 175 g (approximately 2 servings) weekly is associated with lower risk of major CVD and mortality among patients with prior CVD but not in general populations. The consumption of fish (especially oily fish) should be evaluated in randomized trials of clinical outcomes among people with vascular disease.

Drops That Change Their Mind: Spontaneous Reversal from Spreading to Retraction

A liquid drop may spread faster on surfaces when surfactants are added. Here we show that after some time the spreading in such systems can, under certain conditions, spontaneously reverse to retraction and the droplet pulls itself back, receding from areas it has just recently wetted, elevating its center of mass in a jerklike motion. The duration from drop placement to the onset of retraction ranges from hours to less than a second primarily as a function of surfactant concentration. When the retraction is asymmetric, it results in drop motion, and when it is symmetric, the mass of the drop collects itself on its spot. This phenomenon, which was predicted theoretically in 2014, is apparently a general one for drops with surfactants; however, other factors, such as evaporation and contamination, prevented its observance so far.

Relation of Acute Decompensated Heart Failure to Silent Cerebral Infarcts in Patients With Reduced Left Ventricular Ejection Fraction

Heart failure (HF) is a prothrombotic state with increased rate of thromboembolic events. Magnetic resonance imaging studies demonstrated increased rate of silent cerebral infarcts (SCI) in this patient group and SCIs were shown lead to dementia, cognitive decline, and depression. We aimed to show acute decompensated phase is associated with increased rate of recent SCI in reduced ejection fraction HF patients. HF patients with sinus rhythm hospitalized for acute decompensation were studied. Neuron specific enolase (NSE), a sensitive neuronal ischemia marker, was used to detect recent SCI. Decompensated and compensated phase blood samples for NSE were collected on the day of admission and on the third day of compensation, respectively. One hundred and forty seven patients with mean age of 72 were studied. There were significantly more patients with positive NSE levels at decompensated state (29% vs 4%, p <0.001). Multivariate predictors for recent SCI were smoking, new onset atrial fibrillation, spontaneous echo contrast of left ventricle, and aneurysmatic apex. Statin use was found to be protective against NSE elevation. In conclusion, our data reveal that decompensated HF is significantly associated with increased levels of NSE suggestive for silent neuronal injury.

Socioeconomic status and risk of cardiovascular disease in 20 low-income, middle-income, and high-income countries: the Prospective Urban Rural Epidemiologic (PURE) study

BACKGROUND

Socioeconomic status is associated with differences in risk factors for cardiovascular disease incidence and outcomes, including mortality. However, it is unclear whether the associations between cardiovascular disease and common measures of socioeconomic status-wealth and education-differ among high-income, middle-income, and low-income countries, and, if so, why these differences exist. We explored the association between education and household wealth and cardiovascular disease and mortality to assess which marker is the stronger predictor of outcomes, and examined whether any differences in cardiovascular disease by socioeconomic status parallel differences in risk factor levels or differences in management.

METHODS

In this large-scale prospective cohort study, we recruited adults aged between 35 years and 70 years from 367 urban and 302 rural communities in 20 countries. We collected data on families and households in two questionnaires, and data on cardiovascular risk factors in a third questionnaire, which was supplemented with physical examination. We assessed socioeconomic status using education and a household wealth index. Education was categorised as no or primary school education only, secondary school education, or higher education, defined as completion of trade school, college, or university. Household wealth, calculated at the household level and with household data, was defined by an index on the basis of ownership of assets and housing characteristics. Primary outcomes were major cardiovascular disease (a composite of cardiovascular deaths, strokes, myocardial infarction, and heart failure), cardiovascular mortality, and all-cause mortality. Information on specific events was obtained from participants or their family.

FINDINGS

Recruitment to the study began on Jan 12, 2001, with most participants enrolled between Jan 6, 2005, and Dec 4, 2014. 160 299 (87·9%) of 182 375 participants with baseline data had available follow-up event data and were eligible for inclusion. After exclusion of 6130 (3·8%) participants without complete baseline or follow-up data, 154 169 individuals remained for analysis, from five low-income, 11 middle-income, and four high-income countries. Participants were followed-up for a mean of 7·5 years. Major cardiovascular events were more common among those with low levels of education in all types of country studied, but much more so in low-income countries. After adjustment for wealth and other factors, the HR (low level of education vs high level of education) was 1·23 (95% CI 0·96-1·58) for high-income countries, 1·59 (1·42-1·78) in middle-income countries, and 2·23 (1·79-2·77) in low-income countries (p_interaction<0·0001). We observed similar results for all-cause mortality, with HRs of 1·50 (1·14-1·98) for high-income countries, 1·80 (1·58-2·06) in middle-income countries, and 2·76 (2·29-3·31) in low-income countries (p_interaction<0·0001). By contrast, we found no or weak associations between wealth and these two outcomes. Differences in outcomes between educational groups were not explained by differences in risk factors, which decreased as the level of education increased in high-income countries, but increased as the level of education increased in low-income countries (p_interaction<0·0001). Medical care (eg, management of hypertension, diabetes, and secondary prevention) seemed to play an important part in adverse cardiovascular disease outcomes because such care is likely to be poorer in people with the lowest levels of education compared to those with higher levels of education in low-income countries; however, we observed less marked differences in care based on level of education in middle-income countries and no or minor differences in high-income countries.

INTERPRETATION

Although people with a lower level of education in low-income and middle-income countries have higher incidence of and mortality from cardiovascular disease, they have better overall risk factor profiles. However, these individuals have markedly poorer health care. Policies to reduce health inequities globally must include strategies to overcome barriers to care, especially for those with lower levels of education.

FUNDING

Full funding sources are listed at the end of the paper (see Acknowledgments).

Urinary sodium excretion, blood pressure, cardiovascular disease, and mortality: a community-level prospective epidemiological cohort study

BACKGROUND

WHO recommends that populations consume less than 2 g/day sodium as a preventive measure against cardiovascular disease, but this target has not been achieved in any country. This recommendation is primarily based on individual-level data from short-term trials of blood pressure (BP) without data relating low sodium intake to reduced cardiovascular events from randomised trials or observational studies. We investigated the associations between community-level mean sodium and potassium intake, cardiovascular disease, and mortality.

METHODS

The Prospective Urban Rural Epidemiology study is ongoing in 21 countries. Here we report an analysis done in 18 countries with data on clinical outcomes. Eligible participants were adults aged 35-70 years without cardiovascular disease, sampled from the general population. We used morning fasting urine to estimate 24 h sodium and potassium excretion as a surrogate for intake. We assessed community-level associations between sodium and potassium intake and BP in 369 communities (all >50 participants) and cardiovascular disease and mortality in 255 communities (all >100 participants), and used individual-level data to adjust for known confounders.

FINDINGS

95 767 participants in 369 communities were assessed for BP and 82 544 in 255 communities for cardiovascular outcomes with follow-up for a median of 8·1 years. 82 (80%) of 103 communities in China had a mean sodium intake greater than 5 g/day, whereas in other countries 224 (84%) of 266 communities had a mean intake of 3-5 g/day. Overall, mean systolic BP increased by 2·86 mm Hg per 1 g increase in mean sodium intake, but positive associations were only seen among the communities in the highest tertile of sodium intake (p<0·0001 for heterogeneity). The association between mean sodium intake and major cardiovascular events showed significant deviations from linearity (p=0·043) due to a significant inverse association in the lowest tertile of sodium intake (lowest tertile <4·43 g/day, mean intake 4·04 g/day, range 3·42-4·43; change -1·00 events per 1000 years, 95% CI -2·00 to -0·01, p=0·0497), no association in the middle tertile (middle tertile 4·43-5·08 g/day, mean intake 4·70 g/day, 4·44-5.05; change 0·24 events per 1000 years, -2·12 to 2·61, p=0·8391), and a positive but non-significant association in the highest tertile (highest tertile >5·08 g/day, mean intake 5·75 g/day, >5·08-7·49; change 0·37 events per 1000 years, -0·03 to 0·78, p=0·0712). A strong association was seen with stroke in China (mean sodium intake 5·58 g/day, 0·42 events per 1000 years, 95% CI 0·16 to 0·67, p=0·0020) compared with in other countries (4·49 g/day, -0·26 events, -0·46 to -0·06, p=0·0124; p<0·0001 for heterogeneity). All major cardiovascular outcomes decreased with increasing potassium intake in all countries.

INTERPRETATION

Sodium intake was associated with cardiovascular disease and strokes only in communities where mean intake was greater than 5 g/day. A strategy of sodium reduction in these communities and countries but not in others might be appropriate.

FUNDING

Population Health Research Institute, Canadian Institutes of Health Research, Canadian Institutes of Health Canada Strategy for Patient-Oriented Research, Ontario Ministry of Health and Long-Term Care, Heart and Stroke Foundation of Ontario, and European Research Council.

Reply to Comment on "Solid-Liquid Work of Adhesion"

Extrand's interpretation in his "Comment on "Solid-Liquid Work of Adhesion" by Tadmor and Coworkers" may lead to an important discussion and physical understanding of the problem. Below, we compare the two approaches and elucidate the differences to put them in the right perspective.

Prognostic validation of a non-laboratory and a laboratory based cardiovascular disease risk score in multiple regions of the world

Objective

To evaluate the performance of the non-laboratory INTERHEART risk score (NL-IHRS) to predict incident cardiovascular disease (CVD) across seven major geographic regions of the world. The secondary objective was to evaluate the performance of the fasting cholesterol-based IHRS (FC-IHRS).

Methods

Using measures of discrimination and calibration, we tested the performance of the NL-IHRS (n=100 475) and FC-IHRS (n=107 863) for predicting incident CVD in a community-based, prospective study across seven geographic regions: South Asia, China, Southeast Asia, Middle East, Europe/North America, South America and Africa. CVD was defined as the composite of cardiovascular death, myocardial infarction, stroke, heart failure or coronary revascularisation.

Results

Mean age of the study population was 50.53 (SD 9.79) years and mean follow-up was 4.89 (SD 2.24) years. The NL-IHRS had moderate to good discrimination for incident CVD across geographic regions (concordance statistic (C-statistic) ranging from 0.64 to 0.74), although recalibration was necessary in all regions, which improved its performance in the overall cohort (increase in C-statistic from 0.69 to 0.72, p<0.001). Regional recalibration was also necessary for the FC-IHRS, which also improved its overall discrimination (increase in C-statistic from 0.71 to 0.74, p<0.001). In 85 078 participants with complete data for both scores, discrimination was only modestly better with the FC-IHRS compared with the NL-IHRS (0.74 vs 0.73, p<0.001).

Conclusions

External validations of the NL-IHRS and FC-IHRS suggest that regionally recalibrated versions of both can be useful for estimating CVD risk across a diverse range of community-based populations. CVD prediction using a non-laboratory score can provide similar accuracy to laboratory-based methods.

Usefulness of Neuron-Specific Enolase to Detect Silent Neuronal Ischemia After Percutaneous Coronary Intervention

Increased plasma levels of neuron-specific enolase (NSE) are related to damage of neurons and neuroendocrine cells. We aimed to investigate elevation of NSE after elective percutaneous coronary intervention (PCI) on the prediction of silent cerebral infarct (SCI). Study population consisted of 2 groups of patients. Group 1 included 92 consecutive patients with normal coronary angiograms, whereas group 2 consisted of 89 patients who underwent elective coronary stenting. NSE levels were studied before and 12 hours after the procedure. Elevation of >0.12 μg/L was considered as SCI. Forty-seven of 181 study patients (26%) had SCI after the procedure. NSE elevation was significantly more prevalent in patients with PCI than that of controls. Elevation of NSE was observed in 42% of patients who underwent elective PCI (n = 37) and 11% of the normal coronary artery group (n = 10) (p <0.001). The incidence of SCI was higher in active smokers and patients who had history of myocardial infarction (MI) (55% vs 10%, p <0.001 for active smokers and 40% vs 8%, p <0.001 for history of MI, respectively). Multivariate analysis demonstrated history of smoking (odds ratio [OR] 9.9; 95% confidence interval [CI] 3.7 to 26.9; p <0.001) and previous MI (OR 4.4; 95% CI 1.7 to 11.4; p = 0.01) as independent predictors of SCI. For patients who underwent elective PCI, NSE levels after procedure increases. Invasive coronary procedures have risk of SCIs, even in patients with normal coronary arteries. In conclusion, increased diagnosis of SCIs might improve understanding of their relation with invasive cardiac procedures, facilitate to prevent occurrence of silent microemboli and decrease the risk of adverse neurologic events.

Effect of a novel commercial potassium-oxalate containing tooth-desensitizing mouthrinse on the microhardness of resin composite restorative materials with different monomer compositions

Background

The effects of mouthrinses on dental resin composites have been investigated extensively. However, there is little information available regarding the effects of ‘newly developed mouthrinse’ formulations on the microhardness of different monomer based composite systems. Therefore, the aim of this study was to investigate the effect of a novel potassium-oxalate containing desensitizing mouthrinse on the microhardness of different monomer based composite materials.

Material and Methods

A hundred and twenty specimens (6mm in diameter and 2mm in height) were prepared for composite resin groups (methacrylate based, DX-511 monomer based and silorane monomer based) and for storage solution groups (artificial saliva and potassium oxalate-containing tooth-desensitizing mouthrinse). After allowing post-polimerization the baseline Knoop microhardness measurements for all specimens were recorded. The specimens were stored in 20 mL mouthwash and artificial saliva for 12 hours at 37ºC. The post-immersion microhardness values of all specimens were also recorded. Data were subjected to ANOVA/Scheffe’s test at a significance level of 0.05. The intra group (pre and post immersion values) comparison of the mean microhardness values of the specimens was done using Wilcoxon signed rank test.

Results

The microhardness of the silorane based composite was not affected significantly (p>0.05). The hardness values of the DX-511 monomer based composite and the methacrylate based composite exhibited a slight but not significant microhardness change compared to the baseline values (p>0.05).

Conclusions

Studies reported that the effect of mouthrinses on microhardness changes of composite resins may be material dependent, and the hardness change susceptibility of a restorative material may be attributed to its resin matrix or filler type. However, dental monomers as well as the oral care products have an ever-evolving technology and future studies should consider newer products. Potassium oxalate containing mouthrinses, especially alcohol-free ones, may be used safely with dental composites with newly developed low-shrink monomer compositions.

Key words:Microhardness, monomers, mouthrinses, potassium-oxalate.

Impact of metabolic syndrome on development of contrast-induced nephropathy after elective percutaneous coronary intervention among nondiabetic patients

BACKGROUND

Identifying patients who are vulnerable to development of contrast-induced nephropathy (CIN) is essential because of its association with prolonged hospitalization, increased cost, and increased in-hospital and long-term mortality rates.

HYPOTHESIS

Individual components of metabolic syndrome (MetS) are well-established risk factors for kidney injury. Nondiabetic patients diagnosed with MetS might be at an increased risk of developing CIN after elective percutaneous coronary intervention (PCI).

METHODS

A total of 599 nondiabetic patients were enrolled, of whom 313 met the MetS criteria and 286 were included in the control group. Patients were evaluated for development of CIN after elective PCI.

RESULTS

Contrast-induced nephropathy occurred in 9.3% (29 of 313) of the MetS group and 4.9% (14 of 286) of the control group (P = 0.04). The multivariable regression model revealed that baseline glomerular filtration rate < 30 mL/min, multivessel intervention, and MetS increased and use of statin decreased the probability of CIN independent from confounding factors (odds ratio [OR]: 7.84, 95% confidence interval [CI]: 3.46-24.36, P < 0.01 for baseline glomerular filtration rate < 30 mL/min; OR: 0.82, 95% CI: 0.42-0.96, P = 0.02 for statin use; OR: 2.64, 95% CI: 1.46-6.56, P < 0.01 for multivessel intervention; and OR: 1.66, 95% CI: 1.12-2.61, P = 0.03 for MetS).

CONCLUSIONS

Metabolic syndrome is a risk factor for CIN in patients with stable coronary artery disease who undergo elective PCI. We suggest that clinicians recognize the patients with MetS before elective coronary interventions.

Effect of angiotensin converting enzyme inhibitors on periprocedural myocardial infarction in patients with metabolic syndrome

BACKGROUND

Metabolic syndrome (MetS) has been reported as a risk factor for cardiovascular events. The aim of the present study is to investigate the association between chronic angiotensin-converting enzyme inhibitors (ACE-I) therapy and the rate of periprocedural myocardial infarction (PMI) after elective coronary stenting among patients with MetS.

METHODS

The inclusion criteria were MetS and plan for elective percutaneous coronary intervention. To assess the effect of ACE-I treatment on the incidence of PMI, measurements of cardiac biomarkers (CK-MB mass and troponin I) were performed at baseline and 24 h after the procedure.

RESULTS

A total of 459 patients fulfilling the inclusion criteria were recruited to chronic ACE-I treatment and ACE-I naive groups in a 2/1 ratio. Baseline troponin I and CK-MB levels were similar in both treatment groups, whereas they were significantly lower in ACE-I group 24 h after the procedure. Univariate analysis identified body mass index (BMI), LDL cholesterol, nitrate and ACE-I use as significant factors for the development of PMI. Multivariate regression model revealed that body mass index increased and use of nitrate and ACE-I decreased the probability of PMI independent from confounding factors (OR 1.14, 95% CI 1.05-1.23, p = 0.002 for BMI; OR 0.26, 95% CI 0.14-0.48, p = 0.01 for nitrate use, OR 0.51, 95% CI 0.27-0.93, p = 0.03 for ACE-I use).

CONCLUSIONS

This prospective observational cohort trial demonstrated that chronic ACE-I therapy was an independent predictor for reduced PMI among patients with MetS who underwent elective coronary intervention.

Urinary sodium and potassium excretion, mortality, and cardiovascular events

BACKGROUND

The optimal range of sodium intake for cardiovascular health is controversial.

METHODS

We obtained morning fasting urine samples from 101,945 persons in 17 countries and estimated 24-hour sodium and potassium excretion (used as a surrogate for intake). We examined the association between estimated urinary sodium and potassium excretion and the composite outcome of death and major cardiovascular events.

RESULTS

The mean estimated sodium and potassium excretion was 4.93 g per day and 2.12 g per day, respectively. With a mean follow-up of 3.7 years, the composite outcome occurred in 3317 participants (3.3%). As compared with an estimated sodium excretion of 4.00 to 5.99 g per day (reference range), a higher estimated sodium excretion (≥ 7.00 g per day) was associated with an increased risk of the composite outcome (odds ratio, 1.15; 95% confidence interval [CI], 1.02 to 1.30), as well as increased risks of death and major cardiovascular events considered separately. The association between a high estimated sodium excretion and the composite outcome was strongest among participants with hypertension (P=0.02 for interaction), with an increased risk at an estimated sodium excretion of 6.00 g or more per day. As compared with the reference range, an estimated sodium excretion that was below 3.00 g per day was also associated with an increased risk of the composite outcome (odds ratio, 1.27; 95% CI, 1.12 to 1.44). As compared with an estimated potassium excretion that was less than 1.50 g per day, higher potassium excretion was associated with a reduced risk of the composite outcome.

CONCLUSIONS

In this study in which sodium intake was estimated on the basis of measured urinary excretion, an estimated sodium intake between 3 g per day and 6 g per day was associated with a lower risk of death and cardiovascular events than was either a higher or lower estimated level of intake. As compared with an estimated potassium excretion that was less than 1.50 g per day, higher potassium excretion was associated with a lower risk of death and cardiovascular events. (Funded by the Population Health Research Institute and others.).

Steroid use in kidney transplant recipients presented with acute myocardial infarction

Suppression of the hypothalamic-pituitary-adrenal axis due to chronic exogenous steroid use is the most common cause of secondary adrenal insufficiency. Most kidney transplant recipients receive steroid therapy for immunosuppression; they are also at high risk for acute coronary events which can increase their physiological stress. Use of steroids early in the course of acute myocardial infarction (MI) raises concerns about the possibility of an increased risk of aneurysm formation and myocardial rupture. We present six case reports of kidney transplant recipients. Two of these recipients developed adrenal insufficiency after acute anterior MI; the life-threatening situation was successfully managed with corticosteroid administration. Four of these kidney transplant recipients presented with acute anterior MI; in these patients prophylactic steroid therapy prevented adrenal insufficiency, without any complication of the MI. We recommend the use of prophylactic corticosteroids for kidney transplant recipients to prevent adrenal insufficiency in the early course of acute MI.

Prevalence of a healthy lifestyle among individuals with cardiovascular disease in high-, middle- and low-income countries: The Prospective Urban Rural Epidemiology (PURE) study

IMPORTANCE

Little is known about adoption of healthy lifestyle behaviors among individuals with a coronary heart disease (CHD) or stroke event in communities across a range of countries worldwide.

OBJECTIVE

To examine the prevalence of avoidance or cessation of smoking, eating a healthy diet, and undertaking regular physical activities by individuals with a CHD or stroke event.

DESIGN, SETTING, AND PARTICIPANTS

Prospective Urban Rural Epidemiology (PURE) was a large, prospective cohort study that used an epidemiological survey of 153,996 adults, aged 35 to 70 years, from 628 urban and rural communities in 3 high-income countries (HIC), 7 upper-middle-income countries (UMIC), 3 lower-middle-income countries (LMIC), and 4 low-income countries (LIC), who were enrolled between January 2003 and December 2009.

MAIN OUTCOME MEASURES

Smoking status (current, former, never), level of exercise (low, <600 metabolic equivalent task [MET]-min/wk; moderate, 600-3000 MET-min/wk; high, >3000 MET-min/wk), and diet (classified by the Food Frequency Questionnaire and defined using the Alternative Healthy Eating Index).

RESULTS

Among 7519 individuals with self-reported CHD (past event: median, 5.0 [interquartile range {IQR}, 2.0-10.0] years ago) or stroke (past event: median, 4.0 [IQR, 2.0-8.0] years ago), 18.5% (95% CI, 17.6%-19.4%) continued to smoke; only 35.1% (95% CI, 29.6%-41.0%) undertook high levels of work- or leisure-related physical activity, and 39.0% (95% CI, 30.0%-48.7%) had healthy diets; 14.3% (95% CI, 11.7%-17.3%) did not undertake any of the 3 healthy lifestyle behaviors and 4.3% (95% CI, 3.1%-5.8%) had all 3. Overall, 52.5% (95% CI, 50.7%-54.3%) quit smoking (by income country classification: 74.9% [95% CI, 71.1%-78.6%] in HIC; 56.5% [95% CI, 53.4%-58.6%] in UMIC; 42.6% [95% CI, 39.6%-45.6%] in LMIC; and 38.1% [95% CI, 33.1%-43.2%] in LIC). Levels of physical activity increased with increasing country income but this trend was not statistically significant. The lowest prevalence of eating healthy diets was in LIC (25.8%; 95% CI, 13.0%-44.8%) compared with LMIC (43.2%; 95% CI, 30.0%-57.4%), UMIC (45.1%, 95% CI, 30.9%-60.1%), and HIC (43.4%, 95% CI, 21.0%-68.7%).

CONCLUSION AND RELEVANCE

Among a sample of patients with a CHD or stroke event from countries with varying income levels, the prevalence of healthy lifestyle behaviors was low, with even lower levels in poorer countries.

The relation between endothelial dependent flow mediated dilation of the brachial artery and coronary collateral development - a cross sectional study

BACKGROUND

Endothelial dysfunction is thought to be a potential mechanism for the decreased presence of coronary collaterals. The aim of the study was to investigate the association between systemic endothelial function and the extent of coronary collaterals.

METHODS

We investigated the association between endothelial function assessed via flow mediated dilation (FMD) of the brachial artery following reactive hyperemia and the extent of coronary collaterals graded from 0 to 3 according to Rentrop classification in a cohort of 171 consecutive patients who had high grade coronary stenosis or occlusion on their angiograms.

RESULTS

Mean age was 61 years and 75% were males. Of the 171 patients 88 (51%) had well developed collaterals (grades of 2 or 3) whereas 83 (49%) had impaired collateral development (grades of 0 or 1). Patients with poor collaterals were significantly more likely to have diabetes (p = 0.001), but less likely to have used statins (p = 0.083). FMD measurements were not significantly different among good and poor collateral groups (11.5 +/- 5.6 vs. 10.4 +/- 6.2% respectively, p = 0.214). Nitroglycerin mediated dilation was also similar (13.4 +/- 5.9 vs. 12.8 +/- 6.5%, p = 0.521).

CONCLUSION

No significant association was found between the extent of angiographically visible coronary collaterals and systemic endothelial function assessed by FMD of the brachial artery.

Electrocardiographic abnormalities in patients with organic erectile dysfunction: comparison with an age-matched control group

AIMS

Our purpose was to determine the incidence of electrocardiographic (ECG) abnormalities in patients with organic erectile dysfunction (ED) and to compare the results with an age-matched control (potent) group.

METHODS

A total of 218 men with ED of organic etiology formed our study group. A total of 210 age-matched men who had urologic disease other than ED served as control group. An experienced cardiologist who was blind to the primary diagnosis evaluated the ECGs in the entire group. The results were reported as either normal or abnormal according to the presence or absence of an abnormality suggestive for cardiovascular disease.

RESULTS

The mean age of the study and control groups was 58 years (range for the study group 28-82 years and for the control group 28-80 years). Abnormal ECG rates among patients with ED and control subjects were comparable. The incidences of ECG abnormalities in the study and control groups were 21.1% and 17.1%, respectively (P = 0,298). No ECG abnormality was detected in males younger than 40 in either group.

CONCLUSION

Middle-aged or older men with ED may carry potential risk for cardiovascular diseases in the absence of cardiovascular symptoms. However, patients with organic ED are not under increased risk for ECG abnormalities.

The effect of high-dose aspirin pre-treatment on the incidence of myonecrosis following elective coronary stenting

BACKGROUND

Inadequate platelet response to aspirin is associated with increased incidence of peri-procedural myonecrosis. Antiplatelet activity of aspirin can be improved by increasing the dose. High-dose aspirin pre-treatment, therefore, may reduce the incidence of myonecrosis post stenting.

METHODS AND RESULTS

Two-hundred patients taking 75-325 mg daily doses of aspirin for at least 2 weeks were randomized for addition or no addition of 500 mg aspirin before elective coronary stenting (aspirin 500 group, n=100 and control group, n=100). Primary endpoint was the occurrence of peri-procedural myonecrosis defined as creatine kinase-myocardial band (CK-MB) elevation of >1x upper limits of normal (ULN). Aspirin 500 patients were significantly younger and more likely to have family history of coronary artery disease, but less likely to have received statins than controls. Elevation of CK-MB was observed in 29% of aspirin 500 patients and 15% of controls (p=0.017). The incidence of non-Q wave myocardial infarction (CK-MB elevation of >3xULN) tended to be higher in the aspirin 500 group than in the control group (5% versus 0%, p=0.059). Multivariate analysis identified baseline aspirin dose (OR: 1.006; 95% CI: 1.002-1.010; p=0.004), aspirin 500 mg treatment (OR: 2.5; 95% CI: 1.2-5.5; p=0.021) and baseline CK-MB level (OR: 1.4; 95% CI: 1.1-1.7; p=0.012) as independent predictors of CK-MB elevation after coronary stenting.

CONCLUSION

For patients taking daily low-dose aspirin therapy, supplementation with high-dose aspirin before elective coronary stenting does not reduce, but may increase the incidence of peri-procedural myonecrosis.

Relationship between angiotensin-converting enzyme gene polymorphism and severity of aortic valve calcification

OBJECTIVE

To investigate the role of angiotensin-converting enzyme (ACE) gene polymorphism in patients with degenerative aortic valve calcification (AVC).

PATIENTS AND METHODS

Our study consisted of 305 Turkish patients of European descent (139 male, 166 female; mean plus or minus age, 68 plus or minus 9 years) referred to our echocardiography laboratory for aortic valve evaluation between June 2, 2003, and April 29, 2005. The severity of AVC was graded from 1 to 6 by echocardiography. We used polymerase chain reaction to determine ACE gene polymorphism.

RESULTS

The ACE insertion/deletion genotype distributions for the study population were in Hardy-Weinberg equilibrium (chi square equals 3.5, P equals .18). The study population was divided into 3 groups based on the severity of AVC: those with grade 1 calcification were in group 1, those with grades 2 to 4 in group 2, and those with grades 5 to 6 in group 3. Group 1 patients were significantly younger, less likely to have hypertension and diabetes, and had higher high-density lipoprotein cholesterol levels. The genotype frequencies were significantly different among groups, with the insertion/insertion genotype being less prevalent in group 3 patients. In multivariate analysis, independent predictors of severe AVC were hypertension (odds ratio [OR], 5.6; 95% confidence interval [CI], 2.8 to 11.0; P less than .001), low high-density lipoprotein cholesterol (OR, 2.7; 95 percent CI, 1.5 to 4.9; P equals .001), and the deletion/deletion and insertion/deletion vs insertion/insertion genotype (OR, 3.2; 95 percent CI, 1.5 to 7.2; P equals .004).

CONCLUSION

These results suggest that ACE gene polymorphism may be associated with severe AVC.

Epidural magnesium reduces postoperative analgesic requirement

BACKGROUND

Magnesium has antinociceptive effects in animal and human models of pain. Our hypothesis was that the addition of magnesium to postoperative epidural infusion of fentanyl may decrease the need for fentanyl.

METHODS

Fifty patients undergoing hip surgery were enrolled to receive either fentanyl (Group F) or fentanyl plus magnesium sulphate (Group FM) for 24 h for epidural analgesia. All patients were equipped with a patient-controlled epidural analgesia device and the initial settings of a demand bolus dose of fentanyl 25 microg. In Group FM, patients received 50 mg magnesium sulphate epidurally as an initial bolus dose followed by a continuous infusion of 100 mg day(-1). Ventilatory frequency, heart rate, blood pressure, pain assessment using a visual analogue scale (VAS), sedation scores and fentanyl consumption were recorded in the postoperative period.

RESULTS

There was no significant difference between groups in the time to first analgesic requirement. Compared with Group F, patients in Group FM received smaller doses of epidural fentanyl (P < 0.05). The cumulative fentanyl consumption in 24 h was 437 (SD110) microg in Group F and 328 (121) microg in Group FM (P < 0.05). Patients in Group F showed a higher VAS score in the first hour of the postoperative period (P < 0.05). The groups were similar with respect to haemodynamic and respiratory variables, sedation, pruritus, and nausea.

CONCLUSION

Co-administration of magnesium for postoperative epidural analgesia results in a reduction in fentanyl consumption without any side-effects.

The Relationship of Chronic Angiotensin Converting Enzyme Inhibitor Use and Coronary Collateral Vessel Development

BACKGROUND

Angiotensin II induces various growth factors such as vascular endothelial growth factor, platelet-derived growth factor, and fibroblast growth factor, and recent studies suggest that the expression of these growth factors promotes collateral growth. We hypothesized that the blockage of angiotensin II production by ACE inhibitors might interfere with collateral development in patients with coronary occlusion.

METHODS

The study group consisted of 187 patients (114 males, mean ages, 62 +/- 11 years) who had chronic (> 1 month) coronary occlusion (TIMI flow grade < or = 1) in one of 3 epicardial coronary arteries. Collaterals were graded using the Rentrop classification, and the patients were divided into 2 groups according to having good (grade 2 and 3) or poor (grade 0 and 1) collaterals (n = 127 and 60, respectively). Clinical and angiographic characteristics were compared in the 2 groups.

RESULTS

ACE inhibitor use (52% versus 35%, P = 0.04) and the prevalence of diabetes mellitus (DM) (43% versus 27%, P = 0.02) was higher in patients with poor collaterals. Patients with poor collaterals had a higher frequency of circumflex artery (Cx) occlusion, worse wall motion, and lower ejection fraction. In multivariate analysis, ACE inhibitor use (OR: 2.4; 95% CI = 1.23-4.68, P = 0.01) and the occlusion of Cx (OR: 3.3, 95% CI; 1.33-8.12, P = 0.01) were found to be independent predictors for poor collateral development, whereas there was a trend for DM as a predictor for poor collaterals (OR: 1.9, 95% CI = 0.97-3.8, P = 0.06).

CONCLUSION

The findings suggest that ACE inhibitor therapy may contribute to poor collateral development in patients with coronary occlusion.

Naproxen treatment prevents periprocedural inflammatory response but not myocardial injury after percutaneous coronary intervention

BACKGROUND AND AIM

Recent studies have documented that elevation of C-reactive protein (CRP) levels after percutaneous coronary intervention (PCI) have been predictive of adverse outcome. This study was performed to test the hypothesis that preprocedural use of naproxen sodium is associated with a reduction in the extent of inflammatory response and myocardial injury after PCI.

METHODS

Ninety-seven patients who were scheduled for elective PCI were randomized either for naproxen sodium (500 mg bid) (n:39, 75% male, 59+/-10 years) or control (n:58, 76% male, 60+/-10 years). All patients were troponin negative before the procedure. Blood samples for CRP, Troponin I and CK-MB were collected at baseline and after the procedure.

RESULTS

The characteristics were similar between the two groups. After coronary stenting, the rise in CRP levels was significantly higher in controls than those treated with naproxen (DeltaCRP=6.4 mg/L in the controls and 0.43 mg/L in the naproxen group, p<0.0001). The incidence of any troponin I elevation or CK-MB elevation above upper limit of normal was not statistically different between groups. During follow up (12+/-2 months), major cardiac adverse events (death, myocardial infarction, and revascularization of target lesion) was similar between groups.

CONCLUSION

Our data show that naproxen pretreatment leads to significant suppression in PCI related CRP elevation. However this improvement in CRP levels was not associated with any significant reduction in post-PCI myonecrosis.

Unrecognized side effect of statin treatment: unilateral blepharoptosis

A 43-year-old man receiving statin monotherapy (10 mg atorvastatin) for hypercholesterolemia had unilateral blepharoptosis as the result of isolated myositis of the levator muscle. Statin-induced myositis in the levator muscle should be considered in the differential diagnosis of acquired unilateral blepharoptosis of unknown cause.

Elevated levels of C-reactive protein are associated with impaired coronary collateral development

BACKGROUND

In vitro studies have shown that C-reactive protein (CRP) attenuates nitric oxide production and inhibits angiogenesis, which may result in impaired collateral development. The aim of this study was to investigate the association between high sensitivity CRP (hsCRP) levels and the extent of coronary collaterals.

MATERIALS AND METHODS

We investigated the association between hsCRP levels and the extent of coronary collaterals according to the Rentrop classification in a cohort of 185 patients who had high-grade coronary stenosis or occlusion on their angiograms.

RESULTS

Mean age was 62 years and 80% were males. Subjects with a higher grade of collaterals were significantly less likely to have diabetes mellitus (OR; 0.48, 95% and CI; 0.28, 0.83) or acute coronary syndrome (OR; 0.58, 95% and CI; 0.33, 0.99), but they were more likely to have higher number of vessels with significant stenosis (OR; 1.41, 95% and CI; 1.03, 1.93) and to have received statins (OR; 1.84, 1.09, 3.13). The mean hsCRP values reduced significantly as the Rentrop grades increased (trend, P = 0.0006). After adjusting for age, gender, statin use, clinical presentation with acute coronary syndrome, diabetes mellitus and the number of vessels with significant stenosis, each 10-unit increase in hsCRP values corresponded to a 31% reduced odds of having a higher collateral score (OR; 0.69, 95% and CI; 0.53, 0.90).

CONCLUSIONS

Our findings indicate that elevated hsCRP levels are associated with a significant impairment in coronary collateralization. These data suggest a previously unrecognized mechanism through which inflammation may worsen cardiovascular outcomes.

Myonecrosis after elective percutaneous coronary intervention: effect of clopidogrel-statin interaction

BACKGROUND

A recent ex vivo study suggests that the metabolic activation of clopidogrel is catalyzed by cytochrom P450 (CYP) 3A4 and is competitively inhibited by atorvastatin, but not pravastatin.

OBJECTIVE

To determine whether the incidence of procedure-related myocardial injury, assessed by cardiac troponin T (cTnT) release, is altered when clopidogrel is coadministered with a statin that is predominantly CYP3A4-metabolized.

METHODS AND RESULTS

Of the 211 consecutive patients who underwent coronary stenting after pretreatment with clopidogrel, 114 were receiving a CYP3A4-metabolized statin (59 simvastatin and 55 atorvastatin, Group 1), and 37 were receiving a non-CYP3A4-metabolized statin (30 pravastatin and 7 fluvastatin, Group 2) whereas 60 patients were not taking any statins (Control). All were troponin-negative before the procedure. The overall incidence of postprocedural cTnT positivity (> 0.10 ng/ml) was 30.8%. Group 2 patients were less likely to exhibit cTnT rise relative to Group 1 patients (8% versus 41.6%; p = 0.004) and relative to controls (8% versus 32.5%; p < 0.001). Multivariate analysis identified the use of a non-CYP3A4-metabolized statin before coronary stenting as the sole independent predictor for lower incidence of procedure-related cTnT elevation with estimated Odds ratios of 0.16 relative to no statin therapy (95% CI: 0.04-0.59; p = 0.006) and 0.18 relative to CYP3A4-metabolized statin therapy (95 CI: 0.053-0.637; p = 0.008)

CONCLUSION

Benefit derived from the preprocedural use of pravastatin and fluvastatin but not atorvastatin and simvastatin suggest that the ex vivo finding of a negative interaction when coadministering a CYP3A4-metabolized statin with clopidogrel may be of clinical significance.

Angiographic evaluation of myocardial perfusion in patients with syndrome X

We evaluated tissue level perfusion in patients who had syndrome X using the myocardial blush grade technique. Normal tissue perfusion in all coronary territories was observed in 23 patients (41.8%) who had syndrome X and in 44 control subjects (80%). Total myocardial blush score (sum of the myocardial blush grades of each coronary territory) was significantly lower in patients who had syndrome X than in control subjects (8.2 +/- 0.7 vs 8.7 +/- 0.5, p <0.0001). We have demonstrated for the first time that a substantial number of patients who have syndrome X have impaired tissue level perfusion, and this might be assumed as a surrogate marker of a diseased microvascular network in the catheterization laboratory.

Effects of clonidine pre-treatment on bupivacaine and ropivacaine cardiotoxicity in rats

BACKGROUND AND OBJECTIVE

Clonidine has cardiac and systemic effects that can modify the potentially lethal cardiovascular effects of local anaesthetics. We evaluated the effects of clonidine pre-treatment on cardiotoxicity induced by an infusion of bupivacaine or ropivacaine and the success rate of resuscitation in anaesthetized rats.

METHODS

Thirty-two Sprague-Dawley rats (250-300 g) were anaesthetized with thiopental and ketamine. Lung ventilation was maintained mechanically, and the electrocardiograph and invasive blood pressure were recorded continuously. Two separate groups of rats were treated with intravenous clonidine 5 microg kg(-1) (n = 16) or saline (n = 16) in a randomized fashion. Fifteen minutes later, each group was randomly subdivided into two equal groups and an infusion of bupivacaine or ropivacaine, 3 mg kg(-1) min(-1), was given until cardiac arrest (asystole) occurred. The times when the cardiotoxic events (25%, 50% and 75% reduction of arterial pressure and heart rate, first dysrhythmia and asystole, respectively), induced by the local anaesthetic, occurred and the resuscitation outcome scores were recorded.

RESULTS

Clonidine reduced heart rate and arterial pressure (P < 0.01). Clonidine did not alter cardiotoxicity or the success rate of resuscitation in bupivacaine-treated rats. In the ropivacaine group, clonidine increased the 25%, 50% and 75% reduction times of arterial pressure and the 50% and 75% reduction times of heart rate, times to first dysrhythmia and asystole (P < 0.05). Clonidine also increased the success rate of resuscitation in ropivacaine-treated rats (P < 0.05).

CONCLUSIONS

Although pre-treatment with clonidine protects the effects of ropivacaine cardiotoxicity and increases the success rate of resuscitation, it does not affect bupivacaine toxicity.

Phase I/II radioimmunotherapy trial with iodine-131-labeled monoclonal antibody G250 in metastatic renal cell carcinoma

This Phase I/II radioimmunotherapy study was carried out to determine the maximum tolerated dose (MTD) and therapeutic potential of 131I-G250. Thirty-three patients with measurable metastatic renal cell carcinoma were treated. Groups of at least three patients received escalating amounts of 1311I (30, 45, 60, 75, and 90 mCi/m2) labeled to 10 mg of mouse monoclonal antibody G250, administered as a single i.v. infusion. Fifteen patients were studied at the MTD of activity. No patient had received prior significant radiotherapy; one had received prior G250. Whole-body scintigrams and single-photon emission computed tomography images were obtained in all patients. There was targeting of radioactivity to all known tumor sites that were > or =2 cm. Reversible liver function test abnormalities were observed in the majority of patients (27 of 33 patients). There was no correlation between the amount of 131I administered or hepatic absorbed radiation dose (median, 0.073 Gy/mCi) and the extent or nature of hepatic toxicity. Two of the first six patients at 90 mCi/m2 had grade > or =3 thrombocytopenia; the MTD was determined to be 90 mCi/m2 131I. Hematological toxicity was correlated with whole-body absorbed radiation dose. All patients developed human antimouse antibodies within 4 weeks posttherapy; retreatment was, therefore, not possible. Seventeen of 33 evaluable patients had stable disease. There were no major responses. On the basis of external imaging, 131I-labeled mouse monoclonal antibody G250 showed excellent localization to all tumors that were > or =2 cm. Seventeen of 33 patients had stable disease, with tumor shrinkage observed in two patients. Antibody immunogenicity restricted therapy to a single infusion. Studies with a nonimmunogenic G250 antibody are warranted.