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31.
Tobacco smoking is a risk factor for atrial fibrillation (AF), but little is known about the impact of smoking in patients with AF. Of the 4060 patients with recurrent AF in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) trial, 496 (12%) reported having smoked during the past two years. Propensity scores for smoking were estimated for each of the 4060 patients using a multivariable logistic regression model and were used to assemble a matched cohort of 487 pairs of smokers and nonsmokers, who were balanced on 46 baseline characteristics. Cox and logistic regression models were used to estimate the associations of smoking with all-cause mortality and all-cause hospitalization, respectively, during over 5 years of follow-up. Matched participants had a mean age of 70 ± 9 years (± S.D.), 39% were women, and 11% were non-white. All-cause mortality occurred in 21% and 16% of matched smokers and nonsmokers, respectively (when smokers were compared with nonsmokers, hazard ratio=HR=1.35; 95% confidence interval=95%CI=1.01-1.81; p=0.046). Unadjusted, multivariable-adjusted and propensity-adjusted HR (95% CI) for all-cause mortality associated with smoking in the pre-match cohort were: 1.40 (1.13-1.72; p=0.002), 1.45 (1.16-1.81; p=0.001), and 1.39 (1.12-1.74; p=0.003), respectively. Smoking had no association with all-cause hospitalization (when smokers were compared with nonsmokers, odds ratio=OR=1.21; 95%CI=0.94-1.57, p=0.146). Among patients with AF, a recent history of smoking was associated with an increased risk of all-cause mortality, but had no association with all-cause hospitalization.  相似文献   
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Maintenance of normal potassium (K(+)) homeostasis has become an increasingly important limiting factor in the therapy of heart failure (HF). With the application of loop diuretics and digoxin, hypokalemia has become a frequent and feared side effect of treatment. Low serum K(+) in HF may be also a marker of increased neurohormonal activity and disease progression. To gain the maximum benefit from treatment, we need to individualize drug use and carefully monitor electrolytes. Symptomatic HF patients (New York Heart Association class III-IV) should be prescribed the lowest dose of diuretic necessary to maintain euvolemia. Mild hypokalemia may be corrected by the use of aldosterone receptor antagonists such as spironolactone or eplerenone. However, a more severe hypokalemia should preferably be corrected using K(+) supplement. Serum K levels should be frequently checked and maintained between 4.0 and 5.5 mEq/l (mmol/l).  相似文献   
34.
Cardiovascular drugs are used in pregnancy to treat maternal and fetal conditions. Mothers may also require drug therapy postpartum. Most cardiovascular drugs taken by pregnant women can cross the placenta and therefore expose the developing embryo and fetus to their pharmacologic and teratogenic effects. These effects are influenced by the intrinsic pharmacokinetic properties of a given drug and by the complex physiologic changes occurring during pregnancy. Many drugs are also transferred into human milk with potential adverse effects on the nursing infant. This article summarizes some of the literature concerning the risks and benefits of using cardiovascular drugs during pregnancy.  相似文献   
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Heart failure (HF) and obesity are major public health problems. Studies have shown that obesity may increase the risk of developing new HF but after patients have developed HF, obesity may be associated with improved outcomes. This paradoxical association of obesity with HF remains poorly understood. It is believed that the obesity paradox may in part be due to the inherent limitations of body mass index (BMI) as a measure of obesity. BMI may not appropriately measure important components of body mass like body fat, fat distribution, lean body mass, and body fluid content and may not be ideal for examining the relationship of body composition with health outcomes. Differentiating between body fat and lean body mass may explain some of the paradoxical association between higher BMI and better prognosis in patients with HF. Paradoxical outcomes in HF may also be due to phenotypes of obesity. Future studies need to develop and test metrics that may better measure body composition and may serve as a better tool for the estimation of the true association of obesity and outcomes in HF and determine whether the association may vary by obesity phenotypes.
  • KEY MESSAGES
  • Obesity predisposes to heart failure in all age groups. But obesity in heart failure is an area of controversy, because of obesity paradox, the apparent protective effect of overweight and mild obesity on mortality after development of heart failure.

  • Traditional markers of obesity do not measure different components of body weight like muscle mass, fat, water, and skeletal weight. Body Mass Index in heart failure subjects does not measure accurately body fat or fluid retention. So new markers of obesity like visceral adiposity index, body composition analysis, sarcopenic status assessment may be helpful in the assessment of heart failure outcomes.

  • Different phenotypes of obesity may be responsible for the different morbidity, mortality as well as therapeutic outcomes in heart failure.

  相似文献   
37.
The year 2013 proved to be very exciting as far as landmark trials and new guidelines in the field of lipid disorders, blood pressure and kidney diseases. Among these are the International Atherosclerosis Society Global Recommendations for the Management of Dyslipidemia, European Society of Cardiology (ESC)/European Society of Hypertension Guidelines for the Management of Arterial Hypertension, American Diabetes Association Clinical Practice Recommendations, the Kidney Disease: Improving Global Outcomes Clinical Practice Guidelines for Managing Dyslipidemias in Chronic Kidney Disease (CKD) Patients, the American College of Cardiology/American Heart Association Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults, the Joint National Committee Expert Panel (JNC 8) Evidence-Based Guideline for the Management of High Blood Pressure in Adults, the American Society of Hypertension/International Society of Hypertension Clinical Practice Guidelines for the Management of Hypertension in the Community, the American College of Physicians Clinical Practice Guideline on Screening, Monitoring, and Treatment of Stage 1–3 CKD and many important trials presented among others during the ESC Annual Congress in Amsterdam and the American Society of Nephrology Annual Meeting—Kidney Week in Atlanta, GA. The paper is an attempt to summarize the most important events and reports in the mentioned areas in the passing year.  相似文献   
38.
Background contextGadolinium-enhanced magnetic resonance imaging (Gd-MRI) is often performed in the evaluation of patients with persistent sciatica after lumbar disc surgery. However, correlation between enhancement and clinical findings is debated, and limited data are available regarding the reliability of enhancement findings.PurposeTo evaluate the reliability of Gd-MRI findings and their correlation with clinical findings in patients with sciatica.Study designProspective observational evaluation of patients who were enrolled in a randomized trial with 1-year follow-up.Patients samplePatients with 6- to 12-week sciatica, who participated in a multicentre randomized clinical trial comparing an early surgery strategy with prolonged conservative care with surgery if needed. In total 204 patients underwent Gd-MRI at baseline and after 1 year.Outcome measuresPatients were assessed by means of the Roland Disability Questionnaire (RDQ) for sciatica, visual analog scale (VAS) for leg pain, and patient-reported perceived recovery at 1 year. Kappa coefficients were used to assess interobserver reliability.MethodsIn total, 204 patients underwent Gd-MRI at baseline and after 1 year. Magnetic resonance imaging findings were correlated to the outcome measures using the Mann-Whitney U test for continuous data and Fisher exact tests for categorical data.ResultsPoor-to-moderate agreement was observed regarding Gd enhancement of the herniated disc and compressed nerve root (kappa<0.41), which was in contrast with excellent interobserver agreement of the disc level of the herniated disc and compressed nerve root (kappa>0.95). Of the 59 patients with an enhancing herniated disc at 1 year, 86% reported recovery compared with 100% of the 12 patients with nonenhancing herniated discs (p=.34). Of the 12 patients with enhancement of the most affected nerve root at 1 year, 83% reported recovery compared with 85% of the 192 patients with no enhancement (p=.69). Patients with and without enhancing herniated discs or nerve roots at 1 year reported comparable outcomes on RDQ and VAS-leg pain.ConclusionsReliability of Gd-MRI findings was poor-to-moderate and no correlation was observed between enhancement and clinical findings at 1-year follow-up.  相似文献   
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BACKGROUND: There is a marked underutilization of antiplatelet drugs, beta blockers, angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), and lipid-lowering drugs, and an overutilization of calcium channel blockers in elderly patients with coronary artery disease (CAD). METHODS: An ongoing educational program is being given by Dr. Wilbert Aronow on the appropriate utilization of cardiovascular drugs in patients with CAD during hospitalization and at hospital discharge. In a prospective study, charts of 200 unselected patients hospitalized for CAD at least 6 months after the onset of the educational program were analyzed by a medical resident to investigate the appropriate utilization of cardiovascular drugs. The 200 patients included 115 men and 85 women, mean age 70 years, with documented CAD. Of the 200 patients, 127 (64%) had the diagnosis of prior CAD. The use of cardiovascular medications in these 127 patients prior to hospitalization served as a control group. RESULTS: After the educational program, aspirin, clopidogrel, or warfarin was given to 93% of patients compared with 67% in the control group; beta blockers were given to 81% of patients compared with 56% in the control group; ACE inhibitors or ARBs were given to 70% of patients compared with 42% in the control group. Lipid-lowering drugs if dyslipidemia were given to 88% of patients compared with 52% in the control group; calcium channel blockers were given to 18% of patients compared with 24% in the control group. CONCLUSIONS: In patients with CAD, the educational program increased the use of antiplatelet drugs by 26%, beta blockers by 25%, ACE inhibitors or ARBs by 28%, and lipid-lowering drugs by 36%, and decreased the use of calcium channel blockers by 6%.  相似文献   
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