Incidence of Early Atrial Fibrillation After Transcatheter versus Surgical Aortic Valve Replacement: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Post-operative atrial fibrillation (POAF) is common after aortic valve replacement (AVR) and is associated with worse outcomes. We performed a meta-analysis of randomized controlled trials comparing Surgical Aortic Valve Replacement (SAVR) and Transcatheter Aortic Valve Replacement (TAVR) for incidence of POAF at 30 days. METHODS: We searched databases from 1/1/1990 to 1/1/2020 for randomized studies comparing TAVR and SAVR. POAF was defined as either worsening or new-onset atrial fibrillation. Random effects model was used to estimate the risk of POAF with TAVR vs SAVR in all trials, and in subgroups (low, intermediate, high risk, and in self-expandable vs balloon expandable valves). Sensitivity analysis was performed including only studies reporting new-onset atrial fibrillation. RESULTS: Seven RCTs were identified that enrolled 7,934 patients (3,999 to TAVR and 3,935 to SAVR). The overall incidence of POAF was 9.7% after TAVR and 33.3% after SAVR. TAVR was associated with a lower risk of POAF compared with SAVR (OR 0.21 [0.18-0.24]; P < 0.0001). Compared with SAVR, TAVR was associated with a significantly lower risk of POAF in the high-risk cohort (OR 0.37 [0.27-0.49]; P < 0.0001), in the intermediate-risk cohort (OR 0.23 [0.19-0.28]; P < 0.0001), low-risk cohort (OR 0.13 [0.10-0.16]; P < 0.0001). Sensitivity analysis of 4 trials including only new-onset POAF showed similar summary estimates (OR 0.21, 95% CI [0.18-0.25]; P< 0.0001). CONCLUSIONS: TAVR is associated with a significantly lower risk of post-operative atrial fibrillation compared with SAVR in all strata. Further studies are needed to identify the contribution of post-operative atrial fibrillation to the differences in clinical outcomes after TAVR and SAVR.

Air-water partitioning of 222Rn and its dependence on water temperature and salinity.

Radon is useful as a tracer of certain geophysical processes in marine and aquatic environments. Recent applications include detection of groundwater discharges into surface waters and assessment of air/sea gas piston velocities. Much of the research performed in the past decade has relied on continuous measurements made in the field using a radon stripping unit connected to a radon-in-air detection system. This approach assumes that chemical equilibrium is attained between the water and gas phases and that the resulting air activity can be multiplied by a partition coefficient to obtain the corresponding radon-in-water activity. We report here the results of a series of laboratory experiments that describes the dependence of the partition coefficient upon both water temperature and salinity. Our results show that the temperature dependence for freshwater closely matches results that were previously available. The salinity effect, however, has largely been ignored and our results show that this can result in an overestimation of radon concentrations, especially in cooler, more saline waters. Related overestimates in typical situations range between 10 (warmer less saline waters) and 20% (cooler, more saline waters).

Glucocorticoid use, other associated factors, and the risk of tuberculosis.

OBJECTIVE: To evaluate the association of glucocorticoids and other purported risk factors with the development of tuberculosis. METHODS: We conducted a case-control study of tuberculosis cases identified during 1990-2001 using the General Practice Research Database in the United Kingdom. Cases were patients with a first time diagnosis of tuberculosis accompanied by at least 6 months of treatment with at least 3 different tuberculosis medications. Up to 4 controls were matched to each case on age, sex, the practice attended by the case, index date, and amount of prior computerized records. RESULTS: The study encompassed 497 new cases of tuberculosis and 1,966 controls derived from 16,629,041 person-years at risk (n = 2,757,084 persons). The adjusted odds ratio (OR) of tuberculosis for current use of a glucocorticoid compared with no use was 4.9 (95% confidence interval [95% CI] 2.9-8.3). The adjusted ORs for use of <15 mg and > or =15 mg of prednisone or its equivalent daily dose were 2.8 (95% CI 1.0-7.9) and 7.7 (95% CI 2.8-21.4), respectively. Adjusted ORs of tuberculosis were 2.8 for patients with a body mass index (BMI) <20 compared with normal BMI; 1.6 for current smokers compared with nonsmokers; and 3.8, 3.2, 2.0, and 1.4 for those with history of diabetes, emphysema, bronchitis, and asthma, respectively, compared with those without such history (all P values <0.05). CONCLUSION: These results indicate that patients treated with glucocorticoids have an increased risk of developing tuberculosis, independent of other risk factors. Low adiposity, diabetes, current smoking, and obstructive pulmonary disorders are also important independent risk factors for tuberculosis.

The national cholesterol education program diet vs a diet lower in carbohydrates and higher in protein and monounsaturated fat: a randomized trial.

BACKGROUND: In the United States, obesity is a major clinical and public health problem causing diabetes, dyslipidemia, and hypertension, as well as increasing cardiovascular and total mortality. Dietary restrictions of calories and saturated fat are beneficial. However, it remains unclear whether replacement of saturated fat with carbohydrates (as in the US National Cholesterol Education Program [NCEP] diet) or protein and monounsaturated fat (as in our isocaloric modified low-carbohydrate [MLC] diet, which is lower in total carbohydrates but higher in protein, monounsaturated fat, and complex carbohydrates) is optimal. METHODS: We randomized 60 participants (29 women and 31 men) to the NCEP or the MLC diet and evaluated them every 2 weeks for 12 weeks. They were aged 28 to 71 years (mean age, 44 years in the NCEP and 46 years in the MLC group). A total of 36% of participants from the NCEP group and 35% from the MLC group had a body mass index (calculated as weight in kilograms divided by the square of height in meters) greater than 27. The primary end point was weight loss, and secondary end points were blood lipid levels and waist-to-hip ratio. RESULTS: Weight loss was significantly greater in the MLC (13.6 lb) than in the NCEP group (7.5 lb), a difference of 6.1 lb (P = .02). There were no significant differences between the groups for total, low density, and high-density lipoprotein cholesterol, triglycerides, or the proportion of small, dense low-density lipoprotein particles. There were significantly favorable changes in all lipid levels within the MLC but not within the NCEP group. Waist-to-hip ratio was not significantly reduced between the groups (P = .27), but it significantly decreased within the MLC group (P = .009). CONCLUSIONS: Compared with the NCEP diet, the MLC diet, which is lower in total carbohydrates but higher in complex carbohydrates, protein, and monounsaturated fat, caused significantly greater weight loss over 12 weeks. There were no significant differences between the groups in blood lipid levels, but favorable changes were observed within the MLC diet group.

Effect of cigar smoking on endothelium-dependent brachial artery dilation in healthy young adults.

BACKGROUND: Cigar smoking has become a quickly growing trend among teenagers, women, and young adults. The objective was to explore whether cigar smoking affects flow-mediated vasodilation in healthy, non-smoking young adults. METHODS: This was a prospective randomized trial with open design. It was performed in a cardiology teaching program in a private community hospital that serves as a major referral center within the greater Miami area. Apparently healthy, non-smoking young adult cardiology trainees and staff between the ages of 20 and 45 years were randomly assigned to a cigar smoking group (n = 15) or a control group (n = 14). The main outcome measures were the difference in percent diameter increase in the brachial artery after reactive hyperemia and sublingual nitroglycerin between members of the cigar smoking and control groups at baseline, measured after cigar smoking, and at 5 hours. RESULTS: Twenty-nine participants were randomized. Percent diameter increase in the brachial artery was measured with the use of high-resolution ultrasonography. Baseline percent diameter increase after reactive hyperemia and sublingual nitroglycerin was similar in both groups (6.2% vs 6.7%, P = .4 and 22% vs 23%, P = .5, respectively). We observed a 2.5% increase in brachial artery diameter with hyperemia after cigar smoking compared with a 9.4% increase in the control group, P = .045. Values after nitroglycerin were similar between groups, P = .2. Between-group analysis showed no significant difference in percent dilation after reactive hyperemia at 5 hours, P = .4, but a significant difference was seen after sublingual nitroglycerin, P = .02. CONCLUSIONS: These data are compatible with the possibility that cigar smoking may have an acute effect on endothelium-dependent, flow-mediated brachial artery dilation and do not support the possibility of an immediate effect on endothelium-independent vasodilation. Taken together, these results suggest that cigars are not an innocuous alternative to cigarette smoking.