The reported incidence of venous thromboembolism (VTE) in patients with human immunodeficiency virus (HIV) infection has ranged from 0.25 to 0.96% in clinical studies, but up to 17% at autopsy. A preliminary analysis at our hospital suggested that the frequency of VTE among HIV-positive individuals might be higher than previously reported. To further evaluate this issue, we performed a retrospective study of patients with a diagnosis of VTE and/or HIV infection discharged from our hospital between July 1, 1998 and June 30, 1999. A total of 13,496 patients were discharged during the year of the study. There were 244 patients with VTE and 362 who were HIV-positive. Ten of the 244 patients with VTE were HIV-positive (4.1%). The frequency of VTE among HIV-positive individuals was 10/362 (2.8%) compared to 234/13134 (1.8%) in the non-HIV-positive group, but the difference is not statistically significant. However, in patients under age 50, the frequencies were significantly different: 10/302 (3.31%) versus 35/6594 (0.53%), respectively (p < 0.0001). The frequency of VTE in HIV-positive patients less than 50 years old (3.31%) was greater than in HIV-positive patients over 50 years of age (0/60), but the difference did not reach statistical significance. In contrast, in the non-HIV-positive group, VTE was significantly more frequent in those 50 and older compared to younger patients (3.04% versus 0.53%, p = 0.0001). Statistical analysis indicated that the direction of association between age and diagnosis of VTE differed for HIV-positive patients versus non-HIV-positive patients. Our results suggest that HIV-positive patients under age 50 are at increased risk for VTE compared with non-HIV-positive individuals.

Purpose The impact of metabolic syndrome (MetS) on recurrence of atrial fibrillation (AF) after catheter ablation remains uncertain. We conducted a meta-analysis to summarize the relative risks (RR) of AF recurrence after catheter ablation in patients with vs. without MetS and its components. Methods Among 839 articles identified from PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials, we included 23 studies with a total of 12,924 patients (7,594 with paroxysmal AF and 5,330 with nonparoxysmal AF) for analysis. Five of these had complete information on MetS components. Variables assessed comprised study design and population characteristics, AF ablation methods, use of anti-arrhythmic drugs, AF recurrence ascertainment methods, adjustment variables, and other quality indicators. Results Our meta-analysis found an elevated risk of AF recurrence after ablation in patients with vs. without MetS (pooled RR, 1.63; 95 % confidence interval (CI), 1.25–2.12). Among components of MetS, hypertension was a predictor of AF post-ablation recurrence in studies without adjustment for other MetS components (RR, 1.62; 95 % CI, 1.23–2.13) but not in those adjusting for two or more additional MetS components (RR, 1.03; 95 % CI, 0.88–1.20). There was a borderline association between overweight/obesity and AF recurrence after ablation (RR, 1.27; 95 % CI, 0.99–1.64). Conclusions MetS is associated with an increased risk of AF recurrence after catheter ablation. Further study of the MetS and its components as determinants of AF risk could help refine patient selection and improve procedural outcomes.

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Effects of age on the pulmonary vascular responses to histamine (HIST), norepinephrine (NE), 5-hydroxytryptamine (5-HT), and KCl were studied in isolated, perfused lungs from juvenile (7-wk-old), adult (14-wk-old), and mature adult (28-wk-old) normoxic rats and compared with age-matched rats exposed to chronic hypoxia for either 14 or 28 days. Chronic hypoxia changed vasoconstriction to HIST and NE to vasodilation in lungs from juvenile and adult rats. Mature adult lungs only vasoconstricted to these amines in both control and hypoxic animals. Pressor responses to 5-HT were not affected by chronic hypoxia regardless of age group. Pressor responses to KCl were also not altered by hypoxia, but lungs from older rats showed greater control responsiveness to KCl compared with lungs from juveniles. Only lungs from juvenile animals developed significant elevations of base-line resistance as a result of hypoxic exposure. To investigate the contribution of H1-, H2-, and beta-receptors in these changes, we employed chlorpheniramine, metiamide, and propranolol, respectively, as blocking agents in another series of experiments. Chlorpheniramine either reduced vasoconstriction or increased vasodilation to HIST in lungs from both control and hypoxic animals, whereas metiamide was without effect. Propranolol either increased vasoconstriction or reversed vasodilation to HIST and NE in all lungs studied. The present data demonstrate the important interaction between chronic hypoxia and age that can alter pulmonary vascular tone and reactivity. The inverse relationship between age and elevation of pulmonary vascular resistance after chronic hypoxic exposure may be the key element that changes pulmonary vascular reactivity observed during hypoxia.(ABSTRACT TRUNCATED AT 250 WORDS)

levels of lactate dehydrogenase, immeasurable low levels of haptoglobin and very high levels of free haemoglobin in plasma. Coombs test was negative and no erythrocyte antibodies could be detected. Schistocytes could not be identified at blood microscopy. Biochemical screening revealed no antineutrophil cytoplasmic antibodies and the levels of immunoglobulins and complement factors were normal. The number of blood eosinophils was normal. The platelet number decreased from 422 Â 10 9