RESUMO
This study aims to compare the effectiveness of leadless pacemakers (LPs) and transvenous pacemakers and to examine the safety of both methods. We included patients undergoing single-chamber pacemaker implantation, either LP or TVP. Our outcomes were successful implantation rate, major complication, vascular injury, tamponade, and pneumothorax. We performed a double-arm analysis comparing LP versus TVP, with risk ratio (RR) and 95% confidence interval. A total of 10 studies were included in this meta-analysis. Regarding efficacy endpoints, RR revealed no significant difference between the LP and transvenous pacemaker groups in terms of successful rate of implantation (RR = 1.00; P = 0.77). Regarding safety outcomes, LP experienced lower incidence of major complications (RR = 0.47; P = 0.01), infection (RR = 0.24; P = 0.001), and tamponade (RR = 0.36; P = 0.01). There was no significant difference between both groups regarding pneumothorax (RR = 0.35; P = 0.22) and vascular injury (RR = 1.55; P = 0.25). The study findings suggest that both LPs and TVPs have similar effectiveness. Moreover, the incidences of pneumothorax, vascular injuries, and major complications were found to be comparable between the 2 methods. However, LPs were found to have lower rates of infection and tamponade.
RESUMO
Following the decline in Physical Activity (PA) due to COVID-19 restrictions in the form of government mandated lockdowns and closures of public spaces, the modulatory effect of physical exercise on immunity is being heavily revisited. In an attempt to comprehend the wide discrepancy in patient response to COVID-19 and the factors that potentially modulate it, we summarize the findings relating PA to inflammation and immunity. A distinction is drawn between moderate intensity and high intensity physical exercise based on the high lactate production observed in the latter. We hypothesize that, the lactate production associated with high intensity anaerobic exercise is implicated in the modulation of several components of the innate and adaptive immunity. In this review, we also summarize these immunomodulatory effects of lactate. These include increasing serum IL-6 levels, the main mediator of cytokine storms, as well as affecting NK cells, Macrophages, Dendritic cells and cytotoxic T-lymphocytes. The implications of high lactate levels in athletic performance are highlighted where athletes should undergo endurance training to increase VO2 max and minimize lactate production. Tumor models of hypoxia were also reported where lactate levels are elevated leading to increased invasiveness and angiogenesis. Accordingly, the novel lactate blocking strategy employed in cancer treatment is evaluated for its potential benefit in COVID-19 in addition to the readily available beta-blockers as an antagonist to lactate. Finally, we suggest the diagnostic/prognostic purpose of the elevated lactate levels that can be determined through sweat lactate testing. It is the detrimental effect of lactate on immunity and its presence in sweat that qualify it to be used as a potential non-invasive marker of poor COVID-19 outcome.
