ABSTRACT CONTEXT AND OBJECTIVE: Cardiac arrest is associated with high morbidity and mortality and imposes a significant burden on the healthcare system. Management of cardiac arrest patients is complex and involves approaches with multiple interventions. Here, we aimed to summarize the available evidence regarding the interventions used in cardiac arrest cases. DESIGN AND SETTING: Review of systematic reviews (SRs), conducted in the Discipline of Evidence-Based Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo. METHODS: A systematic search was conducted to identify all Cochrane SRs that fulfilled the inclusion criteria. Titles and abstracts were screened by two authors. RESULTS: We included nine Cochrane SRs assessing compression techniques or devices (three SRs), defibrillation (two SRs) and other interventions (two SRs on hypothermia interventions, one on airway management and one on pharmacological intervention). The reviews included found qualities of evidence ranging from unknown to high, regarding the benefits of these interventions. CONCLUSION: This review included nine Cochrane systematic reviews that provided a diverse range of qualities of evidence (unknown to high) regarding interventions that are used in management of cardiac arrest. High-quality evidence was found by two systematic reviews as follows: (a) increased survival until hospital discharge with continuous compression, compared with interrupted chest compression, both administered by an untrained person and (b) no difference regarding the return of spontaneous circulation, comparing aminophylline and placebo, for bradyasystolic patients under cardiac arrest. Further studies are needed in order to reach solid conclusions.

ABSTRACT BACKGROUND: Aortic valve stenosis is the most common type of valvular heart disease in the USA and Europe. Aortic valve stenosis is considered similar to atherosclerotic disease. Some studies have evaluated statins for aortic valve stenosis. OBJECTIVES: To evaluate the effectiveness and safety of statins in aortic valve stenosis. METHODS: Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS - IBECS, Web of Science and CINAHL Plus. These databases were searched from their inception to 24 November 2015. We also searched trials in registers for ongoing trials. We used no language restrictions. Selection criteria: Randomized controlled clinical trials (RCTs) comparing statins alone or in association with other systemic drugs to reduce cholesterol levels versus placebo or usual care. Data collection and analysis: Primary outcomes were severity of aortic valve stenosis (evaluated by echocardiographic criteria: mean pressure gradient, valve area and aortic jet velocity), freedom from valve replacement and death from cardiovascular cause. Secondary outcomes were hospitalization for any reason, overall mortality, adverse events and patient quality of life. Two review authors independently selected trials for inclusion, extracted data and assessed the risk of bias. The GRADE methodology was employed to assess the quality of result findings and the GRADE profiler (GRADEPRO) was used to import data from Review Manager 5.3 to create a 'Summary of findings' table. MAIN RESULTS: We included four RCTs with 2360 participants comparing statins (1185 participants) with placebo (1175 participants). We found low-quality evidence for our primary outcome of severity of aortic valve stenosis, evaluated by mean pressure gradient (mean difference (MD) -0.54, 95% confidence interval (CI) -1.88 to 0.80; participants = 1935; studies = 2), valve area (MD -0.07, 95% CI -0.28 to 0.14; participants = 127; studies = 2), and aortic jet velocity (MD -0.06, 95% CI -0.26 to 0.14; participants = 155; study = 1). Moderate-quality evidence showed no effect on freedom from valve replacement with statins (risk ratio (RR) 0.93, 95% CI 0.81 to 1.06; participants = 2360; studies = 4), and no effect on muscle pain as an adverse event (RR 0.91, 95% CI 0.75 to 1.09; participants = 2204; studies = 3; moderate-quality evidence). Low- and very low-quality evidence showed uncertainty around the effect of statins on death from cardiovascular cause (RR 0.80, 95% CI 0.56 to 1.15; participants = 2297; studies = 3; low-quality evidence) and hospitalization for any reason (RR 0.84, 95% CI 0.39 to 1.84; participants = 155; study = 1; very low-quality evidence). None of the four included studies reported on overall mortality and patient quality of life. AUTHORS CONCLUSIONS: Result findings showed uncertainty surrounding the effect of statins for aortic valve stenosis. The quality of evidence from the reported outcomes ranged from moderate to very low. These results give support to European and USA guidelines (2012 and 2014, respectively) that so far there is no clinical treatment option for aortic valve stenosis.

No mundo ocidental, a estenose da valva aórtica calcificada é a forma mais comum de doença cardíaca valvar, afetando até 3% dos adultos com idade acima de 75 anos. É uma doença gradual e progressiva, caracterizada por uma longa fase assintomática, podendo durar várias décadas, seguida de uma curta fase sintomática associada à restrição grave do orifício da valvar. A investigação sobre o tratamento da estenose da valva aórtica ainda está em curso. Desta forma, acredita-se que a calcificação da estenose da valva aórtica seja semelhante ao processo de aterosclerose que ocorre na doença arterial coronariana. Estudos recentes têm sugerido que a redução do colesterol pelo do uso das estatinas pode ter um efeito salutar sobre a progressão da estenose da valva aórtica

In the Western world, calcified aortic valve stenosis is the most common form of valvular heart disease, affecting up to 3% of adults over the age of 75 years. It is a gradually progressive disease, characterized by a long asymptomatic phase that may last for several decades, followed by a short symptomatic phase associated with severe restriction of the valve orifice. Investigations on treatments for aortic valve stenosis are still in progress. Thus, it is believed that calcification of aortic valve stenosis is similar to the process of atherosclerosis that occurs in coronary artery disease. Recent studies have suggested that cholesterol lowering through the use of statins may have a salutary effect on the progression of aortic valve stenosis