IJCS | Volume 31, Nº3, May/ June 2018

283 Table 1 - Components of the PICO* strategy P Patient with acute myocardial infarction I Impedance Cardiography C Swan-Ganz catheter O Hemodynamic variables *Adapted from Lima, 2009. 6 Silva et al. Impedance cardiography in myocardial infarction International Journal of Cardiovascular Sciences. 2018;31(3)282-289 Review Article it is a noninvasive, portable, easy to handle and has good reproducibility and, therefore, is viable for clinical practice and epidemiological studies. Impedance cardiography has been increasingly used as a prognostic indicator in acute myocardial infarction. 3 Objectives - To verify the accuracy of the use of impedance cardiography in patientswith acutemyocardial infarction. - To compare the indications of the impedance cardiography with the Swan-ganz catheter in patients with acute myocardial infarction. Method It was a descriptive, retrospective research, based on a quantitative approach, conducted by means of literature review. For the survey of articles in the literature, a search was conducted in the following databases: LatinAmerican and Caribbean Literature in Heath Sciences (LILACS), Medical Literature Analysis and Retrieval Sistem on-line (Medline), Cumulative Index to Nursing & Allied Health Literature (CINAHL) and COCHRANE LIBRARY. The electronic searchwas guided by the PICO strategy. The PICO acronym stands for: Patient, Intervention, Comparison and Outcomes. 5 Table 1 presents the components of the PICO strategy. The collection of data occurred in the period from January to August 2015. The following controlled descriptors were used to find the articles in databases: myocardial infarction, cardiography impedance, catheterization, Swan Ganz, invasive hemodynamic monitoring and hemodynamics. The composition of the sample met the inclusion criteria: Articles in Portuguese, English and Spanish; Articles that compared bioimpedance cardiography and invasive hemodynamic monitoring; Population: adult patients (aged older than 18 years) in critical condition; Articles published between 2005 and 2015. And as exclusion criteria: Articles not available in full-text; Studies conducted with animals; Articles that compared bioimpedance cardiographywith other methods; Revision articles. For data collection, an instrument was developed composed of data related to the journal (title, area, database, country, language, year of publication), the authorship (number of authors, profession of the authors) and to the study (place of research, sample identification, design, type of participants, type of publication, results and conclusions). In the search, 108 articles were found inMEDLINE (02 articles were added due to similarity), 126 in CINAHL, 11 in LILACS, and 62 in COCHRANE, totaling 307 articles in an initial sample. Following the eligibility criteria, 259 (84.36%) articles were excluded. A dynamic reading of the 48 (15.63%) remaining articles was taken, and 38 (12.37%) articles were excluded since they were related to heart failure or compared bioimpedance cardiography with other methods. 10 articles were absorbed from the initial sample in order to develop this study. Results Ten articles were selected for review, among which eight (80%) were found in the Medline database and two (20%) in Cochrane. The USA and Lithuania were the countries that most published on the proposed outcome, totaling 60% of the results. It was found no indexed publication in Brazilian journals (Chart 1). It was shown that 80% of the articles were developed by doctors, 10% by nurses and 10% by professionals of both categories (Chart 2). Discussion In accordance with this study’s objective, which refers to the identification of the accuracy of impedance cardiography compared to the Swan-Ganz catheter, this revision was concerned to elect clinical trial articles, considering their scientific magnitude to the scientific society, in addition to checking the journal’s origin and its scientific relevance. Impedance cardiography (ICG) is a reliable method for hemodynamic monitoring in cases of acutemyocadial infarction without complications. 7