[Influence of the time of myocardial ischemia on the electrocardiographic conduction intervals after surgical correction of aortic valvular stenosis]. / Influência do tempo de isquemia miocárdica nos intervalos electrocardiográficos de condução após correcção cirúrgica de estenose valvular aórtica.

UNLABELLED: The development of conduction disturbances after aortic valve replacement is a well-known complication. Since during the surgical procedure it is necessary to use extracorporeal circulation, it is plausible that the degree of myocardial ischemia (secondary to clamping of the aorta) contributes to the increase of the electrocardiographic conduction intervals. AIM: To understand if the time of myocardial ischemia performed at the surgical correction of valvular aortic stenosis is associated with increased post-operatory electrocardiographic PR, QRS and QT intervals. MATERIAL AND METHODS: 120 individuals were consecutively and retrospectively studied who exclusively underwent aortic valve replacement for aortic valve stenosis, between 2008 and 2010, at Centro Hospitalar de Vila Nova de Gaia/Espinho. Of the various parameters collected, were analysed the time of myocardial ischemia and electrocardiographic PR, QRS and QT corrected for heart rate intervals, at the time of admission and before hospital discharge. Then the value of the difference (variation) between the intervals after and before surgery was calculated. RESULTS: In the sample studied (age 72 ± 10 years, TIM 58 ± 16 minutes), there is insufficient statistical evidence to state that the myocardial ischemia time and the variation of the PR (p=0,108), QRS (p=0,065) and QT corrected for heart rate (p=0,799) are related. CONCLUSIONS: The duration of myocardial ischemia does not influence the electrocardiographic intervals after surgical correction of aortic valve stenosis. However, after surgical intervention, there is an increase in PR and QRS intervals.

Extracorporeal membrane oxygenation in circulatory and respiratory failure - A single-center experience. / Oxigenação por membrana extracorporal na falência circulatória e respiratória ­ experiência de um centro.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) provides mechanical pulmonary and circulatory support for patients with shock refractory to conventional medical therapy. In this study we aim to describe the indications, clinical characteristics, complications and mortality associated with use of ECMO in a single tertiary hospital. METHODS: We conducted a retrospective observational cohort study of all patients supported with ECMO in two different intensive care units (general and cardiac), from the first patient cannulated in April 2011 up to October 2016. RESULTS: Overall, 48 patients underwent ECMO: 29 venoarterial ECMO (VA-ECMO) and 19 venovenous ECMO (VV-ECMO). In VA-ECMO, acute myocardial infarction was the main reason for placement. The most frequent complication was lower limb ischemia and the most common organ dysfunction was acute renal failure. In VV-ECMO, acute respiratory distress syndrome after viral infection was the leading reason for device placement. Access site bleeding and hematologic dysfunction were the most prevalent complication and organ dysfunction, respectively. Almost 70% of ECMO episodes were successfully weaned in each group. Survival to discharge was 37.9% for VA-ECMO and 63.2% for VV-ECMO. In VA-ECMO, the number of inotropic agents was a predictor of mortality. CONCLUSION: Patients with respiratory indications for ECMO experienced better survival than cardiac patients. The need for more inotropic drugs was a predictor of mortality in VA-ECMO. This is the first published record of the overall experience with ECMO in a Portuguese tertiary hospital.