Abstract Background: diastolic dysfunction has been reported as a cardiovascular effect of hyperthyroidism, and is also supposed to be a cause of heart failure manifestations in the patients with preserved ejection fraction (EF). Methods: for evaluation of diastolic function in hyperthyroid patients and also diastolic Function during performing exercise stress echocardiography, we conducted this study on 26 newly diagnosed hyperthyroid patients compared to 26 healthy subjects as control group. Diastolic function of the patients at rest was assessed using these parameters as follows: left atrium volume index, tricuspid regurgitation (TR) velocity, mitral inflow early diastolic flow (E wave), tissue doppler of mitral annular velocity (e’), E/e’ ratio, and isovolumic relaxation time (IVRT); and during exercise stress echocardiography, we judged diastolic response by measuring E/e’ ratio and TR velocity at the peak of stress in terms of the American Society of Echocardiography guideline. Results: the mean age of the patients was 39.77±12.0 years old and 53.8 % of them were female. Cardiovascular symptoms among the patients were the followings: palpitation (46.2%), exertional dyspnea (19.2%), and atypical chest pain (7.7%). All the patients had normal diastolic function at the time of resting and there was no significant difference in diastolic parameters between the two groups except for IVRT, which was lower in hyperthyroid patients. Interestingly, no patients developed diastolic dysfunction during exercise stress echocardiography. Conclusion: our finding did not support Hyperthyroidsm associated diastolic dysfunction as a cause of exertional intolerance and dyspnea in the patients with preserved EF.

Understanding influencing factors on extubation in cardiac surgery patients has great importance. The aim of this study was to determine the relationship between demographic characteristics, medical and clinical variables as well as extubation time in this patients, in Cardiovascular Center. This research is a casual-comparative study, conducted on 210 adult patients underwent cardiac surgery, in 2018, in Tehran. Study samples were selected by convenience sampling method. The data collection tool was a researcher-made observation checklist that included four sections on patients' demographic characteristics, high risk factors related to the disease, patients' clinical condition in ICU, and clinical variables during surgery. The required data was collected. Study subjects were categorized into two study groups of more than 6 hours mechanical ventilation group and less or equal to 6 hours mechanical ventilation group based on their mechanical ventilation time. Using multivariate analysis test,the factors affecting endotracheal tube extubation were determined. IBM SPSS Statistics software version 21 was used for statistical analysis. Study subjects were 210 post-cardiac surgery patients including 142 males and 68 females with median age of 55. Findings indicated that age, sedation and duration of pulmonary circulation had a significant influence on extubation time in post-cardiac surgery patients. Findings indicated that age, sedation and duration of pulmonary circulation has impact on the process of extubation. Implementation of a precise discontinuation program from mechanical ventilation with considering these factors, are recommended in order to prevent long-term mechanical ventilation as well as reducing days of admission to ICU.