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Dobutamine stress echocardiography is an alternative method to exercise stress echocardiography for the evaluation of ischemia. Recently, the novel speckle tracking imaging derived parameter, myocardial work index, was suggested for the evaluation of cardiac performance and was evaluated during exercise stress echocardiography. In this study, we analyzed the effect of dobutamine on myocardial work index variables during normal dobutamine stress echocardiography. Echocardiography examinations of patients with normal dobutamine stress echocardiography were collected and underwent off-line speckle tracking imaging analysis. Myocardial work index parameters were calculated at each dose of dobutamine and compared. 286 patients underwent dobutamine stress echocardiography during the study period. 102 patients were excluded due to pre-existed coronary artery disease or ischemia at dobutamine stress echocardiography. 65 patients were excluded due to suboptimal image quality unsuitable for speckle tracking imaging analysis. The remaining 119 patients with normal results were included. The global work index decreased from 2393.3 to 1864.7 mmHg%, p < 0.0004. Global constructive work decreased from 2681.7 to 2152.6 mmHg%, p = 0.001. Global wasted work increased from 78.8 to 128.3 mmHg%, p < 0.003. Global work efficacy decreased from 96.1 to 91.9%, p < 0.00001. Global strain increased from—19.6 to − 23.7%, p < 0.00001. Dobutamine stress echocardiography results in a decrease of all specific myocardial work index parameters even in normal subjects. Only global myocardial strain improved.

INTRODUCTION: Point-of-care ultrasound (POCUS) is becoming increasingly important for rapid assessment and diagnosis in a variety of clinical situations. With the ongoing COVID-19 pandemic, the aim of this study is to determine whether a virtual POCUS session can improve learner competency in assessing left ventricular (LV) systolic function. METHODS: An hour long session, involving a short lecture and fourteen practice questions was created. The questions consisted of cardiac ultrasound clips from real patients, evaluated by three POCUS experts. For each clip, LV systolic function was classified as hyperdynamic, normal, reduced, or severely reduced. The session was given separately to a group of interns (n1=30) and a group of senior residents (n2=39) virtually via Zoom. Series of clips were shown as the lecture progressed and participants recorded their answers as either hyperdynamic, normal, reduced, or severely reduced using the polling feature within the Zoom platform. Effect size as the percent of correct responses was calculated. Data was analyzed using SPSS software with independent t-test and paired t-test analysis with a level of statistical significance as p ≤0.05. Results: The intern group had a mean score of 69.9% [SD 21.8%] and the resident group had a mean score of 74.2% [SD 21.5%]. All participants achieved a mean score of 66.6% [SD 26.0%] during the first half of the lecture, which then improved to 77.6% [SD 14.2%] in the second half [p value 0.547]. Both groups showed similar overall trends, although these were not statistically significant. When combined, extremes of LV function (hyperdynamic and severely reduced) were better recognized than more subtle differences (reduced and normal) [81.4%±18.1 vs 55.2±15.9; p = 0.001] overall. Conclusion: Compared to the conventional in-person approach, this study highlights the potential for virtual didactic sessions in POCUS training with impressive results when recognizing extreme cardiac findings.

PurposeDobutamine stress echocardiography is an alternative method to exercise stress echocardiography for the evaluation of ischemia. Recently, the novel speckle tracking imaging derived parameter, myocardial work index, was suggested for the evaluation of cardiac performance and was evaluated during exercise stress echocardiography. In this study we analyzed the effect of dobutamine on myocardial work index variables during normal dobutamine stress echocardiography.MethodsEchocardiography examinations of patients with normal dobutamine stress echocardiography were collected and underwent off-line speckle tracking imaging analysis. Myocardial work index parameters were calculated at each dose of dobutamine and compared.Results286 patients underwent dobutamine stress echocardiography during the study period. 102 patients were excluded due to pre-existed coronary artery disease or ischemia at dobutamine stress echocardiography. 65 patients were excluded due to suboptimal image quality unsuitable for speckle tracking imaging analysis. The remaining 119 patients with normal results were included. The global work index decreased from 2393.3 to 1864.7 mmHg', p < 0.0004. Global constructive work decreased from 2681.7 to 2152.6 mmHg', p = 0.001. Global wasted work increased from 78.8 to 128.3%, p < 0.003. Global work efficacy decreased from 96.1 to 91.9%, p < 0.00001. Global strain increased from – 19.6 to -23.7%, P < 0.00001. Conclusion. Dobutamine stress echocardiography results in a decrease of all specific myocardial work index parameters even in normal subjects. Only global myocardial strain improved.

Introduction: Aortic-valve replacement (AVR) is an effective therapy for patients with severe symptomatic aortic stenosis (AS) but the appropriate timing of intervention for asymptomatic patients with severe AS remains controversial. Increased mortality associated with the onset of symptoms challenges the conventional “watchful waiting” strategy followed for this subset of patients. An early intervention may be warranted, however the data supporting this hypothesis is small. Our aim was to perform meta-analysis looking at outcomes of early surgical AVR (SAVR) in asymptomatic severe AS patients with preserved LVEF. Methods: Electronic databases were searched for studies comparing early SAVR and conventional treatment in patients with asymptomatic severe AS and normal LV function. The primary outcome of interest was all cause mortality. Secondary outcome was heart failure hospitalization. Random-effects model was used to estimate the pooled risk ratio (RR), and 95% confidence interval (CI) using Revman 5.4.1. Subgroup analysis stratified by study design was performed. Heterogeneity was assessed by Higgins I 2 statistic. Results: We found total of 8 studies (2 RCTs; 6 observational) from which 2669 patients with asymptomatic severe AS were identified. 1354 underwent SAVR and 1315 were managed conservatively. The mean age was 68 years with mean follow up duration of 4.8±2 years. There was statistically significant reduction in all-cause mortality (RR: 0.37; CI: 0.27-0.50; p<0.05; I2 = 68%) and heart failure hospitalization (RR: 0.24; CI: 0.16-0.36; p<0.05; I2 = 0%) among patients who underwent AVR compared with conservative treatment with subgroup analysis by study design showing similar trends. Conclusion: Our meta-analysis shows that compared with conventional treatment strategy, early SAVR in asymptomatic patients with severe AS is associated with improved long-term outcomes notably reduced all cause mortality and heart failure hospitalizations.