[Lung ultrasound promising method for assessing acute dyspnea and monitoring decompensated heart failure]. / Lungultraljud ­ en uppseglande metod vid dyspné och hjärtsvikt.

Ultrasound plays an important role in several medical fields. The heart was the first organ for which ultrasound gained clinical utility, followed by obstetric and gynecological applications. Shortly thereafter, abdominal organs and blood vessels became targets for ultrasound examination. The lung was long considered inaccessible for ultrasound due to its high air content. Work since the 1990s has however established a role for lung ultrasound, in leveraging several technical artefacts generated in the normal lung and in conditions with reduced air content, to allow rapid diagnosis of interstitial fluid accumulation, pneumothorax, pneumonia among others. In this article, we provide an overview of the potential of lung ultrasound, particularly as a promising method for assessment of patients presenting with acute dyspnea in the emergency department and for monitoring residual fluid in patients with decompensated heart failure. We also discuss limitations and caveats of the method.

Left ventricular longitudinal wall fractional shortening accurately predicts longitudinal strain in critically ill patients with septic shock.

BACKGROUND: Left ventricular longitudinal strain (LVLS) may be a sensitive indicator of left ventricular (LV) systolic function in patients with sepsis, but is dependent on high image quality and analysis software. Mitral annular plane systolic excursion (MAPSE) and the novel left ventricular longitudinal wall fractional shortening (LV-LWFS) are bedside echocardiographic indicators of LV systolic function that are less dependent on image quality. Both are sparsely investigated in the critically ill population, and may potentially be used as surrogates for LVLS. We assessed if LVLS may be predicted by LV-LWFS and MAPSE in patients with septic shock. We also assessed the repeatability and inter-rater agreement of LVLS, LV-LWFS and MAPSE measurements. RESULTS: 122 TTE studies from 3 echocardiographic data repositories of patients admitted to ICU with septic shock were retrospectively assessed, of which 73 were suitable for LVLS analysis using speckle tracking. The correlations between LVLS vs. LV-LWFS and LVLS vs. MAPSE were 0.89 (p < 0.001) and 0.81 (p < 0.001) with mean squared errors of 5.8% and 9.1%, respectively. Using the generated regression equation, LV-LWFS predicted LVLS with a high degree of accuracy and precision, with bias and limits of agreement of -0.044 ± 4.7% and mean squared prediction error of 5.8%. Interobserver repeatability was good, with high intraclass correlation coefficients (0.96-0.97), small bias and tight limits of agreement (≤ 4.1% for all analyses) between observers for all measurements. CONCLUSIONS: LV-LWFS may be used to estimate LVLS in patients with septic shock. MAPSE also performed well, but was slightly inferior compared to LV-LWFS in estimating LVLS. Feasibility of MAPSE and LV-LWFS was excellent, as was interobserver repeatability.