Non-Invasive Estimation of Right Atrial Pressure Using a Semi-Automated Echocardiographic Tool for Inferior Vena Cava Edge-Tracking

New ultrasound techniques. Present and future

The present study highlights the advances in ultrasound, especially regarding its clinical applications to critically ill patients. Artificial intelligence (AI) is crucial in automating image interpretation, improving accuracy and efficiency. Software has been developed to make it easier to perform accurate bedside ultrasound examinations, even by professionals lacking prior experience, with automatic image optimization. In addition, some applications identify cardiac structures, perform planimetry of the Doppler wave, and measure the size of vessels, which is especially useful in hemodynamic monitoring and continuous recording. The "strain" and "strain rate" parameters evaluate ventricular function, while "auto strain" automates its calculation from bedside images. These advances, and the automatic determination of ventricular volume, make ultrasound monitoring more precise and faster. The next step is continuous monitoring using gel devices attached to the skin.

Evaluation of an artificial intelligence-based system for echocardiographic estimation of right atrial pressure

Current noninvasive estimation of right atrial pressure (RAP) by inferior vena cava (IVC) measurement during echocardiography may have significant inter-rater variability due to different levels of observers' experience. Therefore, there is a need to develop new approaches to decrease the variability of IVC analysis and RAP estimation. This study aims to develop a fully automated artificial intelligence (AI)-based system for automated IVC analysis and RAP estimation. We presented a multi-stage AI system to identify the IVC view, select good quality images, delineate the IVC region and quantify its thickness, enabling temporal tracking of its diameter and collapsibility changes. The automated system was trained and tested on expert manual IVC and RAP reference measurements obtained from 255 patients during routine clinical workflow. The performance was evaluated using Pearson correlation and Bland-Altman analysis for IVC values, as well as macro accuracy and chi-square test for RAP values. Our results show an excellent agreement (r=0.96) between automatically computed versus manually measured IVC values, and Bland-Altman analysis showed a small bias of [Formula: see text]0.33 mm. Further, there is an excellent agreement ([Formula: see text]) between automatically estimated versus manually derived RAP values with a macro accuracy of 0.85. The proposed AI-based system accurately quantified IVC diameter, collapsibility index, both are used for RAP estimation. This automated system could serve as a paradigm to perform IVC analysis in routine echocardiography and support various cardiac diagnostic applications.

The impact of right atrial pressure on outcomes in patients undergoing TIPS, an ALTA group study

BACKGROUND AND AIMS

Single-center studies in patients undergoing TIPS suggest that elevated right atrial pressure (RAP) may influence survival. We assessed the impact of pre-TIPS RAP on outcomes using the Advancing Liver Therapeutic Approaches (ALTA) database.

APPROACH AND RESULTS

Total 883 patients in ALTA multicenter TIPS database from 2010 to 2015 from 9 centers with measured pre-TIPS RAP were included. Primary outcome was mortality. Secondary outcomes were 48-hour post-TIPS complications, post-TIPS portal hypertension complications, and post-TIPS inpatient admission for heart failure. Adjusted Cox Proportional hazards and competing risk model with liver transplant as a competing risk were used to assess RAP association with mortality. Restricted cubic splines were used to model nonlinear relationship. Logistic regression was used to assess RAP association with secondary outcomes.Pre-TIPS RAP was independently associated with overall mortality (subdistribution HR: 1.04 per mm Hg, 95% CI, 1.01, 1.08, p =0.009) and composite 48-hour complications. RAP was a predictor of TIPS dysfunction with increased odds of post-90-day paracentesis in outpatient TIPS, hospital admissions for renal dysfunction, and heart failure. Pre-TIPS RAP was positively associated with model for end-stage liver disease, body mass index, Native American and Black race, and lower platelets.

CONCLUSIONS

Pre-TIPS RAP is an independent risk factor for overall mortality after TIPS insertion. Higher pre-TIPS RAP increased the odds of early complications and overall portal hypertensive complications as potential mechanisms for the mortality impact.