Predictors of Death in Contemporary Adult Patients With Eisenmenger Syndrome: A Multicenter Study.

BACKGROUND: Eisenmenger syndrome is associated with substantial morbidity and mortality. There is no consensus, however, on mortality risk stratification. We aimed to investigate survival and predictors of death in a large, contemporary cohort of Eisenmenger syndrome patients. METHODS: In a multicenter approach, we identified adults with Eisenmenger syndrome under follow-up between 2000 and 2015. We examined survival and its association with clinical, electrocardiographic, echocardiographic, and laboratory parameters. RESULTS: We studied 1098 patients (median age, 34.4 years; range, 16.1-84.4 years; 65.1% female; 31.9% with Down syndrome). The majority had a posttricuspid defect (n=643, 58.6%), followed by patients with a complex (n=315, 28.7%) and pretricuspid lesion (n=140, 12.7%). Over a median follow-up of 3.1 years (interquartile range, 1.4-5.9), allowing for 4361.6 patient-years observation, 278 patients died and 6 underwent transplantation. Twelve parameters emerged as significant predictors of death on univariable analysis. On multivariable Cox regression analysis, only age (hazard ratio [HR], 1.41/10 years; 95% confidence interval [CI], 1.24-1.59; P<0.001), pretricuspid shunt (HR, 1.56; 95% CI, 1.02-2.39; P=0.041), oxygen saturation at rest (HR, 0.53/10%; 95% CI, 0.43-0.65; P<0.001), presence of sinus rhythm (HR, 0.53; 95% CI, 0.32-0.88; P=0.013), and presence of pericardial effusion (HR, 2.41; 95% CI, 1.59-3.66; P<0.001) remained significant predictors of death. CONCLUSIONS: There is significant premature mortality among contemporary adults with Eisenmenger syndrome. We report, herewith, a multivariable mortality risk stratification model based on 5 simple, noninvasive predictors of death in this population.

Real-time simulation of ultrasound refraction phenomena using ray-trace based wavefront construction method.

Ultrasound (US) imaging is one of the most popular techniques used in clinical diagnosis, mainly due to lack of adverse effects on patients and the simplicity of US equipment. However, the characteristics of the medium cause US imaging to imprecisely reconstruct examined tissues. The artifacts are the results of wave phenomena, i.e. diffraction or refraction, and should be recognized during examination to avoid misinterpretation of an US image. Currently, US training is based on teaching materials and simulators and ultrasound simulation has become an active research area in medical computer science. Many US simulators are limited by the complexity of the wave phenomena, leading to intensive sophisticated computation that makes it difficult for systems to operate in real time. To achieve the required frame rate, the vast majority of simulators reduce the problem of wave diffraction and refraction. The following paper proposes a solution for an ultrasound simulator based on methods known in geophysics. To improve simulation quality, a wavefront construction method was adapted which takes into account the refraction phenomena. This technique uses ray tracing and velocity averaging to construct wavefronts in the simulation. Instead of a geological medium, real CT scans are applied. This approach can produce more realistic projections of pathological findings and is also capable of providing real-time simulation.