RESUMEN
We sought to evaluate the potential clinical role of 4D-flow cardiac magnetic resonance (CMR)-derived energetics and flow parameters in a cohort of patients' post-Fontan palliation. In patients with Fontan circulation who underwent 4D-Flow CMR, streamlines distribution was evaluated, as well a 4D-flow CMR-derived energetics parameters as kinetic energy (KE) and energy loss (EL) normalized by volume. EL/KE index as a marker of flow efficiency was also calculated. Cardiopulmonary exercise test (CPET) was also performed in a subgroup of patients. The population study included 55 patients (mean age 22 ± 11 years). The analysis of the streamlines revealed a preferential distribution of the right superior vena cava flow for the right pulmonary artery (62.5 ± 35.4%) and a mild preferential flow for the left pulmonary artery (52.3 ± 40.6%) of the inferior vena cave-pulmonary arteries (IVC-PA) conduit. Patients with heart failure (HF) presented lower IVC/PA-conduit flow (0.75 ± 0.5 vs 1.3 ± 0.5 l/min/m2, p = 0.004) and a higher mean flow-jet angle of the IVC-PA conduit (39.2 ± 22.8 vs 15.2 ± 8.9, p < 0.001) than the remaining patients. EL/KE index correlates inversely with VO2/kg/min: R: - 0.45, p = 0.01 peak, minute ventilation (VE) R: - 0.466, p < 0.01, maximal voluntary ventilation: R:0.44, p = 0.001 and positively with the physiological dead space to the tidal volume ratio (VD/VT) peak: R: 0.58, p < 0.01. From our data, lower blood flow in IVC/PA conduit and eccentric flow was associated with HF whereas higher EL/KE index was associated with reduced functional capacity and impaired lung function. Larger studies are needed to confirm our results and to further improve the prognostic role of the 4D-Flow CMR in this challenging population.
Asunto(s)
Prueba de Esfuerzo , Procedimiento de Fontan , Cardiopatías Congénitas , Arteria Pulmonar , Humanos , Femenino , Masculino , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/fisiopatología , Adulto Joven , Prueba de Esfuerzo/métodos , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/fisiopatología , Adolescente , Adulto , Imagen por Resonancia Cinemagnética/métodos , Niño , Vena Cava Superior/diagnóstico por imagen , Velocidad del Flujo Sanguíneo/fisiología , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/cirugía , Vena Cava Inferior/diagnóstico por imagenAsunto(s)
Anticoagulantes/efectos adversos , Infecciones por Coronavirus/terapia , Fibrinolíticos/efectos adversos , Hemorragia/inducido químicamente , Neumonía Viral/terapia , Trombosis/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Betacoronavirus/patogenicidad , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Femenino , Fibrinolíticos/administración & dosificación , Hemorragia/epidemiología , Interacciones Huésped-Patógeno , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/virología , Prevalencia , Factores de Riesgo , SARS-CoV-2 , Suiza/epidemiología , Trombosis/epidemiología , Trombosis/virología , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
Collapsibility of caval vessels and stroke volume and pulse pressure variations (SVV, PPV) are used as indicators of volume responsiveness. Their behavior under increasing airway pressures and changing right ventricular afterload is incompletely understood. If the phenomena of SVV and PPV augmentation are manifestations of decreasing preload, they should be accompanied by decreasing transmural right atrial pressures. Eight healthy pigs equipped with ultrasonic flow probes on the pulmonary artery were exposed to positive end-expiratory pressure of 5 and 10 cmH2O and three volume states (Euvolemia, defined as SVV < 10%, Bleeding, and Retransfusion). SVV and PPV were calculated for the right and PPV for the left side of the circulation at increasing inspiratory airway pressures (15, 20, and 25 cmH2O). Right ventricular afterload was assessed by surrogate flow profile parameters. Transmural pressures in the right atrium and the inferior and superior caval vessels (IVC and SVC) were determined. Increasing airway pressure led to increases in ultrasonic surrogate parameters of right ventricular afterload, increasing transmural pressures in the right atrium and SVC, and a drop in transmural IVC pressure. SVV and PPV increased with increasing airway pressure, despite the increase in right atrial transmural pressure. Right ventricular stroke volume variation correlated with indicators of right ventricular afterload. This behavior was observed in both PEEP levels and all volume states. Stroke volume variation may reflect changes in right ventricular afterload rather than changes in preload.NEW & NOTEWORTHY Stroke volume variation and pulse pressure variation are used as indicators of preload or volume responsiveness of the heart. Our study shows that these variations are influenced by changes in right ventricular afterload and may therefore reflect right ventricular failure rather than pure volume responsiveness. A zone of collapse detaches the superior vena cava and its diameter variation from the right atrium.
Asunto(s)
Respiración Artificial , Vena Cava Superior , Animales , Presión Sanguínea , Hemodinámica , Volumen Sistólico , Porcinos , Función Ventricular DerechaRESUMEN
BACKGROUND: The majority of prevalence studies on deep vein thrombosis (DVT) in severe COVID-19 patients are retrospective with DVT assessment based on clinical suspicion. Our aim was to prospectively and systematically estimate the occurrence of DVT in critically-ill mechanically-ventilated patients, and to identify potential risk factors for DVT occurrence and mortality. METHODS: All patients with COVID-19 admitted to our 45 beds in the Intensive Care Unit (ICU) between March 6, 2020, and April 18, 2020, requiring invasive ventilatory support were daily screened for DVT with lower extremities and jugular veins ultrasonography. Univariate and multivariable logistic regression models were performed in order to identify predictors of DVT and mortality. RESULTS: Seventy-six patients were included in the final analysis (56 men, mean age 67 years, median SOFA=7 points, median SAPS II=41 points, median PaO