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Detection of intracardiac shunts using CT Coronary Angiography (CTCA) is currently based on anatomical demonstration of defects. We assessed a novel technique using a standard CTCA test bolus in detecting shunts independent of anatomical assessment and to provide an estimate of Qp/Qs. We retrospectively reviewed 51 CTCAs: twenty-one from patients with known simple left to right intracardiac shunts with contemporaneous functional assessment (using CMR) within 6 months, 20 controls with structurally normal hearts, and 10 patients with shunt repairs. From the dynamic acquisition of a test bolus, we measured mean Hounsfield Units (HU) in various anatomical structures. We created time/density curves from the test bolus data, and calculated disappearance time (DT) from the ascending aorta (deriving a Qp/Qs), peak ascending aortic HU, and mean coefficient of variation of the arterial curves, and compared these with the Qp/Qs from the respective CMR. Patients with intracardiac shunts had significantly higher test bolus derived Qp/Qs compared with both the controls, and the repaired shunt comparator group. There was a very strong agreement between the test bolus derived Qp/Qs, and Qp/Qs as measured by CMR (Intraclass correlation 0.89). Mean bias was 0.032 ​± ​0.341 (95% limits of agreement −0.64 to 0.70). Interobserver, and intraobserver agreement of the disappearance time was excellent (0.99, 0.99 (reader 1) and 1.00 (reader 2) respectively). In this proof-of-concept study, we demonstrate a novel technique to detect, and to estimate severity of left to right intracardiac shunts on routine Cardiac CT. This study compares a novel method of detecting and quantifying intracardiac shunts from the test bolus sequence of a Cardiac CT protocol, in comparison with the current non-invasive gold standard of CMR. This CT data is frequently obtained, but rarely interrogated for diagnostic purposes. The authors present a method of interrogation of this CT test bolus data to obtain an estimate of the Qp/Qs, which mirrors previous methods used with indicator dye curves. The authors report strong agreement between test bolus method, and contemporaneous CMR. [ABSTRACT FROM AUTHOR]

BackgroundTo the best of our knowledge, no study has been made until now to determine whether the ratio between pulmonary and systemic blood flow (Qp/Qs) in the pre-stage II (PS2) or pre-Glenn stage can predict the outcome in patients with hypoplastic left heart syndrome (HLHS) who underwent Norwood (NW) palliation.Patients and methodsFrom January 2016 to August 2022, 80 cardiac catheterizations in 69 patients with HLHS in NW palliation stage with modified Blalock–Taussig shunt (MBTS) were retrospectively recruited. The Qp/Qs was measured under stable conditions using the Fick formula. None of the patients were intubated. Patients were divided into two groups: Group 1 included patients who underwent planned cardiac catheterization (n = 56), and Group 2 had unplanned examination (n = 13), in which the indication for cardiac catheterization was desaturation in 11 patients and pulmonary over-circulation in two. The composite primary outcome was defined as accomplishing the planned operations (Glenn and Fontan) with freedom from death and reoperation, referring to palliative therapy or heart transplantation. The secondary outcome was freedom from transcatheter intervention in MBTS or pulmonary arteries.ResultsThe median follow-up was 48 months (range 6–72 months). The median value of Qp/Qs in Group 1 was 1.75 (range 1.5–2.2). In Group 2, the 11 patients with desaturation, the median value of Qp/Qs was 1.25 (range 0.9–1.45). The two patients with suspected pulmonary overcalculation showed Qp/Qs of 2.3 and 2.5, respectively; a reduction of the shunt size was required. Approximately 96.4% of patients in Group 1 achieved the primary outcome compared with only 30.7% in Group 2. The need for reintervention was 1.8% in Group 1 compared with 61.3% in Group 2. There is a significant relationship between Qp/Qs and the impaired outcome (death, palliative therapy, or heart transplantation) with a p-value of 0.001, a relative risk factor of 3.1, and a 95% confidence interval of 1.4–7.1. No significant relationship between the Qp/Qs and the size of MBTS (p-value of 0.073) was noted.ConclusionThe Qp/Qs in PS2 can predict outcomes in patients with HLHS in Norwood stage with MBTS. The Qp/Qs between 1.5 and 2.2 with a median of 1.75 seems to be optimal in the patients in PS2. Qp/Qs of

In order to better understand the attenuation characteristics in the crust of the central and western Tien Shan orogenic belt, we investigate both Qp and Qs values by applying the extended coda-normalization method. We estimate the frequency-dependent attenuation of both P and S waves in the frequency band of 1.0–20.0 Hz using data from local networks. The average frequency relations of Qp and Qs have been derived as Qp = (61 ± 9) × f(1.21±0.08) and Qs = (77 ± 6) × f(1.11±0.04) by fitting a power-law frequency dependence model for the study region. The low Q0 and high η values indicate that the central and western Tien Shan is a tectonically and seismically active region. We also find lateral variations of both Qp,s and Qs/Qp values, reflecting complex tectonic structures in the study area. In general, the relatively high-attenuation areas corresponding to tectonically active regions are found beneath mountainous ranges in the central Tien Shan whereas the relatively low-attenuation areas are associated with stable regions, such as Fergana Basin and Issyk-Kul Lake. Besides, regions in the central Tien Shan with Qs/Qp > 1 are likely partially saturated with fluids or rich in scattering heterogeneities, whereas regions in the western Tien Shan display Qs/Qp < 1, possibly suggesting almost complete fluid saturation. [ABSTRACT FROM AUTHOR]

Oxygen therapy is essential for the survival of preterm babies and critically ill newborns; however, it has the potential to cause harm through hypoxemia or hyperoxemia. Newborns with complex congenital heart diseases (CHD) suffer from oxygen fluctuations due to the disease and its treatments, altering pre and postnatal development. The objective of this study is to evaluate the evidence for using a hypoxic mixture to decrease pulmonary over-circulation and improve systemic perfusion before surgical interventions in newborns with complex CHD that course with pulmonary over-circulation and systemic hypoperfusion. A search was conducted in PubMed, EMBASE, LILACS, Scielo, Taylor and Francis, SAGE, and Science Direct databases from 2000 to 2022 by two independent authors, including articles with hypoxic mixture treatment in observational studies or trials, with pre-treatment and post-treatment measurements in the same patient, or two groups or more comparisons. Six articles were selected, with a total of 75 patients. The primary outcome was improved systemic circulation and decreased pulmonary over-circulation measured directly with Qp/Qs and indirectly with oxygen saturation and cerebral near-infrared spectroscopy (NIRS). In addition, we performed a meta-analysis for oxygen saturation and cerebral NIRS. Oxygen saturation was the value uniformly reported; three studies reported a significantly lower oxygen saturation after the hypoxic mixture. The cerebral NIRS was measured in 4 studies, with inconsistent results. After using the hypoxic mixture, the Qp/Qs calculation was lower in the two studies but was not statistically significant. The meta-analysis for oxygen saturation showed a fixed effect post-hypoxic therapy of -0.7 (-1.06; -0.35), p < 0.001. The meta-analysis of two studies that measured cerebral NIRS did not show a statistically significant difference at 12 and 24 hours. In conclusion, this is the first systematic review and meta-analysis regarding the pre-operative use of hypoxic gas mixtures for newborns with complex congenital heart disease. Treatment results in lower oxygen saturations, but there is a lack of evidence of improvement in systemic perfusion. The utilization of this therapy is controversial, and better evidence is necessary., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Theurel Martín et al.)

Se realizó un estudio de atenuación de ondas sísmicas en la región del volcán Puracé (VP), Colombia, mediante el cálculo del inverso del parámetro coda Q para sismos volcano-tectónicos registrados en el período 2006-2015. Para el cálculo de coda Q fueron seleccionados 310 sismos con localizaciones de alta calidad. Los resultados mostraron que los valores de Q en la zona del VP son, en general, bajos, lo que indica alta atenuación en dicha región. Adicionalmente, se relacionaron los datos de atenuación (Q-1) con valores de Vp/Vs para determinar la relación Qp −1/Qs −1. Se encontraron valores bajos en la relación Qp −1/Qs −1, los cuales pueden estar asociados a la presencia de fluidos en fase líquida y, en menor proporción, a fluidos en estado gaseoso en la parte superficial del volcán, que afectan el sistema hidrotermal y que pueden ser fuentes generadoras de la sismicidad asociada a la actividad de fluidos (sismo tipo “tornillo”, TO, y largo período, LP). Se sugiere que la actividad actual del VP está controlada por el sistema hidrotermal, con poca influencia del sistema magmático. El parámetro Qp −1/Qs −1 puede ser usado como indicador de aumento o disminución del contenido de gas en el sistema hidrotermal del volcán, lo que lo convierte en una herramienta útil para el monitoreo rutinario del VP.

Objectives A mathematical model of the oxygen delivery kinetics of the bidirectional Glenn (BDG) shunt circulation incorporating aortopulmonary collateral (APC) flow was created. The model was used to characterize oxygen delivery and compare modeled data to actual patient data obtained using cardiac magnetic resonance imaging (MRI) and catheterization. In addition, cardiac MRI and catheterization assessment of pulmonary blood flow in the presence of APC flow were compared. Design Mathematical model and retrospective data analysis of patients who underwent cardiac MRI and catheterization. The mathematical model is based on the concept that APC flow to the lungs is recirculated pulmonary venous blood flow, which does not contribute to systemic oxygen delivery. Setting Single-center, university teaching hospital. Participants The study included 98 patients with BDG shunt undergoing cardiac MRI and cardiac catheterization. Measurements and Main Results In the absence of APC flow, the pulmonary blood flow to systemic blood flow ratio (Qp/Qs) calculated using cardiac catheterization data closely matched that obtained with cardiac MRI. In the presence of APC flow, Qp/Qs calculated using cardiac catheterization data systematically underestimated values obtained with cardiac MRI. A mathematical model of BDG shunt oxygen delivery incorporating variable APC flow was created. The model provided reasonable prediction of actual patient data for arterial blood oxygen, superior vena cava oxygen saturation, and oxygen delivery obtained at the time of cardiac catheterization in patients. Conclusion The oxygen delivery kinetics of a BDG shunt incorporating variable APC flow can be modeled mathematically. Model output can be used to predict blood oxygen saturation after coil embolization of APC flow in the cardiac catheterization laboratory. [ABSTRACT FROM AUTHOR]

The indications for ductus arteriosus ligation in very-low-birth-weight infants (VLBWIs) with persistent ductus arteriosus (PDA) are unclear. Increased left ventricular end-diastolic dimension (LVDd) is commonly found in patients with PDA. Here, the enlargement of LVDd in term and preterm neonates without congenital heart disease was estimated by two-dimensional echocardiography. Methods: The value of the measured LVDd was divided by the normal LVDd as an index (LVDd ratio) to compare 30 patients who underwent PDA ligation with 30 patients treated with indomethacin and 30 patients who did not undergo radical therapy. Results: An LVDd ratio between 122% and 197% (mean, 142%) was considered to be an indication for the ligation procedure. The proportion of patients exceeding 130% in the LVDd ratio was 87% (26/30) in those patients who underwent ligation. Catecholamines and/or vasodilators were required in 83% patients for the treatment of low ejection fraction or hypertension after operations, suggesting that patients had been in preload and/or afterload remodeling failure during the operation. The percentage of patients with less than 115% in the LVDd ratio was 90% in the non-radical-therapy patients. The LVDd ratios of 130% and 115% were regarded as cut-off values for surgical ligation and indomethacin treatment. Conclusion: The LVDd ratio is a useful measure to determine the treatment of VLBWIs with PDA.

Background Optimizing systemic oxygen delivery ( DO2) and hemodynamics in children with hypoplastic left heart syndrome ( HLHS) is a clinical challenge. Mathematical modeling of the HLHS circulation has been used to determine the relationship between oxygen kinetic parameters and DO2 and to determine how DO2 might be optimized. The model demonstrates that neither arterial oxygen saturation (SaO2) nor mixed venous oxygen saturation (SvO2) alone accurately predicts DO2. Objectives Oxygen delivery kinetics predicted by previously described mathematical modeling were compared with actual patients' hemodynamic data. We sought to determine which patient derived parameters correlated best with DO2. Methods Patients with HLHS who underwent cardiac catheterization prior to surgery to create a superior cavopulmonary anastomosis from 2007 to 2011 were identified. Hemodynamic data obtained were compared with the data derived from the mathematical model. Correlations between SaO2, SvO2, SaO2-SvO2, SaO2/(SaO2-SvO2), pulmonary-to-systemic blood flow ratio ( Qp/ Qs), and DO2 were evaluated using both linear and nonlinear analyses, and R2 was calculated. Results/Conclusions Patients' data fit most aspects of the mathematical model. DO2 had the best correlation with SaO2/(SaO2-SvO2; R2 = 0.8755) followed by SaO2-SvO2 ( R2 = 0.8063), while SaO2 or SvO2 alone did not demonstrate a significant correlation as predicated by the mathematical model ( R2 = 0.09564 and 0.4831, respectively). SaO2/(SaO2-SvO2) would be useful clinically to track changes in DO2 that occur with changes in patient condition or with interventions. [ABSTRACT FROM AUTHOR]

Background: The indication for surgical repair of atrial septal defect (ASD) is pulmonary to systemic blood flow ratio (Qp/Qs) > 2.0, and therapeutic strategy depends on the facility in cases of Qp/Qs 1.5-2.0. Defect size increases with age, but hemodynamic changes of medium-sized ASD (Qp/Qs 1.5-2.0) are unknown. Methods and results: From April 1, 1985 to March 31, 2008, we experienced 125 cases of cardiac catheterization for ASD. Twelve cases were re-evaluated without surgical repair. The first and second catheterizations were performed at median ages of 7 years (range, 2-13 years) and 16 years (range, 5-19 years), respectively. The mean follow-up period was 7 years. Qp/Qs increased from 1.6 to 2.0 during follow-up (p < 0.05). Of four cases with Qp/Qs < 1.5 at initial presentation, three had Qp/Qs ≥ 1.5 at second inspection. Right ventricle diastolic volume (RVEDV/LVEDV) also increased. Conclusions: Qp/Qs and RVEDV/LVEDV of medium-sized ASD increase together in childhood. Reevaluation before adulthood should be considered in patients with no indications of ASD closure in childhood. [ABSTRACT FROM AUTHOR]

Purpose: Phase-contrast Cardiovascular Magnetic Resonance Imaging (CMR) generally requires the analysis of stationary tissue adjacent to a blood vessel to serve as a baseline reference for zero velocity. However, for the heart and great vessels, there is often no stationary tissue immediately adjacent to the vessel. Consequently, uncorrected velocity offsets may introduce substantial errors in flow quantification. The purpose of this study was to assess the magnitude of these flow errors and to validate a clinically applicable method for their correction. Materials and Methods: In 10 normal volunteers, phase-contrast CMR was used to quantify blood flow in the main pulmonary artery (Qp) and the aorta (Qs). Following image acquisition, phase contrast CMR was performed on a stationary phantom using identical acquisition parameters so as to provide a baseline reference for zero velocity. Aortic and pulmonary blood flow was then corrected using the offset values from the phantom. Results: The mean difference between pulmonary and aortic flow was 26 ± 21 mL before correction and 7.1 ± 6.6 mL after correction (p = 0.002). The measured Qp/Qs was 1.25 ± 0.20 before correction and 1.05 ± 0.07 after correction (p = 0.001). Conclusion: Phase-contrast CMR can have substantial errors in great vessel flow quantification if there is no correction for velocity offset errors. The proposed method of correction is clinically applicable and provides a more accurate measurement of blood flow. [ABSTRACT FROM AUTHOR]

: ObjectivesThis study sought to analyze the safety, efficacy, and follow-up results of percutaneous closure of secundum atrial septal defect (ASD) in young children.: BackgroundResults of ASD transcatheter closure in adults are widely reported but there are no large published series concerning young children.: MethodsBetween December 1996 and February 2002, 48 of 553 patients percutaneously treated at our institution were children age ≤5 years. Indications for closure were: elective closure in 32 patients; frequent respiratory infections in 8; failure to thrive in 2; liver transplantation in 5; and a fenestrated Fontan in 1. The procedure was carried out under general anesthesia with fluoroscopy and transesophageal control. Two different devices were used: 1) the CardioSEAL/StarFLEX (CS/SF) and 2) the Amplatzer septal occluder (ASO). Basal physical examinations and echocardiograms were performed prior to the procedure and at follow-ups (1, 6, and 12 months, and yearly thereafter).: ResultsThe mean age at closure was 3.6 ± 1.3 years. A CS/SF was used in 10 subjects; an ASO was used in 38 patients. No deaths or immediate major complications occurred. The total occlusion rate was 87% at procedure, rising to 94% at discharge. The mean follow-up was 18 ± 14 months. No midterm major or minor complications occurred. The occlusion rate rose to 100% at 12 months of follow-up. Symptomatic patients improved significantly.: ConclusionsIn the current era and in experienced hands, ASD closure can be performed safely and successfully, even in very young children. [Copyright &y& Elsevier]

: ObjectivesThe purpose of the study was to assess the long-term outcome of patients with small ventricular septal defects (VSDs) considered not to require surgical closure during childhood.: BackgroundAlthough patients with small VSDs have generally been considered not to require surgery, more recent data suggest that a significant percentage of these patients develop serious problems during adult life.: MethodsA total of 229 consecutive patients (115 females) with a VSD considered too small to require surgery during childhood as defined by normal pulmonary artery pressure, less than 50% shunt, pulmonary vascular resistance ≤200 dynes·s·cm−5, no VSD-related aortic regurgitation (AR), and no symptoms and who had no additional hemodynamically relevant heart defect were followed in an adult congenital heart disease program. Physical examination, electrocardiography, and echocardiography were performed in all patients in one- to three-year intervals; exercise tests and Holter monitoring were performed in 140 and 127 patients, respectively.: ResultsFollow-up was completed in 222 patients (97%). Mean age at last visit was 30 ± 10 years. Spontaneous VSD closure was observed in 14 patients (6%). No patients died, four patients (1.8%) had an episode of endocarditis, of whom two required aortic valve replacement, and one additional patient (0.4%) had surgical closure for hemodynamic reasons. For 118 patients who entered the study between 1993 and 1996 and were prospectively followed for 7.4 ± 1.2 years, event-free survival with end points defined as death, endocarditis or heart surgery was 99.1 ± 0.8% at three years, 96.5 ± 1.7% at six years and 95.5 ± 1.9% at eight years. At last visit, 94.6% of all patients studied were symptom free. Left ventricular (LV) size by echocardiography was normal in 198 (89%) patients, borderline in 23 patients and definitely enlarged in only one patient. None had systolic LV dysfunction, and pulmonary artery pressure (PAP) was normal in all patients. Mean exercise capacity was 92 ± 21% of expected, and 87% of patients had no arrhythmias on Holter monitoring, with the remainder showing benign rhythm disorders.: ConclusionsOutcome in well-selected patients with a small VSD is good. Surgical closure does not appear to be required during childhood as long as left-to-right shunt is <50% and signs of LV volume overload are absent, when PAP is not elevated, and no VSD-related AR or symptoms are present. [Copyright &y& Elsevier]

Objectives: A mathematical model of the oxygen delivery kinetics of the bidirectional Glenn (BDG) shunt circulation incorporating aortopulmonary collateral (APC) flow was created. The model was used to characterize oxygen delivery and compare modeled data to actual patient data obtained using cardiac magnetic resonance imaging (MRI) and catheterization. In addition, cardiac MRI and catheterization assessment of pulmonary blood flow in the presence of APC flow were compared., Design: Mathematical model and retrospective data analysis of patients who underwent cardiac MRI and catheterization. The mathematical model is based on the concept that APC flow to the lungs is recirculated pulmonary venous blood flow, which does not contribute to systemic oxygen delivery., Setting: Single-center, university teaching hospital., Participants: The study included 98 patients with BDG shunt undergoing cardiac MRI and cardiac catheterization., Measurements and Main Results: In the absence of APC flow, the pulmonary blood flow to systemic blood flow ratio (Qp/Qs) calculated using cardiac catheterization data closely matched that obtained with cardiac MRI. In the presence of APC flow, Qp/Qs calculated using cardiac catheterization data systematically underestimated values obtained with cardiac MRI. A mathematical model of BDG shunt oxygen delivery incorporating variable APC flow was created. The model provided reasonable prediction of actual patient data for arterial blood oxygen, superior vena cava oxygen saturation, and oxygen delivery obtained at the time of cardiac catheterization in patients., Conclusion: The oxygen delivery kinetics of a BDG shunt incorporating variable APC flow can be modeled mathematically. Model output can be used to predict blood oxygen saturation after coil embolization of APC flow in the cardiac catheterization laboratory., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Pulmonary hypertension associated with congenital heart disease increases the risk of surgery using cardiopulmonary bypass. Sivelestat is a neutrophil elastase inhibitor thought to have a prophylactic effect against lung injury after surgery using bypass. We elucidated that Sivelestat had the protective effect on lung in patients with congenital heart disease and pulmonary hypertension who underwent surgery using bypass., Methods: This study was a controlled prospective randomized trial and enrolled 13 neonates or infants with ventricular septal defect and pulmonary hypertension. The patients were assigned to either sivelestat with the dose of 0.2 mg/kg per hour (sivelestat group, n = 7) or saline (placebo group, n = 6) from the start of bypass until 6 hours after bypass. Proinflammatory cytokines and adhesion molecules on leukocytes were measured at 10 time points during the above period. Pulmonary function was assessed perioperatively., Results: Compared with the placebo group, the sivelestat group had significantly lower values of alveolar-arterial oxygen tension gradient at 24 hours (p = 0.038) and at 48 hours (p = 0.028) after bypass, and significantly better balance of hydration at 48 hours after bypass (p = 0.012). The sivelestat group also showed significantly lower plasma levels of interleukin-8 immediately after bypass (p = 0.041) and interleukin-10 at 15 minutes after removal of the aortic cross-clamp (p = 0.048), and immediately after bypass (p = 0.037)., Conclusions: Administration of sivelestat during bypass prevented pulmonary damage and activities of proinflammatory cytokines at the cardiac operation in neonates or infants. Our results show that sivelestat may be considered to protect pulmonary function against the injury by bypass., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)