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Background: To investigate deep vein thrombosis (DVT) in hospitalized patients with coronavirus disease 2019 (COVID-19), we performed a single institutional study to evaluate its prevalence, risk factors, prognosis, and potential thromboprophylaxis strategies in a large referral and treatment center. Methods: We studied a total of 143 patients with COVID-19 from January 29, 2020 to February 29, 2020. Demographic and clinical data, laboratory data, including ultrasound scans of the lower extremities, and outcome variables were obtained, and comparisons were made between groups with and without DVT. Results: Of the 143 patients hospitalized with COVID-19 (age 63±14 years, 74 [51.7%] men), 66 patients developed lower extremity DVT (46.1%: 23 [34.8%] with proximal DVT and 43 [65.2%] with distal DVT). Compared with patients who did not have DVT, patients with DVT were older and had a lower oxygenation index, a higher rate of cardiac injury, and worse prognosis, including an increased proportion of deaths (23 [34.8%] versus 9 [11.7%]; P =0.001) and a decreased proportion of patients discharged (32 [48.5%] versus 60 [77.9%]; P P =0.031), Padua prediction score ≥4 (odds ratio, 4.016; P =0.04), D-dimer >1.0 μg/mL (odds ratio, 5.818; P 1.0 μg/mL has a sensitivity of 88.52% and a specificity of 61.43% for screening for DVT. In the subgroup of patients with a Padua prediction score ≥4 and whose ultrasound scans were performed >72 hours after admission, DVT was present in 18 (34.0%) patients in the subgroup receiving venous thromboembolism prophylaxis versus 35 (66.0%) patients in the nonprophylaxis group ( P =0.010). Conclusions: The prevalence of DVT is high and is associated with adverse outcomes in hospitalized patients with COVID-19. Prophylaxis for venous thromboembolism may be protective in patients with a Padua protection score ≥4 after admission. Our data seem to suggest that COVID-19 is probably an additional risk factor for DVT in hospitalized patients. more...

Background and Objective: The hemodynamics of fetal circulation and its alterations, as in cases of congenital heart defects (CHD), have been investigated in instrumented animal models or in human fetuses by noninvasive fetal echocardiography and Doppler (FED). There is little data in computational modeling of fetal circulation due to challenges in fetal cardiac imaging and the availability of validation methodologies. This study aims to develop and validate a computational model for assessing hemodynamics in aortic and ductal arches in human fetuses. Methods: Figure 1 shows our computational workflow. The process started by preparing a reconstructed 3D aortic and ductal arch anatomy derived from 3D FED. Then, the computational model was built and validated using clinical data from five human fetuses. The primary output was the velocity waveform at the aortic isthmus (AoI), validated using tracings from spectral Doppler. Results: Upon superimposing the reconstructed fetal aortic arch anatomies onto the original 3D FED stack, our results demonstrated a precise rendering of each subject’s unique vessel structure. Simulations were run for ten cardiac cycles, with each velocity waveform at the AoI showing a discrepancy of less than 15% when compared with the Doppler echocardiography tracings. These findings indicate a good agreement between our computational model and the FED data. Conclusion: This study presents the development and validation of a computational model for assessing patient-specific hemodynamics in the aortic arches of human fetuses. Continued investigation is warranted to further validate and apply this approach to improve the diagnosis, prognosis, and treatment of CHD in human fetuses. more...

Background: Torsion of the left ventricle is related to myocardial architecture and contractility and is being evaluated as a sensitive marker of cardiac performance. New 2-D speckle tracking imaging (STI) may provide a powerful means of assessing LV torsion noninvasively. This study sought to evaluate the global and regional left ventricular twist in patients with anterior wall myocardial infarction (AMI) before and after revascularization by STI. Methods: A total of 50 subjects, including study group (n = 20) who underwent revascularization for AMI as well as 1 month after revascularization, and control group (n = 30) of normal individuals were studied using STI. LV twist was defined as apical rotation relative to the base. The peak LV twist, standard deviation of time to peak twist (Tw-SD) and maximal temporal difference of time to peak twist (Tw-diff) of 6 myocardial regions were measured. Results: Before revascularization, peak LV twist was significantly reduced while Tw-SD and Tw-diff significantly increased in patients with AMI as compared with normal control group ( P ). There were significant correlations between LV peak twist and LVEF ( r =0.78, P r =−0.63, P Conclusion: LV twist measures significantly diminished and dys-synchronized in AMI patients prior to revascularization and improved after revascularization. STI measures correlate with EF and have the potential to quantify left ventricular global and segmental dysfunction in patients with AMI. Left ventricular regional and global peak twist, torsion and synchrony measures more...

Background : Thoracic aortic aneurysm and dissection (TAAD) is the leading cause of death in patients with Marfan syndrome (MFS) and other aortic disease (AD). The natural history of AD aries significantly. The size of the aorta alone does not always predict the risks of complications, such as catastrophic TAAD. Objectives : We sought to develop an ultrasound technique to quantitatively measure deformation of the ascending aorta (Ao) using a real-time 2-D ultrasound speckle tracking imaging (USTI) technique to investigate: alterations in biomechanical properties of AAo in MFS, and early and sensitive markers for TAAD for MFS. Methods: A total of 40 patients (MFS: n=18, age=11.4 ± 6.2 years, versus Control: n = 22, age=10.2 ± 4.3, p = 0.46) were prospectively enrolled. Real-time 2-D echocardiography was performed. The dimension of the AAo root (at the level of aortic annulus, sinus of Valsalva (SOV), sino-tubular junction and ascending aorta) was tracked and measured continuously in the cardiac cycle to derive the maximal and minimal systolic and diastolic dimensions using USTI (Philips Medical Systems). These measurements were used to yield dimensions, strain (deformation), strain rate (rate of deformation), distensibility, stiffness index and elastic modulus. Results: The results were summarized in Table 1 . Compared with controls, the MFS group had significantly enlarged dimension of the AAo root (P Conclusions: This study demonstrated the feasibility of quantitative measurement of the biomechanical properties of the AAo in MFS using USTI. We have also shown significant deterioration of the biomechanical properties in MFS. Table 1. Biomechanical properties of AAO in MFS more...

Background. Ascending thoracic aortic aneurysms leading to type A dissections (TAAD) are a life-threatening disease triggered by a complex interactions between environmental and genetic factors. Pathologically, this disease is characterized by a progressive loss of vascular smooth muscle cells (SMCs) and extracellular elastic fibers in the aortic media. Apoptosis, a form of programmed cell death, has been shown to contribute to the loss of medial SMCs. However, little is known about the role of vascular progenitor or stem cells in the pathogenesis of aortic aneurysms. Methods and Results. In this study we examined expression of Tie-2 (receptor for angiopoietin) and Flk-1 (receptor for vascular endothelial cell growth factor), two receptors critical for regulation of vascular stem cell survival and growth in the aortic lesions of patients with TAAD. Immunohistochemistry with specific antibodies against Tie-2 and Flk-1 showed a marked reduction in the numbers of Tie+/Flk+ cells in TAAD when compared to control aortas. There was also a change in the distribution pattern of vascular progenitor cells positive for both Tie-2 and Flk-1 in TAAD patients’ aortic tissues. Compared to normal control aortas, the Tie-2 and Flk-1 immunostained cells were much lower in intensity and scattered. In the regions with paucity of Tie-2+/Flk-1+ cells, there was an increased number of apoptotic cells as determined by in situ DNA end-labeling (TUNEL). Many of the Tie-2 and Flk-1 positive cells in TAAD showed poor morphology with nuclear degeneration and cytoplasmic fragmentation and disarray. Conclusion . These results indicate a paucity of Tie-2+/Flk-1+ vascular stem cells in the aortic wall of patients with TAAD, implying that the stem cell capacity to regenerate SMCs is exhausted. Similar loss of stem cells is observed with Duchenne muscular dystrophy, where the regenerated capacity is significantly compromised. Stem cells loss may similarly impair the capacity of SMCs in aortic tissue in repair and regeneration, and ultimately lead to TAAD formation. more...

A 2-month-old infant with a double-outlet right ventricle, pulmonary stenosis, a subaortic ventricular septal defect, a hypoplastic mitral valve, a hypoplastic left ventricle, and a restrictive atrial septal defect was seen at an outside institution. The initial plan was to palliate the child with an atrial septectomy, have the pulmonary artery oversewn, and perform a modified Blalock-Taussig shunt. During surgery, an anomalous origin of the left lower pulmonary artery was noted originating from the right pulmonary artery. The possibility of a left … more...

A 13-year-old girl who had complete transposition of the great arteries after Mustard repair at 2 months of age developed superior baffle obstruction. During cardiac catheterization and as a guide for balloon dilation, the obstruction was imaged by transesophageal ultrasound and angiography (Fig 1⇓). Before dilation, the mean pressure gradient was 8 mm Hg, and a small … more...