Morphometric Analysis of the Aorto-Esophageal Relationship in Swine for Trans-Esophageal Aortic Blood Flow Occlusion

Background Trans-esophageal aortic blood flow occlusion (TEABO) is an emerging technology undergoing laboratory research that offers a strategy for temporary hemorrhage control. The purpose of this study was to evaluate the anatomical relationship between the esophagus and descending thoracic aorta in two breeds of swine to support a porcine model for future TEABO investigations. Methods Thoracoabdominal CT scans were compared in Hanford miniature swine and Yorkshire swine. Measurements were taken at the five vertebral levels proximal to the gastroesophageal junction. Data collected included the distance between the center of the esophagus and the center of the descending aorta, the angle between the vertebral column, descending aorta, and esophagus, and the length the thoracic esophagus travels anteriorly to the descending aorta. Results Ten Hanford swine and ten Yorkshire swine were compared. In Hanford swine, the distal thoracic esophagus travels anteriorly to the descending aorta for a mean distance of 11.5 ± 2.3 cm. In Yorkshire swine, the thoracic esophagus travels to the right of the descending aorta. The mean angle between the vertebral body, descending aorta, and esophagus was 79.6 to 97.8 degrees higher in Hanfords compared to Yorkshires (p<0.0001 at all five vertebral levels compared). The mean distance between the esophagus and descending aorta was 0.2 to 0.6 cm higher in Hanfords compared to Yorkshires with a significant difference found at only two vertebral levels (p=0.01 and p=0.02). Conclusion Hanford miniature swine possess an aorto-esophageal relationship comparable to humans and should be the preferred animal model for TEABO studies.

Peripheral vascular involvement in transthyretin cardiac amyloidosis. A comparative analysis with AL amyloidosis

Background The pattern of peripheral vascular involvement in the wild type transthyretin-related cardiac amyloidosis (ATTRwt) and its diagnostic utility in differentiating this infiltrating cardiomyopathy from light chain (AL) cardiac amyloidosis (AL-CA) and heart failure with preserved ejection fraction (HFpEF) of different origin have not been explored. Aims To characterize the pattern of peripheral vascular involvement in ATTRwt and evaluate its value in differentiating ATTRwt from AL-CA and HFpEF. Methods Newly diagnosed patients with ATTRwt (n=42) were consecutively recruited from our amyloidosis center. These patients were matched 1:1 for age and sex to patients with AL-CA (n=32) and subjects without amyloidosis (n=32) and also matched 2:1 to HFpEF patients (n=16). All subjects underwent a series of non-invasive vascular examinations for the assessment of: 1. subclinical carotid atherosclerosis with B-mode ultrasonography, 2. Arterial stiffness with measurement of carotid-femoral pulse wave velocity, 3. Reactive vasodilation with flow-mediated dilation (FMD) and 4. Aortic blood pressures and arterial wave reflections with augmentation index (AI) and return time of reflected wave (Tr). Results ATTRwt patients had lower peripheral (pBP) and aortic blood pressure (aBP) markers compared to non-AL controls (p&lt;0.05 for all). ATTRwt grouping was an independent determinant of these markers, after adjustment for cardiovascular risk factors (CVRF), including history of hypertension, hyperlipidemia and diabetes, glomerular filtration rate, body mass index and smoking status (core model). ATTRwt had lower aDBP and increased Tr compared to AL subjects. In a comparison between ATTRwt and AL patients with cardiac involvement, AI and Tr were higher and FMD lower in ATTRwt patients. ATTRwt was an independent determinant of these markers, after adjustment for the core model (p&lt;0.05 for all). Compared to HFpEF, patients with ATTRwt had lower peripheral and central BP and higher Tr (p&lt;0.05 for all). By ROC analysis, Tr provided high diagnostic value for ATTRwt vs. AL-CA (Area Under the Curve, AUC=0.809, CI: 0.65–0.96) and for ATTRwt vs combined AL-CA and HFpEF (AUC=0.880, CI: 0.79–0.97). Finally, AI was closely correlated with posterior (Spearman's Rho=−0.30) and intraventricular wall thickness (Rho=−0.329) and left ventricular global longitudinal strain (Rho=−0.4) and lower cDBP with higher Gilmore and New York Heart Association stage (p&lt;0.05). Conclusion ATTRwt patients present differential characteristics of peripheral vascular function and aortic hemodynamics as compared to AL, HFpEF and healthy controls. The clinical value of these characteristics merit further investigation since differential diagnosis among amyloidosis types is clinically challenging, while it may have prognostic implications. FUNDunding Acknowledgement Type of funding sources: None.

The predictive value of central aortic blood pressure on new onset stroke and differences between brachial blood pressure in a Chinese hypertensive population, a prospective cohort study

Objectives This study aimed to investigate the association between noninvasive central aortic blood pressure and the risk of first stroke in a Chinese community–based population, meanwhile compare the prediction ability of central SBP and peripheral SBP. Methods A total of 8473 Chinese participants without history of stroke and atrial fibrillation at baseline were selected from “Hypertension and Stroke Prevention and Control Project” for analysis. The endpoint of the study was first total stroke and stroke subtypes (ischemic stroke and hemorrhagic stroke). Cox proportional hazards regression, smoothing curve fitting, subgroup analysis, and Kaplan-Meier curve were used to analysis the relationship between central/peripheral systolic blood pressure and first stroke. Results Participants were 60.9±9.6 years old, 63.5% were males, and 96.1% had hypertension. After a mean 3.3-year follow-up, the incidence of first total stroke, first ischemic stroke and first hemorrhagic stroke were 5.1%, 4.6%, and 0.5%, respectively. In multivariate logistic-regression analyses, central and peripheral SBP were both independently associated with first total stroke and first ischemic stroke after adjusting for various confounders. Peripheral SBP's significant association with first total and ischemic stroke disappeared when combined analyzed with central SBP, whereas central SBP was still significantly related with first total and ischemic stroke after adjustment of peripheral SBP. For first hemorrhagic stroke, no significant differences were observed between central SBP and peripheral SBP. Subgroup analysis showed that the central SBP-first stroke association was significantly stronger in males (HR: 1.38; 95% CI: 1.16, 1.63) than in females (HR: 1.10; 95% CI: 0.97, 1.24; P-interaction = 0.028). Conclusions Among the Chinese community–based population, central SBP is a stronger predictor compared with peripheral SBP for first stroke, especially ischemic stroke. FUNDunding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Key R&D Projects, JiangxiOutstanding Person Foundation

End-organ saturations correlate with aortic blood flow estimates by echocardiography in the extremely premature newborn – an observational cohort study

Background Near-infrared spectroscopy (NIRS) measures of cerebral saturation (Csat) and renal saturation (Rsat) in extreme premature newborns may be affected by systemic blood flow fluctuations. Despite increasing clinical use of NIRS to monitor tissue saturation in the premature infant, validation of NIRS measures as a correlate of blood flow is still needed. We compared echocardiography (ECHO) derived markers of ascending aorta (AscAo) and descending aorta (DesAo) blood flow with NIRS measurements obtained during the ECHO. Methods Newborns < 29 weeks’ gestation (2013–2017) underwent routine NIRS monitoring. Csat, Rsat and systemic saturation at the time of ECHO were retrospectively analyzed and compared with Doppler markers of aortic flow. Renal and cerebral fractional tissue oxygen extraction (rFTOE and cFTOE, respectively) were calculated. Mixed effects models evaluated the association between NIRS and Doppler markers. Results Forty-nine neonates with 75 Csat-ECHO and 62 Rsat-ECHO observations were studied. Mean post-menstrual age was 28.3 ± 3.8 weeks during the ECHO. Preductal measures including AscAo velocity time integral (VTI) and AscAo output were correlated with Csat or cFTOE, while postductal measures including DesAo VTI, DesAo peak systolic velocity, and estimated DesAo output were more closely correlated with Rsat or rFTOE. Conclusions NIRS measures are associated with aortic blood flow measurements by ECHO in the extremely premature population. NIRS is a tool to consider when following end organ perfusion in the preterm infant.