Angiographic velocimetry analysis using contrast dilution gradient method with a 1000 frames per second photon-counting detector

Purpose

Contrast dilution gradient (CDG) analysis is a quantitative method allowing blood velocity estimation using angiographic acquisitions. Currently, CDG is restricted to peripheral vasculature due to the suboptimal temporal resolution of current imaging systems. We investigate extension of CDG methods to the flow conditions of proximal vasculature using 1000 frames per second (fps) high-speed angiographic (HSA) imaging.

Approach

We performed in-vitro HSA acquisitions using the XC-Actaeon detector and 3D-printed patient-specific phantoms. The CDG approach was used for blood velocity estimation expressed as the ratio of temporal and spatial contrast gradients. The gradients were extracted from 2D contrast intensity maps synthesized by plotting intensity profiles along the arterial centerline at each frame. In-vitro results obtained at various frame rates via temporal binning of 1000 fps data were retrospectively compared to computational fluid dynamics (CFD) velocimetry. Full-vessel velocity distributions were estimated at 1000 fps via parallel line expansion of the arterial centerline analysis.

Results

Using HSA, the CDG method displayed agreement with CFD at or above 250 fps [mean-absolute error (MAE): 2.6±6.3  cm/s, p=0.05]. Relative velocity distributions correlated well with CFD at 1000 fps with universal underapproximation due to effects of pulsatile contrast injection (MAE: 4.3 cm/s).

Conclusions

Using 1000 fps HSA, CDG-based extraction of velocities across large arteries is possible. The method is sensitive to noise; however, image processing techniques and a contrast injection, which adequately fills the vessel assist algorithm accuracy. The CDG method provides high resolution quantitative information for rapidly transient flow patterns observed in arterial circulation.

Independent predictors of long-COVID in patients without comorbidities. Data from the Polish long-COVID cardiovascular (PoLoCOV-CVD) study

 

Coronavirus disease 2019 (COVID-19) is a serious respiratory disease that results from infection with a newly discovered coronavirus (SARS-COV-2). Patients recovering from SARS-COV2 infection complain of persisting symptoms which may lead to chronic fatigue syndrome and as well as many other complications. The vast majority of COVID-19 patients remaining in isolation/quarantine, due to the mild course of the disease, do not require hospitalization. There are many studies describing the course and complications of patients hospitalized due to COVID-19. There is little published data on how nonhospitalized patients get sick and what are the early and late complications of SARS-CoV-2 infection. Little is also known about Long-COVID (LC) in patients without comorbidities. Therefore, the aim of our analysis was to assess the predictors of long-lasting symptoms in patients without comorbidities suffering from COVID-19.

Methods

Patients ≥18 years of age diagnosed with COVID-19, were examined after full recovery (resolution of clinical symptoms, minimum 14 days after last symptoms). Patient information, course of the disease with symptoms, post-COVID-19 complaints were collected within 4–8 weeks after the COVID-19 recovery. We followed patients for at least 3 months. Patients were ordered the following tests: 12-lead ECG, 24-hour Holter ECG monitoring, 24-hour Holter blood pressure monitoring, Echocardiographic of the Heart assessment, Biochemical tests: lipid profile, glucose or glycosylated hemoglobin level, D-dimers. In patients with indications, the following were additionally performed: Magnetic resonance imaging of the heart, Computed tomography angiography (CTA) of pulmonary vessels, Angio CT of coronary vessels or other diagnostic tests.

Results

We identified 701 consecutive patients without comorbidities of whom 488 pts completed 3 month follow-up. Comparisons were made between LC group (n=218) and non-LC group (n=270). The demographic and laboratory characteristics of the studied group are presented in Table 1. Patients with severe course of acute phase of COVID-19 developed LC more often (72 vs. 28%, p<0.001). Significant differences regarding sex, weight, height, body mass index were observed. Patients with LC more often presented with dyspnoea, significant fatigue, chest pain, leg muscle pain, headache, arthralgia and chills. No statistically significant difference was observed regarding laboratory tests, 24-hour systolic and diastolic BP and echocardiographic parameters. LC group had higher 24-hour heart rate (77 [72–83] vs. 75 [70–81], p=0.021). Multivariate regression analysis showed that LC patients had higher BMI (odds ratio 1.057, 95% confidence intervals 1.016–1.100) and almost twice as often had a severe course (1.736, 1.071–2.814) and presented with arthralgia in the acute phase (1.901, 1.225–2.950).

Conclusions

Severe course of COVID-19, BMI, and arthralgia are independently related to long-COVID in patients without comorbidities.

Funding Acknowledgement

Type of funding sources: None.

Anxiety and depression among ambulatory and hospitalized patients with cardiovascular long-COVID-19 presentation referred to cardiology consultation after COVID-19 infection

Introduction

COVID-19 is connected with varying degrees of emotional stress. Patients (pts) who are hospitalized with severe COVID-19 (C19) are located in single rooms without a permanent attendant to prevent contamination. All personnel serving these pts come into contact with patients with personal full-body protective garment. Ambulatory C19 pts, usually with less severe presentation, are treated in more comfortable conditions.

Purpose

To evaluate the impact of the psychosocial changing conditions on individuals' psyche and to analyse the differences in terms of experienced anxiety and depression among the ambulatory and hospital patients referred to post-C19 cardiology consultation.

Methods

The study involved 388 pts with persistent cardiovascular symptoms, including 198 ambulatory patients (130 females and 68 males) and 190 hospital patients (128 females and 62 males) referred to the cardiology consultation (mean age 4.9±12.9 and 50.5±14.4 years, respectively). The data were collected using the specially designed questionnaire related to descriptive characteristics of the patients and to standardized questionnaires: the State-Trait Anxiety Inventory (STAI) and Beck's Depression Inventory (BDI).

Results

Abnormal psychological metrics was common in the study pts. Indicators of anxiety were lower in the ambulatory than in hospitalized pts (p<0.001). Depression level was also lower in the ambulatory pts (p<0.001). The same differences were statistically significant in both female and male pts subsets. However, anxiety and depression were more pronounced among female than male pts. Very strong positive correlation was observed between anxiety - state and depression among ambulatory patients, both females and males (p<0.05).

Conclusions

C19 convalescents with persistent symptoms of presumed cardiovascular origin present with abnormal psychological traits including increased anxiety and depression especially in individuals requiring hospital treatment. For this reason, it is necessary to plan the interventions particularly in hospitalized pts to reduce their anxiety and depression levels and to create psychological support programs.

Funding Acknowledgement

Type of funding sources: None.

Predictors and clinical consequences of heart damage in CMR in patients after COVID-19

Methods

Out-hospital clinic patients (pts) recovered from COVID-19 were prospectively recruited and underwent cardiac magnetic resonance (CMR) examination with a protocol including: edema, hyperemia, and necrosis or scar-derived from signal intensity assessment in T2-weighted, early gadolinium enhancement (EGE) and late gadolinium enhancement (LGE) CMR images.

Results

A total of 702 patients (mean age 50±12 years, 62% female) were included. The median (IQR) time interval between COVID-19 diagnosis and CMR was 13 (8–22) weeks. In none pts signs of edema, hyperemia and necrosis derived from signal intensity assessment in T2-weighted and early gadolinium enhancement was found. LGE was found in 152 (22%). LGE+ patients had significantly lower left ventricular (LV) ejection fraction (58.5±7.7 vs 61.1±7.9%, p&lt;0.001) and greater LV end-diastolic (117.0±52.2 vs 103,0±36.3 ml, p=0.023) and end-systolic (50.3±28.0 vs 41.0±17.5 ml, p=0.010) volumes when compared with LGE− patients. In the resting electrocardiogram (ECG) fragmented QRS was observed significantly more frequently (46% vs 25%, p&lt;0.001) in LGE+ group, whereas in 24h Holter ECG neither single premature, nor complex ventricular extrasystole burden did not differ between groups (p&gt;0.05). There were observed no differences between symptoms of COVD-19 and comorbidities between LGE+ and LGE− pts. In the multivariable logistic regression analysis: fragmented QRS [OR and 95% CI: 2.85 (1.93–4.21)] and any ST-T segment deviation in resting ECG [OR: 1.93 (1.15–3.25)] were identified as independent predictors of LGE, even after adjustment for comorbidities and COVID-19 symptoms.

Conclusions

1. In patients with fibrosis after COVID-19 reduced left ventricular ejection fraction and greater volume of the heart was found.

2. Fragmented QRS and ST-T abnormalities were independent predictors for LGE in patients after COVID-19.

Funding Acknowledgement

Type of funding sources: None.

Semi-automatic Co-Registration of 3D CFD Vascular Geometry to 1000 FPS High-Speed Angiographic (HSA) Projection Images for Flow Determination Comparisons

Image co-registration is an important tool that is commonly used to quantitatively or qualitatively compare information from images or data sets that vary in time, origin, etc. This research proposes a method for the semi-automatic co-registration of the 3D vascular geometry of an intracranial aneurysm to novel high-speed angiographic (HSA) 1000 fps projection images. Using the software Tecplot 360, 3D velocimetry data generated from computational fluid dynamics (CFD) for patient-specific vasculature models can be extracted and uploaded into Python. Dilation, translation, and angular rotation of the 3D velocimetry data can then be performed in order to co-register its geometry to corresponding 2D HSA projection images of the 3D printed vascular model. Once the 3D CFD velocimetry data is geometrically aligned, a 2D velocimetry plot can be generated and the Sørensen-Dice coefficient can be calculated in order to determine the success of the co-registration process. The co-registration process was performed ten times for two different vascular models and had an average Sørensen-Dice coefficient of 0.84 ± 0.02. The method presented in this research allows for a direct comparison between 3D CFD velocimetry data and in-vitro 2D velocimetry methods. From the 3D CFD, we can compare various flow characteristics in addition to velocimetry data with HSA-derived flow metrics. The method is robust to other vascular geometries as well.

What can we find in the ECG recording in convalescent from COVID-19 with mild and moderate course

Funding Acknowledgements

Methods

Results

The Cardiac Safety of Chloroquine Phosphate Treatment in Patients with Systemic Lupus Erythematosus: The Influence on Arrhythmia, Heart Rate Variability and Repolarization Parameters

Antimalarials are used to treat cutaneous and systemic lupus erythematosus (SLE). Even though cardiac damage is a rare complication, over the last decade several reports have raised the issue of cardiotoxicity associated with antimalarials. Therefore, the aim of study was to evaluate the influence of seven-month chloroquine treatment with a 250 mg daily dose on arrhythmia, conduction disturbances as well as heart rate variability and repolarization parameters assessed in 24-hour Holter monitoring. The studied group included 28 SLE patients treated with chloroquine as a monotherapy. In all the patients standard 12 leads surface ECG (50 mm) and the 24-hour ECG Holter monitoring (Oxford Medilog Excel-2) were performed before and after chloroquine phosphate treatment. All subjects presented sinus rhythm both at the enrollment and after treatment. No episodes of paroxysmal arrhythmias or conduction disturbances were reported during the study. All the patients were characterized by tendency to tachycardia, but no significant differences in mean heart rate were found before and after chloroquine administration. Similarly, no changes in heart rate variability or repolarization parameters were observed.

Alteration of human serum albumin tertiary structure induced by glycation. Spectroscopic study

The modification of human serum albumin (HSA) structure by non-enzymatic glycation is one of the underlying factors that contribute to the development of complications of diabetes and neurodegenerative diseases. The aim of the present work was to estimate how glycation of HSA altered its tertiary structure. Changes of albumin conformation were investigated by comparison of glycated (gHSA) and non-glycated human serum albumin (HSA) absorption spectra, red edge excitation shift (REES) and synchronous spectra. Effect of glycation on human serum albumin tertiary structure was also investigated by (1)H NMR spectroscopy. Formation of gHSA Advanced Glycation End-products (AGEs) caused absorption of UV-VIS light between 310 nm and 400 nm while for non-glycated HSA in this region no absorbance has been registered. Analysis of red edge excitation shift effect allowed for observation of structural changes of gHSA in the hydrophobic pocket containing the tryptophanyl residue. Moreover changes in the microenvironment of tryptophanyl and tyrosyl residues brought about AGEs on the basis of synchronous fluorescence spectroscopy have been confirmed. The influence of glycation process on serum albumin binding to 5-dimethylaminonaphthalene-1-sulfonamide (DNSA), 2-(p-toluidino) naphthalene-6-sulfonic acid (TNS), has been studied. Fluorescence analysis showed that environment of both binding site I and II is modified by galactose glycation.

Effects of non-enzymatic glycation in human serum albumin. Spectroscopic analysis

Human serum albumin (HSA), transporting protein, is exposed during its life to numerous factors that cause its functions become impaired. One of the basic factors --glycation of HSA--occurs in diabetes and may affect HSA-drug binding. Accumulation of advanced glycation end-products (AGEs) leads to diseases e.g. diabetic and non-diabetic cardiovascular diseases, Alzheimer disease, renal disfunction and in normal aging. The aim of the present work was to estimate how non-enzymatic glycation of human serum albumin altered its tertiary structure using fluorescence technique. We compared glycated human serum albumin by glucose (gHSA(GLC)) with HSA glycated by fructose (gHSA(FRC)). We focused on presenting the differences between gHSA(FRC) and nonglycated (HSA) albumin used acrylamide (Ac), potassium iodide (KI) and 2-(p-toluidino)naphthalene-6-sulfonic acid (TNS). Changes of the microenvironment around the tryptophan residue (Trp-214) of non-glycated and glycated proteins was investigated by the red-edge excitation shift method. Effect of glycation on ligand binding was examined by the binding of phenylbutazone (PHB) and ketoprofen (KP), which a primary high affinity binding site in serum albumin is subdomain IIA and IIIA, respectively. At an excitation and an emission wavelength of λex 335nm and λem 420nm, respectively the increase of fluorescence intensity and the blue-shift of maximum fluorescence was observed. It indicates that the glycation products decreases the polarity microenvironment around the fluorophores. Analysis of red-edge excitation shift method showed that the red-shift for gHSA(FRC) is higher than for HSA. Non-enzymatic glycation also caused, that the Trp residue of gHSA(FRC) becomes less accessible for the negatively charged quencher (I(-)), KSV value is smaller for gHSA(FRC) than for HSA. TNS fluorescent measurement demonstrated the decrease of hydrophobicity in the glycated albumin. KSV constants for gHSA-PHB systems are higher than for the unmodified serum albumin, while KSV values for gHSA-KP systems are only slightly lower than that obtained for HSA-KP. The affinity of PHB to the glycated HSA is stronger than to the non-glycated in the first class binding sites within subdomain IIA, in the vicinity of Trp-214. Ketoprofen bound to unmodified human serum albumin stronger than for glycated albumin and one class of binding sites is observed (Scatchard linear plots).

Abstract P6-11-07: Quantitative p95HER2 levels in primary breast cancers and in matched brain metastases

Background: Patients with HER2-positive breast cancer are at high risk for brain metastases. A large number of HER2-positive tumors also express p95HER2 (p95), a truncated form of HER2 that lacks the trastuzumab binding site but retains kinase activity. Although p95 expression in primary breast tumors is well studied, the prevalence and significance of p95 expression in brain metastases is unknown. In the current study we examined expression of p95 in brain metastases and in matched primary breast tumors.

Methods: Seventy-five pairs of formalin-fixed paraffin-embedded samples from matched primary breast cancers and brain metastases were assayed for quantitative p95 protein expression using the p95 VeraTag® assay (Clin Cancer Res, 16:4226, 2010) specific for the M611 form of p95. Sufficient material to obtain p95 data in both primary and matched brain metastasis samples was available in 52 cases. In the remaining 23 cases, a p95 measurement was obtained in either the primary or brain metastasis sample. Estrogen (ER) and progesterone (PR) receptor status were scored using immunohistochemistry. Hormone receptor positivity was defined as either ER or PR positive. Quantitative HER2 protein expression was measured using the HERmark® assay. Both the p95 VeraTag assay and the HERmark assay measure tumor-averaged protein expression in units of relative fluorescence per mm2 tumor (RF/mm2). Measurements of p95 &gt; 2.8 RF/mm2 and HER2 &gt; 17.8 RF/mm2 were considered as positive results.

Results: There was a net increase in p95 expression in brain metastases relative to the matched primary tumor with a median increase of 1.5-fold (p = 0.001, range 0.2-fold to 35-fold). The increase in p95 expression was only weakly correlated with the increase in quantitative HER2 expression (R2 = 0.18; p = 0.0018). Cases with HERmark-positive tumors were more likely to have the largest (≥ 5-fold) increase in p95 expression compared to those with lower HER2 expression (odds ratio = 6.3; p = 0.018). Changes in p95 levels from primary to brain metastasis were unrelated to hormone receptor status (p = 0.59). P95 positivity in the primary tumor correlated with time from breast cancer diagnosis to first progression (HR = 2.2; p = 0.012) when stratified by hormone receptor status and tumor grade. Although there was a trend towards correlation of p95 positivity in the brain metastasis with time from diagnosis to brain metastasis (HR = 1.7; p = 0.058, stratified as above), p95 positivity did not correlate with overall survival from the time of brain metastasis diagnosis (HR = 1.3; p = 0.42, stratified as above).

Conclusions: This is the first study of quantitative p95 expression in matched primary tumors and brain metastases. Brain metastases of breast cancer show significant increases in p95 protein expression compared to matched primary tumors. These data provide a rationale for future correlative studies on p95 levels in brain metastases.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-11-07.