Analysis of Radiofrequency Ultrasound Signals

2011 ◽  
pp. 55-93
Author(s):  
Attila Thury ◽  
Héctor M. Garcia-Garcia ◽  
Evelyn Regar
Keyword(s):  
Coronary Atherosclerosis ◽  
Plaque Rupture ◽  
Local Treatment ◽  
Natural History Study ◽  
Strain Measurements ◽  
Preventive Cardiology ◽  
Vulnerable Plaques ◽  
One Stop ◽  
Very High ◽  
Radiofrequency Signal

IVUS opened new perspectives in our understanding of human coronary atherosclerosis and triggers of ACS (especially plaque rupture as its most dominant cause). Throughout this chapter we list the shortcomings of conventional (greyscale) IVUS to characterize tissue components of plaques and the potentials of radiofrequency signal processing to overcome these. In recent years, the technology matured, and especially with VH and IB-IVUS, many clinical studies showed accurate plaque estimation. Results of a prospective, natural history study have just been presented and proved the ability of VH to predict ACS. Palpography derives compositional information from functional (strain) measurements. Assessing several characteristics of a given plaque could potentially enhance invasive risk stratification by identifying very high-risk plaques, thereby reducing the number of vulnerable plaques that need to be serially followed and ultimately treated. Moreover, if a safe prophylactic local treatment was available, a sophisticated IVUS procedure would be a part of a “one-stop-shop” in preventive cardiology.

scholarly journals Prediction of subclinical coronary atherosclerosis in patients with high and very high cardiovascular risk

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
N Pogosova ◽  
NP Kachanova ◽  
YM Yufereva ◽  
OY Sokolova ◽  
IE Koltunov ◽  
...  
Keyword(s):  
Family History ◽  
Ct Angiography ◽  
Coronary Atherosclerosis ◽  
Subclinical Atherosclerosis ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Diagnostic Model ◽  
History Of ◽  
Hs Crp ◽  
Very High

Abstract Funding Acknowledgements Type of funding sources: None. Background Coronary atherosclerosis has a long subclinical period. It’s early detection may offer a possibility of timely initiation of preventive interventions Purpose To develop a diagnostic rule for detection of patients (pts) with high probability of subclinical atherosclerosis among those with high or very high cardiovascular (CV) risk. Methods This cross-sectional study enrolled 52 pts (32 men [62%]), aged 40 to 65 years [mean age 54.6 ± 8.0]) with high or very high CV risk (5-9 and ≥10% by The Systematic Coronary Risk Estimation Scale [SCORE], respectively). All participants underwent cardiac computed tomography (CT) angiography and calcium scoring. Traditional risk factors (RFs) (family history of premature CVD, smoking, overweight/obesity and abdominal obesity, hypertension, type 2 diabetes mellitus, lipids parameters (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides) and lipids-related markers (apolipoprotein A1, apolipoprotein B, ApoB/ApoA1 ratio), biomarkers of inflammation (high-sensitivity C-reactive protein [hs CRP], fibrinogen), indicator carbohydrate metabolism (glucose),  ankle-brachial index,  stress-test, carotid plaques according to ultrasound were evaluated in all pts. Psychological RFs were evaluated using Hospital Anxiety and Depression Scale and DS-14 for type D personality. Results All pts were divided into 2 groups according to the CT angiography results: pts in the main group (n = 21) had any non-obstructive lesions or calcium score >0, pts in the control group (n = 31) had intact coronary arteries. The groups did not differ in age or gender. 26 multiple linear logistic models for any subclinical atherosclerosis were developed based on obtained diagnostic features. Taking into account R-square = 0.344 (p = 0.0008), the best fitting model was follows:  subclinical coronary atherosclerosis= -1.576 + 0.234 x SCORE ≥5%  + 0.541 x hs CRP >2 g/l + 0.015 x heart rate  (bpm) + 0.311 family history of premature CVD.  The developed algorithm had sensitivity of 63% and  specificity of 80%. Conclusions The created diagnostic model diagnostic model suggests the presence of subclinical coronary atherosclerosis in patients with high / very high CV risk with a high degree of probability. This easy-to-use method can be used in routine clinical practice to improve risk stratification and management choices in high-risk pts.

Influence of Microcalcifications on Stress Development Within a Vulnerable Plaque’s Cap

2011 ◽  
Author(s):  
Ze’ev Aronis ◽  
Erez Kanka ◽  
Eyass Massarwa ◽  
Rami Haj-Ali ◽  
Shmuel Einav
Keyword(s):  
Mechanical Characteristics ◽  
Plaque Rupture ◽  
Intraplaque Hemorrhage ◽  
Rapid Progression ◽  
Stress Concentrations ◽  
Coronary Syndrome ◽  
Vulnerable Plaques ◽  
Material Fatigue ◽  
Mechanical Factors ◽  
As Stress

Vulnerable plaques are inflamed, active, and growing lesions which are prone to complications such as rupture, luminal and mural thrombosis, intraplaque hemorrhage, and rapid progression to stenosis. Despite major advances in the prevention and treatment of this disease, it remains the leading cause of morbidity and mortality worldwide, accounting for 30% of all deaths globally [1]. The importance of stress/strain distribution is now well recognized in vascular pathophysiology, specifically in the mechanisms of plaque rupture. Finite element modeling (FEM) and advanced fluid structure interaction (FSI) studies can better characterize coronary stenosis coupling constitutive equations. Mechanical factors such as stress concentrations within a plaque (material fatigue), lesion characteristic (location, size, and composition), and flow patterns are involved in rupture of plaques. Assessment of local mechanical characteristics caused by plaque structure is important for identifying vulnerable plaques and may improve final estimation of the risk for coronary syndrome.

scholarly journals Current Advances in the Diagnostic Imaging of Atherosclerosis: Insights into the Pathophysiology of Vulnerable Plaque

2020 ◽  
Vol 21 (8) ◽  
pp. 2992
Author(s):  
Nataliya V. Mushenkova ◽  
Volha I. Summerhill ◽  
Dongwei Zhang ◽  
Elena B. Romanenko ◽  
Andrey V. Grechko ◽  
...  
Keyword(s):  
High Risk ◽  
Vulnerable Plaque ◽  
Plaque Rupture ◽  
Inflammatory Disorder ◽  
Arterial Tree ◽  
Non Invasive ◽  
Vulnerable Plaques ◽  
Risk Patients ◽  
Coronary Syndromes ◽  
Major Factors

Atherosclerosis is a lipoprotein-driven inflammatory disorder leading to a plaque formation at specific sites of the arterial tree. After decades of slow progression, atherosclerotic plaque rupture and formation of thrombi are the major factors responsible for the development of acute coronary syndromes (ACSs). In this regard, the detection of high-risk (vulnerable) plaques is an ultimate goal in the management of atherosclerosis and cardiovascular diseases (CVDs). Vulnerable plaques have specific morphological features that make their detection possible, hence allowing for identification of high-risk patients and the tailoring of therapy. Plaque ruptures predominantly occur amongst lesions characterized as thin-cap fibroatheromas (TCFA). Plaques without a rupture, such as plaque erosions, are also thrombi-forming lesions on the most frequent pathological intimal thickening or fibroatheromas. Many attempts to comprehensively identify vulnerable plaque constituents with different invasive and non-invasive imaging technologies have been made. In this review, advantages and limitations of invasive and non-invasive imaging modalities currently available for the identification of plaque components and morphologic features associated with plaque vulnerability, as well as their clinical diagnostic and prognostic value, were discussed.

Contemporary treatment patterns and short-term outcomes in men with very high-risk prostate cancer.

2016 ◽  
Vol 34 (2_suppl) ◽  
pp. 103-103
Author(s):  
Jeffrey J. Tosoian ◽  
Debasish Sundi ◽  
Brian Francis Chapin ◽  
Emmanuel S. Antonarakis ◽  
Meera Chappidi ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Clinical Trials ◽  
Lymph Node ◽  
High Risk ◽  
Local Treatment ◽  
Treatment Patterns ◽  
Short Term ◽  
Gleason Pattern ◽  
Very High

103 Background: Beginning in 2014, the National Comprehensive Cancer Network (NCCN) recognized very high-risk (VHR) prostate cancer (cT3b-T4, or primary Gleason pattern 5, or more than 4 biopsy cores with Gleason score 8-10, or multiple HR features) as a classification distinct from high-risk (HR) disease. Using prospectively collected institutional data, we describe contemporary treatment patterns and short-term outcomes in the VHR population. Methods: Men who underwent radical prostatectomy (RP) between January 2010 and June 2015 were identified using the Johns Hopkins RP database, and trends in management were compared across the study period. Pathological and short-term clinical outcomes were assessed in men with VHR cancer. Non organ-confined disease (NOCD) was defined as ≥ pT3 disease or lymph node positivity, persistent postoperative PSA as ≥ 0.2 ng/mL, and biochemical recurrence (BCR) as a PSA ≥ 0.2 ng/mL following an initial undetectable postoperative PSA. Results: During the study period, 4,954 men underwent RP, of which 161 (3.2%) men had VHR cancer at diagnosis. The annual proportion of men who underwent RP with VHR cancer increased over the study period (chronologically 1.8%, 1.0%, 3.3%, 4.1%, 5.6%, and 5.2%; p<0.001). Sixteen percent of men with VHR disease were enrolled in pre-surgical clinical trials, with an increase from 0% of men in 2010 to 19.1% in 2015 (p=0.11). At RP, 39% of the VHR cohort had seminal vesicle invasion, 26% had lymph node involvement, and a total of 74% had NOCD. Following surgery, 33% of men had PSA persistence, and 40% experienced either PSA persistence or BCR during follow-up (median 13.4 months). Of 136 men with at least one follow-up assessment, 15 (11.0%) developed metastasis; 33% of the cohort was treated with radiation therapy, 42% with androgen deprivation, and 15% with docetaxel. Conclusions: The VHR population carries the greatest risk of clinical progression following local treatment. Over the past five years, we have observed increasing surgical treatment and clinical trial enrollment at our institution. Continued assessment of post-operative interventions and outcomes will help to facilitate counseling and establish point estimates from which to power clinical trials.

scholarly journals Association of Radical Local Treatment with Mortality in Men with Very High-risk Prostate Cancer: A Semiecologic, Nationwide, Population-based Study

2017 ◽  
Vol 72 (1) ◽  
pp. 125-134 ◽  
Author(s):  
Pär Stattin ◽  
Fredrik Sandin ◽  
Frederik Birkebæk Thomsen ◽  
Hans Garmo ◽  
David Robinson ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
High Risk ◽  
Local Treatment ◽  
Population Based ◽  
Population Based Study ◽  
High Risk Prostate Cancer ◽  
Risk Prostate Cancer ◽  
Very High

Stress Concentrations of Vulnerable Plaques With a Composite Variable Core

2010 ◽  
Author(s):  
Eyass Massarwa ◽  
Aronis Ze’ev ◽  
Rami Eliasy ◽  
Rami Haj-Ali ◽  
Shmuel Einav
Keyword(s):  
Plaque Rupture ◽  
Necrotic Core ◽  
Intraplaque Hemorrhage ◽  
Plaque Morphology ◽  
Rapid Progression ◽  
Stress Concentrations ◽  
Coronary Syndrome ◽  
Fibrous Cap ◽  
Vulnerable Plaques ◽  
Life Threatening

Vulnerable plaques are inflamed, active, and growing lesions which are prone to complications such as rupture, luminal and mural thrombosis, intraplaque hemorrhage, and rapid progression to stenosis. It remains difficult to assess what factors influence the biomechanical stability of vulnerable plaques and promote some of them to rupture while others remain intact. The rupture of thin fibrous cap overlying the necrotic core of a vulnerable plaque is the principal cause of acute coronary syndrome. The mechanism or mechanisms responsible for the sudden conversion of a stable atherosclerotic plaque to a life threatening athero-thrombotic lesion are not fully understood. It has been widely assumed that plaque morphology is the major determinant of clinical outcome [1, 2]. Thin-cap fibroatheroma with a large necrotic core and a fibrous cap of < 65μm was describes as a more specific precursor of plaque rupture due to tissue stress.

Sign in / Sign up

Export Citation Format

Share Document