This document discusses various methods for quantifying intracardiac shunts in patients with congenital heart lesions. It describes invasive oximetry and indicator dilution techniques as well as noninvasive Doppler echocardiography methods. For echocardiography, it outlines techniques for quantifying left-to-right shunts using pulmonary and aortic flow measurements, as well as a simplified method using diameter ratios. It also discusses limitations and sources of error for these quantification methods.
preop TEE assessment of atrial septal defect is very important for making decision for device closure, properly assessed adequate rims of ASD will reduce risk of device embolization to almost nil.
preop TEE assessment of atrial septal defect is very important for making decision for device closure, properly assessed adequate rims of ASD will reduce risk of device embolization to almost nil.
Percutaneous Balloon Mitral Valvuloplasty (PBMV) is a procedure to dilated the mitral valve in the setting of rheumatic mitral valve stenosis. A catheter is inserted into the femoral vein, advanced to the right atrium and across the interatrial septum. Then the mitral valve is crossed with a balloon and it is inflated to relieve the fusion of the mitral valve commissures effectively acting to increase the mitral valve area and reduce the degree of mitral stenosis. Mitral regurgitation is a potential complication and thus PBMV is contraindicated if moderate or severe regurgitation is present. The Wilkins score examines mitral valve morphology and is determined via echocardiography to assess the likelihood of using PBMV based on certain echocardiographic criteria.
Based on the principle that the distal coronary pressure measured during vasodilation is directly proportional to maximum vasodilated perfusion.
FFR is defined as the ratio of maximum blood flow in a stenotic artery to maximum blood flow in the same artery if there were no stenosis.
FFR is simply calculated as a ratio of mean pressure distal to a stenosis (Pd) to the mean pressure proximal stenosis, that is the mean pressure in the aorta (Pa), during maximal hyperaemia.
Our concepts of heart disease are based on the enormous reservoir of physiologic and anatomic knowledge derived from the past 70 years' of experience in the cardiac catheterization laboratory.
As Andre Cournand remarked in his Nobel lecture of December 11, 1956, the cardiac catheter was the key in the lock.
By turning this key, Cournand and his colleagues led us into a new era in the understanding of normal and disordered cardiac function in huma
Percutaneous Balloon Mitral Valvuloplasty (PBMV) is a procedure to dilated the mitral valve in the setting of rheumatic mitral valve stenosis. A catheter is inserted into the femoral vein, advanced to the right atrium and across the interatrial septum. Then the mitral valve is crossed with a balloon and it is inflated to relieve the fusion of the mitral valve commissures effectively acting to increase the mitral valve area and reduce the degree of mitral stenosis. Mitral regurgitation is a potential complication and thus PBMV is contraindicated if moderate or severe regurgitation is present. The Wilkins score examines mitral valve morphology and is determined via echocardiography to assess the likelihood of using PBMV based on certain echocardiographic criteria.
Based on the principle that the distal coronary pressure measured during vasodilation is directly proportional to maximum vasodilated perfusion.
FFR is defined as the ratio of maximum blood flow in a stenotic artery to maximum blood flow in the same artery if there were no stenosis.
FFR is simply calculated as a ratio of mean pressure distal to a stenosis (Pd) to the mean pressure proximal stenosis, that is the mean pressure in the aorta (Pa), during maximal hyperaemia.
Our concepts of heart disease are based on the enormous reservoir of physiologic and anatomic knowledge derived from the past 70 years' of experience in the cardiac catheterization laboratory.
As Andre Cournand remarked in his Nobel lecture of December 11, 1956, the cardiac catheter was the key in the lock.
By turning this key, Cournand and his colleagues led us into a new era in the understanding of normal and disordered cardiac function in huma
Coronary Calcium and other CVD Risk Biomarkers: From Epidemiology to Comparat...CTSI at UCSF
Presented by Philip Greenland, MD, at UCSF's symposium "The Role of Risk Stratification and Biomarkers in Prevention of Cardiovascular Disease" in Jan 2012.
Various coronary physiological measurements can be made in the cardiac catheterization laboratory using sensor-tipped guidewires; they include the measurement of poststenotic absolute coronary flow reserve, the relative coronary flow reserve, and the pressure-derived fractional flow reserve of the myocardium. Ambiguity regarding abnormal microcirculation has been reduced or eliminated with measurements of relative coronary flow reserve and fractional flow reserve. The role of microvascular flow impairment can be separately determined with coronary flow velocity reserve measurements. In addition to lesion assessment before and after intervention, emerging applications of coronary physiology include the determination of physiological responses to new pharmacological agents, such as glycoprotein IIb/IIIa blockers, in patients with acute myocardial infarction. Measurements of coronary physiology in the catheterization laboratory provide objective data that complement angiography for clinical decision-making
Diagnosis, management, workup in a case of Takayasu's arteritis. Definition, synonyms, history, epidimiology, pathophysiology, etiology of Takayasu's arteritis.
A case of missed diagnosis. Presentation can be in form of heart failure. Differentials can be of Constrictive pericarditis. Restrictive cardiomyopathy/Endomyocardial fibrosis, DCM. This presentation contains clinical presentation, differentials, hemodynamics of cath study, echocardiogrpahy in a case of CP
Hemodynamics in echo lab by Dr. Ranjeet S.PalkarRanjeet Palkar
ECHO LAB AND CARDIOVASCULAR HEAMODYNAMICS. A simple cost effective,non invasive approach which when used appropriately can be boon for physicians and cardiologists in diagnosis and prognostication.
Singular value decomposition filtering in high-frame-rate cardiac vector flow...journalBEEI
Dysfunction of the left ventricle (LV) weakens the cardiac function and affects the physical activity. Echocardiagraphy has been used to visualize the blood flow dynamics and to evaluate the cardiac function. However, the signal processing to suppress the clutter signals should be employed. In this study, we employed the singular value decomposition (SVD) clutter filtering to obtain the cardiac blood speckle images. We also employed the adaptive thresholding metric to determine the proper cutoff values at each phase during the cardiac cycle. Moreover, we employed a depth-dependent SVD clutter filter for more accurate estimation of the cardiac blood echo signals. The 2D blood flow velocity vectors were estimated by applying the block matching method to obtained blood speckle images. The obtained results show that the proposed filter suppressed the clutter signals from left ventricular wall significantly, and the contrast-to-noise ratio (CNR) was improved from -0.5 dB to 13.8 dB by the proposed SVD clutter filtering.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
263778731218 Abortion Clinic /Pills In Harare ,ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group of receptionists, nurses, and physicians have worked together as a teamof receptionists, nurses, and physicians have worked together as a team wwww.lisywomensclinic.co.za/
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
Follow us on: Pinterest
Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
2. Introduction
Majority of the congenital lesions are asso. with
intracardiac shunts.
Detection, localisation and quantification of shunts –
integral part of hemodynamic evaluation of these
patients.
Quantification of shunts by:
Invasive
Noninvasive methods.
6. 2 –D Echocardiography:
direct visualization of any communication and their
shunting
excellent for localization of shunt
limited in the ability to quantify shunt
Indirect estimations
ASD with large shunting
RA, RV dilated
diastolic septal flattening
VSD with large shunting
LA, LV dilatation
Systolic and diastolic septal flattening
7. Contrast Echo
Agitated saline
Detection of small R L shunts
Large left to right shunts may cause a negative
contrast jet in the Rt. atrium
8. Doppler echocardiography
Most of the studies were done in ASD & VSD.
Based on the measurement of flow across the valves
or the defect itself.
Based on the formula that flow can be calculated
from CSA & VTI.
9. Volumetric flow measurement requires
- calculation of temporal mean flow velocity and
cross sectional area
- velocity profile is uniform across the vessel
- single sampling of the flow velocity in the center
of the vessel is recorded
To calculate
computerised calculation of the area under the
doppler curve/ flow period
10. For systemic flow
Aortic velocity is recorded from the apical view.
Vessel diameter is measured from the parasternal long
axis view.
11. Pulmonary blood flow:
Pulm. mean velocity is recorded from the
parasternal short axis view
In case of large shunt and a shunt located close
to PA, the doppler tracing shows spectral
broadening or signs of disturbed flow, in such
cases uniform velocity cannot be assumed
Doppler tracing cannot be used if any PS is
present.
12. Measurement of the cross sectional area
- at the valve annulus (as it is the flow limiting
point of the vessel)
- measurement is made from the inner edge to
the inner edge.
- diameter is measured at the early systole –
time when vessel is at peak systolic dimension.
- flow velocity should be measured at same
location
13. Methods:
1.Qp/Qs calculation from flow velocity (velocity
time integral) and cross sectional area
Qp/Qs = Area of Pa x VTI
Area of Aorta x VTI
Sanders et al used pulmonary flow with good
correlation , r=0.85.
Barron et al used Mitral flow with better
correlation , r= 0.9 vs 0.69.
14. 2. Simplified method - the square of the pulmonary
to aortic diameter ratio was substituted for the
area ratio and the flow peak velocity ratio for the
velocity time integral.
Qp/Qs = Vel. Pk PA x r2
Vel. Pk Ao x r2
r= radius / diameter
square of the ratio of the pulmonary to aortic
luminal diameter (or radius)is used instead of
vessel areas.
15. 3. Qp/Qs = (pulm + mitral flow)/2
(tricuspid + aortic flow)/2
Assumption that tricuspid and aortic flow
represent systemic flow and pulmonary &
mitral flows represent pulmonary flow.
Maximal diameter of mitral and tricuspid
valve annulus is measured during diastole in
an apical 4 –chamber view & area calculated
assuming the annulus to be circular.
Laborious & time taking.
Combines measurements from all the 4 valves
but was not shown to be better than the
previous 2.
16. 4. Qp/Qs = Shunt flow + aortic flow
aortic flow
Shunt (VSD) flow as the product of the VTI
and color-derived cross-sectional area of VSD jet
measured at its narrowest point.
This method does not use the pulmonary flow &
outflow diameter which are more variable.
17. Difficulties : It is assumed that
1. The defect is circular.
2. The size does not vary during systole.
3. No angle correction is needed.
4 . Flow velocity is uniform across the orifice.
18. Most studies show moderate correlation of
doppler techniques with oximetry data.
Sabry et al, studied above 4 methods with
cardiac cath calculated shunts.
First 2 methods showed moderate correlation
( r=0.54 & 0.56 ). Correlation improved
when large VSDs were excluded (r=0.62 &
0.66 ).
3rd
method showed no better correlation & it
was more time taking (r =0.57).
4th
method showed best correlation (r =0.82).
When large VSDs were excluded it was r = 0.9.
19. Sources of error
Mainly from the assumptions made
1) assumption that velocity profile is uniform
through out the cross sectional area
2) alignment of the doppler beam with the
direction of the flow ( angle < 200
)
3) turbulent flow in the vessels mainly in the
PA.
4) inaccuracy in measurement of cross
sectional area of vessels
- PA dimensions vary significantly during
cardiac cycle
20. 5) errors in calculation because of presence of
additional defects
e.g PDA present downstream from the PA
6) semilunar valve regurgitation results in
overestimation of flow because of failure to measure
the regurgitant volume
7) All these methods overestimate the shunt in large
VSDs.
8) Quantification of PDA is not accurate due to the
turbulent flow across the defect & difficulty in
measuring the flow distal to the shunt.
21. Quantification of ASD
TTE estimation of ASD diameters & shunt
quantification by cath showed only fair correlation
(r=0.56).
• The size of the defect by transesophageal Doppler
color flow mapping correlated fairly well with the
size estimated at surgery (r = 0.73 ).
Other measurements by TTE for ASD are –
- RV/LV diameter (r=0.64)
- Area of PA (r=0.62)
- RV volume (r=o.71)
- PA/Ao (r=0.89)
22. Doppler colour flow mapping by
TEE
• Area of the ASD- calculated by assuming it to be
circular and taking the maximal Doppler color flow jet
width at the defect site as its diameter.
• The pulsed Doppler sample volume is to be placed
parallel to the shunt flow direction at the defect site to
obtain the mean velocity and flow duration.
23. • From these values, the shunt volume can
calculated as a product of the defect area, mean
velocity, flow duration and heart rate.
• The calculated shunt flow volume obtained by
transesophageal study showed a good correlation
with shunt flow volume (r = 0.91) and pulmonary to
systemic blood flow ratio (r = 0.84) obtained at
cardiac catheterization.
24. R L shunt quantification
Aortic flow + VSD flow = Input to RV
Pulmonary flow + R L shunt = output from RV.
Hence R L shunt = Aortic flow + VSD flow –
Pulmonary flow.
Only fair correlation found with Cath data (r = 0.61 –
0.77 )
25. Automated cardiac flow
measurement method
ACM method – using spatial and temporal
integration of colour Doppler profiles .
Method velocity profile in a region of interest
set on the flow tract is detected in each frame ,
imaged & recorded on the image memory
Flow volume rate is calculated by integration of
the velocity profile
Stroke volume is measured by temporal
integration, throughout the systolic period.
26. ACM method:
Advantages:
Quick and requires only two manual procedures.-
selection of systolic period in the stored image
memory, positioning at the area of interest
Calculations are done without tracing the
Doppler wave form to measure VTI
No need to measure area of outflow tract, because
the edge of the color profile is detected as the width
of the flow tract.
27. ACM method
ACM uses velocity profile across the flow tract
diameter, while in conventional pulsed Doppler
method the spectral velocity from a centrally
placed sample point is measured
Flow rate at each frame is temporally integrated
for the stroke volume calculation
Thus this method requires fewer assumptions
than pulsed Doppler method.
28. Martin et al found strong correlations between
ACM and invasive QP/QS ratio and the agreement
with invasive data was better using ACM than
using conventional echocardiographic method ( r
= 0.91 )
The only restriction remains to select manually
the systolic period and to carefully choose the
region of interest.
Gain must be optimised, allowing to see only one
colour throughout the outflow tract
29. Avoids the potential error of conventional PWD
method for the calculation of pulmonary output,
linked to the difficulty of measuring the exact
pulmonary diameter.
This method was applied to ASD & VSD with better
correlation .
30.
31. Principle: oxygenated blood shunted from left
side of the heart to the rt cause an abnormal
increase (step – up) in the oxygen content or
saturation of blood in the chamber into which
shunting occurs
Dexter et al, max. increase in oxygen content
from,
RV to PA - 0.5 ml/dl
RA to RV - 1.0 ml/dl
SVC to RA - 2.0 ml/dl
32. Barratt -Boyes and Wood suggested that multiple
blood samples to be obtained from each Rt. heart
chamber.
Data to be averaged before applying Dexter
Criteria
Advantages
- easy to perform, results available immediately
- can ascertain the site of shunt
- magnitude of the shunt can be calculated
33. Detection of left to right shunt
Level of
shunt
Mean O2 sat % in
distal chambers
(Highest value in
proximal
chambers)
Mean O2
vol. % in
proximal
chambers
(Highest
value in
distal
chambers)
Min Qp/Qs
reqd. for
detection at
3L/min/m2
Possible causes
of step up
Atrial
(SVC/IVC
to RA)
≥7 (≥11) ≥1.3 (≥2.0) 1.5 – 1.9 ASD, RSOV,
VSD with TR,
coronary fistula
to RA,
anomalous PV
drainage
Ventricular
(RA to RV)
≥5 (≥10) ≥1.0 (≥1.7) 1.3 – 1.5 VSD, PDA with
PR, Primum
ASD, coronary
fistula to RV
34. Detection of left to right shunt
Level of
shunt
Mean O2 sat % in
distal chambers
(Highest value in
proximal
chambers)
Mean O2
vol. % in
proximal
chambers
(Highest
value in
distal
chambers)
Min Qp/Qs
reqd. for
detection at
3L/min/m2
Possible causes
of step up
Great
vessel
(RV to PA)
≥5 (≥5) ≥1.0 (≥1.0) ≥1.3 PDA, Aorta-
pulmonic
window,
Aberrant
coronary artery
origin
Any level
(SVC to
PA)
≥7 (≥8) ≥1.3 (≥1.5) ≥1.5 All of the above
35. Detection of left to right shunt
Chambers
sampled
Single
Sample
Multiple
samples
SVC – RA 7% 5%
RA – RV 5% 3%
RV – PA 4% 3%
PV/LA –
LV/SA
-3% -2%
36. Oximetry – limitations:
It lacks sensitivity – i.e. does not allow detection of
small left to right shunts
Requirement of steady state during collection of blood
samples
Calculation of Mixed venous saturation: Normal
variability of blood oxygen saturation in the Rt heart
chambers is strongly influenced by the magnitude of
systemic blood flow.
Higher levels of systemic blood flow higher mixed
venous saturation blunting of inter-chamber
variability.
37. Step up in oxygen content of the receiving chamber
depends also on the oxygen carrying capacity of blood
i.e. Hb conc.
Depends on the associated lesions also – like TR, PR.
38. Precautions
Samples at multiple sites to be obtained rapidly ,
should take < 7 min.
O2 saturation data rather than O2 content are
preferable,
Comparision of mean values is preferable to
highest values.
When the systemic blood flow at rest is low,
exercise shoud be used.
At higher FiO2 the dissolved O2 should also be
considered.
40. Carter formula
Determines the left to right shunting.
Best used when there is a smooth downstroke
They can detect a minimum shunt of 25 – 30%.
Simplified formula of Victoria & Gessner is used when
there is no smooth transition.
42. %Qs = BT1 x P1x 100
BT1xP1 + 0.44xT2xP2
%Qs = percentage of systemic blood flow due to Rt to
Lt shunt.
PC1 = height of first peak.
BT1 = bulid up time from appearance to first peak.
T2 = time from injection to P2.