atrial fibrillation &stroke feb 2015 ngh
TRANSCRIPT
CARDIOGENIC STROKE IN
ATRIAL FIBRILLATION “ DUAL EPIDEMIC”
DR ASADULLAH SOOMROADULT CARDIOLOGIST
PRINCE SULTAN CARDIAC CENTREAL- HASSA KINGDOM OF
SAUDI ARABIAEmail;hssbasadsoomro&gmail.com
INTRODUCTIONUp to three million people world
wide have an atrial fibrillation –related strokes every year.
“that is one person every 12 seconds”.
Stroke is leading cause of
disability and 2nd most common cause of death worldwide.
INTRODUCTIONAtrial fibrillation is most common ( 1-2% USA)
sustained rhythm disorder in cardiological practice , has
multiple etiologies and
heterogenious clinical manifestations.
Afib is generally not life-threatening , but can lead to serious complications.
Its not a disease itself , but mysterious, devastating , and deadliest ,
“malignant syndrome.”yet frequently misinterpreted &
underestimated as , “benign” indeed .
Cont,
Atrial fibrillation & stroke have emerged as being among the most
common disorders afflicting the society.
Afib affecting about 5% of patients age >65 and 10% age >80 years.
They often occur together, and their combination is associated
with increased morbidity &
mortality compared with each disorder alone.
Prevalence of Cardioembolic stroke
Cardioembolic stroke accounts for
14-30% of ischemic strokes, with
potentially even higher rates in
developing & middle east countries.
50% to 69% patients with
cardioembolic stroke have atrial fibrillation.
People with atrial fibrillation are five times more likely to have strokes, and are generally
more severe and associated with greater disability than strokes from other causes .
Distribution of cardiac emboli
The heart was established as an important source for development of emboli when
Gowers, in 1875 described a case of middle cerebral artery and retinal
artery emboli.
Emboli from the heart are distributed evenly throughout the body according to the cardiac output, but more than 80% of symptomatic or clinically recognized emboli involve the
brain.Approximately 80% involve the anterior
circulation (ie, carotid artery territory) where as 20% involve vertebrobasilar distribution.
Overview of cardiac sources of Emboli
More than 20 specific cardiac disorders have been implicated in leading to brain
embolism.cardiac sources of emboli are classified into
major and minor risk categories.
Major sources carry a relatively high risk of initial and recurrent stroke
convincingly linked to a cardioembolic mechanism.
Minor –risk sources are frequent in general population, and the associated risk of initial
and recurrent stroke is either low or uncertain.
Actual Source Cardioembolic Conditions. ( major &
minor)
LV thrombus
Apical aneurysm, presence of thrombus, MI Dysfunctional ventricles,Dilated cardiomyopathy, hypertrabeculation/non compaction
LA thrombus
Thrombus in LAA, spontaneous echo contrast, LAA emptying velocity, mitral stenosis, interatrial septal aneurysm, in atrial fibrillation, flutter & Sick Sinus Syndrome.
Pelvic veins or Lower leg thrombus
ASD, atrial septal aneurysm, PFO,VSD and pulmonary AV fistula. ( Paradoxical)
Native valves RHD , mitral stenosis, Vegetations in IE ,tumor, MVP, mitral annular calcification, scelrotic calcific aortic valve.
Prosthetic valves
Thrombus, vegetations
Cardiac tumors
LA /LV myxoma, papillary fibroelastoma
Aorta Complex aortic plaque, atheroma
ETIOLOGY OF CARDIOEMBOLIC STROKE
Cardiac wall &
chamber abnormalti
es
CardiomyopathiesRWMA after MI
Ventricular aneurysm
Atrial septal aneurysm
Atrial massesASD & PFO
Cardiac wall &
chamber abnormalti
es
CardiomyopathiesRWMA after MI
Ventricular aneurysm
Atrial septal aneurysm
Atrial massesASD & PFO
Valve Disorders
Rheumatic Mitral & aortic
Prosthetic valves,
Infective Endocarditis,
Fibrous & fibrinous
endocardial lesions ( SLE)
Valve Disorders
Rheumatic Mitral & aortic
Prosthetic valves,
Infective Endocarditis,
Fibrous & fibrinous
endocardial lesions ( SLE)
Emboligenic Arrhythmias
Atrial Fibrillation/flutter
And“Sick sinus”syndrome
Emboligenic Arrhythmias
Atrial Fibrillation/flutter
And“Sick sinus”syndrome
What is stroke ?A stroke is the brain equivalent of a heart attack ( i-e myocardial infarction) . Blood must flow to and through the brain for it
to work properly.If this flow is blocked by blood clot ,the
brain losses its energy and oxygen supply ,causing brain damage that can
lead to disability or death.
Off all the stroke 87% are ischemic, 10% intracranial haemorrhage and 3% are due to subarrachnoid haemorrhage.
A cardiogenic stroke occurs when the heart pumps unwanted materials in to the brain circulation,resulting in occlusion of brain
blood vessel and damage to the brain tissue
Clinical features in suspected cardioembolic stroke
Although not sufficiently sensitive or specific to establish the diagnosis, the following clinical features help to distinguish cardiogenic embolism from other mechanisms of cerebral ischemia.
1) Decreased level of consciousness at onset ( 20-30%) of stroke.
2) Neurologic defecit of abrupt onset with maximal severity at onset ( 80%) Global aphasia without hemiparesis .
3) Rapid recovery from major hemiplegic defecit, due to reperfusion of the brain with early lysis of embolus in 5-12% patients.
Clinical features in suspected cardioembolic stroke
4) Onset of symptoms after a Valsalva provoking activity ie coughing & bending ,sexual intercourse. ( enhancing right to left shunt in PFO)
Cardiogenic emboli ( especially from chamber source are large) do not often affect the deep penetrating arteries or manifest as a lacunar syndrome.
Small emboli from valve ( Calcific As or infective endocarditis) can obstruct the
small penetrating arteries in ( 2 %- 5% ).
“ Neither seizures nor headache at onset is useful predictor of cardiogenic embolism.”
History and Physical findings in
suspected cardioembolic stroke1) Evidence of cardiac atrial dysrrhythmias2) Presence of thrill parasternal heave ,
abnormal apex beat, carotid bruit , gallop & cardiac murmurs.
3) Signs of Heart failure & neurologic defecit.4) Recent myocardial infarction5) Recent cardiac surgery , cadiac
interventional procedure & TAVI.
6) Signs of infective endocarditis & PVD.
7) H/O old stroke, prosthetic valve, Corrected CHD, DVT and pulmonary embolism
Symptoms of AfibSymptoms may be experienced on a
regular basis, intermitently or “not at all” : 1,2
( Fatigue, palpitations, dizziness, chest pain and breathlessness)
Many people with atrial fibrillation lack any symptoms.
( More than half of episodes of Afib are not felt by the patient)
Atrial fibrillation if present can be diagnosed using an electrocardiogram.
“Irregular rhythm without P wave”
Asymptomatic AfibAsymptomatic atrial fibrillation is a
substantial problem for indvidual health and for the health care system.
Despite being common , yet usually underestimated or even misinterpretated especially paroxysmal episodes .
• paroxysmal & silent A fib may cause stroke• It is frequent despite antiarrhythmic drugs or
catheter and surgical ablation.• It may cause cognitive dysfunction &
dementia.
How does atrial fibrillation lead to stroke
Blood Pools in the Atria
Blood Pools in the Atria
Blood clot forms
Blood clot forms
Whole or part of blood clot breaks off
Whole or part of blood clot breaks off
Blood clot travels to the brain and blocks a cerebral artery and
cause stroke
Blood clot travels to the brain and blocks a cerebral artery and
cause stroke
Non –Valvular Afib and strokes.
Non Valvular Afib is commonest cause of cardioembolic Stroke.The disorder is associated with thyroid disorders, hypertension
and heavy alcohol drinking.The risk of stroke is six times higher in patients with Afib. Risk rises with age( 1.5% at age 50yrs
to 25% at age of 80 yrs).
Stroke & intra cavitary thrombus in acute myocardial infarction.
In cavity clot formation occur in approximately one third of patients
within first two weeks after anterior MI. chronic ventricular dysfunction due to CAD, HTN and cardiomyopathy can also
develop ventricular thrombi.Stroke is less common among
uncomplicated MI, but may occur in 12% to 20% of complicated MI with LV
thrombus, especially active thrombus formation phase in 1-3 months, with
even substantial risk beyond acute phase in those who have persistent heart failure
with myocardial dysfunction or atrial fibrillation.
Stroke in valvular heart disease
Although the incidence of rheumatic fever and RHD has dramatically declined ,but RHD is still a very
important cause of brain embolism, particularly younger patients in
developing countries.
Recurrent embolism occurs in 30% to 60% of patients with rheumatic
mitral valve disease and a history of previous embolic event.
Stroke in valvular heart disease
60% to 65% recurrence develop
during first 6 months to one year.
Rheumatic mitral stenosis is more
frequent cause ( 93%) of brain embolism than mitral regurgitation ( 7%). IN MS it may occur even in
sinus rhythm and in 24% patients it may be asymptomatic ( Silent stroke).
Mitral valvuloplasty does not appear to significantly eliminate risk of
embolism.
91% of the clots
are hidden in
LA appendag
e
Atrial Fibrillation & Stroke in Grownup Congenital heart disease.
Thanks to the treatment successes of the past 40 years resulting in the saving of many lives of children with congenital
heart disease. Corrected Complex CHD population is growing all over the
world because of advancement in surgical skill, technology and early surgical
intervention.( post Fontan, mustard & TOF repair).
A considerable proportion of patient with cyanotic & eisenmenger syndrome have dysrrhythmias, endocarditis and
a stroke/TIA.
Atrial fibrillation & stroke in grownup congenital heart disease.
Because of extensive damage to atria in atrial switch procedure ,is
believed to be responsible for atrial fibrillation and flutter. sick sinus syndrome occurs in around 17% .The proportion of patients with
stroke /TIA in Fontan is quite large ( 25% in ten year) , Because of
coagulation abnormalties in some complex CHD , ( both thromboembolism & bleeding ).
MORE COMPLEX PATIENTS“FEW EXPERT CARDIOLOGISTS”
Most of the congenital heart disease are
seldom “ CURED” .
Cardiologists throughout the world still have little opportunity for exposure to adult
congenital heart disease ,and despite training recommendations , few trainees have the opportunity to see such patients
during their fellowship.Many cardiologists, therefore, have little understanding about the complexities of many postoperative “Residua and
Sequelae”
“born to be bad” ? In many ways , the answer is yes.
They are seldom “cured” by surgery and continue to have cardiac problems.
Much time , money ,and effort has been devoted to secure their survival, but
unfortunately, very little thought has been
given to providing for their long term care.
These survivors are extraordinarily courageous and usually, determined to work, contribute to
society, and be as normal as possible.
Cont,But , in adulthood , they often receive
no care or suboptimal care, perhaps the worst of any
cardiovascular subspeciality. The cardiology community serves them poorly ,and , as we look to the future we must make provision for lifelong care by trained physicians with
expertise in their complex problems.
But , there is serious shortage of professionals
And there are too few centres of excellence to act as the anchors for this care.
Three uncorrected adult congenital heart disease patiens with cardiogenic stroke.1) Fallots tetrallogy with brain abscess 2) ASD secundum with atrial fibrillation and stroke. 3) Eisenmenger VSD
with brain absess.
Iatrogenic Afib and strokes.
Stroke occurred in hospital in 0.3% after PCI, especially in patients with multiple co-morbidities,
emergency PCI & with IABP support.
Post CABG , Cholesterol embolization syndrome and aortic arch atheroma are also associated with
stroke and renal failure. High contrast use is also associated with renal failure and
stroke.
A fib occurs in 15-40% of patients after CABG and in 37-50% after valve surgery. 80% revert in 24 hours.
It is associated with three fold increase in the risk of stroke or TIA.
The incidence of post TAVI stroke is around 0.8-6%.
Iatrogenic Afib and strokes.
When there is a plane crash or terrorist attack, even a minor one ,it makes headlines in electronic &Print
media. There is a thorough investigation and
tragedy often yields important lesions for aviation industry.
Pilots and airlines thus learns how to do their their jobs more safely.
Iatrogenic Afib and strokes.
The medical world is far deadlier.
Medical mistakes kill enough people each week to fill many jumbo jets ,
but these mistakes go largely unnoticed by the world at large , and medical community rarely
learns from them. The same preventable mistakes are made over & over again and patients
left in dark about which hospitals have significantly better ( or worse)
safety records than their peers.
Iatrogenic Afib and strokes.
The problem is Vast .Roughly a quarter of all hospitalized
patients will be harmed by medical errors of some kind.
If medical errors were a disease they would be sixth leading cause of
death. Medical errors costs tens of billions a year in many countries.
More than 20-30% of all medications ,tests and procedures
are unnecessary.
Infective endocarditis & stroke
Stroke is the most common (10% to 45%) neurological complication of infective endocarditis
( vegetation>1omm) . Mycotic aneurysm in 1-5%.
Stroke most often occurs during uncontrolled infection, clinical spectrum has also changed .
Over the last decades Staphylococus aureus incidence has increased as compare to
strptococcus viridans.Strokes caused by staph aureus endocarditis tend to
occur early ,to be multiple and carry poor prognosis . Infected emboli may also cause
intracranial hemorrhage due to pyogenic arteritis.With early appropriate antibiotic treatment ,the risk
of recurrent embolism is low ( 0.3% per day) .There are no data to support use of anticoagulation for
primary or secondary prevention of stroke complicating infective endocarditis.
Stroke & paradoxical embolismThe most common potential intracardiac shunt is a residual patent
foramen ovale and associated inter atrial septal aneurysm. Recurrence is 2% 15%
An autopsy series have shown up to 30% of adults have probe patent PFO at necropsy.
The high frequency of PFO in normal adult has made it difficult for physicians to be certain in an indvidual stroke patient weather
1) A paradoxical embolism through PFO was cause of their stroke2) Or the PFO itself was merely an incidental finding during stroke
work up.Neuroimaging studies are non conclusive to the link between
PFO and embolic stroke.The review of a series 95 patients with paradoxical embolism
laid five criteria with high degree of certainty if > 4 .1) Situation that promote thrombosis of leg or pelvic veins.2) Increased coagulability ( contraceptives)3) Activity that provoke right to left shunting ( Valsalva)4) Pulmonary embolism shortly before or after neurologic
event.5) Absense of other clear causes of stroke.
45 year Indian male who
presented with acute stroke &
subsequent echocardiogram revealed large
LV myxoma and was operated.
Resected LA Myxoma
Resected LA Myxoma
Mortality of Cardioembolic Stroke
Cardioembolic infarct are the subtype of ischemic infarct with the highest in-hospital mortality during acute phase of stroke. In major series it
was 27.3% as compared with 0.8% for lacunar infarct and 21.7% for atherothrombotic stroke.
In recent study of 231 patients with cardioembolic stroke ,causes of death were non – neurological
in 54% ( Pneumonia, PE, sepsis& sudden death) . Neurological in 39.5% ( brain
herniation, recurrent & haemorrhagic infarction)Mortality in patients with early recurrence
( 9 patients 3.9% 5 cerebral & 4 peripheral) . Mortality within 7 days was
77.7% ( 7 out of 9 patients) as compared to remaining patients. Recurrent cerebral embolism mortality was 100% and in peripheral embolism
mortality was 50% ( Age,CHF,hemiparasis, Decrease consciousness)
“AfibBegetsAfib”
“StrokeBegetsStroke”
“Warning and a Challenge”
The CHA2DS2-VASc Index
Low risk 0 point, Intermediate risk2 points, High risk more than 2 pointsHigher the score ,the higher the risk of having a stroke. ( 0% to 15.2%)
Congestive heart failure/LV dysfunctionHypertensionAge > 75 yearsDiabetes mellitusStroke or TIA history
Age 65-74 yearsSex category ( female gender)
Vascular disease ( PVD,MI & aortic plaque)
Score1
1
2
1
21
1
1
Risk Factors
Medical management in cardioembolic strokes prevention
A fib can be diagnosed and managed by:
1) Oppurtunistic screening2) EKG & Holter3) Cardioversion to return heart to sinus rhythm.4) Anticoagulation to reduce risk of blood clots
which can cause stroke.5) Left atrial appendage exclusion.
Management differs according to type of AF and according to
specific patient characteristics.
Surgical Care in cardioembolic strokes
Alternative to medical therapy include,
1) Surgical maze operation or endovascular catheter guided ablation of arrhythmias to reduce risk of embolism
2) Thrombectomy 3) Valve replacement ( Endocarditis)4) Transcatheter device to occlude LA
appendage & thoracoscopic epicardial plication of LA.
5) Endovascular closure of PFO in cryptogenic stroke.
Atrial fibrillation Awareness And Risk Education
It Is a campaign dedicated to gaining greater recognition of atrial fibrillation as a major
international public health concern through exposing current misconceptions of condition
and focusing attention on the realities of the disease.
Payers,managers
Families & friends
ParamedicalPersonell
TARGET
Patients
Physicians
Campaign Goals• Raise awareness of Afib and its links to
stroke and other cardiovascular complications.
• Improve prevention, early diagnosis and optimal management of Afib.
• Highlight the impact that Afib can have on patient quality of life.
• Illustrate the socio-economic cost burden associated with Afib, its devastitating complications and hospitalization indeed.
• Educate health care professionals, patients, policy makers and adult population on detection & management of Afib.
Why is awareness of Afib low?
• Many people are unaware of the increased risk and potential life changing consequences of having an atrial fibrillation related stroke, many of which
can be prevented:• In the Afib AWARE international survey
46% of physicians agreed that their patients would not be able to explain Afib.
• A quarter of physicians thought Afib was too complex to explain during clinic visit or that they did not have enough time.
Why is stroke prevention in atrial fibrillation sub-optimally managedOnly half of diagnosed patients with
atrial fibrillation at risk of stroke receive anticoagulant therapy;
• Vitamin K antagonist are highly effective when INR is in range of 2.0-3.0.
• Fewer than half of patients on VKAs are controlled within narrow therapeutic range.
• Patients with very high risk of stroke ( e.g. elderly with comorbidities) are withheld oral anticoagulant due to fear of risk of bleeding.
We aim to move perception to reality
AF Perception
An isolated low risk Disease
Requiring symptom
Management and strokeprevention
AF REALITY
AF is severe CV disease
within the CV Continuum
AF has direct morbidity
And mortality Impact.
Underestimated
Stroke KnowledgeStroke Myths
Can not prevent StrokeCan not treat Stroke
Stroke is disease of elderlyRecovery happens for
few months after stroke
Stroke FactsStroke prevent
Stroke is treatableStroke affect anyoneRecovery occurs for
Through out life?
More than 25% of ischemic stroke in patients with A fib have causes other than cardiogenic emboli
( eg, aortic arch atheroma & intrinsic vascular disease) 58% stroke patient do not present during first 24 hour.
Silent MI and arrhythmias are common cause of death in stroke.
STROKEDISABILITY
STROKE DISABILITY
ConclusionsAfib is increasingly common, affecting
up to 2% of general populationThe number of people with Afib is set to
grow over time ,perhaps even doubling in the next 50 years.
Afib prevalence is likely to be underestimated because it can be
silent.Afib is a complex syndrome to
diagnose and manage.It has multiple etiologies, yet
potentially preventible & reversible complications ( MI, HF, stroke & SCD).
ConclusionsAfib awareness & education is available but
isn,t sufficient to targeted population especially in local languages.
Afib results in a substantial cost of illness because it uses significant resources across primary to terrtiary care. In
particular hospitalizations are expensive and this is key drive of the cost of Afib.
Appropriate diagnosis , management and prevention of complications, particularly the use of medicines can lead to reduced
demand for expensive hospital care.Afib results in substantial loss of work &
economy indeed
ConclusionsDuring the past two decades enormous progress has
been made in the diagnosis of cardioembolic disorders and in establishing evidence –based
recommendations for the primary and secondary prevention of stroke.
Because Afib is by far the commonest cause of cardioembolic stroke,the mortality,disability,and cost related to stroke will mainly be decreased by
advances in detection and treatment of Afib.The future task is to develop more sensitive methods
to identify paroxysmal Afib.What is to be learned from the pathogenesis of stroke
after PCI? Avoiding stroke continues to be good reason to chose primary PCI over thrombolytics for
acute MI.Cardiologist must flush catheters throughly, minimize
catheter manipulation and use minimal contrast medium during PCI.
ConclusionsDespite tremendous advancement yet
physicians are confronted with complex common scenarios .
Numerous unanswered questions persist.
Ischemic stroke may be the presenting manifestation of atrial fibrillation in some patient, while in others it may
occur despite appropriate antithrombotic prophylaxis.