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Transcript
WORKPLACE SAFETY AND INSURANCE
APPEALS TRIBUNAL
DECISION NO. 1987/14
BEFORE:
G. Dee: Vice-Chair
HEARING:
October 30, 2014 at Toronto
Written
DATE OF DECISION:
November 14, 2014
NEUTRAL CITATION:
2014 ONWSIAT 2462
DECISION(S) UNDER APPEAL: WSIB Appeals Resolution Officer (ARO) decision dated
September 26, 2011
APPEARANCES:
For the worker:
S. Cirillo, Paralegal
For the employer:
N/A
Interpreter:
N/A
Workplace Safety and Insurance
Appeals Tribunal
Tribunal d’appel de la sécurité professionnelle
et de l’assurance contre les accidents du travail
505 University Avenue 7th Floor
Toronto ON M5G 2P2
505, avenue University, 7e étage
Toronto ON M5G 2P2
Decision No. 1987/14
REASONS
(i)
[1]
Issues
The worker seeks entitlement for a heart attack that occurred at work on June 10, 2008.
(ii)
Background
[2]
The worker was at work and working as a painter when he suffered a heart attack
(myocardial infarction) on June 10, 2008. The worker was 66 years old at the time.
[3]
The worker survived the heart attack but he experienced anoxic brain injury secondary to
the heart attack and has not been able to communicate about the circumstances of his heart
attack.
[4]
[5]
[6]
[7]
[8]
The circumstances surrounding the occurrence of the worker’s heart attack have been
investigated by a WSIB investigator. There are also reports from the ambulance attendants who
first treated the worker following his heart attack.
The worker, through his family members, has requested entitlement for the heart attack.
The WSIB denied the worker’s claim and also denied the worker’s appeal of that denial.
The final decision of the WSIB is contained in the Appeals Resolution Officer’s decision of
September 26, 2011.
The worker now appeals to the Appeals Tribunal.
The worker was self-employed with personal coverage from the WSIB. There is therefore
no employer to participate in the appeal.
(iii) Analysis
(a)
[9]
Decision overview
The worker’s appeal is denied.
[10]
Medically, it is commonly accepted that heart attacks that occur without an external cause
(electrocution, trauma, anesthesia) generally occur in individuals who are experiencing coronary
artery disease (CAD). These heart attacks may occur with or without significant physical
exertion and whether or not the individual is aware that they have CAD.
[11]
It is recognized, however, that unusual physical exertion may in some circumstances
bring on a heart attack. WSIB policy and WSIAT decisions recognize this possibility and the
presence of unusual physical exertion prior to the occurrence of a heart attack may be significant
in determining a worker’s entitlement for a heart attack.
[12]
[13]
In the present appeal my review of the information regarding the worker’s heart attack
leads me to conclude that the worker was not involved in unusual physical exertion at the time of
the heart attack.
Furthermore, there is evidence from a co-worker and from the ambulance attendant that
the worker was experiencing symptoms of cardiac difficulty in the period prior to his heart
attack.
Page: 2
Decision No. 1987/14
[14]
Finally, I note that there is no medical opinion present in the file that indicates that the
worker’s activities at the time of his heart attack were a significant cause of the worker’s heart
attack at that time.
[15]
The evidence and analysis that I have relied upon to reach the above conclusions is
specified in greater detail below.
(b)
[16]
[17]
[18]
Background information on heart attacks
The Tribunal has developed a Medical Discussion Paper dealing with heart conditions.
This paper was prepared by Dr. W.J. Kostuk a professor Emeritus, in the Cardiology Division of
Department of Medicine at the University of Western Hospital.
The opinions expressed in the Tribunal’s Medical Discussion Papers do not necessarily
represent the views of the Tribunal. However, Panels may consider and rely on the medical
information provided in the Discussion Paper subject to the need to recognize that it is always
open to the parties to an appeal to distinguish a Discussion Paper and challenge it with
alternative evidence. See Kamara v. Ontario (Workplace Safety and Insurance Appeals
Tribunal) [2009] O.J. No. 2080 (Ont Div Court).
Dr. Kostuk’s Medical Discussion Paper is present in the appeal record and the contents of
that paper have not been contradicted by any other evidence in the appeal record. The paper
includes the following information about the nature of coronary artery disease (CAD) and heart
attacks (or myocardial infarctions):
CORONARY ARTERY DISEASE - ANGINA, UNSTABLE ANGINA,
MYOCARDIAL INFARCTION
Introduction
Coronary artery disease (CAD) is a major cause of death and disability in Canada. CAD
or atherosclerosis is a chronic disorder involving the blood vessels (coronary arteries) that
feed blood to the heart muscle. With this disease there are stable and unstable periods.
Anatomy & Physiology
The heart (figure 1) is a pump composed of four chambers - 2 of which receive blood
(atria) & 2 which pump blood (ventricles). Blood returns from the body to the right
atrium & is pumped into the lungs by the right ventricle. In the lungs, oxygen is added to
the blood & carbon dioxide removed. Blood then flows into the left atrium & is then
pumped by the left ventricle into the aorta & delivered to the entire body. The coronary
arteries (right and left) are the first branches of the aorta and bring the oxygenated blood
to the heart muscle itself. To pump blood to the body, the left ventricle has the most
muscle in the heart and is the chamber most affected by a heart attack.
Angina, Unstable Angina, Myocardial Infarction
1. Causation/Evolution:
Over a long time, the vessel wall becomes thickened with buildup of cholesterol and
narrows the lumen. These buildups in the wall or plaques are called atherosclerosis.
Plaque in the arteries can become so thick that it severely restricts the flow of blood to
the heart. This can result in recurrent chest pain (angina) that’s triggered by exertion and
relieved by rest. No heart muscle death occurs.
Occasionally a plaque will rupture, triggering the formation of a blood clot. This clot can
block blood flow to the heart. This sudden interruption in blood flow leads to inadequate
oxygen delivery to the heart muscle and if persistent, myocardial necrosis (heart muscle
Page: 3
Decision No. 1987/14
death) or infarction ensues. A heart attack can occur anytime — at work or play, while
one is resting, or while one is active. Some heart attacks strike suddenly, but many people
who experience a heart attack have warning signs and symptoms (unstable angina) hours,
days or weeks in advance.
2. Clinical Presentations:
There are two types of angina-stable and unstable.
Stable angina is the result of a temporary, insufficient blood flow to the heart muscle due
to a narrowed vessel impairing flow. Chest pain occurs in a predictable fashion such as
during physical activity or emotional stress when the heart is working harder and
requiring additional blood flow. Cessation of the precipitating factor results in restoration
of adequate blood flow and the symptoms quickly subside without any damage to the
heart.
Unstable angina results from the sudden rupture of a plaque, which precipitates a rapid
accumulation of platelets at the rupture site with abrupt restriction of blood flow in the
coronary artery. Consequently, symptoms occur suddenly, in an unexpected or
unpredictable fashion. The symptoms may be new, prolonged, more severe, or occur with
little or no exertion. Unstable angina is less responsive to nitroglycerin medication than
stable angina. The accumulation of platelets and obstruction to blood flow can result in a
myocardial infarction.
Myocardial infarction (MI) or a heart attack implies myocardial cell death; this occurs as
result of prolonged ischemia (impairment of blood flow with resultant inadequate oxygen
delivery to the heart muscle). With the onset of myocardial ischemia, cell death is not
immediate, but takes a finite period to develop : as little as 20 minutes. Complete death of
all myocardial cells at risk requires at least 2-4 hours or longer.
Finally, CAD and its sequelae account for 80% of sudden cardiac deaths. While this may
occur in individuals with unrecognized CAD, a history of prior infarction is present in
about 50%. The most common mechanism is ventricular tachyarrhythmia (a catastrophic
failure of coordinated electrical activity with prompt loss of cardiac pumping function
and death).
3. Risk factors:
The presence of certain factors, called coronary risk factors, increase an individual’s risk
of a heart attack. These factors contribute to the unwanted buildup of the deposits that
narrow the arteries throughout the body, including the arteries to the heart.
Coronary risk factors include:
Tobacco smoke. Smoking and long-term exposure to second hand smoke damage the
interior walls of arteries and increases the risk of blood clots forming.
High blood pressure. Over time, high blood pressure can damage the arteries and
accelerate atherosclerosis. The risk of high blood pressure increases with age and obesity.
High blood cholesterol or triglyceride levels. Cholesterol is a major part of the deposits
that can narrow arteries. A high level of the wrong kind of cholesterol increases the risk
of a heart attack. Low-density lipoprotein (LDL) cholesterol (the “bad” cholesterol) is
most likely to narrow arteries. A high LDL level is undesirable and is often a byproduct
of a diet high in saturated fats and cholesterol. A high level of triglycerides, a type of
blood fat related to diet, also is undesirable. However, a high level of high-density
lipoprotein (HDL) cholesterol (the “good” cholesterol), which helps the body clean up
excess cholesterol, is desirable and lowers the risk of heart attack.
Page: 4
Decision No. 1987/14
Lack of physical activity. An inactive lifestyle contributes to high blood cholesterol
levels and obesity. Conversely, people who get regular aerobic exercise have better
cardiovascular fitness, which decreases their overall risk of heart attack. Exercise is also
beneficial in lowering high blood pressure.
Obesity. Obese people have an excess of body fat (a body mass index -BMI of 30 or
higher). BMI is a measure of body fat based on height and weight that applies to adult
men and women. Abdominal obesity as measured by waist circumference - men >102 cm
and women >88 cm - is associated with an elevated risk of CAD. Obesity raises the risk
of heart disease because it’s associated with high blood cholesterol levels, high blood
pressure and diabetes.
Diabetes. Diabetes is the inability of the body to adequately produce or respond to
insulin properly. While diabetes can occur in childhood, it appears more often in middle
age and in overweight individuals.
Stress. An individual’s response to stress may increase the risk of a heart attack. Under
stress, an individual may overeat or smoke from nervous tension. Too much stress, as
well as anger, can also raise blood pressure.
Alcohol. Alcohol in moderation helps to raise HDL levels and can have a protective
effect against heart attack. Men should have no more than two drinks a day, and women
should have no more than one. Excessive drinking can raise blood pressure and
triglyceride levels, increasing the risk of a heart attack.
Family history of heart attack. If family members have had heart attacks at an early age
(<55 years), an individual’s risk is greater. This may be related to genetic conditions that
raise blood cholesterol levels or blood pressure.
Increasing age
Male sex. While men are generally at greater risk than women of heart attacks, women
are not immune and their risk increases after menopause and in the presence of the above
risk factors.
4. Symptoms:
Common signs and symptoms of angina, unstable angina and heart attack include:

pressure, fullness or a squeezing pain in the center of the chest

pain or discomfort that extends beyond the chest to the shoulders, arms, back, or
jaw

discomfort in the upper abdomen

shortness of breath
Typically, the symptoms of stable angina will subside promptly with stopping physical
activity and resting or taking nitroglycerin. If the symptoms persist for more than 15
minutes, are more intense, rapidly accelerating and associated with other symptoms
(sweating, impending sense of doom, dizziness or fainting, nausea and vomiting) or not
relieved with nitroglycerin , medical attention should be sought as the symptoms may be
those of unstable angina or a heart attack rather than stable angina.
…
[19]
The paper also has the following to state about physical exertion and heart attacks:
Physical stress (i.e., exertion) is, in general, good and is to be encouraged. The lack of
physical stress – a sedentary lifestyle contributes to development of CAD. If an
individual already has CAD then excessive physical exertion may precipitate angina or
even a heart attack. Numerous studies over several decades have shown the role of heavy
Page: 5
Decision No. 1987/14
exertion — from snow shoveling to recreational exercise — in triggering sudden
myocardial events and the protective role of regular exercise in preventing them.
Firefighters have episodic exposure to extreme levels of physical exertion, and they face
occupational hazards that may add to or amplify their risk of death due to cardiovascular
causes. These hazards include chemicals, thermal and emotional stress. Overall,
firefighters do not have an excess risk of dying from heart disease. However, emergency
firefighting duties have been associated with a risk of death from coronary heart disease
that is markedly higher than the risk associated with non-emergency duties. The majority
of these individuals had received a diagnosis of vascular disease or had a high prevalence
of coronary risk factors.
While individuals who exercise rarely may be more likely to suffer a heart attack after
strenuous exertion than those who exercise regularly, the absolute risk of a cardiac event
after any single bout of activity remains rare. In summary, physical stress does not cause
CAD and while angina is commonly associated with exertion, heart attacks do not usually
happen during exercise.
(c)
WSIB policy and Tribunal case law
[20]
WSIB policy and Tribunal case law reflect the general understanding of the nature of
heart attacks that is contained in the Medical Discussion Paper.
[21]
WSIB policy on heart attacks is found in Operational Policy Manual Document No.
15-03-10 and provides that entitlement for a heart attack may be granted as work related when a
causal relationship is shown between the cardiac condition and an accident at work, or the
cardiac condition is established as a disablement arising out of and in the course of employment.
Entitlement is accepted on an aggravation basis where there has been “unusual physical exertion
for the individual and/or acute emotional stress with no significant delay in the onset of
symptoms”.
[22]
The Appeals Tribunal must apply WSIB policy in accordance with section 126 of the
Workplace Safety and Insurance Act (the Act).
[23]
[24]
As noted by the worker’s representative, Tribunal decisions such as Decision No. 720/11
have considered the application of the presumption clause that is found in subsection 13(2) of the
Act which provides that where an accident occurs in the course of the worker’s employment, it is
presumed to have arisen out of the employment unless the contrary is shown.
Decision No. 720/11 states the following about the effect of the presumption clause
where it applies:
I agree that the applicable standard of proof in cases where the presumption applies
remains “on a balance of probabilities”. There is no higher standard of proof which
applies for the purpose of rebutting the presumption, than the standard which generally
applies in proceedings under the Act. It follows that, as a result of the presumption, the
question to be determined in this appeal is whether it is probable that the worker’s
activity in the course of his employment did not cause or contribute to his heart attack on
February 21, 2007. If the evidence establishes that it is probable that the worker’s
employment activities, on February 21, 2007, did not cause or significantly contribute to
his heart attack on that date, the worker’s appeal must be denied. If the evidence is not
capable of establishing that it is probable that the employment activities did not cause or
contribute to the heart attack, the appeal must be allowed.
Page: 6
(d)
[25]
Decision No. 1987/14
No unusual physical exertion
Information about the worker’s activities on the day that he had his heart attack was
obtained from two individuals who were working with the worker that day. The information was
obtained by a WSIB investigator who spoke the individuals in July 2010.
[26]
Neither of the individuals indicated that the worker was involved in heavy or unusual
physical labour.
[27]
Witness RD stated that the worker had spent the morning preparing and covering the
floor with paper and taping. By the time of the worker’s collapse he had stopped that work and
several individuals were preparing the scaffold unit to start painting the ceiling. The worker was
standing on the first level of the scaffold that was being raised. The worker was described as
“resting” while another individual had gone to get more planks and bars to raise up the scaffold.
The worker suddenly leaned back against the wall, crouched over and collapsed on the scaffold
floor. RD stated, according to the investigator that he “was not aware of anything unusual that
had occurred to [the worker] on the worksite. No specific accident occurred. He had done
nothing physical nor had he over-exerted himself that morning.”
[28]
Witness SI stated that most of the morning, about two hours, had been spent covering the
floor and taping in order to start painting the ceilings of the home. The worker had done some
taping and “had done nothing unusual nor extremely physical that day”. At the time of the
worker’s collapse they had started to raise the scaffold unit. The worker was on the first level of
the scaffolding, laying down the planks. SI had gone to get more wooden planks and steel
scaffolding bars. He raised up a plank towards the worker who suddenly leaned back, crouched
over and collapsed.
[29]
The worker’s representative submits the following:
On the day in question, and immediately proceeding (sic) the heart attack, he was perched
on the first level of scaffolding, (approximately eight feet above ground), assisting with
erecting the multilevel scaffolding which would have required him to lift large, heavy,
wooden planks and steel scaffolding bars, pulling them from below (handed from a
co-worker) to assist in building the second level of scaffolding. The infarction occurred
immediately after this unusually physical exertion.
[30]
There is a lack of evidence to substantiate the submissions that the worker was
approximately eight feet above ground, or that the planks were large and heavy. It is also not
clear whether the worker himself was lifting the scaffolding bars or whether the scaffolding bars
being referred to were the lighter cross-pieces or the heavier end pieces.
[31]
According to SI who was working directly with the worker, the worker was standing on
the first layer of scaffolding and laying down planks. These planks were being lifted up to the
worker.
[32]
I accept that the worker would have had to climb the scaffolding which would have been
somewhat more difficult than climbing a ladder. The evidence however does not support that
laying down planks that were being handed up to him would have involved significant effort.
Nor does the evidence disclose to what extent the worker was involved in moving cross pieces or
end pieces of the scaffolding. Given the worker’s standing position on top of the first level of
scaffolding, it is a strong possibility in my view that, if lifting of the scaffolding pieces was
occurring prior to the worker’s collapse, the lifting was being performed by SI who was fetching
the scaffolding pieces. The worker may however have been assisting in the lift, if any lifting
Page: 7
Decision No. 1987/14
occurred prior to the attack, or the worker may have simply stabilized the scaffolding pieces
while they were being set in place.
[33]
While the precise involvement of the worker in erecting the scaffolding might be
somewhat unclear, it has not been established that the worker’s involvement was extensive.
Furthermore, what is clear is that RD stated that the worker had not done anything unusual, or
physical, nor had he over exerted himself that morning and SI stated that the worker had done
nothing unusual nor extremely physical that day and there are no witness statements from anyone
other than RD and SI.
(e)
[34]
[35]
Symptoms that preceded the heart attack
In addition to the lack of proof of significant physical effort on the day of the heart
attack, the evidence also indicates that the worker was exhibiting signs that he was experiencing
cardiac difficulties prior to the actual occurrence of the heart attack. This suggests that the heart
attack was not caused by the work being performed at the time of the worker’s collapse.
RD in his statement to the investigator states (in the words of the investigator):
For over a week before his collapse on June, 10, 2008, [the worker] had complained of
not feeling well but was not specific about his condition or problems. [RD] had suffered
from heart problems before and had stents inserted in to his heart. He had told [the
worker] to go see his doctor to get checked out but he refused saying he had not seen his
doctor for years.
[36]
[37]
Although the worker’s representative suggests that the worker may have been making
complaints about his arm and shoulder pains, RD’s reference to his own heart problems is
inconsistent with the representative’s suggestion.
Further evidence of prior symptoms suggestive of cardiac difficulties can be found in the
Ambulance Call Report that states in part as follows:
pt. hx of 1.5 hr of L arm pain prior to incident. Pt came in to work today (painter) c/o L
arm pain and at 0844 hrs collapsed in front of co-workers.
[38]
This report indicates that the worker had a history of 1.5 hours of left arm pain prior to
the heart attack and that the worker came in to work that day complaining of left arm pain prior
to the heart attack that occurred at 8:44.
[39]
Arm pain is, according to the Medical Discussion Paper a symptom of angina, unstable
angina, and heart attack.
[40]
This information that was obtained from the ambulance drivers on the very day of the
incident strongly suggests that the worker was experiencing early symptoms of his cardiac
difficulties prior to his engaging in his workplace activities and well before he collapsed.
Page: 8
DISPOSITION
[41]
The worker’s appeal is denied.
DATED: November 14, 2014
SIGNED: G. Dee
Decision No. 1987/14