Source: Mervyn S. Gotsman, and Stephen Adler, International Social Security and Workers Compensation Journal, Volume 1 Issue 1, 2009
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Workers compensation systems compensate for work accidents and occupational diseases. Multi-causal diseases, such as heart disease, are not accidents and are not occupational diseases. They are an ordinary part of life, and heart attacks, for example, may occur without a precipitating event. However, coronary heart disease may be aggravated by unusual physical exertion or mental stress, resulting in a myocardial infarct (heart attack). If such strain or stress occurs at work, it is often compensated for by the workers compensation system. This paper asks whether the legal theories that are used to determine if a heart attack should be recognised as a work accident are consistent with modern medical knowledge on the subject. To answer this question, we must first examine the medical theory relating to the effect of an event at work on a latent illness, such as pre-existing heart disease, which must be present to produce a heart attack.
We describe events at work as 'triggers' of acute myocardial infarction. However, most of these triggers are not connected to the workplace. Triggers occasionally occur during an unusual, sudden and acute emotional event, such as stress or unusual physical effort at work, which, therefore, are work-related. This work-related event results in ruptured plaque in a diseased coronary artery. Intimal (the inner layer of the artery) disruption initiates a thromboembolic clot of the coronary artery involved. Thrombus forms, obstructs the artery, coronary fow is impeded, and the distal myocardium undergoes necrosis and infarcts (an acute myocardial infarction or heart attack). Thus, the sudden acute emotional event or physical effort at work has caused a heart attack, which should be compensated by the workers compensation system.
The medical and legal basis for recognising the relationship between the trigger and the heart attack are not precise. We suggest that an unusual acute stressor, or trigger, which occurs in the workplace, should be the basis for recognising the infarct as a work accident. In Israel, when it has been determined that a work-related trigger event contributed to the occurrence of a heart attack, the attack is recognised as a work accident.
This paper describes the importance of risk factors which can cause a heart attack, the experimental, pathological, and clinical evidence of plaque rupture as a cause of heart attacks, clinical examples, and legal theories for recognising a heart attack as a work accident, with particular reference to Israeli and American sources.