APPENDIX A

 

MMCC CASE LAW

 

 

GENERAL COMMUNITY AND COHORT SURVEILLANCE RULES

 

Final Classification Rules

 

1.      When the death certificate is the only available document, and the ICD code is compatible with CHD (410-414, 427.5, 429.2, 799) then final ARIC classification of cause of death is usually “Possible CHD,” unless there is (I) a demonstrable coding error, or (II) an explicit non-CHD probable cause of death (such as malignant hypertension with renal failure). Analogously, for other ICD codes the classification of cause of death is usually “Non-CHD”.

 

2.      The classification “Diagnosis Unclassifiable” will be reserved for cases not meeting ARIC criteria for CHD diagnosis, but in whom a specific non-atherosclerotic or non-cardiac atherosclerotic process cannot be identified.

 

3.      In the case of conflicting information, the more inclusive cause of death (e.g., Definite CHD rather that Definite MI) is preferred.

 

4.      Stroke qualifies as a “yes” answer to “a non-atherosclerotic or non-cardiac atherosclerotic process,” if judged to be the probably cause of death.

 

5.       If the decedent was debilitated from a potentially lethal non-atherosclerotic or non-cardiac process and had a related downhill course, with no symptomatic evidence of a recent coronary event, the death is classified a non-CHD.

 

6.      In cases of “Definite” or “Probable MI,” treated or aborted with TPA or similar clot-dissolving therapy, in which the patient dies of a direct complication or adverse effect of this therapy (i.e., hemorrhage), a final death classification of “Definite fatal CHD” should usually be assigned.

 

7.      If a patient having an elective CABG dies as a complication of surgery, a final death classification of “Definite fatal CHD” should usually be assigned.

 

8.      Generally, “hypertensive heart disease” will not be considered a “nonatherosclerotic cause of death”.

 

Chronology

 

9.      Death is assumed to have occurred at the time the patient stops breathing on his/her own and does not recover.

 

10.  Symptoms are assumed to begin when the patient changes his/her activity. If symptoms come and go, the onset of symptoms is the time when they crescendo, leading to death.

 

11.  In cases where timing of symptoms or death is unknown, the best estimate of the chronology is to be made.

 

12.  Symptoms of CHD leading to a hospital admission for CHD are usually considered to be related to a subsequent death from CHD, which occurs either before discharge or within 28 days of admission, which ever occurs first. Deaths of doubtful chronology admitted for the investigation or treatment of CHD are classified as deaths occurring in > 24 hours if admitted for at least 24 hours.

 

13.  Unknown chronology of death is an institutionalized patient is usually considered to be < 24 hours.

 

Evidence

 

14.  The relative credibility of conflicting witnesses is established from all the available evidence, i.e., there is no fixed hierarchy of credibility (such as physician overriding a lay informant). However, as a general rule:

 

a.      A knowledgeable physician takes priority for medical history.

b.      A witness takes priority for events around death and timing of death.

 

15.  A clinical history of ASHD or CHD counts as evidence of previous manifestations of CHD. If the event under consideration is the first manifestation of CHD, it does not quality as a “history” of CHD.

 

16.  A history of CABG or coronary angioplasty at any time prior to death is equivalent to a positive history of CHD.

 

17.  For community surveillance events, a coroner’s listing of causes of death (e.g. ASCVD) is interpreted only as findings at death and is not sufficient evidence, by itself, of past history. Other non-autopsy information, however, such as reported previous MI, may suffice as evidence of past history.

 

18.  Autopsy evidence of old MI or other chronic CHD may not be used as evidence of a history of CHD in community surveillance events.