Predictive Instrument for Coronary Care

 

Parameters:

(1) Medical History

(1a) history of previous myocardial infarction

(1b) history of angina pectoris

(2) Physical Examination

(2a) patient reports chest pain as chief complaint

(2b) chest pain located in lower or midsternum

(2c) presence of dyspnea

(3) Electrocardiogram (ECG)

(3a) ST segments dichotomized as normal or abnormal

(3b) ST waves if abnormal (1) depressed 1 mm or more; (2) elevated 1 mm or more

(3c) T waves dichotomized as normal or abnormal

(3d) T-waves if abnormal (1) inverted 1 mm or more, or (2) elevated more than 25% of the R wave

Parameter	Coefficient
intercept	-17.13
history of previous myocardial infarction	1.56
history of angina pectoris	0.86
patient reports chest pain as chief complaint	0.96
presence of dyspnea	1.10
chest pain located in lower or midsternum	1.58
ST segments dichotomized as normal or abnormal	1.68
ST waves if abnormal (1) depressed 1 mm or more; (2) elevated 1 mm or more	1.41
T waves dichotomized as normal or abnormal	0.45
T-waves if abnormal (1) inverted 1 mm or more, or (2) elevated more than 25% of the R wave	1.61

 

parameter value:

• 1 if present

• 2 if absent

 

probability of acute ischemic heart disease =

= 1 / (1 + EXP (((intercept coefficient) + SUM ((coefficient) * (variable value)))))

 

Interpretation:

• maximum probability is 100%

• minimum probability is 0.50 %

• initial evaluation showed a diagnostic accuracy of 91%