Barrabes et al identified risk factors associated with in-hospital mortality following a first myocardial infarction with non-ST segment elevation. This can help identify patients who may benefit from more aggressive management. The authors are from Hospital Universitari Vall d'Hebron in Barcelona, Spain.
Selection criteria: Patients with a (1) first acute myocardial infarction, (2) without ST segment elevation >= 0.1 mV in leads other than aVR or V1, and (3) without left bundle branch block.
Parameters:
(1) Killip class
(2) ST segment elevation in lead aVR
(3) systolic blood pressure (mean 143-149 mm Hg in the 3 subgroups)
(4) peripheral artery disease
(5) age (mean age in the 3 subgroups in the study ranged from 60 to 66 years of age)
Risk factors for in-hospital mortality (from Table 4, page 817):
(1) Killip Class >= 2 (odds ratio 6.11)
(2) ST segment elevation in lead aVR >= 0.05 mV (odds ratio 4.24 for 0.05 to 0.099 mV and 6.61 for >= 0.1 mV)
(3) systolic hypotension (odds ratio increases 1.16 for each 10 mm Hg decrease in systolic blood pressure)
(4) presence of peripheral artery disease (odds ratio 2.76)
(5) increasing age (odds ratio increases 1.04 for each 1 year increment)
where:
• Killip Class 2 indicates heart failure, Class 3 severe heart failure and Class 4 cardiogenic shock.
• The presence of left main or 3 vessel coronary artery disease was seen in 22% of patients without aVR segment elevation, but 43% of those with 0.05-0.099 mV and 66% of those with >= 0.1 mV elevation in ST segment of lead aVR.
The mortality in the subgroup with aVR ST segment elevation >= 0.1 mV was 19.4%.
A patient with ST segment elevation in lead aVR will often have more extensive coronary artery disease and so should be a candidate for early invasive diagnosis and management.
