Proteomic Comparison of Acute Myocardial Infarction and Stress Cardiomyopathy in Women

Background: Stress cardiomyopathy (SCM) is a unique form of LV dysfunction that more often occurs in women. Patients with SCM have a higher Troponin I/B-type natriuretic peptide ratio than AMI, but little is known about other circulating proteins. The goals of this study were to compare plasma proteins in SCM and AMI to learn about the pathophysiology of SCM and also to identify putative biomarkers of SCM. Methods: Blood was drawn in normal controls (n=6), women with AMI (n=12) or women with acute SCM (n=15). Two-week follow up samples were available in AMI (n=4) and SCM patients (n=11). Relative concentrations of 1310 serum proteins were measured in each of the 48 samples using the SOMAscan aptamer based assay. Women with AMI tended to be younger (57.87 ± 16.0 vs. 65.08 ± 9.11 years, p=0.12) and had a higher peak troponin I (AMI 32.03 ± 29.46 vs. SCM 2.68 ± 2.6 ng/mL, p=0.02). No differentially expressed proteins were detected (absolute log2 fold change>1; q<0.05) between AMI and SCM in the acute or recovery phase. In the normal vs. AMI comparison there was differential expression of 35 proteins. In the normal vs. SCM comparison there were 45 proteins with differential expression. Pathway analysis demonstrated activation of complement, coagulation, and inflammation in both AMI and SCM. Conclusions: The acute phase of SCM is characterized by a severe inflammatory response similar to AMI. Despite recovery of LV function in SCM at two weeks, differences in circulating proteins remain in comparison to normal controls. 48 serum samples total measured. Non fasting venous blood, collected in SST tubes, within 24 hours of hospital admission. Normal controls (n=6), Acute myocardial infarction (AMI) (n=12), acute stress cardiomyopathy (SCM)(n=15), Follow up AMI (n=4), Follow up SCM (n=11)