Non ST Elevation MI with Non- significant Coronary Artery Disease as a Symptom of Occult or New Malignancy

Background: Malignancy is a known risk factor for venous thromboembolism; however, the association with arterial thromboembolic events remains unclear.

Objective: We aimed to examine the association between Non-ST elevation MI with non- significant Coronary artery Disease, and the presence of new or occult malignancy.

Methods: Observational, cohort, single center study, performed between 2010-2015. Adult patients with NSTEMI, who underwent coronary angiography and had no significant coronary lesion, were included. Using Propensity Score Matching, we created a 2:1 matched control group of adults with NSTEMI, and significant CAD. Risk factors for new or occult malignancy were assessed using multivariate backward stepwise logistic regression analysis. The primary outcome was new or occult malignancy, defined as any malignancy diagnosed in the 3 months prior and 6 months following the MI.

Results: During study period, at our center, 174 patients with MI with non-obstructive coronary arteries were identified. The matched control group included 348 patients. There was no significant difference in both groups’ demographics, past medical history or clinical presentation. The incidence of new or occult malignancy in the study group was significantly higher (7/174, 4% VS 3/348, 0.9%; P value 0.019). NSTEMI with non- significant CAD was an independent risk factor for occult malignancy (OR 4.6 ;95% CI: 1.1-18.7). Other risk factors were active smoking (OR 11.2; 95% CI 2.5-49.1) and age (OR 1.1; 95% CI 1.03-1.17).

Conclusions: Non ST elevation MI with non- significant Coronary artery Disease may be the presenting or early marker of malignancy and may warrant further investigation.