Background: Evidence of carotid atherosclerosis can be detected in 3 to 5% of orthopantomogram (OPG) investigations. The clinical impact of these findings is unknown. We investigated the association of OPG findings of carotid atherosclerosis with the occurrence of future cardiovascular adverse events.
Patients and methods: We randomly selected 411 of 1268 participants with pre-existent cardiovascular disease from the prospective Inflammation in Carotid Arteries Risk for Arthrosclerosis Study (ICARAS) and assessed their OPGs for the presence of calcified atherosclerotic lesions or indirect signs of atherosclerosis, such as surgical clips or intravascular stents. The degree of carotid stenosis was measured by duplex ultrasound investigations. Patients were then followed for median 39 months (interquartile range 33 to 44 months) for the occurrence of major adverse cardiovascular events (MACE) including myocardial infarction, coronary revascularisation, stroke and death.
Results: We found no statistically significant association between the presence of carotid atherosclerosis detected on OPGs and the presence of a significant carotid stenosis (left carotid artery kappa=0.08; right carotid artery kappa=0.12), or the degree of carotid stenosis (P=0.20). Furthermore, the presence of OPG signs of carotid atherosclerosis was not statistically significant associated with future MACE (adjusted hazard ratio 0.92, 95% confidence interval 0.59 to 1.42; P=0.70).
Conclusions: Evidence of carotid plaque revealed by OPGs in patients with previously known cardiovascular disease is no useful prognostic marker for MACE. Detection of carotid atherosclerosis by OPGs in these patients therefore has no clinical consequence.