Long-term application of vitamin K antagonists, more harm than good? The additional value of imaging

This editorial refers to ‘Patients using vitamin K antagonists show increased levels of coronary calcification: an observational study in low-risk atrial fibrillation patients’[†][1], by B. Weijs et al. , on page 2555 As Weijs et al .1 have described, most patients diagnosed with paroxysmal atrium fibrillation (AF) are currently treated by prescribing life-long use of vitamin K antagonists (VKAs) to prevent thrombo-embolic complications.2 By applying minimal invasive multislice computed tomography (MSCT) imaging, the authors found a possible adverse treatment effect in patients who were receiving VKAs for relatively longer, showing significant higher levels of calcium in their coronary arteries compared with patients with a shorter time on VKAs. This could have serious consequences for current clinical practice.2In contrast to many other patient populations with cardiovascular diseases, a subgroup of patients exist in which AF is diagnosed at a relatively young age. With this in mind, the long-term safety of the pharmaceutical treatment (in this case prevention) is therefore of great importance. Until recently, the effects of long-term treatment strategies on coronary vessel wall morphology, whose primary objective is not to be used to treat coronary artery disease (CAD), were impossible to study in humans other than by using invasive coronary imaging techniques such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT).3,4 These modalities can only be used in conjunction with invasive coronary angiography, which obviously will not be performed unless there is an indication for the presence of CAD. Furthermore, it would be necessary to image the complete coronary artery tree, which is not an easy task for catheter-based imaging modalities, and consequently a challenging … [1]: #fn-2