Coronary artery spasms and/or coronary air embolisms and contrast-induced encephalopathy during cryoablation of atrial fibrillation: a case report

ST-segment elevations in electrocardiogram associated with coronary air embolisms (CAEs) and/or myocardial ischaemia induced by coronary artery spasms (CASs) are rare complications during ablation of atrial fibrillation (AF); some patients develop severe conditions. Contrast-induced encephalopathy (CIE) is also a rare but severe complication associated with the use of iodinated contrast agents during various cardiovascular and neurovascular procedures. Its occurrence during ablation, particularly AF ablation, remains unreported.

We report a case in which CASs and/or CAEs associated with ST-segment elevation were observed, accompanied by worsening haemodynamics during AF cryoablation. Insertion of an intra-aortic balloon pump improved the haemodynamics. Following anaesthesia recovery, he developed verbal/expressive aphagia and left-sided hemiplegia. However, emergent cerebrovascular angiography revealed no cerebral artery occlusions or haemorrhage. Plain computed tomography (CT) showed diffuse cortical hyperdensity in the right temporal and both occipital lobes on Day 0, brain swelling by Day 2, and complete radiological recovery by Day 4. His symptoms, except for a slight grip drop of the left hand, improved by Day 4, leading to a diagnosis of CIE.

The key step of CIE may be attributed to a blood–brain barrier breakdown, which is influenced by multiple factors, including the direct chemotoxicity and hyperosmolarity of the contrast agent, ischaemic stroke (including cerebral vasoconstriction), and anaesthesia. Thus, physicians should consider the possibility of CIE when a patient exhibits neurological abnormalities during ablation, despite a lack of a CIE history with contrast-enhanced CT.