Syncope due to Recurrent Ventricular Tachycardias after TAVI with Unexpected Diagnosis in Cardiac Computed Tomography: a case report

Delayed coronary obstruction (DCO) is a rare but potentially life-threatening complication after transcatheter aortic valve implantation (TAVI) mostly affecting the left main coronary artery (LMCA) and often caused by prosthesis endothelialization or thrombus formations. Herein, we report an unusual case of a delayed LMCA-obstruction caused by a calcium nodule, which was diagnosed 4 months after TAVI due to recurrent ventricular tachycardia (VT) episodes. A 73-year-old patient was readmitted to an external hospital with syncope three months after TAVI. Fast VT could be induced in electrophysiological examination, why the patient received a 2-chamber implantable cardioverter defibrillator (ICD). However, after one month the patient was readmitted to our department with another syncope. ICD records revealed multiple fast VT episodes (200-220bpm). In addition, the patient reported new-onset exertional dyspnea (NYHA stage III) and elevated high-sensitive cardiac troponin of 115ng/L. Due to symptoms and laboratory markers indicating potential myocardial ischemia, a cardiac computed tomography angiography (CCTA) was performed. CCTA revealed obstruction of the left main coronary artery likely caused by calcium shift during TAVI. After CCTA-guided percutaneous coronary intervention, patient´s course remained uneventful. The present case report highlights the role of CCTA as a powerful non-invasive diagnostic tool in complex settings after TAVI. DCO as a procedural complication can occur after TAVI and manifest with various symptoms, including new-onset or recurrent VTs, like in the present case. CCTA provided accurate assessment of the implanted prosthesis and detection of DCO, thus guiding the subsequent PCI.