Isolated cardiac sarcoidosis masquerading as right ventricular outflow tract ventricular tachycardia
A 67-year-old man with coronary artery disease (CAD) and left anterior descending artery (LAD) stent presented with symptomatic monomorphic ventricular tachycardia (VT) at a rate of 190 bpm requiring cardioversion. ECG showed left bundle branch block pattern and inferior axis, suggestive of a right ventricular outflow tract (RVOT) focus rather than left ventricular scar due to LAD territory myocardial infarction (MI). Echocardiography showed normal wall motion. Angiography revealed a patent mid-LAD stent. Cardiac MRI with delayed postcontrast sequence revealed several regions of hyperenhancement abnormality within the basal portion of the interventricular septum. Increased metabolic activity on positron emission tomography confirmed active inflammatory sarcoidosis.Although VTs in patients with prior CAD are likely to be related to either scar or ischaemia, alternative diagnoses (eg, infiltrative disorders, RVOT-VT, arrhythmogenic right ventricular cardiomyopathy) should be considered in patients with an apparent right ventricular focus on ECG.
Atreya AR, Patel M, Sivalingam SK, Stoenescu ML. Isolated cardiac sarcoidosis masquerading as right ventricular outflow tract ventricular tachycardia. BMJ Case Rep. 2017 Jun 30;2017. pii: bcr-2017-220604.