Radiofrequency catheter ablation for inappropriate sinus tachycardia in a patient with systemic lupus erythematosus: a case report

BACKGROUND: Systemic lupus erythematosus (SLE) is known to cause inappropriate sinus tachycardia (IST). However, there is limited evidence available with regard to the treatment of IST in this setting. In this article, we report a case of drug refractory IST in a patient with SLE treated with radiofrequency catheter ablation (RFCA) using a non-contact mapping system. CASE SUMMARY: A 33-year-old woman had been diagnosed with SLE in 2001. She presented with complaints of persistent palpitations for 1 month and persistent sinus tachycardia. She underwent RFCA using a non-contact mapping system for drug refractory IST. The voltage and activation maps did not show obvious differences in the earliest activation site at heart rates (HRs) 90–150 b.p.m. In contrast, the areas of breakout sites were clearly distinguished between those from the normal P-wave zones at HR <140 b.p.m. and those from higher rate sites at HR >140 b.p.m. Radiofrequency catheter ablation was performed in those areas as the target for ablation. Thereafter, the symptoms steadily disappeared and the maximum HR—using 24-h Holter monitoring—decreased from 156 to 120 b.p.m. DISCUSSION: Radiofrequency catheter ablation using a non-contact mapping system was applied to the treatment of drug refractory IST in a patient with SLE. Of note, IST in such patients may be left untreated. This approach may be considered as a first-line therapy option for drug refractory IST in patients with SLE.