Electropharmacological testing by transoesophageal atrial pacing in inducible supraventricular tachyarrhythmias

Sixty-eight patients with disabling episodes of inducible supraventricular tachyarrhythmia were tested electropharmaco-logically by transoesophageal atrial pacing. Using this technique we induced clinical arrhythmia in 67 (98.5%); 26 (38.8%) had a reciprocating tachycardia due to A V node reentry and 41 (61.2%) a by-pass tract. In the latter we induced a reciprocating tachycardia in 12 (29.3%), atrial fibrillation in 25 (36.5%) and both in 14 (34.2%). We then performed an anti-arrhythmic drug test and a transoesophageal reevaluation either after acute intravenous drug administration or during oral steady state. Altogether we tested 111 drugs or a combination of drugs before the results were considered positive; all patients tolerated the procedure well and were discharged with the drug or combination of drugs judged effective. At follow-up of 16.6±8.5 months, 42 patients (62.7%) were symptom-free, 17 (25.3%) had minor and non-disabling relapses, six (9%) stopped the drug because of inefficacy (1–1.5%) or side effects (5–7.5%); two (3%) dropped out. We conclude that electropharmacological testing with transoesophageal pacing constitutes a very good approach for inducible supraventricular tachyarrhythmias: it permits selection of optimal long-term anti-arrhythmic treatment and is well tolerated, only slightly invasive and without adverse effects.