Catheter ablation of Wolff-Parkinson-White syndrome in conjoined thoracopagus twins.

We previously reported unusual electrocardiograms (ECGs) recorded from conjoined thoracopagus twins with a cardiac connection at the atrial level, and Wolff-Parkinson-White (WPW) syndrome in Twin B. 1 Correa R. Shivapour J. Johnikin M.J. Walsh E.P. WPW in conjoined thoracopagus twins. Heart Rhythm. 2014; 11: 336-337 Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar Tachycardia began in utero and was managed adequately with transplacental digoxin until elective C-section was performed at 36 weeks’ gestation. Postnatal evaluation demonstrated cardiac fusion of the lateral atrial walls and structural heart defects in both sisters (Twin A: tetralogy of Fallot; Twin B: dextrocardia, double-outlet right ventricle with a straddling tricuspid valve and multiple ventricular septal defects). On ECG, both twins had synchronous heart rates with two separate QRS (Twin A: narrow QRS with PR interval 170 ms; Twin B: manifest preexcitation). Since day 1 of life, whenever orthodromic reciprocating tachycardia (ORT) occurred in Twin B, Twin A would respond with variable atrioventricular (AV) conduction (often 2:1, but sometimes accelerating to a 1:1 pattern).