PMC5029147_01
ECG monitoring findings in patient 1. (A) On admission: frequent polymorphic ventricular ectopic beats with couplets and triplets and QTc prolongation (520 ms). (B,C) Recurrent episodes of torsades de pointes, with degeneration to ventricular fibrillation (C). Red vertical lines show QT interval.
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F1
The ECG on admission showed T-wave inversion in peripheral and precordial left leads and QTc prolongation (520 ms), as well as frequent polymorphic ventricular ectopic beats (Figure 1A). Although the immediate postoperative period was uneventful, 3 days later, he suddenly presented with two episodes of TdP, the second one rapidly degenerating to VF (Figures 1B,C) that was reversed by DC-shock. Moreover, RA treatment maintained the disease in remission, and QTc stably remained near-normal/slightly prolonged (450-460 ms) (Figure S1 in Supplementary Material).
PMC5029147_02
ECG findings in patient 2. (A,B) Atrioventricular dissociation with low-rate PM-induced ventricular beats (45 bpm), alternating with narrow beats from a junctional escape revealing QTc prolongation (550 ms). Red vertical lines in lead II show QT interval. (C) Torsades de pointes episode at ECG monitoring.
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F2
Notably, at this time also QTc was shortened to ~500 ms (Figure S2 in Supplementary Material).
PMC5029147_03
ECG findings in patient 2. (A,B) Atrioventricular dissociation with low-rate PM-induced ventricular beats (45 bpm), alternating with narrow beats from a junctional escape revealing QTc prolongation (550 ms). Red vertical lines in lead II show QT interval. (C) Torsades de pointes episode at ECG monitoring.
fcvm-03-00031-g002.jpg
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F2
Notably, at this time also QTc was shortened to ~500 ms (Figure S2 in Supplementary Material).
ECG findings on patient 3 on admission. (A,B) T-wave alternans with marked QTc prolongation, ranging from 690 to 870 ms. Red arrows, long and short, indicate T-wave changes. Red vertical lines in lead V5 show QT interval, while red asterisks indicate where QTc is calculated (*690 ms; **870 ms).
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F3
On admission, ECG demonstrated sinus rhythm with sporadic ventricular ectopic beats, diffuse T-wave inversion with T-wave alternans, and marked QTc prolongation (690-870 ms; Figure 3).