PMC9386155_01
(A) Resting ECG in the proband, showing sinus rhythm, QTc prolongation (567 msec) and deep T wave inversion in anterior leads. (B) Resting ECG in the sister of the proband, showing sinus rhythm, normal QTc (442 msec) and T wave inversion in anterior leads. (C) Resting ECG in the father of the proband during mild hypokalemia (K+ 3.3 mEq/L), showing sinus rhythm, prolongation of QTc (614 msec) and biphasic T-waves. (D) Resting ECG in the father of the proband during normokalaemia (K+ 4.1 mEq/L), showing sinus rhythm, prolongation of QTc (550 msec), and biphasic T-waves (pseudo-U waves).
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F1
ECG showed sinus rhythm, QTc interval 442 ms and T wave inversion in the anterior leads V1-V4 (Figure 1B). The analysis of the clinical documentation showed that he had a transient prolongation of the QTc interval (614 ms) during mild hypokalemia (K+ 3.3 mEq/L), Figure 1C. We revised his previous ECGs that indicated a wide range of T wave alternans, biphasic T waves (often described as U waves) and a long T wave terminal slope (Figure 1D).
(A) Echocardiographic parasternal short-axis view in the proband: diastole (upper panel) and systole (bottom panel). Trabecular/compacted end-systolic wall thickness ratio >2 (positive Jenni criteria for LVNC). (B) Echocardiographic parasternal short-axis view in the sister of the proband: diastole (upper panel) and systole (bottom panel). Trabecular/compacted end-systolic wall thickness ratio >2 (positive Jenni criteria for LVNC).
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F2
Except for the duration, the QTc and ECG of the girl and her brother looked very similar, and an echocardiogram proved normal biventricular function and criteria for apical LVNC (Figure 2B). ECG-Holter monitoring confirmed standard sinus rhythm, average QTc values, and no episodes of bradycardia or hyperkinetic arrhythmias.
Cardiac Magnetic Resonance end-diastolic 2-chamber (A) and 4-chamber (B) SSFP cine view showing an increased trabecular/compacted wall thickness ratio.
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F3
Cardiac magnetic resonance end-diastolic 2-chamber and 4-chamber SSFP cine view showed an increased trabecular/compacted wall thickness ratio, confirming the echocardiographic finding (Figure 3).
Proband's loop Recorder trace during cardiac arrest, showing QTc prolongation, ectopic ventricular beats and ventricular fibrillation.
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F4
The analysis of the loop recorder revealed an episode of ventricular fibrillation that lasted about 1.40 min and was preceded by a brief phase of ventricular bigeminy (Figure 4).
PMC9386155_02
(A) Resting ECG in the proband, showing sinus rhythm, QTc prolongation (567 msec) and deep T wave inversion in anterior leads. (B) Resting ECG in the sister of the proband, showing sinus rhythm, normal QTc (442 msec) and T wave inversion in anterior leads. (C) Resting ECG in the father of the proband during mild hypokalemia (K+ 3.3 mEq/L), showing sinus rhythm, prolongation of QTc (614 msec) and biphasic T-waves. (D) Resting ECG in the father of the proband during normokalaemia (K+ 4.1 mEq/L), showing sinus rhythm, prolongation of QTc (550 msec), and biphasic T-waves (pseudo-U waves).
fped-10-970240-g0001.jpg
PMC9386155_02_fped-10-970240-g0001.jpg
F1
ECG showed sinus rhythm, QTc interval 442 ms and T wave inversion in the anterior leads V1-V4 (Figure 1B). The analysis of the clinical documentation showed that he had a transient prolongation of the QTc interval (614 ms) during mild hypokalemia (K+ 3.3 mEq/L), Figure 1C. We revised his previous ECGs that indicated a wide range of T wave alternans, biphasic T waves (often described as U waves) and a long T wave terminal slope (Figure 1D).
(A) Echocardiographic parasternal short-axis view in the proband: diastole (upper panel) and systole (bottom panel). Trabecular/compacted end-systolic wall thickness ratio >2 (positive Jenni criteria for LVNC). (B) Echocardiographic parasternal short-axis view in the sister of the proband: diastole (upper panel) and systole (bottom panel). Trabecular/compacted end-systolic wall thickness ratio >2 (positive Jenni criteria for LVNC).
fped-10-970240-g0002.jpg
PMC9386155_02_fped-10-970240-g0002.jpg
F2
Except for the duration, the QTc and ECG of the girl and her brother looked very similar, and an echocardiogram proved normal biventricular function and criteria for apical LVNC (Figure 2B). ECG-Holter monitoring confirmed standard sinus rhythm, average QTc values, and no episodes of bradycardia or hyperkinetic arrhythmias.