case_images: PMC11322077_01
case_images: Three-day-old bradycardia with a heart rate of 70-75 beats per minute. ECG interpretation: The rhythm was regular; one P wave was followed by a narrow QRS and the other P wave was buried in the T wave (red arrow) without a following QRS. The RR interval and interval between every two conducted P waves (red line) were fixed. However, the interval between the conducted P wave and non-conducted P wave (blue line) was shorter than the interval between the non-conducted P wave and conducted P wave (green line), which implied that the P wave was contracted early and was not followed by a QRS. Therefore, bigeminy PACs with block was diagnosed.
case_images: fped-12-1337135-g001.jpg
case_images: PMC11322077_01_fped-12-1337135-g001.jpg
case_images: F1
case_images: An ECG was performed and demonstrated bradycardia with a heart rate of 70-75 beats per minute (Figure 1).
case_images: PMC11322077_02
case_images: Seven-day-old bigeminy PACs with a heart rate of 150-170 beats per minute. ECG interpretation: The P wave of the sinus rhythm (blue arrow) was taller and broader than the P wave of the PACs (green arrow), which indicated the atrial contraction form atrial myocardium lower than SA node.
case_images: fped-12-1337135-g002.jpg
case_images: PMC11322077_02_fped-12-1337135-g002.jpg
case_images: F2
case_images: At 7 days, bigeminy PACs with a heart rate of 150-170 beats per minute was noted (Figure 2), which has correlated with the diagnosis of bigeminy PACs with block previously.
case_images: Twenty-three-day-old long RP and narrow QRS tachycardia with a heart rate of 200-250 beats per minute. ECG interpretation: The shorter and narrower P wave (green arrow) conducted form other atrial myocardium rather than SA node was still noted. Thus, atrial tachycardia was diagnosed.
case_images: fped-12-1337135-g003.jpg
case_images: PMC11322077_02_fped-12-1337135-g003.jpg
case_images: F3
case_images: In addition, a long RP and narrow QRS tachycardia (200-250 beats per minute) were found (Figure 3) at 23 days old.