Hình 3,12 R biên độ theo độ tuổi trong V1 dẫn, mỗi đường cong tương ứng với mức phần trăm chỉ (• = trung bình). R sóng biên độ giảm V1 nổi bật sau đó dần dần từ sơ sinh đến tuổi vị thành niên. Một làn sóng R ở V1 16,5 mm có thể được bình thường ở trẻ sơ sinh đủ tháng. | CHAPTER R amplitude by age in lead V1 Age days Age months Age years R amplitude by age in lead V1 each curve corresponding to the Indicated percentile level . mean . R waves amplitude in V1 declines strikingly then gradually from birth to adolescence. An R wave in V1 of mm can be normal in term newborns. Age Days Months Years b 0-1 1-3 3-7 7-30 1-3 3-6 6-72 1-3 3-6 6-9 9-73 bh 13-18 95 . Mean r. SD 2 933 5 5 9 109 12 8 95 100 113 91 99 113 100 99 280 510 32 CHAPTER R amplitude by age in lead V2 Age days Age months Age years R amplitude by age In lead V2 each curve corresponding to the Indicated perceintile level . mean . R waves in V2 are most prominent. The amplitude can be high up to mm after birth. It decreases strikingly with increasing age throughout early childhood to adolescence. 3it 3i3 Days Months Years 0-1 1-3 3-7 7-30 1-3 3-6 6-72 1-3 3-6 6-9 9-73 73-78 95 Mean .72 1 SD 033 52 0-42 0 40 . 500 3 83 p 5 CN57 0 43 t N m 109 128 N 95 100 113 91 67 16 113 C7 96 _N 289 . 510 33 CHAPTER R amplitude by age in lead V4 Age days Age months Age years R amplitude by age In lead V4 each curve corresponding to the Indicated percentile level mean . The R wave amplitude in V4 increases strikingly after age 1-3 months reaching a plateau by age 6-12 months and starts to decline by age 9-13 years and thereafter. Age . Months Years 0-1 1-3 3-7 7-30 1-3 3-6 6-72 1-3 3-6 6-9 9-73 73-78 95 Mean T21 2858 2J0 SD
