Analysis Of PQRST Wave Patterns on Normal Heart using Student Experiment Cobra4 Electrocardiograph Dessy Amirudin (a*), Siti Nurul Khotimah (b)
a) Master Program in Physics Teaching, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia *dessyamirudin[at]gmail.com b) Faculty of mathematics and Natural Sciences, Bandung Institute of Technology Jalan Ganesha 10, Bandung 40132, Indonesia
This study aims to analyze the PQRST wave pattern of a normal heart including amplitude (A), time duration (t) and frequency (f) in each of the P, Q, R, S and T waves in the sitting and lying position. Furthermore, this study will create a module Operation of the student experiment cobra4 electrocardiograph instrument. The main system used was a set of student experiment electrocardiograph instruments. The study was conducted in two stages. These were recording the electrical activity of the heart at normal extremities and recording the electrical activity of the heart at the exchanged electrode lead. Each stage recorded two positions such as, sitting and lying position. In each position, the recording was implementing three different ways for the skin electrodes contact (i) direct contact, for example, it was not using gel and sensor gel, (ii) using gel and (iii) using gel and gel sensor. Before the activity was carried out, the operator installed a software measurement for data recording. The output of this recording was a complex PQRST heart wave pattern displayed on a PC. The data that has been displayed was then extracted using Ms.Excel and OriginPro 2016 32bit software. The conclusion from the results of this study is the position does not affect the results of hearts electrical activity recording. The results showed that sitting and lying position data were not much different. The example was taken from subject A. When the normal extremity in sitting position, the value of the amplitude interval (A), the duration of time (t) and frequency (f) of each wave were the P wave ((A): 19.00 mV - 51.76 mV, (t): 0.08 s - 10.11 s, and (f): 65.32 Hz - 92.37 Hz), Q wave ((A): 7.20 mV - 25.00 mV, (t): 0.03 s - 0.04 s, and (f): 65.48 Hz - 92.51 Hz), R wave ((A): 363.00 mV - 439.78 mV, (t): 0.06 s - 0.09 s, and (f): 65.59 Hz - 92.48 Hz), S wave ((A): 8.40 mV - 29.00 mV, (t): 0.03 s - 0.06 s, and (f): 66.45 Hz - 91.73 Hz), and T wave ((A): 58.63 mV - 162.61 mV, (t): 0.21 s - 0.24 s , and (f): 65.47 Hz - 92.63 Hz). Meanwhile, the value of the amplitude interval (A), time duration (t) and frequency (f) of each wave in subject A when lying position were P wave ((A): 29.57 mV - 59.71 mV, (t): 0.09 s - 0.14 s, and (f): 67.22 Hz - 83.71 Hz), Q wave ((A): 7.15 mV - 25.00 mV, (t): 0.03 s - 0.04 s, and (f): 66.41 Hz - 83.97 Hz), R waves ((A): 268.00 mV - 443.00 mV, (t): 0.07 s - 0.09 s and (f): 66.92 Hz - 83.49 Hz), S waves ((A): 10.40 mV - 23.00 mV, (t) : 0.03 s - 0.05 s, and (f): 67.08 Hz - 83.96 Hz), and T waves ((A): 68.64 mV -174.00 mV, (t): 0.21 s - 0.28 s, and (f): 67.15-83.70). The PQRST wave pattern displayed in the normal extremity leads for each position produced normal heart waves. However, if the electrode lead was exchanged, the PQRST heart wave pattern in each position was reversed. In the final stage of the study, it created a student experiment cobra4 electrocardiograph instrument module.
Keywords: amplitude (A), time duration (t), frequency (f) and student experiment cobra4 electrocardiograph