Ключевые слова: background, beat, black, blackboard, bright, cardiac, care, chalk, chalkboard, chart, coaching, concept, diagnosis, doctor, ecg, electrocardiogram, fingers, frame, frequency, graph, graphic, hand, health, healthcare, healthy, heart, heartbeat, help, hospital, idea, illustration, life, line, man, medical, medicine, monitoring, physician, practitioner, prevention, professional, pulse, rate, rhythm, sign, text, white, wood,