Willem Einthoven found the beat and built a machine that could measure the electrical current a heart creates. It weighed 600 pounds An electrocardiogram — called informally an ECG or EKG — measures the small electric waves that a human heart creates. It’s been doing it for more than a century. And as heart disease remains a leading cause of death today, it continues to be one of the most commonly used tests in modern medicine Birth of the ECG Dutch scientist Willem Einthoven, who won a Nobel Prize for crafting the medical tech masterwork, was [...]