This book provides quantitative validated rules for evaluating serial ECG change. Just as the original Minnesota Code uses specified measurement rules to reduce coding variability and a systematic code to indicate these measurements, serial comparison uses a set of measurement rules and a systematic code to document categories of ECG pattern changes. These criteria classify ECG change as 'No change', significant increase or significant decrease in specific waveform characteristics. Unlike clinical ECG comparison this procedure provides change criteria independent of clinical judgement that have also been validated for their prognostic significance for cardiac endpoints. Updated to reflect changes in understanding over the last 20 years, this title provides the benchmark for coding in electrocardiographic applications.