Our objectives are to describe the contents of cardiovascular surgical operative notes and to develop and test a standards-based structured electronic operative note that might be used for secondary purposes. Operative notes were selected for patients who underwent primary, isolated coronary artery bypass grafting (n = 33); aortic valve replacement (n = 33); reoperative coronary artery bypass grafting (n = 11); or aortic valve replacement (n = 11). The content was qualitatively assessed and categorized into 3 sections, ie, technical/procedural, anatomic/physiologic description, and judgment/opinion. An electronic operative note was developed using a standards-based approach to categorize the type of operation. Average length +/- SD of the operative note was 495 +/- 186 words (range 243 to 1,267 words). The procedural category made up a mean proportion of 73% +/- 12% (range 32% to 95%). The descriptive category was the second largest category in the operative note; mean percentage 22% +/- 8% (range 5% to 43%). The dictation of the judgment portion made up 6% +/- 6% (range 0% to 25%) of the operative note. In the pilot electronic note system, 5 surgeons entered 23 procedures performed on 18 patients (14% of eligible patients). Seventeen (74%) procedures entered by surgeons were in complete agreement with the data for the Society of Thoracic Surgeons database collected by professional abstractors. Freeform dictation of cardiovascular notes varied by individual surgeon style and case complexity. Up to 25% of the operative note was dedicated to judgment/opinion, which would be difficult to recreate in a structured data-entry format. An electronic system for entering procedural details can improve efficiency for secondary purposes of data collection but must be carefully implemented to avoid loss of important information.