Great! We like #19 and #21.
Could we fill in the border of the heart in #19 so it does not look like there is a big empty space in the lower left of the heart? Also, can the .com be moved to the bottom somehow without interrupting the underline? Lastly, the ECG strip within the heart is not academically correct. There needs to be a "P wave", "QRS complex" and "T wave". You can visit
http://www.openecg.net/ and look at the logo in the upper left. Thanks!