Abstract: A cardiac rhythm management system provides for the trending of a third heart sound (S3) index. The S3 index is a ratio, or an estimate of the ratio, of the number of S3 beats to the number of all heart beats, where the S3 beats are each a heart beat during which an occurrence of S3 is detected. An implantable sensor such as an accelerometer or a microphone senses an acoustic signal indicative heart sounds including S3. An S3 detector detects occurrences of S3 from the acoustic signal. A heart sound processing system trends the S3 index on a periodic basis to allow continuous monitoring of the S3 activity level, which is indicative of conditions related to heart failure.

Abstract: The output state of a pulse wave optimum to the user and applied to the head of the user is automatically set while improving the wearability of the electrodes, and different output states of pulse waves can be simultaneously applied to a large number of users. A pulse wave of predetermined pattern is given to the skin near an ear of the user and/or of the back of a hand of the user to directly stimulate and activate the brain. This stimulation is significantly effective especially for colorblindness. By systematizing such a revolutionary therapy, pulse waves of different patterns can be applied to a large number of patients (users), enabling a quick, effective therapy.