This document discusses, among other things, systems and methods to determine a blood pressure measurement of a subject, such as a systolic blood pressure of a subject, a diastolic blood pressure of the subject, or both, using received heart sound information and plethysmography information of the subject. The system can include a signal receiver circuit configured to receive the heart sound information and plethysmography information of the subject, and an assessment circuit configured to determine the systolic and diastolic blood pressure of the subject using the received heart sound information and the plethysmography information of the subject.