A medical device system and method that includes sensing a heart sound signal from a first external sensor, determining whether a pulmonary hypertension signature is detected in response to the sensed heart sound signal, sensing a lung sound signal from a second external sensor, determining whether a heart failure signature is detected in response to the sensed lung sound signal, and determining therapy parameters in response to determining whether a pulmonary hypertension signature is detected and determining whether a heart failure signature is detected.