1. A computer-implemented method of detecting an impending decompensation of heart failure in a patient, the method comprising: receiving, at a computer, transthoracic impedance data measured by a cardiac rhythm management device implanted in the patient, wherein the cardiac rhythm management device measures the transthoracic impedance data while the patient is standing on a scale; obtaining, at the computer, a weight measurement, the weight measurement indicating a weight of the patient, the computer obtaining the weight measurement from the scale, the scale measuring the weight of the patient while the patient is standing on the scale; and receiving, at the computer, answers provided by the patient to one or more questions posed to the patient; detecting, at the computer, impending decompensation of acute heart failure, based at least in part upon the weight measurement, the answers and the transthoracic impedance data received from the cardiac rhythm management device, wherein the act of detecting impending decompensation of heart failure comprises generating a score based at least in part upon the answers provided by the patient or the weight measurement and comparing the score to a threshold.