Heart failure decompensation prediction based on cardiac rhythm

Abstract

Systems and methods of detecting an impending cardiac decompensation of a patient measure an electrocardiogram signal of the patient. An incidence of cardiac arrhythmias is determined from the electrocardiogram signal. A risk of impending decompensation is determined in response to the incidence of cardiac arrhythmias. In many embodiments, the impending decompensation can be detected early enough to avoid, or at least delay, the impending decompensation, such that patient trauma and/or expensive ICU care can be avoided. Although embodiments make specific reference to monitoring electrocardiogram and other physiological signals with an adherent patch, the system methods and devices are applicable to many applications in which physiological monitoring is used, for example wireless physiological monitoring with implanted sensors for extended periods.

1 . A method of detecting an impending cardiac decompensation of a patient, the method comprising:
 measuring an electrocardiogram signal of the patient;   determining an incidence of cardiac arrhythmias from the electrocardiogram signal;   measuring a bioimpedance of the patient;   determining from the measured bioimpedance a measure of a respiration of the patient; and   determining a risk of impending decompensation in response to a combination of the measured respiration and the incidence of cardiac arrhythmias.   
     
     
         2 . The method of  claim 1  wherein the electrocardiogram signal is measured for at least one week and the risk of impending decompensation is determined in response to the incidence of cardiac arrhythmias measured for the at least one week. 
     
     
         3 . The method of  claim 1  wherein the incidence of cardiac arrhythmias is compared to an earlier baseline incidence of cardiac arrhythmias for the patient to determine the risk of impending decompensation. 
     
     
         4 . The method of  claim 1  wherein the incidence of cardiac arrhythmias is compared to an earlier baseline incidence of cardiac arrhythmias for a patient population to determine the risk of impending decompensation. 
     
     
         5 . The method of  claim 1  wherein the electrocardiogram signal comprises at least one of a derived signal, a time averaged signal, a filtered signal or a raw signal. 
     
     
         6 . The method of  claim 1  wherein the measured respiration and the incidence of cardiac arrhythmias are combined with at least one of a heart rate, a heart rate variability, an activity or a tissue hydration measurement of the patient to determine the risk of impending decompensation. 
     
     
         7 . The method of  claim 6  wherein at least one of a weighted combination, a tiered combination or a logic gated combination, a time weighted combination or a rate of change is used to combine the measured respiration and the incidence of cardiac arrhythmias with the at least one of the heart rate, the heart rate variability, the activity or the tissue hydration of the patient. 
     
     
         8 . The method of  claim 1  wherein the incidence of cardiac arrhythmias is determined with an atrial arrhythmia comprising at least one of a bradycardia, an atrial fibrillation, an atrial tachycardia, or an atrial flutter. 
     
     
         9 . The method of  claim 1  wherein the incidence of cardiac arrhythmias is determined with a ventricular arrhythmia comprising at least one of a bradycardia, a sustained ventricular tachycardia, a non-sustained ventricular tachycardia or a premature ventricular contraction. 
     
     
         10 . The method of  claim 1  wherein the electrocardiogram signal is measured with an adherent patch comprising electrodes, the patch continuously adhered to the patient for at least one week. 
     
     
         11 . The method of  claim 1  wherein the electrocardiogram signal is measured with electrodes injected and/or implanted into the patient. 
     
     
         12 . The method of  claim 10  wherein an adherent patch that supports a processor is adhered to the patient and the incidence of cardiac arrhythmias is determined with the processor when the patch is adhered to the patient, and wherein processor transmits the incidence of arrhythmias to the remote site to determine the risk of impending decompensation. 
     
     
         13 . The method of  claim 10  further comprising transmitting the electrocardiogram signal to an intermediate device to determine the incidence of arrhythmias and wherein the incidence of arrhythmias is transmitted from the intermediate device to the remote site where the risk of the impending cardiac decompensation is determined. 
     
     
         14 . The method of  claim 1 , wherein: determining the incidence of cardiac arrhythmias from the electrocardiogram signal comprises determining an incidence of premature ventricular contraction (PVC) from the electrocardiogram signal; and determining the risk of impending decompensation comprises determining the risk of impending decompensation based in part on the incidence of PVC. 
     
     
         15 . A system to detect impending cardiac decompensation of a patient, the system comprising: circuitry to measure an electrocardiogram signal of the patient; circuitry to measure a bioimpedance of the patient and to determine from the measured bioimpedance a measure of respiration of the patient; and one or more processors comprising tangible media in communication with the circuitry, the one or more processors configured to determine an incidence of cardiac arrhythmias from the electrocardiogram signal and determine a risk of impending decompensation in response to a combination of the respiration and the incidence of cardiac arrhythmias. 
     
     
         16 . The system of  claim 15 , wherein the one or more processors are configured to determine an incidence of premature ventricular contraction (PVC), and to determine the risk of impending decompensation in part in response to the incidence of PVC. 
     
     
         17 . The system of  claim 15 , wherein: the circuitry to measure the electrocardiogram signal of the patient and the circuitry to measure the bioimpedance of the patient are disposed on an adherent patch configured to adhere to the patient for at least seven days and to continuously monitor the electrocardiogram signal and the bioimpedance for the at least seven days; the one or more processors comprise a local processor disposed in the adherent patch, the local processor configured to determine the incidence of cardiac arrhythmias; and the one or more processors further comprise a remote processor system disposed at a remote location, the remote processor system configured to determine the risk of impending decompensation. 
     
     
         18 . The system of  claim 17 , further comprising an intermediate device configured to receive information wirelessly from the adherent patch and to transmit information to the remote processor system for use in determining the risk of impending decompensation. 
     
     
         19 . A computer-readable storage medium comprising a set of instructions for a computer system to evaluate a risk of an impending cardiac decompensation of a patient, the set of instructions comprising: an input routine operatively associated with a source of electrocardiogram data from the patient and bioimpedance data from the patient; a run routine to determine form the bioimpedance data a respiration data of the patient, and to determine a risk of the impending cardiac decompensation of the patient with the source of electrocardiogram data and respiration data; and an output routine providing the risk of the impending decompensation available for external use outside the computer system. 
     
     
         20 . The computer readable storage medium of  claim 19 , wherein the input routine, the run routine and the output routine are located on a server at a remote site.