Patent ID: 6873870

Claim:
A method for distinguishing a hemodynamically stable tachycardia from a hemodynamically unstable tachycardia, comprising: sensing a heart rate; comparing the heart rate to a heart rate threshold value; monitoring a blood pressure sensor upon detecting the heart rate greater than the heart rate threshold value to detect a substantial drop in blood pressure; invoking a first number of intervals detected (NID) threshold up detecting the heart rate greater than the heart rate threshold value if a substantial drop in blood pressure is not detected; invoking a second NID threshold that is lower than the first NID threshold upon detecting a substantial drop in blood pressure; counting a consecutive number at intervals in which the heart rate is greater than the heart rate threshold value; making a tachycardia detection if the consecutive number of intervals satisfies the invoked NID threshold, the tachycardia detection being a detection of a hemodynamically stable tachycardia if the first NID threshold is invoked and the tachycardia detection being a detection of a hemodynamically unstable tachycardia if the second NID threshold is invoked; and delivering a first low power tachycardia response therapy upon making a tachycardia detection that the tachycardia is a hemodynamically stable tachycardia and delivering a second high power tachycardia response therapy upon detection that the tachycardia that is a hemodynamically unstable tachycardia.