SYSTEMS AND METHODS FOR DETERMINING OPTIMAL INTERVENTRICULAR PACING DELAYS BASED ON ELECTROMECHANICAL DELAYS

摘要

Techniques are provided for use with implantable medical devices such as pacemakers for optimizing interventricular (VV) pacing delays for use with cardiac resynchronization therapy (CRT). In one example, ventricular electrical depolarization events are detected within a patient in whom the device is implanted. The onset of isovolumic ventricular mechanical contraction is also detected based on cardiomechanical signals detected by the device, such as cardiogenic impedance (Z) signals, S1 heart sounds or left atrial pressure (LAP) signals. Then, an electromechanical time delay (T_QtoVC) between ventricular electrical depolarization and the onset of isovolumic ventricular mechanical contraction is determined. VV pacing delays are set to minimize the time delay to the onset of isovolumic ventricular mechanical contraction. Various techniques for identifying the onset of isovolumic ventricular contraction based on Z, S1 or LAP or other cardiomechanical signals are described. In some examples, CRT nonresponders are specifically identified and/or heart failure progression is tracked.

主权项

1. A method for use with an implantable cardiac rhythm management device, the method comprising:
detecting ventricular electrical depolarization within the patient based on electrocardiac signals sensed by the device; detecting an onset of isovolumic ventricular mechanical contraction within the patient based on cardiomechanical signals sensed by the device; determining an electromechanical time delay between ventricular electrical depolarization and the onset of ventricular mechanical contraction; determining an interventricular (VV) pacing delay sufficient to minimize the time delay; and determining whether the patient is a nonresponder to cardiac resynchronization therapy (CRT) based on the time delay.