The reliability of cardiogenic impedance and correlation with echocardiographic and plethysmographic parameters for predicting CRT time intervals post implantation
2013 (English)In: Journal Of Interventional Cardiac Electrophysiology, ISSN 1383-875X, Vol. 37, no 2, 155-162 p.Article in journal (Refereed) Published
Encouraging data have been reported on the use of cardiogenic impedance (CI) in cardiac reshynchronization therapy (CRT) optimization. The purpose of this study was to: evaluate the stability of certain CI vectors 24 hours post implantation, study the correlation between these CI signals and selected echocardiographic parameters, examine the possibility of non-invasive calibration of patient-specific impedance-based prediction models.
Methods and results
Thirteen patients received a CRT-D device with monitor capability of the dynamic impedance between several electrodes. At implantations patient-specific impedance-based prediction models were created for identification of optimal atrioventricular (AV) and interventricular (VV) delays and calibrated on invasive measurements of left ventricular contractility (LV dP/dtmax). Simultaneously non-invasive measurements of LV dP/dtmax and stroke volume (SV) were obtained using a finger plethysmograph. Patients were re-evaluated with echocardiography and new CI measurements the day after implantation.The haemodynamic benefit achieved by optimal VV setting according to the patient-specific impedance-based prediction models at follow-up was not as large as the one obtained at implantation. In a multivariate partial least square regression analysis a correlation was found between aortic VTI and a generic linear combination of CI features (P<0,005). No correlation was found between the patient-specific impedance-based prediction models and the non-invasive measurements of LV dP/dtmax and SV.
Cardiogenic impedance signals can be used to optimize CRT settings but seems less feasible as an ambulatory tool since calibration is required. The positive correlation between aortic-VTI and CI measurements seems promising; although a larger cohort is required to create an echocardiography-based patient-specific model.
Place, publisher, year, edition, pages
2013. Vol. 37, no 2, 155-162 p.
cardiac resynchronization therapy, cardiogenic impedance, device optimization
Cardiac and Cardiovascular Systems
IdentifiersURN: urn:nbn:se:uu:diva-179547DOI: 10.1007/s10840-013-9795-5ISI: 000321268700005PubMedID: 23625092OAI: oai:DiVA.org:uu-179547DiVA: diva2:546246