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Right and left ventricular hemodynamic performance during sustained ventricular tachycardia
T M Kolettis1, S Saksena, P Mathew
1Arrhythmia & Pacemaker Service, Eastern Heart Institute, Passaic, New Jersey, USA.
The American Journal of Cardiology
|February 1, 1997
Summary
Right ventricular pressures do not reliably reflect left ventricular changes during ventricular tachycardia (VT). Additional hemodynamic parameters are needed for implantable cardioverter-defibrillator algorithms to improve VT detection.
Area of Science:
- Cardiology
- Biomedical Engineering
- Hemodynamics
Background:
- Implantable cardioverter-defibrillator (ICD) therapy algorithms primarily use ventricular tachycardia (VT) rate for detection.
- Hemodynamic tolerance during VT is influenced by various factors, but their correlation with ventricular function is not fully understood.
- Previous studies on the utility of right ventricular (RV) hemodynamic indexes to reflect systemic hemodynamics during VT have yielded inconclusive results.
Purpose of the Study:
- To examine hemodynamic changes in both left and right ventricles during human VT episodes.
- To investigate the correlation between left ventricular (LV) and right ventricular (RV) hemodynamic indexes during VT.
- To evaluate potential new parameters for ICD detection algorithms beyond VT rate.
Main Methods:
- Simultaneous recording of aortic, LV, and RV pressures using high-fidelity pressure catheters in patients with coronary artery disease and VT.
- Induced sustained monomorphic VT in nine patients.
- Beat-to-beat analysis of hemodynamic parameters, including systolic and end-diastolic pressures, and maximal positive and negative dP/dt.
Main Results:
- During VT, LV systolic pressure decreased by 57% and RV systolic pressure by 26%, with a weak correlation (r=0.67).
- LV end-diastolic pressure increased by 26% and RV end-diastolic pressure by 74%, with no significant correlation.
- Significant correlations were observed between changes in LV and RV maximal positive dP/dt (r=0.69) and maximal negative dP/dt (r=0.71).
- A correlation was found between the decrease in RV time to end-diastolic pressure and LV systolic pressure decrease at the 10th VT beat (r=0.8).
Conclusions:
- Left and right ventricles are unequally affected hemodynamically during rapid VT.
- RV pressures alone are insufficient to reliably assess LV hemodynamic status during VT.
- Parameters like dP/dt and ventricular time intervals warrant further evaluation for inclusion in ICD algorithms for improved VT detection.