Key Points
- The aim is to evaluate and optimize calibration techniques for left ventricular volume measurements using conductance catheters in mice.
- In vivo left ventricular volumes were measured in mice (n = 52) using a Millar conductance catheter.
- Measurements were compared with MRI-derived volumes using different calibration techniques.
- Calibration methods included injection of hypertonic saline into the pulmonary artery and independent measurement of stroke volume.
- Significant correlations found between conductance catheter volumes (V(CC)) and MRI-derived volumes (R(2) = 0.85 for EDV, R(2) = 0.88 for ESV, P < 0.01).
- Underestimation observed in volume measurements: EDV = -17.3 microl, ESV = -8.8 microl with specified 95% CI.
- Calibration using hypertonic saline injection into the pulmonary artery yielded higher accuracy than intravenous injection.
Structured PICO
IInterventionLeft ventricular volume measurement using a Millar conductance catheter (SPR-839) with various calibration techniques (e.g., hypertonic saline injection in pulmonary artery)
CComparatorMRI-derived volumes (V(MRI))
OOutcomeCorrelation between conductance catheter-derived volumes (V(CC)) and MRI-derived volumes (V(MRI)) for end-diastolic volume (EDV) and end-systolic volume (ESV)surrogate
Optimized calibration techniques, specifically pulmonary artery injection of hypertonic saline, enable reliable left ventricular volume estimation with a conductance catheter in mice, despite some underestimation compared to MRI.