Abstract 14179: Feasibility of Routine Right Heart Catheterization and Doppler Echocardiography to Obtain Measures of Right Ventricular Contractility and Pulmonary Vascular Impedance
Background: Right ventricular (RV) dysfunction confers poor prognosis in pulmonary hypertension (PH). However, predicting which patients will do poorly and when remains difficult. Hemodynamic calculations of pulmonary arterial (PA) impedance have been used to explain the altered physiology in PH, however traditional methods require high frequency response pressure measures along with simultaneous flow. We hypothesized that such measures may be feasibly obtained from standard fluid filled PA catheters and simultaneous transthoracic Doppler echocardiography.
Methods: Patients (n=8) underwent right heart catheterization with a standard 7F fluid-filled catheter and 2F solid state micromanometer pressure transducer along with simultaneous Doppler measurement of PA velocity via transthoracic echocardiography. Paired t-test and Wilcoxon signed ranks test were used to compare values and distributions, respectively.
Results: Patient characteristics: age 65 ± 12, 4 males, mean PA pressure range 17-56 mmHg. Measures of PA systolic and diastolic pressures were similar between groups (table). Measures of afterload, such as RV effective arterial elastance (Ea), impedances over the first 3 harmonics [z(0) - z(3)] were also similar. Impedances at higher harmonics [(z(4)-z(6)] tended to be overestimated with the fluid filled catheter.
Conclusion: Many advanced measures of PA load can be feasibly calculated from fluid-filled pressure transducer and simultaneous transthoracic Doppler echocardiography. However, loads at higher frequencies (above the third harmonic) must be interpreted with caution. The ability to measure PA loads due to large caliber vessels without specialized equipment may be useful in the care of PH patients.
- © 2011 by American Heart Association, Inc.