Author + information
- Jose Ricardo Po,
- Matthew Tong,
- Talha Meeran,
- Alekhya Potluri,
- Mark Doyle,
- Amresh Raina and
- Robert Biederman
Background: The use of the Fick principle and the thermodilution (TD) method via right heart catheterization (RHC) has remained the most reliable means of cardiac output (CO) measurement. Using CMR, phase velocity mapping (PVM) is a non-invasive, rapid, highly reproducible technique to measure CO. The use of PVM was previously validated in a small cohort of patients. The objective of our study is to determine the accuracy of CMR as compared to RHC in measuring CO in pts with advanced pulmonary hypertension (PH).
Methods: We retrospectively identified PH pts who underwent CMR and RHC within 1 month. Demographic and hemodynamic measurements were obtained. Invasive CO was calculated via the Fick principle and TD. Measurement of CO by CMR was performed by PVM at the proximal aorta. Correlation coefficients of the CO measurement were calculated. Bland-Altman analysis was performed to assess the bias and differences between pairs of measurements.
Results: A total of 108 cases were analyzed (mean age: 60 years, SD: 12). Seventy four (68% F) and 72 (66%) were WHO group I. There was very good correlation between PVM-Fick (r = 0.72) and PVM-TD (r = 0.73). Bland-Altman analysis showed PVM-Fick had a mean difference of 0.40 and SD of 1.07 L/min, PVM-TD had a mean difference of 1.19 and SD of 1.21 L/min, and Fick-TD had a mean difference of 0.77 and SD of 1.23 L/min. For same day PVM and RHC (73 cases), analyses were similar (PVM-Fick mean = 0.32, SD = 1.14, r = 0.71; PVM-TD mean = 1.09, SD = 1.12, r = 0.78; Fick-TD mean = 0.71, SD = 1.18, r = 0.80). The same day PVM-Fick mean difference in stroke volume was 3.6 ml, similar to the original validation paper. Ranking of contribution to SD showed that PVM contributed the least variation followed by Fick then TD.
Conclusions: Non-invasive measurement of CO using PVM correlates very well to invasive measurement using RHC in both one month and same day analyses. However, CMR measured CO is superior in terms retaining the least amount of intrinsic variation. This demonstrates the advantage of CMR in determining CO without the need to measure oxygen consumption or the need for rigorous invasive techniques. This has particular inherent advantages to PH patients with their obligate requirements for repetitive RHC's.
Poster Hall, Hall C
Friday, March 17, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Non Invasive Imaging: MR Heart Failure and Pulmonary Hypertension
Abstract Category: 29. Non Invasive Imaging: MR
Presentation Number: 1158-205
- 2017 American College of Cardiology Foundation