Author + information
- Aarti A. Patel,
- Vishal Parikh,
- Allen Brown,
- Joseph Coffman,
- Fadi Matar,
- Christiano Caldeira,
- Robert Hooker,
- J. Thompson Sullebarger,
- Kevin Kip,
- Arthur Labovitz and
- Allan Chen
Background: Valvuloarterial impedance Z(va) provides an estimate of the global hemodynamic load on the ventricle. Prior studies suggest that a high Z(va) is associated with poorer outcomes in patients with aortic stenosis undergoing transcatheter aortic valvular replacement(TAVR). We sought to investigate clinical and hemodynamic characteristics of an increased Z(va) in patients undergoing TAVR, and assess changes post-procedure.
Methods: A total of 100 consecutive patients with severe aortic stenosis who underwent TAVR were evaluated. Clinical, hemodynamic and echocardiographic data were analyzed at baseline as well as immediately and 30 days after TAVR. Patients were divided according to Z(va) severity (Low <3.5, Medium 3.5-4.5, High > 4.5).
Results: Patients in the high Z(va) group had higher baseline heart rates(p=0.04), brain natriuretic peptide(BNP)(p<0.001) and creatinine(p=0.04); and lower stroke volume(SV) index(p<0.0001) and cardiac output(p=0.003) amongst the 3 groups. Overall, from baseline to immediately post-TAVR, Z(va) decreased by a mean of 1.5(p<0.001), but was similar at 48 hours and 30 days. Within Z(va) subgroups, a medium and high baseline Z(va) resulted in significant reductions immediately after TAVR(-0.9 and -3, p<0.0001, respectively), and this was sustained at 30 days(p=0.002). However, a low baseline Z(va) resulted in a mean increase of 0.7 immediately, and was significant at 30 days. Comparatively, patients who had an increase vs. decrease in Z(va) of >50% 48 hours after TAVR had baseline Z(va)'s of 3(low) vs. 6(high), respectively(p=0.0043). At 30 days SV index was seen to decrease in the low Z(Va) group but increase in the medium and high (-8.5 vs. 5.2 vs. 12.5 ml/m2, p=0.04, respectively).
Conclusions: In patients undergoing TAVR, increased heart rate, BNP, and creatinine, as well as lower SV and cardiac output are associated with high Z(va). Z(va) unexpectedly increases in patients with low baseline Z(va) with a corresponding decrease in SV index. This emphasizes the concept that afterload on the heart in aortic stenosis is not isolated to the valve, and that a consideration of global load may provide further stratification when selecting patients for TAVR.
Poster Hall, Hall C
Friday, March 17, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Emerging Applications of Echocardiography
Abstract Category: 28. Non Invasive Imaging: Echo
Presentation Number: 1160-215
- 2017 American College of Cardiology Foundation