부산대학교 도서관

Introduction: Transcatheter aortic valve replacement (TAVR) is an established treatment for patients with severe, symptomatic aortic stenosis (AS). Ventriculoarterial (LV-arterial) coupling defined as the ratio of total arterial elastance (Ea) to left ventricular end-systolic elastance (Ees) reflects effective cardiac energetics and is a well-accepted index for quantification of LV-arterial coupling. Despite its usefulness, estimating Ees/Ea has technical difficulties. Intrinsic Frequency (IF) method is a noninvasive and single waveform system-based approach for quantification of LV-arterial coupling. The objective of this study was to compare IF variables with Ea/Ees in predicting optimum LV-arterial energetics following TAVR.Method: Twenty-eight patients with severe AS, undergoing TAVR were included. Mean age was 85±4, 53% male with mean ejection fraction 59±6.4. IFs during systole (ω1), diastole (ω2), and total IF variation (Δω=ω1-ω2) were computed from the ascending aortic pressure waveforms at baseline and following TAVR. Ea/Ees was computed using single-beat technique proposed by Takeuchi et al. (Circulation. 1991;83(1):202-212).Results: There was a significant decrease in Ea/Ees (p<0.001) toward optimum coupling immediately after TAVR (Figure 1a). There was a statistically significant correlation between Ea/Ees and Δω (r= 0.68, p<0.01) (Figure 1b).Conclusion: IF appears to be an accurate and reliable index for quantification of LV-arterial coupling given significant concordance with Ea/Ees. The management of patients with acutely altered hemodynamic states post TAVR can benefit from the assessment of LV-arterial coupling. Since IFs can be measured noninvasively using hand-held devices (e.g. an iPhone), this approach should broaden the clinical applicability of this useful parameter for assessing systolic function, therapeutic response and ventricular-arterial interaction post TAVR.