Comparison between multimodality imaging approaches for measurement of the tricuspid annulus in severe tricuspid regurgitation.

BACKGROUND: Tricuspid valve (TV) sizing is crucial for surgical or interventional procedures planning. Imaging TV is frequently challenging and often requires multimodal imaging techniques. Computed tomography (CT) is the gold standard for sizing. The authors compared measurements of the tricuspid annulus (TA) acquired using echocardiography and CT. METHODS: Thirty-six patients with severe symptomatic tricuspid regurgitation were included in this retrospective analysis. During mid-diastole, the maximal two-dimensional (2D) TA diameter was directly measured in multiple views using transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE). Three-dimensional (3D) TA size was assessed using cross-sectional long-axis and short-axis diameters, areas, and perimeters measured in the projected plane. The TA diameter was quantified by the perimeter measured on the CT images (CT imaging_indirect) and compared with echocardiography measurements. Tenting height and tenting area were also measured using TTE at mid systole. RESULTS: The long-axis dimensions measured using 3DTEE (3DTEE_direct) best correlated with the TA diameter (CT imaging_indirect) (R = 0.851, P = 0.0001) and the least discrepancies (difference 1.2 ± 2.4 mm, P = 0.012). The TA diameters quantified by the perimeters measured using 3DTEE (3DTEE_indirect) were smaller than the CT values (difference 2.5 ± 2.5 mm, P = 0.0001). The maximal dimensions directly measured by 2DTEE (2DTEE_direct) were modestly correlated with the CT values. Overall, the maximal dimensions by TTE_direct were less reliable than those by CT. TA eccentricity index correlated with the maximal tenting height and area. CONCLUSION: The patients with severe tricuspid regurgitation had a dilated and circular annulus. The long-axis TA dimensions (3DTEE_direct) were similar to the diameters (CT imaging_indirect).

Validation of methods for effective orifice area measurement of prosthetic valves by two-dimensional and Doppler echocardiography following transcatheter self-expanding aortic valve implantation.

BACKGROUND: The effective orifice area (EOA) is utilized to characterize the hemodynamic performance of the transcatheter heart valve (THV). However, there is no consensus on EOA measurement of self-expanding THV. We aimed to compare two echocardiographic methods for EOA measurement following transcatheter self-expanding aortic valve implantation. METHODS: EOA was calculated according to the continuity equation. Two methods were constructed. In Method 1 and Method 2, the left ventricular outflow tract diameter (LVOTd) was measured at the entry of the prosthesis (from trailing-to-leading edge) and proximal to the prosthetic valve leaflets (from trailing-to- leading edge), respectively. The velocity-time integral (VTI) of the LVOT (VTILVOT) was recorded by pulsed-wave Doppler (PW) from apical windows. The region of the PW sampling should match that of the LVOTd measurement with precise localization. The mean transvalvular pressure gradient (MG) and VTI of THV was measured by Continuous wave Doppler. RESULTS: A total of 113 consecutive patients were recruited. The mean age was 77.2 ± 5.5 years, and 72 patients (63.7%) were male. EOA1 with the use of Method 1 was larger than EOA2 (1.56 ± 0.39 cm2 vs. 1.48 ± 0.41 cm2, P = 0.001). MG correlated better with the indexed EOA1 (EOAI1) (r = -0.701, P < 0.001) than EOAI2 (r = -0.645, P < 0.001). According to EOAI (EOAI ≤ 0.65 cm2/m2, respectively), the proportion of sever prosthesis-patient mismatch with the use of EOA1 was lower than EOA2 (12.4% vs. 21.2%, P < 0.05). Compared with EOA2, EOA1 had lower interobserver and intra-observer variability (intra: 0.5% ± 17% vs. 3.8% ± 22%, P < 0.001; inter: 1.0% ± 9% vs. 3.5% ± 11%, P < 0.001). CONCLUSIONS: For transcatheter self-expanding valve EOA measurement, LVOTd should be measured in the entry of the prosthesis stent (from trailing-to-leading edge), and VTILVOT should match that of the LVOTd measurement with precise localization.