P5566Prognostic value of quantitative assessment of tricuspid regurgitation. Correlation between echocardiography and cardiac magnetic resonance

Background

Significant tricuspid regurgitation (TR) is related to poor prognosis independently of the etiology. TR severity and right ventricular (RV) size and function are determinant in the evaluation of patients with RT and are independently related to outcomes. While TR severity is commonly evaluated with echocardiography (echo), cardiac magnetic resonance (CMR) is the gold standard to study the RV. The association between CMR and echocardiographic measures of quantitative TR is unknown.

Purpose

Our aim was to evaluate the association between the most commonly used methods in both techniques: biplane vena contracta (VC) and effective regurgitant orifice (ERO) parameters evaluated by echo and TR volume (TRV) and TR regurgitant fraction (TRF) by CMR; secondly we aimed to evaluate the prognostic value of each parameter.

Methods

Consecutive patients in stable clinical status with significant TR evaluated in the Heart Valve Clinic between 2015–2018 with a contemporaneous echo and CMR were included. TR severity was evaluated by VC and ERO method, using EPIQ system and by VRF and TRF using a 1.5 Tesla CMR Philips scanner. End-point included cardiovascular mortality, tricuspid valve surgery or heart failure.

Results

A total of 36 patients were included (mean age was 72±7 years, 72% females, 94% functional TR). Both VC and ERO showed moderate to strong and significant correlations with VRF and TRF (table). During a median follow up of 20 months [IQR: 10–29], 38% of the patients reached the combined end point (n=7 developed right heart failure, n=11 underwent tricuspid valve surgery, and n=2 died). Patients with events showed a larger ERO and higher VRF and TRF (p<0.01 for all) and a tendency to larger VC (p=0.06). PISA, VRF and TRF were prognostic factors of the combined endpoint (PISA per 0.1 cm2, HR: 282 [3.9–20362], p=0.01; VC per 1 mm, HR 1.27 [0.98–1.64] p=0.06; VRF per 1ml: HR: 1.02 [1.005–1.025], p=0.003; FRT per 1%, HR: 219.5 [4.8–9897], p=0.06). A value of PISA of 0.42, of VRF of 46 ml and FRV of 43% reached the best accuracy to predicted poor outcomes (p<0.01 for all).

Table 1. Bivariate correlations ERO VC Regurgitant volume by CMR R=0.57, p=0.004 R=0.55, p=0.003 Regurgitant fraction by CMR R=0.61, p<0.001 R=0.56, p=0.01

Conclusion

Validated echocardiographic parameters of TR are significantly correlated with quantitative measures by CMR. PISA by echo, and VRF and FRV by CMR are predictive of impaired prognosis. Further studies confirming our CMR cut-off values of poor outcomes are needed for clinical implementation.