A new and simple method for clarifying the severity of tricuspid regurgitation

No gold standard exists for grading tricuspid regurgitation (TR) severity. We developed a simple parameter, the right ventricular (RV) early inflow-outflow (RVEIO) index, using the early diastolic filling velocity and RV outflow velocity integrated over the systolic ejection period. We hypothesized that this index would help identify severe TR in clinical practice.

We obtained data from routine transthoracic echocardiograms. All records reporting moderate (n=395) or severe (n=395) TR were reanalyzed to measure vena contracta (VC) width, TR jet area, effective regurgitant orifice (EROA) derived with the proximal isovelocity surface area method, RVEIO index, and right-sided chamber volumes.

Significant linear trends were demonstrated for right atrial volume index, end-diastolic volume index, E-wave velocity, RV velocity time integral, TR jet area, VC width, and EROA with increasing TR severity. Independent predictors of severe RT included RVEIO index ≥ 10, VC width ≥ 0.7 cm, TR jet area>10 cm² , and EROA ≥ 0.4 cm² .

RVEIO index is a useful, simple, accurate, and independent predictor of severe TR that adds incrementally to traditional methods of quantifying TR severity. Accurate quantification and classification of TR severity is critical for clinical decision-making and management; therefore, the incorporation of RVEIO index into the integrative approach to grading TR severity should be considered.