Right atrial volume is a major determinant of tricuspid annulus area in functional tricuspid regurgitation: a three-dimensional echocardiographic study.

AIMS: The aim of this study is to explore the relationships of tricuspid annulus area (TAA) with right atrial maximal volume (RAVmax) and right ventricular end-diastolic volume (RVEDV) in healthy subjects and patients with functional tricuspid regurgitation (FTR) of different aetiologies and severities. METHODS AND RESULTS: We enrolled 280 patients (median age 66 years, 59% women) with FTR due to left heart disease (LHD), pulmonary hypertension (PH), corrected tetralogy of Fallot (TOF), chronic atrial fibrillation (AF), and 210 healthy volunteers (45 years, 53% women). We measured TAA at mid-systole and end-diastole, tenting volume of tricuspid leaflets, RAVmax, and RVEDV by 3D echocardiography. Irrespective of TA measurement timing, TAA correlated more closely with RAVmax than with RVEDV in both controls and FTR patients. On multivariable analysis, RAVmax was the most important determinant of TAA, accounting for 41% (normals) and 56% (FTR) of TAA variance. In FTR patients, age, RVEDV, and left ventricular ejection fraction were also independently correlated with TAA. RAVmax (AUC = 0.81) and TAA (AUC = 0.78) had a greater ability than RVEDV (AUC = 0.72) to predict severe FTR (P < 0.05). Among FTR patients, those with AF had the largest RAVmax and smallest RVEDV. RAVmax and TA were significantly dilated in all FTR groups, except in TOF. PH and TOF had largest RVEDV, yet tenting volume was increased only in PH and LHD. CONCLUSION: RA volume is a major determinant of TAA, and RA enlargement is an important mechanism of TA dilation in FTR irrespective of cardiac rhythm and RV loading conditions.

Prognostic validation of partition values for quantitative parameters to grade functional tricuspid regurgitation severity by conventional echocardiography.

AIMS: Quantitative echocardiography parameters are seldom used to grade tricuspid regurgitation (TR) severity due to relative paucity of validation studies and lack of prognostic data. To assess the relationship between TR severity and the composite endpoint of death and hospitalization for congestive heart failure (CHF); and to identify the threshold values of vena contracta width (VCavg), effective regurgitant orifice area (EROA), regurgitant volume (RegVol), and regurgitant fraction (RegFr) to define low, intermediate, and high-risk TR based on patients' outcome data. METHODS AND RESULTS: A cohort of 296 patients with at least mild TR underwent 2D, 3D, and Doppler echocardiography. We built statistical models (adjusted for age, NYHA class, left ventricular ejection fraction, and pulmonary artery systolic pressure) for VCavg, EROA, RegVol, and RegFr to study their relationships with the hazard of outcome. The tertiles of the derived hazard values defined the threshold values of the quantitative parameters for TR severity grading. During 47-month follow-up, 32 deaths and 72 CHF occurred. Event-free rate was 14%, 48%, and 93% in patients with severe, moderate, and mild TR, respectively. Severe TR was graded as VCavg > 6 mm, EROA > 0.30 cm2, RegVol > 30 mL, and RegF > 45%. CONCLUSION: This outcome study demonstrates the prognostic value of quantitative parameters of TR severity and provides prognostically meaningful threshold values to grade TR severity in low, intermediate, and high risk.

[Current clinical applications of three-dimensional echocardiography]. / Principali applicazioni dell'ecocardiografia tridimensionale nell'attuale pratica clinica.

Three-dimensional echocardiography (3DE) represents one of the most innovative advances in cardiovascular imaging over the last 20 years. Recent technological developments have fueled the full implementation of 3DE in clinical practice and expanded its impact on patient diagnosis, management, and prognosis. One of the most important clinical applications of transthoracic 3DE has been the quantitation of cardiac chamber volumes and function. The main limitations affecting two-dimensional echocardiography calculations of chamber volumes (i.e. geometric assumptions about cardiac chamber shape and view foreshortening) are overcome by 3DE that allows an actual measurement of their volumes. Transesophageal 3DE has been applied mainly to assess the anatomy and function of heart valves, congenital defects and masses in the beating heart. As reparative cardiac surgery and transcatheter procedures have become more and more popular to treat structural heart disease, transesophageal 3DE has become not only one of the main imaging modalities for procedure planning but also for intra-procedural guidance and assessment of procedural results. New image rendering modalities such as 3D printing, holographic display, and fusion of 3DE images with other radiological or nuclear modalities will further expand the clinical applications and indications of 3DE.

Three-dimensional echocardiography to assess left ventricular geometry and function.

Introduction: Quantification of left ventricular (LV) size and function represents the most frequent indication for an echocardiographic study. New echocardiographic techniques have been developed over the last decades in an attempt to provide a more comprehensive, accurate, and reproducible assessment of LV function.Areas covered: Although two-dimensional echocardiography (2DE) is the recommended imaging modality to evaluate the LV, three-dimensional echocardiography (3DE) has proven to be more accurate, by avoiding geometric assumptions about LV geometry, and to have incremental value for outcome prediction in comparison to conventional 2DE. LV shape (sphericity) and mass are actually measured with 3DE. Myocardial deformation analysis using 3DE can early detect subclinical LV dysfunction, before any detectable change in LV ejection fraction.Expert opinion: 3DE eliminates the errors associated with foreshortening and geometric assumptions inherent to 2DE and 3DE measurements approach very closely those obtained by CMR (the current reference modality), while maintaining the unique clinical advantage of a safe, highly cost/effective, portable imaging technique, available to the cardiologist at bedside to translate immediately the echocardiography findings into the clinical decision-making process.