Feasibility and accuracy of tricuspid annular displacement assessed by speckle tracking echocardiography and Doppler tissue imaging

Feasibility Value of Right Ventricular Longitudinal Shortening Fraction and the Prognostic Implications in Patients With Heart Transplantation

BACKGROUND

Right ventricular longitudinal shortening fraction (RVLSF) is a 2-dimensional speckle tracking echocardiography parameter based on tricuspid annular displacement analysis that could be used to assess right ventricular (RV) systolic function. The value of RVLSF in the assessment of RV systolic function in recipients of heart transplantation (HT) and whether RVLSF can replace strain parameters remains unknown.

METHODS AND RESULTS

A total of 153 adult patients who underwent HT were consecutively enrolled in this prospective longitudinal study. All subjects were examined by conventional transthoracic 2-dimensional echocardiography and 2-dimensional speckle tracking echocardiography to evaluate the RV end-diastolic basal diameter, RV end-diastolic area, fractional area change, peak systolic velocity of tricuspid annulus, tricuspid annular plane systolic excursion, RV free wall strain, and RVLSF. Cox proportional hazards regression was used to test if the parameters of interest had independent prognostic value for adverse outcome prediction in patients who underwent HT. A significant positive correlation was found between the measurements of RVLSF and RV free wall strain (r=0.927, P<0.001). Compared with the event-free group, the adverse outcome group displayed reduced RVLSF and RV free wall strain and higher age (P<0.001, <0.001, =0.016, respectively) in patients who underwent HT. RVLSF and RV free wall strain were independently associated with poor prognosis in multivariable analysis (both P<0.001).

CONCLUSIONS

RVLSF assessment provides an effective evaluation of RV longitudinal systolic function in the transplanted hearts and has prognostic value for adverse outcomes in patients undergoing HT.

Preload Dependency of 2D Right Ventricle Speckle Tracking Echocardiography Parameters in Healthy Volunteers: A Prospective Pilot Study

(1) Background: Right ventricular (RV) strain parameters derived from the analysis of the tricuspid annular displacement (TAD) are emergent two-dimensional speckle tracking echocardiography (2D-STE) parameter used for the quantitative assessment of RV systolic function. Few data are available regarding 2D-STE parameters and their dependency on RV preload. Our aim was to evaluate the effect of an acute change in RV preload on 2D-STE parameters in healthy volunteers. (2) Methods: Acute modification of RV preload was performed by a fluid challenge (FC): an infusion of 500 mL of 0.9% sodium chloride was given over 5 min in supine position. Preload dependency (responder group) was confirmed by a stroke volume increase of at least 10% measured by echocardiography. (3) Results: Among 32 healthy volunteers, 19 (59%) subjects were classified as non-responders and 13 (41%) as responders. In the responder group, the tricuspid annular plane systolic excursion (TAPSE) significantly increased (20 (20–23.5) mm to 24 (20.5–26.5) mm; p = 0.018), while RV strain parameters significantly decreased after FC: −23.5 ((−22.3)–(−27.3))% to −25 ((−24)–(29.6))%; p = 0.03) for RV free wall longitudinal strain and −22.8 ((−20.4)–(−30.7))% to −23.7 ((−21.2)–(−27))%; p = 0.02) for RV four-chamber longitudinal strain. 2D-STE parameters derived from the TAD analysis were not influenced by the FC (all p > 0.05). (4) Conclusions: In young, healthy volunteers, RV strain parameters and TAPSE are preload dependent, while TAD parameters were not. The loading conditions must be accounted for when evaluating RV systolic function by 2D-STE parameters.

Clinical implications of antegrade diastolic pulmonary artery flow in adults

BACKGROUND

End-diastolic opening of the pulmonary valve and subsequent antegrade diastolic pulmonary artery flow (ADPAF) reflect restrictive right ventricular (RV) physiology in children. However, this has attracted little attention in adults.

PURPOSE

To clarify the clinical implications of ADPAF in adults.

METHODS AND RESULTS

The study population consisted of 23,049 consecutive adult patients who underwent echocardiography in our hospital between 2008 and 2015. ADPAF was found in 17 patients (0.07%). The simultaneous recording of RV and pulmonary artery pressures revealed marked elevation of RV diastolic pressure, which exceeded pulmonary artery pressure at the time of atrial contraction. These results suggested that ADPAF implies RV restriction. Based on the level of tricuspid annular plane systolic excursion (TAPSE), we classified these patients into two groups: reduced RV function (R-RVF) group (12 patients with TAPSE <17 mm) and preserved RV function (P-RVF) group (5 patients with TAPSE ≥17 mm). In the R-RVF group, four patients died, one patient underwent left ventricular assist device implantation, and two patients underwent unplanned hospitalization for heart failure during follow-up. The R-RVF group had poorer prognosis and higher mortality rate compared with the P-RVF group.

CONCLUSIONS

ADPAF reflects RV restriction in adults. ADPAF suggests a less favorable prognosis in patients with R-RVF.

Prophylactic Ligature of AV Fistula Prevents High Output Heart Failure after Kidney Transplantation

BACKGROUND

Arteriovenous (AV) fistulas are considered the gold standard for ensuring safe and long-term vascular access in patients with haemodialysis-dependent end-stage renal disease. However, previous studies demonstrated that high-flow AV fistulas might add additional cardiovascular burden in the post-transplant setting, leading to frequent fistula closure in this population. Currently, there is no consensus regarding management of high-flow fistulas in post-transplant patients with stable kidney function. The present randomized controlled trial examines the effect of prophylactic AV fistula closure on high-output heart failure.

METHODS

Twenty-eight kidney transplant patients with stable graft function, absence of pre-existing severe cardiac failure, and brachial arterial flow rate of at least 1,500 mL/min were recruited and randomized in a 1:1 ratio to an intervention and control group, respectively. The intervention group was subject to immediate fistula ligature. Patients within the control group were referred to fistula ligature only if the main study endpoint high-output heart failure was reached. The latter was defined by the presence of at least 1 clinical sign (i.e., worsening NYHA score) and at least 2 of the following echocardiographic parameters: diameter of right atrium (major) >53 mm, right atrium (minor) >44 mm, inferior vena cava ≥21 mm, right pulmonary artery >20 mm, TAPSE <16 mm, systolic pulmonal artery pressure >40 mm Hg, and/or left ventricular eccentricity index <1. During a 24-month follow-up period, quarterly measurements of kidney function, NT-proBNP, and lactate dehydrogenase as well as a biannual echocardiographic check-up were performed.

RESULTS

High-output heart failure attributable to high-flow fistula was reported in 5 of 13 control patients (38.5%), whereas no patient in the intervention group presented with clinical and echocardiographic signs of high-output heart failure during the follow-up period. Thus, prophylactic ligature of high-flow fistulas avoided high-output heart failure in our patient population (p = 0.013). Three patients in the control group, however, had to undergo fistula ligature due to aneurysm formation (n = 2) and steal phenomenon (n = 1). Median NT-proBNP levels decreased from 317 ng/L pre-ligature to 223 ng/L post-ligature (p = 0.003). Serum creatinine levels did not significantly differ before and after AV fistula ligature (1.69 vs. 1.60 mg/dL, respectively, p = 0.059). Improvement of echocardiographic findings (e.g., a decrease in systolic pulmonary arterial pressure) was found in 7 of 8 ligature patients but did not reach statistical significance.

CONCLUSION

Prophylactic ligature of high-flow AV fistulas after kidney transplantation can avoid high-output heart failure, and a more liberal approach to close AV fistulas might be justified.