Mitral and Tricuspid Valves Percutaneous Repair in Patients with Advanced Heart Failure: Panacea, or Pandora's Box?

Perioperative Right Ventricular Dysfunction and Abnormalities of the Tricuspid Valve Apparatus in Patients Undergoing Cardiac Surgery

Right ventricular (RV) dysfunction frequently occurs after cardiac surgery and is linked to adverse postoperative outcomes, including mortality, reintubation, stroke, and prolonged ICU stays. While various criteria using echocardiography and hemodynamic parameters have been proposed, a consensus remains elusive. Distinctive RV anatomical features include its thin wall, which presents a triangular shape in a lateral view and a crescent shape in a cross-sectional view. Principal causes of RV dysfunction after cardiac surgery encompass ischemic reperfusion injury, prolonged ischemic time, choice of cardioplegia and its administration, cardiopulmonary bypass weaning characteristics, and preoperative risk factors. Post-left ventricular assist device (LVAD) implantation RV dysfunction is common but often transient, with a favorable prognosis upon resolution. There is an ongoing debate regarding the benefits of concomitant surgical repair of the RV in the presence of regurgitation. According to the literature, the gold standard techniques for assessing RV function are cardiac magnetic resonance imaging and hemodynamic assessment using thermodilution. Echocardiography is widely favored for perioperative RV function evaluation due to its accessibility, reproducibility, non-invasiveness, and cost-effectiveness. Although other techniques exist for RV function assessment, they are less common in clinical practice. Clinical management strategies focus on early detection and include intravenous drugs (inotropes and vasodilators), inhalation drugs (pulmonary vasodilators), ventilator strategies, volume management, and mechanical support. Bridging research gaps in this field is crucial to improving clinical outcomes associated with RV dysfunction in the near future.

Percutaneous mitral and tricuspid edge-to-edge repair as a bridge therapy to heart transplantation in advanced heart failure secondary to human immunodeficiency virus: a case report

Background

Patients with end-stage heart failure (HF) and severe pulmonary hypertension (PH) are not eligible for heart transplant due to high mortality risk. Percutaneous interventions as edge-to-edge repair of the mitral/tricuspid valves are a safe and effective therapy as a bridge for transplantation in patients who have contraindications to heart transplantations (HTs).

Case summary

A 44-year-old man with a previous diagnosis of infection by human immunodeficiency virus (HIV) was admitted at the emergency room for exertional dyspnoea. He was diagnosed with a decompensated heart failure with reduced ejection fraction (HFrEF), severe mitral and tricuspid regurgitation, and high probability of PH. He presented poor response to guided medical treatment, even after implantable cardiac resynchronization therapy defibrillator (CRT-D). He was listed for a cardiac transplant, but after right catheterization, he was not an ideal candidate for transplantation, so it was decided to undergo percutaneous mitral and tricuspid edge-to-edge repair as a bridge to transplantation. The post-operative course was uneventful, with significant improvement in New York Heart Association functional class. The patient underwent a successful heart transplant 10 months after the procedure.

Discussion

In patients with advanced HF due to HIV, HT is an adequate treatment option. When there are functional mitral and tricuspid regurgitation and severe PH, despite optimal treatment according to current guidelines, percutaneous mitral and tricuspid repair therapy appears to be safe and effective for control of severe PH as a bridge measure for cardiac transplantation.

Functional Mitral and Tricuspid Regurgitation across the Whole Spectrum of Left Ventricular Ejection Fraction: Recognizing the Elephant in the Room of Heart Failure

Functional mitral regurgitation (FMR) and tricuspid regurgitation (FTR) occur due to cardiac remodeling in the presence of structurally normal valve apparatus. Two main mechanisms are involved, distinguishing an atrial functional form (when annulus dilatation is predominant) and a ventricular form (when ventricular remodeling and dysfunction predominate). Both affect the prognosis of patients with heart failure (HF) across the entire spectrum of left ventricle ejection fraction (LVEF), including preserved (HFpEF), mildly reduced (HFmrEF), or reduced (HFrEF). Currently, data on the management of functional valve regurgitation in the various HF phenotypes are limited. This review summarizes the epidemiology, pathophysiology, and treatment of FMR and FTR within the different patterns of HF, as defined by LVEF.

Tricuspid Valve Geometrical Changes in Patients with Functional Tricuspid Regurgitation: Insights from a CT Scan Analysis Focusing on Commissures

BACKGROUND

Cardiac computed tomography (CT) provides important insights into the geometrical configuration of the tricuspid valve (TV). The purpose of the present study was to assess the geometrical changes of TV in patients with functional tricuspid regurgitation (TR) using novel CT scan parameters and to correlate these findings with echocardiography.

METHODS

This single-center study enrolled 86 patients undergoing cardiac CT and divided them into two groups according to the presence or not of severe TR (43 patients with TR ≥ 3+ and 43 controls). The measurements collected were as follows: TV annulus area and perimeter, septal-lateral and antero-posterior annulus diameters, eccentricity, distance between commissures, segment between the geometrical centroid and commissures, and the angles of commissures.

RESULTS

We found a significant correlation between all annulus measurements and the grade of TR, except in regard to angles. TR ≥ 3+ patients had significantly larger TV annulus area and perimeter, larger septal-lateral, and antero-posterior annulus dimensions, as well as larger commissural distance and centroid-commissural distance. In patients with TR ≥ 3+ and controls, the eccentricity index predicted a circular shape and an oval shape of the annulus, respectively.

CONCLUSIONS

These novel CT variables focusing on commissures increase the anatomical understanding of the TV apparatus and the TV geometrical changes in patients with severe functional TR.

Edge-to-Edge Repair for Tricuspid Valve Regurgitation. Preliminary Echo-Data and Clinical Implications from the Tricuspid Regurgitation IMAging (TRIMA) Study

Background: The natural history of tricuspid valve regurgitation (TR) is characterized by poor prognosis and high in-hospital mortality when treated with isolated surgery. We report the preliminary echocardiographic and procedural results of a prospective cohort of symptomatic patients with high to prohibitive surgical risk and at least severe TR who underwent transcatheter edge-to-edge repair through the TriClipTM system. Methods: From June 2020 to March 2022, 27 consecutive patients were screened, and 13 underwent transcatheter TriClipTM repair. In-hospital, 30-day and six-month clinical and echocardiographic outcomes were collected. Results: Nine patients had severe, three massive and one baseline torrential TR. Sustained TR reduction of ≥1 grade was achieved in all patients, of which 90% reached a moderate TR or less. On transthoracic echocardiographic examination, there were significant reductions in vena contracta width (p < 0.001), effective regurgitant orifice area (p < 0.001) and regurgitant volume (p < 0.001) between baseline and hospital discharge. We also observed a significant reduction in tricuspid annulus diameter (p < 0.001), right ventricular basal diameter (p = 0.001) and right atrial area (p = 0.026). Conclusion: Treatment with the edge-to-edge TriClip device is safe and effective. The resulting echocardiographic improvements indicate tricuspid valve leaflet approximation does not just significantly reduce the grade of TR but also affects adjacent structures and improves right ventricular afterload adaptation.

Novel Computed Tomography Variables for Assessing Tricuspid Valve Morphology: Results from the TRIMA (Tricuspid Regurgitation IMAging) Study

BACKGROUND

Computed tomography (CT) is the recommended imaging technique for defining the anatomical suitability for current transcatheter technologies and planning tricuspid valve (TV) intervention. The aim of the Tricuspid Regurgitation IMAging (TRIMA) study was to assess the geometrical characteristics of the TV complex using novel CT parameters.

METHODS

This prospective, single-center study enrolled 22 consecutive patients with severe tricuspid regurgitation, who underwent a cardiac CT study dedicated to the right chambers. The following variables were obtained: annulus area and perimeter, septal-lateral and antero-posterior diameters, tenting height, and anatomical regurgitant orifice area. Moreover, the following novel annular parameters were assessed: distance between commissures, distance between TV centroid and commissures, and angles between centroid and commissures.

RESULTS

A significant phasic variability during the cardiac cycle existed for all variables except for eccentricity, angles, and distance between the postero-septal and antero-posterior commissure and distance between the centroid and antero-posterior commissure. There was a significant relationship between the TV annulus area and novel annular parameters, except for annular angles. Additionally, novel annular variables were found to predict the annulus area.

CONCLUSIONS

These novel additional variables may provide an initial platform from which the complexity of the TV annular morphology can continue to be better understood for further improving transcatheter therapies.

Use of Cardiac Contractility Modulation as Bridge to Transplant in an Obese Patient With Advanced Heart Failure: A Case Report

Cardiac contractility modulation (CCM) is a novel device-based therapy in patients with heart failure with reduced ejection fraction (HFrEF). In randomized clinical trials and real-life studies, CCM has been shown to improve exercise tolerance and quality of life, reverse left ventricular remodeling and reduce hospitalization in patients with HFrEF. In this case report, we describe for the first time the use of CCM as a “bridge to transplant” in a young obese patient with advanced heart failure due to non-ischemic dilated cardiomyopathy. The patient had a poor quality of life and frequent heart failure-related hospitalizations despite the optimal medical therapy and, due to obesity, a suitable heart donor was unlikely to be identified in the short term and due to severe obesity risk of complications after implantation of a left ventricular assist device (LVAD) was very high.

Transcatheter Tricuspid Valve Therapy: From Anatomy to Intervention

Nowadays, severe symptomatic tricuspid regurgitation (TR) affects millions of persons worldwide. However, the benefit of surgical correction of isolated secondary TR remains controversial because of the increased risk of periprocedural mortality and morbidity. In recent years, novel transcatheter tricuspid valve interventions (TTVI) were developed to treat TR, so that TTVI is currently considered in symptomatic, inoperable, anatomically eligible patients. TTVI can be divided into these five domains: edge-to-edge leaflet repair, tricuspid annuloplasty, caval implants, spacer, and total valve replacement. Each transcatheter intervention needs specific imaging protocols for assessing the anatomical feasibility and consequentially predicting the procedural success. This review summarizes the available multimodality imaging tools for screening patients with TR, and identifies anatomical characteristics to choose the best option for the patient.