Case Report: Reconstruction of the Right Atrium With the Left Atrial Appendage

We herein present a case of infective endocarditis of the mitral valve and a paravalvular abscess around the tricuspid valve. Preoperative blood culture confirmed the presence of pathogenic diphtheroids. During the operation, an unexpected infection of the free wall of the right atrium (RA) near the tricuspid annulus was found. We harvested the left atrial appendage (LAA) en bloc. After resection of the infected and abnormal tissues, the resected LAA was used to reconstruct the RA. The infected mitral valve was replaced with a mechanical valve without any accident. Postoperative echocardiography showed that the RA had a supple shape, with no kinking.

Split Accessory Pathway Potentials in a Patient with Antidromic AVRT

A 27-year-old female presenting palpitation without ECG documentation underwent electrophysiology study. EP study revealed atrioventricular accessory pathway with poor and unidirectional pathway conduction, and a fasciculoventricular pathway. During isoproterenol infusion, delta wave promptly became prominent, after which an antidromic AV reentrant tachycardia was induced. When the pathway was mapped, widely split double pathway potentials were observed at 12 o’clock site of tricuspid annulus during mild preexcitation, demonstrating an example of intra-pathway conduction delay, which can be reversed by isoproterenol. Ablation at the site caused accelerated pathway rhythm and eliminated the pathway, rendering the tachycardia non-inducible.

Morphological Changes of The Tricuspid Valve Complex in Functional Tricuspid Regurgitation On Contrast-Enhanced Computed Tomography

Background: Whether it is possible to perform morphological evaluation of functional tricuspid regurgitation (FTR) on contrast-enhanced computed tomography (CT) was examined by evaluating the relationships between the parameters measured by contrast-enhanced CT and TR severity on transthoracic echocardiography.Methods: Fifty patients underwent contrast-enhanced CT. Tricuspid annulus area (TAA), tricuspid annulus circumference (TAC), right ventricular volume (RVV), and the distances between the tips and bases of the papillary muscles were measured on contrast-enhanced CT in diastole and systole. Fifty cases were divided into 34 in the TR ≤ mild group (none TR: 3 cases, trivial TR: 24 cases, mild TR: 7 cases), and 16 in the TR ≥ moderate group (moderate TR: 8 cases, severe TR: 8 cases) using the TR grade measured by transthoracic echocardiography, and then differences between the groups were examined.Results: Significant differences were found in TAA, TAC, and RVV (p<0.01) and the distances between the tips of the anterior and posterior papillary muscles (p<0.05) in both diastole and systole. Since the septal papillary muscle could not be identified in 18 cases (36.0%), only the distance between the anterior and posterior papillary muscles was measurable in all cases. On subgroup analysis, risk factors for FTR ≥ moderate were evaluated by multiple logistic regression analysis. The risk factors identified in the multivariable risk factor analysis were diastolic RVV (odds ratio 1.083 [95% confidence interval 1.029-1.139]) and systolic RVV (odds ratio 0.951 [95% confidence interval 0.906-0.997 ]).Conclusions: TAA, TAC, RVV, and the distance between the tips of the anterior and posterior papillary muscles measured on contrast-enhanced CT were shown to be significantly increased in the TR ≥ moderate group. Detailed morphological assessment of FTR is possible by contrast-enhanced CT.

Mitral and tricuspid annulus disjunction frequently coexist

Background Mitral annulus disjunction (MAD) is an abnormal atrial displacement of the mitral annulus, frequently found in patients with high-risk arrhythmogenic mitral valve prolapse syndrome. It is unknown whether the annulus disjunction extends to the right side of the heart as tricuspid annulus disjunction (TAD), and whether it is associated with right ventricular electrical instability. Purpose We aimed to explore the presence of TAD, and if extended annulus disjunction was associated with ventricular arrhythmias. Methods We included patients with previously described MAD assessed by cardiac magnetic resonance imaging (CMR) in an ambispective cohort study. MAD and TAD was defined as ≥1 mm separation between the respective atrial wall-valve leaflet junction and the top of the ventricular myocardium. TAD was assessed in the lateral and inferior right ventricular free wall by means of the 4-chamber and right ventricular 2-chamber views, respectively. MAD circumference was assessed by a CMR study protocol with six left ventricular long axis views separated by 30 degrees. Mitral valve prolapse was defined as ≥2 mm superior displacement of any part of the mitral leaflets beyond the mitral annulus. Ventricular arrhythmias were defined as aborted cardiac arrest or non-sustained/sustained ventricular tachycardias recorded by electrocardiogram (ECG), stress ECG or Holter monitoring. Results We included 92 patients with MAD (62% female, age 47±16 years, 71% mitral valve prolapse). TAD was found in 48 (52%) patients, both in the lateral (n=40, 83%) and inferior (n=30, 63%) right ventricular free wall. Patients with TAD were older (age 51±16 years vs. 43±14 years, p=0.01), had greater MAD circumference (168±56° vs. 117±62°, p=0.001) and greater MAD distance (9.2±2.9 mm vs. 6.4±2.8 mm, p&lt;0.001). Additionally, patients with TAD had more frequently mitral valve prolapse (40 patients [85%] vs. 25 patients [57%], p=0.003), whereas similar frequency of bileaflet prolapse (17 patients [39%] vs. 10 patients [39%], p=0.99). Ventricular arrhythmias had occurred in 38 (41%) patients, who were younger (age 40±14 years vs. 52±15 years, p&lt;0.001) and had less frequently TAD (14 patients [37%] vs. 34 patients [63%], p=0.01; univariate odds ratio 0.34 [0.15–0.81], p=0.02). However, TAD was not associated with ventricular arrhythmias when adjusted for age (multivariate odds ratio 0.46 [0.18–1.15], p=0.10). Conclusions TAD by CMR was highly prevalent in patients with MAD and was a marker of severe annulus disjunction and mitral valve prolapse. TAD was not associated with more ventricular arrhythmias. This novel marker warrants further research to explore the clinical implications of right-sided annulus disjunction. FUNDunding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Norwegian Research Council

Flow vorticity relationships with right ventricular geometry in adult tetralogy of Fallot

Background Repaired tetralogy of Fallot adults (rToF) undergo right ventricular (RV) remodeling, in part due to volume overload of residual pulmonary regurgitation volume (PRV). Time-resolved phase-contrast cardiac magnetic resonance imaging (4D Flow MRI) enables the qualitative and quantitative measurement of altered blood flow patterns, including vorticity. Cardiac atlases allow for complex three-dimensional heart shapes to be expressed as morphometric scores. Those scores show the extent of geometrical shift and can help explore uncharted relationships between vorticity and architecture. Purpose We aimed to quantify vorticity, incorporating deep learning to enhance 4D Flow data, and correlate this with global cardiac parameters and morphometric scores. Methods 12 Adult rToF patients and 10 age-matched controls underwent 4D flow MRI and cine imaging. RV interventricular vorticity was calculated for outflow and inflow tracts. EDV, ESV and SV were computed from cines which were also used to build three-dimensional shape models. The biventricular models were projected onto an atlas generated from 95 rToF patients, and twenty-one principal component analysis shape modes were correlated with cardiac metrics and vorticity to identify global shape variations. Association between biventricular shape and vorticity was further analysed using multivariate multiple regression models. Results Strong correlation was found between PRV and the right ventricular outflow tract (RVOT) vorticity. PRV and RVOT vorticity both correlated with the same 3 shape modes (r=−0.55, −0.50 and 0.6 (p&lt;0.05) respectively for PR and r=0.63, −0.82 and 0.60 (p&lt;0.05) respectively for vorticity) i.e., the RV dilates with an increase in basal bulging, apical bulging and tricuspid annulus tilting with more severe regurgitation, as well as a smaller LV, and a paradoxical movement of the septum (Figure 1). However, RV vorticity correlated with 2 modes that did not correlate with PRV, (r=−0.62, −0.69, p&lt;0.05). With higher vorticity the RV was longer, increased tilting of the tricuspid annulus and an increased basal bulge around the tricuspid area. The multivariate analysis model demonstrated that higher vorticity was associated with displacement of the pulmonary valve and change in the RVOT length and direction. A septal displacement towards the left ventricle was observed and increased apical flatness of the RV (Figure 1). Qualitatively, vorticity in rToF group was more heterogeneous than controls (Figure 2). Conclusions Vorticity is a novel marker based on the influence of blood motion providing new insight into early diagnosis and prognosis of cardiac disease. This is the first study to examine the relationships between vorticity and regional RV shape changes in rToF. Mode associations with vorticity were different to associations with PRV. More longitudinal studies are required for standardization of change in vorticity with the disease process. FUNDunding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The New Zealand heart foundation Mode variations and morphometric model Vorticity visualization and analysis

Multimodality Imaging of the Anatomy of Tricuspid Valve

Even though the tricuspid valve is no longer “forgotten”, it still remains poorly understood. In this review, we focus on some controversial and still unclear aspects of tricuspid anatomy as illustrated by noninvasive imaging techniques. In particular, we discuss the anatomical architecture of the so-called tricuspid annulus with its two components (i.e., the mural and the septal annulus), emphasizing the absence of any fibrous “ring” around the right atrioventricular junction. Then we discussed the extreme variability in number and size of leaflets (from two to six), highlighting the peculiarities of the septal leaflet as part of the septal atrioventricular junction (crux cordis). Finally, we describe the similarities and differences between the tricuspid and mitral valve, suggesting a novel terminology for tricuspid leaflets.

Low-Dose Dobutamine Stress Echocardiography for the Early Detection of Pulmonary Arterial Hypertension in Selected Patients with Systemic Sclerosis Whose Resting Echocardioraphy Is Non-Diagnostic for Pulmonary Hypertension

Background: Dobutamine stress echocardiography (DSE) has limited application in systemic sclerosis (SSc). We examined DSE usefulness in revealing pulmonary arterial hypertension (PAH) in selected SSc patients whose resting echocardiography for pulmonary hypertension (PH) was non-diagnostic. Methods: Forty SSc patients underwent right heart catheterization (RHC) and, simultaneously, low-dose DSE (incremental doses up to 20 μg/kg/min). Inclusion criteria were: preserved left and right ventricular (RV) function (tricuspid annulus plane systolic excursion [TAPSE] ≥ 16 mm and tissue Doppler imaging-derived systolic velocity of tricuspid annulus [RVS’] > 10 cm/s), normal pulmonary function tests, and baseline maximal tricuspid regurgitation (TR) velocity of 2.7–3.2 m/s. Results: Of 36 patients who completed DSE, resting RHC diagnosed PAH in 12 patients (33.3%). At 20 μg/kg/min, patients with PAH had higher TR velocity, higher pulmonary arterial pressure measured by RHC, and lower RV inotropic response compared with patients without PAH. A cut-off value of maximal TR velocity >3.1 m/s had a sensitivity of 80%, a specificity of 84.2%, and an accuracy of 82.4% for the detection of PAH. Conclusions: Low-dose DSE has a satisfactory diagnostic accuracy for the early detection of PAH in highly selected SSc patients whose baseline echocardiographic measurements for PH lie in the gray zone.

High density mapping of atrial insertion of retrograde decremental accessory pathway 3D-illustration of accessory atrio-ventricular conduction network

We report the case of a reciprocating tachycardia using a purely retrograde decremental slow-conducting accessory pathway. High density 3D mapping of the atrial insertion reveals a large area of specific potentials at the level of the tricuspid annulus, which can be regarded as an accessory conduction network

Double-chambered right ventricle masquerading as bipartite right ventricle

A 10-day-old neonate with pulmonary consolidation was referred for echocardiography to rule out CHD. At first glance, the morphology appeared to be a bipartite right ventricle with normal tricuspid and pulmonary valves. In-depth analysis, however, of the images showed a double-chambered right ventricle, in which the inlet and outlet portions of the right ventricle were isolated from the apical component of the right ventricle, which itself communicated with the left ventricle through a ventricular septal defect. There was a normal pulmonary valve and tricuspid annulus.