Relationship Between Leaflets and Root in Normal Aortic Valve Based on Computed Tomography Imaging: Implication for Aortic Valve Repair

Objective: By assessing the normal dimensions and the relationship between the aortic root and leaflets in Chinese population, the objective of this three-dimensional computed tomography (3DCT)-based study was to establish a matching reference for leaflets and aortic root for aortic valve (AV) repair.Method: Electrocardiogram-gated multi-detector CT was performed on 168 Chinese participants with a normal aortic valve. Measurements of the aortic annuli and leaflets were obtained. The correlations between and the ratios of the specific root and leaflet measurements were analyzed. The references for the leaflet and root dimensions were suggested based on geometric height (gH) using a linear regression equation. The utility of the ratios was tested with CT images of 15 patients who underwent aortic valve repair.Result: The mean annulus diameter (AD), sino-tubular junction (STJ) diameter, geometric height (gH), effective height (eH), free margin length (FML), commissural height (ComH), inter-commissural distance (ICD), and coaptation height (CH) were 22.4 ± 1.7 mm, 27.3 ± 2, 0.4 mm, 15.5 ± 1.7 mm, 8.9 ± 1.2 mm, 32.0 ± 3.4 mm, 17.9 ± 1.9 mm, 23.1 ± 2.3 mm, and 3.1 ± 0.6 mm, respectively. The gH/AD, FML/ICD, and eH/ComH ratios were 0.69 ± 0.07, 1.38 ± 0.08, and 0.50 ± 0.07, respectively. The gH correlated with all other leaflet and root measurements (P < 0.01), whereas the FML demonstrated a better correlation with ICD compared with gH (R2 = 0.75, and R2 = 0.37, respectively). The FML/ICD and eH/ComH ratios might be used to assess leaflet-root mismatch and post-repair leaflet billowing.Conclusion: The normal aortic valve measurements based on 3DCT revealed a specific relationship between the root and leaflets; and this will guide the development of an objective method of aortic valve repair.

Open-sleeve technique: A new approach for aortic valve leaflet reconstruction in small children

A boy was diagnosed with a unicuspid aortic valve with severe stenosis at birth. Percutaneous balloon aortic valvuloplasty was performed four times; however, he had severe heart and growth failure. Thus, aortic valve repair was performed at age 2 years and 6 months. He weighed 6.6 kg. The aortic valve annulus diameter was 9.8 mm (z value = 0.43). We report on a small toddler with congenital aortic stenosis who was successfully treated with autologous pericardial aortic valve leaflet reconstruction using the open-sleeve technique.

Aortic Valve Surgery After Neonatal Balloon Aortic Valvuloplasty in Congenital Aortic Stenosis

Background: We sought to identify predictive factors for aortic valve (AoV) surgery after neonatal balloon aortic valvuloplasty (BAV) and characterize clinical outcomes of AoV surgery after neonatal BAV. Methods: Time-to-event analysis identified predictors for AoV surgery after neonatal BAV. Clinical outcomes of AoV surgery following neonatal BAV were examined. Results: This study included 96 consecutive patients who underwent neonatal BAV for congenital aortic stenosis between 1998 and 2018, in 26 of whom a fetal BAV had been performed. Fifty-six patients underwent AoV surgery at a median age of 2.0 years. Significant risk factors for AoV surgery in univariate Cox regression (result presented as hazard ratio [HR], [95% CI]; P value) were a history of fetal BAV (HR, 4.05 [95% CI, 2.19–7.40]; P <0.001), AoV annulus diameter Z score (HR, 0.56 [95% CI, 0.43–0.75]; P =0.001), the presence of endocardial fibroelastosis (HR, 2.61 [95% CI, 1.48–4.51]; P =0.001), severe left ventricular dysfunction before neonatal BAV (HR, 1.75 [95% CI, 1.03–2.97]; P =0.04), and recent era (HR, 3.08 [95% CI, 1.68–5.91]; P =0.0002) in the entire cohort. Area under the receiver operating characteristic curve and Youden J index analysis identified a cutoff value for AoV annulus diameter Z score of −2.6 in patients without fetal BAV. In 24 patients with midterm cardiac catheterization data, univariate linear regression analysis (result presented as B coefficient [95% CI]; P ) showed that the presence of greater-than-moderate aortic regurgitation immediately after BAV (B coefficient, 4.8 [95% CI, 1.0–8.6]; P =0.018) and before AoV surgery (B coefficient, 6.1 [95% CI, 2.2–10.0]; P =0.004) were significant risk factors for elevated left ventricular end-diastolic pressure after AoV surgery, while concomitant endocardial fibroelastosis resection at AoV surgery had a protective effect (B coefficient, −3.8 [95% CI, −7.6 to −0.06]; P =0.05). Conclusions: A small AoV annulus diameter Z score with a cutoff value of −2.6 and a history of fetal BAV were significantly associated with AoV surgery after neonatal BAV. Concomitant endocardial fibroelastosis resection is recommended at AoV surgery following neonatal BAV to improve left ventricular diastolic function.

Predicting clinical outcome by indexed mitral valve tenting in functional mitral valve regurgitation

ObjectivesMitral valve (MV) tenting parameters are indicators of left ventricular remodelling severity and may predict outcome in functional mitral regurgitation (FMR). We hypothesised that indexing of MV tenting area to body surface area (BSA), to mitral annulus diameter or gender-adjusted analysis of tenting parameters may improve their prognostic value.MethodsWe identified retrospectively 240 patients with consecutive FMR (mean age 68±10 years; men=135) from our institutional database who underwent isolated MV annuloplasty during a period of 7 years (2010–2016). Using preoperative two-dimensional transthoracic echocardiographic images, MV tenting parameters including tenting area, tenting height and annulus diameter were systematically assessed. Follow-up protocol consisted of chart review and structured clinical questionnaire. Primary study endpoint was the composite of death and adverse cardiac events (ie, MV reoperation, cardiac resynchronisation therapy implantation, ventricular assist device implantation or heart transplantation).ResultsBSA-indexed MV tenting area was identified as independent predictor of primary study endpoint (HR 1.9; 95% CI 1.1 to 3.5; p=0.02). After cut-off point analysis, BSA-indexed MV tenting area >1.35 cm2/m2 was significantly associated with primary study outcome (HR 2.3; 95% CI 1.3 to 4.0; p=0.003). Annulus-indexed MV tenting area showed only a tendency towards primary study endpoint prediction (HR 2.8; 95% CI 0.6 to 12.6; p=0.17). Between female and male patients, BSA-indexed MV tenting area was similar (1.42±0.4 cm2/m2 vs 1.45±0.4cm2/cm2; p=0.6) and gender was not associated with primary study outcome (HR 0.8; 95% CI 0.5 to 1.4; p=0.5).ConclusionIn our FMR cohort, BSA-indexed MV tenting area showed the strongest association with negative outcomes following isolated MV annuloplasty. Patients with BSA-indexed MV tenting area >1.35cm2/m2 could potentially benefit from additional surgical maneuvers addressing left ventricular remodelling.

Comparison of bicuspid and tricuspid aortic valve repair

OBJECTIVES The aim of this study was to compare the outcomes of tricuspid aortic valve (TAV) and bicuspid aortic valve (BAV) repair. METHODS We assessed mortality, freedom from reoperation and the rate of aortic valve regurgitation recurrence. Mortality in both groups was compared with expected survival, and risk factors for reoperation were identified. RESULTS From January 2010 to April 2020, a total of 368 elective aortic valve repair procedures were performed, including 223 (60.6%) in patients with TAV. The perioperative mortality was 0.7% in the BAV group and 3.6% in the TAV group (P = 0.079). Estimated survival at 5 years in the BAV versus TAV group was 97 ± 3% vs 80 ± 6%, respectively (P &lt; 0.001). Freedom from reoperation at 5 years in the TAV versus BAV group was 96 ± 3% vs 93 ± 4%, respectively (P = 0.28). Grade 2 or more aortic valve regurgitation was noted in 9.9% of BAV patients and 11% of TAV patients (P = 0.66). Reoperation was predicted by cusp perforation [hazard ratio 15.86 (4.44–56.61); P &lt; 0.001], the use of pericardial patch [hazard ratio 8.58 (1.96–37.53); P = 0.004] and aortic valve annulus diameter &gt;27.5 mm [hazard ratio 3.07 (0.99–9.58); P = 0.053]. CONCLUSIONS BAV repair is as durable as TAV repair. BAV is not a predictor of a higher rate of reoperations. BAV repair yields survival comparable to expected. Cusp perforation, aortic valve annulus diameter &gt;27.5 mm and the use of pericardial patch adversely impact long-term outcome of aortic valve repair.

Evolution from mitral annular dysfunction to severe mitral regurgitation in Barlow’s disease

OBJECTIVES Barlow’s disease (BD) is characterized by thick, redundant mitral valve (MV) leaflets, which can lead to prolapse and significant mitral regurgitation (MR). MV annular abnormalities are also commonly observed and increasingly recognized as possible primary pathology, with leaflet thickening being secondary to increased stress on the MV apparatus. To provide more insights into this hypothesis, the evolution of MV abnormalities over time in patients with BD was assessed. METHODS A total of 64 patients (54 ± 12 years, 72% male) with BD who underwent MV surgery and had multiple transthoracic echocardiograms (TTE) before surgery were included. In total, 186 TTE were analysed (median time interval 4.2, interquartile range 2.2–6.5 years) including specific MV characteristics. RESULTS At baseline, MV leaflet length, thickness, billowing height and annular diameter were larger in patients with BD compared to 59 healthy subjects. Systolic outward motion (curling) of the annulus was observed in 77% and severe mitral annular disjunction (≥5 mm) in 38% of patients with BD. Forty (63%) patients had MR grade I–II and 24 (37%) MR grade III–IV; at baseline, the 2 groups only differed in left atrial volume and in thickness and billowing height of the posterior leaflet, showing comparable MV annular abnormalities and dilatation despite different grades of MR. Over time, MV annulus diameter, leaflet length and billowing height increased significantly along with MR grade. CONCLUSIONS In patients with BD, MV annulus abnormalities are present at an early stage and precede the development of significant MR, suggesting their substantial role in the pathophysiology of this disease and as an important target for surgical treatment.

Echocardiographic Follow-Up of Right Ventricular Function After Tetralogy of Fallot Operation

Aim: Although limited in assessing right ventricular (RV) function, echocardiography is widely used after correction for tetralogy of Fallot (TOF). The change in echocardiographic measurements of RV in asymptomatic patients after TOF repair over a long follow-up time is not explored yet. The variation in simple echocardiographic measurements during follow-up of our TOF patients are presented. The predictive value of those parameters in determining a future pulmonary valve replacement is sought. Method: Asymptomatic patients surviving the first year after correction for simple TOF from February 2007 to December 2019 at Başkent University, Istanbul Hospital are enrolled. Patients are followed annually with echocardiography including: RV area, volume, length, RV outflow tract (RVOT) diameter and gradient, tricuspid annulus diameter, tricuspid lateral annular tissue velocities, tricuspid annular plane systolic excursion, TEI index RV ejection fraction (EF) measurements. The change in the consecutive echocardiographic measurements during follow-up is analysed. Patients are evaluated with a cardiac magnetic resonance (CMR) imaging when deemed necessary and compared with echocardiographic measurements. Results: A total of 66 patients (54.5% males) are operated at age 14.4±9.3 months (78.8% with transannular patch). Twelve patients had pulmonary valve replacement (PVR) operation at an age 10.1±3.1 years. During follow-up of 7.2±4.3 years, tricuspid annulus diameter, RV area, RV inlet length, RV volume, RV volume index significantly increased (p=0.001 for all), whereas RV inlet length index, TEI and TEI z score decreased (p<0.0001 for all). When means are compared, tricuspid annulus (28.8mm vs 25.0mm; p=0.013), RV volume (72.2ml vs 52.2ml; p=0.042), RV inlet length index (77.9mm/m2 vs 60.2mm/m2 ; p=0.013), RVOT diameter (28.7 vs 23.0; p=0.007) are increased. RV EF is decreased (51.3% vs 60.5%; p=0.011) in those requiring PVR. Those with higher RV area index, RV volume index, tricuspid annulus diameter and tricuspid annular z score in their first echocardiography after the TOF repair, are more likely to have a PVR operation later on (p<0.05 for all). RV volume index ≥39ml/m2 predicts a PVR within 7 years with 100% sensitivity and 74% specificity. Tricuspid annular z score less than -0.43 seems to eliminate the possibility of having a PVR within 7 years with a sensitivity of 44% and specificity of 100%. Conclusion: Observing the sequential change in echocardiographic parameters like RV volume index, RV area index, tricuspid annulus z score is reliable in determining right ventricular function and can limit the costly CMR applications. Cut off values of RV volume index >39ml/m2 and tricuspid annulus z score ≥ - 0.43 after the initial TOF repair may determine patients with higher possibility of having early PVR and indicate a closer follow-up.

Risk factors and etiology of recurrent mitral regurgitation after edge-to-edge mitral valve repair

Background Recurrent MR has been associated with poor prognosis after transcatheter mitral valve repair (TMVR) with the MitraClip system. However, little is known about risk factors and etiology of recurrent mitral regurgitation (MR) after transcatheter edge-to-edge mitral repair with the MitraClip system. Methods Among consecutive patients who underwent MitraClip for MR from January 2011 to March 2019, we identified 240 patients who had MR ≤2+ at discharge and follow-up echocardiography within three years after the procedure. Recurrent MR was defined as MR ≥3+ during the follow-up period. To investigate the risk factors for recurrent MR, we conducted a Cox proportional hazard model. Results During the follow-up period (median 491 days), 38 patients (15.8%) had recurrent MR (≥3+). The most frequent etiology of recurrent MR was degenerative (n=20, 52.6%), including single leaflet detachment (n=2, 5.3%), loss of leaflet insertion (n=11, 28.9%), and leaflet tear or prolapse (n=7, 18.4%), followed by functional MR (n=18, 47.4%). The risk factors for recurrent MR were greater LV end-diastolic volume (adjusted-HR 1.01, 95% CI 1.00–1.02, p=0.03), higher LV ejection fraction (LVEF) (adjusted-HR 1.05, 95% CI 1.01–1.08, p=0.005), and moderate MR upon discharge (adjusted-HR 2.98, 95% CI 1.50–5.95, p=0.002).After stratification according to the etiology of MR, the association of LVEF was more pronounced in patients with degenerative MR (adjusted-HR 1.07, 95% CI 1.02–1.12, p=0.003), while the association of moderate MR upon discharge was more pronounced in patients with functional MR (adjusted-HR 5.02, 95% CI 1.95–12.8, p&lt;0.001). Furthermore, patients with recurrent MR had an increased antero-posterior annulus diameter regardless of the baseline etiology of the MR. Conclusions Greater LV volume, higher LVEF, and moderate MR at discharge were associated with an increased risk of recurrent MR after the MitraClip procedure. A significant increase of the annulus diameter was observed regardless of the baseline etiology of the MR. Etiology of recurrent MR Funding Acknowledgement Type of funding source: None