Left ventricular outflow tract area after percutaneous transseptal transcatheter mitral valve implantation: A three-dimensional transesophageal echocardiography study.

BACKGROUND: Left ventricular (LV) outflow tract (LVOT) obstruction increases mortality in patients undergoing transcatheter mitral valve implantation (TMVI) in degenerated bioprostheses, annuloplasty rings, and native mitral valves. We aimed to evaluate the LVOT area after TMVI using 3-dimensional (3D) transesophageal echocardiography (TEE) and to investigate the preprocedural cardiac geometry that affects the LVOT area after TMVI. METHODS: We retrospectively reviewed echocardiography data in 43 patients who had TMVI. A change in pressure gradient across LVOT from before to after TMVI (∆PG) and postprocedure 3D LVOT cross-sectional area at the level of the most distal portion of the mitral valve stent that was closest to the LV apex were assessed as evidence of LVOT narrowing. RESULTS: Transcatheter mitral valve implantation with the use of balloon-expandable valve system was performed for 24 bioprostheses, 7 annuloplasty rings, and 12 native valves. Compared to patients without increase in LVOT gradient (∆PG <10 mm Hg; n = 33), patients with increase in LVOT gradient (∆PG ≥10 mm Hg; n = 10) had smaller LV end-systolic volume (LVESV), greater LV ejection fraction (LVEF), and smaller aorto-mitral (AM) angle. The LVOT area at the valve stent distal edge showed strong association with ∆PG (r = -.68, P < .0001). Only a small AM angle was associated with a small LVOT area at the valve stent distal edge on multivariable analysis, independent of LVESV and LVEF. CONCLUSION: Small LV size, preserved LVEF, and small AM angle were associated with LVOT narrowing. 3D-derived AM angle might be independently associated with LVOT narrowing in patients undergoing transcatheter mitral valve-in-valve, valve-in-ring, and valve-in-native valve implantation, independent of LVESV and LVEF.

Impact of Percutaneous Edge-to-Edge Repair in Patients With Atrial Functional Mitral Regurgitation.

BACKGROUND: The aim of this study was to clarify the clinical outcomes of patients with atrial functional mitral regurgitation (FMR) who underwent the MitraClip procedure compared with those with conventional FMR and sinus rhythm (SR).Methods and Results:Of 303 patients with FMR who underwent the MitraClip procedure, 40 with "atrial-FMR" defined as FMR with permanent atrial fibrillation and normal left ventricular (LV) function/size and 115 with "sinus-FMR" defined as FMR with SR and LV dysfunction were reviewed. Transthoracic and 3D transesophageal echocardiography, and the cardiac complication rate (composite of all-cause death, heart failure admission, mitral valve (MV) surgery, and redo MitraClip procedure) during the 12-month follow-up were compared between the groups. After the MitraClip procedure, reductions in the mitral annular area and its anteroposterior dimension and in the leaflet closure area were observed in both groups. MV orifice area was smaller with greater transmitral pressure gradient (P<0.05) after the procedure in atrial-FMR patients than in those with sinus-FMR. The prevalence of residual MR was similar, but significant tricuspid regurgitation (TR) was more prevalent in the atrial-FMR group at follow-up. Cardiac complication rate was comparable between groups (20% vs. 25%, P=0.63). CONCLUSIONS: Reduction of MR occurred in atrial-FMR probably because of the increase in leaflet coaptation area. Significant TR was more common after the MitraClip procedure in patients with atrial-FMR than with sinus-FMR. However, mid-term outcomes were comparable between patients with atrial-FMR and sinus-FMR.

An association between right ventricular dysfunction and sudden cardiac death.

BACKGROUND: The effectiveness of severely reduced left ventricular ejection fraction (LVEF <35%) as a predictor of sudden cardiac death (SCD) has diminished, and improvements in risk stratification await discovery of novel markers. Right ventricular (RV) abnormalities can be observed in conditions such as chronic obstructive pulmonary disease and sleep apnea, which have been linked to SCD. OBJECTIVE: The purpose of this study was to evaluate whether RV abnormalities were associated with SCD after accounting for LVEF and other patient characteristics. METHODS: In a large, prospective ongoing community-based study of SCD in the Portland, Oregon, metropolitan area, SCD cases (age ≥18 years; 2002-2014) were compared to controls with coronary artery disease but no SCD. Using a novel archive of digital echocardiograms, a standardized approach was used to evaluate RV basal diameter, RV end-diastolic area, and right ventricular fractional area change (RVFAC). RESULTS: A total of 350 subjects were studied, including 81 SCD cases (age 68.7 ± 13.6 years; 73% male) and 269 controls (age 66.5 ± 10.2 years; 69% male). In multivariate analysis, RVFAC was significantly associated with SCD (odds ratio 1.14 for each 5% decrease; 95% confidence interval 1.03-1.25; P = .01). When modeled with LVEF ≤35%, RVFAC ≤35% was significantly associated with increased risk of SCD. Individuals with both left ventricular and RV dysfunction had a 3× higher odds of SCD than those with neither (odds ratio 3.19; 95% confidence interval 1.33-7.68; P = .01). CONCLUSION: RV dysfunction was associated with a significantly increased risk of SCD independent of LVEF and, when combined with LVEF, had additive effects on SCD risk.

Predictors and Outcomes of Persistent Tricuspid Regurgitation After Transcatheter Aortic Valve Implantation.

Persistent tricuspid regurgitation (TR) after transcatheter aortic valve implantation (TAVI) has been reported to increase mortality. The aim of this study was to investigate clinical and echocardiographic determinants and outcome of persistent TR after TAVI. We reviewed 1,085 patients who underwent TAVI. Among them, 100 patients who had ≥moderate TR without organic dysfunction of the tricuspid valve apparatus were studied. Preprocedural and follow-up transthoracic echocardiography after TAVI were analyzed. After TAVI, patients were divided into persistent TR group and improved TR group. Clinical event was defined as all-cause mortality and readmission for heart failure within 1,000 days. Fifty-three (53%) patients had persistent TR, whereas 47 (47%) patients had improved TR. Risk of clinical event was significantly higher in the persistent TR group compared with the improved TR group. Atrial fibrillation (AF) and tricuspid annular dimension (TAD; p <0.05 for all) were independent predictors of persistent TR. Receiver operating characteristic curve showed the optimal cut-off value of TAD for predicting persistent TR was 37 mm. The combination of AF and TAD ≥37 mm was associated with persistent TR (p <0.001). In conclusion, AF and dilated TAD before TAVI predicted persistent TR which was associated with higher all-cause mortality and readmission for heart failure.

Usefulness of Intraprocedural Pulmonary Venous Flow for Predicting Recurrent Mitral Regurgitation and Clinical Outcomes After Percutaneous Mitral Valve Repair With the MitraClip.

OBJECTIVES: The aim of this study was to determine the prognostic value of pulmonary venous (PV) flow during MitraClip implantation. BACKGROUND: The clinical significance of PV flow information during MitraClip implantation is unknown. METHODS: A total of 300 patients who underwent MitraClip implantation and in whom the measurement of PV flow was completed using intraprocedural transesophageal echocardiography were retrospectively reviewed. The optimal threshold of the ratio of systolic velocity-time integral (Svti) to diastolic velocity-time integral (Dvti) ratio after MitraClip placement for major adverse cardiovascular events (all-cause death, redo MitraClip implantation, mitral valve surgery, and heart transplantation) during 12 months was assessed. The best cutoff ratio was 0.72. Patients were divided into 2 groups using this cutoff ratio (low Svti/Dvti, n = 91; high Svti/Dvti, n = 209). RESULTS: Following mitral regurgitation reduction by MitraClip placement, Svti increased in the both groups. The frequency of mitral regurgitation 3/4+ immediately after MitraClip implantation, at 1-month follow-up, and at 12-month follow-up was significantly higher in patients with low Svti/Dvti ratios than in those with high Svti/Dvti ratios (after MitraClip placement, 5.5% vs. 0%; p < 0.001; at 1 month; 26% vs. 5.2%; p < 0.001; at 12 months, 18% vs. 5.3%; p = 0.006). Major adverse cardiovascular events during 12 months were significantly higher in patients with low Svti/Dvti ratios than in those with high Svti/Dvti ratios (23% vs. 6.2%; p < 0.001). Multivariate analysis demonstrated that low Svti/Dvti ratio was significantly associated with major adverse cardiovascular events during 12 months after adjustment for age, baseline renal function, and mean transmitral pressure gradient (adjusted hazard ratio: 4.00; 95% confidence interval: 2.02 to 8.23; p < 0.001). CONCLUSIONS: PV flow information in the catheterization laboratory immediately after MitraClip implantation predicted recurrent mitral regurgitation and worse long-term outcomes.

Left atrial pressure is associated with iatrogenic atrial septal defect after mitral valve clip.

OBJECTIVES: Mitral valve (MV) clip procedure requires interatrial trans-septal puncture to access the left atrium (LA). Iatrogenic atrial septal defect (iASD) is not uncommon and may remain for a while. However, haemodynamic and echocardiographic determinants of persistent iASD are not well investigated. We sought to find haemodynamic and echocardiographic determinants of iASD after MV clip. METHODS: A total of 131 patients with grades 3 to 4+ mitral regurgitation who underwent MitraClip and completed invasive haemodynamic measurement, baseline, 1 month and approximately 12 months of transthoracic echocardiography (TTE) follow-up were retrospectively reviewed. RESULTS: TTE at 1 month showed persistent iASD in 57% (1M-iASD). Mean LA pressure after clip was significantly higher in patients with 1M-iASD than patients without 1M-iASD (17±6 mm Hg vs 15±5 mm Hg, p=0.01). Among patients with 1M-iASD, 24 patients (35%) had persistent iASD at 12 months (12M-iASD). Mean LA pressure after clip was significantly higher in patients with 12M-iASD than patients without 12M-iASD (19±6 mm Hg vs 16±6 mm Hg, p=0.04). Patients with 12M-iASD did not significantly differ from patients without 12M-iASD in terms of right heart enlargement, estimated systolic pulmonary artery pressure, New York Heart Association functional class and brain natriuretic peptide at 12 months. Logistic regression analysis, however, showed that mean LA pressure after clip was significantly associated with persistent iASD at 12 months in patients with 1M-iASD even after adjustment for cardiac index after clip and the prevalence of mitral regurgitation ≥3+ at 12 months (OR 1.10 per 1 mm Hg, 95% CI 1.01 to 1.21, p=0.04). CONCLUSIONS: Elevated LA pressure after MV clip was associated with persistent iASD.

Relation Between Pulmonary Venous Flow and Left Atrial Pressure During Percutaneous Mitral Valve Repair With the MitraClip.

Pulmonary venous (PV) flow may provide valuable information in terms of the severity of mitral regurgitation and left atrial (LA) pressure. We sought to find PV flow determinants of LA pressure during MitraClip procedure. We analyzed 575 PV flows in 290 patients using transesophageal echocardiography before and after MitraClip procedure. We measured peak systolic velocity (Sv), diastolic velocity (Dv), systolic velocity time integral (Svti), diastolic velocity time integral (Dvti), and those systolic to diastolic ratio as PV flow parameters. Systolic PV flow velocity was lower than diastolic PV flow velocity before the procedure, but systolic PV flow velocity markedly increased after the procedure. Peak Sv/Dv ratio and Svti/Dvti ratio after the procedure were significantly higher than those before the procedure (peak Sv/Dv; 1.06 [inter-quartile range (IQR) 0.73 to 1.34] vs 0.32 [IQR 0.03 to 0.55], p <0.001, Svti/Dvti; 1.06 [IQR 0.76 to 1.61] vs 0.26 [IQR 0.02 to 0.51], p <0.001). Peak Sv/Dv ratio and Svti/Dvti ratio were negatively correlated with mean LA pressure and LA pressure V wave, respectively (peak Sv/Dv ratio; r = -0.50 and r = -0.59, Svti/Dvti ratio; r = -0.47 and r = -0.58, p <0.001). In receiver operating characteristics curve assessing the ability of PV flow to predict mean LA pressure ≥20 mm Hg after the successful procedure, the area under the curve of peak Sv/Dv ratio was 0.76 (p <0.001). Peak Sv/Dv ratio <0.98 best predicted LA pressure ≥20 mm Hg with 77% sensitivity and 71% specificity. In conclusion, systolic PV flow velocity immediately increased in response to mitral regurgitation reduction during MitraClip procedure. PV flow velocity, specifically systolic to diastolic ratio, was useful to evaluate invasively determined LA pressure.