Implications of tricuspid regurgitation and right ventricular volume overload in patients with heart failure with preserved ejection fraction.

AIMS: The aim of this study was to assess the pathophysiological implications of severe tricuspid regurgitation (TR) in patients with heart failure with preserved ejection fraction (HFpEF) by using tricuspid transcatheter edge-to-edge repair (T-TEER) as a model of right ventricular (RV) volume overload relief. METHODS AND RESULTS: This prospective interventional single arm trial (NCT04782908) included patients with invasively diagnosed HFpEF. The following parameters were prospectively assessed before and after T-TEER: left ventricular (LV) diastolic properties by invasive pressure-volume loop recordings; biventricular time-volume curves and function as well as septal curvature by cardiac magnetic resonance imaging; strain analyses for timing of septal motion. Overall, 20 patients (median age 78, interquartile range [IQR] 72-83 years, 65% female) were included. T-TEER reduced TR by a median of 2 (of 5) grades (IQR 2-1). T-TEER increased LV stroke volume and LV end-diastolic volume (LVEDV) (p < 0.001), without increasing LV end-diastolic pressure (LVEDP) (p = 0.094), consequently diastolic function improved with a reduction in LVEDP/LVEDV (p = 0.001) and a rightward shift of the end-diastolic pressure-volume relationship. The increase in LVEDV correlated with a decrease in RV end-diastolic volume (p < 0.001) and LV transmural pressure increased (p = 0.028). Secondary to a decrease in early RV filling, improvements in early LV filling were observed, correlating with an alleviation of leftwards bowing of the septum (p < 0.01, respectively). CONCLUSION: Diastolic LV properties in patients with HFpEF and severe TR are importantly determined by ventricular interaction in the setting of RV volume overload. T-TEER reduces RV volume overload and improves biventricular interaction and physiology.

Stressed Blood Volume in Severe Tricuspid Regurgitation: Implications for Transcatheter Treatment.

BACKGROUND: Although tricuspid transcatheter edge-to-edge repair (TEER) has been suggested to improve outcomes in patients with tricuspid regurgitation (TR), patients remain at substantial residual risk after the intervention. Total blood volume is divided between the unstressed volume, filling the vascular space, and stressed blood volume (SBV), generating intravascular pressure. SBV is an important mediator of hemodynamic derangements in heart failure and might pose an attractive adjunctive treatment target. OBJECTIVES: The aim of this study was to investigate the role of SBV in patients with severe TR and its implications for tricuspid TEER. METHODS: In total, 279 patients underwent right heart catheterization prior to TEER. SBV was estimated from hemodynamic variables fit to a comprehensive cardiovascular model. RESULTS: Estimated stressed blood volume (eSBV) was associated with obesity, renal and hepatic dysfunction and cardiac remodeling (P < 0.05 for all). Hemodynamically, eSBV correlated with pulmonary artery and cardiac filling pressures as well as right ventricular-pulmonary artery coupling (P < 0.05 for all). After TEER, patients with eSBV greater than the median demonstrated less reduction in right atrial pressures, peripheral edema, and ascites compared with lower eSBV patients (P < 0.05 for all). Higher eSBV was an independent predictor of the occurrence of death and heart failure hospitalization during a median follow-up duration of 618 days (P < 0.05 for all). CONCLUSIONS: In patients with severe TR, eSBV is associated with obesity, renal and liver dysfunction, more severe heart failure, attenuated reduction of venous congestion after TEER, and adverse clinical outcomes. Estimation of SBV should be incorporated in future trials in the field to identify patients in need of adjunctive therapies.

Short-Term Effects of Different Transcatheter Edge-to-Edge Devices on Mitral Valve Geometry.

Background Short-term effects on mitral valve (MV) anatomy after transcatheter edge-to-edge repair using the PASCAL system remain unknown. Precise quantification might allow for an advanced analysis of predictors for mean transmitral gradients. Methods and Results Consecutive patients undergoing transcatheter edge-to-edge repair for secondary mitral regurgitation using PASCAL or MitraClip systems were included. Quantification of short-term MV changes throughout the cardiac cycle was performed using peri-interventional 3-dimensional MV images. Predictors for mean transmitral gradients were identified in univariable and multivariable regression analysis. Long-term results were described during 1-year follow-up. A total of 100 patients undergoing transcatheter edge-to-edge repair using PASCAL (n=50) or MitraClip systems (n=50) were included. Significant reductions of anterior-posterior diameter, annular circumference, and area throughout the cardiac cycle were found in both cohorts (P<0.05 for all). Anatomic MV orifice area remained larger in the PASCAL cohort in mid (2.8±1.0 versus 2.4±0.9 cm2; P=0.049) and late diastole (2.7±1.1 versus 2.2±0.8 cm2; P=0.036) compared with the MitraClip cohort. Besides a device-specific profile of independent predictor of mean transmitral gradients, reduction of middiastolic anatomic MV orifice area was identified as an independent predictor in both the PASCAL (ß=-0.410; P=0.001) and MitraClip cohorts (ß=-0.318; P=0.028). At follow-up, reduction of mitral regurgitation grade to mild or less was more durable in the PASCAL cohort (90% versus 72%; P=0.035). Conclusions PASCAL and MitraClip showed comparable short-term effects on MV geometry. However, PASCAL might better preserve MV function and demonstrated more durable mitral regurgitation reduction during follow-up. Identification of independent predictors for mean transmitral gradients might potentially help to guide device selection in the future.

Fate of iatrogenic atrial septal defects following mitral transcatheter edge-to-edge repair - a subanalysis of the MITHRAS trial.

Persisting iatrogenic atrial septal defects (iASD) after transcatheter mitral edge-to-edge repair (M-TEER) are associated with impaired outcomes. We investigated the natural history of relevant iASDs with left-to-right shunting post-M-TEER, predictors of spontaneous closure of iASD between 1 and 6 months post-M-TEER, and outcomes (heart failure [HF] hospitalization) in patients with spontaneous closure versus those with persistent iASD 6 months post-M-TEER. Patients with a relevant iASD 1-month post-M-TEER, who were treated conservatively in the randomized controlled MITHRAS trial, underwent clinical follow-up including transesophageal echocardiography 6 months post-M-TEER. Overall, 36 patients (median 77 [interquartile range 65-81] years; 36% women) completed the 6-months follow-up. Six (17%) patients had a spontaneous closure of the iASD. The eccentricity index of the iASD 1-month after M-TEER was the strongest predictor for spontaneous closure (Odds ratio 3.78; 95% confidence interval 1.26-11.33, p = 0.01) and an eccentricity index of < 1.9 provided a sensitivity of 77% at a specificity of 83% for iASD persistence (Area under the curve 0.83, p < 0.001) within 6-months post M-TEER.At follow-up, a numerical difference in the endpoint of HF hospitalization between the spontaneous closure and the residual shunt group (0% vs. 20%, p = 0.25) was observed. The eccentricity of the iASD was the strongest predictor for spontaneous closure at 1-months and an eccentricity index of < 1.9 is associated with a high persistence rate for 6 month after M-TEER. Clinical Trial Registration ClinicalTrials.gov https://clinicaltrials.gov/ct2/show/NCT03024268 Identifier: NCT03024268. a (red) is reflecting the mayor lengthwise dimension and b (blue) the mayor oblique dimension. The eccentricity index is calculated by dividing a through b. (Open circle) is depicting an example for a round iASD and (Open rhombus) an example for an eccentric iASD 1 month after M-TEER.

Iatrogenic Atrial Septal Defects Following Transcatheter Mitral Valve Repair and Implications of Interventional Closure.

OBJECTIVES: The authors investigated whether iatrogenic atrial septal defect (iASD) closure post-transcatheter mitral valve edge-to-edge repair (TMVR) is superior to conservative therapy (CT) and whether outcomes (death/heart failure [HF] hospitalization) differ between patients with and without an iASD post-TMVR. BACKGROUND: Transseptal access for TMVR can create an iASD, which is associated with impaired outcomes. Controversially, the creation of an iASD in HF has been linked to improved hemodynamics. METHODS: 80 patients with an iASD and relevant left-to-right shunting (Qp:Qs ≥1.3) 30 days following TMVR were randomized to CT or interventional closure of the iASD (MITHRAS [Closure of Iatrogenic Atrial Septal Defect Following Transcatheter Mitral Valve Repair] cohort), and 235 patients without an iASD served as a comparative cohort. RESULTS: All patients of the MITHRAS cohort (mean age 77 ± 9 years, 39% women) received their allocated treatment, and follow-up was completed for all MITHRAS and comparative cohort (mean age 77 ± 8 years, 47% women) patients. Twelve months post-TMVR, there was no significant difference in the combined endpoint of death or HF hospitalization within the MITHRAS cohort (iASD closure: 35% vs CT 50%; P = 0.26). The combined endpoint was more frequent among patients within the MITHRAS cohort as opposed to the comparative cohort (43% vs 17%; P < 0.0001), primarily driven by a higher rate of HF hospitalization (34% vs 8%; P = 0.004). CONCLUSIONS: In this randomized controlled trial, interventional closure of a relevant iASD 1 month after TMVR did not result in improved clinical outcomes at 12 months post-TMVR. Patients with an iASD are at higher risk for HF hospitalization independent of iASD management and warrant close follow-up. (Closure of Iatrogenic Atrial Septal Defect Following Transcatheter Mitral Valve Repair [MITHRAS]; NCT03024268).

Biventricular Physiology of Iatrogenic Atrial Septal Defects Following Transcatheter Mitral Valve Edge-to-Edge Repair.

OBJECTIVES: The study sought to assess the acute hemodynamic effects of iatrogenic atrial septal defect (iASD) closure following transcatheter mitral valve edge-to-edge repair (TMVR). BACKGROUND: The potential hemodynamic and clinical consequences of an iASD following TMVR are currently subject to controversial debates. METHODS: In 21 patients with relevant left-to-right shunt flow (50% [IQR: 38% to 60%] of systemic perfusion volume) across an iASD following TMVR, interventional closure was performed with recordings of left ventricular (LV) and right ventricular (RV) pressure-volume loops during iASD occlusion. RESULTS: iASD occlusion led to a volume shift from the RV (RV end-diastolic volume index: pre 102 [IQR: 80 to 120] ml/m2, post 92 [IQR: 70 to 111] ml/m2; p < 0.001) to the LV (LV end-diastolic volume index: pre 91 [IQR: 74 to 124] ml/m2, post 97 [IQR: 77 to 127] ml/m2; p < 0.001) with reduced RV (3.49 [IQR: 2.07 to 3.58] l/min/m2 vs. 2.68 [IQR: 2.07 to 3.58] l/min/m2; p < 0.001) but increased LV cardiac index (2.25 [IQR: 1.80 to 3.28] l/min/m2 vs. 2.77 [IQR: 1.90 to 3.34] l/min/m2; p = 0.039). Although RV end-diastolic pressure decreased (pre 5.0 [IQR: 4.0 to 8.5] mm Hg, post 4.5 [IQR: 3.0 to 8.3] mm Hg; p = 0.024), LV end-diastolic pressure remained unchanged (pre 11.0 [IQR: 9.5 to 14.0] mm Hg, post 13.0 [IQR: 9.0 to 15.5] mm Hg; p = 0.142). LV transmural pressure increased (7.0 [IQR: 4.0 to 11.0] mm Hg vs. 11.0 [IQR: 7.0 to 15.0] mm Hg; p = 0.001) and LV eccentricity index decreased (p < 0.001). The change in LV transmural pressure correlated significantly with the change in LV-to-RV end-diastolic volume ratio (r = 0.674; p = 0.018). Right heart failure symptoms declined at 1-month follow-up (71% vs. 35%; p = 0.003) as did New York Heart Association functional class (≥III: 48% vs. 25%; p < 0.001). CONCLUSIONS: iASD closure following TMVR leads to a volume shift from the RV to the LV with reduced pulmonary but increased systemic cardiac index and with favorable biventricular interaction at maintained LV filling pressure, resulting in a decline in heart failure symptoms at 1-month follow-up.

Physiologic effects and functional outcome after treatment of dysfunctional right ventricular outflow tract in congenital heart disease using a two-stage intervention.

BACKGROUND: Pathophysiological differences in relief of pulmonary stenosis (PS) as opposed to pulmonary regurgitation (PR) by percutaneous pulmonary valve implantation (PPVI) remain elusive, but might impact current assessment of procedural success and ultimately indications. METHODS: Invasive pressure measurements, cardiac magnetic resonance imaging and cardiopulmonary exercise testing were performed before pre-stenting (BMS), after BMS and after PPVI in patients with either PS or PR. RESULTS: In PS (n = 14), BMS reduced the right ventricular (RV) to systemic pressure ratio (0.8 ± 0.2 vs. 0.4 ± 0.1%; p < .01), improved RF EF (53 ± 14 vs. 59 ± 12%; p = .01) but introduced free PR (PR fraction post 39 ± 12%; p < .01) with no changes in effective RV stroke volume (SV). PPVI eliminated PR (PR fraction 5 ± 3%; p < .01) and improved effective RV SV (p < .01) with no changes in RV EF (p = .47). Peak VO2 improved significantly after BMS, with no changes following PPVI (26 ± 9 vs. 30 ± 11 vs. 31 ± 10 ml/kg*min). In PR (n = 14), BMS exaggerated PR (PR fraction post 47 ± 10) with reduction in effective RV SV (pre 43 ± 9 vs. post 38 ± 8 ml/m2; p = .01), which improved after PPVI (post PPVI 49 ± 9 ml/m2; p < .01), secondary to elimination of PR (PR fraction 5 ± 4%; p < .01). RV EF (pre 53 ± 11 vs. post 53 ± 9 vs. post PPVI 50 ± 9%) and Peak VO2 (pre 22 ± 7 vs. post 21 ± 7 vs. post PPVI 23 ± 7 ml/kg*min) remained unchanged. CONCLUSIONS: Exercise capacity in patients with right ventricular outflow tract dysfunction is primarily afterload-dependent.

Implications of atrial volumes in surgical corrected Tetralogy of Fallot on clinical adverse events.

BACKGROUND: While left atrial (LA) size has been shown as a strong predictor of cardiovascular diseases in various studies, the role of right atrial (RA) enlargement, especially in the growing population of patients with congenital heart diseases (CHD) is largely unknown. We sought to evaluate (1) RA and LA volumes in patients with repaired Tetralogy of Fallot (TOF) and assess correlations to (2) functional parameters and (3) clinical adverse events. METHODS: 169 patients with repaired TOF were enrolled following a targeted protocol for Cardiovascular magnetic resonance imaging (CMR), Cardiopulmonary exercise tests (CPET), Echocardiography and Measurement of NT-proBNP. Clinical history was assessed at enrollment and during a median Follow-up of 23 months (IQR 9-40). The primary clinical endpoint was a composite of all cause mortality, aborted sudden cardiac death and sustained VT. Prespecified secondary surrogate endpoint included worsening heart failure (NYHA III-IV), non-sustained VT and sustained supraventricular tachycardia. RESULTS: RA Systolic indexed volume (RASVi) correlated with LA Systolic indexed volume (LASVi) (r = 0.59, p < 0.001) and both correlated with the patient age (r = 0.52, p < 0.001; r = 0.59, p < 0.001 respectively). Patients in the upper tertil of RASVi (>58 ml/m2) had higher NT-proBNP levels, longer QRS duration, larger ventricle diameters, higher RV mass and lower peak oxygen uptake. RASVi was associated with the primary composite adverse event at univariate Cox-regression analysis (HR: 1.044, CI: 1.008-1.08, p = 0.01). Bayesian Multivariate model averaging revealed RASVi as predictor of secondary surrogate adverse outcome (HR: 1.06, CI: 1.053-1.068, Pb = 0,889). CONCLUSION: Among patients with repaired TOF, RA dilatation is an independent predictor for adverse clinical events. As such, routine assessment of RA volumes could be useful to further improve decision-making and management of these patients in the future.

Fatal Erosion Atrial Septal Defect Device.

Percutaneus device closure of atrial septal defects offers an alternative to conventional surgical repair. While procedure techniques and devices have improved, severe complications remain that are neither completely understood nor entire predictable. We present a case of a 19-year-old female with left atrial erosion leading to lethal pericardial tamponade 1 month after ASD II closure using the Nit Occlude ASD-R® (NOASD-R, pfm Medical, Cologne, Germany). To our knowledge this is the first reported lethal complication related to this device.