Durable Robotic Mitral Repair of Degenerative Primary Regurgitation With Long-Term Follow-Up.

BACKGROUND: Variation in degenerative mitral morphology may contribute to suboptimal repair rates. This study evaluates outcomes of a standardized mitral repair technique. METHODS: An institutional clinical registry was used to identify 1036 consecutive patients undergoing robotic mitral surgery between 2005 and 2020: 87% (n = 902) had degenerative disease. Calcification, failed transcatheter repair, and endocarditis were excluded, leaving 582 (68%) patients with isolated posterior leaflet and 268 (32%) with anterior or bileaflet prolapse. Standardized repair comprised triangular resection and true-sized flexible band in posterior leaflet prolapse. Freedom from greater than 2+ moderate mitral regurgitation stratified by prolapse location was assessed using competing risk analysis with death as a competing event. Median follow-up was 5.5 (range 0-15) years. RESULTS: Of patients with isolated posterior leaflet prolapse, 87% (n = 506) had standardized repairs and 13% (n = 76) had additional or nonresectional techniques vs 24% (n = 65) and 76% (n = 203), respectively, for anterior or bileaflet prolapse (P < .001). Adjunctive techniques in the isolated posterior leaflet group included chordal reconstruction (8.6%, n = 50) and commissural sutures (3.4%, n = 20). Overall, median clamp time was 80 (interquartile range, 68-98) minutes, 17 patients required intraoperative re-repair, and 6 required mitral replacement. Freedom from greater than 2+ regurgitation or reintervention at 10 years was 92% for posterior prolapse (vs 83% for anterior or bileaflet prolapse). Anterior or bileaflet prolapse was associated with late greater than 2+ regurgitation (hazard ratio, 3.0; 95% confidence interval, 1.3-7.0). CONCLUSIONS: Posterior leaflet prolapse may be repaired in greater than 99% of patients using triangular resection and band annuloplasty, with satisfactory long-term durability. Increased risk of complex repairs and inferior durability highlights the value of identifying anterior and bileaflet prolapse preoperatively.

Right-to-Left Shunt Through Iatrogenic Atrial Septal Defect After MitraClip Procedure.

OBJECTIVES: The aim of this study was to investigate the incidence, characteristics, hemodynamic conditions, and clinical significance of right-to-left (R-L) shunt through an iatrogenic atrial septal defect (iASD) after the MitraClip procedure. BACKGROUND: R-L shunt through an iASD after the MitraClip procedure has not been well investigated. METHODS: From 2014 to 2017, 385 consecutive patients with mitral regurgitation underwent the MitraClip procedure. iASD was assessed using intraprocedural transesophageal echocardiography. Right and left heart catheterization was used to assess the hemodynamic status of patients. All patients provided written informed consent for the procedure. All data for this study were collected from an established interventional cardiology laboratory database approved by the Cedars-Sinai Medical Center Institutional Review Board. RESULTS: R-L shunt was observed in 20 patients (5%). In 7 of these patients (35%), R-L shunt was accompanied by acute deoxygenation. Prevalence of severe tricuspid regurgitation (55% vs. 20%; p = 0.001), serum B-type natriuretic peptide (664 pg/ml [434 to 1,169 pg/ml] vs. 400 pg/ml [195 to 699 pg/ml]; p = 0.006), mean pulmonary artery pressure (38 mm Hg [34 to 45 mm Hg] vs. 29 mm Hg [22 to 37 mm Hg]; p < 0.001), and right atrial pressure (19 mm Hg [13 to 20 mm Hg] vs. 10 mm Hg [7 to 14 mm Hg]; p < 0.001) were significantly higher in patients with R-L shunt than in those with left-to-right shunt. Patients with R-L shunt also showed a more prominent reduction in the left atrial V-wave and mean pressure from baseline to post-procedure compared with those with left-to-right shunt (-22.8 ± 2.6 mm Hg vs. -11.8 ± 0.9 mm Hg [p = 0.002] and -7.9 ± 0.8 mm Hg vs. -4.0 ± 0.4 mm Hg [p = 0.003], respectively). CONCLUSIONS: R-L shunt through an iASD was observed in 5% of patients who underwent the MitraClip procedure and in one-third of patients with R-L shunt presented acute deoxygenation. Elevated right atrial pressure concomitant with pulmonary hypertension and significant reduction in left atrial pressure after MitraClip deployment were associated with R-L shunt.

Comparison of mitral valve geometrical effect of percutaneous edge-to-edge repair between central and eccentric functional mitral regurgitation: clinical implications.

AIMS: Percutaneous edge-to-edge repair alters mitral valve (MV) geometry in functional mitral regurgitation (FMR). We sought to characterize MV morphology in patients with central and eccentric FMR, compare the geometrical effect of MitraClip therapy, and elucidate different mechanisms of MR improvement according to FMR subtypes. METHODS AND RESULTS: Seventy-six symptomatic patients with Grade 3 to 4+ FMR (central, n = 39; eccentric, n = 37) underwent three-dimensional transoesophageal echocardiography during MitraClip implantation. We defined procedural success as a reduction of MR by ≥1 grade with having a residual mitral regurgitation (MR) of ≤ grade 2+. Procedural success rate was similar between central and eccentric FMR (77% vs. 78%, P = 0.55). After MitraClip, the reduction in anterior-posterior diameter did not differ between FMR subtypes, but patients with eccentric FMR had a greater reduction in the averaged tethering angle difference (P < 0.001) with less reduction in tenting volume and height (both P < 0.001) than did patients with central FMR. On multivariable analysis, in central FMR, MR reduction post-clip was associated with shortening in anterior-posterior diameter [coefficient 0.388, 95% confidence interval (CI) 0.216-0.561; P < 0.001] and an increase in coaptation area (coefficient 0.117, 95% CI 0.039-0.194; P = 0.004), whereas in eccentric FMR MR reduction was mainly associated with a decrease in the averaged tethering angle difference (coefficient 0.050, 95% CI 0.021-0.078; P = 0.001). CONCLUSION: MV geometrical effect and its association with MR improvement after MitraClip therapy differ according to FMR subtypes. Our results indicate the MR jet direction and the leaflet tethering pattern may be considered in the strategy for percutaneous treatment for FMR.

Relation of Residual Mitral Regurgitation Despite Elevated Mitral Gradients to Risk of Heart Failure Hospitalization After MitraClip Repair.

Achieving minimal residual mitral regurgitation (MR) after percutaneous MitraClip repair is limited by iatrogenic mitral stenosis. It is unknown whether allowing moderately elevated postprocedural mean mitral gradients (MMGs) to achieve < moderate residual MR is preferable to moderate residual regurgitation. Patients with less-than-moderate residual MR but a MMG of ≥5 mm Hg (Group 1) were compared with patients with moderate residual MR (Group 2). The primary end point was heart failure hospitalization. Secondary end points included mortality, subsequent mitral valve surgery, and MR at 1 year. Seventy-eight patients were included in the study. Group 1 included 48 patients (median MMG 6, interquartile range 5-6 mm Hg). Group 2 included 30 patients (median MMG 3.5, interquartile range 2-5 mm Hg). Age, baseline MR severity, and type of MR were not different between groups. Freedom from heart failure hospitalization at 1 year was 91.2 ± 4.2% in Group 1 versus 70.8 ± 8.7% in Group 2 (p = 0.021). Achieved differences in MR reduction between groups persisted at 1 year (p = 0.007). Survival was not different (p = 0.402), and subsequent mitral valve surgery occurred in 4 of 48 (8%) and in 4 of 30 patients (13%) in Group 1 and Group 2, respectively (p = 0.476). By multivariate Cox regression analysis, less-than-moderate residual MR, despite moderately elevated mitral gradients, was associated with a hazard ratio of 0.21 (95% confidence interval 0.04 to 0.96) for subsequent heart failure hospitalization (p = 0.044). In conclusion, patients with less-than-moderate residual MR despite a MMG of ≥5 had a 79% reduction in hazard for subsequent heart failure hospitalization compared with patients with moderate residual MR.

Effect of Percutaneous Edge-to-Edge Repair on Mitral Valve Area and Its Association With Pulmonary Hypertension and Outcomes.

Percutaneous edge-to-edge repair using the MitraClip system causes reduction in mitral valve area (MVA). However, its clinical impact is not fully elucidated. This study assessed the impact of postprocedural MVA reduction on pulmonary hypertension and outcomes. A total of 92 patients with grades 3 to 4 + mitral regurgitation (MR) who underwent MitraClip therapy were retrospectively reviewed. Using intraprocedural, 3-dimensional transesophageal echocardiography, postprocedural MVA was obtained by 2 optimized planes through the medial and lateral orifices of the repaired valve. MVA was reduced by 60.1% immediately after MitraClip procedure (p <0.001). Postprocedural MVA correlated moderately with mean transmitral pressure gradient (TMPG) in the majority of patients (r = -0.56, p <0.001), but discordance of MVA and TMPG was observed in 40% of patients. In multivariable linear regression analysis, postprocedural MVA ≤1.94 cm2 was independently associated with a blunted decrease in systolic pulmonary artery pressure at 1-month follow-up (ß-estimate -4.63, 95% confidence interval -9.71 to -0.15, p = 0.042). Postprocedural MVA ≤1.94 cm2 was an independent predictor of all-cause mortality and heart failure hospitalization after MitraClip (hazard ratio 4.28, 95% confidence interval 1.56 to 11.7, p = 0.005) even after adjustment for age, gender, atrial fibrillation, cause of MR, left ventricular systolic function, pre-existing pulmonary hypertension, and residual MR. After further adjustment for TMPG ≥5 mm Hg, postprocedural MVA ≤1.94 cm2 remained predictive for adverse outcomes (p = 0.048). In conclusion, the intraprocedural assessment of MVA by 3-dimensional transesophageal echocardiography can predict hemodynamic response and postprocedural prognosis after MitraClip therapy.

Impact of Forward Stroke Volume Response on Clinical and Structural Outcomes After Percutaneous Mitral Valve Repair With MitraClip.

BACKGROUND: An increase of systolic forward flow was frequently observed after successful MitraClip implantation in patients with significant mitral regurgitation. However, the impact of systolic forward flow improvement on post-MitraClip outcomes remains unknown. METHODS AND RESULTS: Study population included 160 patients who underwent successful MitraClip implantation. The systolic forward flow was noninvasively calculated as the forward stroke volume (FSV) at baseline before the MitraClip procedure and before discharge with pulse-wave Doppler using transthoracic echocardiography. The optimal threshold of discharge/baseline FSV ratio for 3-year all-cause death was assessed. The best cutoff ratio was 1.09 (9% FSV increase from baseline, P=0.006). The FSV responders were defined as those with >9% increase of FSV from baseline (n=93). From discharge to 12-month follow-up, a significant reduction of LV end-diastolic and end-systolic volumes was observed in the responders, whereas no significant change was observed in the nonresponders. Furthermore, the proportion of New York Heart Association functional class III/IV was significantly lower in the responders at 12 months (2.9% versus 14.6%; P=0.03). Among patients with estimated glomerular filtration rate <60 mL/min per 1.73 m2, estimated glomerular filtration rate was significantly improved at 12 months only in the responders. All-cause mortality at 3 years was significantly lower in the responders than in the nonresponders (17.6% versus 42.3%; P=0.002). Multivariable logistic analysis identified higher baseline FSV, less mitral regurgitation severity, and functional mitral regurgitation as independent predictors of the nonresponders. CONCLUSIONS: FSV increase after MitraClip implantation was associated with more favorable clinical and anatomic outcomes. Severity and pathogenesis of mitral regurgitation and pre-MitraClip FSV predicted postprocedural FSV response.

Incidence, Characteristics, and Clinical Course of Device-Related Thrombus After Watchman Left Atrial Appendage Occlusion Device Implantation in Atrial Fibrillation Patients.

OBJECTIVES: This study investigated characteristics and clinical impact of device-related thrombus formation after Watchman device implantation in atrial fibrillation (AF) patients. BACKGROUND: Left atrial appendage occlusion using the Watchman device is an effective alternative to anticoagulation for stroke prevention in AF patients. However, device-related thrombus formation remains an important concern after Watchman implantation. METHODS: From 2006 to 2014, 119 consecutive AF patients underwent Watchman implantation. Transesophageal echocardiographic (TEE) follow-up was scheduled at 45 days, at 6 months, and at 12 months after the procedure. The incidence, characteristics, and clinical course of device-related thrombus formation detected by TEE were assessed. RESULTS: Follow-up TEE identified thrombus formation on the Watchman device in 4 patients (3.4%). The prevalence of chronic AF was 100% in patients with thrombus, which was higher than that for patients without thrombus (40.0%). Deployed device size was numerically larger in patients with thrombus (29.3 ± 3.8 mm vs. 25.7 ± 3.2 mm, respectively). All patients with thrombus discontinued any of the anticoagulant/antiplatelet therapy which was required under the study protocol. After restarting or continuing warfarin and aspirin therapy, complete resolution of the thrombus was achieved in all patients at subsequent follow-up TEE. Warfarin therapy was discontinued within 6 months for all cases, and there was no thrombus recurrence. The mean follow-up duration was 1,456 ± 546 days, with no death, stroke, or systemic embolization events in patients with thrombus. CONCLUSIONS: AF burden, device size, and anticoagulant/antiplatelet regimens can be associated with device-related thrombus after Watchman device implantation. Short-term warfarin therapy was effective, and the clinical outcomes were favorable.

Mitral annular calcification is not associated with decreased procedural success, durability of repair, or left ventricular remodelling in percutaneous edge-to-edge repair of mitral regurgitation.

AIMS: Mitral annular calcification (MAC) negatively influences outcomes in surgical mitral valve (MV) repair for mitral regurgitation (MR). However, there are no data on whether MAC impacts on outcomes of MitraClip percutaneous MV edge-to-edge repair. This study sought to investigate whether the presence of MAC impacts on the procedural success and durability of percutaneous transcatheter repair of MR using the MitraClip. METHODS AND RESULTS: One hundred and seventy-three patients undergoing MitraClip repair for significant MR were studied. Patients with moderate-or-severe MAC (n=28) were compared to those with no-or-mild MAC. Post-procedural MR severity was not different (p=0.642) and MR reduction to moderate-or-less was equally high in patients with moderate-or-severe MAC (100%) and those without (96.7%), p=1.000. At one year, MR severity was not different (p=0.831), and there was no difference in the repair durability when comparing patients with moderate-or-severe MAC (93.8%) to those without (90.6%), p=1.000. All patients with moderate-or-severe MAC assessed at one year were in NYHA functional Class I-II and had haemodynamic improvements with a decrease in pulmonary artery systolic pressure (-6.5±13.1 mmHg), p=0.021, and end-diastolic left ventricular internal diameter (-3.9±6.5 mm), p=0.034, not different to those achieved by patients without MAC (both p>0.100). CONCLUSIONS: Moderate-or-severe MAC scored by echocardiography and confirmed on fluoroscopy was not associated with decreased procedural success or durability of repair. Patients with moderate-or-severe MAC had improvements in clinical symptoms and haemodynamics, as well as decreased left ventricular dimensions.

Transcatheter Procedure for Residual Mitral Regurgitation After MitraClip Implantation Using Amplatzer Duct Occluder II.

OBJECTIVES: This study reports a novel transcatheter procedure for residual mitral regurgitation (MR) after MitraClip implantation using the Amplatzer Duct Occluder II (ADO II). BACKGROUND: Although the MitraClip procedure is a transcatheter treatment option for patients at high surgical risk with severe MR, management of significant residual MR after MitraClip implantation is still challenging. METHODS: We describe a case series of 9 consecutive patients who underwent transcatheter deployment of the ADO II plug for significant residual MR after MitraClip implantation from April to October 2015. RESULTS: The mean age was 79.3 ± 11.4 years. The deployment of the ADO II plug was performed at the initial MitraClip procedure in 7 patients and at the second procedure for recurrent symptoms in 2 patients. There were 2 types of residual MR seen after MitraClip implantation: residual commissural MR (n = 3) and residual intraclip MR (n = 6). The ADO II was successfully deployed with significant reduction of MR flow and left atrial pressure in all patients. The ADO II plug was retrieved in 1 patient because of device embolization to the ostial right coronary artery. However, all patients were discharged 1.8 ± 1.2 days after the procedure, with no significant MR on pre-discharge transthoracic echocardiography. In 8 patients who underwent 1-month symptomatic assessment, clinical symptoms were diminished to New York Heart Association functional class I or II. CONCLUSIONS: Transcatheter deployment of the ADO II plug was effective for the reduction of residual commissural MR and intraclip MR after MitraClip implantation. The potential role of this technique should be established for challenging cases.

Impact of pulmonary hypertension on outcomes in patients with functional mitral regurgitation undergoing percutaneous edge-to-edge repair.

Preexisting pulmonary hypertension (PH) is associated with poor outcomes after surgical mitral valve repair for functional mitral regurgitation (FMR). However its clinical impact on MitraClip therapy remains unknown. The aim of this study was therefore to evaluate the impact of preexisting PH on MitraClip therapy for patients with FMR. Ninety-one consecutive patients who had FMR and who underwent the MitraClip procedure were studied. They were divided into 2 groups on the basis of pulmonary artery systolic pressure: the PH group (n = 48) and the non-PH group (n = 43). PH was defined as pulmonary artery systolic pressure >50 mm Hg using Doppler echocardiography. Procedural success (defined as magnetic resonance reduction to grade 2+ or less) and 30-day mortality were similar in the 2 groups. At 12 months, New York Heart Association functional class had improved to class I or II in most patients in the PH (from 2.9% to 94.3%) and non-PH (from 9.4% to 96.9%) groups. The mean pulmonary artery systolic pressure of the PH group significantly decreased from baseline but remained higher than that of the non-PH group (50.8 ± 15.3 vs 36.7 ± 11.6 mm Hg, p <0.001). After a mean of 25.0 ± 16.9 months of follow-up, Kaplan-Meier analysis demonstrated significantly higher all-cause mortality in the PH group. In Cox regression analysis, preexisting PH was the most powerful predictor of all-cause mortality (hazard ratio 3.731, 95% confidence interval 1.653 to 8.475, p = 0.002). In conclusion, MitraClip therapy reduced FMR and alleviated symptoms with an excellent early safety profile in the PH and non-PH groups. However, preexisting PH was associated with worse all-cause mortality.

Optimizing procedural outcomes in percutaneous mitral valve therapy using transesophageal imaging: a stepwise analysis.

Moderate or severe mitral regurgitation is the most common valve disease in the USA. Without treatment, severe mitral regurgitation has a 5-year survival rate of approximately 40%. Surgery plays a pivotal role in the treatment of these patients. However, close to 50% of patients can be denied surgery due to being deemed to be high risk. The pioneering work of St Goar led to the development of a catheter-based system, the MitraClip™, that percutaneously accomplishes the Alfieri's method. With this percutaneous technique, rather than sutures, one or two clips are placed under transesophageal guidance attaching the midportions of the anterior and posterior leaflets, creating a double mitral orifice. The procedure requires seven basic steps with strong collaboration between the interventional cardiologist and echocardiologist. This paper focuses on the role of echocardiography for patient selection and procedural guidance for the MitraClip insertion.

Comparison between transradial and transfemoral percutaneous coronary intervention in acute ST-elevation myocardial infarction.

Transradial (TR) access is increasingly being used in percutaneous coronary intervention (PCI). However, its role in PCI for ST-segment elevation myocardial infarction remains controversial because of concerns of procedural complexity adversely affecting the promptness of reperfusion. In this study, 150 consecutive patients who underwent PCI for acute ST-segment elevation myocardial infarction over a period of 24 months were prospectively evaluated; 46 had TR access (31%) and 104 (69%) had transfemoral (TF) access. All patients received thienopyridines, aspirin, and heparin per routine management. There were no significant differences between the TR access and TF access groups with respect to age (62.2 ± 11.6 vs 64.7 ± 14.1, p = 0.28), gender (76.1% vs 72.1% men, p = 0.69), or incidence of diabetes (23.9% vs 26.9%, p = 0.84). The TR and TF access groups were comparable with respect to door-to-balloon time (79.2 ± 32.3 vs 86.8 ± 51.8 minutes, p = 0.67) and amount of contrast used (190.5 ± 101.5 vs 172.2 ± 81.7 ml, p = 0.24). Total fluoroscopy time was longer in the TR access group compared to the TF access group (21.7 ± 12.7 vs 14.4 ± 10.4 minutes, p <0.0001). Postprocedural Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow was comparable for the 2 groups (87% for the TF group and 96% for the TR group, p = 0.15). There were no vascular complications in the TR access group compared to the TF access group (0% vs 5.8%, p = 0.18). In conclusion, this single-center observational study shows that TR access for PCI in STEMI is feasible and that it has fewer vascular complications and shorter length of hospital stay than the TF approach.

MitraClip: a novel percutaneous approach to mitral valve repair.

As life expectancy increases, valvular heart disease is becoming more common. Management of heart disease and primarily valvular heart disease is expected to represent a significant proportion of healthcare provided to the elderly population. Recent years have brought a progression of surgical treatments toward less invasive strategies. This has given rise to percutaneous approaches for the correction of valvular heart disease. Percutaneous mitral valve repair using the MitraClip system (Abbott Vascular, Santa Clara, CA, USA) creates a double orifice and has been successfully used in selected patients with mitral regurgitation. We review the rationale, procedural aspects, and clinical data thus far available for the MitraClip approach to mitral regurgitation.

Contemporary application of cardiovascular hemodynamics: transcatheter mitral valve interventions.

Since the development and refinement of echocardiography, this technique has, for some time, been the mainstay for hemodynamic assessment of the mitral valve. This article discusses the key components of the invasive hemodynamic assessment of mitral valve disease and illustrates their utility through percutaneous transluminal mitral valvuloplasty for mitral stenosis and the novel transcatheter mitral valve repair using the MitraClip for mitral regurgitation. Changes in left atrial pressure and waveform, mean gradient, and cardiac output are critical assessment parameters for both safety and efficacy. Invasive hemodynamic assessment is an essential complement to echocardiography for the optimal guidance of these procedures.

Utility of combined two-dimensional and three-dimensional transesophageal imaging for catheter-based mitral valve clip repair of mitral regurgitation.

BACKGROUND: Catheter-based mitral valve clip repair (CBMCR) is feasible for selected patients with mitral regurgitation (MR). Two-dimensional (2D) transesophageal echocardiography (TEE) is the standard modality for evaluating MR and procedural guidance. Recently, real-time three-dimensional TEE became available. The aim of this study was to evaluate the value of combined 2D and three-dimensional TEE for CBMCR. In evaluating MR for CBMCR, the confidence of interpretation of 2D TEE was compared with that of combined imaging for the localization of major valve pathology. In patients who underwent CBMCR, the outcomes and the duration of CBMCR were compared. METHODS: In this retrospective study, MR evaluation was performed by 2D TEE alone and by combined imaging in 80 and 57 patients, respectively. CBMCR was guided by 2D TEE alone in 20 patients and by combined imaging in 39 patients. RESULTS: Examination by combined imaging allowed en face visualization of mitral valve anatomy and MR jet origin. The confidence of interpretation by combined imaging was higher than for 2D TEE (1.1 ± 0.3 vs 1.8 ± 0.7, P < .001).The guidance of CBMCR by combined imaging facilitated alignment of the catheter trajectory, clip positioning, and orientation of clip arms. The procedural success and final MR grade were not different between the two study groups. However, the procedural time of CBMCR using combined imaging compared with that using 2D TEE guidance alone was shorter (241 ± 58 vs 201 ± 68 min, P = .035). CONCLUSIONS: The use of combined imaging compared with 2D TEE alone appears to enhance the confidence of interpretation concerning mitral pathology and catheter-clip system location and may also reduce CBMCR time.

Percutaneous mitral valve repair: potential in heart failure management.

As a large portion of the US demographic advances into the later decades of life, the incidence of valvular heart disease is expected to increase. Mitral regurgitation (MR) caused by primary valve abnormality (degenerative) or secondary to cardiomyopathy (functional) is an important cause of heart failure. Management of valvular heart disease is expected to account for a large segment of services provided to heart failure patients. Recent years have seen a transition from surgical therapy to minimally invasive techniques, specifically percutaneous approaches for the correction of heart valve disease. The double orifice technique of mitral valve repair using the MitraClip System (Abbott Vascular, Menlo Park, CA) is one of many percutaneous approaches to treat significant MR. This technique is effective in patients with both degenerative and functional MR, reducing MR severity and improving heart failure symptoms. Broad acceptance of this percutaneous technology requires collaboration among cardiologists and cardiac surgeons in centers with superior catheter experience and knowledge of echocardiography.