Kar, Saibal

Background: Atrial fibrillation (AF), mitral regurgitation (MR), and left ventricular (LV) ejection fraction have a complex interplay. We evaluated the role of AF in patients with heart failure and moderate-to-severe or severe secondary MR enrolled in the randomized COAPT trial (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation) and its impact on mechanisms and outcomes with the MitraClip. Methods: Patients in the COAPT trial were stratified by the presence (n=327) or absence (n=287) of a history of AF and by assignment to treatment group. Clinical, echocardiographic, and outcome measures were assessed. The primary outcome was the composite rate of death or heart failure hospitalization at 24 months. Results: Patients with history of AF were older and more often male. They had a higher LV ejection fraction, larger left atrial volumes and mitral valve orifice areas, smaller LV volumes, and similar MR severity. Patients with AF compared with those without a history of AF had a higher unadjusted (hazard ratio [HR], 1.32 [95% CI, 1.06–1.64], P =0.01) and adjusted (HR, 1.30 [1.03–1.64], P =0.03) 2-year rate of the primary outcome. Treatment with the MitraClip compared with guideline-directed medical therapy alone reduced death or heart failure hospitalization in both those with (HR, 0.61 [0.46–0.82]) and without (HR, 0.46 [0.33–0.66]) a history of AF ( P int =0.18). Treatment with the MitraClip was associated with a lower risk of stroke in patients with a history of AF (HR, 0.18 [0.04–0.86]) but not in those without a history of AF (HR, 1.64 [0.58–4.62]; P int =0.02). Conclusions: In the COAPT trial, patients with a history of AF had larger left atrial and mitral valve orifice areas with higher LV ejection fraction and smaller LV volumes, suggesting an atrial mechanism contribution to functional MR. Despite the worse prognosis of heart failure patients with a history of AF, MR reduction with the MitraClip still afforded substantial clinical benefits. Treatment with MitraClip was associated with a lower risk of stroke in patients with a history of AF. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01626079.

Background: Transcatheter mitral valve replacement using aortic transcatheter heart valves has recently become an alternative for patients with degenerated mitral bioprostheses, failed surgical repairs with annuloplasty rings or severe mitral annular calcification who are poor surgical candidates. Outcomes of these procedures are collected in the Society of Thoracic Surgeons/American College of Cardiology/Transcatheter Valve Therapy Registry. A comprehensive analysis of mitral valve-in-valve (MViV), mitral valve-in-ring (MViR), and valve-in-mitral annular calcification (ViMAC) outcomes has not been performed. We sought to evaluate short-term outcomes of early experience with MViV, MViR, and ViMAC in the United States. Methods: Retrospective analysis of data from the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry. Results: Nine hundred three high-risk patients (median Society of Thoracic Surgeons score 10%) underwent MViV (n=680), MViR (n=123), or ViMAC (n=100) between March 2013 and June 2017 at 172 hospitals. Median age was 75 years, 59.2% female. Technical and procedural success were higher in MViV. Left ventricular outflow tract obstruction occurred more frequently with ViMAC (ViMAC=10%, MViR=4.9%, MViV=0.7%; P <0.001). In-hospital mortality (MViV=6.3%, MViR=9%, ViMAC=18%; P =0.004) and 30-day mortality (MViV=8.1%, MViR=11.5%, ViMAC=21.8%; P =0.003) were higher in ViMAC. At 30-day follow-up, median mean mitral valve gradient was 7 mm Hg, most patients (96.7%) had mitral regurgitation grade ≤1 (+) and were in New York Heart Association class I to II (81.7%). Conclusions: MViV using aortic balloon-expandable transcatheter heart valves is associated with a low complication rate, a 30-day mortality lower than predicted by the Society of Thoracic Surgeons score, and superior short-term outcomes than MViR and ViMAC. At 30 days, patients in all groups experienced improvement of symptoms, and valve performance remained stable. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02245763.

Background: In patients with atrial fibrillation, left atrial appendage closure with the Watchman device prevents thromboembolism from the left atrial appendage; however, thrombus may form on the left atrial face of the device, and then potentially embolize. Herein, we studied the incidence, predictors, and clinical outcome of device-related thrombus (DRT) using a large series of clinical trial cohorts of patients undergoing Watchman implantation. Methods: We studied the device arms of 4 prospective Food and Drug Administration trials: PROTECT-AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) (n=463); PREVAIL (Evaluation of the Watchman LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy) (n=269); CAP (Continued Access to PROTECT AF registry) (n=566); and CAP2 (Continued Access to PREVAIL registry) (n=578). Surveillance transesophageal echocardiographs were performed at 45 days and 12 months in all patients, and also at 6 months in the randomized control trials. We assessed both the incidence of DRT during these transesophageal echocardiographs (and other unscheduled transesophageal echocardiographs), and clinical outcomes of postprocedure stroke or systemic embolism (SSE) and adjusted for CHA 2 DS 2 -VASC and HAS-BLED scores. Results: Of 1739 patients who received an implant (7159 patient-years follow-up; CHA 2 DS 2 -VASc=4.0), DRT was seen in 65 patients (3.74%). The rates of SSE with and without DRT were 7.46 and 1.78 per 100 patient-years (adjusted rate ratio, 3.55; 95% confidence interval [CI], 2.18–5.79; P <0.001), and ischemic SSE rates were 6.28 and 1.65 per 100 patient-years (adjusted rate ratio, 3.22; 95% CI, 1.90–5.45, P <0.001). On multivariable modeling analysis, the predictors of DRT were as follows: history of transient ischemic attack or stroke (odds ratio [OR], 2.31; 95% CI, 1.26–4.25; P =0.007), permanent atrial fibrillation (OR, 2.24; 95% CI, 1.19–4.20; P =0.012); vascular disease (OR, 2.06; 95% CI, 1.08–3.91; P =0.028); left atrial appendage diameter (OR, 1.06 per mm increase; 95% CI, 1.01–1.12; P =0.019); left ventricular ejection fraction (OR, 0.96 per 1% increase; 95% CI, 0.94–0.99; P =0.009). DRT and SSE both occurred in 17 of 65 patients (26.2%). Of the 19 SSE events in these patients with DRT, 9 of 19 (47.4%) and 12 of 19 (63.2%) occurred within 1 and 6 months of DRT detection. Conversely, after left atrial appendage closure, most SSEs (123/142, 86.62%) occurred in patients without DRT. Conclusions: After left atrial appendage closure with Watchman, DRT (≈3.7%) is not frequent but, when present, is associated with a higher rate of stroke and systemic embolism.

Background— The Watchman Left Atrial Appendage System for Embolic Protection in Patients With AF (PROTECT AF) randomized trial compared left atrial appendage closure against warfarin in atrial fibrillation (AF) patients with CHADS 2 ≥1. Although the study met the primary efficacy end point of being noninferior to warfarin therapy for the prevention of stroke/systemic embolism/cardiovascular death, there was a significantly higher risk of complications, predominantly pericardial effusion and procedural stroke related to air embolism. Here, we report the influence of experience on the safety of percutaneous left atrial appendage closure. Methods and Results— The study cohort for this analysis included patients in the PROTECT AF trial who underwent attempted device left atrial appendage closure (n=542 patients) and those from a subsequent nonrandomized registry of patients undergoing Watchman implantation (Continued Access Protocol [CAP] Registry; n=460 patients). The safety end point included bleeding- and procedure-related events (pericardial effusion, stroke, device embolization). There was a significant decline in the rate of procedure- or device-related safety events within 7 days of the procedure across the 2 studies, with 7.7% and 3.7% of patients, respectively, experiencing events ( P =0.007), and between the first and second halves of PROTECT AF and CAP, with 10.0%, 5.5%, and 3.7% of patients, respectively, experiencing events ( P =0.006). The rate of serious pericardial effusion within 7 days of implantation, which had made up >50% of the safety events in PROTECT AF, was lower in the CAP Registry (5.0% versus 2.2%, respectively; P =0.019). There was a similar experience-related improvement in procedure-related stroke (0.9% versus 0%, respectively; P =0.039). Finally, the functional impact of these safety events, as defined by significant disability or death, was statistically superior in the Watchman group compared with the warfarin group in PROTECT AF. This remained true whether significance was defined as a change in the modified Rankin score of ≥1, ≥2, or ≥3 (1.8 versus 4.3 events per 100 patient-years; relative risk, 0.43; 95% confidence interval, 0.24 to 0.82; 1.5 versus 3.7 events per 100 patient-years; relative risk, 0.41; 95% confidence interval, 0.22 to 0.82; and 1.4 versus 3.3 events per 100 patient-years; relative risk, 0.43; 95% confidence interval, 0.22 to 0.88, respectively). Conclusion— As with all interventional procedures, there is a significant improvement in the safety of Watchman left atrial appendage closure with increased operator experience. Clinical Trial Registration— URL: http://clinicaltrials.gov . Unique identifier: NCT00129545.