Saibal Kar

Percutaneous Mitral Repair With the MitraClip System : Safety and Midterm Durability in the Initial EVEREST (Endovascular Valve Edge-to-Edge REpair Study) Cohort

OBJECTIVES We undertook a prospective multicenter single-arm study to evaluate the feasibility, safety, and efficacy of the MitraClip system (Evalve Inc., Menlo Park, California). BACKGROUND Mitral valve repair for mitral regurgitation (MR) has been performed by the use of a surgically created double orifice. Percutaneous repair based on this surgical approach has been developed by use of the Evalve MitraClip device to secure the mitral leaflets. METHODS Patients with 3 to 4+ MR were selected in accordance with the American Heart Association/American College of Cardiology guidelines for intervention and a core echocardiographic laboratory. RESULTS A total of 107 patients were treated. Ten (9%) had a major adverse event, including 1 nonprocedural death. Freedom from clip embolization was 100%. Partial clip detachment occurred in 10 (9%) patients. Overall, 79 of 107 (74%) patients achieved acute procedural success, and 51 (64%) were discharged with MR of < or =1+. Thirty-two patients (30%) had mitral valve surgery during the 3.2 years after clip procedures. When repair was planned, 84% (21 of 25) were successful. Thus, surgical options were preserved. A total of 50 of 76 (66%) successfully treated patients were free from death, mitral valve surgery, or MR >2+ at 12 months (primary efficacy end point). Kaplan-Meier freedom from death was 95.9%, 94.0%, and 90.1%, and Kaplan-Meier freedom from surgery was 88.5%, 83.2%, and 76.3% at 1, 2, and 3 years, respectively. The 23 patients with functional MR had similar acute results and durability. CONCLUSIONS Percutaneous repair with the MitraClip system can be accomplished with low rates of morbidity and mortality and with acute MR reduction to < 2+ in the majority of patients, and with sustained freedom from death, surgery, or recurrent MR in a substantial proportion (EVEREST I; NCT00209339. EVEREST II; NCT00209274).

Closure or Medical Therapy for Cryptogenic Stroke with Patent Foramen Ovale

BACKGROUND The prevalence of patent foramen ovale among patients with cryptogenic stroke is higher than that in the general population. Closure with a percutaneous device is often recommended in such patients, but it is not known whether this intervention reduces the risk of recurrent stroke. METHODS We conducted a multicenter, randomized, open-label trial of closure with a percutaneous device, as compared with medical therapy alone, in patients between 18 and 60 years of age who presented with a cryptogenic stroke or transient ischemic attack (TIA) and had a patent foramen ovale. The primary end point was a composite of stroke or transient ischemic attack during 2 years of follow-up, death from any cause during the first 30 days, or death from neurologic causes between 31 days and 2 years. RESULTS A total of 909 patients were enrolled in the trial. The cumulative incidence (Kaplan-Meier estimate) of the primary end point was 5.5% in the closure group (447 patients) as compared with 6.8% in the medical-therapy group (462 patients) (adjusted hazard ratio, 0.78; 95% confidence interval, 0.45 to 1.35; P=0.37). The respective rates were 2.9% and 3.1% for stroke (P=0.79) and 3.1% and 4.1% for TIA (P=0.44). No deaths occurred by 30 days in either group, and there were no deaths from neurologic causes during the 2-year follow-up period. A cause other than paradoxical embolism was usually apparent in patients with recurrent neurologic events. CONCLUSIONS In patients with cryptogenic stroke or TIA who had a patent foramen ovale, closure with a device did not offer a greater benefit than medical therapy alone for the prevention of recurrent stroke or TIA. (Funded by NMT Medical; ClinicalTrials.gov number, NCT00201461.).

Safety of Percutaneous Left Atrial Appendage Closure Results From the Watchman Left Atrial Appendage System for Embolic Protection in Patients With AF (PROTECT AF) Clinical Trial and the Continued Access Registry

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 CHADS2 ≥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.

Safety of Percutaneous Left Atrial Appendage Closure

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 CHADS2 ≥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.

Acute and 12-Month Results With Catheter-Based Mitral Valve Leaflet Repair : The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study

OBJECTIVES The EVEREST II (Endovascular Valve Edge-to-Edge Repair) High Risk Study (HRS) assessed the safety and effectiveness of the MitraClip device (Abbott Vascular, Santa Clara, California) in patients with significant mitral regurgitation (MR) at high risk of surgical mortality rate. BACKGROUND Patients with severe MR (3 to 4+) at high risk of surgery may benefit from percutaneous mitral leaflet repair, a potentially safer approach to reduce MR. METHODS Patients with severe symptomatic MR and an estimated surgical mortality rate of ≥12% were enrolled. A comparator group of patients screened concurrently but not enrolled were identified retrospectively and consented to compare survival in patients treated by standard care. RESULTS Seventy-eight patients underwent the MitraClip procedure. Their mean age was 77 years, >50% had previous cardiac surgery, and 46 had functional MR and 32 degenerative MR. MitraClip devices were successfully placed in 96% of patients. Protocol-predicted surgical mortality rate in the HRS and concurrent comparator group was 18.2% and 17.4%, respectively, and Society of Thoracic Surgeons calculator estimated mortality rate was 14.2% and 14.9%, respectively. The 30-day procedure-related mortality rate was 7.7% in the HRS and 8.3% in the comparator group (p = NS). The 12-month survival rate was 76% in the HRS and 55% in the concurrent comparator group (p = 0.047). In surviving patients with matched baseline and 12-month data, 78% had an MR grade of ≤2+. Left ventricular end-diastolic volume improved from 172 ml to 140 ml and end-systolic volume improved from 82 ml to 73 ml (both p = 0.001). New York Heart Association functional class improved from III/IV at baseline in 89% to class I/II in 74% (p < 0.0001). Quality of life was improved (Short Form-36 physical component score increased from 32.1 to 36.1 [p = 0.014] and the mental component score from 45.5 to 48.7 [p = 0.065]) at 12 months. The annual rate of hospitalization for congestive heart failure in surviving patients with matched data decreased from 0.59 to 0.32 (p = 0.034). CONCLUSIONS The MitraClip device reduced MR in a majority of patients deemed at high risk of surgery, resulting in improvement in clinical symptoms and significant left ventricular reverse remodeling over 12 months. (Pivotal Study of a Percutaneous Mitral Valve Repair System [EVEREST II]; NCT00209274).

Percutaneous Left Atrial Appendage Closure vs Warfarin for Atrial Fibrillation A Randomized Clinical Trial

IMPORTANCE While effective in preventing stroke in patients with atrial fibrillation (AF), warfarin is limited by a narrow therapeutic profile, a need for lifelong coagulation monitoring, and multiple drug and diet interactions. OBJECTIVE To determine whether a local strategy of mechanical left atrial appendage (LAA) closure was noninferior to warfarin. DESIGN, SETTING, AND PARTICIPANTS PROTECT AF was a multicenter, randomized (2:1), unblinded, Bayesian-designed study conducted at 59 hospitals of 707 patients with nonvalvular AF and at least 1 additional stroke risk factor (CHADS2 score ≥1). Enrollment occurred between February 2005 and June 2008 and included 4-year follow-up through October 2012. Noninferiority required a posterior probability greater than 97.5% and superiority a probability of 95% or greater; the noninferiority margin was a rate ratio of 2.0 comparing event rates between treatment groups. INTERVENTIONS Left atrial appendage closure with the device (n = 463) or warfarin (n = 244; target international normalized ratio, 2-3). MAIN OUTCOMES AND MEASURES A composite efficacy end point including stroke, systemic embolism, and cardiovascular/unexplained death, analyzed by intention-to-treat. RESULTS At a mean (SD) follow-up of 3.8 (1.7) years (2621 patient-years), there were 39 events among 463 patients (8.4%) in the device group for a primary event rate of 2.3 events per 100 patient-years, compared with 34 events among 244 patients (13.9%) for a primary event rate of 3.8 events per 100 patient-years with warfarin (rate ratio, 0.60; 95% credible interval, 0.41-1.05), meeting prespecified criteria for both noninferiority (posterior probability, >99.9%) and superiority (posterior probability, 96.0%). Patients in the device group demonstrated lower rates of both cardiovascular mortality (1.0 events per 100 patient-years for the device group [17/463 patients, 3.7%] vs 2.4 events per 100 patient-years with warfarin [22/244 patients, 9.0%]; hazard ratio [HR], 0.40; 95% CI, 0.21-0.75; P = .005) and all-cause mortality (3.2 events per 100 patient-years for the device group [57/466 patients, 12.3%] vs 4.8 events per 100 patient-years with warfarin [44/244 patients, 18.0%]; HR, 0.66; 95% CI, 0.45-0.98; P = .04). CONCLUSIONS AND RELEVANCE After 3.8 years of follow-up among patients with nonvalvular AF at elevated risk for stroke, percutaneous LAA closure met criteria for both noninferiority and superiority, compared with warfarin, for preventing the combined outcome of stroke, systemic embolism, and cardiovascular death, as well as superiority for cardiovascular and all-cause mortality. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00129545.

Mechanisms of Cardiac Nerve Sprouting After Myocardial Infarction in Dogs

Cardiac nerve sprouting and sympathetic hyperinnervation after myocardial infarction (MI) both contribute to arrhythmogenesis and sudden death. However, the mechanisms responsible for nerve sprouting after MI are unclear. The expression of nerve growth factor (NGF), growth associated protein 43 (GAP43), and other nerve markers were studied at the infarcted site, the noninfarcted left ventricle free wall (LVFW), and the left stellate ganglion (LSG) at several time points (30 minutes to 1 month) after MI. Transcardiac (difference between coronary sinus and aorta) NGF levels were also assayed. Acute MI resulted in the immediate elevation of the transcardiac NGF concentration within 3.5 hours after MI, followed by the upregulation of cardiac NGF and GAP43 expression, which was earlier and more pronounced at the infarcted site than the noninfarcted LVFW. However, cardiac nerve sprouting and sympathetic hyperinnervation were more pronounced in the noninfarcted than the infarcted LVFW site and peaked at 1 week after MI. The NGF and GAP43 protein levels significantly increased in the LSG from 3 days (P <0.01 for all) after MI, without a concomitant increase in mRNA. There was persistent elevation of NGF levels in aorta and coronary sinus within 1 month after MI. We conclude MI results in immediate local NGF release, followed by upregulation of NGF and GAP43 expression at the infarcted site. NGF and GAP43 are transported retrogradely to LSG, which triggers nerve sprouting at the noninfarcted LVFW. A rapid and persistent upregulation of NGF and GAP43 expression at the infarcted site underlies the mechanisms of cardiac nerve sprouting after MI.

Physician-Directed Patient Self-Management of Left Atrial Pressure in Advanced Chronic Heart Failure

Background— Previous studies suggest that management of ambulatory hemodynamics may improve outcomes in chronic heart failure. We conducted a prospective, observational, first-in-human study of a physician-directed patient self-management system targeting left atrial pressure. Methods and Results— Forty patients with reduced or preserved left ventricular ejection fraction and a history of New York Heart Association class III or IV heart failure and acute decompensation were implanted with an investigational left atrial pressure monitor, and readings were acquired twice daily. For the first 3 months, patients and clinicians were blinded as to these readings, and treatment continued per usual clinical assessment. Thereafter, left atrial pressure and individualized therapy instructions guided by these pressures were disclosed to the patient. Event-free survival was determined over a median follow-up of 25 months (range 3 to 38 months). Survival without decompensation was 61% at 3 years, and events tended to be less frequent after the first 3 months (hazard ratio 0.16 [95% confidence interval 0.04 to 0.68], P=0.012). Mean daily left atrial pressure fell from 17.6 mm Hg (95% confidence interval 15.8 to 19.4 mm Hg) in the first 3 months to 14.8 mm Hg (95% confidence interval 13.0 to 16.6 mm Hg; P=0.003) during pressure-guided therapy. The frequency of elevated readings (>25 mm Hg) was reduced by 67% (P<0.001). There were improvements in New York Heart Association class (−0.7±0.8, P<0.001) and left ventricular ejection fraction (7±10%, P<0.001). Doses of angiotensin-converting enzyme/angiotensin-receptor blockers and &bgr;-blockers were uptitrated by 37% (P<0.001) and 40% (P<0.001), respectively, whereas doses of loop diuretics fell by 27% (P=0.15). Conclusions— Physician-directed patient self-management of left atrial pressure has the potential to improve hemodynamics, symptoms, and outcomes in advanced heart failure. Clinical Trial Registration Information— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00547729.

Six- and Twelve-Month Results From First Human Experience Using Everolimus-Eluting Stents With Bioabsorbable Polymer

Background—Everolimus, an active immunosuppressive and antiproliferative agent of the same family as sirolimus (rapamycin), has demonstrated significant reduction of neointimal proliferation in animal studies. The First Use To Underscore restenosis Reduction with Everolimus (FUTURE) I trial was the first in-human experience to evaluate the safety and efficacy of everolimus-eluting stents (EES), coated with a bioabsorbable polymer, compared with bare metal stents (BMS). Methods and Results—FUTURE I was a prospective, single-blind, randomized trial that enrolled 42 patients with de novo coronary lesions (EES 27, BMS 15). Patient and lesion characteristics were comparable between the groups. Major adverse cardiac event rates were low at 30 days and 6 months, without any early or late stent thrombosis for either group (P =NS). Between 6 and 12 months, there were no additional reports of major adverse cardiac events. The 6-month angiographic in-stent restenosis rate was 0% versus 9.1% (1 patient) (P =NS), with an associated late loss of 0.11 mm versus 0.85 mm (P <0.001), and the in-segment restenosis rate was 4% (1 patient) and 9.1% (1 patient) (P =NS) for EES and BMS, respectively. Intravascular ultrasound analysis revealed a significant reduction of percent neointimal volume in EES compared with BMS (2.9±1.9 mm3 /mm versus 22.4±9.4 mm3 /mm, P <0.001). There was no late stent malapposition in either group. The safety and efficacy of the EES appeared to be sustained at 12 months. Conclusions—In this initial clinical experience, EES with bioabsorbable polymer demonstrated a safe and efficacious method to reduce in-stent neointimal hyperplasia and restenosis.

Percutaneous Mitral Valve Repair for Mitral Regurgitation in High-Risk Patients: Results of the EVEREST II Study

BACKGROUND The EVEREST II (Endovascular Valve Edge-to-Edge REpair STudy) High-Risk registry and REALISM Continued Access Study High-Risk Arm are prospective registries of patients who received the MitraClip device (Abbott Vascular, Santa Clara, California) for mitral regurgitation (MR) in the United States. OBJECTIVES The purpose of this study was to report 12-month outcomes in high-risk patients treated with the percutaneous mitral valve edge-to-edge repair. METHODS Patients with grades 3 to 4+ MR and a surgical mortality risk of ≥12%, based on the Society of Thoracic Surgeons risk calculator or the estimate of a surgeon coinvestigator following pre-specified protocol criteria, were enrolled. RESULTS In the studies, 327 of 351 patients completed 12 months of follow-up. Patients were elderly (76 ± 11 years of age), with 70% having functional MR and 60% having prior cardiac surgery. The mitral valve device reduced MR to ≤2+ in 86% of patients at discharge (n = 325; p < 0.0001). Major adverse events at 30 days included death in 4.8%, myocardial infarction in 1.1%, and stroke in 2.6%. At 12 months, MR was ≤2+ in 84% of patients (n = 225; p < 0.0001). From baseline to 12 months, left ventricular (LV) end-diastolic volume improved from 161 ± 56 ml to 143 ± 53 ml (n = 203; p < 0.0001) and LV end-systolic volume improved from 87 ± 47 ml to 79 ± 44 ml (n = 202; p < 0.0001). New York Heart Association functional class improved from 82% in class III/IV at baseline to 83% in class I/II at 12 months (n = 234; p < 0.0001). The 36-item Short Form Health Survey physical and mental quality-of-life scores improved from baseline to 12 months (n = 191; p < 0.0001). Annual hospitalization rate for heart failure fell from 0.79% pre-procedure to 0.41% post-procedure (n = 338; p < 0.0001). Kaplan-Meier survival estimate at 12 months was 77.2%. CONCLUSIONS The percutaneous mitral valve device significantly reduced MR, improved clinical symptoms, and decreased LV dimensions at 12 months in this high-surgical-risk cohort. (Endovascular Valve Edge-to-Edge REpair STudy [EVERESTIIRCT]; NCT00209274).