Watchman Implantation Research Articles

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions of individuals worldwide. The rapid, irregular, and disordered electrical activity in the atria gives rise to palpitations, fatigue, dyspnea, chest pain and dizziness with or without syncope. Patients with AF have a five-fold higher risk of stroke. Oral anticoagulation (OAC) with warfarin is commonly used for stroke prevention in patients with AF and has been shown to reduce the risk of stroke by 64%. Warfarin therapy has several major disadvantages, however, including bleeding, non-tolerance, interactions with other medications and foods, non-compliance and a narrow therapeutic range. These issues, together with poor appreciation of the risk-benefit ratio, unawareness of guidelines, or absence of an OAC monitoring outpatient clinic may explain why only 30-60% of patients with AF are prescribed this drug. The problems associated with warfarin, combined with the limited efficacy and/or serious side effects associated with other medications used for AF, highlight the need for effective non-pharmacological approaches to treatment. One such approach is catheter ablation (CA), a procedure in which a radiofrequency electrical current is applied to regions of the heart to create small ablation lesions that electrically isolate potential AF triggers. CA is a well-established treatment for AF symptoms, that may also decrease the risk of stroke. Recent data showed a significant decrease in the relative risk of stroke and transient ischemic attack events among patients who underwent ablation compared with those undergoing antiarrhythmic drug therapy. Since the left atrial appendage (LAA) is the source of thrombi in more than 90% of patients with non-valvular atrial fibrillation, another approach to stroke prevention is to physically block clots from exiting the LAA. One method for occluding the LAA is via percutaneous placement of the WATCHMAN LAA closure device. The WATCHMAN device resembles a small parachute. It consists of a nitinol frame covered by fabric polyethyl terephthalate that prevents emboli, but not blood, from exiting during the healing process. Fixation anchors around the perimeter secure the device in the LAA (Figure 1). To date, the WATCHMAN is the only implanted percutaneous device for which a randomized clinical trial has been reported. In this study, implantation of the WATCHMAN was found to be at least as effective as warfarin in preventing stroke (all-causes) and death (all-causes). This device received the Conformité Européenne (CE) mark for use in the European Union for warfarin eligible patients and in those who have a contraindication to anticoagulation therapy. Given the proven effectiveness of CA to alleviate AF symptoms and the promising data with regard to reduction of thromboembolic events with both CA and WATCHMAN implantation, combining the two procedures is hoped to further reduce the incidence of stroke in high-risk patients while simultaneously relieving symptoms. The combined procedure may eventually enable patients to undergo implantation of the WATCHMAN device without subsequent warfarin treatment, since the CA procedure itself reduces thromboembolic events. This would present an avenue of treatment previously unavailable to patients ineligible for warfarin treatment because of recurrent bleeding or other warfarin-associated problems. The combined procedure is performed under general anesthesia with biplane fluoroscopy and TEE guidance. Catheter ablation is followed by implantation of the WATCHMAN LAA closure device. Data from a non-randomized trial with 10 patients demonstrates that this procedure can be safely performed in patients with a CHADS2 score of greater than 1. Further studies to examine the effectiveness of the combined procedure in reducing symptoms from AF and associated stroke are therefore warranted.

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions of individuals worldwide 1-3. The rapid, irregular, and disordered electrical activity in the atria gives rise to palpitations, fatigue, dyspnea, chest pain and dizziness with or without syncope 4, 5. Patients with AF have a five-fold higher risk of stroke 6. Oral anticoagulation (OAC) with warfarin is commonly used for stroke prevention in patients with AF and has been shown to reduce the risk of stroke by 64% 7. Warfarin therapy has several major disadvantages, however, including bleeding, non-tolerance, interactions with other medications and foods, non-compliance and a narrow therapeutic range 8-11. These issues, together with poor appreciation of the risk-benefit ratio, unawareness of guidelines, or absence of an OAC monitoring outpatient clinic may explain why only 30-60% of patients with AF are prescribed this drug 8. The problems associated with warfarin, combined with the limited efficacy and/or serious side effects associated with other medications used for AF 12,13, highlight the need for effective non-pharmacological approaches to treatment. One such approach is catheter ablation (CA), a procedure in which a radiofrequency electrical current is applied to regions of the heart to create small ablation lesions that electrically isolate potential AF triggers 4. CA is a well-established treatment for AF symptoms 14, 15, that may also decrease the risk of stroke. Recent data showed a significant decrease in the relative risk of stroke and transient ischemic attack events among patients who underwent ablation compared with those undergoing antiarrhythmic drug therapy 16. Since the left atrial appendage (LAA) is the source of thrombi in more than 90% of patients with non-valvular atrial fibrillation 17, another approach to stroke prevention is to physically block clots from exiting the LAA. One method for occluding the LAA is via percutaneous placement of the WATCHMAN LAA closure device. The WATCHMAN device resembles a small parachute. It consists of a nitinol frame covered by fabric polyethyl terephthalate that prevents emboli, but not blood, from exiting during the healing process. Fixation anchors around the perimeter secure the device in the LAA (Figure 1). To date, the WATCHMAN is the only implanted percutaneous device for which a randomized clinical trial has been reported. In this study, implantation of the WATCHMAN was found to be at least as effective as warfarin in preventing stroke (all-causes) and death (all-causes) 18. This device received the Conformité Européenne (CE) mark for use in the European Union for warfarin eligible patients and in those who have a contraindication to anticoagulation therapy 19. Given the proven effectiveness of CA to alleviate AF symptoms and the promising data with regard to reduction of thromboembolic events with both CA and WATCHMAN implantation, combining the two procedures is hoped to further reduce the incidence of stroke in high-risk patients while simultaneously relieving symptoms. The combined procedure may eventually enable patients to undergo implantation of the WATCHMAN device without subsequent warfarin treatment, since the CA procedure itself reduces thromboembolic events. This would present an avenue of treatment previously unavailable to patients ineligible for warfarin treatment because of recurrent bleeding 20 or other warfarin-associated problems. The combined procedure is performed under general anesthesia with biplane fluoroscopy and TEE guidance. Catheter ablation is followed by implantation of the WATCHMAN LAA closure device. Data from a non-randomized trial with 10 patients demonstrates that this procedure can be safely performed in patients with a CHADS2 score of greater than 1 21. Further studies to examine the effectiveness of the combined procedure in reducing symptoms from AF and associated stroke are therefore warranted.

Circulation: Clinical Summaries

<i>Circulation:</i> Clinical Summaries

Atrial Fibrillation Through the Years

Information about a real patient is presented in stages (boldface type) to an expert clinician (Dr Valentin Fuster), who responds to the information, sharing his reasoning with the reader (regular type). A discussion by the authors follows. A 61-year-old man presents with 2 weeks of exertional dyspnea. Pertinent medical history includes hypertension, nephrolithiasis, and internal hemorrhoids. He takes no medications and has no known drug allergies. His father died after a myocardial infarction at 57 years of age. He formerly smoked 1 pack of cigarettes daily for 15 years but ceased tobacco use 10 years before presentation. He ingests 2 glasses of alcohol weekly and denies illicit drug use. His caffeine intake is limited. He is an architect and is married, with healthy children. On physical examination, his temperature is 98.0°F, blood pressure is 130/85 mm Hg bilaterally, pulse is irregular at 130 beats per minute, and respiratory rate is 18 breaths per minute with an oxygen saturation of 97% while breathing room air. He is a slender white man in no distress. His jugular venous pressure is elevated at 14 cm H 2 O. There is no thyromegaly, and the carotid upstrokes are brisk, without bruits. Cardiovascular examination reveals a rapid and irregular heart rhythm with variation in the intensity of the first heart sound. The point of maximal impulse is not displaced. The remainder of the chest and abdominal examination is within normal limits. The extremities are warm and show mild pitting edema. Laboratory testing is significant for normal renal function and electrolytes, but a hemogram reveals a mild thrombocytopenia of 90 000 platelets/μL. ECG demonstrates atrial fibrillation (AF) with an average ventricular rate of 123 bpm ( Figure 1 ). Figure 1. The 12-lead ECG showing atrial fibrillation with a rapid ventricular rate. Dr Valentin Fuster : This is a …

Abstract 19638: Watchman Left Atrial Appendage Closure in Atrial Fibrillation Patients with Contraindication to Oral Anticoagulation: The ‰ASA Plavix Registry” (ASAP)

Background: AF patients at the highest risk for embolic stroke also experience the greatest risk of hemorrhagic complications of anticoagulant use. The PROTECT AF trial revealed that LAA closure using the Watchman device was non-inferior to Warfarin for preventing stroke in AF pts with CHADS 2 ≥ 1. However, these pts were treated with Warfarin post-implant until a TEE demonstrated LAA closure at 6 wks. Due to the pressing need for strategies that can prevent stroke in pts with contraindications to Warfarin, we performed a prospective study of Watchman implantation in Warfarin-contraindicated pts. Methods: Prospective registry of pts with non-valvular AF, a CHADS 2 score ≥1, and a contraindication to Warfarin use. The Watchman device was implanted in standard fashion. Post-implant, patients were discharged on 6 mo of clopidogrel and life-long aspirin. Follow-up TEE was performed at 3/12 months. Results: At 4 centers, 150 pts were enrolled. The mean age was 72.5 ± 7.4 yrs. The prevalence of stroke risk factors was: CHF in 29%, HTN in 95%, Age ≥ 75 in 43%, DM in 32%, and stroke/TIA in 41%. The mean CHADS 2 score was 2.8 ± 1.2. The reason for Warfarin contraindication was: hemorrhagic tendencies (26%), blood dyscrasias (7%), bleeding tendencies (67%), unsupervised pts with senility/high fall risk (4%), and other (5%). Watchman implantation was successful in 95% (142/150). At 14.2 ± 8.7 mo of follow-up, there were 4 strokes (3 ischemic) and 6 instances of device-related thrombus by TEE. The observed rate of ischemic stroke 1.7% represents 77% fewer events from that expected in pts with a similar CHADS2 score treated with aspirin alone (7.3%; Figure). Data from additional follow-up (to a total of &gt;250 pt-yrs) will be available. Conclusion: Watchman implantation without a Warfarin transition is safe and effective in AF pts with contraindications to even short-term oral anticoagulation

TCT-83 Watchman Left Atrial Appendage Closure in Atrial Fibrillation Patients with Contraindication to Oral Anticoagulation: the “Aspirin Plavix Registry” (ASAP)

Background: AF patients at the highest risk for embolic stroke also experience the greatest risk of hemorrhagic complications of anticoagulant use. The PROTECT AF trial revealed that LAA closure using the Watchman device was non-inferior to Warfarin for preventing stroke in AF pts with CHADS2 ≥ 1. However, these pts were treated with Warfarin post-implant until a TEE demonstrated LAA closure at 6 wks. Due to the pressing need for strategies that can prevent stroke in pts with contraindications to Warfarin, we performed a prospective study of Watchman implantation in Warfarin-contraindicated pts. Methods: Prospective registry of pts with non-valvular AF, a CHADS2 score ≥1, and a contraindication to Warfarin use. The Watchman device was implanted in standard fashion. Post-implant, patients were discharged on 6 mo of clopidogrel and life-long aspirin. Follow-up TEE was performed at 3/12 months. Results: At 4 centers, 150 pts were enrolled. The mean age was 72.5 ± 7.4 yrs. The prevalence of stroke risk factor...

Watchman Implantation without Warfarin Transition is Feasible in Patients with Atrial Fibrillation

Watchman Implantation without Warfarin Transition is Feasible in Patients with Atrial Fibrillation

First Formal Analysis of the “ASA Plavix Registry” (ASAP): Watchman Left Atrial Appendage Closure in Atrial Fibrillation Patients With Contradication to Oral Anticoagulation

Introduction: Patients with atrial fibrillation (AF) at the highest risk for embolic stroke also experience the greatest risk of hemorrhagic complications of anticoagulant use. The PROTECT AF trial revealed that left atrial appendage closure using the Watchman device was noninferior to warfarin for preventing stroke in patients with AF with a CHADS2 score of ≥ 1. However, these patients were treated with warfarin postimplant until a TEE demonstrated left atrial appendage closure at 6 weeks. Because of the pressing need for strategies that can prevent stroke in patients with contraindications to warfarin, we performed a prospective study of Watchman implantation in warfarin-contraindicated patients.

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 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 &gt;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.

The Incidence and Long-Term Clinical Outcome of Iatrogenic Atrial Septal Defects Secondary to Transseptal Catheterization With a 12F Transseptal Sheath

Studies assessing the presence of a residual iatrogenic atrial septal defect (iASD) after transseptal catheterization with 8F transseptal sheaths have suggested that the majority of these iASDs close within 6 months. However, these studies have been limited by small patient numbers and short follow-up. Additionally, there are a number of novel catheter procedures in interventional cardiology and electrophysiology that use larger transseptal sheaths. The objective of this study was to assess the incidence of and complications associated with iASDs in a large cohort of patients undergoing transseptal catheterization with a 12F transseptal sheath. Patients (n=253) without a preexisting interatrial shunt undergoing WATCHMAN implantation as part of the PROTECT AF study were included in this current study. Patients underwent transesophageal echocardiography with echo-contrast immediately after the procedure and at 45 days and 6 months and 12 months. Eighty-seven percent of patients had an iASD immediately after the procedure, the majority of which sealed by 6 months (incidence of iASD, 34% at 45 days, 11% at 6 months, 7% at 12 months). Whereas the majority of iASDs were >3 mm in diameter immediately after the procedure, the minority of iASD were >3 mm during the follow-up period. Additionally, interatrial shunting was predominantly left-to-right when an iASD was present. There was no significant difference in the rate of stroke and/or systemic embolism during the follow-up period in patients with or without iASD. Transseptal catheterization procedures with a large-diameter transseptal sheath have a high spontaneous closure rate of iASDs that is not associated with an increased rate of stroke/systemic embolization during long-term follow-up.