Changes in Left Atrial Appendage Dimensions Following Volume Loading During Percutaneous Left Atrial Appendage Closure

ObjectivesThis study sought to determine whether volume loading alters the left atrial appendage (LAA) dimensions in patients undergoing percutaneous LAA closure.BackgroundPercutaneous LAA closure is increasingly performed in patients with atrial fibrillation and contraindications to anticoagulation, to lower their stroke and systemic embolism risk. The safety and efficacy of LAA closure relies on accurate device sizing, which necessitates accurate measurement of LAA dimensions. LAA size may change with volume status, and because patients are fasting for these procedures, intraprocedural measurements may not be representative of true LAA size.MethodsThirty-one consecutive patients undergoing percutaneous LAA closure who received volume loading during the procedure were included in this study. After an overnight fast and induction of general anesthesia, patients had their LAA dimensions (orifice and depth) measured by transesophageal echocardiography before and after 500 to 1,000 ml of intravenous normal saline, aiming for a left atrial pressure >12 mm Hg.ResultsSuccessful implantation of LAA closure device was achieved in all patients. The average orifice size of the LAA at baseline was 20.5 mm at 90°, and 22.5 mm at 135°. Following volume loading, the average orifice size of the LAA increased to 22.5 mm at 90°, and 23.5 mm at 135°. The average increase in orifice was 1.9 mm (p < 0.0001). The depth of the LAA also increased by an average of 2.5 mm after volume loading (p < 0.0001).ConclusionsIntraprocedural volume loading with saline increased the LAA orifice and depth dimensions during LAA closure. Operators should consider optimizing the left atrial pressure with volume loading before final device sizing.     

Percutaneous Left Atrial Appendage Closure With the Watchman Device: Long-Term Results Up to 5 Years

ObjectivesThe aim of this study was to evaluate long-term outcomes in patients with atrial fibrillation undergoing percutaneous left atrial appendage (LAA) closure with the Watchman device.BackgroundAtrial fibrillation is one of the most common arrhythmias and is associated with a high risk for cardioembolic ischemic events, most notably stroke. Percutaneous LAA closure is an alternative to oral anticoagulation, because most thrombi originate from the LAA.MethodsAll consecutive patients with minimum CHADS₂ or CHA₂DS₂-VASc scores of 1 who underwent LAA closure with the Watchman device between June 2006 and August 2010 were eligible. Follow-up examinations were performed after 45 days to 3 months, 6 months, and 1 year and thereafter annually. Afterward, alternating office visits and telephone follow-up were performed every 6 months.ResultsA total of 102 patients were included. The mean age was 71.6 ± 8.8 years, and 37.3% were women. The mean CHADS₂ and CHA₂DS₂-VASc scores were 2.7 ± 1.3 and 4.3 ± 1.7, respectively. Procedural success was achieved in 96.1% of patients. During a mean follow-up period of 3.0 ± 1.6 years, the annual rates of transient ischemic attack, stroke, intracranial hemorrhage, and death were 0.7%, 0.7%, 1.1%, and 3.5%, respectively.ConclusionsLAA closure with the Watchman device is safe and feasible for stroke protection in patients with atrial fibrillation. Low ischemic events rates demonstrate its effectiveness during long-term follow-up.     

Periprocedural Intracardiac Echocardiography for Left Atrial Appendage Closure: A Dual-Center Experience

ObjectivesThis dual-center study sought to demonstrate the utility and safety of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to transesophageal echocardiography (TEE) during Amplatzer Cardiac Plug device implantation.BackgroundOver 90% of intracardiac thrombi in atrial fibrillation originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA percutaneous occlusion. TEE is typically used to guide implantation.MethodsICE-guided percutaneous LAA closure was performed in 121 patients to evaluate the following tasks typically achieved by TEE: assessment of the LAA dimension for device sizing; guidance of transseptal puncture; verification of the delivery sheath position; confirmation of location and stability of the device before and after release and continuous monitoring to detect procedural complications. In 51 consecutive patients, we compared the measurements obtained by ICE and fluoroscopy to choose the size of the device.ResultsThe device was successfully implanted in 117 patients, yielding a technical success rate of 96.7%. Procedural success was achieved in 113 cases (93.4%). Four major adverse events (3 cardiac tamponades and 1 in-hospital transient ischemic attack) occurred. There was significant correlation in the measurements for device sizing assessed by angiography and ICE (r = 0.94, p < 0.0001).ConclusionsICE imaging was able to perform the tasks typically provided by TEE during implantation of the Amplatzer Cardiac Plug device for LAA occlusion. Therefore, we provide evidence that the use of ICE offered accurate measurements of LAA dimension in order to select the correct device sizes.     

Bleeding Outcomes After Left Atrial Appendage Closure Compared With Long-Term Warfarin: A Pooled,Patient-Level Analysis of the WATCHMAN Randomized Trial Experience

ObjectivesThe purpose of this study was to compare the relative risk of major bleeding with left atrial appendage (LAA) closure compared with long-term warfarin therapy.BackgroundLAA closure is an alternative approach to chronic oral anticoagulation for the prevention of thromboembolism in patients with atrial fibrillation (AF).MethodsWe conducted a pooled, patient-level analysis of the 2 randomized clinical trials that compared WATCHMAN (Boston Scientific, Natick, Massachusetts) LAA closure with long-term warfarin therapy in AF.ResultsA total of 1,114 patients were included, with a median follow-up of 3.1 years. The overall rate of major bleeding from randomization to the end of follow-up was similar between treatment groups (3.5 events vs. 3.6 events per 100 patient-years; rate ratio [RR]: 0.96; 95% confidence interval [CI]: 0.66 to 1.40; p = 0.84). LAA closure significantly reduced bleeding >7 days post-randomization (1.8 events vs. 3.6 events per 100 patient-years; RR: 0.49; 95% CI: 0.32 to 0.75; p = 0.001), with the difference emerging 6 months after randomization (1.0 events vs. 3.5 events per 100 patient-years; RR: 0.28; 95% CI: 0.16 to 0.49; p < 0.001), when patients assigned to LAA closure were able to discontinue adjunctive oral anticoagulation and antiplatelet therapy. The reduction in bleeding with LAA closure was directionally consistent across all patient subgroups.ConclusionsThere was no difference in the overall rate of major bleeding in patients assigned to LAA closure compared with extended warfarin therapy over 3 years of follow-up. However, LAA closure significantly reduced bleeding beyond the procedural period, particularly once adjunctive pharmacotherapy was discontinued. The favorable effect of LAA closure on long-term bleeding should be considered when selecting a stroke prevention strategy for patients with nonvalvular AF. (WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation; NCT00129545; and Evaluation of the WATCHMAN LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy [PREVAIL]; NCT01182441)     

Percutaneous Left Atrial Appendage Closure: Procedural Techniques and Outcomes

Percutaneous left atrial appendage closure technology for stroke prevention in patients with atrial fibrillation has significantly advanced in the past 2 decades. Several devices are under clinical investigation, and a few have already received Conformité Européene (CE)-mark approval and are available in many countries. The WATCHMAN device (Boston Scientific, Natick, Massachusetts) has the most supportive data and is under evaluation by the U.S. Food and Drug Administration for warfarin-eligible patients. The Amplatzer Cardiac Plug (St. Jude Medical, Plymouth, Minnesota) has a large real-world experience over the past 5 years, and a randomized trial comparing Amplatzer Cardiac Plug with the WATCHMAN device is anticipated in the near future. The Lariat procedure (SentreHEART Inc., Redwood City, California) has also gained interest lately, but early studies were concerning for high rates of serious pericardial effusion and major bleeding. The current real-world experience predominantly involves patients who are not long-term anticoagulation candidates or who are perceived to have high bleeding risks. This pattern of practice is expected to change when the U.S. Food and Drug Administration approves the WATCHMAN device for warfarin-eligible patients. This paper reviews in depth the procedural techniques, safety, and outcomes of the current leading devices.     

Noninvasive Imaging of Cardiovascular Injury Related to the Treatment of Cancer

The introduction of multiple treatments for cancer, including chemotherapeutic agents and radiation therapy, has significantly reduced cancer-related morbidity and mortality. However, these therapies can promote a variety of toxicities, among the most severe being the ones involving the cardiovascular system. Currently, for many surviving cancer patients, cardiovascular (CV) events represent the primary cause of morbidity and mortality. Recent data suggest that CV injury occurs early during cancer treatment, creating a substrate for subsequent cardiovascular events. Researchers have investigated the utility of noninvasive imaging strategies to detect the presence of CV injury during and after completion of cancer treatment because it starts early during cancer therapy, often preceding the development of chemotherapy or cancer therapeutics related cardiac dysfunction. In this State-of-the-Art Paper, we review the utility of current clinical and investigative CV noninvasive modalities for the identification and characterization of cancer treatment-related CV toxicity.     

Persistence of Iatrogenic Atrial Septal Defect After Interventional Mitral Valve Repair With the MitraClip System: A Note of Caution

ObjectivesThe purpose of this study was to investigate the persistence rates of iatrogenic atrial septal defect (iASD) after interventional edge-to-edge repair with serial transesophageal echocardiography examinations and close clinical follow-up (FU).BackgroundTranscatheter mitral valve repair (TMVR) with the MitraClip system (Abbott Vascular, Abbott Park, Illinois) is a therapeutic alternative to surgery in selected high-risk patients. Clip placement requires interatrial transseptal puncture and meticulous manipulation of the steerable sheath. The persistence of iASD after MitraClip procedures and its clinical relevance is unknown.MethodsA total of 66 patients (76.7% male, mean age 77.1 ± 7.9 years) with symptomatic mitral regurgitation (MR) at prohibitive surgical risk (EuroSCORE II 10.1 ± 6.1%) underwent MitraClip procedures and completed 6 months of FU.ResultsTransesophageal echocardiography after FU showed persistent iASD in 50% of cases. Patients with iASD did not significantly differ from patients without ASD concerning baseline characteristics, New York Heart Association functional class, severity of MR, and acute procedural success rates (p > 0.05). When comparing procedural details and hemodynamic measures between groups, MitraClip procedures took longer in patients without iASD (82.4 ± 39.7 min vs. 68.9 ± 45.5 min; p = 0.05), and echocardiography after FU showed less decrease of systolic pulmonary artery pressures in the iASD group (−1.6 ± 14.1 mm Hg vs. 9.3 ± 17.4 mm Hg; p = 0.02). Clinically, patients with iASD presented more often with New York Heart Association functional classes >II after FU (57% vs. 30%; p = 0.04), showed higher levels of N-terminal pro-brain natriuretic peptide (6,667.3 ± 7,363.9 ng/dl vs. 4,835.9 ± 6,681.7 ng/dl; p = 0.05), and had less improvement in 6-min walking distances (20.8 ± 107.4 m vs. 114.6 ± 116.4 m; p = 0.001). Patients with iASD showed higher death rates during 6 months (16.6% vs. 3.3%; p = 0.05). Cox regression analysis found that only persistence of iASD (p = 0.04) was associated with 6-month survival.ConclusionsThe persistence rate of 50% iASD after MitraClip procedures is considerably high. Persistent interatrial shunting was associated with worse clinical outcomes and increased mortality. Further studies are warranted to investigate if persistent interatrial shunting is the mediator or marker of advanced disease in these patients.     

Efficacy of Polymer Injection for Ischemic Mitral Regurgitation: Persistent Reduction of Mitral Regurgitation and Attenuation of Left Ventricular Remodeling

ObjectivesThe aim of this study was to examine the chronic effects of polyvinyl-alcohol (PVA) injection on mitral regurgitation (MR) reduction, mitral valve geometry, and left ventricular (LV) remodeling in a chronic ischemic MR sheep model.BackgroundPrevious studies have demonstrated acute efficacy of PVA hydrogel polymer injection into infarcted myocardium underlying the papillary muscle to relieve MR by papillary muscle repositioning. However, the chronic efficacy of PVA injection in the chronic infarction setting remains unclear.MethodsSixteen sheep developed chronic MR 8 weeks after induced inferoposterior myocardial infarction. Ten consecutive sheep underwent PVA injection (PVA group) and 6 sheep served as control subjects with saline injection. Epicardial 2-/3-dimensional echocardiography was performed at the baseline, chronic MR (pre-injection), and sacrifice (8 weeks after injection) stages.ResultsBoth groups were comparable at the baseline and chronic MR stages. At sacrifice, MR decreased from moderate to trace or mild (vena contracta: 0.17 ± 0.08 cm vs. 0.56 ± 0.10 cm, p < 0.001) in the PVA group but progressed to moderate to severe in the control group. End-systolic and -diastolic volumes remained stable in the PVA group but increased significantly in the control group (both p < 0.05). At sacrifice, compared with the control group, the PVA group had significantly less left ventricular remodeling (end-systolic volume: 41.1 ± 10.4 ml vs. 55.9 ± 12.4 ml, p < 0.05), lower MR severity (vena contracta: 0.17 ± 0.08 cm vs. 0.60 ± 0.14 cm, p < 0.01), and favorable changes in mitral valve geometry.ConclusionsPolymer injection in a chronic ischemic MR model results in persistent reduction of MR and attenuation of continued left ventricular remodeling over 8 weeks of follow-up.     

Childhood Obesity: Impact on Cardiac Geometry and Function

ObjectivesThe aim of our study was to assess geometric and functional changes of the heart in obese compared with nonobese children and adolescents.BackgroundObesity in children and adolescents has increased over the past decades and is considered a strong risk factor for future cardiovascular morbidity and mortality. Obesity has been associated with myocardial structural alterations that may influence cardiac mechanics.MethodsWe prospectively recruited 61 obese (13.5 ± 2.7 years of age, 46% male sex, SD score body mass index, 2.52 ± 0.60) and 40 nonobese (14.1 ± 2.8 years of age, 50% male sex, SD score body mass index, −0.33 ± 0.83) consecutive, nonselected Caucasian children and adolescents. A standardized 2-dimensional (2D) echocardiography and 2D speckle-tracking analysis was performed in all children. Furthermore, blood chemistry including lipid and glucose metabolism was assessed in all children.ResultsCompared with nonobese children, blood pressure, low-density lipoprotein cholesterol, and parameters of glucose metabolism were significantly increased in obese children, whereas high-density lipoprotein cholesterol was significantly lower. Compared with nonobese children, obese children were characterized by enlarged left- and right-sided cardiac chambers, thicker left ventricular walls, and, consequently, increased left ventricular mass. Despite a comparable left ventricular ejection fraction, decreased tissue Doppler–derived peak systolic velocity and regional basoseptal strain were found in obese children compared with nonobese children. Beyond that, 2D speckle tracking–derived longitudinal (−18.2 ± 2.0 vs. −20.5 ± 2.3, p < 0.001) and circumferential (−17.0 ± 2.7 vs. −19.5 ± 2.9, p < 0.001) strain of the left ventricle was reduced in obese children compared with nonobese children. Diastolic function was also impaired in obese compared with nonobese children. Both longitudinal strain and circumferential strain were independently associated with obesity.ConclusionsThe results of this study demonstrate that childhood obesity is associated with significant changes in myocardial geometry and function, indicating an early onset of potentially unfavorable alterations in the myocardium.     

Left atrial appendage dysfunction in acute embolic stroke young patients with sinus rhythm: Correlation with Tissue Doppler mitral annular systolic velocity

BackgroundTrans-esophageal echocardiogram (TEE) is a gold standard test for diagnosis of left atrial (LA) appendage function.AimTo evaluate left atrial appendage (LAA) dysfunction using mitral annular systolic velocity measured by tissue Doppler imaging “Sm” in acute embolic stroke young patients with sinus rhythm.MethodsTransthoracic (TTE) and transesophageal echocardiography (TEE) were performed in 70 consecutive patients with sinus rhythm without obvious left ventricular dysfunction within 2 weeks after embolic stroke. Two groups were identified: LAA dysfunction [LAA emptying peak flow velocity (LAA-eV) <0.55 m/s, n = 28, age 52 ± 11 years] and without LAA dysfunction (LAA-eV ≥ 0.55 m/s, n = 42, age 54 ± 10 years) on TEE. Tissue Doppler mitral annular systolic velocity “Sm” was obtained in apical four chambers view on TTE and D-dimer level estimated for all patients.ResultsSm was significantly lower in patients with than in those without LAA dysfunction (P < 0.0001). There was a significant correlation between Sm, LAVI, LAEF%, E/A ratio and LAA-eV in all selected patients groups. The optimum cut-off value of Sm for predicting LAA dysfunction was below or equal 8 cm/s (sensitivity 89.6% and specificity 94.2%).ConclusionTissue Doppler mitral annular systolic velocity is an independent non-invasive easy predictor of LAA dysfunction and significantly correlated with LAA-eV (p < 0.0001) in acute embolic stroke young patients with sinus rhythm.