Interventional and surgical occlusion of the left atrial appendage

Understanding the role of the left atrial appendage on the flow in the atrium

BACKGROUND

The exclusion/occlusion of the left atrial appendage (LAA) is a treatment option for atrial fibrillation (AF) patients who are at high risk of stroke and high risk of bleeding. As the role of the LAA is not well understood or explored, this study aims to assess its role on flow dynamics in the left atrium.

METHODS

Computational fluid dynamics (CFD) simulations were carried out for nine AF patients before and after LAA exclusion. The flow parameters investigated included the LA velocities, Time Averaged Wall Shear Stress (TAWSS), Oscillatory Shear Index (OSI), Relative Residence Time (RRT), and Pressure in the LA.

RESULTS

This study shows that, on average, a decrease in TAWSS (1.82 ± 1.85 Pa to 1.27 ± 0.96 Pa, p < 0.05) and a slight increase in OSI (0.16 ± 0.10 to 0.17 ± 0.10, p < 0.05), RRT (1.87 ± 1.84 Pa-1 to 2.11 ± 1.78 Pa-1, p < 0.05), and pressure (-19.2 ± 6.8 mmHg to -15.3 ± 8.3 mmHg, p < 0.05) were observed in the LA after the exclusion of the LAA, with a decrease in low-magnitude velocities.

CONCLUSION

The exclusion of the LAA seems to be associated with changes in LA flow dynamics. Further studies are needed to elucidate the clinical implications of these changes.

Optimizing antithrombotic therapy in patients with coexisting cardiovascular and gastrointestinal disease

Balancing the safety and efficacy of antithrombotic agents in patients with gastrointestinal disorders is challenging because of the potential for interference with the absorption of antithrombotic drugs and for an increased risk of bleeding. In this Review, we address considerations for enteral antithrombotic therapy in patients with cardiovascular disease and gastrointestinal comorbidities. For those with gastrointestinal bleeding (GIB), we summarize a general scheme for risk stratification and clinical evidence on risk reduction approaches, such as limiting the use of concomitant medications that increase the risk of GIB and the potential utility of gastrointestinal protection strategies (such as proton pump inhibitors or histamine type 2 receptor antagonists). Furthermore, we summarize the best available evidence and potential gaps in our knowledge on tailoring antithrombotic therapy in patients with active or recent GIB and in those at high risk of GIB but without active or recent GIB. Finally, we review the recommendations provided by major medical societies, highlighting the crucial role of teamwork and multidisciplinary discussions to customize the antithrombotic regimen in patients with coexisting cardiovascular and gastrointestinal diseases.

The role of CT in arrhythmia management-treatment planning and post-procedural imaging surveillance

Several interventional treatment options exist in patients with atrial and ventricular arrhythmia. Cardiac CT is routinely performed prior to occlusion of the left atrial appendage, pulmonary vein isolation, and cardiac device implantation. Besides the evaluation of coronary artery disease, cardiac CT provides isotropic, high-resolution CT images of the cardiac anatomy with the possibility of multiplanar reformations and three-dimensional reconstructions which are helpful to guide interventional treatment. In addition, cardiac CT is increasingly used to rapidly evaluate periprocedural complications and for the routine post-procedural imaging surveillance in patients after interventions. This review article will discuss current applications of pre- and post-interventional CT imaging in patients with arrhythmia.

Novel technique of left atrial appendage occlusion-a pilot study

A clot in the left atrial appendage (LAA) is an important cause of cardio-embolic stroke. Concomitant occlusion of the LAA during cardiac surgery is found to have reduced postoperative stroke. A study was designed to observe the results of LAA occlusion in 17 patients undergoing coronary artery bypass graft surgery (CABG) and aortic valve replacement (AVR). The LAA was occluded epicardially with a SIRONIX 60-mm linear noncutting stapler (Healthium Medtech Pvt limited, Peenya, Bengaluru). The effectiveness of occlusion was confirmed by trans-esophageal echocardiography and at 2 years of follow-up with trans-thoracic echocardiography. There was no re-canalization of the LAA, and the patients remained in sinus rhythm. Concomitant LAA occlusion with a linear stapler during cardiac surgery is a safe, feasible, and reproducible option.

Left Atrial Appendage Occlusion: Current Stroke Prevention Strategies and a Shift Toward Data-Driven, Patient-Specific Approaches

The left atrial appendage (LAA) is a complex structure with unknown physiologic function protruding from the main body of the left atrium. In patients with atrial fibrillation, the left atrium does not contract effectively. Insufficient atrial and LAA contractility predisposes the LAA morphology to hemostasis and thrombus formation, leading to an increased risk of cardioembolic events. Oral anticoagulation therapies are the mainstay of stroke prevention options for patients; however, not all patients are candidates for long-term oral anticoagulation. Percutaneous occlusion devices are an attractive alternative to long-term anticoagulation therapy, although they are not without limitations, such as peri-implant leakage and device-related thrombosis. Although efforts have been made to reduce these risks, significant interpatient heterogeneity inevitably yields some degree of device-anatomy mismatch that is difficult to resolve using current devices and can ultimately lead to insufficient occlusion and poor patient outcomes. In this state-of-the-art review, we evaluated the anatomy of the LAA as well as the current pathophysiologic understanding and stroke prevention strategies used in the management of the risk of stroke associated with atrial fibrillation. We highlighted recent advances in computed tomography imaging, preprocedural planning, computational modeling, and novel additive manufacturing techniques, which represent the tools needed for a paradigm shift toward patient-centric LAA occlusion. Together, we envisage that these techniques will facilitate a pipeline from the imaging of patient anatomy to patient-specific computational and bench-top models that enable customized, data-driven approaches for LAA occlusion that are engineered specifically to meet each patient's unique needs.

Left atrial appendage occlusion in a mirror-image dextrocardia: A case report and review of literature

BACKGROUND

In mirror-image dextrocardia, the anterior-posterior position of the cardiac chambers and great vessels is maintained, but the left-right orientation of the abdominal organs is reversed. The abnormal anatomy of the heart poses surgical challenges and problems in dealing with surgical risk and monitoring complications. There are few reports on closure of the left atrial appendage (LAA) in dextrocardia and no reports on the application of enhanced recovery after surgery (ERAS) following LAA occlusion (LAAO) procedures.

CASE SUMMARY

The objective for this case was to ensure perioperative safety and accelerate postoperative recovery from LAAO in a patient with mirror-image dextrocardia. ERAS was guided by the theory and practice of nursing care. Atrial fibrillation was diagnosed in a 77-year-old male patient, in whom LAAO was performed. The 2019 guidelines for perioperative care after cardiac surgery recommend that the clinical nursing procedures for patients with LAAO should be optimized to reduce the incidence of perioperative complications and ensure patient safety. Music therapy can be used throughout perioperative treatment and nursing to improve the anxiety symptoms of patients.

CONCLUSION

The procedure was uneventful and proceeded without complications. Anxiety symptoms were improved.

Surface modification to enhance cell migration on biomaterials and its combination with 3D structural design of occluders to improve interventional treatment of heart diseases

The dominant source of thromboembolism in heart comes from the left atrial appendage (LAA). An occluder can close LAA and significantly reduce the risk of strokes, particularly for those patients with atrial fibrillation. However, it is technically challenging to fabricate an LAA occluder that is appropriate for percutaneous implantation and can be rapidly endothelialized to accomplish complete closure and avoid severe complication. Hypothesizing that a fast migration rate of endothelial cells on the implant surface would lead to rapid endothelialization, we fabricated an LAA occlusion device for interventional treatment with a well-designed 3D architecture and a nanoscale 2D coating. Through screening of biomaterials surfaces with cellular studies in vitro including cell observations, qPCR, RNA sequencing, and implantation studies in vivo, we revealed that a titanium-nitrogen nanocoating on a NiTi alloy promoted high migration rate of endothelial cells on the surface. The effectiveness of this first nanocoating LAA occluder was validated in animal experiments and a patient case, both of which exhibited successful implantation, fast sealing and long-term safety of the device. The mechanistic insights gained in this study will be useful for the design of medical devices with appropriate surface modification, not necessarily for improved cell adhesion but sometimes for enhanced cell migration.

Recent developments in next-generation occlusion devices

Transcatheter closure has been widely accepted as a highly effective way to treat abnormal blood flows and/or embolization of thrombus in the heart. It allows the closure of four types of congenital heart defects (CHDs) and stroke-associated left atrial appendage (LAA). The four types of CHDs include atrial septal defect (ASD), patent foramen ovale (PFO), patent ductus arteriosus (PDA), and ventricular septal defect (VSD). Advancements in the materials and configurations of occlusion devices have spurred the transition from open-heart surgery with high complexity and morbidity, or lifelong medication with a high risk of bleeding, to minimally invasive deployment. A variety of occlusion devices have been developed over the past few decades, particularly novel ones represented by biodegradable and 3D-printed occlusion devices, which are considered as next-generation alternatives to conventional Nitinol-based occlusion devices due to biodegradability, customization, and improved biocompatibility. The aim here is to comprehensively review the next-generation occlusion devices in terms of materials, configurations, manufacturing methods, deployment strategies, and (if available) experimental results or clinical data. The current challenges and the direction of future work are also proposed. STATEMENT OF SIGNIFICANCE: Implantation of occlusion devices has become a widely accepted and highly effective treatment for occluding abnormal blood/thrombus flow within the heart. Due to the serious complications such as erosion and displacement of conventional Nitinol-based occluders, next-generation occluders with reduced risk of complications and improved biocompatibility has emerged. Here, we comprehensively review the next-generation occluders developed for atrial septal defect (ASD), patent foramen ovale (PFO), patent ductus arteriosus (PDA), ventricular septal defect (VSD), and left atrial appendage (LAA), with special emphasis on biodegradable occluders. Besides, intelligent materials (e.g., automatically deployable shape memory polymers) and rapid customized manufacturing methods (3D/4D printing) for the fabrication of occluders are also introduced. Lastly, the directions of future work are highlighted.

Plugs for left atrial appendage occlusion: an overview of available devices

INTRODUCTION

Approximately one-third of all ischemic strokes and the ensuing health and economic burden can be attributed to the presence of atrial fibrillation (AF). The global prevalence of AF continues to rise, thus making it by far the most common diagnosed cardiac arrhythmia. Percutaneous left atrial appendage (LAA) occlusion or obliteration has been developed to protect from the occurrence of stroke in patients with nonvalvular AF.

AREAS COVERED

We address the characteristics and techniques for implantation as well as some clinical registries and randomized trials of the various catheter-based devices for the occlusion of the LAA that are either currently available or in the clinical evaluation stage.

EXPERT OPINION

Over less than 2 decades, LAA occlusion progressed from being a concept applied in a few specialized centers to a globally recognized procedure implemented in numerous hospitals as part of daily interventional practice. The respective devices are to date safer and easier to deploy than initially. Periprocedural and postprocedural complications will continue to decrease as already evident from prospective randomized trials and registries. Although current indications focus on patients with nonvalvular AF and contraindications for oral anticoagulation, it is all but certain that the future will bring a widening in the spectrum of indications, applicability, and usage of these devices.

The relationship between incomplete surgical obliteration of the left atrial appendage and thromboembolic events after mitral valve surgery (from the ISOLATE Registry)

Left atrial appendage (LAA) is a common site of thrombus formation especially in patients with atrial fibrillation (AF). Complete surgical LAA closure (cSLC) is the surgical aim, however incomplete surgical LAA closure (iSLC) is not rare. In this study, we aimed to evaluate the risk of thromboembolic complications (TEC) in AF patients with iSLC after mitral valve surgery. A total of 101 AF patients (mean age: 61.8 ± 11.8 years; male:32), who underwent surgical suture ligation during mitral valve surgery were enrolled in this retrospective study. All patients underwent transthoracic and transesophageal echocardiography (TEE) at least 3 months after surgery. The primary outcome was the occurrence of TEC including any ischemic stroke, transient ischemic attack, coronary or peripheral embolism. TEE examination revealed cSLC in 66 (65.3%) and iSLC in 35 patients (34.6%). A total of 12 TECs (11.9%) occurred during a mean follow-up time of 41.1 ± 15.6 months. TECs were found to be significantly higher in the iSLC group (25.7% vs 4.5%, p = 0.002). The prevalence of iSLC was significantly higher in patients with TEC (75 vs. 29.2%, p = 0.002). High CHA₂DS₂-VASc Score and iSLC were found to be independent predictors of TEC. Long term TEC free survival was found to be significantly decreased in patients with iSLC. The presence of iSLC was associated with a significantly increased risk of TEC in AF patients after mitral valve surgery. Routine intraoperative and postoperative screening for iSLC by TEE and long-term strict anticoagulation therapy are recommended in these patients.

Impact of left atrial appendage closure on circulating microvesicles levels: The MICROPLUG study

BACKGROUND

Left atrial appendage occlusion (LAAO) has emerged as a valid alternative to oral anticoagulation therapy for the prevention of systemic embolism in patients with non-valvular atrial fibrillation (NVAF). Microvesicles (MVs) are shed-membrane particles generated during various cellular types activation/apoptosis that carry out diverse biological effects. LAA has been suspected to be a potential source of MVs during AF, but the effects its occlusion on circulating MVs levels are unknown.

METHODS

N = 25 LAAO and n = 25 control patients who underwent coronary angiography were included. Blood samples were drawn before and 48 h after procedure for all. A third sample was collected 6 weeks after procedure in LAAO patients. In N = 10 extra patients, samples were collected from right atrium, LAA and pulmonary vein during LAAO procedure. Circulating AnnV + procoagulant, endothelial, platelets, red blood cells/RBC and leukocytes derived-MVs were measured using flow cytometry methods.

RESULTS

In the LAAO group, AnnV+, platelets, RBC, and leukocytes MVs were significantly increased following intervention, whereas only AnnV + MVs levels significantly rose in controls. The 6-w analysis showed that RBC-MVs and AnnV + MVs levels were still significantly elevated compared to baseline values in LAAO patients. The in-site analysis revealed that leukocytes and CD62e + endothelial-MVs were significantly higher in left atrial appendage compared to pulmonary vein, suggesting a local increased production. No major adverse event was observed in any patient post procedural course.

CONCLUSIONS

LAAO impacts circulating MVs and might create mild pro-coagulant status and potential erythrocytes activation due to the device healing during the first weeks following intervention.

Epicardial left atrial appendage occlusion with a new medical device: assessment of procedural feasibility, safety and efficacy in a large animal model

Background

Left atrial appendage occlusion (LAAO) represents a treatment alternative to anticoagulation in patients with atrial fibrillation. We evaluate a novel device for epicardial LAAO in a translational canine model.

Methods

Nine hounds (n = 9) were used to assess usability, safety, and efficacy of the TigerPaw Pro (TPP) device for epicardial LAAO. Following baseline imaging (intra-cardiac echocardiography (ICE) and angiography) and intraoperative visual inspection, usability was tested via a ``closure/re-opening`` maneuver followed by deployment of a total of twenty TPP devices (n = 20) on the left and right atrial appendages respectively. Procedural safety was evaluated by assessing for adverse-events via direct Epicardial inspection and endocardial imaging. Efficacy evaluation included assessment of device positioning, presence of residual stumps and completeness of closure. Post-mortem evaluation was performed to confirm safety and efficacy.

Results

Usability testing of all TPP devices was successful (n = 20;100%, delivery-time range 22–120 s) without any procedural adverse-events (tissue damage or tears, bleeding, vessel-impingement, structural impact). All devices fully traversed the ostium (n = 18) or appendage body (n = 2), and conformed smoothly to adjacent cardiac anatomy. In nineteen deployments (n = 19;95%), all device connector pairs were fully engaged, while in one TPP device the most distal pair remained unengaged. ICE and post-mortem inspections revealed complete closure of all appendage ostia (n = 18;100%) and only in one case a small residual stump was detected. Intraoperative safety findings were further confirmed post-mortem. Devices created a nearly smooth line of closure via symmetric endocardial tissue-coaptation.

Conclusions

In this preclinical model, the TPP demonstrated good ease of use for ostial access, ability to re-position (after engagement) and rapid deployment, while achieving safe and effective LAAO.

Incidence and characteristics of left atrial appendage stumps after device-enabled epicardial closure

OBJECTIVES

High success rates for left atrial appendage (LAA) exclusion with the AtriClip (Atricure, USA) device have been reported in the literature. This study evaluated the presence and characteristics of residual LAA stumps after AtriClip LAA exclusion using postoperative short- and long-term computed tomography angiography (CTA).

METHODS

In this retrospective analysis, 43 of 291 consecutive patients undergoing cardiac surgery with concomitant LAA occlusion using the AtriClip device were identified with available postoperative short- and long-term follow-up by CTA. LAA patency and the absence or the size of a present residual LAA stump were assessed on 2-dimensional multiplanar reconstructions, on maximum intensity projection images and on volume-rendered 3-dimensional computed tomography reconstructions. Based on current recommendations, the threshold for a significant LAA stump length was defined <10 mm.

RESULTS

The LAA was successfully occluded in all 43 patients (100%) as confirmed by intraoperative transoesophageal echocardiography and CTA imaging with a mean follow-up duration of 7.1 ± 0.8 years post-implant. The absence of blood flow in the excluded LAA was confirmed in all cases. In 31 of 43 patients (72%), no residual stump (0 mm) was observed creating a smooth endocardial surface, CTA revealed residual LAA stumps in 11/43 patients (26%) with a length <10 mm and a significant residual stump with a depth of >10 mm (12 mm) in 1 patient (2%). The mean length, width and depth of the residual stumps were 5.8 ± 2.1, 4.4 ± 1.2 and 7.3 ± 2.3 mm, respectively.

CONCLUSIONS

This study investigated the incidence of residual stump formation (>10 mm) after LAA closure with the AtriClip device based on CTA imaging data obtained during short- and long-term follow-up. While no LAA stump was detectable in the majority of patients, a non-significant LAA stump (<10 mm) was present in 26% of cases, indicating a favourable LAA occlusion profile for the AtriClip device. However, although a LAA stump length <10 mm is currently considered clinically safe, this definition needs further attention in future studies with regards to its potential clinical implications.

[Left atrial appendage occlusion in patients with nonvalvular atrial fibrillation : Present evidence, ongoing studies, open questions]

About every fifth ischemic stroke is caused by atrial fibrillation. Oral anticoagulation is highly effective in secondary stroke prevention, but a relevant portion of patients with atrial fibrillation is not (permanently) anticoagulated for a variety of reasons. Based on present evidence, no general recommendation can be given for left atrial appendage occlusion in patients with nonvalvular atrial fibrillation. However, left atrial appendage occlusion is a treatment option after severe anticoagulation-related bleeding, if the cause of bleeding is not treatable. Left atrial appendage occlusion is critical in patients with a relative contraindication for oral anticoagulation or lack of adherence to given medication. It seems to be important that further randomized studies confirm a benefit of left atrial appendage occlusion in selected patients with nonvalvular atrial fibrillation. In addition, it is vital to clarify whether discontinuation of antiplatelets is feasible after catheter-based left atrial appendage occlusion, as antiplatelets are associated with a risk of bleeding. Within this review article, we discuss present evidence, gaps of knowledge and provide an overview on ongoing clinical studies. In addition, we summarize the design of the CLOSURE-AF study. This randomized multicenter study will start recruitment soon and is funded by the German Center for Cardiovascular Research e. V.

[Left atrial appendage closure in non-valvular atrial fibrillation]

Atrial fibrillation is the most frequent cardiac arrhythmia worldwide, causing approximately 20% of all ischemic strokes. Therefore, oral anticoagulation is recommended in patients with atrial fibrillation with at least a moderate risk of stroke; however, there is a significant proportion of patients who cannot undergo long-term oral anticoagulation. As the left atrial appendage is of major relevance for atrial fibrillation-induced thrombus formation, catheter-based or surgical closure of the left atrial appendage appears to be a promising therapeutic option. Large registry studies including patients with catheter-based left atrial appendage closure have proven its effectiveness and a decreasing procedure-related complication rate. This review article summarizes the current knowledge and introduces major ongoing randomized studies, which will investigate the impact of left atrial appendage closure on stroke prevention. The authors hope that the results of the randomized CLOSURE AF trial, which is funded by the German Center for Cardiovascular Research e. V. and is now recruiting patients in Germany, will help to solve many of the currently prevalent clinical questions.

Residual flow may increase the risk of adverse events in patients received combined catheter ablation and transcatheter left atrial appendage closure for nonvalvular atrial fibrillation: a meta-analysis

Background

Catheter ablation (CA) and left atrial appendage closure (LAAC) have been combined into a novel one-stop procedure for patients with atrial fibrillation (AF). However, postoperative complications are relatively common in patients undergoing LAAC; the complications, including residual flow, increase in the risk of bleeding, or other adverse events, are unknown in patients receiving one-stop therapy. Therefore, we tried to evaluate the adverse events of CA and LAAC hybrid therapy in patients with nonvalvular AF.

Methods

We performed a meta-analysis and computer-based literature search to identify publications listed in the PubMed, Embase, and Cochrane library databases. Studies were included if patients received CA and LAAC hybrid therapy and reported adverse events.

Results

Overall 13 studies involving 952 patients were eligible based on the inclusion criteria. In the periprocedural period, the pooled incidence of pericardial effusion was 3.15%. The rates of bleeding events and residual flow were 5.02 and 9.11%, respectively. During follow-up, the rates of all-cause mortality, embolism events, bleeding events, AF recurrence, and residual flow were 2.15, 5.24, 6.95, 32.89, and 15.35%, respectively. The maximum occurrence probability of residual flow events was 21.87%. Bleeding events were more common in patients with a higher procedural residual flow event rate (P = 0.03). A higher AF recurrence rate indicated higher rates of embolism events (P = 0.04) and residual flow (P = 0.03) during follow-up.

Conclusions

Bleeding events were more common in patients with a higher procedural residual flow event rate. However, combined CA and LAAC therapy is reasonably safe and efficacious in patients with nonvalvular AF. Further studies on the safety and efficacy of CA or LAAC alone are necessary in future.

"AF HeartTeam" Guided Indication for Stand-alone Thoracoscopic Left Atrial Ablation and Left Atrial Appendage Closure

Background

Traditional surgical treatment for patients with atrial fibrillation (AF) is performed via sternotomy and on cardiopulmonary bypass. It is very effective in regard to rhythm control, but remains unpopular due to its invasiveness. Truly endoscopic AF treatments have decreased the threshold for electrophysiologists (and cardiologists) to refer, and the reluctance of patients to accept a standalone surgical approach. Practice guidelines from around the world have recognized this as an acceptable therapeutic approach. Current guidelines recommend the HeartTeam approach in treating these complex AF cases. In this study we report our experience with AF HeartTeam approach for surgical stand-alone AF ablation.

Methods

The AF HeartTeam Program began in 2013, patients qualified for inclusion if either of the following was present: failed catheter ablation and/or medication, not suitable for catheter ablation, contraindication to anticoagulation, or patients preferring such an approach. All patients with a complex AF history were assessed by the AF HeartTeam, from which 42 patients were deemed suitable for a totally endoscopic AF procedure (epicardial ablation and LAA closure). Endpoints were intraoperative bidirectional block of the pulmonary veins and closure of left atrial appendage confirmed by transesophageal echocardiography (TEE). Post discharge rhythm follow-up was performed after 3 and 12, 24 and 36 months. Anticoagulation was discontinued 6 weeks after the procedure in patients after documented LAA closure.

Results

In total 42 patients underwent the endoscopic procedure (Median CHA2DS2-VASC=3 (1-6), HAS-BLED=2 (1-6)) for paroxysmal (15/42) and non-paroxysmal AF (27/42) respectively. Bidirectional block was obtained in all patients and complete LAA closure was obtained in all but one Patient on TEE (41/42). In one patient the LAA was not addressed due to extensive adhesions. Two patients underwent median sternotomy because of bleeding during the endoscopic surgery early in the series. There were no deaths. Procedure duration was a median of 124min (Range 83-211) and duration of hospitalization was median of 5 days (Range 3-12). During 36 months follow-up survival free of mortality, thromboembolic events or strokes was 100%. Twelve month freedom from atrial arrhythmia off anti-arrhythmic medication was 93% and 89% for paroxysmal and non-paroxysmal patients respectively. 6/42 patients who had an AF recurrence during the follow-up underwent touch-up catheter ablation.

Conclusions

Atrial fibrillation heart team approach provides excellent outcomes for patients with AF. This approach is beneficial for patients after failed catheter ablation or not candidates for such and offers a very effective mid-term outcome data. In addition to effective rhythm control the protective effect of epicardial LAA closure may play an important role in effectively reducing stroke. The creation of an AF HeartTeam as recommended by the guidelines insures unbiased therapies and provides access to this minimally invasive but effective therapeutic option for AF patients.

Multimodality Imaging for Best Dealing With Patients in Atrial Arrhythmias

The management of atrial fibrillation (AF) is not only a clinical challenge but also an imaging challenge. The role of different imaging modalities to estimate the thromboembolic risk in AF is a key clinical question. The present review summarizes the advances of myocardial imaging in the stratification of thromboembolic risk, diagnosis, and management of left atrial thrombosis in patients with AF. These imaging techniques are also important for understanding arrhythmias and their consequences. It is becoming fundamental for guiding therapy. Still, large studies are required, but be sure that left atrial imaging will become more and more clinically fundamental.

The growing clinical spectrum of cerebral amyloid angiopathy

PURPOSE OF REVIEW

Cerebral amyloid angiopathy (CAA) is diagnosed primarily as a cause of lobar intracerebral hemorrhages (ICH) in elderly patients. With improving MRI techniques, however, the role of CAA in causing other symptoms has become clear. Recognizing the full clinical spectrum of CAA is important for diagnosis and treatment. In this review we summarize recent insights in clinical CAA features, MRI biomarkers, and management.

RECENT FINDINGS

The rate of ICH recurrence in CAA is among the highest of all stroke subtypes. Cortical superficial siderosis (cSS) and cortical subarachnoid hemorrhage (cSAH) are important imaging predictors for recurrent ICH. CAA also causes cognitive problems in multiple domains. In patients with nondemented CAA, the risk of developing dementia is high especially after ICH. CAA pathology probably starts years before the first clinical manifestations. The first signs in hereditary CAA are white matter lesions, cortical microinfarcts, and impaired occipital cerebral vasoreactivity. Visible centrum semiovale perivascular spaces, lobar located lacunes, and cortical atrophy are new nonhemorrhagic MRI markers.

SUMMARY

CAA should be in the differential diagnosis of elderly patients with lobar ICH but also in those with cognitive decline and episodic transient neurological symptoms. Physicians should be aware of the cognitive effects of CAA. In patients with a previous ICH, cSS, or cSAH, anticoagulation should be considered risky. The increasing number of MRI markers may help to discriminate CAA from other small vessel diseases and dementia subtypes.