Activation of the renin-angiotensin-aldosterone system (RAAS) results in vasoconstriction, muscular (vascular and cardiac) hypertrophy and fibrosis. Established arterial stiffness and cardiac dysfunction are key factors contributing to subsequent cardiovascular and renal complications. Blockade of RAAS has been shown to be beneficial in patients with hypertension, acute myocardial infarction, chronic systolic heart failure, stroke and diabetic renal disease. An aggressive approach for more extensive RAAS blockade with combination of two commonly used RAAS blockers [ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs)] yielded conflicting results in different patient populations. Combination therapy is also associated with more side effects, in particular hypotension, hyperkalaemia and renal impairment. Recently published ONTARGET study showed ACEI/ARB combination therapy was associated with more adverse effects without any increase in benefit. The Canadian Hypertension Education Program responded with a new warning: 'Do not use ACEI and ARB in combination'. However, the European Society of Cardiology in their updated heart failure treatment guidelines still recommended ACEI/ARB combo as a viable option. This apparent inconsistency among guidelines generates debate as to which approach of RAAS inhibition is the best. The current paper reviews the latest evidence of isolated ACEI or ARB use and their combination in cardiovascular diseases, and makes recommendations for their prescriptions in specific patient populations.

Background: Left atrial appendage (LAA) occlusion is an alternative to anticoagulation for stroke prevention in patients with atrial fibrillation. Accurate device sizing is crucial for optimal outcome. Patient-specific LAA models can be created using three-dimensional (3D) printing from 3D transesophageal echocardiographic (TEE) images, allowing in vitro model testing for device selection. The aims of this study were to assess the association of model-based device selection with procedural safety and efficacy and to determine if preprocedural model testing leads to superior outcomes. Methods: In 72 patients who underwent imaging-guided LAA occlusion, 3D models of the LAA were created from 3D TEE data sets retrospectively (retrospective cohort). The optimal device determined by in vitro model testing was compared with the actual device used. Associations of model-match and model-mismatch device sizing with outcomes were analyzed. In another 32 patients, device selection was prospectively guided by 3D models in adjunct to imaging (prospective cohort). The impact of model-based sizing on outcomes was assessed by comparing the two cohorts. Results: Patients in the retrospective cohort with model-mismatch sizing had longer procedure times, more implantation failures, more devices used per procedure, more procedural complications, more peridevice leak, more device thrombus, and higher cumulative incidence rates of ischemic stroke and cardiovascular or unexplained death (P < .05 for all) over 3.0 6 2.3 years after LAA occlusion. Compared with the retrospective imaging-guided cohort, the prospective model-guided patients achieved higher implantation success and shorter procedural times (P < .05) without complications. Clinical device compression (r = 0.92) and protrusion (r = 0.95) agreed highly with model testing (P < .0001). Predictors for sizing mismatch were nonwindsock morphology (odds ratio, 4.7) and prominent LAA trabeculations (odds ratio, 7.1). Conclusions: In patients undergoing LAA occlusion, device size selection in agreement with 3D-printed modelbased sizing is associated with improved safety and efficacy. Preprocedural device sizing with 3D models in adjunct to imaging guidance may lead to superior outcomes.

Circulation Journal Official Journal of the Japanese Circulation Society http://www. j-circ.or.jp ysis yields faster and more reproducible results; and (4) a variety of users (eg, cardiac anesthetists) wants to use the repeatable methodology offered by quantitative methods. Image-processing tools provide characterization of the complex 3D morphology and motion of the MV. Combined with the properties of the imaging modality and knowledge of anatomy, this yields quantitative descriptions that are useful in diagnostic and therapeutic decision-making. This review summarizes the current development and applications of quantitative analysis of the MV morphology using RT3DE. Anatomic Consideration MV LeafletsThe anterior leaflet (AL) is in fibrous continuity with the aortic valve and guards one-third of the anterior mitral annulus. Fine demarcations divide the AL into 3 smaller scallops. The posterior leaflet (PL) is crescent-shaped and spans the posterior n the past 5 years, advances in real-time 3-dimensional echocardiography (RT3DE) have revolutionized the imaging of the mitral valve (MV). Many studies have consistently shown the superiority of 3D transesophageal echocardiography (TEE) over 2D TEE for visualizing MV morphology. 1 RT3DE has become the imaging modality of choice for guiding MV surgery and catheter-based intervention. Currently, RT3D imaging of the MV involves mainly visualization and qualitative interpretation of volume-rendered images. This "qualitative" approach typically involves few quantitative measurements of MV morphology, and is prone to subjectivity that introduces bias, low reproducibility, and high dependency on imaging expertise.Quantitative cardiac imaging has growing importance for several reasons: (1) as imaging becomes more digital, the opportunity will create the need; (2) automated approaches to intervention and surgery design and planning are emerging from the laboratory and entering the clinic; (3) algorithm-driven anal- The mitral valve (MV) has complex 3-dimensional (3D) morphology and motion. Advance in real-time 3D echocardiography (RT3DE) has revolutionized clinical imaging of the MV by providing clinicians with realistic visualization of the valve. Thus far, RT3DE of the MV structure and dynamics has adopted an approach that depends largely on subjective and qualitative interpretation of the 3D images of the valve, rather than objective and reproducible measurement. RT3DE combined with image-processing computer techniques provides precise segmentation and reliable quantification of the complex 3D morphology and rapid motion of the MV. This new approach to imaging may provide additional quantitative descriptions that are useful in diagnostic and therapeutic decision-making. Quantitative analysis of the MV using RT3DE has increased our understanding of the pathologic mechanism of degenerative, ischemic, functional, and rheumatic MV disease. Most recently, 3D morphologic quantification has entered into clinical use to provide more accurate diagnosis of MV disease and for plannin...