Current evidence on dietary pattern and cognitive function.

With global aging population, age-related cognitive decline becomes epidemic. Lifestyle-related factor is one of the key preventative measures. Dietary pattern analysis which considers dietary complexity has recently used to examine the linkage between nutrition and cognitive function. A priori approach defines dietary pattern based on existing knowledge. Results of several dietary pattern scores were summarized. The heterogeneity of assessment methods and outcome measurements lead to inconsistent results. Posteriori approach derives a dietary pattern independently of the existing nutrition-disease knowledge. It showed a dietary pattern abundant with plant-based food, oily fish, lower consumption of processed food, saturated fat, and simple sugar which appears to be beneficial to cognitive health. Despite inconclusive evidence from both approaches, diet and exercise, beneficial for other diseases, remains to be the two key modifiable factors for cognitive function. Large-scale prospective studies in multiethics population are required to provide stronger evidence in the future.

Amiodarone reduces the amount of ablation during catheter ablation for persistent atrial fibrillation.

AIMS: The step-wise approach to catheter ablation for persistent atrial fibrillation (AF) requires considerable substrate modification targeting at complex fractionated atrial electrograms (CFAEs) in addition to pulmonary vein (PV) isolation. An alternative strategy that minimizes the amount of ablation would be desirable. The aim of this study was to investigate whether the use of pre-procedural amiodarone affects: (i) the amount of ablation required to achieve procedural success, and (ii) long-term outcomes. METHODS AND RESULTS: We studied 121 consecutive patients with persistent AF who underwent catheter ablation. The patients were divided into two groups: Group 1, amiodarone (n = 31); Group 2, other antiarrhythmic drugs or rate control (n = 90). All the patients underwent a step-wise ablation procedure beginning with PV isolation, then proceeding with ablation of the CFAEs and linear lesions until sinus rhythm was achieved. Mean left atrial cycle length of AF (AFCL) was recorded at each step. The number of CFAE ablation sites was recorded. The number of CFAE sites in Group 1 was significantly less than that in Group 2 (P = 0.0121). The AFCLs after each step in Group 1 were significantly longer than those in Group 2. The procedure time and the radiofrequency time of CFAE ablation in Group 1 were significantly shorter than that in Group 2 (P = 0.0276 and P = 0.0458, respectively). There was no significant difference between the two groups in early and long-term outcomes. CONCLUSION: Use of pre-procedural amiodarone prolongs AFCL during catheter ablation and reduces the number of CFAE sites requiring ablation to achieve procedural success while maintaining equivalent long-term results.

The use of balloon atrial septostomy to facilitate difficult transseptal access in patients undergoing catheter ablation for atrial fibrillation.

INTRODUCTION: With the increasing number of patients undergoing repeat catheter ablation procedures for atrial fibrillation, it is not uncommon to encounter a fibrotic interatrial septum that resists the conventional manual advancement of the transseptal sheath. Forceful advancement of the transseptal apparatus can reduce fine control and potentially lead to a higher rate of perforation. CASE: We report a case where adjunctive balloon atrial septostomy was used to facilitate transseptal access in a patient with fibrotic interatrial septum. Using a small-caliber angioplasty balloon and under direct fluoroscopic and transesophageal echocardiogram visualization, balloon septostomy was performed with hand inflation until a "waist" was seen. This technique provides a safe way to control the size of the transseptal access created, and allows the passage of a relatively soft-tipped transseptal sheath across a resistive septum. To our knowledge this is the first published use of balloon atrial septostomy during transseptal puncture for left atrium access in a catheter ablation procedure. CONCLUSION: Balloon atrial septostomy should be considered as an alternative technique for safe transseptal cannulation in select patients in the electrophysiology laboratory or other interventional procedures requiring left atrial access or delivery of large-caliber catheters or sheaths.

Statin utilization patterns for the primary prevention of cardiovascular events: a retrospective study in patients with diabetes mellitus in Hong Kong.

BACKGROUND AND OBJECTIVE: In Hong Kong, about 10% of adults 25-74 years of age have diabetes mellitus. The management of dyslipidemia with lipid-lowering agents (LLAs), including HMG-CoA reductase inhibitors (statins) for the primary prevention of cardiovascular complications, has been found to be beneficial. This study examined statin utilization patterns for the primary prevention of cardiovascular events in patients with diabetes mellitus in two public hospitals in Kong Kong; clinical outcomes in patients who received statins for primary prevention were compared with those in patients not treated with any LLAs. METHODS: This was a retrospective study in patients who were diagnosed with diabetes mellitus. Only patients with no prior history of coronary artery disease were included in the study. Utilization patterns of LLAs and the incidences of cardiovascular complications were recorded from 1 January 2002 to 31 December 2003. RESULTS: A total of 222 patient records were reviewed. Only 75/222 (33.8%) of patients with diabetes mellitus received one or more LLAs for the primary prevention of cardiovascular events. Among these patients, only 21% of patients attained target lipid goals. Nearly half of the patients who were not treated with LLAs (n=147) had dyslipidemia problems. The overall incidence of cardiovascular complications in patients treated and not treated with LLAs was 12.2%. Absence of routine screening for cardiovascular risk and sub-optimal utilization and inadequate dosage titration of LLAs were identified as contributory factors towards cardiovascular events in this patient group. CONCLUSION: The current study failed to prove the benefits of LLAs in reducing the risk of first cardiovascular events in diabetic patients. This may have been due to the use of low doses of LLAs and a lack of laboratory monitoring of cholesterol levels. Development and implementation of guidelines may help promote the use of LLAs in primary prevention of cardiovascular complications.

Use of intracardiac echocardiography to guide implantation of a left atrial appendage occlusion device (PLAATO).

BACKGROUND: Over 90% of thrombi in atrial fibrillation (AF) originate from the left atrial appendage (LAA). Patients with contraindications to anticoagulation are potential candidates for LAA occlusion using the Percutaneous Left Atrial Appendage Transcatheter Occlusion system (PLAATO, ev3 Inc., Plymouth, MN). Transesophageal echocardiography (TEE) is typically used to guide implantation. OBJECTIVE: This study sought to examine the utility of intracardiac echocardiography (ICE) in providing adequate imaging guidance as an alternative to TEE during PLAATO implantation. METHODS: The study group consisted of 10 patients who underwent PLAATO implantation with simultaneous TEE and ICE imaging guidance. ICE was used to perform the following tasks typically fulfilled by TEE: (1) verification of the absence of LAA thrombus, (2) identification of the LAA ostial dimension for device sizing, (3) guidance of transseptal puncture, (4) verification of the delivery sheath position, and (5) confirmation of location and stability of device before its irrecoverable release. The ability of ICE to perform these tasks was assessed from three separate positions: the standard right atrial (RA) position, within the coronary sinus (CS), and the right ventricular outflow tract. RESULTS: ICE imaging of the LAA was optimal from within the CS, although imaging from the proximal pulmonary artery provided better visualization of the distal LAA in cross-section. The LAA dimensions, confirmation of the absence of LAA thrombus, proper positioning of the delivery sheath, verification of location and stability of the device obtained by ICE were consistent with findings from TEE. CONCLUSION: Using nonconventional imaging planes, ICE imaging was able to perform the intraprocedural functions provided by TEE during implantation of the PLAATO left atrial appendage occlusion device.

Fungal infection of implantable cardioverter-defibrillators: case series of five patients managed over 22 years.

BACKGROUND: With the increasing use of implantable cardioverter-defibrillators (ICDs), device complications are becoming more common. Fungal-related ICD infections have rarely been reported, and little is known about the presentation, prevalence, and treatment options for these morbid infections. OBJECTIVES: The purpose of this study was to characterize the clinical features, treatment, and outcomes of patients with fungal ICD infections. METHODS: We performed a retrospective review of ICD procedures performed at a single academic center and identified all ICD-related infections managed between 1983 and 2005. RESULTS: Among a total of 3,648 ICD-related procedures performed between 1983 and 2005, we identified 47 (1.3%) cases of ICD infections, of which 5 (0.1%) were due to a fungal pathogen. Fungal infections were more likely to be associated with abdominal devices, to have a local rather than systemic infection, and to have a longer duration from the original implant to presentation. All patients were treated with ICD system explantation and antifungal therapy. CONCLUSION: Fungal infection of ICDs is a rare but serious complication of device implantation that must be treated aggressively with complete hardware explantation and prolonged antifungal therapy. Because most infections are late complications and have indolent onsets, a high level of clinical suspicion is required for early diagnosis.

Impact of the multicenter automatic defibrillator implantation trial on clinical practice.

BACKGROUND: The first multicenter automatic defibrillator implantation trial (MADIT-I) was a landmark study that identified a significant reduction in mortality among high-risk patients with ischemic cardiomyopathy treated prophylactically with an implantable cardioverter defibrillator (ICD), yet the direct and indirect impact of this trial on clinical practice is unknown. METHODS: We performed a retrospective analysis of the 679 patients who underwent primary ICD implantation between 1994 and 2000 at a single academic center. The baseline characteristics of each patient were determined at the time of ICD implantation, and the vital status of all patients was determined as of January 1, 2004. RESULTS: The number of patients who received an ICD based on the MADIT-I criteria increased from 1.4% in 1994 to 6.1% in 2000. An additional 60 patients were identified that met many but not all of the trial criteria and consisted of patients with a history of a recent revascularization or myocardial infarction, syncope, or an ejection fraction >or=35%. The number of patients who received ICDs in this expanded MADIT-I subset also grew from 5.6% in 1994 to 14.6% in 2000. Mortality during a mean follow-up of 4.7 years was significantly higher in the MADIT-I group than in the expanded MADIT-I, or the remaining primary prevention and secondary prevention subsets. CONCLUSION: The MADIT-I has not only led to an increase in the number of patients undergoing prophylactic ICD implantation, but in clinical practice it has also been extrapolated to a broader population that has a different degree of risk than originally studied.