Yoshimori An

Importance of nonpulmonary vein foci in catheter ablation for paroxysmal atrial fibrillation.

BACKGROUND Pulmonary vein (PV) isolation is an established treatment strategy for paroxysmal atrial fibrillation (PAF). However, the recurrence rate of PAF is 8% to 37%, despite repeated procedures, and the catheter ablation strategy for PAF with non-PV foci is unclear. OBJECTIVE The purpose of this study was to assess the PAF ablation strategy for non-PV foci. METHODS The study included 304 consecutive patients undergoing PAF ablation (209 males, age 63.0 ± 10.4 years) divided into 3 groups: group 1 (245 patients) with no inducible non-PV foci; group 2 (34 patients) with atrial fibrillation (AF) originating from non-PV foci and all the foci successfully ablated; and group 3 (25 patients) with AF originating from non-PV triggers, but without all foci being ablated or with persistently inducible AF. RESULTS Mean follow-up period was 26.9 ± 11.8 months, and AF recurrence rates since the last procedure were 9.8%, 8.8%, and 68.0% in groups 1, 2, and 3, respectively. There was no statistically significant difference in recurrence rate between groups 1 and 2 (P = .89); however, there were statistically significant differences between groups 3 and 1 (P <.0001) and groups 3 and 2 (P <.0001). The patients in group 2 had an AF-free outcome to equivalent to those who had PV foci in group 1 (P = .83). CONCLUSION Success rates can be improved for PAF ablation if non-PV foci are detected and eliminated.

Stroke and death in elderly patients with atrial fibrillation in Japan compared with the United Kingdom

Background Data on stroke, mortality and associated comorbidities in elderly patients with atrial fibrillation (AF) in Japan may differ from Western countries. There have been few systematic comparisons between stroke risk profiles and outcomes among community-based elderly (aged ≥75 years) patients with AF in Japan and the UK. Objective and methods We compared clinical characteristics, stroke risk and outcomes among elderly patients with AF from the Fushimi AF Registry (Japan; N=1791) and the Darlington AF Registry (UK; N=1338). Results The Fushimi cohort had a mean age 81.8 (standard deviation (SD) 5.3) years and CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years (double), diabetes mellitus, previous thromboembolism (double), vascular disease, age 65–74 years and female gender) score 4.3 (1.4), whereas the Darlington cohort had a mean age 83.6 (5.7) years and CHA2DS2-VASc score 4.4 (1.4). Over a 12-month follow-up period, observed stroke and mortality rates in Fushimi were 3.4% (n=61) and 11.5% (n=206), while corresponding event rates in the Darlington cohort were 4.4% (n=59) and 14.1% (n=188), respectively. Appropriate use of oral anticoagulation (OAC, essentially a vitamin K antagonist) was <60% in both registries. On multivariable analysis, ethnicity (Japan vs UK) was neither associated with the risk of stroke (OR 0.92, 95% CI 0.63 to 1.36; p=0.69) nor death (OR 0.92, 95% CI 0.80 to 1.27; p=0.92). In a subgroup analysis of elderly patients not receiving OAC (n=1489), a history of stroke was associated with the risk of stroke (OR 2.42, 95% CI 1.39 to 4.12; p=0.002), but not ethnicity (OR 0.86, 95% CI 0.50 to 1.47; p=0.58). Conclusions Elderly (age ≥75 years) patients with AF in both Japan and the UK are at similarly high risk of stroke and death, with OAC still underused in both populations. Ethnicity was not independently associated with the risk of stroke, regardless of OAC use or non-use.

Long-term outcomes of catheter ablation of ventricular tachycardia in patients with structural heart disease

Catheter ablation of ventricular tachycardia (VT) is feasible. However, the long‐term outcomes for different underlying diseases have not been well defined.

Impact of Catheter Ablation for Paroxysmal Atrial Fibrillation in Patients With Sick Sinus Syndrome – Important Role of Non-Pulmonary Vein Foci –

BACKGROUND The clinical efficacy of catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) in patients with sick sinus syndrome (SSS) and the mechanism and predictors of recurrence are not yet completely elucidated. METHODSANDRESULTS Of 963 consecutive patients who underwent PAF ablation during the study period, a total of 108 patients with SSS (SSS group) and 108 matched controls without SSS (non-SSS group) were followed up. During the follow-up period (mean, 32.8±17.5 months), the SSS group had significantly higher AF recurrence rate since the last procedure than the non-SSS group (26.9% vs. 12.0%; P=0.02). The SSS group had significantly higher prevalence of non-pulmonary vein (non-PV) foci than the non-SSS group (25.9% vs. 13.9%; P=0.027). On multivariate analysis congestive heart failure (HR, 13.7; 95% CI: 1.57-119; P=0.02) and non-PV foci (HR, 5.75; 95% CI: 1.69-19.6; P=0.005) were independent predictors of recurrence following CA in the SSS group. In the SSS group, 88 patients had bradycardia-tachycardia syndrome without prior permanent pacemaker implantation. Of these, 6 required pacemaker implantation because of AF and sinus pause recurrence. CONCLUSIONS Patients with SSS are at higher risk of AF recurrence after CA. Non-PV foci are associated with AF recurrence following PAF with SSS.

Lead extractions in patients with cardiac implantable electronic device infections: Single center experience.

Lead extraction using laser sheaths is performed mainly for cardiac implantable electronic device (CIED) infections. However, there are few reports concerning the management of CIED infections in Japan.

Identification of causative organism in cardiac implantable electronic device infections

BACKGROUND The causative organism in cardiovascular implantable electronic device (CIED) infection is usually diagnosed with the cultures from blood, removed leads, and/or infected pocket material. The cultured organism, however, is sometimes different among these samples. METHODS Two hundred sixty patients with CIED infection, who underwent lead extraction between April 2005 and December 2014, were analyzed. More than two blood culture sets, all the extracted leads, and swab culture of the pocket were sent to the laboratory for culture. Among the patients all of whose microbiological examinations were available, we analyzed the causative organism defined as the species detected in at least two different sites. RESULTS All the culture results were available in the 208 patients, showing 69 systemic infections (including 30 cases of infectious endocarditis) and 139 local infections. Blood culture, lead culture, and swab culture were positive in 57 (27%), 169 (81%), and 152 (73%), respectively. Staphylococcus aureus [37% including methicillin-resistant S. aureus (MRSA) (12%)] and coagulase-negative staphylococci (CoNS, 36%) were the most common causative organism, followed by non-staphylococci (23%), and poly-microbial infection (4%). The detection of S. aureus from pocket or removed leads rendered higher predictive value of a causative organism than that of CoNS. The detection of Gram-negative bacteria, fungi, and mycobacteria indicated that it was most likely a causative organism. Gram-positive bacteria excluding Staphylococcus, such as Corynebacterium spp., tended to coexist as a benign organism. CONCLUSIONS The causative organism is mostly S. aureus and CoNS. Detection of S. aureus or Gram-negative bacteria means that it is more likely a causative organism.

Mortality and predictors of appropriate implantable cardioverter defibrillator therapy in Japanese patients with Multicenter Automatic Defibrillator Implantation Trial II criteria

Data regarding long‐term mortality and factors influencing appropriate therapies in Japanese patients with implantable cardioverter defibrillators (ICD), who satisfy the Multicenter Automatic Defibrillator Implantation Trial II (MADIT II) criteria for primary prevention, remain scarce.

Impact of catheter ablation of ventricular tachycardia in patients with prior myocardial infarctions

Catheter ablation can reduce episodes of ventricular tachycardia (VT) after myocardial infarction (MI). However, the optimal endpoint of the ablation procedure remains unclear.

Clinical Features and Prognosis in Patients with Atrial Fibrillation and Prior Stroke: Comparing the Fushimi and Darlington AF Registries

Background Ethnic differences in clinical characteristics, stroke risk profiles and outcomes among atrial fibrillation (AF) patients may exist. We therefore compared AF patients with previous stroke from Japan and the United Kingdom (UK). Methods We compared clinical characteristics, stroke risk and outcomes among AF patients from the Fushimi AF registry who had experienced a previous stroke (Japan; n = 688; 19.7%) and the Darlington AF registry (UK; n = 428; 19.0%). Results AF patients with previous stroke in Fushimi were significantly younger (76.8 and 79.6 years of age in Fushimi and Darlington; p < 0.01) with a lower proportion of females (37.4% vs. 45.1%; p = 0.01) than those from Darlington. Although the CHA2DS2-VASc score was lower in AF patients in Fushimi than those in Darlington (5.18 vs. 5.57; p < 0.01), oral anticoagulation (OAC) was prescribed significantly more frequently in Fushimi (68.3%) than Darlington (61.7%) (p = 0.02). Multivariate logistic regression analysis showed that Japanese ethnicity was associated with a significantly decreased risk of recurrent stroke (OR 0.59. 95% CI 0.36–0.97; p = 0.04) but a significantly increased risk of all-cause mortality (OR 1.76, 95% CI 1.18–2.66; p < 0.01) in AF patients with previous stroke. Conclusions AF patients with previous stroke in the UK were at higher risk of recurrent stroke compared to Japanese patients, but OAC was utilised less frequently. There was a lower risk of recurrent stroke in the secondary prevention cohort from the Fushimi registry, but an increased risk of all-cause mortality.

Clinical Impact of Asymptomatic Presentation Status in Patients With Paroxysmal and Sustained Atrial Fibrillation: The Fushimi AF Registry

BACKGROUND: The clinical characteristics and outcomes of asymptomatic patients with paroxysmal or persistent/permanent atrial fibrillation (AF) are largely unknown. METHODS: The Fushimi AF Registry is a community‐based prospective survey of patients with AF who visited the participating medical institutions in Fushimi‐ku, Japan. We investigated the clinical characteristics and outcomes of asymptomatic vs symptomatic patients in the paroxysmal AF (PAF; n = 1,837) and persistent/permanent (sustained atrial fibrillation [SAF]; n = 1,912) subgroups. RESULTS: In the PAF group, asymptomatic patients were older (asymptomatic vs symptomatic group, 74.1 vs 71.1 years of age; P < .01), more often male (62.1% vs 55.6%; P < .01), and had a higher CHA2DS2‐VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, history of stroke, vascular disease, age 65–74 years, and female sex) score (mean, 3.37 ± 1.73 vs 2.99 ± 1.63; P < .01), whereas the prevalence of major co‐morbidities and CHA2DS2‐VASc scores were comparable in the SAF group. Multivariable analysis indicated that age (≥ 75 years), history of stroke/systemic embolism, male sex, and chronic kidney disease were independent determinants of asymptomatic status in the PAF group, whereas age was nonsignificant in the SAF group. During the follow‐up period, all‐cause mortality was significantly higher (hazard ratio, 1.71 [95% CI, 1.31–2.29]; P < .01) in asymptomatic patients compared with symptomatic patients in the PAF group, whereas it was comparable in the SAF group. CONCLUSIONS: Asymptomatic clinical status is associated with older age, male sex, more co‐morbidities with a higher stroke risk profile, and a higher incidence of all‐cause death in patients with PAF; these characteristics and outcomes were not seen in the SAF group. TRIAL REGISTRY: UMIN Clinical Trials Registry; No.: UMIN000005834; URL: www.umin.ac.jp/ctr/index.htm.