Koji Hanazawa

Comparison of Long-Term Outcome After Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Patients With Unprotected Left Main Coronary Artery Disease (from the CREDO-Kyoto PCI/CABG Registry Cohort-2)

The long-term outcome of percutaneous coronary intervention (PCI) compared to coronary artery bypass grafting (CABG) for unprotected left main coronary artery disease (ULMCAD) remains to be investigated. We identified 1,005 patients with ULMCAD of 15,939 patients with first coronary revascularization enrolled in the CREDO-Kyoto PCI/CABG Registry Cohort-2. Cumulative 3-year incidence of a composite of death/myocardial infarction (MI)/stroke was significantly higher in the PCI group than in the CABG group (22.7% vs 14.8%, p = 0.0006, log-rank test). However, the adjusted outcome was not different between the PCI and CABG groups (hazard ratio [HR] 1.30, 95% confidence interval [CI] 0.79 to 2.15, p = 0.30). Stratified analysis using the SYNTAX score demonstrated that risk for a composite of death/MI/stroke was not different between the 2 treatment groups in patients with low (<23) and intermediate (23 to 33) SYNTAX scores (adjusted HR 1.70, 95% CI 0.77 to 3.76, p = 0.19; adjusted HR 0.86, 95% CI 0.37 to 1.99, p = 0.72, respectively), whereas in patients with a high SYNTAX score (≥33), it was significantly higher after PCI than after CABG (adjusted HR 2.61, 95% CI 1.32 to 5.16, p = 0.006). In conclusion, risk of PCI for serious adverse events seemed to be comparable to that after CABG in patients with ULMCAD with a low or intermediate SYNTAX score, whereas PCI compared with CABG was associated with a higher risk for serious adverse events in patients with a high SYNTAX score.

Very long-term clinical outcomes after radiofrequency catheter ablation for atrial fibrillation: A large single-center experience

AIMS Radiofrequency catheter ablation (RFCA) has become widely used for drug-refractory atrial fibrillation (AF). However, there is a paucity of data on the long-term clinical outcomes after RFCA for AF. The aim of the present study was to investigate the very long-term outcomes after RFCA for AF in a large number of consecutive patients. METHODS AND RESULTS In this retrospective single-center study, we evaluated very long-term follow-up results in 1206 consecutive patients undergoing first RFCA for AF. The primary outcomes were adverse outcomes at 30-day as a safety outcome measure and event-free rates from recurrent atrial tachyarrhythmias as efficacy outcome measures. Final follow-up rate reached 99.3% with a mean follow-up duration of 5.0±2.5years. The incidence of overall 30-day adverse outcomes was 3.6% without death. The 10-year event-free rates from recurrent atrial tachyarrhythmias after the initial and last procedures were 46.9% and 76.4%, respectively. Arrhythmia recurrence occurred most commonly during the first year and decreased beyond 3-year, although it continued to occur at an annual rate of 2.0% and 1.3%, respectively, throughout the 10-year follow-up period. The cumulative 10-year incidences of stroke and major bleeding were 4.2% and 3.5%, respectively, with annual rates of 0.3%. Discontinuation rate of oral anticoagulation at 1-, 3-, and 10-year was 34.6%, 53.4%, 58.0% and 61.9%. CONCLUSIONS RFCA for AF provided favorable very long-term arrhythmia-free survival without much safety concerns. The 10-year rates of stroke and major bleeding were low even with discontinuation of oral anticoagulation in a large proportion of patients.

Thromboembolic stroke after cardioversion with incomplete left atrial appendage closure

Sirs: A 73-year-old man with persistent Atrial Fibrillation (AF) and a CHA2DS2VASc Score of 3 underwent uneventful percutaneous left atrial appendage (LAA) closure (Watchman, 21 mm, Atritech, Inc., Plymouth, Minnesota) guiding fluoroscopy and transesophageal echocardiogram (TEE) in 2011 because of the inability to keep the INR within the therapeutic range (Fig. 1). TEE revealed residual flow into the LAA after implantation and also during follow-up, no flow was seen directly around the device. Warfarin was stopped 6 weeks and clopidogrel 3 months after implantation, aspirin was continued. Due to progressive arrhythmia symptoms, 15 months after implantation, successful electrical cardioversion was performed on aspirin alone after exclusion of intracardiac thrombi with TEE. The following day, the patient developed right-sided weakness and aphasia, cerebral computed tomography (CT) showed ischemia in the territory of the left medial cerebral artery. Repeat analysis of the previous TEE images revealed residual narrow flow (speed [40 cm/s) in the lateral portion of the LAA (Fig. 2). On cardiac CT, the occluder was positioned in one of the two LAA lobes and the other lobe was not occluded (Fig. 3). There was no evidence of intracardiac thrombus. The neurologic symptoms resolved quickly, and oral anticoagulation (Dabigatran, 2 9 150 mg/day) was started. Interventional LAA closure is as effective as oral anticoagulation in patients with non-valvular AF [1–6], and some case reports [7, 8] pointed out that a combined mitral valve treatment and interventional LAA closure in patients with AF and mitral valve disease is effective in reducing thromboembolic complications. In one analysis, residual peri-device flow was not associated with an increased risk of thromboembolism in PROTECT-AF [9]. However, the risk of thromboembolic complications in patients undergoing cardioversion is unknown, and there is no clear evidence that cardioversion can be performed without anticoagulant treatment after mechanical LAA occlusion. In this case, there are several important points: (1) the cause of ischemia was presumably cardiac embolic in origin (although the TEE before cardioversion did not show any thrombus). Therefore, as suggested in the guidelines, effective anticoagulant treatment is mandatory for 4 weeks after cardioversion despite closure of the LAA. The role of residual flow into the LAA after interventional LAA occlusion in increasing the risk of thromboembolic complications after cardioversion is unknown. In addition, thrombi might also evolve in the left atrium cavity due to atrial stunning after cardioversion. (2) The CT (Fig. 3) revealed a more complex 3D anatomy of the LAA, which was not seen with TEE or fluoroscopy (Fig. 1) during the procedure. Therefore, it is recommended to assess LAA anatomy with different two-dimensional views (preferably with 3D) in Electronic supplementary material The online version of this article (doi:10.1007/s00392-014-0724-0) contains supplementary material, which is available to authorized users.

Effect of radiofrequency catheter ablation of persistent atrial fibrillation on the left atrial function: Assessment by 320-row multislice computed tomography

BACKGROUND Atrial fibrillation (AF) increases the left atrial (LA) volume and deteriorates LA function. Whether successful radiofrequency catheter ablation (RFCA) of persistent AF can reverse this process has not been yet established. METHODS Patients with persistent AF undergoing RFCA were evaluated with pre- and post- (at 6-months of follow-up) procedural multislice computed tomography (MSCT). The LA functions were assessed through LA time-volume curves. RESULTS The study population consisted of 44 patients [age 64 (interquartile ranges: 58, 70) years old, 93% male]. Among those, 31 patients (70%) maintained sinus rhythm during the follow-up (no recurrence group; NR group). The remaining 13 patients were classified as the recurrence group (R group). A significant decrease in the minimal and maximal LA volumes was observed in both groups, although this was less pronounced in the R group. Only the NR group had an improvement in the LA expansion index [18% (13, 25) vs. 37% (23, 43), p<0.001], ejection fraction [15% (11, 20) vs. 27% (19, 30), p<0.001] and conduit function [17 ml/m(2) (13, 20) vs. 25 ml/m(2) (20, 34), p<0.001]. An improvement of LV function was also observed only in the NR group. CONCLUSIONS LA anatomical and functional reverse remodeling after RFCA of persistent AF was demonstrated by MSCT during follow-up, which was more pronounced in patients without AF recurrence.

A case of significantly increased mitral regurgitation early after atrial septal defect closure

We report a rare case in which mitral regurgitation (MR) was exacerbated to a severe level early after atrial septal defect (ASD) closure, even though the female patient had preoperatively mild MR and mild changes in mitral valve (MV) and sinus rhythm. The mechanism of increased MR was considered as poor coaptation and tethering of the MV due to the restricted motion of the posterior leaflet in addition to geometric changes of the left ventricle (LV) after ASD closure.

Successful radiofrequency catheter ablation assisted by the CartoSound® system for outflow tract origin nonsustained ventricular tachycardia in a patient with a severely deformed thorax

We report the case of a 72‐year‐old man with a nonsustained ventricular tachycardia and a history of palpitations. He had a severely deformed thorax since childhood due to spinal caries. An integrated computed tomography image of the outflow tract region from the CartoSound® system revealed the detailed anatomical information around the origin of the tachycardia and that the left anterior descending coronary artery was very close (<10 mm) to the target site. We carefully ablated that site with a 3.5‐mm cooled‐tip catheter while confirming it in the sound view, and succeeded without any complications.