Yuji Konishi

Characterization of predictors of in-hospital cardiac complications of takotsubo cardiomyopathy: Multi-center registry from Tokyo CCU Network

BACKGROUND Takotsubo cardiomyopathy (TC) is an acute cardiac syndrome characterized by transient left ventricular dysfunction and relatively good prognosis after discharge. However, cardiac complications during hospitalization remain to be fully determined. We attempted to determine features characterizing patients with adverse clinical outcome by comparing those with cardiac complication and without cardiac complication during hospitalization. METHODS AND RESULTS We investigated 107 patients with TC from the Tokyo CCU Network database, comprising 67 cardiovascular centers in the metropolitan area during January 1 to December 31, 2010. Cardiac complications were defined as cardiac death, pump failure (Killip grade≥II), sustained ventricular tachycardia or fibrillation (SVT/VF), and advanced atrioventricular block (AVB). Cardiac complications were observed in 41 patients (37 pump failure complicated by 3 cardiac deaths and 2 SVT/VF and 2 AVB without pump failure), and there was no cardiac complication in the remaining 66 patients. There was no difference in age, peak creatinine kinase level, C-reactive protein level and ST elevation on electrocardiogram. Multiple logistic regression analysis showed that white blood cell count (p=0.039) and brain natriuretic peptide (p=0.001) were independent predictors of in-hospital adverse cardiac complications. CONCLUSIONS Cardiac complications are relatively high in patients with TC during hospitalization. High white blood cell count and brain natriuretic peptide level are associated with poor clinical outcome in patients with TC.

Comparison of outcomes after everolimus-eluting stent implantation in diabetic versus non-diabetic patients in the Tokyo-MD PCI study

BACKGROUND Diabetes mellitus (DM), especially in those requiring insulin for treatment, is known to be a risk factor for adverse events after percutaneous coronary intervention using first-generation drug-eluting stents. However, the role of DM in patients treated with everolimus-eluting stents (EES) is less known. The purpose of the present analysis was to evaluate the outcomes of treatment with EES for DM patients both requiring and not requiring insulin, and to compare them with non-DM patients. METHODS Of patients treated with EES in the Tokyo-MD PCI study, an all-comer, multicenter, observational cohort study, we identified 199 insulin-requiring diabetics (IRDM), 575 non-insulin requiring diabetics (NIRDM), and 1092 non-diabetics (non-DM). The main outcomes were major adverse cardiovascular events (MACE) defined as a composite of all-cause death, myocardial infarction, and stroke, and target lesion revascularization (TLR). RESULTS The cumulative incidence of MACE and TLR was significantly greater in patients with IRDM than non-DM [MACE: hazard ratio 1.97, 95% confidence interval (CI) 1.31-2.90, p<0.01; TLR: hazard ratio 3.43, 2.07-5.55, p<0.0001] according to univariate Cox proportional hazards model. After adjusting for confounders using the multivariate Cox proportional hazard model, the risk of IRDM versus non-DM for TLR remained significant (hazard ratio 1.92, 1.10-3.29, p=0.02). The incidence of TLR in NIRDM was slightly greater than that in non-DM according to univariate analysis (hazard ratio 1.65, 1.07-2.54, p=0.02). However, the risk was not statistically different in the multivariate analysis (hazard ratio 1.52, 0.97-2.35, p=0.06). CONCLUSIONS In this all-comer, observational study, the risk of TLR was greater in IRDM compared with non-DM after EES implantation, while the increased risk for TLR from NIRDM did not reach statistical significance.

Adenosine triphosphate-induced atrial fibrillation: the clinical significance and relevance to spontaneous atrial fibrillation

PurposeAdenosine triphosphate (ATP) frequently triggers atrial fibrillation (AF), but the clinical significance of this phenomenon is unknown. The purpose of this study was to reveal the relevance between spontaneous AF and ATP-induced AF.MethodsIn 81 AF patients undergoing pulmonary vein isolation (PVI), we injected 20 mg of ATP before PVI, and recorded triggering sites of the AF induced. We also injected 20 mg of ATP in 44 patients receiving ablation for atrioventricular reciprocating tachycardia (AVRT).ResultsATP provoked AF in 24 (29.6 %) of the 81 PVI patients and atrial ectopic beats in a further 48 (59.3 %). The trigger site of the AF was in the PV and the right atrium in 22 (91.7 %) and 2 patients, respectively. In 14 of those 24 patients, spontaneous AF arose from the same triggering site as the ATP-induced AF. In the 48 patients with ATP-provoked ectopic beats, spontaneous AF arose from the same site in 13. Conversely, among the 34 patients demonstrating spontaneous AF initiation, AF or ectopic beats were provoked by ATP from the same site in 14 (41.2 %) and 13 patients (38.2 %), respectively. ATP provoked AF in only 2 (4.5 %) of the AVRT patients. In summary, ATP provoked AF or atrial ectopic beats in 88.9 % of PVI patients, 36.1 % of whose triggering sites matched that of the spontaneous AF, while 79.4 % of spontaneous AF trigger sites matched ATP-provoked AF or ectopic beat sites. ConclusionsATP-induced AF was strongly associated with clinical AF, and ATP is useful for identifying arrhythmogenic sites.

Usefulness of Implantable Cardioverter-Defibrillators in Patients with Coronary Spasm and Inducible Ventricular Arrhythmia

Background: Coronary artery spasm is one of causes of life-threatening ventricular arrhythmia and sudden cardiac death, but indication of implantable cardioverter-defibrillators (ICDs) is controversial. Our aim is to reveal the clinical features and long term prognosis of vasospastic angina patients with ventricular arrhythmia. Methods: We investigated retrospectively 31 survivors of cardiac arrest with implantation of ICDs. All patients underwent coronary angiography, and without ischemic findings we performed acetylcholine provocation test and electrophysiological study. Results: In 5 patients (56.6±15.7 years old, 5 males) multi-vessel spasm was induced by acetylcholine injection, and in 4 patients of them ventricular fibrillation were inducted by right ventricular 3 extrastimuli, and in 1 patient ventricular tachycardia was inducted by right ventricular 2 extrastimuli. All patients were treated with calcium channel blocking agents, isosorbide and antiarrhythmic drug. During mean follow up of 37±16.9 months (between 25 to 66 months), 2 patients received appropriate ICD shocks to ventricular fibrillation respectively in 10 and 14 months after implantation. One patient had a saddle-back-type ECG abnormality, and in another patient ventricular tachycardia was easily induced by right ventricular 2 extrastimuli. Conclusion: In patients with coronary spasm and inducible ventricular arrhythmia ICDs is useful to prevent sudden cardiac death.