Hirokazu Sato

Favorable outcomes of patients with vasospastic angina associated with cardiac arrest

BACKGROUND The long-term survival of vasospastic angina (VSA) patients is generally good, so long as they remain on calcium channel blockers (CCBs) and avoid smoking. However, the pathogenesis, appropriate treatments, and prognosis of VSA associated with cardiac arrest remain unclear. This study aimed to elucidate the clinical features and long-term outcomes of patients with VSA associated with cardiac arrest. METHODS AND RESULTS Eighteen consecutive patients with VSA associated with cardiac arrest [13 patients resuscitated after out-of-hospital cardiac arrest (OHCA) and 5 resuscitated after in-hospital-cardiac arrest] were retrospectively analyzed. Sixteen of the eighteen patients were smokers. None had other cardiac diseases possibly causing cardiac arrest. Although 1 patient resuscitated after OHCA later died of cerebral hypoxia, the remaining 17 were discharged without complications. One patient died of cancer 50 months after resuscitation. The other 16 patients are still alive and none have shown ventricular arrhythmias, syncope, or cardiac arrest during a mean follow-up of 67 months. All are treated with long-acting CCBs/nitrates and successfully quit smoking. Six patients received implantable cardioverter defibrillators (ICD). However, none demonstrated any ventricular arrhythmias and appropriate ICD actuation was achieved. CONCLUSION Appropriate medical treatment can achieve favorable long-term outcomes even for patients with VSA associated with cardiac arrest.

Fluctuation phenomena below the superconducting transition

The fluctuation propagator for the superconducting order parameter belowTc is derived for a gapless superconductor. The fluctuation of the order parameter consists of two distinct modes: the fluctuations of the phase and the modulus of the order parameter. The former fluctuation obeys a phononlike dispersion, while the latter fluctuation is described by a damping diffusion type equation. The present theory gives an account of the fluctuation-induced Josephson effect belowTc observed recently by Carlson and Goldman.

Differentiating between comatose patients resuscitated from acute coronary syndrome-associated and subarachnoid hemorrhage-associated out-of-hospital cardiac arrest.

BACKGROUND Upon initial evaluation in the emergency department (ED), it is often difficult to differentiate between comatose patients resuscitated following acute coronary syndrome (ACS)-associated and subarachnoid hemorrhage (SAH)-associated out-of-hospital cardiac arrest (OHCA). We assessed the clinical differences between resuscitated comatose ACS-OHCA and SAH-OHCA patients during initial evaluation in the ED. METHODS Data of 1259 consecutive OHCA patients were analyzed retrospectively. Of these, 23 resuscitated comatose ACS-OHCA patients and 20 resuscitated comatose SAH-OHCA patients were included in the final analysis. Clinical data obtained during initial evaluation in the ED were compared between groups. RESULTS Pulseless electrical activity (PEA) or asystole as the initial cardiac rhythm, female gender, and preserved left ventricular ejection fraction (≥50%) on the echocardiogram were significantly more common in the SAH-OHCA group (p<0.05 each). Although ST-T abnormalities suggesting myocardial damage (ST elevation and/or ST depression) were noted in most patients in both groups via 12-lead electrocardiogram (95%, ACS-OHCA group; 85%, SAH-OHCA group, p=0.50), reciprocal ST depression was significantly more often absent in the SAH-OHCA group (p=0.025). Initial PEA/asystole and presence of 1 other factor was sufficient to differentiate SAH-OHCA patients from ACS-OHCA patients (100% sensitivity, 91% specificity, 95% accuracy). CONCLUSIONS Initial ED evaluation is sufficient to differentiate between comatose ACS-OHCA and SAH-OHCA patients prior to further diagnostic work-up (e.g. emergent coronary angiography and head computed tomography).

Prevalence and characteristics of idiopathic right ventricular outflow tract arrhythmias associated with J-waves

AIM The arrhythmogenic relationship between the presence of J-waves during sinus rhythm and idiopathic ventricular tachycardia (VT) or pre-mature ventricular contractions (PVCs) originating from the right ventricular outflow tract (RVOT) has not been reported. The aim of this study was to investigate the prevalence and characteristics of idiopathic RVOT-VT/PVCs associated with J-waves. METHODS AND RESULTS The study enrolled 138 consecutive idiopathic RVOT-VT/PVC patients undergoing radiofrequency catheter ablation (RFCA) and 276 age- and gender-matched control subjects. The prevalence of J-waves was assessed in each cohort, and the clinical and electrophysiological data were compared between the RVOT-VT/PVC patients with J-waves (J-RVOT-VT/PVC group) and those without (non-J-RVOT-VT/PVC group). J-waves were more common among patients with idiopathic RVOT-VT/PVCs than among the matched control subjects (40 vs. 16% P < 0.001). The J-RVOT-VT/PVC group had a higher incidence of sustained VT (25 vs. 5%, P < 0.01), shorter VT cycle length (302 ± 57 vs. 351 ± 58 ms, P < 0.001), and more episodes of syncope (25 vs. 2%, P < 0.001) than did the non-J-RVOT-VT/PVC group. However, no patients demonstrated any ventricular fibrillation (VF) or cardiac sudden death in either group. CONCLUSIONS There was a high prevalence of J-waves in the idiopathic RVOT-VT/PVC patients referred for RFCA. Although patients with idiopathic RVOT arrhythmias associated with J-waves might have a more enhanced arrhythmogenicity than those without J-waves, the significance of those J-waves was limited in terms of the prognosis and VF.

Resuscitated out-of-hospital cardiac arrest with normal postresuscitation 12-lead electrocardiography.

A 50-year-old man experienced ventricular fibrillation in the early morning. A 12-lead electrocardiogram obtained immediately after resuscitation showed normal findings. However, an emergent coronary angiogram revealed the acute thrombotic obstruction in the high lateral branch. Following emergent percutaneous coronary intervention was successfully implemented. During observation in the intensive care unit, the patient developed spontaneous prominent ST elevation in the inferior leads, third-degree atrioventricular block, and cardiogenic shock. Atropine and isosorbide dinitrate administration quickly resolved the ST elevation and atrioventricular block. The patient was able to be discharged without cerebral and cardiac dysfunction. The present case gives an important suggestion for the postresuscitation care strategy.

Configuration of Materially Retained Carbon in Our Society: A WIO-MFA-Based Approach for Japan

To achieve the goals of Paris Agreement, global society is directing much effort in substantially reducing greenhouse gas (GHG) emissions. In addition to energy-related efforts, prevention of carbon release into the atmosphere with carbon capture and storage (CCS) and/or utilization of biomass resources is considered indispensable to achieving the global objective. In this study, considering carbon-containing goods as carbon reservoirs in our society similar to forests and reservoirs enabling CCS, the flow of materially utilized carbon was quantified by input-output-based material flow analysis (IO-MFA). As a result, in 2011, 6.3 Mt-C of petroleum-derived carbon and 7.9 Mt-C of wood-derived carbon were introduced to the Japanese society as end-use products (e.g., automobiles and constructions) in various forms (e.g., plastics and synthetic rubbers). The total amount (14.2 Mt-C) corresponded to 4.1% (52.1 Mt-CO2) of annual CO2 emission in Japan in 2011. Subsequently, by referring to the technology that can treat carbon in the target forms in end-of-life products, the recoverability of carbon as a material has been discussed with respect to each form and end-use of carbon. By numerically showing the necessity and potential of implementing appropriate technologies, this study provides scientific direction for policymakers to establish a quality carbon cycle in our society.

Differences between cardiac memory T wave changes after idiopathic left ventricular tachycardia and ischemic T wave inversion induced by acute coronary syndrome

BACKGROUND Cardiac memory (CM) after idiopathic left ventricular tachycardia (ILVT) mimics ischemic T wave inversion (TWI) induced by acute coronary syndrome (ACS). We aimed to establish electrocardiography criteria for differentiating the CM from ischemic TWI. METHODS AND RESULTS We evaluated 16 ILVT and 48 ACS patients. We identified TWI after ILVT in 9/16 patients (CM group), typically in leads II, III, aVF, aVR, and V4-6. The characteristics of CM were similar to TWI induced by ACS involving right coronary artery, but the CM group had more TWI in V4 and shorter QTc. The criteria of (1) positive T in aVL, (2) negative or isoelectric T in II, and (3) negative T in V4-6 or (4) QTc <430ms were 100% sensitive and 96% specific for the CM group. CONCLUSION CM after ILVT can be differentiated in most cases from ischemic TWI by the distribution of TWI and the QTc.

His-Purkinje system-related incessant ventricular tachycardia arising from the left coronary cusp

We describe the case of a 23‐year‐old woman who had His‐Purkinje system‐related incessant ventricular tachycardia with a narrow QRS configuration. The ventricular tachycardia was ablated successfully in the left coronary cusp where the earliest endocardial activation had been recorded. We hypothesize that a remnant of the subaortic conducting tissue was the source of the ventricular arrhythmias.