on behalf of the Japanese Coronary Spasm Association Background-Coronary artery spasm plays an important role in the pathogenesis of ischemic heart disease; however, its role in sudden cardiac death remains to be fully elucidated. We examined the clinical characteristics and outcomes of patients with vasospastic angina (VSA) in our nationwide multicenter registry by the Japanese Coronary Spasm Association. September 2007 and December 2008, 1429 patients with VSA (male/female, 1090/339; median, 66 years) were identified. They were characterized by a high prevalence of smoking and included 35 patients who survived out-of-hospital cardiac arrest (OHCA). The OHCA survivors, as compared with the remaining 1394 non-OHCA patients, were characterized by younger age (median, 58 versus 66 years; PϽ0.001) and higher incidence of left anterior descending coronary artery spasm (72% versus 53%, PϽ0.05). In the OHCA survivors, 14 patients underwent implantable cardioverter-defibrillator (ICD) implantation while intensively treated with calcium channel blockers. Survival rate free from major adverse cardiac events was significantly lower in the OHCA survivors compared with the non-OHCA patients (72% versus 92% at 5 years, PϽ0.001), including appropriate ICD shocks for ventricular fibrillation in 2 patients. Multivariable analysis revealed that OHCA events were significantly correlated with major adverse cardiac events (hazard ratio, 3.25; 95% confidence interval, 1.39 to 7.61; PϽ0.01). Conclusions-These results from the largest vasospastic angina cohort indicate that vasospasm patients who survived OHCA are high-risk population. Further studies are needed to determine whether implantable cardioverter-defibrillator therapy improves patient prognosis. (Circ Arrhythm Electrophysiol. 2011;4:295-302.) Methods and Results-BetweenKey Words: acetylcholine Ⅲ angina pectoris Ⅲ arrhythmia, cardiac Ⅲ prognosis Ⅲ coronary vasospasm O ut-of-hospital cardiac arrest (OHCA) is a major public health problem. Its estimated number is 300 000 to 400 000 per year in the United States. 1 A prospective study showed an incidence of 53 in 100 000 per year, with 25% of victims being younger than 65 years. 2 Causes of OHCA are strongly associated with coronary artery disease as evidenced at autopsy, and the survival rate from OHCA still remains to be substantially improved. 1 Importantly, a significant number of OHCA cases remained unexplained if victims have no structural abnormalities (eg, organic coronary stenosis) in the postmortem analysis. 3 This finding strongly suggests that functional abnormalities of the coronary artery are also involved in the pathogenesis of OHCA. 4 Clinical Perspective on p 302Recently, the prevalence of early access to emergency medical service, early bystander cardiopulmonary resuscitation, and early defibrillation has been increasing, with a resultant improvement of the survival rate from OHCA. [5][6][7] The progress of the chain of survival now opens the window to elucidate the underlying mechanisms of patients who surviv...

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To investigate the effect of aging on the renin-angiotensin-aldosterone system, plasma renin substrate concentrations (PRSC); plasma total, active, and inactive renin concentrations (TRC, ARC, and IRC); PRA; and plasma aldosterone concentrations (PAC) were measured simultaneously in 60 normal subjects, 18-84 yr old. PRSC was measured by the addition of excess human renal renin. ARC and TRC after trypsin activation were measured by adding sheep renin substrate; IRC was calculated by subtracting ARC from TRC. The active renin ratio was calculated as follows: ARC/TRC X 100%. PRA and PAC were measured by RIA. There were no significant changes in PRSC, TRC, IRC, and PRA to PAC ratio with aging. Both ARC and active renin ratio fell significantly with aging (r = 0.46 and P less than 0.01; and r = 0.54 and P less than 0.01, respectively). PRA and PAC also tended to decrease with aging (r = 0.35 and P less than 0.01; and r = 0.59 and P less than 0.01, respectively). A significant positive correlation was found between PRA and ARC (r = 0.72; P less than 0.001). PRA was also correlated with PAC. In conclusion, the age-related decrease in PRA is not due to the change in PRSC, but is mainly due to the fall in ARC. Decreased conversion of inactive to active renin might be responsible in part for the reduced ARC in the elderly.