Risk of Out-of-Hospital Cardiac Arrest in Aged Individuals in Relation to Cold Ambient Temperature　- A Report From North Tochigi Experience.

BACKGROUND: The impact of cold ambient temperature on out-of-hospital cardiac arrest (OHCA) in aged individuals caused by cardiovascular events in indoor environments has not been investigated sufficiently.Methods and Results:We conducted a case-crossover study. The relationship between OHCA caused by cardiovascular events and exposure to minimum temperature <0℃ was analyzed. Conditional logistic regression analysis was performed to estimate the odds ratios for the relationship between exposure to minimum temperature <0℃ and the risk of OHCA. Between January 1, 2011, and December 31, 2015, a total of 1,452 cases of OHCA were documented, and patients were screened for enrollment. A total of 458 individuals were enrolled in this analysis, and were divided into 2 groups of 110 (elderly group: 65-74 years old) and 348 (aged group: ≥75 years old). The aged individuals had a significant increased risk of OHCA after exposure to minimum temperature <0℃ (odds ratio [OR]: 1.528, 95% confidence interval [CI] 1.009-2.315, P=0.045). Cold ambient temperature was an especially significant increased risk for OHCA occurrence for males (OR: 1.997, 95% CI 1.036-3.773, P=0.039) and during winter (OR: 2.391, 95% CI 1.312-4.360, P=0.004) in the aged group. CONCLUSIONS: Cold ambient temperature significantly affected aged individuals (≥75 years old) experiencing an OHCA caused by cardiovascular events in indoor environments.

Single-center experience with the bicarbon bileaflet prosthetic heart valve in Japan.

We analyzed midterm results using the Bicarbon valve in a single center. Forty-four patients had aortic valve replacement (AVR), 48 had mitral valve replacement (MVR), and 13 had both aortic and mitral valve replacement (DVR). The mean age of the 105 patients was 61.2 +/- 11.3 years. The mean follow-up was 1.8 +/- 1.1 years with a cumulative follow-up of 188 patient-years. There were 5 early deaths (4.7%: 4 in the AVR group and 1 in the MVR group) and 5 late deaths (2.7% per patient-year: 3 malignancy, 1 cerebral hemorrhage, 1 myocardial infarction). Survival at 3 years was 91 +/- 4% in the AVR group, 92 +/- 5% in the MVR group, and 66 +/- 23% in the DVR group. The linearized incidence of thromboembolic complications, hemorrhagic complications, and paravalvular leaks in all patients was 1.06 +/- 2.34%, 1.60 +/- 2.53%, and 0.53 +/- 2.22% per patient-year, respectively. No other complications were observed. In conclusion, the Bicarbon prosthetic heart valve has shown excellent clinical results associated with a low incidence of valve-related complications.