頚動脈狭窄症治療（CEA/CAS）は長期生存に有効か？

抄録

Introduction: According to current guidelines, treatment for carotid stenosis with carotid endarterectomy (CEA) or carotid artery stenting (CAS) should be limited to patients with a life expectancy of ＞3-5 years. We aimed to assess the long-term survival after CEA and CAS in our institute and compare the survival rate with previous studies and the general Japanese population.

Methods: Between August 2006 and October 2016, 297 consecutive carotid revascularizations with either CEA (n=178) or CAS (n=119) were performed in our institute. The initial treatment was regarded as the starting point in patients who received treatment by bilateral carotid artery stenosis or retreatment. The final examinations were performed in December 2017. Therefore, only the patients who had undergone carotid revascularization at least 1 year before this date were included in the current study. Kaplan-Meier survival analysis was performed and a multivariate Cox hazard model was built for the analysis of long-term survival-associated risk factors.

Results: A total of 257 patients (CEA [n=158], CAS [n=99]; mean age, 72.3 ± 7.6 years), including 115 symptomatic patients, were enrolled in the current study with a mean follow-up period of 57 months. The perioperative stroke and death rate (within 30 days) was 2.5% for CEA and 6.1% for CAS. During follow-up, 41 patients (16%) died, with pneumonia (24%), cancer (17%), heart disease (15%) and senility (12%) as the most frequent causes. No death due to stroke occurred. Cumulative 5- and 7-year survival rates of all patients were 88% and 78%, respectively. Kaplan-Meier estimates of the 5-year survival rate were 91% for CEA and 83% for CAS, and those of the 7-year survival rate were 80% for CEA and 75% for CAS (p = 0.009). A Cox proportional hazard regression model showed the independent risk factors related to any death were age (Hazard ratio [HR], 1.07/year [95% CI, 1.03-1.13]; p = 0.003) and CAS (HR, 2.45 [95% CI, 1.30-14.61] compared with CEA; p = 0.006). The presence of symptoms and ischemic heart disease was not associated with long-term survival. Mean life-expectancy of an 80-year-old man after CEA was 9.5 years and after CAS was 8.0 years. These figures were not substantially different from the mean life expectancy of an 80-year-old man in the general Japanese population (8.95 years).

Conclusion: The life expectancy of patients in the current study satisfies the current guidelines. The life expectancy of men in the current study did not seem to be substantially different from that of men in the general Japanese population. Long-term survival after CEA and CAS was significantly associated with age and CAS. The inclusion of higher risk patients in the CAS group may have been the reason for CAS being a risk factor.