Ngaage Dumbor L, Cowen Michael E, Cale Alexander R
Castle Hill Hospital, Kingston-Upon-Hull, East Yorkshire, United Kingdom.
Eur J Cardiothorac Surg. 2009 Feb;35(2):235-40. doi: 10.1016/j.ejcts.2008.10.043. Epub 2008 Dec 11.
Cardiac surgery is higher risk in the elderly. It has been suggested that preoperative left ventricular systolic dysfunction (LVSD) and cardiopulmonary bypass (CPB) affect elderly and young patients differently. This study investigates the predictive risk of preoperative LVSD and CPB time for operative mortality in the two groups of patients.
We reviewed the data for 2616 consecutive patients aged >/=70 years and 4078 young patients who had coronary artery bypass grafting (CABG) and/or valve surgery between March 1998 and January 2007. Subgroups defined by severity of LVSD (ejection fraction >0.50 [mild], 0.31-0.50 [moderate] and </=0.30 [severe]) were analysed. Logistic regression models were constructed to identify risk factors among elderly and young patients.
Elderly patients were higher risk and more often underwent valve operation. Moderate and severe LVSD were present in 22% (n=566) and 6% (n=155) of elderly compared to 18% (n=739) and 5% (n=215) of young patients (p=0.001). Operative mortality for CABG was higher in elderly patients with mild (2.3% vs 0.7%, p<0.0001), moderate (4.7% vs 2.3%, p=0.04) and severe LVSD (13.5% vs 8.8%, p=0.01). Although CPB times for similar procedures were equivalent for the two groups, procedure-specific mortality rates were higher among elderly patients for all operations. Whereas age (odds ratio [OR] 1.09, 95% confidence interval [CI] 1.03-1.15, p=0.002) and CPB time (OR 1.01, 95% CI 1.0-1.02, p<0.0001) were predictors for operative mortality for the elderly, they (age [OR 1.0, 95% CI 0.96-1.05, p=0.87], CPB time [OR 1.0, 95% CI 1.0-1.01, p=0.17]) were not for young patients. Moderate LVSD was a risk factor for young patients (OR 3.01, 95% CI 1.45-6.26, p=0.003) but not for the elderly (OR 1.33, 95% CI 0.77-2.29, p=0.30).
Differences in the significance of risk factors between elderly and young patients contribute to the disproportionate operative mortalities. Our data showed that age and CPB duration increased the risk of operative mortality only in the elderly, but the impact of moderate, unlike severe, LVSD was tempered. Further studies are warranted to investigate more biocompatible bypass systems in elderly patients, and if current risk stratification should, perhaps, be revised for elderly patients.
心脏手术在老年人中风险更高。有人提出，术前左心室收缩功能障碍（LVSD）和体外循环（CPB）对老年患者和年轻患者的影响不同。本研究调查两组患者术前LVSD和CPB时间对手术死亡率的预测风险。
我们回顾了1998年3月至2007年1月期间连续2616例年龄≥70岁患者和4078例年轻患者进行冠状动脉旁路移植术（CABG）和/或瓣膜手术的数据。分析了根据LVSD严重程度（射血分数>0.50[轻度]、0.31 - 0.50[中度]和≤0.30[重度]）定义的亚组。构建逻辑回归模型以确定老年患者和年轻患者中的危险因素。
老年患者风险更高，且更常接受瓣膜手术。老年患者中中度和重度LVSD分别占22%（n = 566）和6%（n = 155），而年轻患者中分别占18%（n = 739）和5%（n = 215）（p = 0.001）。轻度（2.3%对0.7%，p<0.0001）、中度（4.7%对2.3%，p = 0.04）和重度LVSD（13.5%对8.8%，p = 0.01）的老年CABG患者手术死亡率更高。尽管两组类似手术的CPB时间相当，但所有手术中老年患者的特定手术死亡率更高。年龄（比值比[OR]1.09，95%置信区间[CI]1.03 - 1.15，p = 0.002）和CPB时间（OR 1.01，95% CI 1.0 - 1.02，p<0.0001）是老年患者手术死亡率的预测因素，但对年轻患者而言（年龄[OR 1.0，95% CI 0.96 - 1.05，p = 0.87]，CPB时间[OR 1.0，95% CI 1.0 - 1.01，p = 0.17]）并非如此。中度LVSD是年轻患者的危险因素（OR 3.01，95% CI 1.45 - 6.26，p = 0.003），但不是老年患者的危险因素（OR 1.33，95% CI 0.77 - 2.29，p = 0.30）。
老年患者和年轻患者危险因素的重要性差异导致了不成比例的手术死亡率。我们的数据表明，年龄和CPB持续时间仅增加老年患者的手术死亡风险，但中度LVSD（与重度不同）的影响有所缓和。有必要进一步研究以调查老年患者中更具生物相容性的体外循环系统，以及当前的风险分层是否可能需要针对老年患者进行修订。
