Bacco Gustavo de, Bacco Mateus W de, Sant'Anna João Ricardo Michelin, Santos Marisa F, Sant'Anna Roberto T, Prates Paulo Roberto, Kalil Renato A K, Nesralla Ivo A
FFFCMPA, Bolsista de Iniciação Científica do IC/FUC-FAPERGS, Porto Alegre, RS, Brasil.
Rev Bras Cir Cardiovasc. 2008 Jul-Sep;23(3):336-43. doi: 10.1590/s0102-76382008000300009.
This study aims to verify the applicability of Ambler's risk score to patients who have undergone implantation of bovine pericardial bioprosthesis at the Instituto de Cardiologia do RGS/FCU. This study also aims to quantify the risk factors.
Retrospective study with 703 patients who had undergone implantation of bovine pericardial bioprosthesis between 1991 and 2005 at the Instituto de Cardiologia do RS. Aortic implant occurred in 392 patients, mitral in 250 and combined in 61. Primary outcome was hospital mortality. Characteristics used to estimate risk were: gender, age, body mass index (BMI), NYHA functional class, left ventricular ejection fraction, valvular lesions, systemic arterial hypertension, diabetes mellitus, renal function, cardiac rhythm, previous cardiac operations, and surgical priority. Univariate and multivariate logistic regression was used to quantify preponderant risk factors by the odds-ratio (OR).
The mortality rate was 14.3%, which was higher than the estimated mortality rate (3%, according to Ambler's mean score of 6, (p<0.01)). Patients who died presented a mean score of 8.26, which was higher than the survivors' average score of 5.68. Characteristics of increased risk were emergency surgery (OR=10.87), dialysis (OR=6.10), and age higher than 80 years (OR=6.10). Our sample indicates an area under the ROC curve of 72.9% (accepted value > 70%).
The mortality predicted in Ambler's score was not reproduced in the observed results. However, the ROC curve provides evidence that this model is applicable. Preponderant risk factors were individualizated.
本研究旨在验证安布勒风险评分在南里奥格兰德州心脏病研究所/联邦大学医院接受牛心包生物假体植入患者中的适用性。本研究还旨在量化风险因素。
对1991年至2005年期间在南里奥格兰德州心脏病研究所接受牛心包生物假体植入的703例患者进行回顾性研究。392例患者植入主动脉瓣，250例植入二尖瓣，61例为联合瓣膜植入。主要结局为住院死亡率。用于评估风险的特征包括：性别、年龄、体重指数（BMI）、纽约心脏协会（NYHA）心功能分级、左心室射血分数、瓣膜病变、系统性动脉高血压、糖尿病、肾功能、心律、既往心脏手术以及手术优先级。采用单因素和多因素逻辑回归通过比值比（OR）来量化主要风险因素。
死亡率为14.3%，高于估计死亡率（根据安布勒平均评分为6时估计为3%，p<0.01）。死亡患者的平均评分为8.26，高于存活患者的平均评分5.68。风险增加的特征包括急诊手术（OR=10.87）、透析（OR=6.10）以及年龄大于80岁（OR=6.10）。我们的样本显示ROC曲线下面积为72.9%（公认值>70%）。
安布勒评分所预测的死亡率在观察结果中未得到重现。然而，ROC曲线提供了该模型适用的证据。主要风险因素已个体化。
