reops and the complicated business of risk factors
reops and the complicated business of risk factors
I went to see the surgeon who will be doing my valve replacement in a few weeks, and asked him about an increased mortality rate on re-ops. He said (and I assume he meant in his hands, at this hospital) the mortality rates have come down from 5-6% to 2-3%. So, sounds like as conditions for surgery improve, so do the outcomes, at least at major heart surgery centers.
However, most journal articles I read about reoperative risks have information describing all of the most influential risk factors, so it's important to remember that statistics are for patient populations, and only serve as a predictive tool for individuals (that means any statistic quoted may have absolutely nothing to do with your own individual experience). It does seem that previous open heart surgery is a risk factor for subsequent surgical outcomes.
Here's an example:
Ann Thorac Surg. 2004 Jun;77(6):1966-77. Related Articles, Links
Multivariable prediction of in-hospital mortality associated with aortic and mitral valve surgery in Northern New England.
Nowicki ER, Birkmeyer NJ, Weintraub RW, Leavitt BJ, Sanders JH, Dacey LJ, Clough RA, Quinn RD, Charlesworth DC, Sisto DA, Uhlig PN, Olmstead EM, O'Connor GT; Northern New England Cardiovascular Disease Study Group and the Center for Evaluative Clinical Sciences, Dartmouth Medical School.
Dartmouth Medical School, Hanover, New Hampshire 03756, USA.
BACKGROUND: Predicting risk for aortic and mitral valve surgery is important both for informed consent of patients and objective review of surgical outcomes. Development of reliable prediction rules requires large data sets with appropriate risk factors that are available before surgery. METHODS: Data from eight Northern New England Medical Centers in the period January 1991 through December 2001 were analyzed on 8943 heart valve surgery patients aged 30 years and older. There were 5793 cases of aortic valve replacement and 3150 cases of mitral valve surgery (repair or replacement). Logistic regression was used to examine the relationship between risk factors and in-hospital mortality. RESULTS: In the multivariable analysis, 11 variables in the aortic model (older age, lower body surface area, prior cardiac operation, elevated creatinine, prior stroke, New York Heart Association [NYHA] class IV, congestive heart failure [CHF], atrial fibrillation, acuity, year of surgery, and concomitant coronary artery bypass grafting) and 10 variables in the mitral model (female sex, older age, diabetes, coronary artery disease, prior cerebrovascular accident, elevated creatinine, NYHA class IV, CHF, acuity, and valve replacement) remained independent predictors of the outcome. The mathematical models were highly significant predictors of the outcome, in-hospital mortality, and the results are in general agreement with those of others. The area under the receiver operating characteristic curve for the aortic model was 0.75 (95% confidence interval [CI], 0.72 to 0.77), and for the mitral model, 0.79 (95% CI, 0.76 to 0.81). The goodness-of-fit statistic for the aortic model was chi(2) [8 df%] = 11.88, p = 0.157, and for the mitral model it was chi(2) [8 df] = 5.45, p = 0.708. CONCLUSIONS: We present results and methods for use in day-to-day practice to calculate patient-specific in-hospital mortality after aortic and mitral valve surgery, by the logistic equation for each model or a simple scoring system with a look-up table for mortality rate.
Sorry for all the details, but I couldn't find ANY simple answers on this topic.
Patty
