Heart Failure Risk with Non-Cardiac Surgery
Abstract & Commentary
By Michael H. Crawford, MD
Source: Xu-Cai Yo, et al. Outcomes of patients with stable heart failure undergoing elective noncardiac surgery. Mayo Clin Proc. 2008;83:280-288.
Risk prediction algorithms for non-cardiac surgery and therapeutic trials have focused on the prevention of myocardial ischemic events. Although heart failure is believed to confer an adverse risk, there is little information about the outcomes of elective non-cardiac surgery in patients with stable compensated heart failure. Thus, a group from the Cleveland Clinic studied 557 consecutives patients with a history of heart failure undergoing major elective non-cardiac surgery, who had no clinical signs of overt heart failure. They were compared to a no history or signs of heart failure control group of over 10,000 patients for the primary end point of one-month mortality. There were 192 patients with systolic heart failure (EF < 40%) and 365 with preserved systolic function. Of course, the heart failure patients were older, sicker, and on more medications than the controls. The heart failure group had an increased one-month mortality of 1.3% vs 0.4% for the controls (P = .009). There was a higher one-month readmission rate for the heart failure patients (18% vs 9%, P < .001). There was no difference in outcomes at one month for the two types of heart failure. At one year, there was a significant difference in mortality between the two types of heart failure and controls, with preserved EF patients having a better prognosis among the heart failure patients. A propensity analysis to account for comorbid conditions markedly attenuated the mortality differences (P = .43), but hospital length-of-stay and readmission rates continued to be higher in the heart failure groups. Xu-Cai Yo and colleagues concluded that patients undergoing major elective non-cardiac surgery and a history of stable compensated heart failure had low perioperative mortality rates, but were likely to have increased length-of-stay and higher readmission rates than propensity matched controls.
Commentary
The most interesting finding in this study is the low 30-day mortality rate in stable heart failure patients (< 2%), regardless of EF. The reason for this is not clear from this retrospective study, but some possibilities come to mind. Therapy of heart failure has improved greatly in the last decade, with most patients on a beta blocker and other potent agents. Also, there is an increasing number of patients with heart failure and preserved systolic function (two-thirds of the patients in this study) who have generally better long-term prognoses. However, the patients analyzed for this study were derived from a preoperative evaluation clinic which included few patients having vascular or thoracic surgery. Thus, patients undergoing higher risk surgery were underrepresented. Little detail was provided about the types of surgery the patients had, so relative risk of types of surgery is not known. Presumably thoracic or vascular surgery would result in higher event rates, possibly raising the mortality rate over 2%. In summary, based upon this study, well-compensated patients with a history of heart failure, regardless of EF, can be quoted a < 2% 30-day mortality rate for major abdominal, head, or non vascular surgery. Vascular and thoracic surgery may pose a higher risk of 2% or more. Length of stay and readmission in 30 days will be higher probably because of heart failure decompensation or arrhythmias after surgery. Thus, care must be taken with fluid management and tachycardia in the perioperative period to duplicate the excellent results of this study.
Risk prediction algorithms for non-cardiac surgery and therapeutic trials have focused on the prevention of myocardial ischemic events.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
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