Anaesthesia and the cardiac patient: the patient versus the procedure.

For patients undergoing elective surgery, the most common cause of significant morbidity and mortality is occurrence of complications related to cardiac disease. It is estimated that approximately one million patients undergoing surgery each year in the USA suffer a perioperative myocardial infarction. This is particularly true for those with previous coronary disease and those facing higher risk surgery. Because of this fact, a great deal of research has focused on assessing cardiac risk before elective surgery. Less attention has been paid to methods of modifying the risk of cardiac complications attending surgery through medication use or other strategies. The risk of cardiac complications engenders a sense of conflict in that the patient perceives surgery as a threatening foe to be overcome: the patient versus the procedure. We would like to change that paradigm, and encourage an appreciation for the risk inherent to the patient, rather than to the procedure itself. That is, preoperative evaluation of the patient’s risk, versus the procedure’s risk. During the past 10–20 years, the assessment of cardiac risk before surgery evolved a great deal. Initially, the focus was on appropriate identification of surgical procedures that carried high risk. The focus then shifted to identifying those patient factors associated with increased risk of cardiac complications during surgery. Several technical advances were made during this time, including the introduction of imaging stress tests to assess cardiac ischaemia, such as dobutamine echocardiogram, dobutamine thallium, and adenosine or dipyridamole thallium testing. All of these modalities have been shown to identify patients at increased risk for cardiac complications of surgery. Cardiac catheterisation has also been used as a screening modality before elective surgery, though this has not been shown to be cost effective, especially given the low overall incidence of severe coronary artery disease. Studies performed during this time period also delineated the clinical factors that identify patients at increased risk of cardiac complications. More recently, efforts have been made to combine both clinical evaluation and testing in the most efficient and appropriate manner to identify patients at risk of cardiac complications. Finally, recent studies have addressed the effectiveness of medications or interventions to decrease risk in high risk patients. Preoperative cardiac evaluation has several goals: c evaluate and assess perioperative cardiac risk, and provide this information to both patient and surgeon for decision making purposes c optimise appropriateness of preoperative testing and/or intervention c to the extent possible, adjust care in order to decrease operative risk c given the prevalence of coronary disease and its complications, assess and intervene to modify long term risks for cardiovascular disease. We discuss below the current state of preoperative cardiac evaluation and interventions to decrease perioperative cardiac risk, and offer an approach to the preoperative assessment and perioperative care of patients with cardiac disease, focusing on risk reduction.