Is informed consent in cardiac surgery and percutaneous coronary intervention achievable?

Medical and legal published work regularly discusses informed consent and patient autonomy before medical interventions. Recent discussions have suggested that Cardiothoracic surgeons' risk adjusted mortality data should be published to facilitate the informed consent process. However, as to which aspects of medicine, procedures and the associated risks patients understand is unknown. It is also unclear how well the medical profession understands the concepts of informed consent and medical negligence. The aims of this study were to evaluate patients undergoing coronary artery bypass surgery (CABG) and percutaneous coronary intervention (PCI) to assess their understanding of the risks of interventions and baseline level of understanding of medical concepts and to evaluate the medical staff's understanding of medical negligence and informed consent.

Patients undergoing CABG or PCI at a tertiary hospital were interviewed with questionnaires focusing on the consent process, the patient's understanding of CABG or PCI and associated risks and understanding of medical concepts. Medical staff were questioned on the process of obtaining consent and understanding of medicolegal concepts.

Fifty CABG patients, 40 PCI patients and 40 medical staff were interviewed over a 6-month period. No patient identified any of the explained risks as a reason to reconsider having CABG or PCI, but 80% of patients wanted to be informed of all risks of surgery. 80% of patients considered doctors obligated to discuss all risks of surgery. One patient (2%) expressed concern at the prospect of a trainee surgeon carrying out the operation. Stroke (40%) rather than mortality (10%) were the important concerns in patients undergoing CABG and PCI. The purpose of interventions was only partially understood by both groups; PCI patients clearly underestimated the subsequent need for repeat PCI or CABG. Knowledge of medical concepts was poor in both groups: less than 50% of patients understood the cause or consequence of an AMI or stroke and less than 20% of patients correctly identified the ratio equal to 0.5%. One doctor (2.5%) correctly identified the four elements of negligence, eight (20%) the meaning of material risk and four (10%) the meaning of causation. Thirty doctors (75%) believed that all complications of a procedure needed to be explained for informed consent. Less than 10% could recognize landmark legal cases.

Patients undergoing both CABG and PCI have a poor understanding of their disease, their intervention, and its complications making the attaining of true informed consent difficult, despite their desire to be informed of all risks. PCI patients particularly were highly optimistic regarding the need for reintervention over time, which requires specific attention during the consent process. Medical staff showed a poor knowledge of the concepts of material risk and medical negligence requiring much improved education of both junior doctors and specialists.