A preoperative blood test may predict cardiac complications risk after surgery

The number of surgical interventions is on the rise and together there is an increase in number of postoperative complications. Of all the patients who undergo various major surgeries such as hip and knee replacements, bowel resections and abdominal aortic aneurysm repair 18 per cent will experience serious cardiac and vascular complications including death within 30 days in the postoperative period.

Hamilton researchers have conducted a study and found that a common cardiac blood test is done before surgery can predict who will experience adverse outcomes after most types of surgery. The VISION study has found that preoperative cardiac blood test, NT-proBNP can predict which patients are at greatest risk of cardiac complications after surgery.

"Any type of surgery has the potential to cause damage to heart tissue, through blood clot formation, long periods of inflammation, or bleeding," said study lead, Dr PJ Deveraux, professor of medicine, cardiologist at Hamilton Health Sciences (HHS) and scientific lead for perioperative research at McMaster University and HHS' Population Health Research Institute (PHRI).

The VISION study looked at whether levels of a cardiac blood test, NT-proBNP, measured before surgery can predict cardiac and vascular complications. Higher levels of NT-proBNP, which can be caused by various anomalies in the cardiac muscle, such as stress, inflammation or overstretch, can help identify which patients are at greatest risk of cardiac complications after surgery.

The study included 10,402 patients aged 45 years or older having non-cardiac surgery with overnight stay from 16 hospitals in nine countries.

"As a result of these findings, doctors can predict who is at greater risk of heart attacks and other negative vascular events after surgery," said Dr Devereaux.

This phase of the VISION study builds upon six years of research studies to understand pre- and post-operative factors that lead to cardiac complications.

"This simple blood test can be done quickly and easily as part of patient's pre-operative evaluation and can help patients better understand their risk of post-operative complications and make informed decisions about their surgery," said first author of the publication, Dr Emmanuelle Duceppe, internist and researcher at the Centre Hospitalier de l'Universite de Montreal (CHUM), PhD candidate in clinical epidemiology at McMaster University, and associate researcher at PHRI. "This blood test is twenty times cheaper than more time-consuming tests such as cardiac stress tests and diagnostic imaging."

Results of this simple blood test may inform the type of surgery the patient will undergo, such as laparoscopic or open surgery, the type of anaesthesia used during surgery and who will require more intense monitoring postoperatively.

Blood test results can also reduce the need for pre-surgical medical consultations for patients that show no risk for cardiac complications.

"Heart injury after non-cardiac surgery is emerging as an important health issue requiring attention. Using CIHR funding, the research group led by PHRI and Dr Devereaux, has clarified the association between an elevation of a common biomarker and the risk of per-operative morbidity and mortality," said Dr Brian H. Rowe, Scientific Director, Institute of Circulatory and Respiratory Health, Canadian Institutes for Health Research.