Trial Information

Vascular Events In Noncardiac Surgery Patients Cohort Evaluation (VISION) Study

The increase in elderly patients undergoing surgery, the change in the invasiveness of some
surgical interventions, limitations in the methodology and generalizability of previous
research, and the VISION Pilot Study results highlight uncertainty about the current
incidence of major vascular events and the optimal clinical risk estimation model to predict
these events in patients undergoing noncardiac surgery. There is promising but inconclusive
preliminary evidence that troponin measurements after surgery may allow physicians to avoid
missing perioperative myocardial infarctions and may predict mortality and major vascular
events in the first year following surgery. These considerations provide the impetus for
the large, adequately powered, multicentre, international, prospective cohort study.

We will determine the incidence of major vascular events, the optimal clinical model to
predict major perioperative vascular events, and the extent to which troponin measurements
post surgery can identify myocardial infarctions that are likely to go unrecognized and
predict vascular death at 1 year. We call this study the Vascular events In noncardiac
Surgery patIents cOhort evaluatioN (VISION) Study.

The VISION Study is a prospective cohort study of 40,000 patients who are > 45 years of age,
undergoing noncardiac surgery requiring overnight hospital admission, and receiving a
general or regional anesthetic. Hospitals (including both university and non-university
hospitals) in several countries around the world will recruit patients, over a 2 year
period. Study personnel will evaluate patients prior to surgery, follow patients throughout
their hospitalization, and contact patients at 30 days and 1 year after surgery. All
patients will have troponin T measured post surgery and on the first, second, and third days
after surgery. Outcome adjudicators will adjudicate all major vascular events without
knowledge of a patient's vascular risk factors.

We will also determine if there are associations between any preoperative or postoperative
medications and major perioperative vascular events. We will also determine if there are
associations between any medications started after a major perioperative vascular event and
vascular mortality 1 year after surgery. We will evaluate the 1 year risk of stroke in
patients who do and do not develop atrial fibrillation after surgery and if there is an
association with antiplatelet or warfarin therapy. We will measure N-terminal prohormone
brain natriuretic peptide (NT-proBNP) in 8,000 - 10,000 patients prior to surgery and
determine if NT-proBNP is an independent predictor of major perioperative vascular events.
We will determine the incidence of perioperative new acute renal failure requiring dialysis
and pneumonia and develop models to predict these events.