VISION: High-Sensitivity Troponin Strongly Linked to Increased Death From Myocardial Injury After Noncardiac Surgery

WASHINGTON, DC—Using high-sensitivity troponin T (hs-TnT) testing in the hours and days after noncardiac surgery may be a simple way of predicting increased risk of early death due to myocardial injury, according to a new study.

The researchers say myocardial injury after noncardiac surgery (MINS) is relatively common and may frequently be overlooked, since as many as 93% of patients in their study had no ischemic symptoms. Most myocardial injury cases occurred within 48 hours after surgery, and one possible explanation for missing them may be that narcotic therapy given after surgery masks cardiac-related symptoms.

Lead author P.J. Devereaux, MD (Population Health Research Institute, Hamilton, Canada), who presented the data today at the American College of Cardiology 2017 Scientific Session, reported that elevations in peak hs-TnT measurements correlated strongly with 30-day mortality and may explain up to 24% of deaths.

“At the moment I think there is very low-lying fruit that we’re ignoring that could actually help a lot of patients,” Devereaux observed.

At Risk but Overlooked

The VISION study included 21,842 patients from 23 centers in 13 countries who underwent elective, urgent, or emergent surgeries occurring at any time including weekends and at night. The most common types of noncardiac surgery were major general (20%) and orthopedic (16%). More than one-third of all patients were considered to be at low surgical risk.

hs-TnT testing was performed 6-12 hours after surgery and on postoperative days 1, 2, and 3.

For the entire cohort, the mortality rate at 30 days was 1.2%. A peak hs-TnT value of < 5 ng/L was considered normal and occurred in 1 in 1,000 patients. Values of 5 to < 14 ng/L and of 14 to < 20 ng/L were associated with small, independent increases in mortality. However, the greatest increases in risk were seen for values of 20 to < 65 ng/L (3% death rate), 65 to < 1,000 ng/L (9% death rate), and ≥ 1,000 ng/L (29.6% death rate). The results were consistent regardless of eGFR and sex.

Additionally, MINS, major bleeding, sepsis, new A-fib, and stroke all were associated with increased 30-day mortality.

Ignoring the Low-Lying Fruit

In a press conference following his presentation, Devereaux said the study represents “the best data we have from a large database.” He believes it is likely that the threshold cutoffs identified by his study are widely applicable to the broader population of patients undergoing noncardiac surgeries.

High-sensitivity troponin assays have been available for years but have only recently gained a stronghold in the United States with the announcement this January that the US Food and Drug Administration issued 501 (k) clearance to the fifth-generation Elecsys Troponin T STAT assay (Roche).

Also speaking in the press conference, Alistair Phillips, MD (Cedars-Sinai Medical Center, Los Angeles, CA), characterized the study as very important work that “has defined a way for these patients to be seen as having a risk of having MINS.”

Devereaux noted that the study sheds light on a general lack of hs-TnT testing, as well as the little direction on medical management when MINS occurs, since most cardiologists are not involved in postoperative care. As for what to do in patients with elevated hs-TnT levels after surgery, he said some studies have shown aspirin and statins may be of value. Patients in whom such therapy should be considered—along with cardiology follow-up—are those with postoperative measures of 20 to 65 ng/L with an absolute change of 5 ng/L, or those with a value of 65 ng/L or greater, he added.

Panelist Athena Poppas, MD (Brown University, Providence, RI), called the study “excellent” and “elegant,” noting that it has “helped define the cutoff of the high-sensitivity troponin, and I think that will be clinically useful and change practice.”