Degree of myocardial injury severity may affect survival in COVID-19
The prevalence of myocardial injury in acute COVID-19 is approximately 36%, but its presence was significantly associated with worse outcomes, researchers reported.
Elevated troponin levels, an indicator of myocardial injury, conferred a higher risk for death among patients hospitalized with COVID-19.
According to a report published in the Journal of the American College of Cardiology, patients with confirmed COVID-19 (mean age, 66 years; 60% men; 35% with history of CVD) admitted between Feb. 27 and April 12 who had troponin levels measured within 24 hours of admission were assessed to determine the effect of myocardial injury on .
Troponin and COVID-19 survival
Among 2,736 patients admitted to one of five Mount Sinai Health System hospitals in New York, 36% of patients hospitalized with COVID-19 had elevated troponin concentrations. After adjustment for clinically relevant covariates, patients with troponin concentrations between 0.03 ng/mL and 0.09 ng/mL were at greater risk for death compared with patients with normal concentrations of less than 0.03 ng/mL (adjusted HR = 1.75; 95% CI, 1.37-2.24), the researchers wrote.
Patients with COVID-19 and troponin levels of 0.09 ng/dL or more were at the greatest risk for death (aHR = 3.03; 95% CI, 2.42-3.8) compared with those with normal levels.
Patients with troponin concentrations between 0.03 ng/mL and 0.09 ng/mL were at elevated risk for death or mechanical ventilation compared with patients with troponin less than 0.03 ng/mL (HR = 1.75; 95% CI, 1.44-2.13), and those with levels of more than 0.09 ng/mL were at even greater risk (HR = 2.97; 95% CI, 2.47-3.56).
“The prevalence of myocardial injury as defined by elevated troponins was pretty common. We saw that 36% of patients had elevated troponin concentrations, but we suspected that there was likely an impact of other factors,” Anuradha Lala, MD, assistant professor of cardiology in the Zena and Michael A. Wiener Cardiovascular Institute at the Icahn School of Medicine at Mount Sinai, told Healio. “Even after adjusting for how sick patients were, for all their relevant clinical factors of age, sex, hypertension, diabetes, CVD and BMI, even small amounts of myocardial injury presenting as mild elevations in troponin were significantly associated with the risk of death. To be specific, those in the mildly elevated category had a 75% increased risk of death. Those with concentrations over 0.09 ng/mL were associated with up to three times increased risk of death.
“We were surprised with the strength of the correlation with the risk of death, despite low levels of troponin. Troponins were elevated, but they were elevated, generally, at low levels. Despite them being at low levels, however, they were significantly associated with risk of death,” Lala said in an interview. “What it means though, is that increased risk of death associated with myocardial injury seems to be more important than CVD history alone.”
Statin use in COVID-19
In other findings, among patients with COVID-19, statin therapy was associated with better survival (HR = 0.57, 95% CI, 0.47-0.69) but use of ACE inhibitors or angiotensin II receptor blockers was not.
“We have to be very cautious in interpreting that because it's subject to bias. There was a protective association with stain use, but not with ACE inhibitors or angiotensin receptor blockers; however, this was not the primary purpose of this analysis,” Lala told Healio. “We know that the benefits of statins in the setting of myocardial injury is well established, but whether statins also confirmed an anti-inflammatory effect or potentially allow for amelioration of endothelial dysfunction, that's been reported in COVID-19 has not been further elucidated.
“It's also possible, just as a caveat, that statin use in hospital is confounded by physician treatment preference,” Lala said in an interview. “A clinician could potentially discontinue a statin in patients who are sicker. You might be picking up on a bias there. Let's say someone's intubated, for example, a physician may stop the statin in this patient. The statin use may actually be representative of something else.”
Insights for COVID-19 triage
Lala said elevated troponin “certainly raises our index of suspicion for worse outcomes. I am very happy to report that our frequency of admissions for COVID-19 are way down, which is not necessarily the case around the country right now. God forbid, if we do have a second wave or even as patients come in now, it does offer insight to think about these patients a little bit differently. But that would have to be tested formally. What it would suggest to me is that if I see a patient who doesn't look that toxic in the emergency room, but does have an elevated troponin, I would think about that patient a little bit more carefully.”