Cardiac injury among hospitalized Covid-19 patients tied to higher risk of death in new study

Most of the people with the novel coronavirus aren't dying, but the disease can be lethal to some. CNN's Elizabeth Cohen explains how the virus can become deadly. Watch the latest videos on Covid-19.

Posted: Mar 27, 2020 12:00 PM
Updated: Mar 27, 2020 12:00 PM

Heart injury could be a common condition in patients hospitalized with Covid-19, according to a new study that also shows it's linked to a greater risk of death among those patients.

The study, published in the medical journal JAMA Cardiology on Wednesday, found that among a group of Covid-19 patients hospitalized in Wuhan China, 19.7% suffered cardiac injury, which was found to be a risk factor for dying in the hospital.

Cardiac injury, also referred to as myocardial injury, occurs when there is damage to the heart muscle, and such damage can occur when blood flow to the heart is reduced -- which is what causes a heart attack.

Cardiac damage and higher risk of early death

The new study, conducted from January to February, included data on 416 adults who were confirmed to have Covid-19 and were hospitalized at Renmin Hospital of Wuhan University in China.

The data showed that 82 of the patients, or 19.7%, had cardiac injury and 334 patients, or 80.3%, did not. Cardiac injury is defined by an elevation of a protein called troponin that can be measured in the blood, according to the American Heart Association. Troponin and other biomarkers were used to identify cardiac injury in the study.

"An elevated troponin doesn't always mean a heart attack but it does mean myocardial injury or heart damage," said Dr. Erin Michos, the associate director of preventive cardiology at Johns Hopkins Medicine in Baltimore, who was not involved in the study.

The data also revealed that the death rate was higher among patients with cardiac injury versus those without: 42 of the patients with cardiac injury, or 51.2%, died versus 15 of those without, or 4.5%.

"We know that cardiac damage is a marker for more mortality," Michos said. "This study clearly showed that even after you account for age and pre-existing cardiovascular disease, there was a still four-fold increased risk of dying. That's really important."

The new study had some limitations, including that the findings are based on observational data, and more research is needed to determine whether similar findings would emerge among a larger and more diverse group of Covid-19 patients.

Though the study showed cardiac injury is a common condition among patients hospitalized with Covid-19, it did not indicate whether Covid-19 directly causes cardiac injury. The mechanism of cardiac injury, or the process in which it occurs, among the patients with Covid-19 remains uncertain, and more evidence is needed to demonstrate whether Covid-19 directly injures the heart, the authors said.

"We need to figure out the mechanism of why do people with evidence of cardiac injury have higher morbidity or mortality? Is it related to the fact that they have underlying conditions that make them more susceptible to dying? Is it a marker of individuals that have a more robust immune response that is leading to heart damage?" said Michos of Johns Hopkins.

This and other studies suggest that those with elevated troponin, which measures cardiac injury, seem to be at a greater risk than when the elevation of other types of markers are present, such as inflammatory markers, Michos said.

The researchers also offered some ideas, writing in the study that people with preexisting cardiovascular diseases might be more susceptible to heart injury induced by Covid-19.

"Approximately 30% and 60% of patients with cardiac injury in the present study had a history of coronary heart disease and hypertension, respectively, which were significantly more prevalent than in those without cardiac injury," the researchers wrote in the study.

Also, acute inflammatory responses due to an infection can lead to reduced blood flow in patients with preexisting cardiovascular diseases, the researchers noted. They wrote that "based on these lines of evidence, we hypothesize that an intense inflammatory response superimposed on preexisting cardiovascular disease may precipitate cardiac injury."

Earlier this month, the American College of Cardiology released clinical guidance for cardiovascular care team professionals treating Covid-19 patients. In that guidance, the ACC noted that, so far, the case fatality rates for Covid-19 patients who also have cardiovascular disease is 10.5% and for those who also have hypertension, it's 6%.

A 'potentially important long-term issue'

The new study findings "make a lot of sense," Kevin Heffernan, director of the Human Performance Laboratory at Syracuse University in New York, who was not involved in the study, wrote in an email on Wednesday.

A separate study published in the New England Journal of Medicine in 2018 found a significant association between respiratory infections, especially influenza, and acute heart attack, he said.

Overall, "this is a solid and important study," said Brooks Gump, the Falk Family Endowed Professor of Public Health at Syracuse University in New York, who was not involved in the study.

When it comes to the public health impacts of Covid-19 and cardiac injury, the study suggests that "two key take-aways are that it's an important marker of those at high-risk for mortality as a consequence of Covid-19 infection and it may be an indicator of future risks associated with the cardiovascular injury from this infection, even if you recover," Gump said.

"Even though they're not dying from that cardiac injury, something about that biomarker is providing some prognostic value beyond other risk factors that were controlled, so it could still be important in terms of identifying high-risk patients that enter the hospital with Covid-19," Gump said.

"The other key here is the potentially important long-term issue," he said. "Many patients who pull through may still have cardiac injury and associated long-term cardiovascular issues as a consequence of Covid-19 infection."

Drs. Chengzhi Yang and Zening Jin, both of Beijing Tiantan Hospital and Capital Medical University in China, co-authored an editorial that published alongside the new study in JAMA Cardiology on Wednesday.

They noted in the editorial that so far there have been only scarce data with respect to cardiovascular complications of Covid-19.

"To date, many patients with COVID-19 are still hospitalized in China and other countries, such as Italy and Iran. Therefore, continued observations of the cardiovascular complications of the disease are needed. In addition, further assessment is needed to identify risk factors for poor prognosis," Yang and Jin wrote. "Emerging as an acute infectious disease, COVID-19 may become a chronic epidemic similar to influenza because of genetic recombination. Therefore, we should be ready for the reemergence of COVID-19 or other coronaviruses."

Minnesota Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 95659

Reported Deaths: 2056
CountyConfirmedDeaths
Hennepin26960930
Ramsey10911320
Dakota7524126
Anoka6092133
Stearns401024
Washington379955
Scott257433
Olmsted244628
Nobles197116
Blue Earth16996
Wright16327
St. Louis160241
Carver14197
Clay138940
Rice13358
Mower13285
Sherburne115014
Kandiyohi10112
Winona88718
Lyon6954
Waseca6698
Benton5523
Steele5472
Freeborn5424
Nicollet54016
Watonwan5284
Crow Wing51618
Todd4952
Chisago4941
McLeod4882
Le Sueur4674
Otter Tail4414
Beltrami4215
Martin40810
Goodhue3659
Itasca32814
Pine3280
Douglas3102
Polk3054
Isanti2971
Becker2802
Carlton2701
Morrison2492
Dodge2390
Cottonwood2250
Pipestone22510
Chippewa2141
Meeker2022
Wabasha1960
Sibley1923
Brown1912
Yellow Medicine1822
Cass1804
Rock1730
Unassigned17052
Redwood1673
Mille Lacs1643
Murray1642
Renville1518
Jackson1481
Faribault1450
Swift1381
Houston1280
Kanabec1258
Roseau1230
Koochiching1223
Fillmore1200
Pennington1191
Lincoln1110
Hubbard1031
Stevens1031
Pope940
Big Stone820
Aitkin801
Wadena690
Wilkin653
Grant614
Lake590
Lac qui Parle581
Norman540
Marshall521
Mahnomen481
Red Lake451
Traverse310
Clearwater270
Lake of the Woods221
Kittson120
Cook60

Iowa Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 85533

Reported Deaths: 1305
CountyConfirmedDeaths
Polk15872262
Woodbury544764
Johnson512627
Black Hawk448990
Linn4010111
Story344417
Dubuque325741
Scott301128
Dallas278538
Pottawattamie211338
Buena Vista199112
Marshall178434
Sioux16183
Wapello133357
Webster125514
Plymouth114121
Clinton112121
Muscatine110855
Crawford10885
Cerro Gordo105721
Warren9566
Jasper83832
Des Moines7848
Marion7637
Henry7434
Tama71331
Carroll6625
Lee6377
Wright5811
Dickinson5276
Boone5078
Bremer4927
Washington45911
Louisa42915
Mahaska41219
Delaware4023
Floyd3493
Jackson3493
Franklin34818
Winneshiek3356
Clay3264
Lyon3264
Hamilton3223
Benton3101
Winnebago30313
Hardin2991
Poweshiek2958
Buchanan2791
Jones2743
Butler2702
Kossuth2700
Shelby2671
Clarke2653
Emmet26510
Allamakee2616
Clayton2523
Chickasaw2500
Sac2500
Cherokee2492
Cedar2461
Guthrie2456
Fayette2222
Harrison2223
Grundy2203
Madison2192
Iowa2091
Palo Alto2020
Humboldt1903
Mitchell1900
Howard1886
Hancock1842
Calhoun1833
Mills1801
Page1700
Cass1682
Osceola1610
Monroe15911
Pocahontas1592
Lucas1566
Monona1531
Jefferson1381
Appanoose1363
Union1353
Taylor1301
Davis1244
Ida1221
Fremont1180
Van Buren1141
Keokuk1091
Worth1080
Greene1010
Montgomery965
Wayne862
Audubon821
Adair721
Decatur670
Ringgold502
Adams330
Unassigned170
Rochester
Clear
64° wxIcon
Hi: 65° Lo: 45°
Feels Like: 64°
Mason City
Clear
65° wxIcon
Hi: 67° Lo: 47°
Feels Like: 65°
Albert Lea
Clear
64° wxIcon
Hi: 66° Lo: 46°
Feels Like: 64°
Austin
Clear
64° wxIcon
Hi: 67° Lo: 46°
Feels Like: 64°
Charles City
Clear
63° wxIcon
Hi: 66° Lo: 48°
Feels Like: 63°
One Last Mild Day
KIMT Radar
KIMT Eye in the sky

Community Events