A simple electrocardiogram (ECG) can identify hospitalized COVID-19 patients at high risk of death who may need intensive treatment. That is the finding of a study presented at EHRA 2022, a scientific congress of the European Society of Cardiology (ESC).
The research showed that a prolonged QT interval on the ECG was an independent risk factor for both myocardial injury and 1-year mortality.
“An ECG is an inexpensive, noninvasive, easy-to-obtain, and widely available test that is applied to almost all hospitalized patients,” said lead author Dr. Ariel Banai of Tel Aviv Sourasky Medical Center, Israel. “Our study suggests that a simple ECG tracing performed at admission can help healthcare professionals triage patients with COVID-19 and identify those who need intensive care.”
The QT interval refers to the electrical signal from the moment the heart’s ventricles contract until they finish relaxing and is measured in milliseconds. Patients with a prolonged QT interval are at increased risk of life-threatening arrhythmias (heart rhythm disorders) and cardiac arrest.
This study examined the association between QT prolongation and long-term mortality in patients hospitalized with COVID-19. It also evaluated the relationship between QT prolongation and myocardial injury, a condition in which heart cells die.
A total of 335 consecutive patients hospitalized with COVID-19 were prospectively studied. All patients had an ECG on admission. Patients were considered to have myocardial injury if they showed reduced function on an echocardiogram, which is an ultrasound of the heart, and/or had troponin in their bloodstream. Troponin is a protein found only in heart cells . When the heart is damaged, for example in a myocardial injury, troponin is released into the bloodstream.
Patients were divided into two groups according to the duration of the QT interval: 109 patients (32.5%) had a prolonged QT interval and 226 patients (67.5%) had a normal QT interval. Compared with those with a normal QT interval, patients with a prolonged QT interval were older (average 70 years vs. 63 years), more frequently had coexisting conditions such as hypertension, diabetes, and congestive heart failure, and more frequently had heart failure. serious heart. as opposed to mild) COVID-19.
78 patients (71.6%) with QT prolongation had myocardial damage compared to 110 (48.7%) with a normal QT interval. Prolonged QT interval was associated with a two-fold increased risk of myocardial injury after adjusting for age, coexisting conditions, and COVID-19 severity.
Dr Banai said: "Interestingly, among patients with myocardial injury, half had no troponin in their blood , suggesting that blood tests alone may miss a considerable number of patients with this heart problem. ".
At one year, 41% of patients in the prolonged QT group had died compared with 17% in the normal QT group. QT prolongation was associated with a 1.85-fold increased risk of dying within one year after adjusting for age, coexisting conditions, and COVID-19 severity.
When patients were divided into four groups based on the presence of myocardial injury (yes/no) and QT prolongation (yes/no), those with both conditions were 6.6 times more likely to have one-year mortality compared to those with patients without QT prolongation and without myocardial injury.
Dr. Banai said: “In our study, one-third of patients hospitalized with COVID-19 had a prolonged QT interval. These patients were generally older and sicker, but even after adjusting for these factors, prolonged QT interval was independently associated with worse survival. “Further studies are needed to confirm our observations, but the results indicate that ECG assessment could play a role in risk stratification of patients admitted with COVID-19 infection.”
Presenter: Ariel Banai (Tel Aviv Sourasky Medical Center - Tel Aviv, Israel)
