Hydroxychloroquine came as a ray of hope for all of us for the treatment of covid-19, but unfortunately a recent study has punctured this silver lining.
An anti-malarial drug, Hydroxychloroquine or HCQ has been touted as a ‘wonder drug’ for the treatment of coronavirus and is now showing adverse effects. A new US study has found evidence suggesting that patients who received hydroxychloroquine for COVID-19 were at an increased risk of electrical changes to the heart and cardiac arrhythmia.
What is a cardiac arrhythmia?
Well, it is referred to a group of conditions that cause the heart to beat irregularly, too slowly, or too quickly.
The combination of hydroxychloroquine with azithromycin has been linked to even greater changes compared to hydroxychloroquine alone, according to the researchers from Beth Israel Deaconess Medical Center (BIDMC) in the US.
“While hydroxychloroquine and azithromycin are generally well-tolerated medications, increased usage in the context of covid-19 will likely increase the frequency of adverse drug events (ADEs),” said study co-author Nicholas J Mercuro from BIDMC.
This is especially concerning given that patient with underlying cardiac co-morbidities appear to be disproportionately affected by covid-19 and that the virus itself may damage the heart.
According to the study, published in the journal JAMA Cardiology, HCQ and azithromycin each can cause an electrical disturbance in the heart known as a QTc prolongation, indicated by a longer space between specific peaks on an electrocardiogram.
QTc prolongation denotes that the heart muscle is taking milliseconds longer than normal to recharge between beats. The delay can cause cardiac arrhythmias, which in turn increases the likelihood of cardiac arrest, stroke, or death.
In this single-centre, retrospective, observational study, the research team evaluated 90 adults with COVID-19 who were hospitalised at BIDMC between March 1 and April 7 and received at least one day of hydroxychloroquine.
Adverse effects of hydroxychloroquine
More than half of these patients also had high blood pressure, and more than 30% had diabetes.
Seven patients (19%) who received hydroxychloroquine alone developed prolonged QTc of 500 milliseconds or more, and three patients had a change in QTc of 60 milliseconds or more.
Of the 53 patients who also received azithromycin, 21% had prolonged QTc of 500 milliseconds or more, and 13% experienced a change in QTc of 60 milliseconds or more.
“In our study, patients who were hospitalised and receiving hydroxychloroquine for COVID-19 frequently experienced QTc prolongation and adverse drug events,” said study researcher Christina F Yen.
“One participant taking the drug combination experienced a potentially lethal tachycardia called torsades de pointes, which to our knowledge has yet to be reported elsewhere in the peer-reviewed COVID-19 literature,” Yen added.
In 2003, preliminary data suggested hydroxychloroquine may be effective against SARS-CoV-1, a fatal but hard-to-transmit respiratory virus related to the coronavirus that causes COVID-19.
More recently, a small study of patients with COVID-19 appeared to benefit from the anti-malarial drug. Subsequent research, however, has failed to confirm either finding.