Initially recognized as a respiratory system disease, COVID-19 has been found to interact with and affect the cardiovascular system, resulting in a slew of cardiac ailments ranging from myocardial damage to cardiac and endothelial dysfunction (1). Cardiac damage has been noted even without clinical features of respiratory disease. Further, some cardiac symptoms have been known to persist in certain patients, greatly complicating their recovery. Recently however, a treatment has emerged in ivabradine for persistent cardiac COVID-19 symptoms.
At the start of the COVID-19 pandemic, a surprising volume of hospitalized patients were found to have elevated levels of cardiac troponin, a marker of myocardial injury. Soon thereafter, echocardiograms confirmed cardiac functional abnormalities in many patients (2). A recent meta-analysis of studies on long COVID-19 found that up to 11% of COVID-19 patients report experiencing palpitations or an increased heart rate (3). These may include, but are not limited to, myocardial infarction, coronary artery disease, arrhythmias, and conduction system disease. While the underlying causes remain unclear, one study based on an online survey of over 2,000 adults with long COVID interestingly found that up to two thirds of patients have symptoms suggestive of an impaired autonomic nervous system, which controls “automatic” functions of the body, including blood pressure, digestion, body temperature – and heart rate.
COVID-19-related cardiac symptoms are similar to the broader condition known as postural orthostatic tachycardia syndrome (POTS). Even prior to the COVID-19 pandemic, POTS was known to affect more than 24 million Americans, especially in patients recovering from influenza or another viral infection. POTS can impact employment and education, similar to severe cardiac ailments, and it is important to treat quickly and effectively.
While beta blockers and calcium channel blockers may be administered, these can lower blood pressure and may make patients feel worse. Ivabradine (Procoralan), meanwhile, is a drug that selectively reduces heart rate via ion channel current inhibition in the heart’s sinoatrial node without inducing a negative effect on inotropy. Confirming results found prior to the COVID-19 pandemic, a 2021 randomized controlled clinical trial involving 22 people demonstrated that ivabradine was effective at lowering the heart rate in POTS patients, which suggests that it may be applicable to COVID-19 patients as well (4). While its precise mechanism of action remains unknown, ivabradine is now commonly prescribed, along with exercises, to hundreds of POTS patients, including many with long COVID-19 (5).
Besides selective heart rate reduction, ivabradine has been found to result in a number of addition beneficial effects. These include anti-inflammatory, anti-atherosclerotic, anti-oxidant and antiproliferative effects, in addition to attenuating endothelial dysfunction and neurohumoral activation (6).
Ivabradine has emerged as a promising drug in the treatment of persistent cardiac COVID-19 symptoms, with minimal negative side effects. Additional research will be required to elucidate its precise mechanism of action and improve its administration protocol.
- Basu-Ray I, Soos MP. Cardiac Manifestations Of Coronavirus (COVID-19). StatPearls. 2020.
- Abbasi J. Researchers Investigate What COVID-19 Does to the Heart. JAMA – J Am Med Assoc. 2021;
- Lopez-Leon S, Wegman-Ostrosky T, Perelman C, Sepulveda R, Rebolledo PA, Cuapio A, et al. More than 50 long-term effects of COVID-19: a systematic review and meta-analysis. Sci Rep. 2021; doi: 10.1101/2021.01.27.21250617.
- Taub PR, Zadourian A, Lo HC, Ormiston CK, Golshan S, Hsu JC. Randomized Trial of Ivabradine in Patients With Hyperadrenergic Postural Orthostatic Tachycardia Syndrome. J Am Coll Cardiol. 2021; doi: 10.1016/j.jacc.2020.12.029.
- Heart-Failure Drug Used to Treat Long Covid Symptoms – Bloomberg [Internet]. [cited 2022 Jul 25]. Available from: https://www.bloomberg.com/news/articles/2022-05-25/heart-failure-drug-used-to-treat-long-covid-symptoms
- Baka T, Repova K, Luptak I, Simko F. Ivabradine in the management of COVID-19-related cardiovascular complications: A perspective. Curr Pharm Des. 2022; doi: 10.2174/1381612828666220328114236.