Should heart patients take the COVID-19 vaccine?

Singapore kicked off its nationwide COVID-19 vaccination programme from 30 Dec 2020 to protect Singaporeans against COVID-19, as well as to protect businesses and jobs through the progressive re-opening of Singapore. As of 28 Jan 2021, about 113,000 people have received the Pfizer-BioNTech vaccine. As we wait for our turn to receive the vaccine, here are three reasons why heart patients should go for the vaccination when offered:

Heart patients are at higher risks for COVID-19 infection
Mounting evidence has shown that while COVID-19 initially affects the airways and lungs, the inflammatory reaction that occurs later during the infection can also involve the cardiovascular system. In fact, having any heart condition such as previous heart attack, heart failure, etc. seems to represent major risk factors for an unfavourable outcome with the COVID-19 infection. This is notwithstanding that heart patients generally fall into an older age group with multiple comorbidities such as diabetes mellitus, hypertension, high cholesterol, kidney disease, etc. which render them at higher risks of developing complications with the COVID-19 infection.

The SARS-CoV-2 virus can cause direct injury to the heart in the form of inflammation of heart muscles (myocarditis), heart attack (acute myocardial infarction), heart failure, abnormal heart rhythm (arrhythmias), shock and cardiac arrest. Up to one-third of hospitalised patients have been reported to have evidence of heart muscle injury, as evident by the elevation of a blood biomarker called troponin. That is why COVID-19 patients with underlying heart conditions are 6 times as likely to be hospitalised and 12 times as likely to die, compared to those who have no such condition.

Safety of the Vaccine
There are many who think that just because the current vaccines were developed at breakneck pace, safety might have been compromised. Also, there is fear that the new mRNA technology of the early Pfizer vaccine may potentially cause long-term side effects through alteration of the cell DNA structure. The reasons why vaccines were developed so quickly are because the usual three phases of vaccine testing were being carried out concomitantly during this current pandemic. There are also many patients eligible for testing during a pandemic, thereby alleviating the problem of patient enrollment in the trials. Finally, there has been total commitment by manufacturers for rapid vaccine development and co-operation by the governing bodies to speed up review and accreditation processes.

The Pfizer vaccine is made up of a gene, which codes for a viral protein, wrapped up in a fat droplet, and administered intramuscularly. The mRNA gene makes the cell produce the viral protein to stimulate our body’s immune response to the virus but does not alter the host cell DNA structure. This is the very basic of the science behind cells and cellular function.

However, some common side effects may include soreness in the arm, headache, fatigue, chills, or fever in the early phase but most of these symptoms will resolve within a day or two. Severe allergic reactions, termed anaphylaxis, are rare and tend to occur in those with a history of allergies or allergic reactions to food, drugs, vaccines, and/or insect stings. These patients may manifest signs and symptoms of a rash, swelling of the eyes and lips, breathing difficulty and dizziness from low blood pressure. Most of these reactions occur within the first 15 minutes of injection. However, if one remained well after the mandatory 30-minute observation period, then he/she is generally safe.

Any patients with severe allergic history, however, should not receive the vaccines for now until more safety data become available.

It is also safe for heart patients to receive COVID-19 vaccination as many of them including those with medical conditions such as diabetes mellitus, hypertension, and high cholesterol, were included in the early clinical trials and were found to benefit from the vaccine. In fact, heart patients should be prioritised to get the vaccine early because of their risks of developing serious, life-threatening complications and death from COVID-19 infection.

There is no safety concern for those who are on blood thinners such as antiplatelets such as aspirin or clopidogrel. However, if you are on anticoagulants e.g. warfarin or the newer blood thinners such as rivaroxaban, dabigatran or apixaban, compression over the site of injection for 5 minutes is advised.

Efficacy of the Vaccine
The Pfizer vaccine is shown to confer up to 95% protection in individuals aged 16 years and above in the clinical trial. It is effective at preventing the onset of COVID symptoms and severe infection. Immunity starts to kick in after the first dose, but the full effect can only be reached 7 days after the second injection. By receiving the vaccine, one can not only protect themselves but also those around us, including our loved ones. Widespread vaccination of the population will help to create a protective web to reduce the number of people susceptible to the disease, and the chances of widespread transmission.

The vaccine chosen for use in Singapore has been approved by many international health regulatory authorities in the United States of America, Europe, Australia, Canada, and our very own Health Science Authority (HSA). There is no reason to believe that later vaccines are any safer or better.

In the words of A/Prof Benjamin Ong, Head Expert Committee on COVID-19 Vaccination, ‘all persons who are medically eligible to be vaccinated should do so when the vaccine is made available to them.” As more of us get vaccinated, the harder it will be for the virus to spread, and the safer we will all be as a society.

Together, we can fight COVID-19 and Cardiovascular Disease.

Article contributed by Prof Tan Huay Cheem, Chairman, Singapore Heart Foundation; Senior Consultant, Department of Cardiology and Director, National University Heart Centre, Singapore.


Prof Tan Huay Cheem receiving his COVID-19 vaccine
Photo Credit: Prof Tan Huay Cheem