The Covid-19 scourge caused by the SARS-CoV-2 virus is widely recognised for its effects on the respiratory system.
However, in addition to lung damage, the virus also had major effects on the cardiovascular system, similar to previous coronavirus outbreaks such as Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS).
Experts say while Covid-19 primarily targets the lungs, it can also lead to serious heart complications, including blood clots, inflammation, irregular heart rhythms, and heart failure.
Lung damage caused by Covid-19 can prevent oxygen from reaching the heart muscle, leading to tissue damage and impairing the heart’s ability to deliver oxygen to the rest of the body.
“Covid-19 wasn’t just a respiratory disease - it affected multiple organs, with the heart being one of the most affected,” said Dr Etienne Amendezo, a consultant interventional cardiologist at the Aga Khan University Hospital.
Dr Daniel Nduiga, a cardiologist at the Heart Rhythm Medical Centre, said during the pandemic, about two in 10 severe Covid-19 patients experienced heart problems.
These complications ranged from heart attacks caused by excessive clotting and inflammation to type 2 myocardial infarction - a condition in which factors other than coronary artery disease (CAD) create a critical imbalance between oxygen supply and demand.
Dangerous arrhythmias-where the heart beats too fast, too slow or irregularly, were also common.
“Unlike traditional heart attacks, which are caused by cholesterol build-up in the arteries, these were primarily caused by excessive clotting and inflammation,” Dr Nduiga explained.
“We had to adjust our approach, relying more on blood thinners and drugs rather than typical interventions such as stents.”
Cases of arrhythmias were of particular concern, as patients’ heart rates could rise dangerously, increasing their risk of heart attacks. In addition, Covid-19 caused pulmonary hypertension, which put immense pressure on the right side of the heart, making recovery even more difficult.
According to Dr Etienne, Covid-19 caused inflammation in the heart muscle, leading to myocarditis.
“Many patients developed abnormal heart rhythms, with some experiencing dangerously fast heartbeats that increased their risk of sudden cardiac arrest. In severe cases, widespread clotting led to sudden heart failure,” he said. “We lost many critically ill patients to cardiovascular complications, and this was not limited to Kenya; it was a global phenomenon.”
Notably, some patients with no history of heart disease developed severe cardiovascular complications. “We observed patients with no history of heart disease who suddenly developed severe heart problems,” Dr Etienne said.
The elderly, those with diabetes, and those with hypertension were among the most vulnerable, although there was no significant difference in risk between men and women.
In the post-pandemic period, heart attack rates have not necessarily increased because of Covid-19 itself. Instead, pre-existing risk factors such as obesity, high blood sugar, high blood pressure, and smoking remain the main drivers of heart disease.
“We no longer see a direct link between Covid-19 and increased heart attack rates,” said Dr Nduiga.
“However, some patients with long Covid continue to experience problems such as high blood pressure, irregular heartbeat and stroke.”
While Covid-19 has raised awareness of cardiovascular health, the biggest challenge remains lifestyle-related heart disease.
“The main causes of heart attacks are still smoking, obesity, high blood pressure, and diabetes,” said Dr Etienne. “However, we continue to see some patients suffering from the long-term inflammatory effects of previous Covid-19 infections, which can exacerbate these conditions.”
Since 2013, there has been a steady increase in the number of heart attacks, largely due to lifestyle changes. Poor diet, smoking, and lack of exercise have become more common. “We have seen more young people developing heart disease because of their lifestyle choices,” said Dr Nduiga.
In Kenya, adoption of westerners’ habits has led to higher rates of hypertension and diabetes, both of which contribute to heart disease.
Increased life expectancy also means more people are reaching the age when these conditions become prevalent.
During the pandemic, heart attack cases initially fell as people avoided hospitals for fear of contracting Covid-19.
“Many heart patients stayed at home and delayed treatment. By the time they finally sought help, their condition had worsened. Some had stopped taking their medications, while others ignored symptoms until they became life-threatening,” Dr Etienne said.
The pandemic also changed the way cardiovascular cases were managed, forcing doctors to adapt to new challenges.
“Unlike typical heart attacks, many Covid-19-related cardiac complications developed while patients were already in hospital,” said Dr Nduiga.
“We had patients whose heart rate suddenly became dangerously fast and others whose blood pressure dropped to critical levels. Many were already in intensive care when their condition deteriorated. As the world moves forward, cardiovascular disease remains a major concern."
“Covid-19 brought heart health into focus, but the biggest battle is still lifestyle-related heart disease,” said Dr Etienne.
“We need to continue to encourage people to make healthier choices, schedule regular check-ups, and manage their risk factors early.”
Dr Nduiga emphasised that “Covid-19 was a wake-up call, but preventing heart attacks still comes down to the basics - diet, exercise, and proactive healthcare”.
Covid-19 was first identified in December 2019 in Wuhan, China. The World Health Organization (WHO) declared it a global pandemic on March 11, 2020 due to the rapid spread of the virus around the world, causing health, economic, and social challenges.
Kenya confirmed its first case of Covid-19 on March 13, 2020. The government responded with measures such as expanded testing, improved case management, movement restrictions to slow transmission, and economic incentives to support businesses.
By May 2022, more than 10 million doses of five types of Covid-19 vaccine had been administered, with 4.2 million people fully vaccinated and 5.9 million partially vaccinated.
The pandemic brought to the fore the importance of preparedness and response to public health emergencies. In April 2023, Kenya partnered with WHO to establish a Regional Emergency Hub in Nairobi to strengthen the region’s capacity to respond to future health crises.
On May 5, 2023, the WHO declared that the pandemic no longer constituted a public health emergency of international concern (PHEIC), citing declining mortality rates, reduced hospitalisations, and increased community immunity. However, the WHO does not officially declare the beginning or end of pandemics. Although the emergency phase has ended, Covid-19 continues to circulate worldwide, requiring continued vigilance.
In Kenya, the Ministry of Health has not made a formal declaration of the end of the pandemic but continues to monitor the situation.
