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Covid-19 Impacts the Heart and Blood Vessels (The Cardiovascular System).

Covid-19 Damages the Heart and Blood Vessels

Covid infection, even when mild, substantially increases risk of cardiovascular illness up to at least 1 year later

(Xie et al., 2022 doi: 10.1038/s41591-022-01689-3)

• Capillary density (how many small blood vessels are present) is reduced by 41% in sufferers of Long Covid 18 months after Covid infection

(Osiaevi et al., 2022 doi: 10.1007/s10456-022-09850-9)

• Acute Covid infection results in 6x increase in cardiovascular diagnosis; 11x increase in pulmonary embolism (blood clot in lung); 6x increase in atrial arrhythmias (abnormal heartbeat); 5x increase in venous thromboses (blood clot in vein).

(Rezel-Potts et al., 2022 doi: 10.1371/journal.pmed.1004052)

• A spike protein found on Covid-19 virus particles uses the body’s immune response to damage and inflame heart muscle cells.


• People with Covid exhibited increased risks and 12-month burdens of incident cardiovascular diseases, including cerebrovascular (blood vessels in the brain) disorders, dysrhythmias (abnormal heart rhythm), inflammatory heart disease, ischemic heart disease, heart failure, thromboembolic (blood clotting) disease and other cardiac disorders. Risk were evident even in those without prior cardiovascular disease.

(Xie et al., 2022 doi: 10.1038/s41591-022-01689-3)

• Risk of stroke more than doubles even with mild or asymptomatic Covid infection. Median time of stroke is 2 months after Covid diagnosis.

(Tu et al., 2021 doi: 10.1001/jamanetworkopen.2021.7498)

• Acute Covid infection increases heart attack risk by 3-8x and stroke risk by 3-6x

(Katsoularis et al., 2021 doi: 10.1016/S0140-6736(21)00896-5)

• Long Covid is associated with presence of microclots throughout the body.

(Pretorius et al., 2021 doi: 10.1186/s12933-021-01359-7)

• Long Covid patients may face an increased risk of abnormal blood clotting.


• A study of Swiss Army personnel, with an average age of 21, found that those infected with Covid showed higher BMI, dyslipidaemia, and lower physical endurance 180 days after infection, placing them at higher risk of developing metabolic disorders and cardiovascular complications.

(Deuel et al., 2022 doi: 10.1016/S1473-3099(22)00449-2)

• In healthy individuals with mild Covid infection, 73% and 57% reported cardiac symptoms at a median of 109 and 329 days, respectively. Symptoms included exertional dyspnoea (shortness of breath with physical activity), palpitations, atypical chest pain and fainting and correlated with cardiac inflammation on imaging. Findings did not differ between vaccinated and unvaccinated groups and the whole group.

(Puntmann et al., 2022 doi: 10.1038/s41591-022-02000-0)

• Doctors report that young and middle-aged people, with mild symptoms of Covid infection, are dying from strokes.


• A study of 80 Long Covid patients showed presence of microclots and platelet pathologies in 100% of patients. These block capillaries, starving tissues of oxygen.

(Pretorius et al., 2022 *preprint doi: 10.21203/

• Multiple geographic regions of high Covid spread have reported increased out-of-hospital cardiac arrest and sudden death, such as Lombardy in Italy which experienced a 77% rise.

(Topol, 2020, doi: 10.1126/science.abe2813)

• A study of 100 patients recovered from Covid showed through cardiovascular MRI that 78% had cardiac involvement and 60% had ongoing myocardial (heart muscle) inflammation. Cardiac findings were independent of pre-existing conditions and infection severity.

(Puntmann et al., 2020 doi: 10.1001/jamacardio.2020.3557)

• In 901 patients without pre-existing cardiac disease, Covid infection resulted in abnormal echocardiograms (heart scan using ultrasound) in 46% and severe disease in 13%.

(Dweck et al., 2020 doi: 10.1093/ehjci/jeaa178)

• In 26 healthy, competitive college athletes previously infected with Covid, cardiovascular MRI showed 8 (30.8%) had previous myocardial injury and 4 (15%) had myocarditis (inflammation of the heart), which is often asymptomatic but can lead to sudden death.

(Rajpal et al., 2020 doi: 10.1001/jamacardio.2020.4916)

• Increases in proteins that promote blood clotting and persistent endothelial cell (blood vessel lining) activation is seen in Long Covid, caused by immune dysfunction

(Fogarty et al., 2022, doi: 10.1111/jth.15830)

• Patients following Covid infection are more likely to have a reduced Myocardial Flow Reserve (potential increase in blood flow to heart upon increased activity). This indicates endothelial (blood vessel lining) injury.

(Ahmed et al., 2022 doi: 10.1016/j.jcmg.2022.07.006)

• Strokes in Covid positive patients occur at a significantly younger age; in patients lacking cerebrovascular risk factors and have higher morbidity (reduced quality of life) and mortality (death rate) than strokes in those uninfected.

(Pascal et al., 2022, doi: 10.1227/neu.0000000000001902)

• Up to a quarter of hospitalised Covid patients show abnormal blood clotting one year after discharge.



• Researchers find that after 30 days post-Covid infection, risk of lung blood clots (pulmonary embolism) is increased 33x, risk of vein blood clots (venous thromboembolism) is increased 5x and risk of bleeding is doubled.

(Katsoularis et al., 2022 doi: 10.1136/bmj-2021-069590)

• Autopsy findings show that Covid-19 infection causes endotheliitis (inflammation of the inner lining of blood vessels) in organs throughout the body.

(Varga et al., 2020 doi: 10.1016/S0140-6736(20)30937-5)

• Risk of blood clots remains elevated for at least 49 weeks following Covid-19 infection in unvaccinated people. Data was taken from the medical records of 48 million UK people during 2020 to determine this risk.

(Knight et al., 2022 doi: 10.1161/CIRCULATIONAHA.122.060785)

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