How does cold weather affect your heart?
With a few frosty mornings lately, and even some snow to low levels here in the South Island, it’s a good time to think about how cold weather affects people with heart conditions. A brisk walk outside in the fresh air is usually good for us, but for those with Coronary Artery Disease (CAD), the cold air and increased heart rate can immediately cause increased dyspnoea and angina, or arrhythmias. Cold weather is associated with a 20 – 25% increase in heart attack risk, particularly in the first two weeks of a cold snap.
Why is this and how does it work?
When someone feels cold, their body tries to warm up using vasoconstriction. Vasoconstriction is when blood vessels narrow to help blood stay closer to the central part of the body, keeping vital organs warm. During this process, the heart rate rises, blood pressure goes up, and the heart works harder to pump blood around the body. This can cause extra strain on those with cardiovascular conditions, particularly those with arthrosclerosis, where cold-related vessel constriction can cause angina. Cold weather can also increase the viscosity of blood, which increases the risk of clots, and may cause a stroke or heart attack.
What can we suggest for those with pre-existing heart conditions in Winter?
For patients with CAD, it is recommended that they should continue to exercise regularly to maintain cardiovascular fitness, but limit exposure to cold weather and dress warmly when going outside with layers, gloves, hat and a scarf to help prevent heat loss. Furthermore, it is recommended that those who may be affected warm up inside before going out into the cold and not exert themselves too much when exercising. Fluid intake is also encouraged (particularly water), even though the cold weather can reduce thirst perception, as it helps reduce blood viscosity.
Maintaining healthy blood pressure (BP) is also essential for protecting heart health in cold weather and preventing myocardial infarction. Target BP is typically <130/80mmHg for most adults at risk of heart disease, as this can reduce heart attack risk by up to 20%, as per guidelines from the American Heart Association.
Patients can check their BP at home or at the GP or pharmacy, which is a good idea for people who have variable blood pressure recordings and are being managed for hypertension.
At South Island Heart, we may opt to fit patients with a 24hr Ambulatory Blood Pressure Monitor (AMBP), a medical device that measures someone’s BP over a 24-hour period. An AMBP gives a more comprehensive and accurate picture of BP fluctuations, over what singular BP readings can provide. The AMBP also helps healthcare providers assess whether someone might be over or under medicated, or those affected by ‘White Coat Syndrome’ – a patient who feels particularly anxious in a medical environment resulting in an abnormally high reading when having their BP measured.
If you have concerns about the cold weather affecting your heart health, don’t hesitate to take action, and stay warm!
How can we help at South Island Heart?
At South Island Heart we are able to provide diagnostic services ECG's, Exercise Stress Tests, Echocardiograms and a Cardiologist review if required.
If you have a patient who you suspect has Takotsubo Cardiomyopathy, call us today to arrange testing with minimal wait times.