What to Do About Heart Palpitations Caused by Hypothyroidism

Experiencing heart palpitations due to hypothyroidism can be both unsettling and concerning. While an underactive thyroid is typically associated with a slow metabolism and fatigue, it can also lead to cardiovascular symptoms like heart palpitations. The connection between thyroid function and heart health is well-documented, and managing these symptoms effectively requires understanding the root causes. Below, we explore the various reasons behind heart palpitations in hypothyroid patients and provide practical solutions for relief.

Understanding the Link Between Hypothyroidism and Heart Palpitations

Hypothyroidism slows down the body's metabolic processes, which can directly affect heart function. When thyroid hormone levels are too low, the heart muscle may not receive adequate oxygen, potentially leading to ischemia or even pericardial effusion—a buildup of fluid around the heart. This condition, sometimes referred to as "myxedema heart disease," can result in bradycardia (slow heart rate), but paradoxically, patients often report feelings of heart fluttering or palpitations due to reduced cardiac efficiency.

In such cases, the primary treatment involves restoring normal thyroid function using synthetic thyroid hormone replacement, such as levothyroxine (commonly known as Synthroid or Levoxyl). Once thyroid levels stabilize through consistent medication, many cardiovascular symptoms—including palpitations—tend to resolve naturally.

Managing Medication Sensitivity in Older Adults

Starting Low and Going Slow

Not everyone responds to thyroid medication in the same way. Elderly patients, especially those with pre-existing heart conditions, may experience intolerance when beginning levothyroxine therapy. Even though the goal is to correct hormone deficiency, introducing the medication too quickly can stress the cardiovascular system, triggering palpitations or arrhythmias.

To minimize risks, doctors often recommend starting with a low dose and gradually increasing it based on regular blood tests and clinical response. This cautious approach allows the heart to adapt smoothly to rising metabolic demands, reducing the likelihood of adverse effects.

When Too Much Medication Triggers Hyperthyroid Symptoms

An overdose of levothyroxine can inadvertently push a patient into a hyperthyroid state—where the body experiences excess thyroid hormones. This overcorrection can cause symptoms such as rapid heartbeat (tachycardia), anxiety, sweating, and pronounced heart palpitations. It's crucial to recognize that both too little and too much thyroid hormone can disrupt heart rhythm.

If you're experiencing increased heart rate or jitteriness after starting or adjusting your medication, consult your healthcare provider immediately. Blood tests measuring TSH, free T4, and sometimes free T3 will help determine whether your dosage needs to be recalibrated.

Diagnostic Steps for Accurate Treatment

To effectively manage heart palpitations related to thyroid disorders, proper diagnosis is essential. Your doctor may recommend several tests to evaluate both thyroid and heart function:

• Thyroid Function Tests: Including TSH, free T4, and free T3 levels to assess hormonal balance.
• Electrocardiogram (ECG/EKG): To detect any irregularities in heart rhythm.
• Echocardiogram: An ultrasound of the heart to check for structural issues like pericardial effusion or reduced pumping efficiency.

These diagnostic tools help differentiate between palpitations caused by untreated hypothyroidism, medication side effects, or independent cardiac conditions.

Conclusion: A Personalized Approach Is Key

Heart palpitations in individuals with hypothyroidism are common but manageable. Whether stemming from low thyroid activity, medication sensitivity, or overtreatment, identifying the exact cause is vital for effective care. With proper monitoring, gradual medication adjustment, and ongoing communication with your healthcare team, most people can achieve both optimal thyroid function and improved heart health.

Remember, consistency in taking medication, attending follow-up appointments, and reporting new or worsening symptoms are all part of successful long-term management.