Heart palpitations are sensations of a heart beating too fast, too hard, or irregularly, often felt as fluttering, pounding, or racing. Breast cancer involves uncontrolled growth of abnormal cells in breast tissue. This article explores the relationship between breast cancer and heart palpitations, examining direct causation or other connections.
Absence of a Direct Causal Link
Breast cancer itself does not directly cause heart palpitations. Tumor growth and spread within the breast typically do not directly impact the heart’s electrical system or pumping function. While both breast cancer and heart conditions are significant health concerns, one does not inherently lead to the direct manifestation of the other as a symptom.
Treatment-Related Causes of Palpitations
Many connections between breast cancer and heart palpitations stem from treatments. Certain chemotherapy drugs have cardiotoxic effects, meaning they can damage the heart muscle. Anthracyclines, like doxorubicin, can weaken the heart muscle, leading to cardiomyopathy, which may result in arrhythmias or palpitations. Taxanes, including paclitaxel and docetaxel, have also been associated with heart rhythm disturbances.
Radiation therapy to the chest, especially for left-sided breast cancer, can affect heart tissue over time. Radiation exposure may contribute to conditions like pericarditis (inflammation of the sac surrounding the heart) or damage to heart valves and coronary arteries. These effects can manifest as heart rhythm irregularities, including palpitations. Risk relates to radiation dose and field, with modern techniques minimizing cardiac exposure.
Hormone therapies, which block hormones fueling certain breast cancers, can have cardiovascular implications. Tamoxifen has been linked to an increased risk of blood clots, which may contribute to cardiac events perceived as palpitations. Aromatase inhibitors (anastrozole, letrozole, exemestane) can alter lipid profiles and are associated with increased risk for heart failure, cardiovascular mortality, and arrhythmias, including atrial fibrillation. These changes can indirectly contribute to palpitations.
Targeted therapies, which attack specific cancer cells, may also have cardiac side effects. Trastuzumab, used for HER2-positive breast cancer, can decrease heart pumping function, leading to symptoms like heart failure, which may include palpitations. These effects are often reversible with early detection and management, highlighting the importance of monitoring heart health throughout treatment.
Other Indirect Connections
Beyond treatment, other indirect factors can link breast cancer and heart palpitations. The psychological burden of a cancer diagnosis, including stress and anxiety, can contribute to palpitations. Stress hormones influence heart rhythm, making palpitations a common physiological response to heightened anxiety.
Pre-existing cardiovascular conditions can be exacerbated by the stress of a cancer diagnosis and treatment. Conditions like hypertension, coronary artery disease, or arrhythmias can worsen under physical and emotional strain. Breast cancer and certain cardiovascular conditions also share common risk factors, such as age or lifestyle.
In rare instances, breast cancer can metastasize to the heart. Cancer cells infiltrating the heart muscle or pericardium could disrupt its electrical activity or mechanical function, leading to rhythm disturbances. This is an infrequent occurrence compared to other metastasis sites. Even more rarely, paraneoplastic syndromes, immune responses triggered by cancer, could impact the heart, though this is exceptionally rare with breast cancer and palpitations.
When to Consult a Healthcare Provider
Anyone experiencing heart palpitations, especially with a history of breast cancer or its treatment, should consult a healthcare provider. Seek medical attention if palpitations are accompanied by other concerning symptoms, such as chest pain, shortness of breath, dizziness, lightheadedness, or fainting. These symptoms could indicate a serious underlying cardiac issue requiring prompt evaluation.
Open communication with the oncology team and primary care physician about new or worsening symptoms is important. A medical professional can diagnose the cause of palpitations through medical history, physical examination, and diagnostic tests like an electrocardiogram or echocardiogram. Early evaluation allows for appropriate management of potential cardiac issues.