Are heart palpitations a common symptom of cancer?

Heart palpitations (a feeling of fast, pounding, or irregular heartbeats) are not a typical symptom of cancer itself, but they can occur in people with cancer for several reasons. Cancer treatments, certain tumor types, and complications like blood clots can trigger arrhythmias (abnormal heart rhythms) and palpitations. ^[1] Palpitations can also be related to stress, anemia, dehydration, infections, thyroid changes, or electrolyte imbalances, which may be more common during cancer care.

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Why palpitations can happen in cancer

• Cancer treatments (cardiotoxicity): Several therapies can affect the heart’s rhythm and function, leading to palpitations or arrhythmias. Chemotherapy, targeted therapies, immunotherapy, and radiation can cause rhythm changes (arrhythmias), heart muscle injury (cardiomyopathy or myocarditis), and inflammation around the heart (pericarditis). ^[1] These rhythm changes are a recognized complication, and risk varies by the drug, dose, and the person’s heart health. ^[2]

• Specialty perspective (cardio-oncology): There is a dedicated field cardio-oncology that focuses on identifying at‑risk individuals, preventing heart side effects, and coordinating cancer and heart care. ^[3] This includes monitoring, lifestyle strategies, and cardio‑protective measures during cancer therapy. ^[4]

• Specific drug examples: Anthracyclines, fluoropyrimidines like capecitabine/5‑FU, certain tyrosine kinase inhibitors, and immune checkpoint inhibitors have been linked to arrhythmias and other cardiac events that may present with palpitations. [PM27] Immune therapies can, in rare cases, cause myocarditis or rhythm disorders that trigger palpitations. ^[5]

• Non‑treatment causes in cancer: Blood clots (such as pulmonary embolism) are more common in cancer and can cause palpitations along with breathlessness and chest discomfort. [PM22] Rare hormone‑secreting tumors (like pheochromocytoma/paraganglioma) can cause episodes of tachycardia and palpitations due to surges of catecholamines. [PM23] These causes are uncommon but important to consider when palpitations are sudden, severe, or recurrent. [PM19]

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How common is it?

• Palpitations themselves are common in the general population, but in cancer they are more often linked to treatment effects or complications rather than the cancer itself. [PM19] The likelihood depends on the specific therapy, cumulative doses (for example, anthracyclines), and personal cardiovascular risk factors. [PM25] For fluoropyrimidines (like capecitabine/5‑FU), symptomatic cardiotoxicity including chest pain and palpitations has been documented, though overall rates vary across studies. [PM27]

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Warning signs that need urgent care

• Seek immediate help if palpitations come with:

  • Chest pain, pressure, or tightness. ^[2]
  • Shortness of breath, fainting, or severe dizziness. ^[2]
  • A very fast heart rate that doesn’t settle, or new irregular heartbeat during treatment. ^[1]

  These symptoms can signal serious arrhythmias, myocarditis, coronary artery spasm, or pulmonary embolism and need prompt evaluation. ^{[2] [1]}

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Evaluation: what your care team may do

• Clinical assessment: History of treatments, timing of symptoms, vitals, and physical exam. Understanding which drug you’re on and when palpitations started helps pinpoint the cause. ^[1]
• ECG (electrocardiogram): Checks rhythm problems, conduction issues, and QT interval changes that some drugs can prolong. ^[2]
• Blood tests: Electrolytes, thyroid function, troponin/BNP (heart injury markers), and full blood count to look for anemia or infection. ^[3]
• Imaging: Echocardiogram to assess heart structure and function; CT angiography if pulmonary embolism is suspected. [PM22]
• Specialist input: Cardio‑oncology can guide risk assessment, monitoring, and treatment adjustments alongside the oncology plan. ^{[3] [4]}

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Management and prevention

• Address the trigger:

  • Adjust or pause the cancer drug if it’s causing arrhythmias, and consider dose modification per toxicity guidelines. ^[6]
  • Treat myocarditis or pericarditis promptly; immune‑related myocarditis may require steroids and immunomodulatory therapy. ^[5]
  • Manage pulmonary embolism with anticoagulation or thrombectomy when indicated and safe. [PM22]
  • Treat hormone‑secreting tumors (pheochromocytoma/paraganglioma) with alpha‑blockade and surgery when appropriate. [PM23]

• Rhythm control and supportive care:

  • Beta‑blockers or calcium‑channel blockers may help symptom control in certain arrhythmias, guided by ECG findings. [PM19]
  • Correct electrolytes (potassium, magnesium), treat anemia/dehydration, and manage thyroid issues if present. [PM19]
  • For drug‑induced QT prolongation or ventricular arrhythmias, careful monitoring and specific protocols for interruption and rechallenge may be used in select cases. ^[6] Rechallenge at lower doses has been described for certain agents under close supervision. [PM26]

• Monitoring and prevention strategies:

  • Baseline and periodic ECG/echo for higher‑risk therapies or individuals with existing heart disease. ^[3]
  • Control blood pressure and lipids, stop smoking, and maintain gentle physical activity as tolerated to lower cardiovascular risk during treatment. ^[7]
  • Report palpitations early timely communication helps prevent serious events and allows adjustments to therapy. [PM24]

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Practical tips you can try

• Track symptoms: Note when palpitations occur, duration, what you were doing, and any associated symptoms like chest pain or breathlessness. [PM19]
• Check triggers: Caffeine, alcohol, dehydration, and certain over‑the‑counter cold medicines can worsen palpitations reducing these may help. [PM19]
• Stay hydrated and rest: Gentle hydration and adequate sleep support heart rhythm stability. [PM19]
• Medication list: Keep an updated list of all medicines and supplements; share it with your care team to identify interactions that may affect the heart. ^[3]

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Key takeaways

• Palpitations aren’t usually from cancer itself, but they can happen due to treatments, blood clots, or rare hormone‑secreting tumors. ^[1] [PM22] [PM23]
• Evaluation and management mirror standard heart‑rhythm care, with extra attention to the cancer therapy involved and coordination through cardio‑oncology. ^{[3] [4]}
• Report new or worsening palpitations promptly, especially with chest pain, shortness of breath, or fainting, as these can signal urgent problems. ^{[2] [1]}

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