Medical Oncologist
Heart monitoring
Heart Function Drop — What an Ejection Fraction Drop Means on Targeted Therapy
Some targeted cancer drugs can reduce the amount of blood the heart pumps with each beat. This is measured as ejection fraction, and it is why your team monitors your heart during treatment. Caught on a scan before symptoms appear, most cases can be managed. Certain symptoms need urgent care today.
Medically reviewed by Dr. Bharati Devi Gorantla, Medical Oncologist, MBBS · MD · DM (Adyar, Chennai) · ECMO · MRCP SCE (UK) · Last reviewed August 2026
- Detected on echocardiogram — Your team schedules heart scans during targeted therapy precisely to catch any change before it causes symptoms.
- Often reversible — For many patients on HER2-targeted drugs, heart function recovers once treatment is paused and the heart is supported.
- Some symptoms need emergency care — Chest pain, breathlessness at rest, and leg swelling that appears suddenly are not symptoms to wait on.
- Do not stop treatment alone — If you are worried about your heart, call your team today — do not simply stop your medication without telling them.
17+
Cancer Specialists
on Panel
on Panel
96.9%
Breast Cancer
Survival Rate*
Survival Rate*
15,000+
Patients
Treated
Treated
4.8★
Google Rating
(800+ reviews)
(800+ reviews)
An ejection fraction drop means the heart is pumping less efficiently than it was. It happens with some targeted therapies and your team monitors for it with regular scans. Caught early, many cases are reversible. If you have chest pain, breathlessness at rest, or sudden leg swelling, go to hospital now — do not wait for your next appointment.
If a symptom below applies to you, do not wait for a callback. Call 1800-202-8726 or go to your nearest emergency department.
Is an ejection fraction drop always dangerous?
Not always — but it is always something your team needs to know about. An EF drop that shows up on a scheduled monitoring scan, before you have any symptoms, is very different from one discovered because you are breathless at rest.
For patients on HER2-targeted therapy, EF drops are often reversible. ASCO and ACC cardio-oncology guidance recognises that pausing treatment and supporting the heart with medication can allow function to recover in a proportion of patients — sometimes enough to restart therapy.
The risk is when the drop is missed, or when symptoms appear and are not reported. The monitoring scans are not optional — they exist to catch a change at the point it is most manageable.
Being told your EF has dropped is not the same as being told your heart is permanently damaged. It is a finding that changes how your treatment is managed, not necessarily a reason it has to stop.
Meet the Specialists
17+ senior cancer specialists. One panel for your case.
Trained at AIIMS, Tata Memorial, and leading international centres. Combined 150+ years of experience. Every complex case is reviewed by 3+ of them — together.
Medical Oncologist
Dr. C. Raghavendra Reddy
MBBS(Gold Medal), DNB(General Medicine), DM(Medical Oncology)(Gold Medal)
Medical Oncologist
Dr. Bharati Devi Gorantla
MBBS, MD(General Medicine), DM(Medical Oncology)(Adyar,Chennai), ECMO, MRCP SCE(UK)
Medical Oncologist
Dr. Owais Mohammed
MBBS, MD (General Medicine), DrNB (Medical Oncology), ECMO, MRCP SCE (Medical Oncology) (UK)
Medical Oncologist
Medical Oncologist
Surgical Oncologist
Dr. Muralidhar Muddusetty
MBBS (AIIMS), MS (Surgery) (AIIMS), DNB (Surgical Oncology), MRCS (Edinburgh)
Surgical Oncologist
Surgical Oncologist
Surgical Oncologist
Dr. Vinay Mamidala
MBBS, MS(General Surgery), M.Ch(Surgical Oncology), FMAS, FARIS(Ongoing)
Surgical Oncologist
Radiation Oncologist
Radiation Oncologist
Radiation Oncologist
Hematologist
Interventional Radiologist
Dr. Mohammed Imran
Surgical Oncologist
Dr. Vajja Sandeep Kumar
MBBS, MS (General Surgery), DrNB (Surgical Oncology), FALS Oncology
Surgical Oncologist
Want a specific doctor for your case? Mention them when booking.
Book Free ConsultationBook an appointment with our specialist
Share your name and number — we'll call you back within 30 minutes to schedule your consultation.
Not sure whether this counts as an emergency?
Call the helpline. It is always better to check than to wait.
What to track between your heart monitoring scans
- Notice whether you get more breathless than usual climbing stairs or walking a short distance.
- Check your feet and ankles each evening for any new swelling.
- Note whether lying flat feels harder than it used to — needing extra pillows to sleep comfortably is a symptom worth reporting.
- Pay attention to any new feeling of your heart racing, fluttering or pounding, even briefly.
- Write down the date any new symptom starts — your team will ask.
- Weigh yourself at the same time each morning if your team has asked you to — a rapid gain can be a sign of fluid building up.
How do you tell manageable symptoms from ones that need urgent action?
| Symptom | Can wait for next appointment | Call your team today | Go to hospital now |
|---|---|---|---|
| Breathlessness | Only on significant exertion, no change from your usual | Getting breathless on less effort than before — stairs that used to be fine | Breathless at rest, or waking from sleep feeling unable to breathe |
| Leg or ankle swelling | Mild puffiness at day's end that is gone by morning | Persistent swelling through the day, not gone overnight | Sudden severe swelling in both legs, especially with breathlessness |
| Heartbeat | Normal rhythm, no change | Occasional brief palpitations — heart fluttering or skipping | Racing heartbeat with dizziness, faintness or chest discomfort |
| Chest symptoms | None | Vague mild discomfort that comes and goes — mention at your next visit | Any chest pain, tightness or pressure — go now |
| Typically starts | — | Weeks to months after starting targeted therapy, but can occur at any point | Can occur at any time — do not wait |
Questions about heart monitoring during targeted therapy
Will treatment have to stop permanently if my EF has dropped?
Not necessarily. Whether treatment is paused, adjusted or stopped depends on how much the EF has changed, whether you have symptoms, and how well your heart responds to management. ASCO and ACC cardio-oncology guidance notes that in a proportion of patients on targeted therapy, function recovers enough to restart. Your oncologist and, in many cases, a cardiologist will make this decision together based on your specific results. Stopping permanently is one option among several, not the automatic outcome of a drop.
What does ejection fraction actually measure?
Ejection fraction is the proportion of blood in the heart's main pumping chamber that is pushed out with each beat. When EF drops, less blood reaches the body's circulation with each beat, and the heart has to work harder to compensate. An echocardiogram measures this using sound waves — it does not use radiation and takes less than an hour. This is the scan your team will repeat during and after any period of concern.
Can anything protect my heart during targeted therapy?
Your team may consider heart-protective medication alongside your cancer treatment, and this is worth discussing with your oncologist before problems develop. Keeping blood pressure well controlled matters, as does managing other cardiac risk factors such as diabetes and cholesterol if they apply to you. Do not start any new supplement, herbal preparation or over-the-counter medicine without telling your oncology team first — some interact with targeted drugs in ways that are not obvious. Tell your team about everything you are taking.
What does a treatment hold mean for my cancer?
A treatment hold means your targeted therapy is paused while your heart is monitored and, if needed, supported with medication. It does not mean the treatment has failed or that the cancer is being left untreated — your team will explain how the cancer will be watched during the pause. For many patients the hold is temporary, and the question of restarting is reviewed once the heart has had time to recover. Ask directly: what does my heart need to show before restarting is considered, and when will that decision be made?
Should I avoid exercise if my EF has dropped?
Do not make that decision alone. For a significant or symptomatic EF drop, your team will advise you to rest and avoid exertion until the situation is fully assessed. For a mild drop without symptoms, the answer is not necessarily to stop all activity — but the right level is something to agree with your cardiologist, not to judge yourself. Do not push through breathlessness during activity, and do not use exercise to test whether your heart is coping. Let your team guide you on this specifically.
Explore 108 more Side Effects, Emergencies & Daily Living topics
Side Effects - Symptom-Specific Deep Dives
- Abdominal Pain on Targeted Therapy: When to Worry
- Acne-Like Rash on EGFR Inhibitors: Why It Happens and How to Treat It
- Anaemia and Low Haemoglobin During Targeted Therapy
- Blood Clots and Stroke Risk on Targeted Therapy
- Blurred Vision and Eye Problems on Cancer Drugs
- Brain Fog and Memory Problems During Treatment
- Breathlessness and Cough on Targeted Therapy: Ruling Out ILD
- Constipation During Targeted Therapy
- Diarrhoea on Targeted Therapy: How to Control It at Home
- Dry Eyes and Light Sensitivity During Treatment
- Extreme Fatigue on Targeted Therapy: Causes and What Helps
- Extremely Dry, Cracking Skin on Cancer Tablets
- Fever During Targeted Therapy: Home Care vs Emergency
- Hair Thinning, Curling and Colour Change on Targeted Therapy
- Hand-Foot Skin Reaction: Prevention and Relief
- Headaches and Dizziness on Targeted Therapy
- Heart Function Drop (Low Ejection Fraction) on Targeted Therapy
- High Blood Pressure Caused by Cancer Drugs
- High Blood Sugar on PI3K and mTOR Inhibitors
- Infusion Reactions: What Happens and How They're Managed
- Interstitial Lung Disease (ILD): The Side Effect You Must Not Ignore
- Itching That Won't Stop on Targeted Therapy
- Kidney Function Changes on Targeted Therapy
- Loss of Appetite and Weight Loss During Targeted Therapy
- Low Magnesium and Electrolyte Problems on Anti-EGFR Antibodies
- Low Platelets on PARP Inhibitors and TKIs
- Low White Cells and Infection Risk on Targeted Therapy
- Mouth Ulcers and Mucositis: Practical Relief
- Muscle Cramps and Joint Pain on Cancer Drugs
- Nausea and Vomiting on Oral Cancer Drugs
- Osteonecrosis of the Jaw: Prevention During Bone-Targeted Treatment
- Paronychia and Nail Changes on Targeted Therapy
- Peripheral Neuropathy: Tingling and Numbness in Hands and Feet
- Protein in Urine (Proteinuria) During Treatment
- QT Prolongation: What It Means on Your ECG Report
- Raised Liver Enzymes (SGPT/SGOT) on Targeted Therapy
- Secondary Cancers After Long-Term PARP Inhibitor Use
- Severe Rash With Fever or Blistering: A Medical Emergency
- Skin Darkening, Depigmentation and Pigment Changes
- Slow Heart Rate and Dizziness on Certain TKIs
- Sun Sensitivity and Photosensitivity on Cancer Drugs
- Swallowing Difficulty and Reflux on Cancer Tablets
- Swelling of Face, Legs and Around the Eyes
- Taste Changes and Metallic Mouth on Cancer Drugs
- Tumour Lysis Syndrome: A Rare but Serious Early Complication
- Underactive Thyroid (Hypothyroidism) Caused by Cancer Drugs
- Unusual Bleeding or Bruising on Cancer Drugs
- Voice Changes and Hoarseness on Targeted Therapy
- Weight Gain During Long-Term Targeted Therapy
- When Diarrhoea Becomes an Emergency: The Rule You Must Know
- Wound Healing Problems on Antiangiogenic Drugs
Daily Living & Adherence
- Can I Drink Alcohol on Targeted Therapy?
- Can I Drive While on Targeted Therapy?
- Can I Fast for Religious Reasons During Targeted Therapy?
- Can I Have Dental Treatment While on Targeted Therapy?
- Exercise During Targeted Therapy: How Much Is Safe?
- Haircuts, Waxing, Facials and Tattoos During Treatment
- How Should Family Members Handle Your Cancer Tablets Safely?
- I Accidentally Took a Double Dose: How Serious Is It?
- I Missed a Dose of My Targeted Therapy: What Should I Do?
- I Vomited Right After Taking My Tablet: Do I Repeat the Dose?
- Managing a Household Routine Around Your Dosing Schedule
- Pets, Gardening and Infection Precautions
- Running Out of Medicine: What to Do About Refills and Shortages
- Safe Disposal of Unused Cancer Medicines
- Sex and Intimacy While on Targeted Therapy: Safety Questions
- Sleep Problems on Targeted Therapy and What Actually Helps
- Smoking and Targeted Therapy: How It Changes Your Drug Levels
- Travelling With Cancer Tablets: Flights, Security and Storage
Emergency & Red-Flag Triage
- Chest Pain or Palpitations During Cancer Treatment
- Emergency Contact Card: What to Keep in Your Wallet
- Fever Above 100.4F on Cancer Treatment: The 1-Hour Rule
- Heavy Bleeding, Blood in Vomit or Black Stools
- Not Passing Urine or Sudden Swelling All Over
- Severe Rash Spreading Rapidly With Mouth or Eye Involvement
- Sudden Breathlessness on Cancer Tablets: Go to Emergency or Wait?
- Sudden Confusion, Seizure or Weakness on One Side
- Sudden Severe Abdominal Pain: Ruling Out Perforation
- Sudden Vision Loss or Double Vision: What to Do Right Now
- Swollen, Painful Leg: Recognising a Blood Clot
- Uncontrolled Diarrhoea: The 6-Stool Rule Every Patient Should Know
- What to Tell an ER Doctor Who Doesn't Know Your Cancer Drug
- Yellow Eyes, Dark Urine or Severe Right-Sided Pain
Food, Drug & Supplement Interactions
- Antacids and Acidity Tablets Can Block Your Cancer Drug
- Anti-Nausea and Anti-Acidity Drugs That Prolong QT
- Anti-TB Treatment and Targeted Therapy: A Dangerous Combination
- Antibiotics and Antifungals That Interfere With Cancer Drugs
- Ayurvedic and Herbal Medicines With Targeted Therapy: The Real Risks
- Blood Thinners and Targeted Therapy: Managing the Bleeding Risk
- Contraceptive Pills and Hormone Medicines With Cancer Drugs
- Diabetes and Blood Pressure Medicines With Targeted Therapy
- Grapefruit, Pomegranate and Starfruit: Why They're Banned on Many Cancer Drugs
- Green Tea, Coffee and Caffeine on Targeted Therapy
- Homeopathy Alongside Targeted Therapy: What You Should Know
- How to Check Any New Medicine Against Your Cancer Drug
- Painkillers: Which Ones Are Safe on Targeted Therapy?
- Protein Powders and Immunity Boosters: Helpful or Harmful?
- Statins and Cholesterol Medicines During Cancer Treatment
- The Complete Do-Not-Take List for Common Targeted Therapy Drugs
- Turmeric, Ashwagandha, Giloy and Wheatgrass During Cancer Treatment
- Vaccines and Antivirals During Targeted Therapy
- Vitamin, Calcium and Iron Supplements During Treatment
Side Effects - General & Timeline
- Are Side Effects a Sign That the Drug Is Working?
- Side Effect Timeline: What Happens in Week 1, Month 1 and Month 6
- Targeted Therapy Side Effects: The Complete List by Drug Class
- Understanding Side Effect Grades 1 to 4 (In Plain Language)
- When to Call Your Oncologist Immediately: The Red Flag List
- Will a Dose Reduction Make My Treatment Less Effective?
Next step
Still not sure what applies to you?
Send your reports across and a senior medical oncologist will go through what they mean, what is known, and what the options actually are.
Common questions
Frequently asked questions
My echocardiogram showed a change in my EF. Does that mean my heart is damaged?
A change in EF on a monitoring scan does not mean permanent damage. It means the heart is pumping less efficiently than it was, and that finding is exactly what the scan is designed to catch early. For many patients on HER2-targeted therapy, function recovers once treatment is paused and the heart is supported with medication. What happens next depends on how much the EF has changed, whether you have symptoms, and how your heart responds. Ask your team to explain your specific result and what it means for your plan.
Will I need to see a cardiologist as well as my oncologist?
Quite possibly, and this is standard practice — not a sign that something has gone very wrong. ASCO and ACC guidance on cardio-oncology recommends specialist cardiac input when EF drops significantly or when a patient has symptoms. The cardiologist assesses how to support the heart and advises on whether and when targeted therapy can continue. Both specialists share responsibility in this situation. If your team has not mentioned a cardiology referral and you are concerned about your heart, it is entirely reasonable to ask.
How often will my heart be monitored during targeted therapy?
The schedule varies by the specific drug and your baseline heart health. For HER2-targeted drugs, echocardiograms are done before treatment starts and then at intervals during treatment — your team will give you the exact schedule. If your EF drops, scans become more frequent until the situation stabilises. If you are not sure when your next heart scan is, ask at your next appointment rather than waiting to be called.
Is the heart risk worse if I had chemotherapy before starting targeted therapy?
Certain chemotherapy drugs — particularly anthracyclines — also carry cardiac risk, and having received them before starting targeted therapy is something your oncologist and cardiologist take into account. The combined effect on the heart is tracked differently than with targeted therapy alone. Tell your team the full history of your previous treatment, including the names of drugs if you know them, so the monitoring plan reflects your complete cardiac history. If you are unsure which drugs you received before, your team can look this up.
If my EF recovers, can I restart targeted therapy?
Restarting is possible for many patients, and the decision is made jointly by your oncologist and cardiologist based on how much the EF has recovered, whether you had symptoms, and the balance of benefit from the cancer treatment against ongoing cardiac risk. Recovery on a scan does not automatically mean an immediate restart — the timing and conditions will be explained to you. Ask specifically: what does my EF need to show before restarting is considered, and how will that be reviewed?