What are the indications for a pre‑operative transthoracic 2‑dimensional echocardiogram in a breast‑cancer patient undergoing mastectomy?

Indications for Pre-operative 2D Echocardiography in Breast Cancer Patients Undergoing Mastectomy

Pre-operative 2D echocardiography is indicated in breast cancer patients scheduled for mastectomy only if they will receive potentially cardiotoxic cancer therapy (anthracyclines and/or trastuzumab/HER2-targeted agents), have pre-existing cardiovascular risk factors, or exhibit clinical signs or symptoms concerning for cardiac dysfunction. 1

When Echocardiography IS Indicated Before Mastectomy

Planned Cardiotoxic Therapy

• Baseline echocardiography is essential before initiating anthracyclines and/or trastuzumab in the adjuvant or neoadjuvant setting to establish left ventricular ejection fraction (LVEF) and serve as a reference for subsequent surveillance. 1
• This applies to HER2-positive breast cancer patients who will receive trastuzumab, pertuzumab, or other HER2-targeted therapies. 1, 2
• The baseline LVEF measurement determines eligibility for cardiotoxic therapy and guides treatment decisions throughout the cancer care continuum. 1

High-Risk Patient Characteristics

Perform baseline echocardiography if the patient has any of the following cardiovascular risk factors: 1

• Age ≥60 years
• Pre-existing cardiac disease (prior myocardial infarction, heart failure, valvular disease)
• Hypertension (blood pressure ≥140/85 mmHg)
• Diabetes mellitus
• Obesity
• History of chest radiation
• Significant arrhythmias on ECG (atrial fibrillation, heart block)
• ECG evidence of left ventricular hypertrophy or prior infarction

Clinical Signs or Symptoms

Echocardiography is strongly recommended for diagnostic workup in any patient with clinical signs or symptoms concerning for cardiac dysfunction, including: 1

• Shortness of breath or decreased exercise tolerance
• Chest pain
• Ankle swelling or pedal edema
• Palpitations
• Fainting or lightheadedness
• Elevated jugular venous pressure on examination
• Cardiac murmurs suggesting valvular disease
• Pulmonary crackles suggesting heart failure

When Echocardiography is NOT Routinely Indicated

For patients undergoing mastectomy alone without planned adjuvant chemotherapy or HER2-targeted therapy, and without cardiovascular risk factors or symptoms, routine pre-operative echocardiography is not indicated. 1

Surgery-Only Scenarios

• Patients with early-stage, hormone receptor-positive, HER2-negative breast cancer who will receive only endocrine therapy (tamoxifen, aromatase inhibitors) do not require baseline cardiac imaging. 1
• Patients undergoing mastectomy for ductal carcinoma in situ (DCIS) without planned systemic therapy do not need routine echocardiography. 1

Optimal Imaging Protocol When Indicated

Technical Specifications

Two-dimensional transthoracic echocardiography with Doppler is the surveillance imaging modality of choice, measuring: 1

• LVEF using biplane method of discs (Simpson's method)
• Left ventricular end-diastolic and end-systolic dimensions
• Right ventricular size and function (fractional area change)
• Valvular function and presence of significant valvular disease
• Pulmonary artery pressure estimation from tricuspid regurgitation velocity

Advanced Imaging Considerations

• Three-dimensional echocardiography provides more accurate LVEF measurements (temporal variability 6% vs. 10% for 2D) and should be used when available. 1, 3
• Global longitudinal strain (GLS) measurement should be included as it detects subclinical myocardial dysfunction before LVEF decline and predicts subsequent cardiotoxicity. 1, 4
• A baseline GLS <19% or subsequent ≥15% relative reduction in GLS is predictive of cardiotoxicity development. 1

Alternative Modalities

If echocardiography is not available or technically feasible (poor acoustic windows, severe obesity), use: 1

• Cardiac MRI (preferred alternative) - provides detailed anatomic and functional information without radiation exposure
• MUGA scan - accurate LVEF measurement but provides limited additional cardiac information and involves radiation exposure

Critical Pitfalls to Avoid

Common Errors

• Do not assume all breast cancer patients need pre-operative echocardiography - this leads to unnecessary testing and healthcare costs in low-risk patients not receiving cardiotoxic therapy. 1
• Do not delay baseline imaging until after surgery if cardiotoxic therapy is planned - the baseline must be established before any potentially cardiotoxic exposure. 1
• Do not use inconsistent imaging modalities for serial monitoring - switching between echocardiography and MUGA introduces measurement variability that can be misinterpreted as true LVEF changes. 1

Documentation Requirements

• Record blood pressure at the time of echocardiography, as afterload affects measured LVEF and regurgitant lesion severity. 1
• Document the specific LVEF measurement method used (biplane Simpson's, 3D volumetric) to ensure consistency in follow-up studies. 1
• Identify any baseline abnormalities (valvular disease, left ventricular hypertrophy, diastolic dysfunction) that may influence cardiotoxicity risk. 1

Risk Stratification Framework

Patients are considered at increased risk for cardiac dysfunction if they have: 1

• Planned cumulative anthracycline dose >250 mg/m² doxorubicin equivalent
• Combination anthracycline plus trastuzumab therapy
• Age ≥60 years with any cardiotoxic therapy
• Two or more cardiovascular risk factors (hypertension, diabetes, obesity, smoking)
• Prior chest radiation involving the heart
• Pre-existing cardiac disease with LVEF 50-55%

These high-risk patients require baseline echocardiography before initiating therapy and more intensive surveillance during and after treatment. 1, 5