Cardiac evaluation before surgery

Why the heart is assessed before an operation

Every operation, even a small one, places a load on the body: there is stress, blood loss, changes in blood pressure and rhythm, and pain and inflammation after the procedure. A healthy heart copes without problems, while a heart with undiscovered or untreated disease may have cardiac complications such as a heart attack, rhythm disturbances or heart failure.

The evaluation before surgery has three aims: (1) to estimate how high the risk is, (2) to find and treat conditions that can be improved before the procedure, and (3) to adjust medicines and monitoring around the operation. It is teamwork between the surgeon, the anesthesiologist, the cardiologist and the patient, not the decision of one doctor.

Risk has two parts: the risk of the procedure itself (an eye operation or an arthroscopy is considered low risk; major abdominal, chest or vascular surgery is higher risk) and the patient’s own risk (heart and other diseases, age, general condition).

Does every patient need a cardiology visit

No. Many healthy patients having low-risk procedures do not need a cardiology consultation or extensive tests. The anesthesiologist and the surgeon decide the need based on the history, the examination and, when appropriate, an ECG.

Cardiac evaluation is especially helpful when:

• there are symptoms suggesting heart disease: chest pain or pressure, dyspnea, palpitations, fainting, swollen legs;
• there is known cardiovascular disease: a previous heart attack, a stent or bypass, heart failure, valve disease, arrhythmias (for example atrial fibrillation), a pacemaker or defibrillator;
• there are several risk factors (diabetes, high blood pressure, kidney disease, lung disease, older age) and limited physical activity;
• the procedure is high-risk or major.

The doctor may use standardized risk tools (for example the Revised Cardiac Risk Index, RCRI, or calculators based on surgical data), which combine the planned procedure with the patient’s conditions.

Ability to be active: a simple and powerful indicator

One of the most useful questions is a simple one: how active are you in daily life? The doctor usually tries to find out whether you can do effort equal to about 4 metabolic equivalents (METs), for example climbing two flights of stairs or walking briskly on level ground without being stopped by dyspnea, chest pain or marked fatigue.

If you can do this without symptoms, the risk of cardiac complications is usually lower and additional tests are often not needed. If you cannot, or are not sure, this is a signal for more careful assessment. It is important to answer honestly, even if it feels unusual to talk about “walking” before an operation.

What the cardiologist reviews

• Heart history: symptoms, diagnoses, previous procedures (stent, bypass, ablation), the tests you have had and when.
• Other conditions: diabetes, kidney, lung and thyroid disease, sleep apnea, a previous stroke.
• Medicines and supplements, including over-the-counter ones, anticoagulants, antiplatelet drugs, and medicines for diabetes and blood pressure.
• Physical examination: blood pressure, pulse, heart, lungs, signs of fluid (swelling).
• The planned procedure: type, urgency, duration, risk of bleeding and type of anesthesia.

You should be sure to report: a coronary stent (and when it was placed), a previous heart attack, heart failure, valve disease, arrhythmias, implanted devices and any previous reaction to anesthesia.

Which tests may be needed

Additional tests are not automatically recommended for every patient. A test is useful only when its result can change the decision or the care around the operation. Unnecessary tests can delay the procedure, cause anxiety and lead to further tests without benefit.

• Resting ECG: a baseline for comparison and for the rhythm; helpful in patients with known cardiovascular disease or symptoms, and for higher-risk procedures.
• Echocardiography: when there is known heart failure or a change in it, a new murmur with symptoms, unexplained dyspnea, or a known valve problem with consequences, and when there is no up-to-date echocardiogram. It is not needed routinely in patients without signs and without known disease.
• Blood tests: hemoglobin, kidney function, electrolytes, glucose/HbA1c, and, as appropriate, cardiac markers such as BNP or NT-proBNP.
• Tests for ischemia (exercise or pharmacologic stress, with imaging) are not routine. They are recommended only in selected patients, for example when risk is high and ability to be active is low, and the result will change management. These tests are not offered at our clinic, but may be recommended to you at a suitable center when indicated.
• Coronary angiography or revascularization before surgery are done only when the same indication would exist without the operation (for example acute coronary syndrome or severe angina); they are not done to “protect” the operation in patients with stable coronary disease.

What happens with medicines

The main rule: do not stop any medicine on your own. Some medicines should be continued, others should be stopped or changed before the operation. The instructions are given individually by the medical team, according to the procedure, the risk of bleeding and the risk of thrombosis. Examples of usual practice:

• Beta-blockers: if you have taken them for a long time, they are usually continued without interruption. Starting them newly only on the day of surgery is not recommended.
• Statins: usually continued.
• Blood pressure medicines (ACE inhibitors, angiotensin receptor blockers): some teams stop them a day before the operation to avoid low blood pressure during anesthesia; the decision is made by the anesthesiologist.
• SGLT2 inhibitors (a group of medicines for diabetes and heart failure): usually stopped a few days before surgery (about 3–4 days) because of the risk of ketoacidosis.
• Anticoagulants (warfarin or the newer oral drugs) are stopped some days before the procedure, depending on the drug and kidney function. “Bridging” with heparin is generally not recommended, except in special high-thrombotic-risk cases (for example a mechanical mitral valve, a recent clot in the left ventricle, atrial fibrillation with a recent stroke).
• Antiplatelet drugs and stents: the timing of the procedure after a stent and whether to continue aspirin or other drugs are decided individually, because early interruption can cause stent thrombosis, while continuing can increase bleeding. Ask the doctor who placed the stent.
• Diabetes: insulin and other medicines are adjusted according to the fasting schedule.

What conclusion the evaluation gives

The report describes the cardiovascular condition, the estimated risk and the recommendations for care around the operation. The outcome may be:

• the procedure can go ahead as planned, with a plan for medicines and monitoring;
• additional assessment or treatment is needed before the procedure (for example control of blood pressure, rhythm or heart failure, or an update of a test);
• the procedure or its timing should be reconsidered: if urgent, it proceeds with the best possible care; if elective and risk is high, alternatives and delay are discussed.

The evaluation does not guarantee the absence of complications. Its aim is to lower the risk and to make sure the decision is made with full information, together with the surgeon, the anesthesiologist and the patient. You have the right to ask about your risk and about alternatives.

After the operation

Care continues after the procedure. Some patients have damage to the heart muscle without pain (found only through blood tests) or new atrial fibrillation. If a rhythm disturbance is found after surgery, it is followed by a cardiology assessment, often as an outpatient, and a decision on anticoagulation according to the risk of stroke. If after discharge you have chest pain, new dyspnea, palpitations, swelling or fainting, contact your doctor, or 127 if they are severe.

What to bring to the visit

• Information about the operation: type, planned date and the surgeon.
• The full list of medicines and supplements, with doses.
• Previous ECG, echocardiogram, Holter and blood tests.
• Documents about stents, heart operations or implanted devices (pacemaker, defibrillator), with dates.
• Your questions for the team.

It is best to have the visit as early as possible when the operation is planned, so that there is time for any adjustments.