Learn how to choose the right cardiac diagnostic test using risk assessment and symptom-driven strategies.

Published: January 23, 2026

When patients present with cardiac symptoms, choosing the right cardiac diagnostic test depends on risk stratification, symptom frequency and clinical context. Here is a practical guide to navigating cardiology testing in primary care, adapted from a continuing medical education presentation by Mostafa O. El-Refai, M.D., interventional cardiologist with Norton Heart & Vascular Institute.

Chest pain: Start with risk assessment

Most patients with chest pain do not have conditions such as heart failure or obstructive coronary artery disease. Many symptoms, such as chest pain, mimic those of cardiovascular disease but can be the result of gastrointestinal issues, panic and anxiety, and respiratory conditions. Before ordering cardiac diagnostic tests, evaluate age, gender, risk factors and symptom characteristics to determine pretest probability.

The American College of Cardiology (ACC) guidelines recommend starting with an electrocardiogram (EKG) for initial evaluation, though 5% of acute myocardial infarctions demonstrate no EKG changes. Transthoracic echocardiography serves as a useful screening test, revealing pericardial effusions, regional wall motion abnormalities and left ventricular ejection fraction without radiation exposure.

For low-risk to intermediate-risk patients, exercise treadmill testing remains a reasonable first-line modality. The Bruce protocol provides metabolic equivalent data and EKG changes during physiologic stress. Patients who achieve target heart rate and appropriate metabolic equivalents for age without ischemic changes generally have favorable prognoses.

Adding imaging for better sensitivity

Single-photon emission computed tomography (SPECT) and stress echocardiography add imaging to standard exercise testing. SPECT uses radiotracer injection to assess myocardial perfusion, while stress echocardiography evaluates regional wall motion abnormalities. Both are functional tests assessing myocardial blood flow rather than coronary anatomy.

SPECT imaging can produce artifacts from breast tissue, diaphragmatic attenuation or gastrointestinal tracer uptake. Positron emission tomography (PET) myocardial perfusion imaging helps reduce these artifacts in patients with elevated body mass index or prior equivocal studies.

Stress echocardiography requires adequate acoustic windows. Dobutamine serves as the pharmacologic stress agent but can precipitate arrhythmias or hemodynamic instability, making it less favorable than exercise-based protocols when patients have functional capacity.

Coronary CT angiography: The rising star

For patients under 65 with low-to-intermediate pretest probability, coronary CT angiography (CCTA) now represents a Class I recommendation in ACC guidelines. Unlike functional tests, CCTA provides direct visualization of coronary anatomy and can detect nonobstructive atherosclerotic disease — valuable for risk stratification and intensification of medical therapy in younger patients.

The test requires heart rate control, typically below 75 beats per minute with beta-blocker pretreatment. Coronary artery calcium (CAC) scores above 400 to 600 limit diagnostic accuracy due to blooming artifact. CT-derived fractional flow reserve can now determine hemodynamic significance of intermediate stenoses noninvasively.

Palpitations: Match monitor duration to symptom frequency

Most individuals experience premature atrial contractions and premature ventricular contractions. Ectopic burden under 1% is physiologic; under 5% rarely requires intervention.

Choose monitoring duration based on symptom frequency. Holter monitors are optimal for daily symptoms. Ambulatory event monitors lasting one to four weeks are appropriate for weekly symptoms. For infrequent symptoms occurring every few months, patient-activated devices like KardiaMobile or smartwatch ECG applications may capture events, though use caution in patients with health anxiety who may overuse these devices.

Lightheadedness and syncope

Most lightheadedness and syncope presentations are noncardiac in etiology. Orthostatic hypotension represents autonomic dysfunction, and vasovagal syncope accounts for most syncopal episodes.

When cardiac causes require exclusion, order ambulatory monitoring matched to symptom frequency plus transthoracic echocardiography to assess for structural abnormalities, including aortic stenosis or hypertrophic obstructive cardiomyopathy. For unexplained recurrent syncope, electrophysiology consultation can place an implantable loop recorder with three-year battery life.

Edema evaluation

Remember that chronic venous insufficiency, not heart failure, causes most bilateral lower extremity edema. When cardiac etiologies require exclusion, B-type natriuretic peptide and transthoracic echocardiography provide reasonable initial workup.

Advanced imaging, including cardiac MRI and transesophageal echocardiography, typically require cardiology referral for specific clinical indications.

Clinical pearls

• Compare serial EKGs. Repeat EKGs can establish a baseline for atients with chronically abnormal electrocardiograms and otherwise stable findings. Left ventricular hypertrophy with strain pattern unchanged over five years has different clinical significance than acute ST-segment changes.
• Use calcium scoring for risk stratification. A 40-year-old with LDL cholesterol level 140 mg/dL and CAC score of 0 often can defer statin therapy. A CAC score of 50 in the same patient indicates subclinical atherosclerosis warranting aggressive lipid management even without flow-limiting stenoses.
• Match the monitor to symptom frequency. Ambulatory monitoring during asymptomatic periods doesn’t answer the clinical question. If palpitations occur weekly, order a two-week event monitor rather than 24-hour Holter monitoring.
• Exercise preferred over pharmacologic stress when feasible. While stress echocardiography with treadmill exercise offers good diagnostic yield, pharmacologic stress with dobutamine can precipitate atrial fibrillation with rapid ventricular response or ventricular arrhythmias. For patients unable to exercise, nuclear SPECT with regadenoson provides safer pharmacologic stress.
• Coronary CT angiography requires adequate preparation. Heart rates above 75 beats per minute produce motion artifact compromising diagnostic accuracy. Order metoprolol 50 to100 milligrams one hour prescan and confirm adequate rate control. Patients with chronic sinus tachycardia or uncontrolled atrial fibrillation are poor candidates.
• Interpret artifact reports appropriately. When nuclear studies report “soft tissue attenuation” or “inferior wall artifact secondary to diaphragmatic attenuation,” the study has technical limitations. In patients with high pretest probability, consider PET myocardial perfusion imaging or proceed directly to invasive coronary angiography rather than repeating SPECT.
• Objective testing reduces anxiety. Low-risk patients with atypical chest pain often benefit from diagnostic testing for reassurance rather than diagnosis. A negative stress test in appropriate clinical context provides therapeutic benefit beyond medical management.
• Functional versus anatomic testing. Stress tests (nuclear, echocardiogram, exercise ECG) assess physiologic significance of stenoses but miss nonobstructive disease. CCTA visualizes plaque burden, including subclinical atherosclerosis, informing aggressive preventive strategies in young patients.

The bottom line

Successful cardiac diagnostic testing begins with appropriate risk stratification using clinical presentation, age, gender and cardiovascular risk factors. Match test selection to pretest probability, patient characteristics and symptom patterns. When clinical suspicion remains elevated despite negative noninvasive testing, escalate to invasive evaluation. Most importantly, remember that negative testing in truly low-risk patients may cause more harm than benefit through incidental findings and downstream procedures.