When should an echocardiogram (echo) be ordered for a patient with tachycardia?

When to Order Echocardiography for Tachycardia

Order an echocardiogram immediately for any patient with tachycardia who has suspected structural heart disease, hemodynamic instability, persistent unexplained tachycardia, new conduction abnormalities, or signs/symptoms suggesting cardiac dysfunction. 1

Immediate Echocardiography Required

Ventricular Tachycardia or Suspected Ventricular Arrhythmias

• Echocardiography is mandatory for all patients with ventricular arrhythmias suspected of having structural heart disease. 1
• Order echo for patients at high risk for serious ventricular arrhythmias including those with suspected dilated cardiomyopathy, hypertrophic cardiomyopathy, right ventricular cardiomyopathy, or acute MI survivors. 1
• Echo helps identify left ventricular systolic dimensions >4 cm, which predicts 2.5 times higher risk of ventricular tachycardia episodes. 2

Trauma-Related Tachycardia

• Perform focused cardiac ultrasound immediately in patients with isolated chest trauma presenting with hypotension and tachycardia to exclude pericardial tamponade or tension pneumothorax. 1
• Emergency echo is necessary for chest trauma patients with persistent tachycardia or hypotension even without tamponade, as unexplained persistent tachycardia raises suspicion of cardiac injury. 1

Post-Procedural Tachycardia

• Order echo as first-line examination for hemodynamic instability and/or inadequate cardiac output following cardiac surgery or catheter laboratory intervention. 1

Echocardiography Reasonable in Selected Cases

Supraventricular Tachycardia with Concerning Features

• Order echo for patients with tachycardia accompanied by signs of heart failure, abnormal auscultatory findings, abnormal ECG tracings, or recurrent arrhythmias. 1
• Echo is appropriate for patients with palpitations, presyncope, or syncope when signs or symptoms of cardiovascular disease are present (e.g., suspected aortic stenosis, hypertrophic cardiomyopathy, heart failure). 1

Persistent or Incessant Tachycardia

• Persistent tachycardia lasting weeks to months can cause tachycardia-induced cardiomyopathy, which is reversible but requires echocardiographic assessment. 3, 4, 5
• Patients with pure tachycardia-induced cardiomyopathy typically present with smaller left ventricular dimensions compared to dilated cardiomyopathy patients, but echo is essential for diagnosis and monitoring. 5
• Even after tachycardia control, these patients show persistent adverse left ventricular remodeling requiring long-term echocardiographic follow-up. 3, 5

Pediatric Tachycardia

• An echocardiogram is recommended for children with tachycardia to exclude structural heart disease including hypertrophic cardiomyopathy, dilated cardiomyopathy, valvular abnormalities, and coronary artery anomalies. 3

When Echocardiography is NOT Indicated

Simple Sinus Tachycardia Without Red Flags

• Do not order routine cardiac imaging for asymptomatic sinus bradycardia or first-degree atrioventricular block without clinical evidence of structural heart disease. 1
• In patients with minor chest injuries and no tachycardia, hypotension, respiratory difficulty, chest pain, or other concerning symptoms, clinical assessment alone may be sufficient. 1
• For sinus tachycardia with rates <150 bpm in the absence of ventricular dysfunction, the tachycardia is likely secondary to an underlying condition (fever, dehydration, anemia, hyperthyroidism) rather than primary cardiac pathology. 3

Critical Clinical Pitfalls

Avoid Treating the Number

• When cardiac function is poor, cardiac output can be dependent on rapid heart rate; "normalizing" the heart rate in compensatory tachycardia can be detrimental. 3
• Always identify and treat the underlying cause of sinus tachycardia rather than the heart rate itself. 3

Don't Miss Tachycardia-Induced Cardiomyopathy

• Recurrent tachycardia after initial control results in precipitous decline in left ventricular ejection fraction, making echo surveillance critical. 5
• Echocardiography use is associated with more intensive medical therapy and improved three-year overall mortality (HR 0.61) and cardiovascular mortality (HR 0.52) in heart failure patients. 6

Recognize High-Risk ECG Patterns

• If the 12-lead ECG shows pre-excitation (delta waves), prolonged QT interval, Brugada pattern, new bundle branch block, or wide complex tachycardia of unknown origin, order echo and refer to cardiology immediately. 3