Which imaging modality is most reliable for evaluating left ventricular systolic function?

• A. Chest X-ray
• B. Transthoracic echocardiography
• C. CT angiography
• D. Stress test

Answer: (B)

Evaluating left ventricular systolic function means measuring how well the ventricle contracts and ejects blood, usually quantified by the ejection fraction and by how the walls move during contraction. Transthoracic echocardiography uses ultrasound to visualize the heart in motion, giving direct, real-time assessment of LV size, wall thickening in systole, and precise EF measurements from multiple views with Doppler analysis. It’s noninvasive, widely available, can be performed at the bedside, and doesn’t involve radiation, making it the most reliable and practical way to gauge LV systolic function.

Chest X-ray can hint at heart size but doesn’t quantify how well the ventricle contracts. CT angiography focuses on anatomy and coronary arteries and involves radiation and contrast, not precise functional assessment. A stress test evaluates how the heart performs under increased workload but isn’t the primary method for measuring resting systolic function.