A noninvasive radiographic technique for evaluation of exercise-induced changes in cardiac function

Area of Science:

• Cardiology
• Radiology
• Diagnostic Imaging

Background:

• Coronary artery disease (CAD) diagnosis often relies on stress testing.
• Traditional stress tests may have limitations in detecting subtle cardiac changes.
• Electrocardiographic-triggered radiography offers a potential new imaging modality.

Purpose of the Study:

• To evaluate an electrocardiographic-triggered radiographic technique for detecting stress-induced cardiac changes.
• To assess changes in systolic and diastolic cardiac transverse diameter and left ventricular wall motion during exercise.
• To compare the technique's findings with multigated radionuclide blood pool scans in patients with and without CAD.

Main Methods:

• Utilized an electrocardiographic-triggered radiographic technique during upright bicycle exercise.
• Acquired single images of the heart at end-systole and end-diastole.
• Studied 21 patients (10 normal, 11 with CAD); 20 also underwent radionuclide scans.

Main Results:

• Patients with CAD showed increased systolic cardiac transverse diameter during exercise (p<0.001).
• 73% of CAD patients exhibited abnormal cardiac dimensions or left ventricular wall motion.
• Radionuclide scans revealed abnormal ejection fraction response in 80% of CAD patients.

Conclusions:

• The electrocardiographic-triggered radiographic technique is inexpensive and easy to perform.
• Preliminary data suggest its utility as an adjunct to cardiac stress testing.
• Further research is warranted to validate this imaging approach for CAD detection.