Reliable In-Stent Lumen Visualization With Dual Source CT Coronary Angiography

HISTORY

A 58-year-old man with a history of hypertension and hypercholesterolemia was admitted to the hospital with symptoms of suspected stable angina pectoris. The patient was referred to conventional coronary angiography after a positive exercise-ECG test. Conventional angiography showed significant stenoses at the level of the proximal right coronary artery (RCA) and the proximal left anterior descending coronary artery (LAD). Percutaneous intervention was undertaken and one bare-metal stent in the RCA and two overlapping bare-metal stents in the LAD were successfully implanted. The patient was referred to follow-up CT coronary angiography after 18 months.

DIAGNOSIS

The patient was scanned on a Dual Source CT (DSCT) scanner. Nitroglycerine was administered prior to the CT scan; however, the patient did not receive prescan beta-blockers. The patient had a heart rate of 76 beats/minute during the CT scan. DSCT coronary angiography was able to reliably rule out the presence of in-stent restenosis in both the RCA and LAD stents.

PROTOCOL

Scanner SOMATOM Definition
Scan area Heart
Scan length 103 mm
Scan time 7,3 sec
Scan direction Caudo-cranial
Heart rate 76 bpm
kV 120 kV
mAs / Rot 400 mAs/rot
Rotation time 0.33 sec
Temporal resolution HR independent 83 msec
Slice collimation 0.6 mm
Spatial resolution 0.33 mm
Pitch 0.32
Reconstructed slice thickness 0.75 mm
Increment 0.4 mm
Prospective ECG-tube modulation On, window: 30–60%
CTDIvol 45,31 mGy
Kernel B46f
Contrast material volume 90 ml
Flow rate 5,5 ml/s
Bolus tracking On

Volume-rendered CT image (Fig. 1) showing the stents in the proximal-to-mid LAD and the mid part of the RCA.

Curved multiplanar CT images showing excellent visualization of the in-stent lumen of both the RCA (Fig. 2) and LAD (Fig. 3) stents, thereby reliably ruling out the presence of in-stent restenosis.

Curved multiplanar CT images showing excellent visualization of the in-stent lumen of both the RCA (Fig. 2) and LAD (Fig. 3) stents, thereby reliably ruling out the presence of in-stent restenosis.