Multiple coronary stenoses secondary to atherosclerosis in an asymptomatic patient

Erasmo de la Peña Almaguer, MD1; Jorge Fernández de la Torre, MD1; María del Carmen Franco Cabrera, MS1; María Eugenia Díaz Sánchez, MD1; Miguel Franco Estradaa, MD1; Pâmela Bertolazzi, BS2

1 Department of Radiology, Hospital San José, Tecnológico de Monterrey, Monterrey, México

2 Siemens Healthineers, LAM

2/7/21
A 50-year-old male patient presented himself for a routine checkup. He has been a smoker for over 30 years (50 - 60 packs per year) and has been taking anti-depression pharmacotherapy for the past 20 years. His father, suffering from arterial hypertension, died from an acute myocardial infarction. The patient had a stress electrocardiogram (ECG) six years ago which showed no alterations. At the time of this checkup, he was asymptomatic and requested that a coronary CT angiography (cCTA) be performed.
cCTA images showed a right coronary artery (RCA) dominant system. A moderate stenosis, caused by non-calcified plaque, in the proximal left anterior descending artery (LAD), and a mild stenosis, caused by calcified plaque, in the middle LAD were seen. Three moderate stenoses in the proximal, middle and distal RCA, caused by calcified and non-calcified plaques, were also visualized. The circumflex artery (Cx) showed some irregularities along its course without any significant stenosis. The patient was referred to the cardiology department for consultation and thereafter began pharmacotherapy for coronary artery disease (CAD).
CT images show multiple stenoses in the left coronary artery, caused by calcified and non-calcified plaques.

Courtesy of Department of Radiology, Hospital San José, Tecnológico de Monterrey, Monterrey, México

Fig. 1: A curved MPR image (Fig. 1a), two axial images (Figs. 1b & 1c) and a thin MIP image (Fig. 1d) show a moderate stenosis, caused by non-calcified plaque, in the proximal LAD (arrows) and a mild stenosis, caused by calcified plaque, in the middle LAD (dotted arrows). The Cx (Fig. 1d, arrowhead) shows some irregularities without any significant stenosis.
CT images show multiple stenoses in the right coronary artery, caused by calcified and non-calcified plaques.
Courtesy of Department of Radiology, Hospital San José, Tecnológico de Monterrey, Monterrey, México
Fig. 2: A curved MPR image (Fig. 2a), three axial images (Figs. 2b-2d) and a thin MIP image (Fig. 2e) show three moderate stenoses in the proximal (arrows), middle (dotted arrows) and distal (arrowheads) RCA, caused by calcified and non-calcified plaques.
A cVRT image shows a three-dimensional coronary tree.
Courtesy of Department of Radiology, Hospital San José, Tecnológico de Monterrey, Monterrey, México
Fig. 3: A cVRT image shows a three-dimensional coronary tree.
CAD is an ischemic heart disease most commonly caused by atherosclerosis. It can potentially lead to a myocardial infarction with high morbidity and mortality rates. CAD often goes undetected since many patients remain asymptomatic until the first cardiac event occurs. A recent study suggested that cCTA could be reliably used for the early detection of clinically significant CAD in asymptomatic male individuals, particularly those with risk factors and a positive family history. [1] This case presents a similar clinical workup. A retrospective ECG gated spiral scanning is performed with 70 kV which enhances the image contrast while reducing the radiation dose and needing less contrast agent. This optimal kV setting can be applied to most cases since the operational output of the tube current allows up to 825 mA. The integrated mobile operation and fully automated workflow in the SOMATOM go platform grant the users great potential to deliver high performance – not only in routine cases, but also in more challenging ones. The fast acquisition time allows for extended clinical capabilities and optimal image quality with minimized motion artifacts.

Scanner

Scan area

Heart

Scan mode

Retrospective ECG gated spiral scan

Scan length

128 mm

Scan direction

Cranio-caudal

Scan time

9.5 s

Tube voltage

70 kV

Effective mAs

99 mAs

Dose modulation

CARE Dose4D

CTDIvol

17.6 mGy

DLP

290 mGy*cm

Rotation time

0.33 s

Pitch

0.2

Slice collimation

32 x 0.7 mm

Slice width

0.8 mm

Reconstruction increment

0.5 mm

Reconstruction kernel

Bv36

Heart rate

61 - 68 bpm

Contrast

370 mg/mL

Volume

80 mL + 40 mL saline

Flow rate

6 mL/s

Start delay

22 s defined by test bolus