Correlation of optimal angiographic viewing angles to body and heart types: A quantitative analysis

Yanqing WU; Meizhen XU; Yi LI; Xiaoshu CHENG; Junbing CHAI

ABSTRACT

BACKGROUND:

Coronary angiography is called "the golden standard" for the diagnosis of coronary heart disease (CAD). Foreshortening of vessel segments in angiographic projection images usually caused by the inappropriate projection angles or positions may lead to misdiagnosis or missed diagnosis.

OBJECTIVE:

To investigate the optimal angiographic views of main coronary artery and its branches in different somatotype or heart type patients and to investigate the specific relationships between the optimal angiographic views and the different somatotypes and heart types with computer-assisted techniques.

DESIGN:

A controlled observation.

SETTING:

Department of Cardiology, the Second Affiliated Hospital of Nanchang University.

PARTICIPANTS:

Altogether 1 369 patients were admitted to the Second Affiliated Hospital of Nanchang University to undergo coronary angiography from January 2001 to December 2006 and recruited for this study. Written informed consents of coronary angiography were obtained from all the patients. The protocol was approved by the Medical Ethics Committee of Medical College of Nanchang University.

METHODS:

All 1 369 inpatients were assigned into 3 groups by body mass index (BMI) fat somatotype group (n =489, BMI 26-31 kg/m2, transverse heart type), general somatotype group (n =502, BMI 23-25 kg/m2, general heart type), and thin somatotype group (n =378, BMI 17-22 kg/m2 vertical heart type). In each group, all arteries including left main coronary artery (LM), proximal segment of the anterior descending coronary artery (LAD), distal-mid segment of LAD, proximal segment of circumflex branch (LCX), distal-mid segment of LCX, proximal-mid and distal segments of right coronary artery (RCA) were properly and carefully analyzed using Compart software, and then we got its optimal angiographic viewing angle. Finally, we arranged these data and induced whether different somatotype group patients have different optimal angiographic viewing angles specifically for some coronary artery or not.MAIN OUTCOME

MEASURES:

Optimal angiographic viewing angles.

RESULTS:

All 1369 patients participated in the final analysis. Optimal angiographic viewing angle for LM left anterior oblique (LAO)(40±5)°/ caudal (CAU)(25±5)° or right left anterior oblique (RAO) 25°/CAU35°. In the fat somatotype group, the angle should be added 10° to its optimal angle, and in the thin somatotype group, the angle should be decreased by 10°, and the differences between the general somatotype group and the fat somatotype group or the thin somatotype group were statistically significant (all P < 0.05). Optimal angiographic viewing angle for proximal segment of LAD RAO (50±8)°/ cranial (CRA)(23±8)°. In the fat somatotype group, the optimal angle should be added 10°, but in the thin somatotype group, it should be decreased by 10°. The differences between the general somatotype group and the fat somatotype group or the thin somatotype group were statistically significant (all P < 0.05). Optimal angiographic viewing angle for distal-mid segment of LAD RAO (40±5)°/CRA (45±5)° or LAO (11±5)°/CRA (45±5)°. Optimal angiographic viewing angle for proximal segment of LCX LAO (45±5)°/CAU (35±5)° or anteroposterior (AP)/CAU36°. Optimal angiographic viewing angle for distal-mid segmental of LCX LAO (45±5)°/CAU (35±5)° or RAO (6±4)°/CAU (30±5)°. Optimal angiographic viewing angle for proximal-mid segment of RCA LAO (35±5)°/CAU (14±5)° or LAO (48±5)°/CRA (15±5)°. For the thin or fat somatotype group, the optimal LAO angle should be increased by 15°, the optimal RAO angle should be decreased by10° for fat somatotype group and should be increased by 10° for thin somatotype group, and the differences between the general somatotype group and the fat somatotype group or the thin somatotype group were statistically significantly (P < 0.05). Optimal angiographic viewing angle for distal segment of RCA LAO (53±5)°/CAU (17±5)°.

CONCLUSION:

The message can be got clearly about the whole coronary artery and the accuracy percentage of stenosis by changing angiographic viewing angle regularly to its own optimal angle in different somatotype or heart type patients. It's very important for making the choice of diagnosis and therapy