OBJECTIVETo study the Chinese medical syndrome characteristics of the miniature pig model of coronary heart disease (CHD) made by chronic myocardial ischemia, and its correlation with heart structure and function.

METHODSChinese miniature pigs were randomly divided into two groups, 18 in the model group and 8 in the sham-operation group. CHD model was established by placing Ameroid narrow ring in the left anterior descending artery of pigs to induce chronic myocardial ischemia. Characteristics of Chinese medical syndrome in the model were evaluated 8-12 weeks after modeling by observing the general condition, tongue color, activity, hemorrheologic figures, electrocardiogram, coronary angiography, etc., as well as the cardiac structure and function detected by echocardiogram.

RESULTSCompared with the sham-operation group, the modeled pigs showed, at end of the 8th week, pink purple tongue; decreased tail wagging frequency (P < 0.05 or P < 0.01); increased plasma and reduction viscosities (P < 0.05); and raised rigidity index (P < 0.01), with the stenosed diameter of coronary artery reaching 99%. Besides, echocardiogram showed decreased thickness of left ventricular end-systolic stage, end-diastolic stage and inter-ventricular septum end-diastolic stage; lowered ejection fraction and fractional shortening rate (P < 0.05 or P < 0.01), and dilated left ventricular end-diastolic diameter and left ventricular end-systolic diameter. The motion of ventricular wall was decreased orderly in levels from the mitral valve to the papillary muscle to the apex of heart.

CONCLUSIONSCHD pig model made by chronic myocardial ischemia showed a Chinese medical qi-deficiency & blood-stasis syndrome. It indicated that a syndrome transition and conversion progress from blood-stasis to qi-deficiency & blood stasis occurred in the model animals at the 4th to 12th week. The created model provided a reliable basis for further studying rules of syndrome transition and conversion between qi deficiency and blood stasis, as well as on the Chinese medical theory of "blood is mother of qi".