OBJECTIVETo study the effect of shensongyangxin capsule on myocardial remodeling and ventricular fibrillation characteristics in rat with coronary artery ligation.

METHODTwenty-three male rats were randomly divided into sham-group (n = 5), model group (n = 6), anmiodarone group (n = 6) and shensongyangxin capsule group (n = 6). Drugs were administrated after modeling of 2 days, lasting four weeks. Two dimensional and Doppler images were acquired by a 15 MHz high-frequency linear ultrasound transducer at 4 weeks after operation, and chest was opened to detect ventricular fibrillation threshold value and persistent time.

RESULTAfter administration of four weeks, echocardiogram was detected. Compared with model group, shensongyangxin capsule group diastasis interventricular septum thickness (IVSTd) and left ventricle diameter (LVDd) were significiently different between them (1.20 +/- 0.49) vs (0.78 +/- 0.08) mm and (6.77 +/- 1.34) vs (7.95 +/- 0.92) mm, (P < 0.01 and 0.05); echocardiogram result had no difference in amiodarone and model groups (P > 0.05). LVMI measured by practicion was different between shensongyangxin capsule and model groups: (17.12 +/- 1.91) vs (18.95 +/- 1.41) g x m(-2), (P < 0.05), while amiodarone group had no difference compared with model group. Electrophysiology was used to detect ventricular fibrillation threshold value and 1-5, 6-10, 11-15 V three stages' ventricular fibrillation threshold persistent time were significiently different among each group (P < 0.01), 16-20 V stage's ventricular fibrillation persistent time were also different among each group (P <0.05). Sample "average ranks" showed ventricular fibrillation threshold value of amiodarone group and shensongyangxin capsule group were four times than model group; and amiodaron group had best effect of holding-back ventricular fibrillation persistent time.

CONCLUSIONThe coronary artery ligation can result in myocardial remodeling by increasing volume load, and at the same time influencing electrophysiology function of heart. Amiodaron elevated ventricular fibrillation threshold of heart, this effect maybe relate to influencing many ion channels of myocardial cellular membrane; shensongyangxin capsule also elevate ventricular fibrillation threshold of heart, this effect maybe also relate to influencing many ion channels of myocardial cellular membrane, and on the other hand this effect maybe relate to hold-back ventricular remodeling after coronary artery was ligated, accordingly improve electrophysiological base material of heart.