| To explore the relation between left ventricular diastolic function abnormality and extent of myocardium ischemia and find a liminal value of coronary flow decrease for appearing to left ventricular diastolic function abnormality.methods: Echocardiographic examinations were performed in 13 dogs whose circumflex branch of coronary artery were constricted . Diastolic CK and DTI images were acquired both at SAX and A4C at 4 states, which are normal flow, flow is decreased to 509o of normal flow, flow is decreased to 25% of normal flow, and flow is decreased to 5% of normal flow. These CK images were analyzed by using computer with QCK software, regional area changes of diastole (RACd) and mean filling time (MFT)were calculated automatically. Velocity of E wave and A wave were measured on LVAW, LVPW, LVLAW, IVS and MVA both at SAX and A4C , and value of E/A were also calculated . result: (l)Results by CK: 145 (92. 95%)with high quality diastolic CK images that may be analyzed were acquired of 13 dogs. Value of RACd and MFT of the area supplied by circumflex branch of coronary arteryin control condition are respectively [from(45. 26?6. 47)% to (72. 08 ?7. 25)%] and [from (114. 33 ?. 11) ms to (130. 67 + 14. 46) ms]. Because circumflex branch of coronary artery were constricted, we compared value of the area supplied by circumflex branch of coronary artery in stenosis with that in control condition: In flow is decreased to 50% of normal flow, value of ischemia area have tendency to decrease, but they have no statistical significance, others have no significant difference between valve in this state and in control condition. In flow is decreased to 25% of normal flow, value of RACd and MFT of pst, lat, b-lt,m-lt and a-lt are respectively [from(24. 10 + 6.32)% to (39. 71 + 13. 86)%]and [from(97. 33 + 3. 21)ms to (102. 33 + 5. 51)ms], RACd and MFT are significantly lower than that of in normal, p<0. 05. in flow is decreased to 5% of normal flow, value of RACd and MFT of pst, lat, b~lt, m-lt and a-lt are respectively [from (9. 08 + 2. 96)% to (16. ll + 1.59)%]and [from(85. 00 + 5. 60)ms to (95. 50 + 5. 69)ms], RACd and MFT are significantly lower than that of in normal, p<0. 01. RACd of a-sp,m-sp and b-sp have the tendency to increase , in which b-sp has statistical significance, p<0.01. MFT of a-sp, m-sp, b-sp, inf and sp have the tendency to increase, but it have no statistical significance. (2)Results by DTI: In flow is decreased to 50% of normal flow, value of ischemia area have tendency to decrease, but they have no statistical significance, others have no significant difference between valve in this state and in control condition. In flow is decreased to 25% of normal flow, Velocity of E wave and A wave of LVLWdecreased , and they were lower than those in normal significantly, in which P of E <0. 001, P of A <0. 01, and value of E/A <1 ; Velocity of E wave and A wave of IVS increased, and they were higher than those in normal significantly, in which P of E <0. 05, P of A <0. 01; Velocity of E wave of MVA decreased , P<0. 01, and value of E/A<1; Velocity of E wave of LVPW decreased, P<0. 001, and value of E/A<1; Velocity of E wave of LVAW increased, P<0. 05. in flow is decreased to 5% of normal flow, movement of LVLW reversed to normal, and E wave and A wave integrated; Velocity of E wave and A wave of IVS increased, and they were higher than those in normal significantly, in which P of E <0. 01, P of A <0. 001; Velocity of E wave of MVA decreased , P<0. 001, and value of E/A<1; Movement of LVPW reversed to normal, and E wave and A wave integrated. Velocity of E wave and A wave of LVAW increased, in which P of E<0. 001, P of A<0. 01.conclusion: the relation between left ventricular diastolic function abnormality of dog and extent of myocardium ischemia can be gotten by QCK and DTI technology, and the liminal value of coronary flow for appearing to left ventricular diastolic function abnormality is flow decreased to 25% . It may offer reference to judge left ventricular diastolic function abnormality...
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