The Clinical Significance Of Hs-CRP,LVEF And IVUS Features Of Atherosclerotic Plaques In Patients With Coronary Heart Disease

Objective The purposes of present study are as follows: 1) to investigate the morphological features as well as the vulnerability of atherosclerotic plaques through intravascular ultrasound ( IVUS) in patients with stable angina( SA) and patients with unstable angina(UA); 2) to elucidate the relation between the circulating level of high-sensitivity C-reactive protein(hs-CRP) and the vulnerability of coronary heart disease(CHD), the vulnerability of atherosclerotic plaques and the stenosis extent of coronary artery segment; 3) to elucidate the relation between the level of left ventricular ejection fraction(LVEF) and the vulnerability of CHD, the vulnerability of atherosclerotic plaques and the stenosis extent of coronary artery segment as well. Methods A clinical research was accomplished in 119 patients who were diagnosed as CHD initially. Research objects were divided into four groups: 30 patients in the control group with negative result in coronary angiography (CAG); 17 patients in SA group; 45 patients in UA group and 27 patients in acute myocardial infarction (AMI) group. Here were the concrete reseach methods. 1) Concentrations of hs-CRP were measured in all of the objects. 2) All were examined by CAG. At the same time, 30 persons in control group, 15 patients in SA group, 37 patients in UA group and 21 patients in AMI group underwent left ventricular angiography (LVA) right after CAG, measuring LVEF, end diastolic volume of left ventricle(LVEDV), end systolic volume of left ventricle(LVESV) and stroke volume(SV). 3) IVUS was used in 55 coronary ateries in 7 patients with SA and 29 patients with UA to analyze the coronary lesions. The detailed parameters involved external elastic membrane area(EEMA), luminal area(LA), plaque area(PA), area stenosis percentage, eccentric index (EI) and remodeling index(RI). Results 1) IVUS found that patients in SA group mainly had stable and fibrous plaques, while patients in UA group mainly had unstable and soft lipid plaques(p < 0.01). Nonetheless, fibrous plaques were also found in UA group(17/48,35.42%), mainly in 10 patients of low risky or medium risky subgroup. Calcific plaques were found in SA group as well as in UA group with no difference(p>0.05). EI were higher in UA group compared with SA group ( P < 0.05) , and coronary segments in UA group were prone to positive remodeling. 2) The plasma hs-CRP levels were gradually ascending from control group to AMI group. The hs-CRP level was higher in AMI group compared with UA group (p<0.05). And that was also higher in UA group compared with SA group (p<0.05). But there was no difference in the hs-CRP level between SA group and control group(p>0.05). The concentration of hs-CRP was significantly higher in unstable plaque group compared with stable plaque group (p<0.01), while there was no difference between slight stenosis group and medium-severe stenosis group(p>0.05). 3) The levels of LVEF were gradually descending from control group to AMI group. The LVEF level was significantly lower in AMI group compared with any of the other three groups (p<0.01). And the LVEF level was also significantly lower in UA group compared with control group(p<0.01). However, between UA group and SA group, SA group and control group, there was no diffenrence(p>0.05). In the mean time, the level of LVEF was significantly lower in medium-severe stenosis group compared with slight stenosis group (p<0.01), and there was no difference between stable plaque group and unstable plaque group. Conclusion 1) The majority of SA coronary artery lesions are stable plaques characterized by endocentric or eccentric but with low EI fibrous plaques. On the contrary, the majority of UA coronary artery lesions are mainly unstable plaques, which are more prone to positive remodeling, more eccentric and usually with large lipid pool or thin fibrosis cap. Calcific plaques are found in SA group as well as in UA group with no difference. 2) The circulating level of hs-CRP might reflect the unstable activity of CHD as well as the plaques, but has no relation with the stenosis extent of coronary artery segment. 3) The levels of LVEF are gradually descending in control group, SA group, UA group and AMI group. The LVEF level is significantly lower in AMI group compared with any of the other three groups. In patients with SA and patients with UA, the level of LVEF might reflect the stenosis extent of coronary artery segment, but has no obvious relation with thevulnerability of atherosclerotic plaques. LVEF might not be sensitive enough to predict early myocardium systolic dysfunction, the instability of CHD and that of atherosclerotic plaques.