The Impact Of Percutaneous Coronary Intervention Therapy On The Coronary Microcirculation In Stable Angina Patients

Background:Percutaneous coronary intervention (PCI) is a widely used method which can restore coronary artery blood flow. It has become the cornerstone treatment for ischemic heart disease. Although coronary angiography indicates that the coronary artery has been reopened, the myocardial tissue continues to prime weak or no perfusion of the coronary microcirculation after PCI in some acute myocardial infarction (AMI) patients. Altered perfusion in the coronary microcirculation indicates poorer prognosis with respect to cardiovascular events and mortality. Therefore, many clinicians have begun to focus on the perfusion of the coronary microcirculation.However, the current technology can not directly observe in humans coronary microvascular. Traditional noninvasive assessment of microcirculation methods including coronary flow reserve (CFR), contrast-enhanced cardiac magnetic resonance (ceCMR), coronary angiography and flow imaging to determine myocardial contrast echocardiography (MCE) and ECG ect. However, these methods for assessment of the microcirculation has some limitations, such as some relatively complex measurement, only qualitative assessment of the microcirculation, the results of the analysis of subjective factors greater, or not to conduct an independent assessment of the microcirculation.Index of microcirculatory resistancet (IMR) is a new parameter to evaluate the coronary microcirculation in recent years. Compared with other traditional methods, it can be measured in interventional therapy and quantitatively microcirculation resistance value when measured against the impact of coronary artery stenosis. The detection of IMR is relatively simple and reproducible. The theoretical basis of IMR is Ohm’s laws, in which IMR is defined as the maximum congestive heart when under pressure divided by the reciprocal of the narrow distal vessel transit time, transit time can be expressed simply multiply within a narrow distal vessel pressure. IMR is obtained by the actual measurement set with pressure/temperature sensors in the guide wire in coronary interventional procedures.Recent studies have found that in STEMI patients post PCI, higher IMR values were associated with high incidence of major adverse cardiac events. McGeoch selected57cases of patients with STEMI, and measured the IMR value after primary PCI or rescue PCI, then assessed the presence or absence of left ventricular function and the degree of microvascular obstruction case with enhanced cardiac magnetic resonance imaging after two days and three months. study found IMR values after PCI in patients with microvascular obstruction were significantly higher than in patients without microvascular obstruction. Yong found that in253STEMI patients after PCI, those with IMR value>40.2were associated with higher primary endpoint events (death or rehospitalization for heart failure) than those with IMR value<40.2.The clinical manifestations of coronary microcirculation dysfunction after PCI including coronary slow flow (SF) and no-reflow phenomenon (NR). The mechanisms of PCI-related coronary microcirculation dysfunction remain unclear. However, numerous studies have shown that multiple factors are involved in the mechanisms of PCI-related coronary microcirculation dysfunction.In addition, some studies also showed that endothelial dysfunction and inflammation were involved in the development of coronary microcirculation pathological process. Asymmetric dimethyl arginine (ADMA) is a new molecular marker which can reflect endothelial dysfunction, and it is an independent predictor of coronary heart disease. Recent studies indicated that endothelial dysfunction was closely related with the occurrence of complications associated with PCI. However, most of these studies focused on the prognostic value of ADMA for PCI. But ADMA is involved in the pathological process of microcirculation PCI-related adverse unclear. Numerous studies indicated that PCI significantly increased the serum hs-CRP levels in ACS patients, and the levels of serum hs-CRP were positively correlated with the complexity of coronary lesions. But the role of hs-CRP in PCI-related adverse microcirculatory perfusion is unclear.Part one. The impact of PCI on coronary microcirculation resistance in stable angina patientsObject To study the impact of elective PCI on coronary microcirculation in patients with stable angina by comparing the values of IMR before and after PCI.Method A total of35patients were enrolled in this study. They were diagnosed coronary heart disease with stable angina and subsequently undergone PCI from March2012to December2013in Affiliated Hospital of Guangdong Medical College. The preoperative biochemical, myoglobin, CK-MB, hypersensitive troponin T, and echocardiography were routine checked, and the IMR values of the left anterior descending artery before PCI were detected in all patients and retested after PCI. All patients were followed up for6months. Datas were statistically analyzed with SPSS13.0software (SPSS, Chicago, USA). Continuous variables were expressed as mean±standard deviation (x±s), and count variables were expressed as a percentage. Comparison between continuous variables were used the normal t test, when comparison various clinical indicators before and after PCI were used paired t test, and when comparison clinical indicators between diabetic and non-diabetic patients, PCI-related myocardial infarction and non-PCI-related myocardial infarction patients were used independent sample t test method; Mann-Whitney U test was used to compare between non-normally distributed continuous variables. Exploring the relationship between IMR values and other variables were used Pearson linear correlation analysis. When analyzing the correlation coefficient r, r>0.8was called highly correlated, and r<0.3was called low correlation, the other for moderate correlation. With two-tailed P<0.05was considered statistically significant.Result1. The postoperative values of IMR of left anterior descending artery were significantly increased in comparisons with the preoperative levels (P<0.05).2. The levels of postoperative values of CK-MB, myoglobin and high-sensitivity troponin T sensitive were significantly higher than the preoperative levels (P<0.01). There were five patients suffered from PCI-related myocardial infarction after PCI, and one patient arose coronary no-re flow phenomenon, and no patients died.3. The postoperative values of BNP were significantly increased compared with the preoperative levels (P<0.05). Consistently, the postoperative values of LVEF were significantly decreased compared with the preoperative levels (P<0.05).4. The values of HbAlc, postoperative high-sensitivity troponin T, preoperative CK-MB, postoperative CK-MB, preoperative myoglobin, postoperative myoglobin, postoperative BNP, preoperative BNP, preoperative and postoperative left anterior descending artery IMR in patients with PCI-related myocardial infarction were all significantly higher than those in patients without PCI-related myocardial infarction (P<0.05), whereas the value of TG, postoperative FFR, preoperative and preoperative CFR in patients with PCI-related myocardial infarction were markedly lower than those in patients without PCI-related myocardial infarction patients (P<0.05).5. The values of HbAlc, postoperative high-sensitivity troponin T, postoperative myoglobin, postoperative CK-MB and postoperative BNP in diabetics were higher than in non-diabetic patients (P<0.01). The IMR values were significantly higher in diabetics than non-diabetic patients before and after PCI (P<0.01). The changes in perioperative values of IMR changing in diabetic patients (AIMR) was greater than in non-diabetic patients (P<0.05). The changes in values of preoperative and preoperative CFR, CFR perioperative (ACFR), postoperative LVEF in diabetic patients were markedly lower than in non-diabetic patients (P<0.01).6. The preoperative and preoperative IMR values of Anterior descending artery were positively correlated with the levels of HbAlc, postoperative CK-MB, postoperative myoglobin, postoperative anterior descending artery stenosis and postoperative BNP (P<0.05), and were negatively correlated with the values of the preoperative and preoperative CFR, preoperative LVEF (P<0.05). The preoperative IMR values were highly positive correlated with postoperative IMR values in patients (P<0.05).Conclusion PCI therapy promotes coronary microcirculation resistancet The increased levels of microcirculation resistance are greater in diabetic patients after PCI than those in non-diabetic patients. The elevated level of baseline coronary microcirculation resistance is associated with increased occurrence of PCI-related myocardial infarction in patients with stable angina. Part two The impact of PCI on serum levels of asymmetric dimethyl arginine and high-sensitivity C-reactive protein in patients with stable anginaObjective To study the impact of elective PCI on coronary microcirculation endothelial function and inflammatory in stable angina patients by comparing the levels of Serum ADMA and hs-CRP before PCI and after PCI.Methods Standards for selected patients are the same as the first part of this study. All patients were phlebotomized to detect the levels of hs-CRP and ADMA in one hour before PCI and24hours after PCI. And the serum level of ADMA was detected with ELISA. The FFR, CFR and IMR values of the anterior descending artery were detected before and after PCI in all patients.Study datas were statistically analyzed with SPSS13.0software (SPSS, Chicago, USA). Continuous variables were expressed as mean±standard deviation (x±s), and count variables were expressed as a percentage. Comparison between continuous variables were used the normal t test, when comparison the values of serum ADMA and hs-CRP before and after PCI were used paired t test, and when comparison the values of serum ADMA and hs-CRP between diabetic and non-diabetic patients, PCI-related myocardial infarction and non-PCI-related myocardial infarction patients were used independent sample t test method; Mann-Whitney U test was used to compare between non-normally distributed continuous variables. Exploring the relationship between the values of serum ADMA and hs-CRP with other variables were used Pearson linear correlation analysis. When analyzing the correlation coefficient r, r>0.8was called highly correlated, and r<0.3was called low correlation, the other for moderate correlation. With two-tailed P<0.05was considered statistically significant.Result1. The postoperative levels of ADMA was significantly lower than the preoperative levels (P<0.05), whereas the postoperative levels of hs-CRP was markedly higher than the preoperative levels (P<0.05).2. The levels of preoperative ADMA were positively correlated with CH, LDL, left anterior descending artery stenosis and postoperative hs-CRP (P<0.05), and were negatively correlated with the value of preoperative and postoperative FFR (P<0.05). The levels of postoperative ADMA were positively correlated with postoperative CK-MB, postoperative myoglobin and postoperative BNP (P<0.05); and were negatively correlated with the value of postoperative FFR in patients (P<0.05).3. The levels of preoperative hs-CRP were positively correlated with the levels of HbAlc, LDL, preoperative high-sensitivity troponin T, left anterior descending artery stenosis, postoperative BNP, postoperative and preoperative IMR (P<0.05), and were negatively correlated with the values of preoperative FFR, preoperative CFR, preoperative LVEF, postoperative FFR, postoperative CFR and postoperative LVEF (P<0.05), and were highly correlation with postoperative hs-CRP (P<0.05). In addition, the levels of postoperative hs-CRP were positively correlated with HbAlc, LDL, left anterior descending artery stenosis, postoperative CK-MB, preoperative ADMA, preoperative and postoperative IMR (P<0.05), and were negatively correlated with the value of preoperative FFR, preoperative LVEF, preoperative and postoperative CFR (P<0.05).4. There were no significant difference in the levels of preoperative and postoperative serum AMDA and postoperative hs-CRP between diabetes patients and non-diabetes patients (P>0.05). The preoperative hs-CRP levels in diabetes patients were higher than those in non-diabetic patients (P<0.05).5. There were no significant difference on the levels of preoperative and postoperative ADMA and postoperative hs-CRP between patients with and without PCI-related myocardial infarction (P>0.05). The levels of postoperative ADMA in PCI-related myocardial infarction patients were higher than those in patients without PCI-related myocardial infarction (P<0.05). The preoperative hs-CRP levels in PCI-related myocardial infarction patients were higher than those in patients without PCI-related myocardial infarction patients (P<0.05).Conclusion ADMA could not be as an indicator for assessing the state of the coronary microcirculation endothelial function in patients with stable angina. The decrease of postoperative serum ADMA levels may be due to the improvement of endothelial function which benefited from the blood supply to the stenotic lesions. The elevated base line hs-CRP level is associated with the increased occurrence of PCI-related myocardial infarction in patients with stable angina during PCI. Hs-CRP could be as an indicator for assessing the state of the coronary microcirculation.