Analysis Of Coronary Artery Disease With Functional Disorder

Coronary artery disease (CAD) generally including coronary atherosclerosis, functional disorder, secondry vascular dysfunction as inflammation, connective tissue diseases, etc. CAD with functional disorder refers to neither significant coronary atherosclerosis, nor secondary vascular disease, including slow coronary flow, vasospasm, and coronary syndrome X. Lots of studies concerning with coronary syndrome X, this paper focus on slow coronary flow and vasospasm.Part I Analysis of risk factors in native slow coronary flowObjective:To analyze the clinical, laboratory and angiographic characteristics of patients with slow coronary flow (SCF), and to explore its influencing factors.Method:In this retrospective study, blood velocity was calculated with the method of Thrombolysis in myocardial infarction frame count (TFC). From January2003to December2011,376SCF patients and99control patients, who performed coronary artery angiography (CAG) in our DSA room, were enrolled in the study. CAG of SCF patients showed no more than40%stenosis and delayed contrast occupation. Control subjects performed normal coronary artery and flow velocity. The clinical and laboratory data were obtained from medical records at admission, and blood velocity of each coronary artery was calculated according to TFC.Result:(1) Compared to control subjects, SCF patients were younger [(57.9±10.1) years old VS.(61.0±9.4) years old, p<0.001], more men and smokers (male:76.9%VS.42.0%, p<0.001; smokers:43.6%VS.24.0%, p<0.001). Low red blood cell distribution width (RDW) and platelet distribution width (PDW), high level of uric acid and triglyceride(TG), lower level of high density lipoprotein cholesterol (HDL-C), and apoliporotein Al(Apo-Al)[RDW(%):12.8±1.0VS.13.3±3.2, p=0.007; PDW(%):13.2±2.3VS.13.8±3.2, p=0.007; uric acid:(364±90) μmol/L VS.(327±92) μ mol/L, p<0.001; TG:(1.86±1.14) mmol/L VS.(1.64±0.91)mmol/L, p=0.007; HDL-C:(1.10±0.25) mmol/L VS.(1.22±0.36) mmol/L, p<0.001;和Apo-A1:(1.12±0.21)g/L VS.(1.29±0.26)g/L, p<0.001]. After adjustment for confounding factors in logistic analysis, the risk for developing SCF increased by gender, PDW, uric acid, TG, HDL-C, and Apo-Al [respectively ORadj=2.526(95%CI:1.592-4.008,p<0.001),0.907(95%CI:0.849-0.969, p=0.004),1.003(95%CI:1.000-1.005, p=0.018),1.326(95%CI:1.080-1.627, p=0.007),9.049(95%CI:3.092-26.486, p<0.001), and0.011(95%CI:0.003-0.041, p<0.001)]. (2) Compared within the single SCF patients, Bi-lateral SCF patients only had more men (79.8%VS.70.3%, p=0.04), but other risk factors such as age, smoking, hypertension, DM, hyperchlosterol, and stroke showed no differences. Similarly, laboratory test showed no differences, including RDW, PDW, uric acid, TG, HDL-C, Apo-Al,and LVEF.(3)Within the SCF patients, blood velocity of smokers was slower than non-smokers, respectively (frames) LAD:(80.7±33.9)VS.(71.6±26.6), p=0.004; cLAD:(47.5±20.0) VS.(42.1±15.6), p=0.004; LCX:(38.2±13.7) VS.(34.5±13.2), p=0.007; RCA:(47.1±19.1) VS.(44.0±17.5), p=0.06; mean TFC:(55.5±17.0) VS.(50.0±14.6), p=0.001; mean cTFC:(44.4±13.0) VS.(40.2±1.2), p=0.001. Similarly, velocity of male patients was slower than female patients, respectively (frames) LAD:(78.2±31.4) VS.(66.9±24.7), p=0.002; cLAD:(46.0±18.5) VS.(39.4±14.5), p=0.002; LCX:(37.9±13.6) VS.(30.2±11.3), p<0.001; RCA:(47.6±18.9) VS.(38.7±13.9), p<0.001; mean TFC:(54.6±16.2) VS.(45.3±12.5), p<0.001; mean cTFC:(43.8±12.6) VS.(36.1±9.6), p<0.001.Conclusion:Gender, PDW, TG, HDL-C, and Apo-Al were independent predictors of native SCF. Comparing Bi-SCF with S-SCF, clinical manisfaction and metabolism of lipids were no different. Within SCF patients, gender and smoking affected velocity.Part Ⅱ Immediate and long-term flow velocity of PCI target coronary artery and its clinical outcomesObjective:To explore the risk factors of SCF, improving factors of SCF, and reducing factors of normal flow velocity in PCI target vessels.Methods:From January2003to December2011,105patients, who had received PCI procedures with drug-eluting stents, were enrolled in the study. According to flow velocity of PCI and follow-up coronary artery angiography (CAG), patients were divided into four groups.33patients of Control group showed normal flow velocity of PCI and follow-up CAG.32patients of Immediate slow group showed SCF in PCI procedure and normal flow velocity in follow-up CAG.26patients of Delayed slow group showed normal flow in PCI but slow flow in follow-up CAG.14patients of Bi-slow group showed slow flow in PCI and follow-up CAG. Compare its differences of basic clinical characteristics, laboratory tests, PCI operation process and chronic drug use. Major adverse cardiac events (MACE) were followed up, including cardiac death, re-infarction, target lesion revascularization, target vessel revascularization and In Stent Restenosis.Results:93(88.6%) of all105patients are men, and average age were63.0±10.9years old.3～20(10.6±6.8) months later, follow-up CAG were performed. MACE were followed up since the follow-up CAG, and the average follow-up time was46±30(10-110) months.(1) After adjustment for confounding factors in logistic analysis, the risk for developing SCF increased by primary PCI (ORadj=3.734,95%CI:1.058-13.178, p=0.041). During follow-up, MACE occurred in8patients (17.4%) of SCF group, and in5patients (8.5%) of Non-SCF group. Kaplan-Meier survival analysis showed no difference between the incidences of MACE (p=0.43).(2)Among the SCF patients, diabetes mellitus (DM), red blood cell distribution width (RDW), and angiotensin converting enzyme inhibitors (ACEI)/angiotension II receptor blocker (ARB) were the independent predictors of flow improvement in the follow up. After adjustment for confounding factors in logistic analysis, the risk for long-term SCF improved by DM (ORadj=0.032,95%CI:0.002-0.429, p=0.009), RDW (ORadj=0.216,95%CI:0.048-0.983, p=0.047), and ACEI/ARB (ORadj=65.120,95%CI:2.851-1487.271, p=0.009). During follow-up, MACE occurred in6patients (18.8%) of Immediate slow group, and in2patients (14.3%) of Bi-slow group. Kaplan-Meier survival analysis showed no difference between the incidences of MACE (p=0.60).(3) After adjustment for confounding factors in logistic analysis, the risk for developing slow flow in Non-SCF group increased by age (ORadj=0.892,95%CI:0.808-0.983, p=0.022), pressure of pre-dilation balloon (ORadj=0.564,95%CI:0.361-0.882, p=0.012), and diameter of pre-dilation balloon (ORadj=323.312,95%CI:3.028-34525.364,p=0.015).During follow-up, MACE occurred in4patients (12.1%) of Control group, and in1patient (3.8%) of Delayed group. Kaplan-Meier survival analysis showed no difference between the incidences of MACE (p=0.12).Conclusions:Primary PCI was the risk factor of SCF. During follow-up, flow velocity of SCF patients was affected by DM, RDW, and ACEI/ARB; flow velocity of Non-SCF patients was affected by age, pressure and diameter of pre-dilation balloon. But incidence of MACE wasn’t affected by SCF. Long-term flow velocity outcome of PCI immediate flow didn’t affect clinical outcome.Part III Clinical characteristics of CSA and its relationship with fixed stenosis Objective:Coronay spasm is an important mechanism of heart attack, which belongs to coronary artery functional disorder. To investigate the clinical features of coronary spastic angina(CSA) with associated syncope, early identification of fixed stenosis by comparing differences of the risk factors, clinical manifestations and laboratory examinations, and to evaluate the clinical outcomes of CSA patients with severe organic stenosis treated with drug-eluting stents.Methods:Between2003and2011, CSA with typical symptom and electrocardiogram was diagnosed in74patients admitted to our cardiovascular department.16patients had a history of syncope during cardiac attacks while the remaining58had none. Cardiovascular risk factors, clinical characteristics and coronary angiographic findings were compared between the two groups. Patients were divided into non-stenosis group (stenosis<50%, n=45) and stenosis group(stenosis≥50%, n=29) according to the degree of stenosis. The differences of the risk factors, clinical manifestations and laboratory examinations between these two groups were compared. Of these, drug-eluting stents were implanted in coronary segments with severe organic stenosis (diameter stenosis more than70%) for7patients. Coronary angiography were performed6to18months after percutaneous coronary intervention and the patients were clinically followed up for17to50months.Results:Of all74CSA patients,65(87.8%) male patients and48(64.9%) smokers, the average age was (53.5±8.7) years old.(1) Serious arrhythmias were recorded more often in syncope group (100%) than non-syncope group (10.3%, p<0.0001). Low-density lipoprotein cholesterol was lower in syncope group [(1.68±0.45)mmol/L] than non-syncope group[(2.15±0.73) mmol/L, p=0.003]. There were no differences in cardiovascular risk factors, pain duration, medication, left ventricular ejection fraction, the location and extent of ST-segment elevation in12-lead electrocardiogram. Compared with the non-syncope group, syncope group had a lower incidence of left anterior descending artery (LAD) stenosis (34.48%VS6.25%, p=0.03)and a non-significant higher incidence of right coronary artery (RCA) stenosis (8.62%VS25%, p=0.095) in coronary angiography. In multivariable Logistic analysis, serious arrhythmias (p<0.0001) and RCA stenosis (p=0.028) were independently related to syncope.(2) The average age of patients in stenosis group [(57.5±8.4) years old] was higher than that in non-stenosis group [(52.3±9.1) years. p=0.02]. Other traditional risk factors of coronary atherosclerosis, such as male, smoking, hypertension, diabetes mellitus, lipid disorder did not show any differences between the two groups. Percentage of patients with angina pectoris lasting less than5minutes was higher in stenosis group (p=0.02), while percentage of effort angina, quickly seeing a doctor and hymody-namic disorder showed no differences. Laboratory examinations had no differences.(3)Nine drug-eluting stents with2.75-3.5(3.08±0.24)mm in diameter and24-33(27.3±3.6)mm in length were successfully implanted in these7patients. Stents were implanted in left anterior descending artery (LAD) in5patients (71.4%), right coronary artery (RCA) in1patient(14.3%), both LAD and RCA in1patient (14.3%). Transient RCA spasm and distal LAD spasm was observed during percutaneous coronary intervention of LAD in2patients, respectively. Anginal attack at rest with transient ST segment elevation at VI-3leads occurred24hours after stenting in LAD in1patient. Follow-up coronary angiography showed significant in-stent restenosis or focal edge restenois (diameter stenosis more than50%) in3patients (42.9%), mild neointimal proliferation and no restenosis in2patients (28.6%), and no neointimal proliferation in2patients (28.6%). During clinical follow-up,2patients (28.6%) remained asymptomatic, while the remaining5patients (71.4%) presented as effort angina and/or rest angina.Conclusions:Syncope is a common complication in patients with CSA, and serious arrhythmias are the direct trigger factor. Fixed stenosis in RCA is susceptible to syncope, and a more active intervention should be advisable for those patients.It is hard to determine whether the CSA patient has fixed coronary stenosis by analyzing the risk factors, clinical manifestations and laboratory examinations, which necessitates coronary angiography to determine fixed coronary stenosis. The high incidence of restenosis and recurrent chest pain may overshadow the application of stenting for severe organic stenosis in CSA patients.