The objectives of this investigation were to evaluate biomechanical factors in the atherosclerotic process using human in vivo hemodynamic parameters and computed numerical simulation qualitatively and quantitatively. The three-dimensional spatial patterns of steady and pulsatile flows in the left coronary artery were simulated, using a finite volume method. Coronary angiogram and Doppler ultrasound measurement of the proximal left coronary flow velocity were performed in humans. Inlet wave velocity distribution obtained from in vivo data of the intravascular Doppler study allowed for input of in vitro numerical simulation. Hemodynamic variables, such as flow velocity, pressure and shear stress of the left anterior descending coronary bifurcation site were calculated. We found that there were spatial fluctuation of flow-velocity and recirculation areas at the curved outer wall of the left anterior descending coronary artery, which were due to the differences of flow-velocity and shear stress, especially during the declaration phase of pulsatile flow. This study suggests that rheologic properties may be a part of the atherogenic process in the coronary bifurcated and curved areas.
Biomechanics ; Blood Flow Velocity/physiology ; Blood Pressure/physiology ; Coronary Arteriosclerosis/physiopathology* ; Coronary Arteriosclerosis/etiology* ; Coronary Vessels/physiopathology* ; Hemodynamics/physiology* ; Homeostasis/physiology ; Human ; Models, Cardiovascular* ; Pulsatile Flow ; Stress, Mechanical

The authors investigated the relationship between anger and the calcification of the coronary artery in individuals with and without risk factors for coronary artery disease in Korea. Sixty-one subjects with risk factors of coronary artery disease and 31 subjects without risk factors were enrolled in this study. Electron Beam Computed Tomography was used to measure the calcium level of coronary artery. The anger expression scale was used to measure the anger levels. The anxiety, depression, hostility, and somatization subscales of the symptom checklist-90-revised (SCL-90-R) and the global assessment of recent stress (GARS) scale were used to assess the psychopathology and perceived stress. The logistic regression analysis results showed that only the anger-total score was significantly associated with the coronary calcification regardless of the risk factors. These results suggest that anger plays an important role in the calcification of the coronary artery.
Adult ; Aged ; *Anger ; Calcinosis/*etiology ; Coronary Arteriosclerosis/*etiology ; Female ; Human ; Lipids/blood ; Male ; Middle Aged ; Risk Factors

Lp (a) and coronary artery calcification (CAC) have recently been reported as predictors of plaque instability, but this is surrounded by much controversy. We investigated the influence of Lp (a) and CAC compared other acute coronary syndrome (ACS) risk factors. 698 patients diagnosed with at least minimal coronary artery obstructive disease from a coronary angiography were randomly selected using SPSS. Lp (a), other lipid profiles and past histories were checked, and CAC semi quantitatively graded on stored fluoroscopic images. The prevalence of CAC was significantly higher in the ACS than the non-ACS group (38.0% vs. 29.9%, p=0.026). The serum level of Lp (a) (26.89 +/- 30.64 vs. 20.85 +/- 21.63, p < 0.01) and prevalence of positive Lp (a) (> 35 mg/dl) was higher in the ACS group (24% vs. 15.7%, p < 0.01). The risk of ACS was higher in the patients with both CAC and elevated an Lp (a) than in those with only one (OR: 2.16, p=0.009, 95% CI; 1.213 - 3.843 vs. OR: 1.79, p < 0.001, 95% CI; 1.300 - 2.456). The risk of ACS was increased 1.451 times (p=0.040, 95% CI; 1.071- 2.071) in patients with CAC and 1.648 times (p=0.014, 95% CI; 1.107- 2.455) in patients with a Lp (a) > 35 mg/dl. In the younger patients (< 60 years), the Lp (a), but not the CAC, was an independent risk factor for ACS (OR=2.248, p=0.005, 95% CI; 1.281-3.943). In the older patients (> 60 years), CAC, but not the Lp (a), was an independent risk factor (OR=1.775, p=0.021, 95% CI; 1.090 - 2.890). Both the Lp (a) and CAC were risk factors for ACS, and they had a synergistic effect on its development. In the younger Lp (a), and the older CAC, was the more potent risk factor for ACS, respectively.
Acute Disease ; Age Factors ; Aged ; Aging/*blood ; Calcinosis/blood/*complications ; Coronary Arteriosclerosis/blood/*etiology ; Coronary Vessels/*pathology ; Female ; Human ; Lipoprotein (a) /*blood ; Male ; Metabolic Diseases/complications ; Middle Aged ; Risk Factors ; Support, Non-U.S. Gov't ; Syndrome

We evaluated the risk of coronary-artery disease in patients with chronic renal failure (CRF) by measuring the coronary-artery calcium scores with electron beam CT (EBCT). A total of 81 CRF patients were divided into three groups; pre-dialysis (group I, n=35), hemodialysis (group II, n=31) and peritoneal dialysis (group III, n=15). The several serum biochemical markers and calcium score levels by EBCT were determined. The Ca x P products were significantly higher in groups II (p<0.05) and III (p<0.01) than in group I. The serum calcium levels were significantly higher in group III than in both group I (p<0.01) and II (p<0.05). The serum calcium level in 15 patients with a calcium score > 400 was significantly higher than the 66 patients with a score < or =400 (p<0.01). The calcium score was significantly higher in the 15 patients with cardiovascular complications than in the 66 patients without cardiovascular complications (628.9+/-904.8 vs. 150.4+/-350.9, p<0.01). EBCT seemed to be a good diagnostic tool for evaluating the risk of coronary-artery disease ''noninvasively'' in CRF patients who are at increased risk of cardiovascular morbidity and mortality.
Adolescent ; Adult ; Aged ; Calcinosis/etiology/metabolism/*radiography ; Calcium/blood/*metabolism ; Coronary Arteriosclerosis/etiology/metabolism/radiography ; Coronary Vessels/*metabolism ; Female ; Humans ; Kidney Failure, Chronic/complications/metabolism/*radiography/therapy ; Male ; Middle Aged ; Peritoneal Dialysis ; Renal Dialysis ; Research Support, Non-U.S. Gov't ; Risk Factors ; Tomography, X-Ray Computed