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PubMed1992

Target lesion calcification in coronary artery disease: an intravascular ultrasound study.

OBJECTIVES: The purpose of this study was to evaluate the frequency, amount and distribution of target lesion calcification in patients undergoing transcatheter therapy for symptomatic coronary artery disease. BACKGROUND: Coronary artery target lesion calcification may be an important determinant of response to transcatheter therapy: balloon angioplasty causes dissections in calcified lesions, directional atherectomy cuts calcium poorly, rotational atherectomy causes preferential ablation of calcium and laser irradiation effect may vary. Intravascular ultrasound imaging is a highly sensitive technique for detection of plaque calcification in vivo. METHODS: We performed intravascular ultrasound imaging before or after, or both, various transcatheter therapies in 110 patients. These 84 men and 26 women had a mean age of 60 years and a duration of angina of 22 +/- 34 months. Forty-nine patients had one-vessel, 29 had two-vessel, 25 had three-vessel and 7 had left main coronary disease. Vessels treated and imaged were the left main (n = 7), left anterior descending (n = 47), left circumflex (n = 18) and right (n = 38) coronary arteries. RESULTS: Eighty-four patients (76%) had target lesion calcification; 29 patients had one-quadrant, 25 had two-quadrant, 17 had three-quadrant and 13 had four-quadrant calcification. The calcification was superficial in 42 patients, deep in 13 and both superficial and deep in 31. The axial length of calcium could be measured in 29 patients; it was < or = 5 mm in 11 and > or = 6 mm in 18. Fluoroscopy detected calcification in 50 patients (48%, p < 0.001 vs. detection by ultrasound); this proportion increased to 74% in patients with calcification of two or more quadrants and to 86% in patients with calcification > or = 6 mm in length of two or more quadrants. Calcification was more common in patients who smoked and tended to be more common in patients with multivessel disease or previous coronary artery bypass graft surgery. CONCLUSIONS: We conclude that target lesion calcification occurs in 75% of patients with symptomatic coronary artery disease requiring angioplasty. Target lesion calcification is best detected, localized and quantified by intravascular ultrasound. These observations may be important in selecting devices for transcatheter therapy.

Adult↗
PubMed2004

Spiral computed tomography evidence of close correlation between coronary and thoracic aorta calcifications.

UNLABELLED: Coronary calcium (CC) is invariably associated with coronary atherosclerosis and can be diagnosed noninvasively by fast spiral computed tomography (dual slice mode) (CT). Calcium is often deposited in the aorta as well, but the pathogenesis, correlates and clinical implications of calcification of the aorta are not yet elucidated. A possible association between the presence of CC and thoracic aorta calcification, as detected by spiral CT, has not been investigated yet. The goal of the present work was to examine by spiral CT whether an association exists between the presence of CC and thoracic aorta calcification in patients with high risk for atherosclerotic development. Four hundred and five patients with at least two risk factors for atherosclerosis were included (212 men and 193 women, age ranged 52-79 years). All underwent chest CT for CC and aortic calcification scoring. Calcifications' thickness of > or =5 mm was considered advanced. CC was documented in 294 patients (170 men, 124 women; mean age 66 +/- 6 years, range 55-78 years). The non-CC group (control) included 111 patients (42 men, 69 women; mean age 64 +/- 6 years, range 52-79 years). Significant differences were found between CC group and control for the presence of ascending aorta calcification (69% versus 36%, P < 0.001), and advanced calcification of > or =5mm (17% versus 4%, P < 0.001). Significant differences were also found between groups regarding the presence of descending aorta calcification (60% versus 38%, P < 0.001), and number of consecutive slices with calcification (18.8 +/- 12.4 versus 10.7 +/- 8.7, P < 0.01). We identified age (in decades) (OR 1.9, 95% CI 1. 2-3.0, P < 0.001), gender (female) (OR 0.4, 95% CI 0.2-0.6, P < 0.001), and thoracic aorta calcification (OR 2.9, 95% CI 1.7-5.0, P < 0.001) as the independent variables significantly associated with CC. Only age [odds ratio (OR) 3.05, 95% confidence interval (CI) 1.86-5.01, P < 0.001] and CC (OR 2.53, 95% CI 1.26-5.08, P = 0.006) were identified as independent variables for the prediction of thoracic aorta calcification. CONCLUSIONS: Our study demonstrated a strong association of CC and calcification of the thoracic aorta on spiral CT.

Aged↗
PubMed1998

In vitro testing of bioprostheses: influence of mechanical stresses and lipids on calcification.

BACKGROUND: Structural valve deterioration of bioprostheses is mainly caused by the progressive development of calcification. Mechanical stresses or lipid deposits in porcine aortic leaflets have been proposed as major factors contributing to the calcification process. METHODS: A new test protocol consisting of nondestructive holographic interferometry, which allows a quantitative deformation analysis of heart valves, and accelerated dynamic in vitro calcification was used. The rapid calcification fluid contained a final combined calcium and phosphorus concentration of 130 (mg/dL)2 in barbital buffer solution. The calcification of 32 bioprostheses donated by different manufacturers (SJM Bioimplant, Biocor standard, Biocor No-React, Carpentier-Edwards SAV, Bravo, pericardial prototype) was assessed after up to 25 x 10(6) cycles by microradiography and the areas of calcification were compared with the holographic interferograms. The distribution of lipid droplets of four porcine prostheses were visualized by Sudan III stain before the calcification process. RESULTS: Most of the tested bioprostheses had areas presenting with stress concentrations, and the dynamic in vitro testing resulted in leaflet calcification corresponding to the holographic irregularities. A strong correlation between calcification and stress distribution or lipid accumulation was found (r = 0.72; r = 0.81, respectively). After 19 x 10(6) cycles, the Carpentier-Edwards SAV and the pericardial valves had significantly less calcification than other prostheses tested (p = 0.003), but the variation among individual prostheses from the same manufacturer was even more pronounced. CONCLUSIONS: Mechanical stresses or lipid accumulation seems to play an important role in the calcification process of bioprostheses. Quality control of bioprosthetic valves using holographic interferometry has the potential to predict calcification before implantation.

Aortic Valve↗
PubMed2002

Mechanisms of calcification by vesicles isolated from atherosclerotic rabbit aortas.

Although several lines of evidence support the role of calcifiable vesicles in dystrophic vascular calcification, the mechanisms whereby vesicles promote aortic calcification remain incompletely understood. Previous reports indicate that ATP promotes in vitro vesicle calcification. Whether ATP-initiated calcification is simply mediated through increased Pi concentrations or by other unknown mechanisms related to ATP hydrolysis is unclear. To determine whether high Pi levels resulting from ATP hydrolysis may cause CaxP ion products to surpass the threshold for calcium phosphate precipitation, 3 mM Pi instead of 1 mM ATP was added to calcifying media. The inclusion of 1 mM ATP in calcifying media with an initial serum level of Ca2+ (1.45 mM) and Pi (2.3 mM) was much more effective in promoting calcification than the addition of 3 mM Pi. The higher effectiveness of ATP over Pi in promoting calcification was consistent throughout various incubation periods and vesicle protein ranges. To minimize the effect of CaxPi ion products on calcification, the ion product was kept within the physiological ranges throughout the incubation period by reducing initial Pi or ATP concentrations in calcifying media. At these low levels of ion products, ATP was still more effective than Pi in promoting calcification. Both ATP- and Pi-stimulated calcifications were found to increase with increasing levels of ion products whereas greater effectiveness of ATP over Pi remained unaltered. These observations indicate that ATP hydrolysis may initiate calcification through some mechanisms other than a simple provision of Pi in order to surpass the solubility products. Concanavalin A (Con A) was found to bind to vesicles and to enhance both ATP- and Pi-promoted calcification. Taken together, these observations suggest that ATP hydrolysis, CaxP ion products, and vesicle-associated carbohydrates are implicated in vesicle-mediated calcification.

Adenosine Triphosphate↗
PubMed2002

Cardiac calcification in adult hemodialysis patients. A link between end-stage renal disease and cardiovascular disease?

OBJECTIVES: We sought to determine clinical and laboratory correlates of calcification of the coronary arteries (CAs), aorta and mitral and aortic valves in adult subjects with end-stage renal disease (ESRD) receiving hemodialysis. BACKGROUND: Vascular calcification is known to be a risk factor for ischemic heart disease in non-uremic individuals. Patients with ESRD experience accelerated vascular calcification, due at least in part to dysregulation of mineral metabolism. Clinical correlates of the extent of calcification in ESRD have not been identified. Moreover, the clinical relevance of calcification as measured by electron-beam tomography (EBT) has not been determined in the ESRD population. METHODS: We conducted a cross-sectional analysis of 205 maintenance hemodialysis patients who received baseline EBT for evaluation of vascular and valvular calcification. We compared subjects with and without clinical evidence of atherosclerotic vascular disease and determined correlates of the extent of vascular and valvular calcification using multivariable linear regression and proportional odds logistic regression analyses. RESULTS: The median coronary artery calcium score was 595 (interquartile range, 76 to 1,600), values consistent with a high risk of obstructive coronary artery disease in the general population. The CA calcium scores were directly related to the prevalence of myocardial infarction (p < 0.0001) and angina (p < 0.0001), and the aortic calcium scores were directly related to the prevalence of claudication (p = 0.001) and aortic aneurysm (p = 0.02). The extent of coronary calcification was more pronounced with older age, male gender, white race, diabetes, longer dialysis vintage and higher serum concentrations of calcium and phosphorus. Total cholesterol (and high-density lipoprotein and low-density lipoprotein subfractions), triglycerides, hemoglobin and albumin were not significantly related to the extent of CA calcification. Only dialysis vintage was significantly associated with the prevalence of valvular calcification. CONCLUSIONS: Coronary artery calcification is common, severe and significantly associated with ischemic cardiovascular disease in adult ESRD patients. The dysregulation of mineral metabolism in ESRD may influence vascular calcification risk.

Adult↗
PubMed2003

Increased prevalence of coronary artery calcification in patients with suspected pulmonary embolism.

RATIONALE AND OBJECTIVES: The authors explored the possibility that patients with suspected pulmonary embolism are at high risk for coronary artery disease. To this purpose, they compared the presence of coronary artery calcification on computed tomography (CT) in patients suspected of pulmonary embolism with age- and gender-matched controls. MATERIALS AND METHODS: The CT scans of 214 patients were reviewed. Of those, 107 consecutive patients (50%) had pulmonary CT angiography for suspected pulmonary embolism (PE group). The remaining 107 age- and gender-matched patients were scanned for reasons other than pulmonary embolism (non-PE group). All CT scans were performed with the same 8-detector-row multislice scanner. Two radiologists reviewed scans of 5-mm slices using a five-grade modified coronary calcium scoring system: 1 = no calcification; 2 = minimal calcification; 3 = mild calcification; 4 = moderate calcification; and 5 = severe calcification. The Marginal Homogeneity test was used to compare the distribution and severity of calcification in the two groups. RESULTS: Of 107 patients in the PE group, seven (6.54%) had pulmonary embolism detected on CT. Coronary artery calcification was detected in 61 patients (57%) in the PE group compared with 42 patients (39%) in the non-PE group. The Marginal Homogeneity test showed that patients with pulmonary embolism symptoms were 2.9 times more likely to have calcification detected compared with those patients who had chest CT for some other reason (P = .0034). However, in patients in whom coronary artery calcification was detected, the distribution of severity of calcification was the same in both groups. CONCLUSION: Assuming coronary artery calcification indicated coronary atherosclerosis, patients undergoing CT for suspected pulmonary embolism may be at high risk for coronary artery disease.

Adolescent↗
PubMed2004

Calcifying obstructive pancreatitis: a study of intraductal papillary mucinous neoplasm associated with pancreatic calcification.

BACKGROUND AND AIMS: We have observed intraductal papillary mucinous neoplasm (IPMN) associated with pancreatic calcification. The aim of this study is to describe the profile of IPMN associated with calcification and gain insights into the pathogenesis of calcification in IPMN. METHODS: We identified 10 patients with IPMN with pancreatic calcification, of whom 7 underwent pancreatic resection. We reviewed demographic data, history of previous pancreatitis, and radiological and histological features of these patients. RESULTS: In patients with IPMN with calcification (mean age, 65 +/- 12 yr; 50% men), a diagnosis of chronic calcifying pancreatitis was entertained in 5 of 10 patients; 2 patients had undergone previous endoscopic therapy for stone removal. There was no previous history of pancreatitis in 9 of 10 patients. Radiologically, calcifications were seen diffusely throughout the gland in 8 of 10 patients and interpreted as chronic calcific pancreatitis. Although 1 of the 7 patients who underwent resection had diffuse IPMN throughout the gland, 6 patients had IPMN confined to the head or uncinate process (mean size, 2.75 cm; range, 1.1-5 cm). Histologically, 6 of 7 IPMNs were adenomas, and 1 patient had invasive cancer. No patient had intratumoral calcification. All 7 patients had calcification within the main pancreatic duct and/or side branches, often within inspissated mucus. CONCLUSIONS: IPMN associated with pancreatic calcification can lead to misdiagnosis and inappropriate treatment for chronic calcifying pancreatitis. In the absence of intratumoral calcification or a previous history of long-standing chronic pancreatitis, calcification in IPMN likely represents a unique and hitherto unrecognized form of calcifying obstructive pancreatitis caused by prolonged partial obstruction of the pancreatic duct.

Adenocarcinoma, Mucinous↗
PubMed2005

Evaluation of aortic arch calcification in type 2 diabetic patients.

BACKGROUND: The purpose of this study is to evaluate the severity of aortic arch calcification among type 2 diabetic patients in association with diabetes duration, diabetic complications, coronary artery disease and presence of cardiovascular risk factors. PATIENTS AND METHODS: This study included 207 type 2 diabetic patients (101 men) with a mean age of 61.5 +/- 8.1 years and a mean diabetes duration of 13.9 +/- 6.4 years. Aortic arch calcification was assessed by means of posteroanterior chest X-rays. Severity of calcification was graded as follows: grade 0 (no visible calcification), grade 1 (small spots of calcification or single thin calcification of the aortic knob), grade 2 (one or more areas of thick calcification), grade 3 (circular calcification of the aortic knob). RESULTS: Severity of calcification was grade 0 in 84 patients (40.58%), grade 1 in 64 patients (30.92%), grade 2 in 43 patients (20.77%) and grade 3 in 16 patients (7.73%). In simple regression analysis severity of aortic arch calcification was associated with age (p = 0.032), duration of diabetes (p = 0.026), insulin dependence (p = 0.042) and presence of coronary artery disease (p = 0.039), hypertension (p = 0.019), dyslipidaemia (p = 0.029), retinopathy (p = 0.012) and microalbuminuria (p = 0.01). In multiple regression analysis severity of aortic arch calcification was associated with age (p = 0.04), duration of diabetes (p = 0.032) and presence of hypertension (p = 0.024), dyslipidaemia (p = 0.031) and coronary artery disease (p = 0.04), while the association with retinopathy, microalbuminuria and insulin dependence was no longer significant. CONCLUSIONS: Severity of aortic arch calcification is associated with age, diabetes duration, diabetic complications (retinopath), microalbuminuria), coronary artery disease, insulin dependence, and presence of hypertension and dyslipidaemia.

Aortic Arch Syndromes↗
PubMed2006

Increased breast calcifications in women with ESRD on dialysis: implications for breast cancer screening.

BACKGROUND: Different appearances of breast calcification on mammography can differentiate benign from malignant disease. An increased incidence of breast calcifications in dialysis patients is established, but data for morphological characteristics in renal patients, incidence of benign and malignant calcifications, and clinical consequences are limited. In this study, we compare mammograms and the workup of abnormal calcifications of women on hemodialysis with that of women with normal renal function. METHODS: This is a retrospective case-control study; 45 women on hemodialysis had their screening mammograms reviewed. A control group of 86 age-matched women with normal renal function was randomly obtained for comparison. Mammograms were examined and the recommended workup was traced. Breast calcification morphological characteristics, incidence of benign versus malignant calcifications, callback rate, and biopsy recommendation rates were compared to determine whether breast calcifications in renal patients led to excessive workups. RESULTS: Overall, breast calcifications in the renal group were statistically significantly increased compared with controls, mostly because of several benign-appearing morphological characteristics. No statistically significant difference was present between the 2 groups with respect to callback rates. However, incidences of malignancy-associated calcification and hence biopsy recommendation rate were slightly greater for the renal group. CONCLUSION: Renal patients have an increase in breast calcification, mostly caused by several benign calcifications. The callback rate is no greater than that in the general population. However, there is a slightly greater incidence of malignancy-associated calcifications; hence, once called back, they have a greater probability of being recommended for biopsy.

Adult↗
PubMed2000

Coronary-artery calcification in young adults with end-stage renal disease who are undergoing dialysis.

BACKGROUND: Cardiovascular disease is common in older adults with end-stage renal disease who are undergoing regular dialysis, but little is known about the prevalence and extent of cardiovascular disease in children and young adults with end-stage renal disease. METHODS: We used electron-beam computed tomography (CT) to screen for coronary-artery calcification in 39 young patients with end-stage renal disease who were undergoing dialysis (mean [+/-SD] age, 19+/-7 years; range, 7 to 30) and 60 normal subjects 20 to 30 years of age. In those with evidence of calcification on CT scanning, we determined its extent. The results were correlated with the patients' clinical characteristics, serum calcium and phosphorus concentrations, and other biochemical variables. RESULTS: None of the 23 patients who were younger than 20 years of age had evidence of coronary-artery calcification, but it was present in 14 of the 16 patients who were 20 to 30 years old. Among those with calcification, the mean calcification score was 1157+/-1996, and the median score was 297. By contrast, only 3 of the 60 normal subjects had calcification. As compared with the patients without coronary-artery calcification, those with calcification were older (26+/-3 vs. 15+/-5 years, P<0.001) and had been undergoing dialysis for a longer period (14+/-5 vs. 4+/-4 years, P< 0.001). The mean serum phosphorus concentration, the mean calcium-phosphorus ion product in serum, and the daily intake of calcium were higher among the patients with coronary-artery calcification. Among 10 patients with calcification who underwent follow-up CT scanning, the calcification score nearly doubled (from 125+/-104 to 249+/-216, P=0.02) over a mean period of 20+/-3 months. CONCLUSIONS: Coronary-artery calcification is common and progressive in young adults with end-stage renal disease who are undergoing dialysis.

Adolescent↗
PubMed2005

Vascular calcification and cardiovascular function in chronic kidney disease.

BACKGROUND: Vascular calcification and arterial stiffening are independent predictors of all causes and cardiovascular mortality in chronic kidney disease (CKD). Few data are currently available comparing vascular calcification and its attendant functional cardiovascular consequences between CKD stage 4 patients and both peritoneal dialysis (PD) and haemodialysis (HD) (CKD stage 5) patients. METHOD: We studied 134 subjects (60 HD, 28 PD and 46 CKD 4). Vascular calcification was quantified using multi-slice spiral CT scanning of a 5 cm standardized segment of superficial femoral artery. Pulse wave analysis and pulse wave velocity were assessed using applanation tonometry, to determine arterial compliance. Further digital arterial pulse wave analysis was used to measure systemic haemodynamic variables. All medications were recorded and biochemical variables were time averaged for the 6 months prior to entering the study. RESULTS: Forty-seven percent of CKD 4 patients demonstrated vascular calcification as compared with CKD 5 (71% PD and 73% HD, P = 0.02). HD patients had higher calcification scores (median 121) than either PD (median 21) or CKD 4 (median 0) (P = 0.008). There were no significant differences in baseline characteristics between the groups. Comparing tertiles of patients (based on calcification score), increased calcification score was associated with a reduction in arterial compliance (mean PWV 8.9 +/- 1.1, 11 +/- 3.6, 11.3 +/- 3.7 m/s, P = 0.005). The degree of calcification did not influence systolic blood pressure (BP), diastolic BP or heart rate. However, more heavily calcified patients demonstrated significantly higher mean pulse pressures (58 +/- 19, 74 +/- 22 and 72 +/- 25 mmHg, P = 0.001), lower total peripheral resistance (1.5 +/- 1, 1.3 +/- 0.8, 0.9 +/- 0.4, P = 0.01) and higher stroke volume (84 +/- 25, 95 +/- 29, 106 +/- 39 ml, P = 0.01). More heavily calcified patients were significantly older and predominantly male. CONCLUSION: This study has successfully utilized a novel technique for the quantification of calcification. We have demonstrated vascular calcification and associated cardiovascular dysfunction in CKD 4, PD and HD with significant differences between the groups. Thirty percent of individuals show no calcification, even those established on renal replacement therapy for a prolonged period of time. Further work is required to identify factors which promote progression of arterial calcification in those who are susceptible.

Calcinosis↗
PubMedDate not supplied

Appearance and distinguishing features of retroperitoneal calcifications at computed tomography.

OBJECTIVES: To describe the appearance of retroperitoneal calcifications seen at computed tomography (CT) and to investigate which CT features distinguish benign from malignant retroperitoneal calcifications. METHODS: We identified 25 patients with retroperitoneal calcifications by retrospective review of 39,931 abdominopelvic CT scans. Etiology of retroperitoneal calcifications was determined by examination of medical and histopathological records. By consensus, 2 abdominal radiologists recorded calcification number (solitary or multiple), location (suprarenal or infrarenal), morphology (globular or nonglobular), and the presence of soft-tissue components. The association between CT findings and etiology was assessed using the Fisher exact test. RESULTS: Retroperitoneal calcifications were malignant in 15 patients and benign in 10. Solitary calcifications were seen more commonly in patients with benign disease (6 of 10 vs. 1 of 15, P < 0.01). Suprarenal calcifications were seen only in patients with malignancy (13 of 15 patients, P < 0.01). Nonglobular calcifications were seen only in patients with benign disease (6 of 10, P < 0.01). Soft-tissue components were seen more commonly in patients with malignancy (14 of 15 vs. 4 of 10; P < 0.01). CONCLUSIONS: Retroperitoneal calcifications are rarely seen at CT and may be benign or malignant in etiology. Solitary or nonglobular retroperitoneal calcifications are likely to be benign while calcifications that are multiple, globular, suprarenal, or associated with noncalcified soft-tissue components are likely to be malignant.

Adult↗
PubMed2001

Calcification properties of saline-filled breast implants.

Three patients requested explantation of their saline-filled breast implants. Bilateral calcification had occurred in all six implants. Four of the implants were manufactured by McGhan Corporation (Santa Barbara, Calif.), and two, by the Simaplast Company (Toulon, France). All implants had been inserted in the subglandular plane and had been in place for 7 to 23 years. At the time of explantation, patients were 32, 34, and 44 years old. Calcification on the surface of the implants and capsules was analyzed. Implant surface calcification was clinically evident on all six implants, appearing as ivory-colored, tenaciously adherent deposits, only on the anterior surface of the implant. Capsular calcification, which was observed only microscopically, was characterized by poorly organized, irregularly shaped, calcified agglomerates; this calcification also occurred only on the anterior surface of the capsule, adjacent to the area of calcification on the implant. Ultrastructural analysis of scrapings from the implant surface showed large, electron-dense aggregates of crystals, with individual crystals measuring approximately 40 x 10 x 10 nm. In contrast, capsular calcification was characterized by two patterns of deposition, spherulitic aggregates of needle-shaped crystals and areas of metaplastic bone. The individual crystals were approximately 40 x 10 x 10 nm. Energy-dispersive x-ray spectroscopy of specimens from the areas of calcification on the implant and capsule surfaces demonstrated calcium and phosphorus. Electron diffraction of crystals from the implant and capsule surfaces demonstrated the D-spacings characteristic of calcium apatite. There were many differences between the calcification properties of these six saline implants and those of silicone gel implants. For example, mineralization has not been observed on the surface of gel implants, but in these saline implants it occurred primarily on the implant surface. Also, capsular calcification has been observed clinically in gel implants across the surface of the capsule (except at the site of attachment of a Dacron patch), but in this study it was observed only microscopically and was located on the anterior surface of the capsule, adjacent to the area of calcification on the implant. In addition, crystals 100 times larger than those observed on the six saline implant capsules have been observed on the surface of gel implant capsules. A model is presented to explain the mechanism of calcification associated with breast implants and to explain the observed differences between saline-filled and gel-filled implants.

Adult↗
PubMed2005

Aortic valve calcification: association with bone mineral density and cardiovascular risk factors.

BACKGROUND: Cardiovascular risk factors are reported to increase the incidence of aortic valve calcification. Among older women, low bone mineral density appears to be associated with increased prevalence of aortic calcification. We aimed to assess and compare cardiovascular risk factors and bone mineral density of patients with and without aortic valve calcification. MATERIALS AND METHODS: Cardiovascular risk factors and bone mineral density measurements have been assessed in 49 patients with aortic valve calcification and in 65 patients without aortic valve calcification. All patients were subsequently referred to the nuclear medicine department to measure bone mineral density after echocardiographic evaluation. RESULTS: No statistically significant differences were observed between the two groups with respect to sex, body mass index, history of coronary artery disease, diabetes mellitus, hypercholesterolemia, and smoking status. Although height and weight of the patients with aortic valve calcification were significantly lower than those of patients without aortic valve calcification, they were not independent risk factors. Age and hypertension were found to be independent positive risk factors for aortic valve calcification, whereas T score was found to be negatively associated with aortic valve calcification. CONCLUSION: We have shown that aortic valve calcification is positively associated with age and hypertension, whereas bone mineral density is negatively associated with aortic valve calcification. The mechanism underlying the association between decreased bone mineral density and aortic valve calcification remains to be clarified in further studies.

Aged↗
PubMedDate not supplied

Abnormal calcifications in the urinary tract.

A wide variety of calcifications may develop in the urinary tract. Calculi, the most common form of urinary tract calcification, are usually radiopaque due to their calcium content, whereas cystine stones tend to be less opaque. In cortical nephrocalcinosis, calcification may be spotty or may appear as a thin rim outlining the cortex. Intracystic calcification is usually thin and peripheral and is often described as having an "eggshell" appearance. In renal masses, pure central calcification usually indicates malignancy, although malignancy may also be present with pure peripheral calcification. An incomplete ring of calcification seen over the central portion of the kidney should suggest the presence of an abnormal vascular structure. A sloughed papilla may lead to calcification that is usually triangular or ring-shaped or has a broken rim pattern. Ureteral calculi usually have a uniform radiopacity, whereas phleboliths are often less opaque centrally. Like renal calculi, bladder calculi usually contain a calcium component; they may be laminated, faceted, spiculated, or seedlike in appearance. Urachal carcinoma is commonly associated with tumor calcification, which typically occurs at the dome of the bladder. Schistosomiasis of the bladder may produce mural calcification with a typical thin arcuate pattern and may be associated with calcification in other portions of the urinary tract. Although urinary tract calcifications may be difficult to characterize specifically, they can be classified according to location, appearance, and relation to various pathologic conditions.

Calcinosis↗
PubMed2006

Prevalence and clinical importance of aortic valve calcification detected incidentally on CT scans: comparison with echocardiography.

PURPOSE: To evaluate retrospectively the prevalence and grade of aortic valve calcification incidentally detected on chest multi-detector row computed tomographic (CT) scans and to compare the grade of calcification with the severity of aortic valve disease as assessed with echocardiography. MATERIALS AND METHODS: Patient informed consent was waived by the institutional board on medical ethics that approved this study. The authors identified 402 patients (231 men and 171 women; mean age, 62.5 years +/- 12.1) of 1820 patients who underwent chest multi-detector row CT between July 2001 and August 2004 and also underwent echocardiography. Aortic valve calcification at multi-detector row CT was visually graded on a scale ranging from 0 to 4 (0 = no calcification, 4 = severe calcification). CT findings were correlated with hemodynamic data obtained at echocardiography. Patients without aortic stenosis were compared with patients with aortic stenosis. The Student t test, Spearman correlation coefficient, chi(2) analysis, and an unweighted kappa test were used to compare results. RESULTS: Aortic valve calcification was noted on multi-detector row CT scans in 72 of the 402 patients (18%). Twelve of 20 patients (60%) with grade 3 or grade 4 calcification on CT scans had aortic stenosis at echocardiography, compared with only nine of 382 patients (2.4%) with grade 0-2 calcification (P < .001). Significant correlations were observed between the grade of aortic valve calcification and the echocardiographically determined mean (r = 0.45, P = .03) and peak transvalvular gradient (r = 0.47, P = .03). There was substantial agreement between the grade of valve calcification at multi-detector row CT and the severity of aortic valve disease at echocardiography (kappa = 0.67). CONCLUSION: Aortic valve calcification was an incidental finding on 18% of multi-detector row CT scans. The grade of aortic valve calcification is correlated with the hemodynamic severity of aortic valve disease as determined with echocardiography.

Aortic Valve↗
PubMed2006

Calcification of human vascular smooth muscle cells: associations with osteoprotegerin expression and acceleration by high-dose insulin.

Arterial medial calcifications occur often in diabetic individuals as part of the diabetic macroangiopathy. The pathogenesis is unknown, but the presence of calcifications predicts risk of cardiovascular events. We examined the effects of insulin on calcifying smooth muscle cells in vitro and measured the expression of the bone-related molecule osteoprotegerin (OPG). Human vascular smooth muscle cells (VSMCs) were grown from aorta from kidney donors. Induction of calcification was performed with beta-glycerophosphate. The influence of insulin (200 microU/ml or 1,000 microU/ml) on calcification was judged by measuring calcium content in the cell layer and by von Kossa staining. OPG was measured in the medium by ELISA. Histochemistry was used for determination of alkaline phosphatase (ALP). Bone sialoprotein (BSP) and OPG mRNA expressions were done by RT-PCR. beta-Glycerophosphate was able to induce calcification in human smooth muscle cells from a series of donors after variable time in culture. Decreased OPG amounts were observed from the cells during the accelerated calcification phase. High dose of insulin (1,000 microU/ml) accelerated the calcification, whereas lower concentrations (200 microU/ml) did not. Calcified cells expressed ALP and BSP activity in high levels. In conclusion, high concentration of insulin enhances in vitro-induced calcification in VSMCs. Altered OPG levels during the calcification raise the possibility that OPG may have a potent function in regulating the calcification process or it may represent a consequence of mineralization. Effects of insulin and modulations by OPG on the calcification process in arterial cells may play a role in the development of calcifications as part of the diabetic macroangiopathy.

Alkaline Phosphatase↗
PubMed2004

Clinical implication of cerebral artery calcification on brain CT.

BACKGROUND AND PURPOSE: Arterial calcification is a process of atherosclerosis, usually taking place within advanced atheromatous plaque. In the coronary arteries, calcification seen on computed tomography (CT) often indicates severe stenosis, and is noted in almost all patients with coronary symptoms. Calcification of the cerebral arteries is also frequently observed on brain CT, but its clinical significance has yet to be clarified. To evaluate the clinical significance of cerebral arterial calcification on brain CT, we investigated the angiographic and transcranial Doppler ultrasonography (TCD) findings of calcified cerebral arteries. METHODS: The subjects were 57 patients with ischemic stroke, all of whom underwent brain CT, digital subtraction cerebral angiography and TCD. Stroke subtypes were defined according to TOAST classification. Two clinicians who were blinded in respect to the patients' clinical history and to each other's interpretation, determined the presence of cerebral arterial calcification and the degree of angiographic stenosis. RESULTS: Cerebral artery calcification was noted in 23 patients (40%) out of a total of 46 arteries, consisting of 23 internal carotid, 15 vertebral, 5 basilar, 2 middle cerebral and 1 anterior cerebral artery. The patients with calcification were significantly older and more hypertensive than those without calcification. All the patients with calcification showed either large artery atherosclerosis or lacunar stroke. Hemodynamic alterations measured by TCD were rarely observed in calcified arteries. The severity and extent of the atherosclerotic changes were significantly greater in the patients with calcification than those without calcification. CONCLUSION: These results suggest that cerebral arterial calcification does not directly indicate hemodynamically significant atherosclerotic stenosis involving calcified segments, but indicates the underlying etiology of either large artery atherosclerosis or lacunar stroke, and raises the possibility of a diffuse atherosclerotic process being present in the cerebral circulation.

Adult↗