Factors associated with coronary artery calcification in young female patients with SLE.

BACKGROUND: With improved survival rates of patients with systemic lupus erythematosus (SLE), damage such as accelerated atherosclerosis gains increasing importance. OBJECTIVE: To identify the prevalence of coronary artery calcifications (CAC) in asymptomatic patients. METHODS: Electron beam tomography (EBT) was performed in 75 female patients with SLE aged <50. The results were correlated with traditional and SLE related factors associated with CAC. 49 women with symptomatic coronary heart disease (CHD) and 279 women without CHD were also analysed. RESULTS: Overall, 21/75 (28%) patients had CAC. Low HDL cholesterol levels <1.40 mmol/l (p=0.03, OR=1.8, 67% v 39%) and cigarette smoking (p=0.01, OR=5.7, 76% v 44%) were identified as factors associated with CAC. Hypertension and high cholesterol were more common in women with CHD (p<0.01) than in those without CHD. SLE related factors were proteinuria (1331 v 465 mg/day, p=0.02), impaired renal function (p=0.02, OR=2.6, 26% v 6%), and high C3 levels (p=0.04, OR=1.8, 65% v 38%). High C3 levels were also more common in symptomatic CHD (p=0.02). The prevalence of Sm antibodies was lower in patients with CAC (15% v 42%, p=0.03). In a multivariate analysis, cigarette smoking, reduced renal function, high C3, and a cumulative steroid dose above 30 g were the most important CAC associated factors in the lupus cohort. CONCLUSION: A subgroup of patients with SLE with CAC without any clinical symptoms of CHD was identified by EBT. Therefore, EBT is useful for assessing asymptomatic atherosclerosis in this group.

Coronary calcifications in young patients with first, unheralded myocardial infarction: a risk factor matched analysis by electron beam tomography.

OBJECTIVE: To compare the presence and extent of coronary calcifications in young patients with first, unheralded acute myocardial infarction with matched controls without a history of coronary artery disease. METHODS: In 102 patients under 60 years of age (19-59 years, mean 41 years; 88% male), electron beam tomography was done 1-14 days after acute myocardial infarction, before any coronary intervention. Coronary calcifications were quantified using the Agatston score. Age related calcium centiles were determined based on the Mayo Clinic "epidemiology of coronary calcification" study, and results were compared with a group of 102 controls without coronary artery disease, matched for sex, age, and risk factors. RESULTS: Calcifications were present in 95.1% of patients with acute myocardial infarction and in 59.1% of controls (p = 0.008). The mean (SD) Agatston score was 529 (901) in the infarct patients versus 119 (213) in the controls (p < 0.001). An Agatston score above the 50th centile was present in 87.2% of infarct patients and 47.0% of controls (p = 0.006), and above the 90th centile in 60.7% of infarct patients and only 5.8% of controls (p = 0.001). CONCLUSIONS: In young patients with their first, unheralded acute myocardial infarction, the presence and extent of coronary calcium are significantly greater than in matched controls.

Overlapping cross-sections significantly improve the reproducibility of coronary calcium measurements by electron beam tomography: a phantom study.

PURPOSE: We conducted phantom studies to investigate whether overlapping cross-sections and volumetric scoring would significantly improve interscan reproducibility of electron beam tomography (EBT) for coronary artery calcium quantification. METHOD: Fifteen phantoms simulating various amounts of coronary calcification were scanned in five different positions with a slice thickness of 3.0 mm and a table feed of 3.0, 2.5, and 2.0 mm. For the conventional "Agatston score" and a "volume score" (total volume of calcified lesions), interscan variabilities were compared between the three image acquisition protocols. RESULTS: Agatston score variability was significantly lower for the 2.0 mm table feed than for the 3.0 or 2.5 mm table feed (3.0 mm: 22.9 +/- 10.3%; 2.5 mm: 13.6 +/- 8.2%; 2.0 mm: 8.9 +/- 5.5%). Volume score variability was significantly lower for 2.5 and 2.0 mm table feed than for 3.0 mm table feed (3.0 mm: 21.7 +/- 11.0%; 2.5 mm: 10.9 +/- 5.9%; 2.0 mm: 9.8 +/- 5.9%). CONCLUSION: Overlapping cross-sections, especially in combination with volumetric scoring, significantly improved interscan reproducibility of EBT calcium quantification in a phantom study.

Variability of repeated coronary artery calcium measurements by electron beam tomography.

In 120 patients, the mean interscan variability of coronary calcium quantification by electron beam tomography was 19.9% (median 7.8%) for the traditional calcium score, and 16.2% (median 5.7%) for volumetric scoring. Although this difference was not significant, there was a significant influence of the total amount of calcium, number of acquired images, and image noise on interscan reproducibility.

Rhabdomyolysis and acute renal failure in a cardiac transplant recipient due to multiple drug interactions.

BACKGROUND: The 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors lovastatin and simvastatin have been associated with rhabdomyolysis in cardiac transplant recipients. Herein, we report a case of a 52-year-old male recipient of a cardiac transplant who developed rhabdomyolysis and acute renal failure caused by simvastatin precipitated by multiple drug interactions. METHODS: The patient had a history of cardiac transplantation (5 years before) and presented with a 2-day history of dark urine preceded by 2 weeks of diffuse myalgias. He had been maintained on cyclosporine throughout the entire post-transplant period. Simvastatin was added and pravastatin was discontinued 2 months before admission. Two weeks before the onset of muscle symptoms, digoxin and verapamil were started for new-onset atrial fibrillation. Creatinine phosphokinase levels peaked at 950,000 IU with serum creatinine of 3.3 mg/dL (baseline, 1.8 mg/dL). RESULTS: Review of the medication history indicates a temporal association between the addition of 3 drugs (simvastatin, verapamil, and digoxin) to the medication regimen already containing cyclosporine and the episode of rhabdomyolysis. All of these drugs are cytochrome P450 3A4 and/or P-glycoprotein substrates that are known from previous pharmacokinetic studies to individually produce substantial increases in levels of simvastatin. CONCLUSION: We believe this case illustrates that avoiding the use of drugs that are cytochrome P450 3A4 and/or P-glycoprotein substrates reduces the risk of rhabdomyolysis caused by 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors.