Calcification des grandes artères et risque de fracture ostéoporotique [Aortic calcification and the risk of osteoporotic fractures].

Osteoporosis and atherosclerosis seem to be epidemiologically correlated. Several medical conditions are risk factors for both osteoporosis and atheromatosis (i.e. age, diabetes, end stage renal disease, sedentarity, smoking), but a common pathogenic link may be present beyond this. The burden of cardiovascular events and of osteoporotic fracture is considerable for the health care system in term of costs and resources. However, both diseases are rarely managed together. This article is a review of the recent studies in this new field.

Effect of oral calcium carbonate on aortic calcification in apolipoprotein E-deficient (apoE-/-) mice with chronic renal failure.

BACKGROUND: In chronic kidney disease (CKD) patients, the intake of calcium-based phosphate binders is associated with a marked progression of coronary artery and aortic calcification, in contrast to patients receiving calcium-free phosphate binders. The aim of this study was to reexamine the role of calcium carbonate in vascular calcification and to analyse its effect on aortic calcification-related gene expression in chronic renal failure (CRF). METHODS: Mice deficient in apolipoprotein E underwent either sham operation or subtotal nephrectomy to create CRF. They were then randomly assigned to one of the three following groups: a control non-CRF group and a CRF group fed on standard diet, and a CRF group fed on calcium carbonate enriched diet, for a period of 8 weeks. Aortic atherosclerotic plaque and calcification were evaluated using quantitative morphologic image processing. Aortic gene and protein expression was examined using immunohistochemistry and Q-PCR methods. RESULTS: Calcium carbonate supplementation was effective in decreasing serum phosphorus but was associated with a higher serum calcium concentration. Compared with standard diet, calcium carbonate enriched diet unexpectedly induced a significant decrease of both plaque (p<0.05) and non-plaque-associated calcification surface (p<0.05) in CRF mice. It also increased osteopontin (OPN) protein expression in atherosclerotic lesion areas of aortic root. There was also a numerical increase in OPN and osteoprotegerin gene expression in total thoracic aorta but the difference did not reach the level of significance. Finally, calcium carbonate did not change the severity of atherosclerotic lesions. CONCLUSION: In this experimental model of CRF, calcium carbonate supplementation did not accelerate but instead decreased vascular calcification. If our observation can be extrapolated to humans, it appears to question the contention that calcium carbonate supplementation, at least when given in moderate amounts, necessarily enhances vascular calcification. It is also compatible with the hypothesis of a preponderant role of phosphorus over that of calcium in promoting vascular calcification in CRF.

Endoleak and in-stent thrombus detection with CT angiography in a thoracic aortic aneurysm phantom at different tube energies using filtered back projection and iterative algorithms.

PURPOSE: To determine the lower limit of dose reduction with hybrid and fully iterative reconstruction algorithms in detection of endoleaks and in-stent thrombus of thoracic aorta with computed tomographic (CT) angiography by applying protocols with different tube energies and automated tube current modulation. MATERIALS AND METHODS: The calcification insert of an anthropomorphic cardiac phantom was replaced with an aortic aneurysm model containing a stent, simulated endoleaks, and an intraluminal thrombus. CT was performed at tube energies of 120, 100, and 80 kVp with incrementally increasing noise indexes (NIs) of 16, 25, 34, 43, 52, 61, and 70 and a 2.5-mm section thickness. NI directly controls radiation exposure; a higher NI allows for greater image noise and decreases radiation. Images were reconstructed with filtered back projection (FBP) and hybrid and fully iterative algorithms. Five radiologists independently analyzed lesion conspicuity to assess sensitivity and specificity. Mean attenuation (in Hounsfield units) and standard deviation were measured in the aorta to calculate signal-to-noise ratio (SNR). Attenuation and SNR of different protocols and algorithms were analyzed with analysis of variance or Welch test depending on data distribution. RESULTS: Both sensitivity and specificity were 100% for simulated lesions on images with 2.5-mm section thickness and an NI of 25 (3.45 mGy), 34 (1.83 mGy), or 43 (1.16 mGy) at 120 kVp; an NI of 34 (1.98 mGy), 43 (1.23 mGy), or 61 (0.61 mGy) at 100 kVp; and an NI of 43 (1.46 mGy) or 70 (0.54 mGy) at 80 kVp. SNR values showed similar results. With the fully iterative algorithm, mean attenuation of the aorta decreased significantly in reduced-dose protocols in comparison with control protocols at 100 kVp (311 HU at 16 NI vs 290 HU at 70 NI, P ≤ .0011) and 80 kVp (400 HU at 16 NI vs 369 HU at 70 NI, P ≤ .0007). CONCLUSION: Endoleaks and in-stent thrombus of thoracic aorta were detectable to 1.46 mGy (80 kVp) with FBP, 1.23 mGy (100 kVp) with the hybrid algorithm, and 0.54 mGy (80 kVp) with the fully iterative algorithm.

Primary isolated aortic valve surgery in octogenarians.

We reviewed our surgery registry, to identify predictive risk factors for operative results, and to analyse the long-term survival outcome in octogenarians operated for primary isolated aortic valve replacement (AVR). A total of 124 consecutive octogenarians underwent open AVR from January 1990 to December 2005. Combined procedures and redo surgery were excluded. Selected variables were studied as risk factors for hospital mortality and early neurological events. A follow-up (FU; mean FU time: 77 months) was obtained (90% complete), and Kaplan-Meier plots were used to determine survival rates. The mean age was 82+/-2.2 (range: 80-90 years; 63% females). Of the group, four patients (3%) required urgent procedures, 10 (8%) had a previous myocardial infarction, six (5%) had a previous coronary angioplasty and stenting, 13 patients (10%) suffered from angina and 59 (48%) were in the New York Heart Association (NYHA) class III-IV. We identified 114 (92%) degenerative stenosis, six (5%) post-rheumatic stenosis and four (3%) active endocarditis. The predicted mortality calculated by logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 12.6+/-5.7%, and the observed hospital mortality was 5.6%. Causes of death included severe cardiac failure (four patients), multi-organ failure (two) and sepsis (one). Complications were transitory neurological events in three patients (2%), short-term haemodialysis in three (2%), atrial fibrillation in 60 (48%) and six patients were re-operated for bleeding. Atrio-ventricular block, myocardial infarction or permanent stroke was not detected. The age at surgery and the postoperative renal failure were predictors for hospital mortality (p value <0.05), whereas we did not find predictors for neurological events. The mean FU time was 77 months (6.5 years) and the mean age of surviving patients was 87+/-4 years (81-95 years). The actuarial survival estimates at 5 and 10 years were 88% and 50%, respectively. Our experience shows good short-term results after primary isolated standard AVR in patients more than 80 years of age. The FU suggests that aortic valve surgery in octogenarians guarantees satisfactory long-term survival rates and a good quality of life, free from cardiac re-operations. In the era of catheter-based aortic valve implantation, open-heart surgery for AVR remains the standard of care for healthy octogenarians.

Mycobacterium tuberculosis aortic graft infection with recurrent hemoptysis: a case report.

INTRODUCTION: Mycobacterium tuberculosis may cause a large variety of clinical presentations due to its ability to disseminate by contiguity or hematogenously. Tuberculosis may remain undiagnosed for years due to the chronic course of the disease, with potentially life-threatening long-term complications. CASE PRESENTATION: In this case report, we describe a tuberculous aortic graft infection in a 72-year-old man documented by polymerase chain reaction and cultures. The patient presented with three episodes of hemoptysis following a remote history of miliary tuberculosis. The infection was treated by graft replacement and prolonged antimycobacterial therapy. CONCLUSION: Tuberculous infection of a vascular graft is an uncommon complication, but should be considered in patients with an intravascular device and a history of previous tuberculosis, especially when hematogenous spread may have occurred a few months after surgery, or when an active mycobacterial infection is present in close proximity to the graft.

Quantification of aortic flow by phase-contrast magnetic resonance in patients with bicuspid aortic valve.

AIMS: Bicuspid aortic valve (BAV) causes complex flow patterns in the ascending aorta (AAo), which may compromise the accuracy of flow measurement by phase-contrast magnetic resonance (PC-MR). Therefore, we aimed to assess and compare the accuracy of forward flow measurement in the AAo, where complex flow is more dominant in BAV patients, with flow quantification in the left ventricular outflow tract (LVOT) and the aortic valve orifice (AV), where complex flow is less important, in BAV patients and controls. METHODS AND RESULTS: Flow was measured by PC-MR in 22 BAV patients and 20 controls at the following positions: (i) LVOT, (ii) AV, and (iii) AAo, and compared with the left ventricular stroke volume (LVSV). The correlation between the LVSV and the forward flow in the LVOT, the AV, and the AAo was good in BAV patients (r = 0.97/0.96/0.93; P < 0.01) and controls (r = 0.96/0.93/0.93; P < 0.01). However, in relation with the LVSV, the forward flow in the AAo was mildly underestimated in controls and much more in BAV patients [median (inter-quartile range): 9% (4%/15%) vs. 22% (8%/30%); P < 0.01]. This was not the case in the LVOT and the AV. The severity of flow underestimation in the AAo was associated with flow eccentricity. CONCLUSION: Flow measurement in the AAo leads to an underestimation of the forward flow in BAV patients. Measurement in the LVOT or the AV, where complex flow is less prominent, is an alternative means for quantifying the systolic forward flow in BAV patients.

Endovascular thoracic aortic aneurysm repair without angiography.

OBJECTIVE: : Intravascular ultrasound (IVUS) generates high definition circumferential cross-sectional images and provides real-time readout of vascular dimensions, including visualization of vessel branches. We have used it as an alternative to angiography in the endovascular thoracic aneurysm repair work-up. METHODS: : Out of consecutive 203 patients with descending thoracic aortic aneurysm, 89 (43.8%) received endovascular treatment [mean age, 68 ± 8 years; range, 29-82; male, 79 (88.7%); female, 10 (11.3%)] without using angiography during the endovascular procedure. IVUS (6 F, 12.5 MHz probe or 10 F 9 MHz) coupled with fluoroscopy for the placement of radiopaque markers was used for target site identification, landing zone measurement, device positioning, and assessment of endovascular repair. RESULTS: : Hospital mortality was 4/89 (4.5%). Number of devices implanted in each patient was 1.2 (range, 1-3). X-ray exposure time was 12 ± 8 minutes. Median procedure time was 63 ± 20 minutes. Conversion to open surgery was necessary in one patient (1.1%) because of aortic dissection. In nine patients (10.1%) left subclavian artery was covered because of a short neck. Two patients (2.2%) had vascular access lesions and required surgical repair. One patient developed paraplegia (1.1%). Early endoleak was observed in eight patients (8.9%) and 4 (4.5%) required additional procedures (proximal or distal extensions). Late conversion was necessary in one patient (1.1%). CONCLUSIONS: : IVUS provides all information necessary for device selection, target site identification as well as safe and correct deployment of thoracic endoprostheses and makes periprocedural angiography unnecessary, thus avoiding the risk of renal failure because of contrast medium.

Bilateral symmetry of radial pulse in high-level tennis players: implications for the validity of central aortic pulse wave analysis.

BACKGROUND: Reconstruction of the central aortic pressure wave from the noninvasive recording of the radial pulse with applanation tonometry has become a standard tool in the field of hypertension. It is not presently known whether recording the radial pulse on the dominant or the nondominant side has any effect on such reconstruction. METHOD: We carried out radial applanation tonometry on both forearms in young, healthy, male volunteers, who were either sedentary (n = 11) or high-level tennis players (n = 10). The purpose of including tennis players was to investigate individuals with extreme asymmetry between the dominant and nondominant upper limb. RESULTS: In the sedentary individuals, forearm circumference and handgrip strength were slightly larger on the dominant (mean +/- SD respectively 27.9 +/- 1.5 cm and 53.8 +/- 10 kg) than on nondominant side (27.3 +/- 1.6 cm, P < 0.001 vs. dominant, and 52.1 +/- 11 kg, P = NS). In the tennis players, differences between sides were more conspicuous (forearm circumference: dominant 28.0 +/- 1.7 cm nondominant 26.4 +/- 1.5 cm, P < 0.001; handgrip strength 61.4 +/- 10.8 vs. 53.4 +/- 9.7 kg, P < 0.001). We found that in both sedentary individuals and tennis players, the radial pulse had identical shape on both sides and, consequently, the reconstructed central aortic pressure waveforms, as well as derived indices of central pulsatility, were not dependent on the side where applanation tonometry was carried out. CONCLUSION: Evidence from individuals with maximal asymmetry of dominant vs. nondominant upper limb indicates that laterality of measurement is not a methodological issue for central pulse wave analysis carried out with radial applanation tonometry.

Treatment of congenital aortic valve stenosis: impact of the Ross operation.

GOAL: To evaluate the impact of the Ross operation, recently (1997) introduced in our unit, for the treatment of patients with congenital aortic valve stenosis. METHODS: The period from January 1997 to December 2000 was compared with the previous 5 years (1992-96). Thirty-seven children (< 16 yrs) and 49 young adults (16-50 yrs) with congenital aortic valve stenosis underwent one of these treatments: percutaneous balloon dilatation (PBD), aortic valve commissurotomy, aortic valve replacement and the Ross operation. The Ross operation was performed in 16 patients, mean age 24.5 yrs (range 9-46 yrs) with a bicuspid stenotic aortic valve, 7/10 adults with calcifications, 2/10 adults with previous aortic valve commissurotomy, 4/6 children with aortic regurgitation following PBD, and 1/6 children who had had a previous aortic valve replacement with a prosthetic valve and aortic root enlargement. RESULTS: PBD was followed by death in two neonates (fibroelastosis); all other children survived PBD. Although there were no deaths, PBD in adults was recently abandoned, owing to unfavourable results. Aortic valve commissurotomy showed good results in children (no deaths). Aortic valve replacement, although associated with good results (no deaths), has been recently abandoned in children in favour of the Ross operation. Over a mean follow-up of 16 months (2-40 months) all patients are asymptomatic following Ross operation, with no echocardiographic evidence of aortic valve regurgitation in 10/16 patients and with trivial regurgitation in 6/16 patients. CONCLUSIONS: The approach now for children and young adults with congenital aortic valve stenosis should be as follows: (1) PBD is the first choice in neonates and infants; (2) Aortic valve commissurotomy is the first choice for children, neonates and infants after failed PBD; (3) The Ross operation is increasingly used in children after failed PBD and in young adults, even with a calcified aortic valve.

Reduction of small infrarenal abdominal aortic aneurysm expansion rate by statins.

BACKGROUND: To evaluate the effect of statins on the annual expansion rate (ER) of small infrarenal abdominal aortic aneurysms (AAA). PATIENTS AND METHODS: All patients under regular surveillance for small AAA between January 2000 and September 2007, in the Department of Angiology, Lausanne University Hospital, were included. Inclusion criteria were baseline abdominal aortic diameter between 25 and 55 mm, at least two measurements of AAA diameter and a minimum follow up of 6 months. Patients with Marfan disease, infectious or inflammatory AAA, and patients with prior AAA repair were excluded. The influence of statin use and other factors on ER were examined by bivariate and multivariate analysis. RESULTS: Among 589 patients who underwent an abdominal aorta evaluation, 94 patients (89 % men, mean age 69.1 years) were finally included in the analysis. Baseline AAA size was 39.9 ± 7.7 mm (mean±SE) and 48.7 ± 8.4 mm at end of follow-up. Patients had a regular aneurysm size assessment during 38.5 ± 27.7 months. Mean ER was 3.59 mm/y (± 2.81). The 50 patients who were treated with statin during the study period had a lower ER compared to the 44 controls (2.91 vs 4.37 mm/year, p = 0.01). CONCLUSIONS: This study confirms the considerable individual variations in the AAA expansion rate, and emphasizes the need for regular aortic diameter assessments. In this study, patients treated with statin demonstrate a significant decrease in the ER compared to controls. This finding need to be evaluated in prospective interventional studies powered to demonstrate the potential benefit of statin treatment.

Unusual calcification of the right kidney.

For economic reasons, the tendency in western communities is to simplify the investigations for a given pathology. This case is typically the one where some more money has to be invested to achieve the correct diagnosis.

Surgery for ruptured thoracic and thoraco-abdominal aortic aneurysms.

OBJECTIVE: To assess the outcome of patients with ruptured descending thoracic and thoracoabdominal aortic aneurysms undergoing emergency repair, in comparison to elective surgery for chronic lesions. METHODS: A prospective study of 100 consecutive patients operated upon the descending aorta (1-8 segments) using proximal unloading and distal protection with partial cardiopulmonary bypass, heparin surface-coated perfusion equipment and low systemic heparinization (loading dose 100 IU/kg, activated coagulation time > 180 s), staged cross-clamping, sealed grafts and graft inclusion. RESULTS: Arteriosclerotic lesions were present in 53/100 patients (53%) for all, 30/53 (56%) for chronic, and 21/33 (63%) for ruptured, aneurysms (NS). Dissecting lesions were found in 38/100 patients (38%) for all, 20/53 (38%) for chronic, and 8/33 (24%) for ruptured aneurysms (NS). Preoperative hematocrit was 38 +/- 6% for all, 40 +/- 5% for chronic, and 33 +/- 5% for ruptured aneurysmal patients (P < 0.001 ruptured versus chronic). The extent of aortic repair (1-8 segments) was 3.3 +/- 1.6 for all, 3.5 +/- 1.5 for chronic, and 3.2 +/- 1.4 for ruptured, aneurysms (NS). Transdiaphragmatic repair was performed in 51/100 (51%) of all, 28/53 (53%) of chronic, and 17/33 (51%) of ruptured aneurysms (NS). Aortic cross-clamp time was 38 +/- 21 min for all, 39 +/- 24 min for chronic, and 38 +/- 17 min for ruptured, aneurysmal patients (NS). The amount of red cells washed and autotransfused was 2792 +/- 2239 ml in all, 3143 +/- 2531 ml in chronic, and 2074 +/- 1350 ml in ruptured, aneurysmal patients (P < 0.025). The amount of packed red cells required was 2181 +/- 1830 ml for all, 1736 +/- 1333 ml for chronic, and 2947 +/- 2395 ml for ruptured aneurysmal patients (P < 0.010). Thirty-day mortality was 9/100 (9%) for all, 3/53 (6%) for chronic, and 5/33 (15%) for ruptured aneurysmal patients (NS). Parapareses/plegias occurred in 9/100 (9%) of all, 6/53 (11%) of chronic, and 3/33 (9%) of ruptured, aneurysmal patients (NS). Stepwise regression analysis identified aortic cross-clamp time as a predictor of early mortality (P = 0.002) and parapareses and paraplegias (P = 0.001). Age (P = 0.001), extent of repair (P = 0.008) and preoperative hematocrit (P = 0.001) were predictors for homologous transfusion requirements. CONCLUSION: Emergency repair of ruptured descending thoracic and thoracoabdominal aortic aneurysms can be achieved with acceptable results.

Surgery for aortic coarctation: a 30 years experience.

OBJECTIVE: A retrospective study to review the experience of a single center with surgery for aortic coarctation over a period of 30 years (1970-1999). METHODS: Criteria for inclusion: (a) aortic coarctation, isolated or associated with congenital heart defect; (b) surgery between 1970 and 1999. Data recorded: (1) date of surgery; (2) age at surgery; (3) associated lesions; (4) surgical technique; (5) simultaneous surgical procedures; (6) early and late surgical results in term of: (a) deaths; (b) need for reoperation because of re-coarctation or other cardiac lesion; (c) residual/recurrent pressure gradient, evaluated at cuff/Doppler at rest; (d) systemic hypertension, requiring medical treatment. RESULTS: One hundred and forty-one patients underwent surgery for aortic coarctation: 30 neonates, 29 infants, 45 children and 37 adults. Associated lesions were found in 8/37 (=21.6%) adults and in 73/104 (=70.1%) pediatric patients. There were no hospital deaths. During the follow-up there were one late death in the adults group (1/37=2.7%) and three late deaths in the pediatric group (3/104=2.9%), all unrelated with aortic coarctation. Re-operation because of re-coarctation occurred only in ten late survivors of the pediatric group (10/101=9.9%), 9/10 operated on before 1980 (P<0.00001). End-to-end anastomosis, enlarged to the aortic arch in neonates, was associated with the lowest incidence of re-coarctation (P<0.005). A significant (>20 mmHg at rest) pressure gradient was found in none of the adults, and in seven of the 91 pediatric patients (7/91=7.7%) late survivors. Three adults (3/36=8.3%) late survivors are on medical treatment to control systemic hypertension. CONCLUSIONS: The long-term results of our retrospective study confirm that surgery has to be considered the gold standard for the treatment of aortic coarctation. The interventional angioplasty techniques have to provide long-term outcome at least similar to the results obtained with surgery.