Comparison of Cine-MRI and Transthoracic Echocardiography for the Assessment of Aortic Root Diameters in Patients with Suspected Marfan Syndrome.

PURPOSE: Patients with Marfan syndrome require repeated imaging for monitoring of aortic root aneurysms. Therefore, we evaluated the agreement and reproducibility of cine-MRI and echocardiography measurements of the sinuses of Valsalva in patients with suspected Marfan syndrome. MATERIALS AND METHODS: 51 consecutive patients with suspected Marfan syndrome were prospectively examined using cine-MRI and echocardiography. Two readers independently measured aortic root diameters at the level of the sinuses of Valsalva in both cine-MRI and echocardiography. Statistics included intraclass correlation coefficient, Pearson correlation coefficient, Bland-Altman analysis, and two-sided t-test. RESULTS: In 38 of the 51 individuals (74.5 %), the diagnosis of Marfan syndrome was established according to the criteria of the Ghent-2 nosology. Cine-MRI measurements of the sinuses of Valsalva revealed a strong correlation with echocardiography (r = 0.929), but a statistically significant bias of -1.0  mm (p < 0.001). The mean absolute diameter for sinuses of Valsalva obtained by cine-MRI was 32.3  ±  5.8 mm as compared to 33.4  ±  5.4 mm obtained by echocardiography. Interobserver agreement of measurements of the sinuses of Valsalva was higher for cine-MRI than for echocardiography (p = 0.029). CONCLUSION: Despite small, but statistically significant differences in terms of agreement and reproducibility, cine-MRI and echocardiographic measurements of aortic root diameters provide comparable results without a significant clinical difference. Therefore both techniques may be used for monitoring of the aortic root in patients with Marfan syndrome.

Reoperation after the Ross procedure: incidence, management, and survival.

BACKGROUND: The risk of reoperation on the autograft and homograft is the major long-term drawback of the Ross procedure. The incidence and clinical implications of reoperations after the Ross procedure are reported. METHODS: Between March 1992 and February 2010, 336 consecutive patients had a Ross procedure (mean follow-up, 6.2±4.9 years). Autograft implant technique was freestanding root replacement in 269 patients, subcoronary implantation in 52 patients and a modified root replacement with the autograft included in a Valsalva tube graft in 15. RESULTS: Subsequently, 38 patients (11.3%) underwent reoperations, for autograft dilatation in 23 and a significant autograft insufficiency in 9, at 9.6±3.7 years and 2.6±3.9 years, respectively. Aortic and pulmonary infective endocarditis occurred in 3 patients. Three patients underwent a non valve-related cardiac reoperation. Three patients received a transcatheter pulmonary valve implantation after 12.2±1.7 years. At 15 years, freedoms for autograft and homograft explantation (with 95% confidence interval) were 83.3% (77.4%- to 9.2%) and 92.8% (87.6% to 97.9%), respectively. Native aortic valve regurgitation, indexed aortic annulus diameter exceeding 1.35 cm/m2 and autograft diameter were risk factors for dilated autograft reoperation (hazard ratio, 3.23 [95% confidence interval, 1.19 to 8.81], p=0.02; 3.83 [0.9 to 16.33], p=0.07 and 1.2 per mm [1.01 to 1.41], p=0.03), respectively. CONCLUSIONS: Autograft dilatation was the leading cause of reoperation in patients who underwent root replacement. Long-term follow-up is mandatory to determine whether modifications of the operative technique could limit autograft dilatation.

Alpha2beta1 integrin and development of atherosclerosis in a mouse model: assessment of risk.

OBJECTIVE: The alpha2beta1 integrin serves as a collagen or collagen/laminin receptor on many cell types, including endothelial cells and platelets. Many studies indicate that the alpha2beta1 integrin is a critical mediator of platelet adhesion to collagen. Epidemiologic studies suggest a direct correlation between the genetically determined platelet surface density of the alpha2beta1 integrin and the risk of thrombotic diseases, such as myocardial infarction and stroke, in the young, which are well-established complications of atherosclerosis. We have now used the alpha2beta1 integrin-deficient mouse to evaluate the contributions of the alpha2beta1 integrin to the development of atherosclerosis. METHODS AND RESULTS: We generated wild-type (alpha2+/+) or alpha2beta1 integrin-deficient (alpha2-/-) mice that were also deficient in the apolipoprotein E (ApoE) gene (ApoE-/-) and compared atherosclerotic lesion development in alpha2+/+ ApoE-/- and alpha2-/- ApoE-/- mice that were fed a high-fat, cholesterol-containing diet for 6 or 15 weeks. Total lesional area did not differ significantly between the alpha2-null animals and the wild-type animals at either 6 or 15 weeks. CONCLUSIONS: Our results suggest that risk for arterial thrombotic disease associated with high-level alpha2beta1 integrin expression is not attributable to enhanced development of atherosclerosis per se but may rather be a consequence of thrombotic complications at the plaques.

Quantitative assessment of aortic atherosclerosis in APOE*3 Leiden transgenic mice and its relationship to serum cholesterol exposure.

Transgenic mice overexpressing the human dysfunctional apolipoprotein E variant, APOE*3 Leiden, develop hyperlipidemia and are highly susceptible to diet-induced atherosclerosis. In the present study, we investigated the effects of diet composition and feeding period on serum cholesterol exposure and the amount of atherosclerosis in the aortic sinus in these mice, using quantitative image analysis. On each of the three diets tested--a low-fat diet, a high-saturated-fat/cholesterol diet, and a high saturated-fat/high-cholesterol/0.5%-cholate diet--transgenic animals showed a marked hyperlipidemia compared with nontransgenic littermates. Measurement of the atherosclerotic lesion areas in cross sections of the aortic sinus in animals exposed to these three diets for up to 6 months showed a 5 to 10 times greater lesion area in transgenic mice compared with nontransgenic controls. Highly significant positive correlations were found between the log-transformed data on lesion area and serum cholesterol exposure (r = .82 to .85 for the 1-, 2-, and 3-month treatment groups), indicating that the hyperlipidemia is likely to be a major determinant in lesion formation. On the basis of these findings, we suggest that the APOE*3 Leiden mouse represents a promising model for intervention studies with hypolipidemic and antiatherosclerotic drugs.