Quantification of anatomical aortic valve area by multi-detector computed tomography: A pilot 3D-morphological modeling of the stenotic aortic valve.

BACKGROUND: Aortic-valve-stenosis (AS) is a frequent degenerative valvular-disease and carries dismal outcome under-medical-treatment. Transvalvular pressure gradient reflects severity of the valve-disease but is highly dependent on flow-conditions and on other valvular/aortic characteristics. Alternatively, aortic-valve-area (AVA) represents a measure of aortic-valve lesion severity conceptually essential and practically widely-recognized but exhibits multiple-limitations. METHODS: We analyzed the 4D multi-detector computed tomography(MDCT) of 20 randomly selected patients with severe AS. For each-patient, we generated the 3D-model of the valve and of its calcifications, and we computed the anatomical AVA accounting for the 3D-morphology of the leaflets in three-different-ways. Finally, we compared our results vs. Doppler-based AVAE measurements and vs. 2D-planimetric AVA-measurements. RESULTS: 3D-reconstruction and identification of the cusps were successful in 90% of the cases. The calcification patterns where highly-variable over patients, ranging from multiple small deposits to wide and c-shaped deposits running from commissure-to-commissure. AVAE was 82 ±â€¯15 mm2. When segmenting 18 image planes, AVATight, AVAProj-Ann, AVAProj-Tip and their average AVAAve were equal to 80 ±â€¯16, 88 ±â€¯20, 93 ±â€¯21 and 87 ±â€¯19 mm2, respectively, while AVAPlan was equal to 143 ±â€¯50 mm2. Linear-regression of the three measurements vs. AVAE yielded regression slopes equal to 1.26, 1.13 and 0.93 for AVAProj-Ann, AVAProj-Tip and AVATight, respectively. The respective Pearson-coefficients were 0.85,0.86 and 0.90. Conversely, when comparing AVAPlan vs. AVAE, linear regression yielded a slope of 1.73 and a Pearson coefficient of 0.53. CONCLUSIONS: We described a new-method to obtain a set of flow-independent quantifications that complement pressure gradient measurements and combine the advantages of previously proposed methods, while bypassing the corresponding-limitations.

Left main coronary stenosis as a late complication of percutaneous angioplasty:an old problem,but still a problem / 老年心脏病学杂志（英文版）

Objective Accelerated left main coronary stenosis (LMCS) is a known potential late complication of coronary artery catheter procedures. The aim of this study was to assess the current occurrence of LMCS as a delayed complication of percutaneous angioplasty (PTCA) of the left coronary branches in our institution. Methods The medical records of patients referred for coronary artery by-pass surgery from the same Cardiology Unit in the January 2003 to December 2006 period and presenting a significant (> 50%) LMCS as a new finding following a PTCA of the left coronary artery branches, were reviewed. Patients with retrospective evidence of any LMCS at previous coronary angiographies preceding the percutaneous procedure were excluded. Results Thirty-seven patients (5 females, mean age 71.1±8.6 years) out of 944 (4%) having undergone a PTCA, fulfilled the inclusion criteria, 19 (51%) after a procedure also involving the LAD coronary artery. Extraback-up guiding catheters were used in most cases. Use of multiple wires or balloons was observed in 3 cases (8%). Rotablator and proximal occlusion device were used in one case respectively (3%). Twenty patients (54%) have had more than one percutaneous coronary intervention on the left coronary branches. The mean time elapsed from the first angioplasty and surgical intervention was 18.1±7.8 months. Conclusions The potential occurrence of LMCS following a percutaneous intervention procedure, especially when complicated and repeated, should not be underestimated in the current era. This evidence may offer the rationale to schedule non-invasive imaging tests to monitor left main coronary patency after the procedure as well as to fuel further research to develop less traumatic materials.