Comparison of multislice computed tomography findings between bicuspid and tricuspid aortic valves before and after transcatheter aortic valve implantation.

AIMS: This study sought to compare the multislice computed tomography (MSCT) characteristics of bicuspid aortic valves (BAV) and tricuspid aortic valves (TAV) before and after implantation of the CoreValve (Medtronic, Santa Rosa, California) or the Edwards SapienXT (Edwards Lifesciences, Irvine, CA). METHODS AND RESULTS: From March 2009 to March 2013, a total of 67 TAVI patients who had both pre- and post-procedural MSCT were studied. Eleven patients underwent TAVI in BAV with the CoreValve (n = 6) or SapienXT (n = 5) and 56 patients underwent TAVI in TAV with the CoreValve (n = 38) or SapienXT (n = 18). The BAV group was similar to the TAV group except for a higher pre-procedural mean pressure gradient (53.1 ± 17.4 vs. 48.8 ± 20.4 mm Hg, P = 0.03), a larger annulus perimeter (89.3 ± 9.0 vs. 81.8 ± 8.1 mm, P = 0.03) and a higher aortic valve calcium volume (1262.7 ± 396.0 vs. 556.4 ± 461.9 mm(3) , P < 0.01). In the CoreValve group, post-procedural mean pressure gradient was significantly higher in the BAV group (11.0 ± 2.6 vs. 8.2 ± 2.8 mm Hg, P = 0.04) and a smaller valve area/pre-annulus area ratio was observed at each level of the prosthesis (base of the stent frame 81.7% ± 14.9% vs. 94.7% ± 15.0%, P = 0.06, annulus level 74.3% ± 16.7% vs. 89.9% ± 10.5%, P = 0.03, leaflet level 64.6% ± 13.1% vs. 81.2% ± 13.2%, P < 0.01). This was not observed in the Edwards group. CONCLUSIONS: Compared to TAV, patients with BAV have higher gradients, larger annulus perimeters and more calcified valves. Higher post procedural gradient and valve underexpansion were frequently observed after CoreValve implantation. Further MSCT study is required to demonstrate the efficacy of TAVI in BAV.

Asymmetric dimethylarginine independently predicts fatal and nonfatal myocardial infarction and stroke in women: 24-year follow-up of the population study of women in Gothenburg.

OBJECTIVE: Asymmetrical dimethylarginine (ADMA) reduces nitric oxide by inhibiting nitric oxide synthase is associated with cardiovascular disease (CVD). Our study examined the association of ADMA with CVD prospectively in a healthy population-based cohort of women. METHODS AND RESULTS: We measured baseline ADMA of 880 women in the Population Study of Women in Gothenburg using high-performance liquid chromatography. After adjustment for traditional risk factors, creatinine clearance, and homocysteine using Cox models, the HR (95% CI in parentheses) of CVD end points at 24 years for a 0.15 micromol/L (1 SD) increase in ADMA were: all-cause mortality 1.12 (0.96, 1.32), fatal CVD 1.30 (1.04, 1.62), total CVD events 1.29 (1.09, 1.53). The top quintile (ADMA >or=0.71 micromol/L) compared with the bottom four-fifths, conferred a cumulative risk 22 versus 14%, relative risk 1.75 (95% CI 1.18, 2.59) and population attributable risk 12.7% of total CVD events, and further identified individuals who are at higher than expected risk based on the SCORE and Framingham systems. CONCLUSIONS: A 0.15 mumol/L increase in baseline ADMA levels is associated with approximately 30% increase in incident cardiovascular risk at 24 years in women after adjustment. ADMA levels >or=0.71 micromol/L enhances CVD risk assessment in women.

Improvement in the estimation of cardiovascular risk by carotid intima-medial thickness: A report from the Dublin Cardiohealth station study.

BACKGROUND: The 5th Joint Task Force European guidelines on cardiovascular disease (CVD) prevention recommend the measurement of carotid intima-media thickness (CIMT) in asymptomatic individuals at moderate risk (Class IIa). We aimed to evaluate the ability of CIMT to further risk stratify patients. DESIGN: Cross-sectional study. METHODS: Patients aged over 18 years free of known CVD at moderate, high, or very high risk of CVD were included. The Panasonic Cardiohealth station, a semi-automated ultrasound system, was used to detect carotid plaque and measure CIMT. Elevated CIMT was defined as =/> 0.9 mm. We analyzed the percentage of those at moderate risk reclassified after addition of CIMT. RESULTS: Two hundred patients were included (55% women, mean age 57 years, 12% diabetic); 64%, 23% and 13% were classified as moderate, high, and very high risk, respectively. Across these risk categories, 17%, 33%, and 46% had elevated IMT, p for trend < 0.001. With the addition of CIMT, 13.9% (95% CI: 5.7% to 22.1%) of women and 20.4% (95% CI: 8.7% to 32.1%) of men initially moderate risk were reclassified. CONCLUSIONS: CIMT measurement reclassifies a considerable percentage of those at moderate risk based on traditional risk factors alone.

Do optimal prognostic thresholds in continuous physiological variables really exist? Analysis of origin of apparent thresholds, with systematic review for peak oxygen consumption, ejection fraction and BNP.

BACKGROUND: Clinicians are sometimes advised to make decisions using thresholds in measured variables, derived from prognostic studies. OBJECTIVES: We studied why there are conflicting apparently-optimal prognostic thresholds, for example in exercise peak oxygen uptake (pVO2), ejection fraction (EF), and Brain Natriuretic Peptide (BNP) in heart failure (HF). DATA SOURCES AND ELIGIBILITY CRITERIA: Studies testing pVO2, EF or BNP prognostic thresholds in heart failure, published between 1990 and 2010, listed on Pubmed. METHODS: First, we examined studies testing pVO2, EF or BNP prognostic thresholds. Second, we created repeated simulations of 1500 patients to identify whether an apparently-optimal prognostic threshold indicates step change in risk. RESULTS: 33 studies (8946 patients) tested a pVO2 threshold. 18 found it prognostically significant: the actual reported threshold ranged widely (10-18 ml/kg/min) but was overwhelmingly controlled by the individual study population's mean pVO2 (r = 0.86, p<0.00001). In contrast, the 15 negative publications were testing thresholds 199% further from their means (p = 0.0001). Likewise, of 35 EF studies (10220 patients), the thresholds in the 22 positive reports were strongly determined by study means (r = 0.90, p<0.0001). Similarly, in the 19 positives of 20 BNP studies (9725 patients): r = 0.86 (p<0.0001). Second, survival simulations always discovered a "most significant" threshold, even when there was definitely no step change in mortality. With linear increase in risk, the apparently-optimal threshold was always near the sample mean (r = 0.99, p<0.001). LIMITATIONS: This study cannot report the best threshold for any of these variables; instead it explains how common clinical research procedures routinely produce false thresholds. KEY FINDINGS: First, shifting (and/or disappearance) of an apparently-optimal prognostic threshold is strongly determined by studies' average pVO2, EF or BNP. Second, apparently-optimal thresholds always appear, even with no step in prognosis. CONCLUSIONS: Emphatic therapeutic guidance based on thresholds from observational studies may be ill-founded. We should not assume that optimal thresholds, or any thresholds, exist.

Automated 3-dimensional aortic annular assessment by multidetector computed tomography in transcatheter aortic valve implantation.

OBJECTIVES: This study sought to evaluate the accuracy, reproducibility, and predictive value for post-procedural aortic regurgitation (AR) of an automated multidetector computed tomography (MDCT) post-processing imaging software, 3mensio Valves (version 5.1.sp1, 3mensio Medical Imaging BV, the Netherlands), in the assessment of patients undergoing transcatheter aortic valve implantation (TAVI). BACKGROUND: Accurate pre-operative aortic annulus measurements are crucial for patients undergoing TAVI. METHODS: One hundred five patients undergoing MDCT screening before TAVI were evaluated. Aortic annular measurement was compared between automated 3mensio Valves software and manual data post-processing software on a dedicated workstation; we analyzed the discrimination value of annulus measurement for post-procedural AR in 44 recipients of a self-expanding valve. RESULTS: The automated 3mensio Valves software showed good concordance with manual MDCT measurements as demonstrated by Bland-Altman analysis. The automated software provided equally good reproducibility as manual measurement, especially for measurement of aortic annulus area (intraobserver intraclass correlation coefficients 0.98 vs. 0.97, interobserver 0.98 vs. 0.95). In 44 patients after implantation of a self-expanding valve, the valve diameter/CT-measured geometric mean annulus diameter ratio by automated 3mensio Valves software showed moderate and better discrimination ability in predicting post-procedural AR compared with manual measurement (p = 0.12, area under the curve 0.77, 95% confidence interval: 0.63 to 0.91, area under the curve 0.68, 95% confidence interval: 0.50 to 0.86, respectively). CONCLUSIONS: The automated 3mensio Valves software demonstrated reliable, reproducible aortic annulus measurement and better predictive value for post-procedural AR, suggesting important clinical implications for pre-operative assessment of patients undergoing TAVI.