Prolonged high-pressure is required for optimal stent deployment as assessed by optical coherence tomography.

AIMS: Optimizing stent deployment is important for both acute- and long-term outcomes. High-pressure balloon inflation is the standard for coronary stent implantation. However, there is no standardized inflation protocol. We hypothesized that prolonged high-pressure balloon inflation until stabilization of inflation pressure is superior to a rapid inflation/deflation sequence for both stent expansion and strut apposition. METHODS AND RESULTS: A high-pressure rapid inflation/deflation sequence was deployed followed by angiography to assure no residual stenosis. Optical coherence tomography (OCT) was then performed followed by prolonged inflation until balloon pressure was stabilized for 30 sec using the same balloon at the same pressure as the rapid sequence. A second OCT run was then done. Thirteen thousand nine hundred thirteen stent struts were evaluated by OCT in 12 patients undergoing successful stenting. Stent expansion improved with prolonged (206 ± 115 sec) vs. rapid (28 ± 17 sec) inflation for both minimal stent diameter (3.0 ± 0.5 vs. 2.75 ± 0.44 mm, P < 0.0001) and area (7.83 ± 2.45 vs. 6.63 ± 1.85 mm(2) , P = 0.0003). The number of malapposed struts decreased (45 ± 41 vs. 88 ± 75, P = 0.005) as did the maximal malapposed strut distance (0.31 ± 0.2 vs. 0.43 ± 0.2 mm, P = 0.0001). Factors related to strut malapposition after rapid inflation included localized asymmetry in 67%, stent underexpansion in 75%, and stent undersizing in 67%. CONCLUSIONS: These data demonstrate that prolonged inflation is superior to a rapid inflation/deflation technique for both stent expansion and strut apposition. We recommend for routine stent deployment a prolonged inflation protocol as described above to optimize stent deployment.

Soybean Knowledge Base (SoyKB): a web resource for soybean translational genomics.

BACKGROUND: Soybean Knowledge Base (SoyKB) is a comprehensive all-inclusive web resource for soybean translational genomics. SoyKB is designed to handle the management and integration of soybean genomics, transcriptomics, proteomics and metabolomics data along with annotation of gene function and biological pathway. It contains information on four entities, namely genes, microRNAs, metabolites and single nucleotide polymorphisms (SNPs). METHODS: SoyKB has many useful tools such as Affymetrix probe ID search, gene family search, multiple gene/metabolite search supporting co-expression analysis, and protein 3D structure viewer as well as download and upload capacity for experimental data and annotations. It has four tiers of registration, which control different levels of access to public and private data. It allows users of certain levels to share their expertise by adding comments to the data. It has a user-friendly web interface together with genome browser and pathway viewer, which display data in an intuitive manner to the soybean researchers, producers and consumers. CONCLUSIONS: SoyKB addresses the increasing need of the soybean research community to have a one-stop-shop functional and translational omics web resource for information retrieval and analysis in a user-friendly way. SoyKB can be publicly accessed at http://soykb.org/.

Potential contribution of open-cell stent design to balloon entrapment and review of techniques to recover.

Balloon entrapment during coronary angioplasty is a rare but potentially disastrous complication of percutaneous coronary intervention (PCI), described during both angioplasty alone, as well as with stents. This report describes the case of an entrapped stent-balloon within an extremely calcified proximal left anterior descending artery (LAD) lesion, and reviews techniques and strategies that can be applied in similar situations. In this case, we suspect the open-cell design of the specific stent used, combined with the high radial force of the calcified lesion, led to a "pincer effect," and entanglement of the balloon material within the stent scaffolding. After exhaustion of all percutaneous options to retrieve the balloon, the patient was ultimately taken for urgent cardiac surgery for extraction of the balloon and vein patch of the LAD.

Renal function and risk stratification of diabetic and nondiabetic patients undergoing evaluation for coronary artery disease.

OBJECTIVES: The aim of this study was to evaluate the impact of renal function by estimated glomerular filtration rate (eGFR) on risk stratification of diabetic and nondiabetic patients undergoing myocardial perfusion imaging (MPI) by single-photon emission computed tomography for suspected ischemia. BACKGROUND: Coronary artery disease is the leading cause of death among diabetic persons; however, diabetic persons are a very heterogeneous group in terms of cardiovascular risk, necessitating further risk stratification. METHODS: Patients (n = 1,747, age 65 +/- 10 years, 37% diabetic) undergoing MPI were followed for cardiac death (CD) for a mean of 2.15 +/- 0.8 years. Chronic kidney disease (CKD) was defined by an eGFR <60 ml/min. RESULTS: In the presence of a normal scan, annual CD rate was 0.9% for those with no diabetes mellitus (DM) and no CKD, 0.5% in the DM alone group, 2.35% in CKD alone, and 2.9% in those with both DM and CKD (p < 0.001). Patients with DM+CKD had a 2.7-fold risk of CD compared with no DM no CKD (p = 0.001) after controlling for age, ejection fraction, history of coronary artery disease, and other risk factors. The risk of CD increased as a function of the presence and severity of perfusion defects, regardless of CKD or DM status. Presence of CKD conferred a several-fold higher risk of CD for the various strata of perfusion defects. Log-rank test for difference in probability of CD was nonsignificant for comparison between patients with no DM no CKD and those with DM alone (p = 0.73) but was significant for comparison between patients with no DM no CKD and patients with CKD alone (p < 0.001) or DM+CKD (p < 0.001). CONCLUSIONS: MPI and eGFR provide valuable risk stratification for diabetic and nondiabetic patients. Diabetic patients without CKD seem to have similar short-term cardiac outcomes compared with nondiabetic patients. Underlying CKD seems to identify a high-risk subgroup of diabetic patients.

Predictive value of myocardial perfusion single-photon emission computed tomography and the impact of renal function on cardiac death.

BACKGROUND: Patients with chronic kidney disease (CKD) have worse cardiovascular outcomes than those without CKD. The prognostic utility of myocardial perfusion single-photon emission CT (MPS) in patients with varying degrees of renal dysfunction and the impact of CKD on cardiac death prediction in patients undergoing MPS have not been investigated. METHODS AND RESULTS: We followed up 1652 consecutive patients who underwent stress MPS (32% exercise, 95% gated) for cardiac death for a mean of 2.15+/-0.8 years. MPS defects were defined with a summed stress score (normal summed stress score <4, abnormal summed stress score>or=4). Ischemia was defined as a summed stress score >or=4 plus a summed difference score >or=2, and scar was defined as a summed difference score <2 plus a summed stress score >or=4. Renal function was calculated with the Modified Diet in Renal Disease equation. CKD (estimated glomerular filtration rate <60 mL . min(-1) . 1.73 m(-2)) was present in 36%. Cardiac death increased with worsening levels of perfusion defects across the entire spectrum of renal function. Presence of ischemia was independently predictive of cardiac death, all-cause mortality, and nonfatal myocardial infarction. Patients with normal MPS and CKD had higher unadjusted cardiac death event rates than those with no CKD and normal MPS (2.7% versus 0.8%, P=0.001). Multivariate Cox proportional hazards models revealed that both perfusion defects (hazard ratio 1.90, 95% CI 1.47 to 2.46) and CKD (hazard ratio 1.96, 95% CI 1.29 to 2.95) were independent predictors of cardiac death after accounting for risk factors, left ventricular dysfunction, pharmacological stress, and symptom status. Both MPS and CKD had incremental power for cardiac death prediction over baseline risk factors and left ventricular dysfunction (global chi(2) 207.5 versus 169.3, P<0.0001). CONCLUSIONS: MPS provides effective risk stratification across the entire spectrum of renal function. Renal dysfunction is also an important independent predictor of cardiac death in patients undergoing MPS. Renal function and MPS have additive value in risk stratisfying patients with suspected coronary artery disease. Patients with CKD appear to have a relatively less benign prognosis than those without CKD, even in the presence of a normal scan.

Effectiveness of anemia and chronic kidney disease as predictors for presence and severity of coronary artery disease in patients undergoing stress myocardial perfusion study.

Chronic kidney disease (CKD) and anemia portend a higher risk of cardiac events and mortality. We sought to ascertain whether coronary artery disease (CAD) by myocardial perfusion single-photon emission computed tomography is more common in patients with CKD (glomerular filtration rate < or =60 ml/min/1.73 kg/m(2)) and/or anemia (hemoglobin level < or =13 g/L) and the impact of different degrees of CKD. One thousand five hundred eighty patients (mean age 65 +/- 10 years) underwent gated myocardial perfusion single-photon emission computed tomography and clinical evaluation. Patients were divided into 4 groups (group 1, no anemia/no CKD, n = 800; group 2, anemia/no CKD, n = 195; group 3, CKD/no anemia, n = 332; group 4, anemia/CKD, n = 253). Multivariate logistic regression analysis was undertaken to examine the association of these diagnoses with abnormal myocardial perfusion single-photon emission computed tomogram. Compared with patients with neither diagnosis, an abnormal scan was more common in those with anemia or CKD. Patients with anemia and CKD exhibited more severe CAD (mean summed stress score 6.8 vs 4.7, p <0.01). Established high-risk findings were more prevalent in patients with anemia and/or CKD, including a summed stress score > or =8, transient ischemic dilation, or a left ventricular ejection fraction < or =40% (group 1 28%, group 2 38%, group 3 38%, group 4 48%, all p values <0.01). Patients with moderate CKD demonstrated an increased risk of an abnormal scan (odds ratio 2.66, p <0.0001). After adjustment in multivariate analysis, anemia and CKD each remained predictors for an abnormal scan. The association was stronger in those with the 2 conditions (odds ratio for high-risk scan 1.89, p = 0.0002). In conclusion, in patients with suspected CAD, anemia and CKD are predictors of myocardial perfusion single-photon emission computed tomographic markers for worsened outcomes. The relation was independent of other risk factors, supporting the inclusion of anemia and CKD in global risk assessment for patients with suspected CAD.