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Based on the characteristics of optical absorption gas sensing technology (OA-GST) and spatial heterodyne spectroscopy (SHS), a novel type of visual gas sensing technology (V-GST) can present the invisible gas information in the form of two-dimensional visual fingerprint, which has attracted people's attention. In this paper, we have realized the NO2 detection of V-GST in the laboratory environment for the first time. Experimental results show that: V-GST not only has different interferogram response to different spectra, but also has good response to different concentrations of NO2, which lays a foundation for the application of this technology in gas sensing. And the average classification recognition rate of the system for different band NO2 response data is over 80%, which verifies the effectiveness of the V-GST in gas detection.

Acrylpimaric acid ethylene glycol acrylate was used as the cross-linking agent to prepare rosin-based polymer microspheres through membrane emulsification–microsuspension polymerization. The prepared microspheres were used as the stationary phase in high-performance liquid chromatography for the separation of polycyclic aromatic hydrocarbons (PAHs) and two analogues of alkaloids. Five PAHs (benzene, naphthalene, fluorene, pyrene, and benzo(e)pyrene) were well separated in the rosin-based polymer column with the resolution (Rs) of 6.088 ± 0.006, 5.759 ± 0.017, 7.019 ± 0.020, and 8.584 ± 0.063. A linear relationship was observed for the carbon numbers of PAHs and lnK as obtained with the equation of ln k = 0.22nc – 2.45, R2 = 0.996 . The rosin-based polymer columns were also employed to separate theophylline–caffeine and camptothecin–10-hydroxy-camptothecin, and the good results were obtained with the Rs of 4.617 ± 0.005 and 2.245 ± 0.049, respectively.

In ovarian cancer patients, tumor fibrosis and angiotensin-driven fibrogenic signaling have been shown to inversely correlate with survival. We sought to enhance drug delivery and therapeutic efficacy by remodeling the dense extracellular matrix in two orthotopic human ovarian carcinoma xenograft models. We hypothesized that targeting the angiotensin signaling axis with losartan, an approved angiotensin system inhibitor, could reduce extracellular matrix content and the associated "solid stress," leading to better anticancer therapeutic effect. We report here four translatable findings: (i) losartan treatment enhances the efficacy of paclitaxel-a drug used for ovarian cancer treatment-via normalizing the tumor microenvironment, resulting in improved vessel perfusion and drug delivery (ii) losartan depletes matrix via inducing antifibrotic miRNAs that should be tested as candidate biomarkers of response or resistance to chemotherapy (iii) although losartan therapy alone does not reduce tumor burden, it reduces both the incidence and the amount of ascites formed and (iv) our retrospective analysis revealed that patients receiving angiotensin system inhibitors concurrently with standard treatment for ovarian cancer exhibited 30 mo longer overall survival compared with patients on other antihypertensives. Our findings provide the rationale and supporting data for a clinical trial on combined losartan and chemotherapy in ovarian cancer patients. 116 6 2210 2219

Background Ventilator-associated pneumonia (VAP) is a common nosocomial infection associated with high morbidity due to multidrug-resistant (MDR) pathogens. The purpose of this study was to determine the occurrence of extended-spectrum β-lactamase (ESBL) genes, especially bla CTX-M-15, in Klebsiella pneumoniae (K. pneumoniae)-associated VAP and to investigate the antimicrobial resistance patterns and molecular epidemiological characteristics of K. pneumoniae strains. Materials and methods From January 2013 to December 2015, we retrospectively collected 89 VAP-causing K. pneumoniae isolates from tertiary-care hospitals in China, among which ESBL-producing strains were assessed for antimicrobial susceptibility. Several antibiotic resistance genes of clinical relevance in K. pneumonia isolates producing ESBL were investigated. Polymerase chain reaction (PCR) and DNA sequencing were employed to characterize the genetic contexts of bla CTX-M-15. Conjugative plasmids carrying bla CTX-M-15 were obtained by mating and further subjected to replicon typing. The genetic relatedness of isolates was assessed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. Results All of the 30 ESBL-producing isolates identified displayed MDR phenotype, with bla SHV, bla CTX-M, bla OXA, and bla TEM detected in 21, 21, 1, and 20 isolates, respectively. bla CTX-M-15 was the most prevalent ESBL gene (19/30, 63.33%), and ISEcp1 was detected 48 bp upstream of 15 bla CTX-M-15 genes. Based on S1-PFGE analyses, 25 isolates exhibited different plasmid profiles, ranging from ~70 to 320 kb. The bla CTX-M-15 with bla TEM and qnr genes and the ISEcp1 element from eight isolates were co-transferrable to recipients via conjugation, with IncFIB, IncFIC, and IncFII being the most prevalent replicons. Twenty different PFGE patterns and 11 sequence types were identified, with ST304 being dominant. Conclusion This work reports the emergence of bla CTX-M-15 in K. pneumoniae-induced VAP in China. We showed that IncFIB, IncFIC, and/or IncFII plasmids carrying bla CTX-M-15 with bla TEM, qnr resistance genes, and the ISEcp1 element mediate the local prevalence in K. pneumoniae-associated VAP.

Background: Azacitidine is commonly used in the treatment of relapsed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), but the effectiveness of this monotherapy is still very low. A possible mechanism of resistance to hypomethylating agents (HMAs) is the upregulation of the expression of inhibitory checkpoint receptors and their ligands, making the combination of HMAs and immune checkpoint blockade therapy a rational approach. Although the safety of anti-programmed cell death protein (PD)-1 antibodies for patients with post-allo-HSCT remains a complicated issue, the preliminary clinical result of combining azacitidine with anti-PD-1 antibodies is encouraging; however, the safety and efficacy of this approach need further investigation.Case Presentation: We reported a case of treated secondary (ts)-AML in a patient who received tislelizumab (an anti-PD-1 antibody) in combination with azacitidine. The patient relapsed after allo-HSCT and was previously exposed to HMAs-based therapy. The patient received tislelizumab for compassionate use. After the combination treatment, the patient achieved complete remission with incomplete hematologic recovery, negative minimal residual disease (MRD) by flow cytometry (FCM), and negative Wilms' tumor protein 1 (WT1). However, the patient successively developed serious immune-related adverse events (irAEs) and graft vs. host disease (GVHD) and eventually died from complications of GVHD.Conclusion: To our knowledge, this is the first case to report the combined use of tislelizumab and azacitidine to treat relapsed AML posttransplantation. This report highlights the safety concerns of using an anti-PD-1 antibody in combination with azacitidine after allo-HSCT, especially the risk of GVHD, and provides a basis for future studies.

In this study, an anticalin that could specifically bind paraquat (PQ), a quaternary nitrogen herbicide, as a new set of engineered receptor protein with antibody-like properties was generated to detect PQ concentration. To this end, a native and random library was constructed and engineered to allow in vitro transcription and translation using an Escherichia coli lysate system. Meanwhile, a PQ derivative that carries an active aliphatic carboxylate group at the end of an aliphatic spacer arm was synthesized. Then, this compound was coupled covalently to the carrier protein bovine serum albumin/ovalbumin and amino-functionalized paramagnetic beads. Alternating selection in solution and immobilization in microtiter wells were used to pan mRNA-ribosome-antibody complexes. After several rounds of ribosome display, three variants were selected from a random library of the bilin-binding protein. The variants that could bind complex PQ with high affinity and exhibit IC50 values as low as 14.039 ± 0.970 ng/mL were identified. Moreover, the limits of detection reached 0.083 ± 0.011 ng/mL. Our data suggest that the generation of anticalins may provide a promising alternative to recombinant antibody fragments to create a stable receptor protein against hapten with bioanalytical relevance.

Background: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) following chemotherapy is part of standard treatment protocol for patients with acute myeloid leukemia (AML). FUS-ERG+ AML is rare but has an extremely poor prognosis even with allo-HSCT in remission, possibly due to its a leukemia stem cell (LSC)-driven disease resulting in chemotherapy resistance and a novel therapy is urgently required. It has been reported that FUS-ERG-positive AML expresses CD123, a marker of LSC, in some cases. CD123-targeted CAR T cell (CART123) is promising immunotherapy, but how to improve the complete remission (CR) rate and rescue potential hematopoietic toxicity still need to explore. Case Presentation: We used donor-derived CART123 as part of conditioning regimen for haploidentical HSCT (haplo-HSCT) in a patient with FUS-ERG+ AML who relapsed after allogeneic transplantation within 3 months, resists to multi-agent chemotherapy and donor lymphocyte infusion (DLI) and remained non-remission, aiming to reduce these chemotherapy-resistant blasts and rescue potential hematopoietic toxicity. The blasts in BM were reduced within 2 weeks and coincided with CAR copies expansion after CART123 infusion. The patient achieved full donor chimerism, CR with incomplete blood count recovery, and myeloid implantation. Conclusion: Our results hints that CART123 reduces the chemotherapy-resistant AML blasts for FUS-ERG+ AML without affecting the full donor chimerism and myeloid implantation.

The association between ATP-binding cassette subfamily B member 1 (ABCB1) C3435T and C1236T polymorphisms and the risk for childhood acute lymphoblastic leukemia (ALL) is inconclusive. We conducted a meta-analysis of all published studies to determine the association of ABCB1 C3435T and C1236T polymorphisms and pediatric ALL risk. A systematic retrieval of relevant publications from the PubMed and Web of Science databases was performed. Data were calculated and statistical analysis was performed using STATA version 12.0 software. Metaanalysis results showed no significant association between C3435T polymorphism and pediatric ALL risk (TT vs. CC: odds ratio [OR] = 1.20, 95% confidence interval [CI] = 0.95-1.52; CT vs. CC: OR = 1.00, 95% CI = 0.82-1.23; the dominant model: OR = 1.07, 95% CI = 0.89-1.29; the recessive model: OR = 1.17, 95% CI = 0.84-1.62). Similarly, there was no association found for the C1236T polymorphism (TT vs. CC: OR = 1.18, 95% CI= 0.82-1.70; CT vs. CC: OR = 1.08, 95% CI = 0.80-1.45; the dominant model: OR = 1.10, 95% CI= 0.83-1.46; the recessive model: OR = 0.98, 95% CI = 0.61-1.58). Similar results were observed in the subgroup analyses on ethnicity and Hardy-Weinberg equilibrium. The present meta-analysis found no evidence for ABCB1 C3435T and C1236T polymorphisms as risk factors for pediatric ALL.

Alkaloids are important natural products that exhibit a wide spectrum of pharmacological activities. To efficiently separate and purify them, a rosin-based polymer-bonded silica stationary phase in high-performance liquid chromatography was synthesized via the surface radical polymerization of ethylene glycol maleic rosinate acrylate and methacrylic acid onto functionalized silica. The stationary phases, columns, optimization of chromatographic conditions for alkaloids, and thermodynamic behavior of the analytes on the column were fully studied. Under the optimized conditions, the prepared column efficiently purified natural camptothecine, caffeine, and evodiamine with the corresponding purities of 92, 96, and 97%. With this work, we have developed an efficient approach to isolate alkaloids and promoted the research on rosin-based materials in biomedicine and analytical chemistry.

A lightweight dexterous robotic hand named BITJOCKO with twenty degrees of freedom is presented in this paper. Each knuckle of the hand is equipped with an individually controlled servomotor to enable both-direction bending movements in the range of $0^{\circ}- 100^{\circ}$. The specially designed worm-gear of the drive system not only enlarge the torque of the motor shaft but also equip it with special ability when holding items. Each servomotor is connected with a worm gear. Compare to other forms of a driving system like direct-drive joint, bevel gear joint and harmonic joint. Such characteristics of the worm gears enable the dexterous hand to keep its pose even when the motor forces are turned off after seizing objects. That means this hand is capable of holding weight with considerable self-locking torque. The total weight of BITJOCKO is only 1.1 kilograms. The mechanical design and the philosophy behind is illustrated in detail.

To understand the effects of the eIF-5A gene in response to abiotic stress, the 909 bp full-length cDNA of eIF-5A, including a 480 bp open reading frame encoding 159 amino-acid (aa) residues, was isolated from the leaf of herbal plant (Apocynum venetum) by rapid-amplification of cDNA ends. The deduced molecular weight of the encoding protein was 17.48 kDa with a theoretical pI of 5.61 and predicted no signal peptide. Real-time polymerase chain reaction analysis revealed that AveIF-5A gene expression was induced by cold, salt and drought stress. To determine the biological function of this gene, recombinant plasmids expressing AveIF-5A and AveIF-5A1 (86–156 aa truncated polypeptide) were used to transform Escherichia coli. The analysis of the growth curves of recombinant E. coli revealed that AveIF-5A and AveIF-5A1 improved the resistance of transformed E. coli to low-temperature, drought and salt stress. These results could provide experimental evidence of the function of the AveIF-5A gene as a valuable gene resource in plant resistance-breeding.

In this work, camptothecin (CPT) molecularly imprinted polymer (MIP) microspheres were prepared via membrane emulsification-suspension polymerization using ethylene glycol maleic rosinate acrylate as a crosslinker, acrylic acid as a functional monomer, and CPT as a template molecule. The MIPs were characterized by scanning electron microscopy, laser granulometry, nitrogen sorption porosimetry, and thermogravimetric analysis. The results indicated that the MIPs had a regular spherical shape with porous surfaces and particle sizes mainly ranging from 3 to 5 μm. The surface areas of the MIPs and non-molecularly imprinted polymer (NIP) microspheres were 89.44 and 86.91 m2 g−1, respectively, and their respective average pore sizes were 11.42 and 10.84 nm. Furthermore, the MIPs and NIPs exhibited excellent thermal stabilities. The HPLC columns prepared with the MIPs and NIPs as the chromatographic stationary phase showed good fluidity. The effect of the MIP column on CPT was evaluated with HPLC, and the selectivity and separation performance of the MIP and NIP columns for CPT and 10-hydroxycamptothecin were evaluated. The chromatographic thermodynamics and separation mechanism were also studied. Finally, the MIP column was successfully applied to the separation and purification of CPT from an extract of Camptotheca acuminata fruit, and the reusability of the MIP column was also investigated.

In patients with hypertension, heart failure, or coronary artery disease (CAD), obese patients have been shown to have a lower cardiac event rate compared with normal weight counterparts. This phenomenon has been termed the "obesity paradox." We sought to determine whether the obesity paradox exists in a cohort of patients referred for stress echocardiography. We evaluated 4,103 patients with suspected CAD (58 ± 13 years; 42% men) undergoing stress echocardiography (52% exercise and 47% dobutamine). Patients were divided into 3 groups on the basis of body mass index (BMI): 18.5 to 24.9, 25 to 29.9, and30 kg/m(2). During the follow-up of 8.2 ± 3.6 years, there were 683 deaths (17%). Myocardial ischemia was present in 21% of the population. Myocardial ischemia was more prevalent in patients with a BMI of 18.5 to 24.9 kg/m(2) (26%) than those with a BMI of 25 to 29.9 kg/m(2) (21%) and30 kg/m(2) (18%). Patients with a BMI of30 kg/m(2) had the lowest death rate (1.2%/year) compared with those with a BMI of 25 to 29.9 kg/m(2) (1.75%/year) and 18.5 to 24.9 kg/m(2) (2.9%/year; p0.001). After adjusting for significant clinical variables including exercise capacity, patients with higher BMI (30 kg/m(2) and 25 to 29.9 kg/m(2)) had less risk of mortality compared with those with a BMI of 18.5 to 24.9 kg/m(2) (hazard ratio 0.58, 95% confidence interval 0.47 to 0.72, p0.0001 and hazard ratio 0.69, 95% confidence interval 0.57 to 0.82, p0.0001, respectively). In conclusion, higher survival rate in patients with higher BMI as previously described in patients with hypertension, heart failure, and CAD extends to patients with suspected CAD referred for stress echocardiography, independent of exercise capacity.

The purpose of this study was to evaluate the prognostic value of stress echocardiography in patients with angiographically significant coronary artery disease (CAD). Two hundred sixty patients (mean age 63 ± 10 years, 58% men) who underwent stress echocardiography (41% treadmill, 59% dobutamine) and coronary angiography within 3 months and without intervening coronary revascularization were evaluated. All patients had significant CAD as defined by coronary stenosis ≥70% in major epicardial vessels or branches (45% had single-vessel disease, and 55% had multivessel disease). The left ventricle was divided into 16 segments and scored on a 5-point scale of wall motion. Patients with abnormal results on stress echocardiography were defined as those with stress-induced ischemia (increase in wall motion score of ≥1 grade). Follow-up (3.1 ± 1.2 years) for nonfatal myocardial infarction (n = 23) and cardiac death (n = 6) was obtained. In patients with angiographically significant CAD, stress echocardiography effectively risk stratified normal (no ischemia, n = 91) in contrast to abnormal (ischemia, n = 169) groups for cardiac events (event rate 1.0%/year vs 4.9%/year, p = 0.01). Multivariate logistic regression analysis identified multivessel CAD (hazard ratio 2.53, 95% confidence interval 1.16 to 5.51, p = 0.02) and number of segments in which ischemia was present (hazard ratio 4.31, 95% confidence interval 1.29 to 14.38, p = 0.01) as predictors of cardiac events. A Cox proportional-hazards model for cardiac events showed small, significant incremental value of stress echocardiography over coronary angiography (p = 0.02) and the highest global chi-square value for both (p = 0.004). In conclusion, in patients with angiographically significant CAD, (1) normal results on stress echocardiography conferred a benign prognosis (event rate 1.0%/year), and (2) stress echocardiographic results (no ischemia vs ischemia) added incremental prognostic value to coronary angiographic results, and (3) stress echocardiography and coronary angiography together provided additive prognostic value, with the highest global chi-square value.

The use of stress echocardiography has undergone considerable evolution in the past 3 decades. Although stress echocardiography was first introduced as a noninvasive diagnostic tool for determining the presence or absence of coronary artery disease (CAD), it later served a prognostic role as well. The importance of stress echocardiography in risk stratification and prognosis is substantially undervalued by clinicians. The identification of patients at risk for future cardiac events has become a primary objective in noninvasive evaluation of patients with suspected or known CAD. In particular, the ability of stress echocardiography to identify patients at low (1%), intermediate (1%-5%), or high (5%) risk for future cardiac events is essential to decision making in patient management. Moreover, previous studies have conclusively demonstrated the incremental prognostic value of stress echocardiography over clinical and treadmill exercise data in predicting future cardiac events. This article presents a primarily single-center experience of retrospective and observational studies that address the current role of stress echocardiography and summarize its use for risk stratification, prognosis, and determining clinical outcomes, as well as cost-effective integration of such information in patient management decision making.

Beta-blockers were documented to reduce reinfarction rate more than 3 decades ago and subsequently touted as being cardioprotective for a broad spectrum of cardiovascular indications such as hypertension, diabetes, angina, atrial fibrillation as well as perioperatively in patients undergoing surgery. However, despite lowering blood pressure, beta-blockers have never shown to reduce morbidity and mortality in uncomplicated hypertension. Also, beta-blockers do not prevent heart failure in hypertension any better than any other antihypertensive drug class. Beta-blockers have been shown to increase the risk on new onset diabetes. When compared with nondiuretic antihypertensive drugs, beta-blockers increase all-cause mortality by 8% and stroke by 30% in patients with new onset diabetes. Beta-blockers are useful for rate control in patients with chronic atrial fibrillation but do not help restore sinus rhythm or have antifibrillatory effects in the atria. Beta-blockers provide symptomatic relief in patients with chronic stable angina but do not reduce the risk of myocardial infarction. Adverse effects of beta-blockers are common including fatigue, dizziness, depression and sexual dysfunction. However, beta-blockers remain a cornerstone in the management of patients having suffered a myocardial infarction and for patients with heart failure. Thus, recent evidence argues against universal cardioprotective properties of beta-blockers but attest to their usefulness for specific cardiovascular indications.

Heart failure is an emerging worldwide epidemic. In the USA alone, there are an estimated 4.8 million Americans with heart failure, 10% of persons aged 70 years or greater and 400,000 new cases annually [1]. Heart failure is the most common diagnosis in hospitalized patients aged 65 years and older. There is an exceedingly high mortality rate associated with heart failure; approximately 50% of patients diagnosed with heart failure will be dead within 5 years. As the population ages, with more cardiac patients living longer with their disease, the opportunity for developing heart failure increases. The economic costs of heart failure are substantial with an estimated US$23.2 billion society costs per year in the USA. Coronary artery disease (CAD) is the most common cause of left ventricular (LV) systolic dysfunction leading to heart failure [2]. It was previously thought that loss of myocardial contractility after myocardial infarction was caused by the destruction of myocardium and the development of irreversible scarring. With the subsequent development of coronary artery bypass grafting (CABG), clinical observations showed that in some individuals, the function of hypo or akinetic segments could improve following revascularization [3]. The contractile regional dysfunction seen in patients may be either transient (stunning) or prolonged (hibernation). In reality, the spectrum of myocardial dysfunction is probably a continuum extending from myocardial ischemia to programmed cell death and apoptosis. A proportion of patients with heart failure will confer viability by symptomatic angina or ischemia demonstrated by myocardial perfusion imaging [4]. However, most patients with LV systolic dysfunction due to CAD have a heterogeneous mixture of stunned, hibernating and scarred myocardium in various proportions. Given many considerations, it is clear that patients with heart failure due to CAD should pursue treatment options to prevent future coronary events. These therapies include treatment of heart failure, myocardial ischemia, and myocardial stunning and hibernation. Standard treatment of patients with heart failure due to LV systolic dysfunction include angiotensin-converting enzyme (ACE) inhibitors, angiotensinreceptor blockers, β-blockers and aldosterone antagonists [5–8]. Many cardiologists, and some guidelines [9], recommend evaluating patients with CAD and heart failure to identify patients suitable for coronary revascularization, although this strategy is not evidence based. It is often believed that the presence of viable but dysfunctional myocardium is an indication for revascularization, although very few patients with heart failure undergo viability testing.

ObjectivesThe purpose of this study was to evaluate the role of diastolic dysfunction as measured by left atrial (LA) size in patients undergoing stress echocardiography (SE).BackgroundLeft atrial size is a surrogate marker of diastolic function. However, its prognostic value in patients referred for SE is not well defined.MethodsWe evaluated 2,705 patients (60 ± 13 years, 47% men) undergoing SE (56% dobutamine). Patients with significant mitral valve disease (mitral stenosis or ≥ moderate mitral regurgitation) were excluded. Enlarged LA was defined as a LA size indexed to body surface area ≥2.4 cm/m2. Follow-up (mean 2.7 ± 1.0 years) for nonfatal myocardial infarction or cardiac death (n = 122) was obtained.ResultsA dilated LA was able to further risk-stratify both the normal and abnormal SE groups. In the presence of a dilated LA, an abnormal SE portends a worse prognosis compared with patients with normal LA size. Cox proportional modeling showed that a dilated LA added incremental value over traditional risk factors, stress electrocardiographic, rest echocardiographic, and SE variables for the prediction of hard events (global chi-square increased from 90.4 to 113.1 to 176.1 to 184.4 to 190.5; p < 0.05 all groups). Left atrial size was a significant predictor of events independent of left ventricular systolic dysfunction and ischemia (relative risk = 1.84, 95% confidence interval 1.19 to 2.85; p = 0.006).ConclusionsIn patients referred for stress echocardiography, LA size provides independent and incremental value over standard risk factors including left ventricular systolic dysfunction and ischemia. Left atrial size is a powerful prognosticator and should be routinely used in the prognostic interpretation of stress echocardiography.

The purpose of this study was to evaluate the role of stress echocardiography in the risk stratification and prognosis of patients with left ventricular (LV) hypertrophy. One thousand two patients (mean age 62 +/- 13 years, 35% men) with LV hypertrophy (defined by LV mass index >115 g/m(2) for men and >95 g/m(2) for women) were evaluated. LV mass was calculated using the linear dimension method, as recommended by the American Society of Echocardiography. The calculation of relative wall thickness was performed using the formula (2 x posterior wall thickness)/LV internal diameter. Concentric and eccentric LV hypertrophy were defined as relative wall thicknesses > or =0.42 and

We sought to evaluate the risk stratification ability and incremental prognostic value of stress echocardiography over historic, clinical, and stress electrocardiographic (ECG) variables, over a wide spectrum of bayesian pretest probabilities of coronary artery disease (CAD).Stress echocardiography is an established technique for the diagnosis of CAD. However, data on incremental prognostic value of stress echocardiography over historic, clinical, and stress ECG variables in patients with known or suggested CAD is limited.We evaluated 3259 patients (60 +/- 13 years, 48% men) undergoing stress echocardiography. Patients were grouped into low (15%), intermediate (15-85%), and high (85%) pretest CAD likelihood subgroups using standard software. The historical, clinical, stress ECG, and stress echocardiographic variables were recorded for the entire cohort. Follow-up (2.7 +/- 1.1 years) for confirmed myocardial infarction (n = 66) and cardiac death (n = 105) was obtained.For the entire cohort, an ischemic stress echocardiography study confers a 5.0 times higher cardiac event rate than the normal stress echocardiography group (4.0% vs 0.8%/y, P.0001). Furthermore, Cox proportional hazard regression model showed incremental prognostic value of stress echocardiography variables over historic, clinical, and stress ECG variables across all pretest probability subgroups (global chi2 increased from 5.1 to 8.5 to 20.1 in the low pretest group, P = .44 and P = .01; from 20.9 to 28.2 to 116 in the intermediate pretest group, P = .47 and P.0001; and from 17.5 to 36.6 to 61.4 in the high pretest group, P.0001 for both groups).A normal stress echocardiography portends a benign prognosis (1% event rate/y) in all pretest probability subgroups and even in patients with high pretest probability and yields incremental prognostic value over historic, clinical, and stress ECG variables across all pretest probability subgroups. The best incremental value is, however, in the intermediate pretest probability subgroup.

OBJECTIVE The purpose of this study was to evaluate the role of stress echocardiography in the risk stratification and prognosis of patients with multivessel coronary artery disease (CAD). BACKGROUND Stress echocardiography is an established technique for diagnosis, risk stratification, and prognosis of patients with known or suspected CAD. METHODS We evaluated 409 patients (65 ± 10 years; 63% men) referred for stress echocardiography (45% treadmill, 55% dobutamine), who underwent stress echocardiography and coronary angiography within 3 months. All patients had multivessel CAD as defined by coronary stenosis (≥50% left main or ≥70% in two or more major epicardial vessels or branches). The left ventricle was divided into 16 segments and was scored on a five-point scale of wall motion. Patients with abnormal results on stress echocardiography were defined as those with stress-induced ischemia (increase in wall motion score of ≥1 grade). RESULTS Follow-up (3.1 ± 1.3 years) for nonfatal myocardial infarction (n = 35) and cardiac death (n = 25) was obtained. In patients with multivessel CAD, stress echocardiography effectively risk-stratified normal (no ischemia, n = 83) vs. abnormal (ischemia, n = 326) groups for cardiac events (event rate 1.9 vs. 5.4%/year; P

Patients with prior myocardial infarction (MI) are at increased risk of subsequent cardiac events (MI or cardiac death). The incremental prognostic value and warranty time of a normal stress echocardiogram in this high-risk population is not well defined.We evaluated 251 consecutive patients (62 +/- 11 years; 64% males) with remote history of MI (6 weeks) undergoing stress echocardiography (83% dobutamine). Ischemia was defined as a new reversible wall motion abnormality and/or biphasic response. Follow-up for up to 4 years (mean 2.9 +/- 1.0 years) for confirmed MI (n = 7) and cardiac death (n = 15) were obtained.Stress echocardiography effectively risk stratified patients into normal versus abnormal subgroups (Event rate 0.8% per year vs 4.2% per year; P = 0.01; RR = 5.6, 95% CI = 1.3-24.7). In patients with a normal stress echocardiogram, the event rate at the end of 6, 12, and 18 months were1% per year. After 18 months the event rate in patients with a normal stress echocardiogram increased greatly (1% per year). Stress echocardiography yields incremental prognostic value over clinical and stress electrocardiographic variables (Global chi-square increased from 12.4 to 25 to 31.1, P0.0001 both groups).Stress echocardiography yields appropriate risk stratification and prognosis and provides incremental prognostic value over clinical and stress electrocardiographic variables even in patients with prior MI. A normal stress echocardiogram portends a benign prognosis (1% event rate/year) for up to 18 months.

The role of heart rate (HR) reserve (HRR) in the risk stratification of patients who undergo dobutamine stress echocardiography is not well defined. This study evaluated 1,323 patients (mean age 63 +/- 13 years, 47% men) who underwent dobutamine stress echocardiography. Abnormal stress echocardiographic results were defined as those with stress-induced ischemia. HRR was defined as [(peak HR - HR at rest)/(220 - age - HR at rest)] x 100, with HRR70% defined as low. Follow-up data (2.7 +/- 1.1 years) for confirmed myocardial infarction (n = 16) and cardiac death (n = 58) were obtained. HRR risk stratified patients into normal and abnormal subgroups (event rate 1.1%/year vs 4.2%/year, p0.0001) and further risk stratified patients into normal (adjusted HR 1 [reference] vs 2.88, p = 0.04) and abnormal (adjusted HR 4.17 vs 10.09, p0.0001) stress echocardiography groups. Low HRR (relative risk [RR] 2.15, 95% confidence interval [CI] 1.23 to 4.01, p = 0.013) was an independent predictor of cardiac event even after controlling for standard cardiovascular risk factors, other stress electrocardiographic variables, and stress echocardiographic variables. Low HRR (chi-square 32) was superior to 85% maximum predicted HR (MPHR; chi-square 18) and provided incremental value over stress echocardiography and 85% MPHR (global chi-square increased from 48.3 to 54 to 61.3, p0.0001) in a model consisting of stress echocardiography, MPHR, and HRR. In conclusion, HRR can further risk stratify patients who undergo dobutamine stress echocardiography and provides independent and incremental prognostic value over standard cardiovascular risk factors and also independent of echocardiographic myocardial ischemia and left ventricular dysfunction and is superior to 85% MPHR. In the setting of low HRR, normal stress echocardiographic results are prognostically less benign, whereas abnormal stress echocardiographic results are prognostically more malignant.

The noninvasive assessment of myocardial viability has proved clinically useful for distinguishing hibernating and/or stunned myocardium from irreversibly injured myocardium in patients with chronic ischemic heart disease or recent myocardial infarction, with marked regional and/or global left ventricular (LV) dysfunction. Noninvasive techniques utilized for the detection of viability in asynergic myocardial regions include positron emission tomographic imaging of residual metabolic activity, single photon emission tomography (SPECT) of radioisotope uptake with thallium-201, low-dose dobutamine echocardiography assessment of inotropic reserve and myocardial contrast echocardiography for evaluation of microvascular integrity. Of these techniques, dobutamine stress echocardiography is a safe, widely available and relatively inexpensive modality for the identification of myocardial viability for risk stratification and prognosis. Low-dose dobutamine response can accurately predict improvement of dysfunctional yet viable myocardial regions, and thus identify a subset of patients whose LV function will improve following successful coronary revascularization.

Background: Myocardial perfusion single-photon emission computed tomography (SPECT) permits assessment of stress perfusion and resting left ventricular (LV) function. Quantitative analysis of perfusion patterns among patients with LV dysfunction offers an opportunity for developing criteria to differentiate ischemic from nonischemic cardiomyopathy. Hypothesis: Quantitative assessment of SPECT may allow differentiation between ischemic and nonischemic cardiomyopathy. Methods: We evaluated 144 patients with LV ejection fraction ≤40%, divided into 63 patients with nonischemic and 81 with ischemic cardiomyopathy. Mean relative myocardial counts were obtained for regions drawn over defect and normal zones on rest and stress polar perfusion maps. Results: Multivariate logistic regression analysis of significant univariate SPECT predictors of ischemic cardiomyopathy revealed that the stress defect severity ratio (SDSR) was the best predictor of ischemic cardiomyopathy (p < 0.0001). By receiver operator characteristic (ROC) curve analysis, an SDSR of ≤ 45% optimized prediction of ischemic cardiomyopathy (sensitivity 81%, specificity 96%). An SDSR of ≤ 45% occurred in 65 of 81 (80%) patients with ischemic cardiomyopathy, but in only 3 of the 63 (4%) patients with nonischemic cardiomyopathy (p < 0.0001). Applying the ≤45% SDSR threshold to a prospective group of 89 patients yielded a somewhat lower sensitivity (60%), but retained high specificity (91%) for identifying ischemic cardiomyopathy (p = NS vs. retrospective group). Conclusions: Presence of a severe and extensive stress perfusion defect is a hallmark of ischemic cardiomyopathy. By contrast, a mild stress perfusion defect (SDSR of > 45%) is commonly present among patients with ischemic and non-ischemic cardiomyopathy. An SDSR of ≤45% is a reproducible specific marker for identifying the presence of ischemic cardiomyopathy.

Coronary artery collaterals may have a protective role against myocardial ischemia at rest. However, their role during stress is controversial and poorly defined. We evaluated 212 consecutive patients (57 +/- 16 years; 70% men) who underwent coronary angiography and stress echocardiography within a 3-month period. This cohort of patients (all had significant epicardial coronary artery disease) was divided into 3 groups based on the presence and type of collaterals: group A, no collaterals; group B, collaterals supplied by vessels without flow-limiting stenosis; and group C, collaterals supplied by vessels with flow-limiting stenosis. In all patients, angiographic jeopardy score, ejection fraction, and regional and cumulative wall motion score indexes (WMSIs) at rest and during stress were evaluated. Angiographic jeopardy scores were 2.9, 3.5, and 7.3 for groups A, B, and C, respectively. Baseline ejection fraction was similar between groups A and B (48% vs 46%, p = NS) but lower in group C (31%, p

The prognostic value of stress echocardiography to predict future cardiac events using the extent and severity of wall motion abnormalities is not well defined. The objective of this study was to develop and validate a prognostic model for interpretation of stress echocardiographic studies by using the extent and severity of wall motion abnormalities. We evaluated 1,500 patients (59 +/- 13 years old; 51% men) who underwent stress echocardiography (34% on the treadmill exercise and 66% on dobutamine). Left ventricular regional wall motion was assessed by consensus of 2 experienced echocardiographers. Follow-up periods (mean 2.7 +/- 1.0 years) for confirmed myocardial infarction (n = 31) and cardiac death (n = 44) were identified. Multivariate regression analysis identified 2 independent predictors of cardiac events: the number of left ventricular wall segments with new wall motion abnormalities (an index of the extent of ischemia) and the maximal magnitude of new wall motion abnormalities (an index of the severity of ischemia). The ischemic extent (chi-square 48.7, p0.0001) and maximal severity (chi-square 52.0, p0.0001) were exponentially correlated with an increase in event rate. On the basis of these data, a prognostic model was defined that uses ischemic extent and maximal severity as stress-dependent orthogonal variables. With this 3-dimensional model, the predicted event rate ranged over sevenfold, from a low of 0.9%/year in patients without any wall motion abnormalities to a high of 6.7%/year in patients with extensive and severe wall motion abnormalities. The extent and severity of wall motion abnormalities by stress echocardiography are independent and cumulative predictors of prognosis in patients who have suspected or known ischemic heart disease.

Objectives The purpose of this study was to define appropriate parameters for risk stratification and prognosis in patients undergoing stress echocardiography. Background Stress echocardiography is an established technique for the diagnosis of coronary artery disease. However, current data on risk stratification of patients undergoing stress echocardiography are limited. Methods We evaluated 1,500 patients (59 ± 13 years old; 51% male) undergoing stress echocardiography (34% with treadmill exercise and 66% with dobutamine). Resting left ventricular ejection fraction (EF) and regional wall motion were assessed by the consensus of two echocardiographers. Follow-up (mean 2.7 ± 1.0 years) for confirmed non-fatal myocardial infarction (n = 31) and cardiac death (n = 44) were performed. Results By univariate analysis, both the peak wall motion score index (WMSI) (p Conclusions Stress echocardiography yields prognostic information for risk stratification of patients with known or suspected ischemic heart disease. A normal stress echocardiographic study (peak WMSI = 1.0) confers a benign prognosis (0.9%/year cardiac event rate). Peak WMSI >1.7 and EF ≤45% are independent markers of patients at high risk of an adverse clinical outcome.

Background: Dobutamine-atropine stress echocardiography (DASE) is an established test for the diagnosis and risk stratification of patients with coronary artery disease. Atropine use to attain target heart rate prolongs test time. Hypothesis: The aim of this study was to assess the utility of isometric handgrip exercise (33% maximal voluntary contraction X 4 min) with DASE. Methods: We prospectively evaluated 131 patients undergoing DASE randomized to handgrip exercise or no handgrip. Effect of handgrip exercise on endpoints: time to target heart rate (85% maximum predicted), recovery time, total test time, mean dobutamine and atropine dosage, and the number of ischemic responses were assessed. Effect of current beta-blocker medication use was also evaluated. Results: Heart rate rose more quickly in the handgrip group. At 6-10 min (peak handgrip), mean heart rate rose 51 ± 14 beats/min in the handgrip group compared with 38 ± 18 beats/min in the no handgrip group (p < 0.0001). With handgrip, overall dobutamine study time was reduced by a mean of 4.3 min (16.4 ± 6.9 vs. 20.7 ± 8.4, p = 0.004) in all patients, and by a mean of 5.9 min in patients not on beta-blocker medication (p = 0.001). The handgrip group also had a lower mean dose of dobutamine (25.8 ± 13.5 vs. 32.4 ± 16.4 mg, p = 0.025). The mean atropine dose was also lower (0.2 ± 0.4 vs. 0.4 ± 0.5 mg, p = 0.04). Handgrip exercise, however, did not decrease endpoints in patients on beta-blocker medication. Conclusions: Use of isometric handgrip exercise with DASE decreases time to target heart rate, recovery time, overall study time, and mean dosage of dobutamine and atropine. In patients not on beta-blocker medication, handgrip exercise should be routinely incorporated into all DASE protocols.

Summary Background:In the absence of a prior history of myocardial infarction (MI), left ventricular (LV) dysfunction is commonly due to hypertension, valvular heart disease, or hibernating myocardium. Hypothesis:Since technetium-99m sestamibi gated singlephoton emission computed tomography (SPECT) may be used to determine both stress/rest myocardial perfusion and resting LV function, we attempted to evaluate the ability of gated SPECT imaging to detect occult LV dysfunction. Methods:We evaluated the ability of this technique to detect occult LV dysfunction among 179 patients without history MI and angiographically documented coronary artery disease (CAD). All patients underwent both gated SPECT and cardiac catheterization within a 6-month time period. Left ventricular volume and ejection fraction (EF) values were determined according to a previously validated technique using Simpson’s rule. Normal limit values for LV volumes and EF were derived from a control population of 93 patients with normal coronary angiograms. Results: Based on normal limit-derived criteria, 15% of the CAD study cohort had occult LV dysfunction (>2 standard deviations below gender-specific normal limit means for LVEF). Mean LV end-diastolic volume index (EDVi) was significantly increased (p < 0.05) and LVEF decreased (p < 0.05) in patients with triple-vessel CAD. End-diastolic volume index was also increased in the cohort of patients with both hypertension and LV hypertrophy (LVH) (p < 0.05). However, multivariate logistic regression analysis revealed that only CAD extent, but not hypertension or LVH, was a significant predictor of occult LV dysfunction (p = 0.009). Conclusion: Occult LV dysfunction can be detected in patients with CAD by gating technetium-99m sestamibi SPECT studies, and its presence may signify the presence of extensive CAD.

It is known that Motor Imagery (MI) improves neurorehabilitation in stroke patients while action observation (AO) has the potential to facilitate MI. However, little is known about how to use AO effectively in MI practice. The aim of our study is to compare the effectiveness of synchronous and asynchronous AO in facilitating MI for neurorehabilitation of stroke patients. The participants with hand motor dysfunction following stroke were asked to imagine a specific object insertion and removal task guided by synchronous or asynchronous AO during MI practice. The event-related power decrease (ERD) or event-related power increase (ERS) in sensorimotor rhythms (SMR) of electroencephalographic (EEG) was calculated to evaluate the cortex excitation during MI. The Nine Hole Peg Test (NHPT) and Pinch Strength Test (PST) were used to score functional recovery of the paralyzed hand. The effectiveness of MI was evaluated according to the cortex excitation and the scores of hand functional recovery. The results of ERD in EEG SMR indicate that synchronous AO increases cortex excitation more effectively than asynchronous AO in MI. Meanwhile, higher NHPT and PST scores were achieved after MI training guided by synchronous AO. This reflects that the hand motor function is also improved more significantly by MI practice guided by synchronous AO. Therefore, compared to asynchronous AO, synchronous AO significantly facilitates MI practice and leads to more effective neurorehabilitation of stroke patients.

We reported previously that mean quantified cardiac functional parameters computed by one gated single photon emission computed tomography (SPECT) technique were not significantly altered by common gating errors. However, it is not known to what extent other gated SPECT approaches that are based on different ventricular modeling assumptions are influenced by arrhythmias, nor are the effects of gating errors on visual analyses and their subsequent clinical implications known.Projection data for 50 patients (aged 64 +/- 12 years; 68% men; 76% with myocardial perfusion defects) undergoing technetium-99m sestamibi gated SPECT who were in sinus rhythm during data acquisition were altered to simulate common arrhythmias. To determine quantitative effects, we performed calculations for original control and altered images by Gaussian myocardial detection (Quantitative Gated SPECT [QGS] program) and by wall thickening derived from gated perfusion polar maps (Emory Cardiac Toolbox program). To evaluate visual assessment in control and simulated-arrhythmia tomograms, 2 experienced blinded observers independently interpreted perfusion from polar maps and wall motion and thickening from tomographic cines, using a 4-point scale.Although mean functional parameters were scarcely altered, paired t tests showed ejection fraction fluctuations to be significantly different from control values, causing patients to change between abnormal and normal ejection fraction categories (2% of patients by QGS and 14% by Emory Cardiac Toolbox). Visual examination of QGS polar perfusion and function maps showed changes for 72% of cases, although in only 4% were these considered to have potential clinical consequences. The kappa statistic for visual analysis of concordance between control and arrhythmia readings showed that agreement was "excellent" for perfusion, "good" for motion, and "marginal" for thickening.As with quantitative measurements, thickening is the parameter most prone to error in the presence of arrhythmias. It is important to test data for gating errors to avoid potentially erroneous measurements and visual readings.

The use of myocardial perfusion single photon emission computed tomography (SPECT) has undergone considerable expansion and evolution over the past 2 decades. Although myocardial perfusion imaging was first conceived as a noninvasive diagnostic tool for determining the presence or absence of coronary artery disease, its prognostic value is now well established. Thus, identification of patients at risk for future cardiac events has become a primary objective in the noninvasive evaluation of patients with chest pain syndromes and among patients with known coronary artery disease. In particular, the ability of myocardial perfusion SPECT to identify patients at low (1%), intermediate (1% to 5%) or high (5%) risk for future cardiac events is essential to patient management decisions. Moreover, previous studies have conclusively shown the incremental prognostic value of myocardial perfusion SPECT over clinical and treadmill exercise data in predicting future cardiac events. This report addresses the current role and new developments, with respect to the use of myocardial perfusion imaging, in determining patient risk for cardiac events and the cost-effective integration of such information into patient management decisions.

We describe a case of cocaine-associated acute myocardial infarction managed by cardiac catheterization and intracoronary thrombolysis. Based on this and other reported cases, it appears that an invasive approach to the management of cocaine-associated acute myocardial infarction is advantageous over intravenous thrombolysis. Such a strategy would define the pathophysiology of acute myocardial infarction in the setting of cocaine use and allow mechanical intervention should pharmacologic therapy be unsuccessful.

Dobutamine stress echo (DSE) can be used for risk stratification and prognosis. Hypothesis: The purpose of this study was to evaluate the prognostic value of various types of DSE wall motion responses. We evaluated 2533 patients (64 ± 13 years; 42%male) undergoing DSE grouped by: monophasic/normal

Submaximal stress testing

The ideal provocative maneuver in patients with hypertrophic cardiomyopathy (HCM) is a subject of ongoing investigation. Standing is a fundamental activity of daily life. This study examined acquisition of standing, Valsalva, and post-exercise left ventricular outflow tract gradients in HCM.Rest supine, standing, and post-Valsalva gradients were measured in 98 consecutive patients with HCM who were referred for outpatient echocardiography. In 53 (54%) of the 98 patients, symptom-limited treadmill exercise was also performed, with gradients measured immediately after in the supine position.Fifty-six (57%) of the 98 patients had resting gradient30 mm Hg and would thus be characterized as nonobstructive at rest. In the 98 patients, median gradients were 25 mm Hg at rest (range 0-205 mm Hg), increasing to 44 mm Hg after standing (range 0-309 mm Hg), an increase of 76%, and were again higher after Valsalva, 64 mm Hg (range 0-256 mm Hg) (P.001). In the 53 patients who had gradient assessed after exercise, they were higher still, 100 mm Hg (range 0-256 mm Hg) (P.001). In 29 patients (30%), standing provoked a higher gradient than Valsalva.Although standing increased gradients by 76%, it is not as potent a provocative maneuver as Valsalva or treadmill exercise. Nevertheless, standing is recommended as a physiologic provocative maneuver. In some patients standing may guide therapy; in others, the standing and exercise gradient provide a correct appreciation of the range of physiologically experienced gradients during daily upright activity.

Stress echocardiography is an established technique for diagnosis, risk stratification, and prognosis in patients with known or suspected coronary artery disease. The ability of stress echocardiography to predict clinical outcomes, such as coronary angiography and revascularization, has not been reported previously. The purpose of this study was to evaluate the clinical outcomes of coronary angiography, revascularization, and cardiac events in patients undergoing stress echocardiography.A total of 3121 patients (mean age, 60 + or - 13 years; 48% men) undergoing stress echocardiography (41% treadmill, 59% dobutamine) were assessed. Follow-up (mean, 2.8 + or - 1.1 years) for subsequent coronary angiography, revascularization (percutaneous coronary intervention [PCI] or coronary artery bypass grafting [CABG]), and confirmed hard events (nonfatal myocardial infarction or cardiac death) was obtained.Stress echocardiographic results were normal (peak wall motion score index [pWMSI], 1.0) in 66% and abnormal (pWMSI1.0) in 34% of patients. The pWMSI effectively risk-stratified patients into low-risk (pWMSI, 1.0; 0.8% per year), intermediate-risk (pWMSI, 1.1-1.7; 2.6% per year), and high-risk (pWMSI1.7; 5.5% per year) groups for future cardiac events (P.0001). Early coronary angiography (30 days following stress echocardiography) was performed in only 35 patients (1.7%) with normal stress echocardiographic results and 267 patients (25.5%) with abnormal stress echocardiographic results (P.0001). Late coronary revascularization (2 years following stress echocardiography) occurred in 80 patients (PCI, 2.8%; CABG, 1.1%) with pWMSI values of 1.0, 123 patients (PCI, 13.5%; CABG, 7.3%) with pWMSI values of 1.1 to 1.7, and 102 patients (PCI, 12.7%; CABG, 9.6%) with pWMSI values1.7. Multivariate logistic regression analysis identified pWMSI as a predictor of coronary angiography (relative risk, 2.04; 95% confidence interval, 1.67-2.5), revascularization (relative risk, 1.91; 95% confidence interval, 1.68-2.17), and cardiac events (relative risk, 2.45; 95% confidence interval, 2.09-2.88) (all P values.0001). Patients with markedly abnormal stress echocardiographic results (pWMSI1.7) had a significantly higher cardiac event rate in those who did not undergo coronary revascularization (9.6% per year vs 2.9% per year, P.05).Stress echocardiography is an effective gatekeeper for coronary angiography and revascularization. Stress echocardiographic results influence clinical decision making in higher risk patients with significantly increased referral to coronary angiography and revascularization. Patients with markedly abnormal stress echocardiographic results (pWMSI1.7) were most likely to benefit from coronary revascularization.

The echocardiography literature to date has considered cardiac death and myocardial infarction (MI) as a combined end point. The purposes of the present study were to evaluate the differential prognosis of nonfatal MI versus cardiac death in patients undergoing stress echocardiography and to effectively risk stratify patients using the appropriate combination of functional, ischemic, and infarction data.The authors evaluated 3,259 patients (mean age, 59 +/- 13 years; 48% men) undergoing stress echocardiography. Follow-up (mean, 2.8 +/- 1.1 years) for confirmed nonfatal MI (n = 91) and cardiac death (n = 105) was obtained.Multivariate analysis showed that the strongest predictor of cardiac death was a low ejection fraction (chi(2) = 37.3, P.0001), and the strongest predictor of nonfatal MI was the extent of ischemia (chi(2) = 12.3, P.0001). The relationship between ejection fraction and cardiac death rate was an exponential curve (y = 16.91e(-0.50x); r = -0.99, P.0001). Among patients with ejection fractions30% (the low-risk to intermediate-risk groups), peak wall motion score index (WMSI) was able to further risk stratify patients into a very low risk group (peak WMSI = 1.0; cardiac death rate, 0.26% per year) and a higher risk group (peak WMSI1.7; cardiac death rate, 2.56% per year). However, patients with ejection fractions30% had high cardiac death risk regardless of peak WMSI category.In patients referred for stress echocardiography, the integration of functional information (on the basis of ejection fraction) and ischemic and infarction data (on the basis of WMSI) effectively risk stratifies patients for the outcome-specific end points of cardiac death and nonfatal MI.

BACKGROUND The prognostic value of stress echocardiography (SE) for the diagnosis and risk stratification of coronary artery disease in octogenarians is not well defined. METHODS Follow-up of 5 years (mean 2.9 +/- 1.0 years) for confirmed nonfatal myocardial infarction (n = 17) and cardiac death (n = 37) was obtained in 335 patients, age > or =80 years (mean age 84 +/- 3 years, 44% male), undergoing SE (33% treadmill, 67% dobutamine). Left ventricular (LV) regional wall motion was assessed by a consensus of two echocardiographers and scored as per standard five-point scale, 16-segment model of wall motion analysis. Ischemic LV wall segment was defined as deterioration in the thickening and excursion during stress (increase in wall-motion score index (WMSI) > or =1). RESULTS By univariate analysis, inducible ischemia (chi-square = 38.4, P < 0.001), left ventricular ejection fraction (chi-square = 41.2, P < 0.001), a history of previous myocardial infarction (chi-square = 22.3, P < 0.01), hypertension (chi-square = 33, P < 0.01), and age (chi-square = 27.7, P < 0.01) were significant predictors of future cardiac events. WMSI, an index of inducible ischemia, provided incremental prognostic information when forced into a multivariable model where clinical and rest echocardiography variables were entered first. WMSI effectively stratified octogenarians into low- and high-risk groups (annualized event rates of 1.2 versus 5.8%/year, P < 0.001). CONCLUSIONS Stress echocardiography yields incremental prognostic information in octogenarians and effectively stratifies them into low- and high-risk groups. Precise therapeutic decision making in very elderly patients should incorporate combined clinical and stress echocardiography data.

Objectives The purpose of this study was to evaluate the prognostic value of assessing right ventricular (RV) wall motion abnormalities during stress echocardiography (SE). Background The results of SE are usually interpreted based on wall motion abnormalities of the left ventricle (LV). There is increasing recognition of the prognostic importance of RV. However, RV is still a “forgotten” chamber during routine SE. Methods We evaluated 2,703 patients referred for SE. The LV was evaluated on a 16-segment model 5-point scale and the RV was evaluated on a 3-segment model 5-point scale for wall motion abnormalities. An abnormal RV or LV was defined as one with new (ischemic) or fixed (infarction) wall motion abnormalities. Follow-up (2.7 ± 1.0 years) for confirmed myocardial infarction and cardiac death (n = 122) were obtained. Results An abnormal RV was seen in 112 patients (4%). In the presence of an abnormal LV, patients with abnormal RV had a worse prognosis than those with normal RV. Abnormal RV was a significant predictor of events (adjusted hazard ratio 2.69, 95% confidence interval 1.22 to 5.92; p = 0.014) independent of LV ischemia and ejection fraction. A forward conditional Cox model showed that peak RV wall motion score index provided incremental prognostic value over rest and conventional SE variables (global chi-square increased from 141.4 to 161.8 to 197.0; p Conclusions In patients referred for SE, RV wall motion analysis provides prognostic value independent of LV ischemia and ejection fraction and provides incremental value over rest and conventional SE variables. Right ventricular wall motion analysis should be routinely performed in patients referred for SE for effective risk stratification.

Background: The role of coronary artery collaterals in transient ischemic left ventricular (LV) dilatation (TID) during stress echocardiography is not well defined. Hypothesis: Transient ischemic LV dilatation is a marker for extensive and severe coronary artery disease and represents patients without good collaterals. Methods: We evaluated 212 consecutive patients (57 ± 16 years, 70% male) who had coronary angiography and stress echocardiography within a 3-month period. This cohort of patients was divided into three groups based on type of collaterals: Group A: no collaterals; Group B: collaterals supplied by vessels without flow-limiting stenosis (good collaterals); Group C: collaterals supplied by vessels with flow-limiting stenosis (bad/jeopardized collaterals). In all patients, angiographic jeopardy score (AJS), ejection fraction (EF), and wall motion score index (WMSI) at rest and during stress were evaluated. Transient ischemic LV dilatation was defined as transient increase in the end-systolic dimensions from rest to peak stress. Results: Transient ischemic LV dilatation was present in 42 (20%) patients. Patients with TID had a lower EF, higher AJS, greater number of ischemic segments, and higher peak WMSI. Patients with TID in Group A (no collaterals) and Group C (jeopardized collaterals) had a greater percentage of multivessel disease than those in Group B (good collaterals). Presence of Group A or Group C collaterals was a predictor of TID even after controlling for multivessel disease, rest and peak WMSI, and left anterior descending artery disease. Conclusions: Transient ischemic LV dilatation on stress echocardiography is a marker for extensive and severe coronary artery disease and represents patients with angiographically absent collaterals or those with jeopardized coronary collaterals.

Transient ischemic dilation (TID) of the left ventricle on stress-redistribution thallium-201 scintigraphy is a marker of severe and extensive coronary artery disease (CAD), and associated with an adverse outcome. The significance of transient ischemic dilation during stress echocardiography is not well defined.We assessed 155 patients undergoing stress echocardiography (61% treadmill exercise, 39% dobutamine) with confirmed follow-up (mean 2.8 +/- 1.1 years) for hard events (myocardial infarction, n = 14, and cardiac death, n = 9).Normal limits for TID ratio were developed using data from 39 patients with a low likelihood (5%) of CAD and normal stress echocardiography study findings. The criteria for abnormality was developed based on data from 116 patients who underwent coronary angiography after and within 3 months of an abnormal ischemic stress echocardiography study result. For normal limits, receiver operating characteristic curve analysis showed that abnormal TID ratio values corresponded to left ventricular volume ratios greater than 1.17 (mean +/- 2SD). TID assessment using these criteria for abnormality showed high sensitivity (100%) and moderate specificity (54%) for detection of severe and extensive angiographic CAD. Patients with TID had a greater extent and severity of stress induced wall-motion abnormalities, higher peak wall-motion score index, and worse prognosis than patients without TID.TID during stress echocardiography is a sensitive marker of severe and extensive angiographic CAD and is associated with a high risk of cardiac events (19.7%/y event rate).

The purpose of the study was to define an appropriate parameter for risk stratification and prognosis of patients undergoing stress echocardiography.Among stress echocardiography variables, peak wall-motion score index (WMSI) and ejection fraction (EF) have been shown to be independent and significant predictors of cardiovascular morbidity and mortality. Data on the impact and importance of each parameter in risk stratification and prognosis are limited.We evaluated 1560 patients (59 +/- 13 years; 51% men) undergoing stress echocardiography (36% treadmill, 64% dobutamine). Peak WMSI was derived from the cumulative sum of 16 left ventricular segments divided by sum of visualized segments at peak stress. The ratio of peak WMSI to EF was calculated for the entire cohort. Based on this ratio and using the receiver operating characteristic curve, patients were divided into 3 groups: low- (1.9), intermediate- (1.9-3.1), and high- (3.1) risk subgroups. Follow-up (2.8 +/- 1.1 years) for confirmed myocardial infarction (n = 26) and cardiac death (n = 38) were obtained.Stress echocardiography effectively risk stratified patients into low- (0.7%/y), intermediate- (2.0%/y), and high- (4.4%/y) risk subgroups (P.0001) based on the ratio of peak WMSI to EF. Cox proportional hazard model showed that risk stratification based on the ratio of peak WMSI to EF (global chi2 = 106.05; P.0001) provided incremental value beyond that provided by risk stratification by peak WMSI (global chi2 = 79.23; P.0001) or risk stratification by EF alone (global chi2 = 87.12; P.0001).The ratio of peak WMSI to EF (stress function index) provides best incremental prognostic value and effectively risk stratifies patients into low-, intermediate-, and high-risk subgroups and is better than risk stratification by either peak WMSI or EF alone. The results of stress echocardiography should routinely combine peak WMSI and EF for effective risk stratification.

Stress electrocardiographic (ECG) ST-segment depression is a prognostic marker of adverse cardiac outcomes in coronary artery disease. However, use of concurrent stress echocardiography (ECHO) has lead to concordant and discordant findings on stress electrocardiogram during stress studies. The prognostic value of stress ECHO in the setting of these stress ECG findings has not been previously evaluated. Outcomes of 1,268 patients (60 +/- 12 years old, 48% women) who had normal electrocardiograms and underwent stress ECHO were analyzed. ST-segment depression > or =1.5 mm in 2 contiguous leads on stress electrocardiogram and a wall motion score index of >1 on peak stress echocardiogram were considered abnormal. Events of nonfatal myocardial infarction (n = 18) and cardiac death (n = 32) were analyzed during follow-up (2.8 +/- 0.9 years). In 91 patients (7%) who had abnormal findings on stress electrocardiogram, 38 (41%) had an abnormal finding on stress echocardiogram and 4 had cardiac events (0.6% per year), and all who had a normal finding on stress echocardiogram had no events (n = 53, 59%, p = 0.01). Among 46 events (92%) with a normal finding on stress electrocardiogram, 30 (60%) showed a discordantly abnormal finding on stress echocardiogram (3.2% per year, p