Clinical risk prediction model for 30-day all-cause re-hospitalisation or mortality in patients hospitalised with heart failure.

BACKGROUND: This study aimed to develop a risk prediction model (AUS-HF model) for 30-day all-cause re-hospitalisation or death among patients admitted with acute heart failure (HF) to inform follow-up after hospitalisation. The model uses routinely collected measures at point of care. METHODS: We analyzed pooled individual-level data from two cohort studies on acute HF patients followed for 30-days after discharge in 17 hospitals in Victoria, Australia (2014-2017). A set of 58 candidate predictors, commonly recorded in electronic medical records (EMR) including demographic, medical and social measures were considered. We used backward stepwise selection and LASSO for model development, bootstrap for internal validation, C-statistic for discrimination, and calibration slopes and plots for model calibration. RESULTS: The analysis included 1380 patients, 42.1% female, median age 78.7 years (interquartile range = 16.2), 60.0% experienced previous hospitalisation for HF and 333 (24.1%) were re-hospitalised or died within 30 days post-discharge. The final risk model included 10 variables (admission: eGFR, and prescription of anticoagulants and thiazide diuretics; discharge: length of stay>3 days, systolic BP, heart rate, sodium level (<135 mmol/L), >10 prescribed medications, prescription of angiotensin converting enzyme inhibitors or angiotensin receptor blockers, and anticoagulants prescription. The discrimination of the model was moderate (C-statistic = 0.684, 95%CI 0.653, 0.716; optimism estimate = 0.062) with good calibration. CONCLUSIONS: The AUS-HF model incorporating routinely collected point-of-care data from EMRs enables real-time risk estimation and can be easily implemented by clinicians. It can predict with moderate accuracy risk of 30-day hospitalisation or mortality and inform decisions around the intensity of follow-up after hospital discharge.

The Heart Failure with Preserved Ejection Fraction Conundrum-Redefining the Problem and Finding Common Ground?

PURPOSE OF REVIEW: Heart failure with preserved ejection fraction (HFpEF) or diastolic heart failure (DHF) makes up more than half of all congestive heart failure presentations (CHF). With an ageing population, the case load and the financial burden is projected to increase, even to epidemic proportions. CHF hospitalizations add too much of the financial and infrastructure strain. Unlike systolic heart failure (SHF), much is still either uncertain or unknown. Specifically, in epidemiology, the disease burden is established; however, risk factors and pathophysiological associations are less clear; diagnostic tools are based on rigid parameters without the ability to accurately monitor treatments effects and disease progression; finally, therapeutics are similar to SHF but without prognostic data for efficacy. RECENT FINDINGS: The last several years have seen guidelines changing to account for greater epidemiological observations. Most of these remain general observation of shortness of breath symptom matched to static echocardiographic parameters. The introduction of exercise diastolic stress test has been welcome and warrants greater focus. HFpEF is likely to see new thinking in the coming decades. This review provides some of perspective on this topic.

Confirming a beneficial effect of the six-minute walk test on exercise confidence in patients with heart failure.

BACKGROUND: Low confidence to exercise is a barrier to engaging in exercise in heart failure patients. Participating in low to moderate intensity exercise, such as the six-minute walk test, may increase exercise confidence. AIM: To compare the effects of a six-minute walk test with an educational control condition on exercise confidence in heart failure patients. METHODS: This was a prospective, quasi-experimental design whereby consecutive adult patients attending an out-patient heart failure clinic completed the Exercise Confidence Scale prior to and following involvement in the six-minute walk test or an educational control condition. RESULTS: Using a matched pairs, mixed model design (n=60; 87% male; Mage=58.87±13.16), we identified a significantly greater improvement in Total exercise confidence (F(1,54)=4.63, p=0.036, partial η2=0.079) and Running confidence (F(1,57)=4.21, p=0. 045, partial η2=0.069) following the six-minute walk test compared to the educational control condition. These benefits were also observed after adjustment for age, gender, functional class and depression. CONCLUSION: Heart failure patients who completed a six-minute walk test reported greater improvement in exercise confidence than those who read an educational booklet for 10 min. The findings suggest that the six-minute walk test may be used as a clinical tool to improve exercise confidence. Future research should test these results under randomized conditions and examine whether improvements in exercise confidence translate to greater engagement in exercise behavior.

Self-Care Interventions That Reduce Hospital Readmissions in Patients With Heart Failure; Towards the Identification of Change Agents.

Unplanned hospital readmissions are the most important, preventable cost in heart failure (HF) health economics. Current professional guidelines recommend that patient self-care is an important means by which to reduce this burden. Patients with HF should be engaged in their care such as by detecting, monitoring, and managing their symptoms. A variety of educational and behavioural interventions have been designed and implemented by health care providers to encourage and support patient self-care. Meta-analyses support the use of self-care interventions to improve patient self-care and reduce hospital readmissions; however, efficacy is variable. The aim of this review was to explore methods to achieve greater clarity and consistency in the development and reporting of self-care interventions to enable 'change agents' to be identified. We conclude that advancement in this field requires more explicit integration and reporting on the behaviour change theories that inform the design of self-care interventions and the selection of behaviour change techniques. The systematic application of validated checklists, such as the Theory Coding Scheme and the CALO-RE taxonomy, will improve the systematic testing and refinement of interventions to enable 'change agent/s' to be identified and optimised.

Low psychological resilience is associated with depression in patients with cardiovascular disease.

BACKGROUND: Psychological resilience is associated with an improved capacity to cope with chronic health challenges such as cardiovascular disease. AIMS: The aim of this cross-sectional study was to examine the relationship between psychological resilience and symptoms of depression in a non-acute cardiac outpatient population. METHODS: A total of 419 adult cardiac outpatients (288 men; mean±SD age 66.26±14.04 years) attending cardiovascular clinics completed the Sense of Coherence (SOC13) scale as a measure of psychological resilience and the Cardiac Depression Scale (CDS26) prior to their consultation. RESULTS: The total SOC13 score (mean±SD 64.02±14.24, range 19-91) was within the moderate range. Older patients (⩾65 years) were significantly more resilient than those aged <65 ( p<0.01). Psychological resilience (SOC13) was negatively correlated with depression (CDS26) ( r=-0.79; p<0.001) and inversely associated with affective, cognitive and somatic symptoms of depression. Psychological resilience, particularly meaningfulness, accounted for more of the variance in affective features of depression than for somatic features. CONCLUSION: These findings show that low psychological resilience was related to depression in this cohort of cardiac outpatients, particularly affective symptoms such as anhedonia and hopelessness. The SOC13 scale offers a complementary measure of psychological status that could be used to monitor, and possibly predict, patient coping and response to treatment throughout the cardiovascular disease trajectory.

A novel ligand of calcitonin receptor reveals a potential new sensor that modulates programmed cell death.

We have discovered that the accumulation of an anti-calcitonin receptor (anti-CTR) antibody conjugated to a fluorophore (mAb2C4:AF568) provides a robust signal for cells undergoing apoptotic programmed cell death (PCD). PCD is an absolute requirement for normal development of metazoan organisms. PCD is a hallmark of common diseases such as cardiovascular disease and tissue rejection in graft versus host pathologies, and chemotherapeutics work by increasing PCD. This robust signal or high fluorescent events were verified by confocal microscopy and flow cytometry in several cell lines and a primary culture in which PCD had been induced. In Jurkat cells, GBM-L2 and MG63 cells, the percentage undergoing PCD that were positive for both mAb2C4:AF568 and annexin V ranged between 70 and >90%. In MG63 cells induced for the preapoptotic cell stress response (PACSR), the normal expression of α-tubulin, a key structural component of the cytoskeleton, and accumulation of mAb2C4:AF568 were mutually exclusive. Our data support a model in which CTR is upregulated during PACSR and recycles to the plasma membrane with apoptosis. In cells committed to apoptosis (α-tubulin negative), there is accumulation of the CTR-ligand mAb2C4:AF568 generating a high fluorescent event. The reagent mAb2C4:AF568 effectively identifies a novel event linked to apoptosis.

Northern Territory perspectives on heart failure with comorbidities ­ understanding trial validity and exploring collaborative opportunities to broaden the evidence base.

Congestive Heart Failure (CHF) is an ambulatory care sensitive condition, associated with significant morbidity and mortality, rarely with cure. Outpatient based pharmacological management represents the main and most important aspect of care, and is usually lifelong. This narrative styled opinion review looks at the pharmacological agents recommended in the guidelines in context of the Northern Territory (NT) of Australia. We explore the concept of validity, a term used to describe the basis of standardising a particular trial or study and the population to which it is applicable. We aim to highlight the problems of the current guidelines based approach. We also present alternatives that could utilise the core principles from major trials, while incorporating regional considerations, which could benefit clients living in the NT and remote Australia.

Technology-assisted congestive heart failure care.

The interface between eHealth technologies and disease management in chronic conditions such as chronic heart failure (CHF) has advanced beyond the research domain. The substantial morbidity, mortality, health resource utilization and costs imposed by chronic disease, accompanied by increasing prevalence, complex comorbidities and changing client and health staff demographics, have pushed the boundaries of eHealth to alleviate costs whilst maintaining services. Whilst the intentions are laudable and the technology is appealing, this nonetheless requires careful scrutiny. This review aims to describe this technology and explore the current evidence and measures to enhance its implementation.

Vasoactive role for angiotensin II type 2 receptors in human radial artery.

Angotensin II type 2 receptors are believed to counter the effects of the angiotensin type 1 receptors and there is no data relating to the co-localisation of either receptor in human diseased arteries. We sought to determine whether AT2R counter the effects of AT1R and immunolocalise both receptors to cells in human diseased arteries. Human radial arteries (RA, n=11) were placed in organ bath chambers and preincubated with the AT2R antagonist PD123319 for twenty minutes before an angiotensin II dose response curve. Immunohistochemistry was performed to identify receptors and pathology was quantified by image analysis software. We observed both receptors in human arteries. Angiogenic blood vessels within occluded arteries expressed both receptors. PD123319 impaired angiotensin II mediated vasoconstriction by 20 percent (n=5, p less than 0.05), however in other arteries, PD123319 exacerbated angiotensin II-mediated vasoconstriction by 60 percent (n=6, p less than 0.01), respectively. We conclude that inhibition of AT2R can enhance or reduce angiotensin II-mediated vasoconstriction. These data indicate that the role of AT2R in human diseased arteries is divergent although the AT2R-mediated vasorelaxation prevails.

Evidence-based chronic heart-failure management programmes: reality or myth?

BACKGROUND: Chronic heart-failure management programmes (CHF-MPs) have become part of standard care for patients with chronic heart failure (CHF). OBJECTIVE: To investigate whether programmes had applied evidence-based expert clinical guidelines to optimise patient outcomes. DESIGN: A prospective cross-sectional survey was used to conduct a national audit. SETTING: Community setting of CHF-MPs for patients postdischarge. SAMPLE: All CHF-MPs operating during 2005-2006 (n=55). Also 10-50 consecutive patients from 48 programmes were recruited (n=1157). MAIN OUTCOME MEASURES: (1) Characteristics and interventions used within each CHF-MP; and (2) characteristics of patients enrolled into these programmes. RESULTS: Overall, there was a disproportionate distribution of CHF-MPs across Australia. Only 6.3% of hospitals nationally provided a CHF-MP. A total of 8000 postdischarge CHF patients (median: 126; IQR: 26-260) were managed via CHF-MPs, representing only 20% of the potential national case load. Significantly, 16% of the caseload comprised patients in functional New York Heart Association Class I with no evidence of these patients having had previous echocardiography to confirm a diagnosis of CHF. Heterogeneity of CHF-MPs in applied models of care was evident, with 70% of CHF-MPs offering a hybrid model (a combination of heart-failure outpatient clinics and home visits), 20% conducting home visits and 16% conducting an extended rehabilitation model of care. Less than half (44%) allowed heart-failure nurses to titrate medications. The main medications that were titrated in these programmes were diuretics (n=23, 96%), ß-blockers (n=17, 71%), ACE inhibitors (ACEIs) (n=14, 58%) and spironolactone (n=9, 38%). CONCLUSION: CHF-MPs are being implemented rapidly throughout Australia. However, many of these programmes do not adhere to expert clinical guidelines for the management of patients with CHF. This poor translation of evidence into practice highlights the inconsistency and questions the quality of health-related outcomes for these patients.

Oxygen (O2) kinetics during early recovery from peak exercise in patients with Type 2 diabetes.

AIMS: To examine the oxygen (O(2)) kinetics during early recovery from peak exercise in patients with Type 2 diabetes and to examine whether oxygen O(2) recovery is associated with fasting glucose and HbA(1c) in this population. METHODS: Eighty-nine participants (52 men) aged 51.8 ± 7.1 years (mean ± SD) were divided into three groups: normal weight (BMI ≤ 25.0 kg/m(2)), overweight/obese without diabetes (BMI ≥ 26 kg/m(2)) and overweight/obese with Type 2 diabetes. Participants were assessed for their aerobic power (VO(2peak)) on a cycle ergometer, provided a fasting blood sample and underwent a series of anthropometric measurements. Early recovery period was measured for 60 s from cessation of exercise and expressed as percentage of VO(2peak) (higher percentage represents slower recovery). RESULTS: No significant differences were observed for age between the three study groups. Both the overweight/obese groups without diabetes and with Type 2 diabetes had higher BMI than the normal weight group, with no significant differences between overweight/obese participants without diabetes and those with diabetes. Participants with Type 2 diabetes had lower VO(2peak) than overweight/obese participants without diabetes and normal weight individuals (19.6 ± 4.8, 22.6 ± 5.4 and 25.7 ± 5.3 ml kg(-1) min(-1), respectively, P < 0.004 for overall trends). Participants with Type 2 diabetes also had slower recovery in oxygen O(2) kinetics after exercise, compared with both normal weight and overweight/obese individuals without diabetes (56.5 ± 7.7, 49.2 ± 7.2, 47.7 ± 7.4%, P < 0.004 for overall trends). Multiple regression analysis revealed that percentage of oxygen O(2) recovery was a stronger predictor than VO(2peak), BMI or age for fasting glucose and HbA(1c). CONCLUSIONS: Patients with Type 2 diabetes have lower VO(2peak) and prolonged oxygen O(2) recovery from peak exercise. However, only prolonged oxygen O(2) recovery was associated with fasting glucose and HbA(1c).

The effect of acute exercise on undercarboxylated osteocalcin in obese men.

SUMMARY: The purpose of this study was to examine if the reduction in glucose post-exercise is mediated by undercarboxylated osteocalcin (unOC). Obese men were randomly assigned to do aerobic or power exercises. The change in unOC levels was correlated with the change in glucose levels post-exercise. The reduction in glucose post-acute exercise may be partly related to increased unOC. INTRODUCTION: Osteocalcin (OC) in its undercarboxylated (unOC) form may contribute to the regulation of glucose homeostasis. As exercise reduces serum glucose and improves insulin sensitivity in obese individuals and individuals with type 2 diabetes (T2DM), we hypothesised that this benefit was partly mediated by unOC. METHODS: Twenty-eight middle-aged (52.4 ± 1.2 years, mean ± SEM), obese (BMI = 32.1 ± 0.9 kg m(-2)) men were randomly assigned to do either 45 min of aerobic (cycling at 75% of VO(2peak)) or power (leg press at 75% of one repetition maximum plus jumping sequence) exercises. Blood samples were taken at baseline and up to 2 h post-exercise. RESULTS: At baseline, unOC was negatively correlated with glucose levels (r = -0.53, p = 0.003) and glycosylated haemoglobin (HbA1c) (r = -0.37, p = 0.035). Both aerobic and power exercises reduced serum glucose (from 7.4 ± 1.2 to 5.1 ± 0.5 mmol L(-1), p = 0.01 and 8.5 ± 1.2 to 6.0 ± 0.6 mmol L(-1), p = 0.01, respectively). Aerobic exercise significantly increased OC, unOC and high-molecular-weight adiponectin, while power exercise had a limited effect on OC and unOC. Overall, those with higher baseline glucose and HbA1c had greater reductions in glucose levels after exercise (r = -0.46, p = 0.013 and r = -0.43, p = 0.019, respectively). In a sub-group of obese people with T2DM, the percentage change in unOC levels was correlated with the percentage change in glucose levels post-exercise (r = -0.51, p = 0.038). CONCLUSIONS: This study reports that the reduction in serum glucose post-acute exercise (especially aerobic exercise) may be partly related to increased unOC.

Evidence-based chronic heart failure management programs: reality or myth?

BACKGROUND: Chronic heart failure management programmes (CHF-MPs) have become part of standard care for patients with chronic heart failure (CHF). OBJECTIVE: To investigate whether programmes had applied evidence-based expert clinical guidelines to optimise patient outcomes. DESIGN: Prospective cross-sectional survey was used to conduct a national audit. SETTING: Community setting of CHF-MPs for patients after discharge. SAMPLE: All CHF-MPs operating during 2005-2006 (n = 55). 10-50 consecutive patients from 48 programmes were also recruited (n = 1157). MAIN OUTCOME MEASURES: (1) Characteristics and interventions used within each CHF-MP and (2) characteristics of patients enrolled into these programmes. RESULTS: Overall, there was a disproportionate distribution of CHF-MPs across Australia. Only 6.3% of hospitals nationally provided a CHF-MP. A total of 8000 post-discharge CHF patients (median, 126; IQR, 26-260) were managed via CHF-MPs representing only 20% of the potential national case load. Significantly, 16% of the case load comprised patients in functional New York Heart Association class I with no evidence of these patients having had previous echocardiography to confirm a diagnosis of CHF. Heterogeneity of CHF-MPs in applied models of care was evident with 70% of CHF-MPs offering a hybrid model (a combination of heart failure outpatient clinics and home visits), 20% conducting home visits and 16% an extended rehabilitation model of care. Less than half (44%) allowed heart failure nurses to titrate medications. The main medications that were titrated in these programmes were diuretics (n = 23, 96%), beta-blockers (n = 17, 71%), ACE inhibitors (n = 14, 58%) and spironolactone (n = 9, 38%). CONCLUSION: CHF-MPs are being implemented rapidly throughout Australia. However, many of these programmes do not adhere to expert clinical guidelines for the management of patients with CHF. This poor translation of evidence into practice highlights the inconsistency and questions the quality of health-related outcomes for these patients.

Inflammation, hepatic enzymes and resistance training in individuals with metabolic risk factors.

AIMS: Increases in inflammatory markers, hepatic enzymes and physical inactivity are associated with the development of the metabolic syndrome (MetS). We examined whether inflammatory markers and hepatic enzymes are correlated with traditional risk factors for MetS and studied the effects of resistance training (RT) on these emerging risk factors in individuals with a high number of metabolic risk factors (HiMF, 2.9 +/- 0.8) and those with a low number of metabolic risk factors (LoMF, 0.5 +/- 0.5). METHODS: Twenty-eight men and 27 women aged 50.8 +/- 6.5 years (mean +/- sd) participated in the study. Participants were randomized to four groups, HiMF training (HiMFT), HiMF control (HiMFC), LoMF training (LoMFT) and LoMF control (LoMFC). Before and after 10 weeks of RT [3 days/week, seven exercises, three sets with intensity gradually increased from 40-50% of one repetition maximum (1RM) to 75-85% of 1RM], blood samples were obtained for the measurement of pro-inflammatory cytokines, C-reactive protein (CRP), gamma-glutamyltransferase (GGT) and alanine aminotransferase (ALT). RESULTS: At baseline, HiMF had higher interleukin-6 (33.9%), CRP (57.1%), GGT (45.2%) and ALT (40.6%) levels, compared with LoMF (all P < 0.05). CRP, GGT and ALT correlated with the number of risk factors (r = 0.48, 0.51 and 0.57, respectively, all P < 0.01) and with other anthropometric and clinical measures (r range from 0.26 to 0.60, P < 0.05). RT did not significantly alter inflammatory markers or hepatic enzymes (all P > 0.05). CONCLUSIONS: HiMF was associated with increased inflammatory markers and hepatic enzyme concentrations. RT did not reduce inflammatory markers and hepatic enzymes in individuals with HiMF.

ACE2 and AT4R are present in diseased human blood vessels.

A growing body of evidence suggests that the angiotensin II fragments, Ang(1-7) and Ang(3-8), have a vasoactive role, however ACE2, the enzyme that produces Ang(1-7), or AT4R, the receptor that binds Ang (3-8), have yet been simultaneously localised in both normal and diseased human conduit blood vessels. We sought to determine the immunohistochemical distribution of ACE2 and the AT4R in human internal mammary and radial arteries from patients undergoing coronary artery bypass surgery. We found that ACE2 positive cells were abundant in both normal and diseased vessels, being present in neo-intima and in media. ACE2 positive immunoreactivity was not present in the endothelial layer of the conduit vessels, but was clearly evident in small newly formed angiogenic vessels as well as the vaso vasorum. Endothelial AT4R immunoreactivity were rarely observed in either normal and diseased arteries, but AT4R positive cells were observed adjacent to the internal elastic lamine in the internal mammary artery, in the neo-intima of radial arteries, as well as in the media of both internal mammary artery and radial artery. AT4R was abundant in vaso vasorum and within small angiogenic vessels. Both AT4R and ACE2 co-localised with smooth muscle cell alpha actin. This study identifies smooth muscle cell alpha actin positive ACE2 and AT4R in human blood vessels as well as in angiogenic vessels, indicating a possible role for these enzymes in pathological disease.

Calcitonin receptor immunoreactivity associated with specific cell types in diseased radial and internal mammary arteries.

AIMS: To determine and quantify calcitonin receptor (CTR) immunoreactivity associated with specific cell types within, and associated with, the endothelial layers, neo-intima, media and vasa vasorum of diseased radial and internal mammary arteries. METHODS AND RESULTS: Immunohistochemistry and anti-CTR antibodies were used to identify positive cells within remnants of diseased human radial (n = 3) and internal mammary arteries (n = 4) that remained after bypass surgery. Three cell types expressed CTR, including endothelial cells, fibroblast-like cells within the neo-intima, and cellular structures aligned with the smooth muscle cells of the media. Other smaller cells within the surrounding parenchyma of the vasa vasorum of diseased vessels and blood-borne cells were also immunoreactive. Immunoquantification of CTR expression (Intensity x Proportional Area) in the endothelium (P < 0.05), neo-intima (P < 0.02) and media (P < 0.03) established a significant statistical correlation (Students' two-tailed t-test) with the ratio of intimal/media thickness. CONCLUSIONS: Increased immunoreactivity developed using anti-CTR antibodies was associated with specific cell types in the endothelial layers, neo-intima, media and vasa vasorum of diseased regions of radial and internal mammary arteries, in which there was an increased intimal/media ratio. Furthermore, CTR+, blood-borne cells present in the vessels of diseased regions suggest recruitment into these surrounding tissues.

Thiazolidinediones and congestive heart failure--exacerbation or new onset of left ventricular dysfunction?

BACKGROUND: Patients with diabetes mellitus have a high incidence of coronary heart disease and congestive heart failure (CHF). Thiazolidinediones (TZD) are a new class of pharmacological agents for the treatment of Type 2 diabetes mellitus, which have many beneficial cardiovascular effects. Peripheral oedema and weight gain have been reported in 4.8% of subjects on TZDs alone, with a higher incidence noted in those receiving combination insulin therapy (up to 15%), but there is limited data on the occurrence of CHF. METHODS AND RESULTS: In this paper, we report on six cases of TZD-induced fluid retention with symptoms and signs of peripheral oedema and/or CHF that occurred in subjects attending our diabetic clinic. The predominant finding in all cases was of diastolic dysfunction. All subjects were obese and hypertensive, with 5/6 having the additional risk factor of LVH, 5/6 subjects had microvascular complications, whilst 3/6 were also on insulin therapy. CONCLUSION: We suggest that obese, hypertensive diabetics may benefit from echocardiographic screening prior to commencement of TZDs, as these agents may exacerbate underlying undiagnosed left ventricular diastolic dysfunction.

Recovery from acute coronary syndromes. Hidden snares to resuming normality.

BACKGROUND: Patients with acute coronary syndromes often experience subsequent adjustment difficulties. These are not usually volunteered by the patient yet result in significant morbidity. To optimise quality of life, these 'hidden' problems need to be understood, prevented where possible, uncovered and remedied. OBJECTIVE: To discuss common psychological and social reactions to acute coronary syndromes and the prevention and management of these problems, including the role of rehabilitation programs and the family doctor. DISCUSSION: Adjustment problems can be prevented and successfully managed only if they are understood and elicited by the health professional.

Preoperative assessment of hand circulation by means of Doppler ultrasonography and the modified Allen test.

OBJECTIVE: The aims of this study were as follows: (1) to evaluate Doppler ultrasonography in assessing hand collateral circulation; (2) to define the criteria for an abnormal Doppler ultrasonography dynamic test result; and (3) to validate the modified Allen test. METHODS: The hand circulation of 71 patients scheduled for coronary artery bypass grafting was assessed by means of the Allen test and Doppler ultrasonography. The flow in the superficial palmar branch of the radial artery, the ulnar artery, and the dorsal digital thumb artery with and without radial artery compression were recorded. Flow patterns in the superficial palmar branch of the radial artery, the ulnar artery, and the dorsal digital thumb artery with radial artery compression were categorized into 4 groups: (1) no flow; (2) decreased flow; (3) reversed flow; and (4) increased flow. RESULTS: Among the 71 hands, 4 (5.6%) had an abnormal Allen test result (>10 seconds). Seven (10.6%) of 66 superficial palmar branches of the radial artery, 3 (4.2%) of 71 ulnar arteries, and 2 (2.8%) of 71 dorsal digital thumb arteries showed no flow with radial artery compression, as measured by Doppler ultrasonography. There were significant differences among the 4 groups (superficial palmar branch of the radial artery: F = 7.0, P <.001; ulnar artery: F = 13.1, P <.001; and dorsal digital thumb artery: F = 8.4, P <.001) for the Allen test. Pairwise comparisons showed that when subjected to an Allen test, category 1 patients (no flow) had significantly longer recovery times compared with the other groups (P <.02 in all cases) for the superficial palmar branch of the radial artery, the ulnar artery, and the dorsal digital thumb artery. CONCLUSION: Absence of flow in the dorsal digital thumb artery with radial artery compression is considered an absolute contraindication to radial artery harvesting. An increased recovery time with the modified Allen test predicts absence of flow in the dorsal digital thumb artery in Doppler ultrasonographic flow patterns. This demonstrates the validity of the modified Allen test for primary screening.