Variation in Arterial Access for Invasive Coronary Procedures in New Zealand: A National Analysis (ANZACS-QI 5).

BACKGROUND: Radial arterial access (RA) and femoral arterial access (FA) rates for invasive coronary angiography (ICA) vary widely internationally. The European Society of Cardiology (ESC) suggests default RA is feasible. We aim to investigate the variation in RA rates across all New Zealand public hospitals. METHODS AND RESULTS: Patient characteristics, procedural details, and inpatient outcome data were collected in the All New Zealand Acute Coronary Syndrome - Quality Improvement (ANZACS-QI) registry on consecutive patients undergoing ICA over five months. Of the 5894 ICAs 81% were via RA. Hospitals averaged 25 - 176 procedures/month (46.5% - 96.4% via RA). Operators averaged 17 procedures/month. Those performing more than 20 ICAs/month had RA rates between 61% - 99%. Of the 75 operators, 69% met the ESC recommendation. After multivariable adjustment higher operator (RR 1.12, CI 1.09 - 1.30) and hospital (RR 1.21, CI 1.15 - 1.28) volume were independent predictors of RA. Those with prior CABG (RR 0.51, CI 0.45 - 0.57), STEMI <12h (RR 0.91, CI 0.87 - 0.96), and female sex (RR 0.96, CI 0.94 - 0.99) were less likely to receive RA. CONCLUSIONS: New Zealand has a high RA rate for ICAs. Rates vary substantially between both operators and centres. Radial arterial was highest amongst the highest volume operators and centres.

Comparison of the management and in-hospital outcomes of acute coronary syndrome patients in Australia and New Zealand: results from the binational SNAPSHOT acute coronary syndrome 2012 audit.

BACKGROUND/AIMS: We aimed to assess differences in patient management, and outcomes, of Australian and New Zealand patients admitted with a suspected or confirmed acute coronary syndrome (ACS). METHODS: We used comprehensive data from the binational Australia and New Zealand ACS 'SNAPSHOT' audit, acquired on individual patients admitted between 00.00 h on 14 May 2012 to 24.00 h on 27 May 2012. RESULTS: There were 4387 patient admissions, 3381 (77%) in Australia and 1006 (23%) in New Zealand; Australian patients were slightly younger (67 vs 69 years, P = 0.0044). Of the 2356 patients with confirmed ACS, Australian patients were at a lower cardiovascular risk with a lower median Global Registry Acute Coronary Events score (147 vs 154 P = 0.0008), but as likely to receive an invasive coronary angiogram (58% vs 54%, P = 0.082), or revascularisation with percutaneous coronary intervention (32% vs 31%, P = 0.92) or coronary artery bypass graft surgery (7.0% vs 5.6%, P = 0.32). Of the 1937 non-segment elevation myocardial infarction/unstable angina pectoris (NSTEMI/UAP) patients, Australian patients had a shorter time to angiography (46 h vs 67 h, P < 0.0001). However, at discharge, Australian NSTEMI/UAP survivors were less likely to receive aspirin (84% vs 89%, P = 0.0079, a second anti-platelet agent (57% vs 63%, P = 0.050) or a beta blocker (67% vs 77%, P = 0.0002). In-hospital death rates were not different (2.7% vs 3.2%, P = 0.55) between Australia and New Zealand. CONCLUSIONS: Overall more similarities were seen, than differences, in the management of suspected or confirmed ACS patients between Australia and New Zealand. However, in several management areas, both countries could improve the service delivery to this high-risk patient group.

Correlation between Cobb angle, spinous process angle (SPA) and apical vertebrae rotation (AVR) on posteroanterior radiographs in adolescent idiopathic scoliosis (AIS).

PURPOSE: To investigate the accuracy and reliability of the Cobb angle, the spinous process angle (SPA), and apical vertebral rotation (AVR) for measuring adolescent idiopathic scoliosis (AIS), and to evaluate the correlations between these measurements. METHODS: A retrospective study of two sets of standing posteroanterior radiographs of patients with AIS was performed. The first set was 59 consecutive patients with AIS with Cobb angles <45° and the second set was 25 patients with Cobb angles >45°. The Cobb angle, SPA and AVR of each curve was measured twice by three observers with varying measurement experience. The mean absolute difference, standard deviation, and intra- and inter-rater reliability coefficients for each measurement were examined. The Pearson correlation coefficients between any two parameters were reported. The association of the Cobb angle with the SPA and AVR was examined using a multiple regression model. RESULTS: The average intra- and inter-observer reliabilities (ICC [2, 1]) of the Cobb angle, SPA, and AVR were 0.99, 0.95, 0.92 and 0.98, 0.88, 0.83, respectively. The correlation coefficients (r) between Cobb angle and SPA, Cobb angle and AVR, and SPA and AVR were 0.93, 0.68, and 0.60, respectively. Using multiple regression, the association between the Cobb angle and SPA combined with AVR was R (2) = 0.90. The resulting regression model was: [Formula: see text]. CONCLUSION: The SPA has high correlation with the Cobb angle. Including the AVR as an additional factor in multiple regression improves the prediction of the Cobb angle.

Chest pain unit (CPU) in the management of low to intermediate risk acute coronary syndrome: a tertiary hospital experience from New Zealand.

BACKGROUND: A chest pain unit (CPU) for management of patients with chest pain at low to intermediate risk for acute coronary syndrome (ACS) appears safe and cost-effective. We report our experience with a CPU from March 2005 to July 2009. METHODS: Prospective audit of patients presenting with chest pain suggestive of ACS but no high risk features and managed using a CPU, which included; serial cardiac troponins and electrocardiography and exercise tolerance test (ETT) if indicated. Outcomes assessed included three-month readmission rate and one year mortality. RESULTS: 2358 patients were managed according to the CPU. Mean age 56 years (17-96 years), 59% men and median stay of 22h (IQR 17-26h). 1933 (82%) were diagnosed as non-cardiac chest pain. 1741 (74%) patients had an ETT. Median time from triage to ETT was 21h (IQR 16-24h). 64 (2.7%) were readmitted within three months. The majority of readmissions, 39 (61%) were for a non-cardiac cause. Twenty patients (1%) were readmitted with ACS. There was no cardiac death after one year of being discharged as non-cardiac chest pain. CONCLUSIONS: This study confirms that a CPU with high usage of predischarge ETT is a safe and effective way of excluding ACS in patients without high risk features in a New Zealand setting.

Activation of KV7 channels stimulates vasodilatation of human placental chorionic plate arteries.

INTRODUCTION: Potassium (K(+)) channels are key regulators of vascular smooth muscle cell (VSMC) excitability. In systemic small arteries, Kv7 channel expression/activity has been noted and a role in vascular tone regulation demonstrated. We aimed to demonstrate functional Kv7 channels in human fetoplacental small arteries. METHODS: Human placental chorionic plate arteries (CPAs) were obtained at term. CPA responses to Kv7 channel modulators was determined by wire myography. Presence of Kv7 channel mRNA (encoded by KCNQ1-5) and protein expression were assessed by RT-PCR and immunohistochemistry/immunofluorescence, respectively. RESULTS: Kv7 channel blockade with linopirdine increased CPA basal tone and AVP-induced contraction. Pre-contracted CPAs (AVP; 80 mM K(+) depolarization solution) exhibited significant relaxation to flupirtine, retigabine, the acrylamide (S)-1, and (S) BMS-204352, differential activators of Kv7.1 - Kv7.5 channels. All CPAs assessed expressed KCNQ1 and KCNQ3-5 mRNA; KCNQ2 was expressed only in a subset of CPAs. Kv7 protein expression was confirmed in intact CPAs and isolated VSMCs. DISCUSSION: Kv7 channels are present and active in fetoplacental vessels, contributing to vascular tone regulation in normal pregnancy. Targeting these channels may represent a therapeutic intervention in pregnancies complicated by increased vascular resistance.

Changes in IGFs in cardiac tissue following myocardial infarction.

We have studied changes in the IGF axis in an ovine model of myocardial infarction (MI), in order to determine the relationship between time-based changes in post-infarct myocardium and IGF levels. IGF localization was studied by immunocytochemistry, production by in situ hybridization, and specific binding by radioligand studies. In surviving tissue, IGF-I peptide localized to cardiomyocytes, with strongest immunostaining at 1 and 2 days post-infarct in the immediate border area adjoining the infarct, where IGF-I mRNA also increased, reaching a maximum at 2 days. Binding of radiolabelled IGF-I in surviving tissue was initially lower than that seen in cardiomyocytes in control myocardium, subsequently increasing to become significantly greater by 6 days post-infarct. In necrotic tissue, IGF-I peptide was still detectable in cardiomyocytes at 0.5 days post-infarct, but had cleared from this area by 1 day, becoming detectable again at 6 days post-infarct in macrophages and fibroblasts infiltrating the repair zone. IGF-I mRNA was not detected in necrotic tissue until 6 days, when probe hybridized to macrophages and fibroblasts. Within the necrotic zone, high levels of radiolabelled IGF-I binding to a combination of receptors and binding proteins were observed in cardiomyocytes in islands of viable tissue located close to the border. Weak immunostaining for IGF-II was observed in cardiomyocytes of the surviving tissue. IGF-II mRNA was not detected in either surviving or necrotic areas. Binding of radiolabelled IGF-II was predominantly to macrophages in both surviving and infarct areas, although as with IGF-I, high levels of binding of radiolabelled IGF-II to a combination of receptors and binding proteins were observed in islands of viable tissue close to the border within the necrotic area. We conclude that, following MI, surviving cardiomyocytes at the infarct border show marked changes in IGF-I localization, production, and specific binding, indicating that the IGF axis is directly involved in post-infarct events, possibly in the maintenance of cardiac function by the induction of hypertrophy and in cell survival by decreasing apoptotic cell death, which has been demonstrated in other cell types.

Cardiac IGF-I manipulation by growth hormone following myocardial infarction.

Evidence of a role for growth hormone (GH) in cardiac structure and function has been derived from studies of patients suffering either GH excess or deficiency, both of which may lead to reduced life expectancy. The role of GH in the ischaemic heart, however, is less than clear. We therefore investigated the effect of 30 days GH treatment in sheep with myocardial infarction. GH treatment significantly increased circulating IGF-I levels (P<0.01), heart weight (P<0.01), and cardiomyocyte cross-sectional area (P<0.001). IGF-I mRNA in peri-infarct cardiac tissue also increased significantly (P<0.05). We conclude that post-infarct GH treatment increases circulating and cardiac IGF-I levels, resulting in significant cardiomyocyte hypertrophy. This increase in cardiomyocyte size appears to correlate with local IGF-I expression rather than plasma IGF-I levels.

Effect of a single bolus of intracoronary basic fibroblast growth factor on perfusion in an ischemic porcine model.

Basic fibroblast growth factor (bFGF) has been shown to induce angiogenesis in various animal models, but the methods of administration used experimentally are not clinically feasible. The objective of this study was to determine whether a single intracoronary bolus injection of bFGF would improve coronary perfusion in a porcine ischemic model that mimics clinical chronic ischemia. A copper coil studded with gold was delivered into the proximal right coronary artery of juvenile Yorkshire pigs and deployed by interventional techniques. After a four-week interval for stenosis maturation, bFGF (100 micrograms) was administered by bolus injection into the left coronary artery in five animals, and vehicle alone was administered in four animals. Angiogenesis and change in right coronary perfusion area were assessed two weeks later by angiography, myocardial contrast echocardiography and immunohistochemistry. The right coronary perfusion area increased significantly after treatment in all but one of the animals that received bFGF but not in any of the controls. Intimal hyperplasia was not induced by bFGF. Capillary density determined histochemically was not different in the two groups. In conclusion, in a porcine ischemic model, bFGF administered by a single bolus intracoronary injection into the contralateral artery improved antegrade perfusion into the ischemic territory although without histological evidence of angiogenesis. This preliminary work merits further investigation.

Cauda equina syndrome in ankylosing spondylitis diagnosed by computed tomography.

A patient is described with longstanding ankylosing spondylitis, who develops radicular pain and neurological abnormalities. The diagnosis was cauda equina syndrome. This diagnosis was made on the basis of the clinical findings and the appearance of the computed tomography scan.

The impact of coronary stenting on immediate procedural complication and long-term clinical restenosis at Waikato Hospital.

AIM: Clinical data on coronary stenting from within New Zealand is scarce and, in particular, the impact of current stent technologies is unknown. We reviewed all angioplasties undertaken at Waikato Hospital over a two year period to determine the clinical effect of coronary stenting on the local population. METHODS: Data from all patients who underwent coronary angioplasty at Waikato Hospital between July 1, 1995 and July 1, 1997 were included. Stents were deployed either to remedy sub-optimal results, or were electively used for saphenous vein grafts or restenotic lesions. Patient follow-up was obtained through a combination of database review, chart search and GP or patient contact. RESULTS: 662 lesions were dilated in 441 patients. 91 lesions were stented, 52.7% for sub-optimal results following balloon angioplasty. 98% of patients were followed up at six months. Whilst procedural success rate was higher in stented patients compared to unstented patients (96.7% vs 87.5% respectively, p=0.009) the in-hospital sub-acute occlusion rate was also increased (6.8% vs 1.9% respectively, p=0.007). At six months, coronary restenosis requiring repeat angioplasty was infrequent (10.9% overall) with no significant difference between the two groups (8.1% vs. 11.2% for stented vs unstented patients respectively, p=NS). CONCLUSIONS: The use of stents appears effective in improving immediate procedural success rates. Despite stented patients being at higher risk initially, their complication and six month clinical restenosis rates were similar.

Early experience of primary angioplasty at Waikato Hospital.

AIM: Acute angioplasty for myocardial infarction without prior thrombolytic therapy (primary angioplasty) has been advocated as the preferred treatment for high risk infarct patients, however data is primarily from highly experienced units. This report describes the first year's experience of primary angioplasty at Waikato Hospital which is a moderate sized institution performing 300 elective angioplasty procedures per year. METHODS: Patients presenting with an acute infarction who were deemed to be either at high risk or who had a contraindication to streptokinase received primary angioplasty. The program operated 24 hours a day, 7 days a week with all procedural and clinical outcomes being prospectively recorded on a database. RESULTS: Fifty one patients underwent primary angioplasty in the first year. Vessel patency was achieved in 86%, with TIMI III flow present in 82%. Time from emergency room arrival to reperfusion averaged 95 minutes and median hospital length of stay was 5 days. Five (10%) patients died while in hospital: those in cardiogenic shock on presentation had a mortality of 33%, and the remainder 5%. CONCLUSIONS: These results suggest that primary angioplasty is logistically feasible in a moderate sized New Zealand hospital with clinical results similar to those reported by the large interventional centers in Europe and the USA.

Survey of Waikato medical practitioners concerning cardiac pacing.

AIM: To assess the knowledge of Waikato medical practitioners concerning cardiac pacing and its indications. METHOD: Anonymous postal questionnaire. The responses received were compared with those of four New Zealand experts on cardiac pacing. RESULTS: 404 questionnaires were administered of which 204 (50%) were returned, (16.3% physicians, 22.7% JRMO's 61% general practitioners). Virtually all had ready access to diagnostic facilities and were satisfied with the service offered. Physicians were more likely to have referred patients and to have had personal experience with pacing. Practical matters, such as costs and length of the procedure were reasonably well appreciated. The complexity of the procedure, however, was overestimated. Pacemaker function was poorly understood. All practitioner groups were less likely to refer for pacing compared with the experts, but were more likely to refer in the presence of recurrent symptoms, particularly if the patient was elderly. CONCLUSION: A conservative approach to referral for permanent pacing exists in the Waikato region and this is unrelated to access to diagnostic facilities or referral difficulties.

Identification of lead sources in residential environments: Sydney Australia.

Interior and exterior dust, soil and paint were analysed at five brick urban Sydney homes over 15 months to evaluate temporal variations and discriminate sources of lead (Pb) exposure. Exterior dust gauge Pb loading rates (µg/m(2)/28 days), interior vacuum dust Pb concentrations (mg/kg) and interior petri-dish Pb loading rates (µg/m(2)/28 days), were correlated positively with soil Pb concentrations. Exterior dust gauge Pb loading rates and interior vacuum dust Pb concentrations peaked in the summer. Lead isotope and Pb speciation (XAS) were analysed in soil and vacuum dust samples from three of the five houses that had elevated Pb concentrations. Results show that the source of interior dust lead was primarily from soil in two of the three houses and from soil and Pb paint in the third home. IEUBK child blood Pb modelling predicts that children's blood Pb levels could exceed 5 µg/dL in two of the five houses.

Intra- and Interobserver Reliability of the Cobb Angle-Vertebral Rotation Angle-Spinous Process Angle for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: A reliability analysis of Cobb angle, vertebral rotation (VR), and spinous process angle (SPA) measurements in adolescent idiopathic scoliosis. OBJECTIVE: To determine the intra- and interobserver reliability of semi-automated digital radiograph measurements. SUMMARY OF BACKGROUND DATA: Cobb angle measurements on posteroanterior radiographs are commonly used to determine the severity of scoliosis. Vertebral rotation helps assess scoliosis 3-dimensionally and has a role in predicting curve progression. Recent studies have shown that the spinous process angle is a useful parameter in assessing scoliosis when using ultrasound imaging. Because the reliability of SPA measurements on radiographs has yet to be determined, it is important to compare the reliability of these 3 parameters (Cobb angle, VR, and SPA) using a computer assisted semi-automated method. METHODS: Sixty posteroanterior radiographs of patients with adolescent idiopathic scoliosis were obtained and measured twice by 3 observers who were blinded to their previous measurements, using an in-house developed program. Measurements were obtained using a semi-automated method to minimize variability resulting from observer reliability. The intra- and interobserver reliabilities were analyzed using intra-class correlation coefficients (ICCs) as well as Bland-Altman's bias and limits of agreement. RESULTS: Over 350 (intra) and 90 (inter) sets of curves with an average Cobb angle of 26° ± 9° (range, 10° to 44°) were compared for each parameter. Intra-observer reliabilities for each parameter were excellent (ICC[2,1], .82; 1.00), with mean absolute differences under 3° between most measurements. Interobserver reliability (ICC[2,1], .72; .95) was mostly good to excellent, with mean absolute differences ranging from 2.0° to 5.6°. CONCLUSIONS: Both the intra- and interobserver assessment of the Cobb, VR, and SPA from the semi-automated measurements had clinically acceptable reliability ranges and may be considered for clinical implementation. Additional studies will be conducted to determine the accuracy and sensitivity to change of these scoliosis severity measurements.

Delay to angiography and outcomes following presentation with high-risk, non-ST-elevation acute coronary syndromes: results from the Global Registry of Acute Coronary Events.

OBJECTIVE: To test if delay-to-angiography (>72 hours from admission) in patients presenting with high-risk non-ST-elevation acute coronary syndromes (NSTE-ACS) is associated with adverse outcomes. DESIGN: GRACE (Global Registry of Acute Coronary Events) is a multinational registry of patients admitted with NSTE-ACS. SETTING: 14 countries with varying healthcare systems. PATIENTS: 23 396 high-risk NSTE-ACS patients with complete initial data collection entered into GRACE between 1999 and 2006 were analysed. INTERVENTIONS: Data were analysed according to delay-to-angiography and subsequent in-hospital or post-discharge adverse outcomes. MAIN OUTCOME MEASURES: Outcomes recorded included death, myocardial infarction, recurrent ischaemia, stroke, new heart failure and composite major adverse cardiovascular event (MACE) comprising death, cerebrovascular accident and myocardial infarction. Revascularisation procedures were recorded. RESULTS: 10 089 (43.1%) had no in-hospital angiography. Median delay-to-angiography was 46 hours; 3680 (34%) patients waited >72 hours. 9.3% waited >7 days before angiography. Patients waiting longest were more often older, diabetic, women and had a history of heart failure, previous myocardial infarction or hypertension. Recurrent in-hospital ischaemia (33% vs 22%), reinfarction (8.4% vs 5.0%) and heart failure (14% vs 9.1%) were more common with delayed angiography. Delayed angiography was associated with better outcomes than no angiography (MACE 18.9% vs 22.2%, p = 0.015). MACE rates within six months of admission were higher with longer delay-to-angiography and highest of all with no angiography. CONCLUSIONS: High-risk NSTE-ACS is suboptimally managed with 43% not undergoing angiography. One-third of those undergoing angiography are delayed >72 hours. Longer delays were more likely with higher risk, sicker patients. These delays were associated with adverse outcomes at six months. Very long delay was associated with lower MACE, but not mortality, compared to conservative management.

Sex-related differences in the presentation, treatment and outcomes among patients with acute coronary syndromes: the Global Registry of Acute Coronary Events.

OBJECTIVE: To assess whether sex differences exist in the angiographic severity, management and outcomes of acute coronary syndromes (ACS). METHODS: The study comprised 7638 women and 19 117 men with ACS who underwent coronary angiography and were included in GRACE (Global Registry of Acute Coronary Events) from 1999-2006. Normal vessels/mild disease was defined as <50% stenosis in all epicardial vessels; advanced disease was defined as >or=one vessel with >or=50% stenosis. RESULTS: Women were older than men and had higher rates of cardiovascular risk factors. Men and women presented equally with chest pain; however, jaw pain and nausea were more frequent among women. Women were more likely to have normal/mild disease (12% vs 6%, p<0.001) and less likely to have left-main and three-vessel disease (27% vs 32%, p<0.001) or undergo percutaneous coronary intervention (65% vs 68%, p<0.001). Women and men with normal and mild disease were treated less aggressively than those with advanced disease. Women with advanced disease had a higher risk of death (4% vs 3%, p<0.01). After adjustment for age and extent of disease, women were more likely to have adverse outcomes (death, myocardial infarction, stroke and rehospitalisation) at six months compared to men (odds ratio 1.24, 95% confidence interval 1.14 to 1.34); however, sex differences in mortality were no longer statistically significant. CONCLUSIONS: Women with ACS were more likely to have cardiovascular disease risk factors and atypical symptoms such as nausea compared with men, but were more likely to have normal/mild angiographic coronary artery disease. Further study regarding sex differences related to disease severity is warranted.

Implications of hyperglycaemia and ethnicity in patients with acute coronary syndromes in New Zealand.

BACKGROUND: Admission blood glucose (ABG) is an independent predictor of death in patients with acute ST elevation myocardial infarction (STEMI). In New Zealand, mortality following myocardial infarction is disproportionally higher in Maori. Little information, however, exists concerning the predictive value of ABG in non-ST elevation acute coronary syndromes (NSTEACS) events or indeed if similar ethnic differences exist in outcome in this patient population. AIM: To assess the predictive value of ABG and ethnicity in individuals admitted with acute coronary syndromes (ACS) on mortality. METHODS: A retrospective analysis of hospital discharge diagnosis of all ACS between 1 January 1999 and 31 December 2002 at Waikato hospital, Hamilton, New Zealand. The primary outcome was all-cause mortality. RESULTS: There were 4408 episodes of ACS with 1091 (25%) due to STEMI. There were 806 (18%) deaths. The presence of diabetes mellitus (DM) or an elevated ABG, in the absence of a history of DM, was associated with poor patient outcome. Early mortality is seen in individuals presenting with STEMI. People in the highest glucose category were older, more likely to be Maori, had a higher percentage of people with diabetes and remained in hospital longer, regardless of ACS type, than those in the lowest glucose category. Diabetes was more common in Maori (33%) than in Europeans (17.5%); p < 0.001. Significant risk factors for mortality were age, gender, diabetes, ethnicity, glucose and STEMI. For each mmol/l increase in glucose there is a 4.3% increase risk of dying. Adjusting for age and gender, Maori have a much higher mortality than Europeans (RR 2.12; p < 0.00001) regardless of ACS type (STEMI or NSTEACS). CONCLUSIONS: Our study confirms the higher mortality following ACS, of Maori compared to New Zealanders of European origin. A raised ABG is a marker of this increased risk in all patients with ACS.