Positive Angiography Research Articles

Predictors of Positive Angiography in Pelvic Fractures: A Prospective Study

Predictors of Positive Angiography in Pelvic Fractures: A Prospective Study

Predictors of Positive Angiography in Pelvic Fractures: A Prospective Study

Severe pelvic fractures continue to be a major problem for trauma surgeons. Early identification of patients who would benefit from therapeutic angiographic embolization (AE) of pelvic bleeding would be beneficial. We hope to identify simple risk factors that would pinpoint patients who would benefit from therapeutic AE. This is a prospective observational study at an academic Level I trauma center. All blunt trauma patients with a pelvic fracture admitted from December 2003 to February 2007 were included. AE was performed for hemodynamic instability (systolic blood pressure < 100 mmHg), fracture pattern (sacroiliac joint [SIJ] disruption, butterfly, open book), or CT demonstrating a large pelvic hematoma. AE was considered therapeutic if contrast extravasation was noted and addressed with embolization. Main outcomes measures were positive angiography and mortality. Stepwise logistic regression was performed to identify predictors of therapeutic AE. A predictive model was built based on these independent risk factors to estimate the probability of a therapeutic AE. One hundred thirty-seven (23%) of 603 patients with pelvic fractures had angiography. Therapeutic AE was performed in 85 patients (62%). Indications for angiography included hemodynamic instability (58%), fracture pattern (26%), and CT findings (9%). Nineteen patients (22%) with therapeutic AE had no hypotension or tachycardia. Independent predictors for therapeutic AE were SIJ disruption (odds ratio [OR]: 4.5; 95% CI, 1.6 to 12.6; p = 0.005), female gender (OR: 3.9; 95% CI, 1.5 to 10.0; p = 0.005), and duration (in minutes) of systolic blood pressure < 100 mmHg (OR: 1.4; 95% CI, 1.1 to 1.9; p = 0.007). Presence of SIJ disruption, female gender, and duration of hypotension can reliably predict patients who would benefit from AE. This predictive model can help early identification of patients who would benefit from pelvic angiography.

Pulmonary Embolism Outcome: A Prospective Evaluation of CT Pulmonary Angiographic Clot Burden Score and ECG Score

The purpose of this study was to establish whether a correlation exists between the CT pulmonary angiographic clot burden score, the ECG score at diagnosis, and the 12-month mortality rate among patients diagnosed with pulmonary embolism. A total of 523 consecutive patients who underwent CT pulmonary angiography for a suspected moderate to high pretest probability of pulmonary embolism were recruited from March 2003 to October 2004. There were 105 patients with positive CT pulmonary angiography examinations. Two consultant respiratory physicians and two consultant radiologists independently and prospectively calculated an ECG score and a quantified pulmonary artery clot burden, respectively. Twelve-month follow-up was completed in all patients. The mean ECG score was 2.36 (SD, 2.84) and the mean clot burden score percentage was 23.74% (16.8%). Poor correlation (r = 0.09) was seen between the average ECG score and the average clot burden score percentage (p = 0.39) at diagnosis. Thirteen patients had died at the 12-month follow-up. The mean ECG score for those patients who were alive was 2.4 (2.91) and for those who had died was 2.03 (2.34) at 12 months (p = 0.65). The mean clot burden score percentage for those patients who were alive was 24% (17%) and for those who had died was 22.1% (15.7%) at 12 months (p < 0.73). No statistically significant association was seen between ECG score and CT pulmonary angiographic clot burden at diagnosis and the 12-month all-cause mortality rate of patients diagnosed with pulmonary embolism.

The clinical application studies of CT spinal angiography with 64-detector row spiral CT in diagnosing spinal vascular malformations

Background and purpose To explore the value of CT spinal angiography with 64-detector row spiral CT in diagnosing spinal vascular malformations. Methods Seventeen patients with initial MR and clinical findings suggestive of spinal vascular diseases underwent CT spinal angiography. Among these, 14 patients took DSA examination within 1 week after CT scan, 7 patients underwent surgical treatment, and 6 patients underwent vascular intervention embolotheraphy. CT protocol: TOSHIBA Aquilion 64 Slice CT scanner, 0.5 mm thickness, 0.5 s/r, 120 kV and 350 mA, positioned at the aortic arch level, and applied with “sure start” technique with CT threshold of 180 Hu. Contrast agent Iohexol (370 mg I/ml) was injected at 6 ml/s velocity with total volume of 80 ml. The post-processing procedures included MPR, CPR, MIP, VR, etc. Among the 17 patients, four patients underwent fast dynamic contrast-enhanced 3D MR angiography imaging. CT spinal angiography and three-dimensional contrast-enhanced MR angiography (3D CE-MRA) images were compared and evaluated with DSA and operation results based on disease type, lesion range, feeding arteries, fistulas, draining veins of vascular malformation by three experienced neuroradiologists independently, using double blind method. The data were analyzed using SPSS analytic software with χ 2-test. We compared the results with DSA and operation results. Results The statistical analysis of the diagnostic results by the three experienced neuroradiologists had no statistical difference ( P > 0.05). All of the 17 patients showed clearly the abnormality of spinal cord vessels and the range of lesions by CT spinal angiography. Among them, one patient was diagnosed as arteriovenous fistulas (AVF) by MRI and CT spinal angiography, which was verified by surgical operation. DSA of the same patient, however, did not visualize the lesion. One case was diagnosed as AVM complicated with AVF by DSA, but CT spinal angiography could only show AVM not AVF. The type differentiations of all the other 16 patients were consistent with DSA results. For 13 cases with positive CT spinal angiography results, DSA displayed 20 feeding vessels, among which 16 vessels were displayed correctly by CT spinal angiography, four could not be visualized, and two turned out to be false-positive. Fistulas were not displayed in six cases by CT spinal angiography. Draining veins were displayed clearly in all cases, which agreed with DSA results. Four cases who took CE-MRA obtained the same type diagnosis as that from CT spinal angiography. Feeding arteries were not displayed in CE-MRA of one case, but could be clearly visualized in other three cases, and the results agreed with CTA and DSA results. Fistulas could be seen in two cases. Draining veins and the disease range could be displayed distinctly by 3D CE-MRA. Conclusion CT spinal angiography is quite valuable for diagnosing vascular malformation of spinal cord. It can be a screening exam before DSA, and has a guiding effect on DSA, reducing the amount of time required for DSA.

Thunderclap Headache With Normal CT and Lumbar Puncture

Thunderclap Headache With Normal CT and Lumbar Puncture

Computerised Tomography for the Detection of Pulmonary Emboli in Intensive Care Patients—a Retrospective Cohort Study

Pulmonary emboli are frequently considered as a cause for respiratory deterioration in intensive care unit (ICU) patients, however empirical observation suggests that computerised tomographic (CT) angiography is infrequently positive after the first 24 hours. This study aimed to determine the rate and risk factors for detection of pulmonary emboli by CT angiography in ICU patients. All patients undergoing CT angiography > 24 hours after ICU admission for respiratory deterioration from April 2000 until January 2004 were included. The positivity rate for pulmonary emboli was determined and risk factors analysed. Seven (6%) out of 113 CT angiograms were positive for pulmonary emboli. All were found in trauma patients. Comparing positive to negative scans, predefined risk factors including head injury (5/7 positive scans, 71% vs. 23/106 negative scans, 22%, P = 0.005), spine injury with neurological impairment (4/7, 57% vs. 9/106, 8%, P = 0.002) and lower limb injury (3/7, 43% vs. 12/106, 9%, P = 0.039) were significantly more frequent in patients with positive scans. Deep vein thrombosis prophylaxis was employed less frequently prior to a positive scan (in 3/7, 43% patients with positive scans vs. 91/106, 86% patients with negative scans P = 0.015). Only the predefined risk factors were independently associated with positive CT angiography on limited logistic regression (OR 24.7 per risk factor, 95% CI 2.38 to 255.1, P = 0.007). Pulmonary emboli were infrequently diagnosed using CT angiography in ICU patients admitted for more than 24 hours and found only in patients with recognised risk factors.

Cost-effectiveness of functional cardiac testing in the diagnosis and management of coronary artery disease: a randomised controlled trial. The CECaT trial

To assess the acceptability and feasibility of functional tests as a gateway to angiography for management of coronary artery disease (CAD), the ability of diagnostic strategies to identify patients who should undergo revascularisation, patient outcomes in each diagnostic strategy, and the most cost-effective diagnostic strategy for patients with suspected or known CAD. A rapid systematic review of economic evaluations of alternative diagnostic strategies for CAD was carried out. A pragmatic and generalisable randomised controlled trial was undertaken to assess the use of the functional cardiac tests: angiography (controls); single photon emission computed tomography (SPECT); magnetic resonance imaging (MRI); stress echocardiography. The setting was Papworth Hospital NHS Foundation Trust, a tertiary cardiothoracic referral centre. Patients with suspected or known CAD and an exercise test result that required non-urgent angiography. Patients were randomised to one of the four initial diagnostic tests. Eighteen months post-randomisation: exercise time (modified Bruce protocol); cost-effectiveness compared with angiography (diagnosis, treatment and follow-up costs). The aim was to demonstrate equivalence in exercise time between those randomised to functional tests and those randomised to angiography [defined as the confidence interval (CI) for mean difference from angiography within 1 minute]. The 898 patients were randomised to angiography (n = 222), SPECT (n = 224), MRI (n = 226) or stress echo (n = 226). Initial diagnostic tests were completed successfully with unequivocal results for 98% of angiography, 94% of SPECT (p = 0.05), 78% of MRI (p < 0.001) and 90% of stress echocardiography patients (p < 0.001). Some 22% of SPECT patients, 20% of MRI patients and 25% of stress echo patients were not subsequently referred for an angiogram. Positive functional tests were confirmed by positive angiography in 83% of SPECT patients, 89% of MRI patients and 84% of stress echo patients. Negative functional tests were followed by positive angiograms in 31% of SPECT patients, 52% of MRI patients and 48% of stress echo patients tested. The proportions that had coronary artery bypass graft surgery were 10% (angiography), 11% (MRI) and 13% (SPECT and stress echo) and percutaneous coronary intervention 25% (angiography), 18% (SPECT) and 23% (MRI and stress echo). At 18 months, comparing SPECT and stress echo with angiography, a clinically significant difference in total exercise time can be ruled out. The MRI group had significantly shorter mean total exercise time of 35 seconds and the upper limit of the CI was 1.14 minutes less than in the angiography group, so a difference of at least 1 minute cannot be ruled out. At 6 months post-treatment, SPECT and angiography had equivalent mean exercise time. Compared with angiography, the MRI and stress echo groups had significantly shorter mean total exercise time of 37 and 38 seconds, respectively, and the upper limit of both CIs was 1.16 minutes, so a difference of at least 1 minute cannot be ruled out. The differences were mainly attributable to revascularised patients. There were significantly more non-fatal adverse events in the stress echo group, mostly admissions for chest pain, but no significant difference in the number of patients reporting events. Mean (95% CI) total additional costs over 18 months, compared with angiography, were 415 pounds (-310 pounds to 1084 pounds) for SPECT, 426 pounds (-247 pounds to 1088 pounds) for MRI and 821 pounds (10 pounds to 1715 pounds) for stress echocardiography, with very little difference in quality-adjusted life-years (QALYs) amongst the groups (less than 0.04 QALYs over 18 months). Cost-effectiveness was mainly influenced by test costs, clinicians' willingness to trust negative functional tests and by a small number of patients who had a particularly difficult clinical course. Between 20 and 25% of patients can avoid invasive testing using functional testing as a gateway to angiography, without substantial effects on outcomes. The SPECT strategy was as useful as angiography in identifying patients who should undergo revascularisation and the additional cost was not significant, in fact it would be reduced further by restricting the rest test to patients who have a positive stress test. MRI had the largest number of test failures and, in this study, had the least practical use in screening patients with suspected CAD, although it had similar outcomes to stress echo and is still an evolving technology. Stress echo patients had a 10% test failure rate, significantly shorter total exercise time and time to angina at 6 months post-treatment, and a greater number of adverse events, leading to significantly higher costs. Given the level of skill required for stress echo, it may be best to reserve this test for those who have a contraindication to SPECT and are unable or unwilling to have MRI. Further research, using blinded reassessment of functional test results and angiograms, is required to formally assess diagnostic accuracy. Longer-term cost-effectiveness analysis, and further studies of MRI and new generation computed tomography are also required.

Abstract 3068: Intra-left Ventricular Contractile Dyssynchrony As An Independent Determinant Of Left Atrial Remodeling In Patients With Atrial Fibrillation Managed by Catheter-based Circumferential Pulmonary Venous Isolation

BACKGROUND. Enlarged left atrial volume (LAV), resulting from multifactorial pathogenesis, carries a poorer prognosis to patients with atrial fibrillation (AF) even under well rhythm control. We hypothesized that the preexistence of intra-left ventricular (LV) contractile dyssynchrony impaired diastolic filling, which contribute to atrial remodeling in AF patients. METHODS. We investigated 40 patients (34 men and 6 women, mean age 60 ± 10 years) with paroxysmal or persistent AF who were converted mainly by catheter ablation-based circumferential pulmonary venous isolation and then pharmacologically maintained in sinus rhythm. Exclusion criteria included significant (&gt;moderate) valvular heart disease, LV ejection fraction &lt;55 %, or ischemic heart disease confirmed by positive stress tests or coronary angiography. The LAV was measured by 2D echocardiography [π×D1×D2×D3/6 from parasternal long-axis view (D1) and apical four-chamber view (D2 &amp; D3)]. The peak myocardial systolic velocity (S M ) and the time to peak S M (T S ) of the 6-basal and 6-mid LV segments were measured by tissue Doppler imaging (TDI). RESULTS. With similar AF duration before conversion, patients with LAV &gt;40ml (n = 16) had similar baseline characteristics, cardiovascular medications, QRS width, and LV chamber sizes as those with LAV &lt;40ml (n = 24). However, TDI showed the mean S M was borderline lower (6.3 ± 1.2 vs. 7.1 ± 1.2 cm/s, p &lt; 0.05), and the maximal intersegmental difference in T S (77 ± 43 vs. 40 ± 22 ms, p &lt; 0.003) was greater in patients with larger LAV. The intersegmental difference in T S correlated positively with LAV (r = 0.41, p &lt; 0.009), and LV filling pressure estimated by early transmitral flow velocity/annular diastolic velocity was significantly higher (12.3 ± 7.8 vs. 8.7 ± 2.2, p &lt; 0.045) in patients with intersegmental difference in T S &gt;65 ms. After adjusting for age, gender, and the diastolic parameters, intersegmental difference in T S &gt;65ms emerged as an independent determinant of larger LAV in multivariate logistic analysis (OR=17; 95% CI=2–166, p &lt; 0.016). CONCLUSIONS. Intraventricular dyssynchrony, which accompanied with elevated LV filling pressure, contributed independently to LA remodeling in AF patients converted into sinus rhythm by catheter ablation.

Multi-slice CT (MSCT) angiography for assessment of traumatic lesions of lower limbs peripheral arteries

The aim of this study was to evaluate the feasibility and effectiveness of multi-slice computed tomography (MSCT) angiography for the assessment of traumatic lesions involving the arteries of the lower limbs. Forty-seven patients with suspected arterial post-traumatic lesions of lower limbs underwent MSCT angiography (4 x 2.5-mm collimation, 3-mm slice width). The standards of reference were: digital subtraction angiography (DSA; patients with inconclusive/doubtful or positive MSCT angiography indicating a need for intravascular treatment), surgical findings (patients with positive MSCT angiography indicating a need for surgery), or clinical/investigational follow-up (patients with negative MSCT angiography and no need for further diagnostic procedures or surgery). All CT exams were technically adequate. Sensitivity, specificity, and overall diagnostic accuracy of MSCT angiography were 96.3, 90, and 93.6%, respectively, relative to the reference of standard findings. In 44 out of 47 patients, MSCT angiography allowed a correct continuation of the diagnostic work-up. MSCT angiography is a reliable fast tool for diagnosing traumatic vascular lesions, providing results comparable to DSA.

A Prospective Evaluation of a Quantitative D-dimer Assay in the Evaluation of Acute Pulmonary Embolism

A prospective study was designed to determine if a screening quantitative serum D-dimer measurement of 1.0 microg/mL or less precludes pulmonary computed tomographic (CT) angiography in patients with possible acute pulmonary embolism (PE). Over a period of 16 months, every patient seen in the emergency department in whom there was clinical suspicion of PE sufficient to warrant pulmonary CT angiography was also requested to have a quantitative serum D-dimer level measurement taken. All pulmonary CT angiography procedures were performed on a four-slice scanner and every examination was overread by a radiologist who was blinded to the D-dimer assay results. Three-month medical record and telephone follow-up was carried out for all participants who had a serum D-dimer level of 1.0 microg/mL or less to verify no new diagnosis or death from PE. In this prospective study, 361 consecutive patients who received pulmonary CT angiography had a D-dimer level of 1.0 microg/mL or less. There were 310 patients who had negative pulmonary CT angiography results and 50 patients who had indeterminate CT angiography results. Only one patient had positive pulmonary CT angiography findings. Minimum 3-month follow-up information was available for 349 patients, none of whom reported subsequent PE, including those with indeterminate pulmonary CT angiography results. The use of a screening D-dimer measurement of 1.0 microg/mL or less precludes pulmonary CT angiography in patients with possible acute PE. The use of this quantitative D-dimer assay would decrease radiation exposure, contrast medium toxicity, cost, and time for patients seen in the emergency medicine department.

Relationship between Platelet Indexes and Coronary Angiographic Findings in Patients with Ischemic Heart Disease

To understand the mechanisms linking platelets to the risk of coronary artery disease, we investigated the relation between coronary angiographic morphology and platelet indexes – platelet count, mean platelet volume (MPV), platelet-large cell ratio (P-LCR) and platelet distribution width (PDW) – in patients with ischemic heart disease. Eighty-four patients with ischemic heart disease and 120 aged controls (AC) were enrolled in the study. The patients without any signs of acute myocardial infarction and acute coronary syndromes who underwent coronary angiography were divided into two groups, an ‘angiographically negative group’ (group 0) and an ‘angiographically positive group’ (group 1), with positive coronary obstruction depending on the diagnostic criteria in our hospital. Platelet indexes were measured in peripheral venous blood. The mean platelet counts were significantly lower in groups 1 and 0 than in AC (p = 0.0128 and p = 0.0041, respectively). MPV, P-LCR and the PDW were significantly higher in group 0 than in group 1 and AC (p = 0.0352 and 0.0433, p = 0.0059 and 0.0052, p = 0.00461 and 0.0146, respectively). The indexes of group 1 were almost the same compared with AC with respect to MPV, P-LCR and PDW. In conclusion, these findings suggest that the measurement of platelet indexes may reflect the underlying pathophysiological state and subsequent clinical events in the patients. In particular, lower P-LCR seems to identify patients with positive coronary angiography.

Should Spectrophotometry Be Used to Identify Xanthochromia in the Cerebrospinal Fluid of Alert Patients Suspected of Having Subarachnoid Hemorrhage?

The absence of xanthochromia in the cerebrospinal fluid (CSF) is often used to exclude subarachnoid hemorrhage (SAH). Authorities advocate spectrophotometry to measure xanthochromia, but most North American hospitals use visual inspection. We studied the diagnostic accuracy of spectrophotometry for SAH, and its potential impact on current practice. This was a prospective cohort study comparing the diagnostic accuracy of tests. The study was set in 3 university-affiliated tertiary care emergency departments. We enrolled consecutive neurologically intact adults with nontraumatic headache undergoing lumbar puncture (LP) to rule out SAH. CSF was centrifuged, frozen and analyzed later in batch. SAH was defined by (1) subarachnoid blood on CT, (2) >5x10(6) red blood cells/L in the final CSF tube and positive angiography, or (3) visible xanthochromia in CSF and positive angiography. All subjects lacking a normal CT and LP were telephoned at 30 days. We enrolled 220 patients (mean age 42+/-16 years; CT rate 87.7%; angiography rate 5.9%). Two SAHs were identified: 1 with red blood cells without xanthochromia in the CSF and 1 with visibly xanthochromic CSF. The specificity of xanthochromia was 97% (95% CI: 92% to 99%) for visual inspection, but as low as 29% (95% CI: 23% to 35%) for 2 of the spectrophotometric definitions. Introducing spectrophotometry could lead to angiography in as many as 11% to 71% of patients undergoing LP. Spectrophotometric definitions of xanthochromia have only moderate to low specificity for SAH. Using spectrophotometry could increase angiography rates, thereby identifying more incidental aneurysms, increasing patient anxiety and exposing patients to unnecessary surgical or investigational complications without benefit.

Clinical variables associated with positive angiographic localization of lower gastrointestinal bleeding

Localizing the source of severe lower gastrointestinal (GI) bleeding is often difficult but is important to plan the extent of colonic resection. The purpose of the present paper was to audit the Auckland Hospital experience of selective angiography, in localizing lower GI bleeding. Patients admitted to Auckland Hospital with rectal bleeding and who subsequently had angiography were evaluated by reviewing their clinical notes and radiological results during a 7-year period (1997-2003). Data collected included demographic details, haemodynamic parameters, change in haemoglobin level, requirement of blood transfusion within 24 h before the procedure, site of the bleeding and pathology. The notes of 88 patients (male, n = 51; median age 69 years, range 8-99 years) were available for review and analysis. The site of bleeding was localized in 38 (51%); 30 of them had bleeding in the right colon or small bowel and eight in the left colon. Positive localization correlated with: haemodynamic instability P < 0.0001; drop in haemoglobin level of > or =50 from previous admission (P = 0.02); transfusion requirement of > or =5 units of blood within 24 h (P < 0.0001). Logistic regression analysis showed transfusion requirement of > or =5 units to achieve haemodynamic stability to be the most powerful predictor of accurate localization (odds ratio, 40). Catheter angiography for acute lower GI bleeding will successfully localize a point of bleeding in approximately 50% of patients. The most useful clinical indicator for positive angiography was haemodynamic instability particularly in those who require transfusion of > or =5 units of blood to achieve haemodynamic stability.

Association of Subclinical Wall Changes of Carotid, Femoral, and Popliteal Arteries With Obstructive Coronary Artery Disease in Patients Undergoing Coronary Angiography

To examine the association of occult atherosclerosis of carotid, femoral, and popliteal arteries with the presence and severity of obstructive coronary artery disease (CAD) in patients without a history or presence of cerebrovascular or peripheral arterial disease using ultrasound examination of peripheral arteries. One hundred eighty-four such individuals underwent routine coronary angiography. Obstructive CAD was found in 103 cases, which comprised the patient group. The remaining 81 individuals comprised the control group. All were blindly examined by duplex ultrasonography in order to assess occult atherosclerosis, as indicated by the estimation of intima-media thickness of the carotid artery (IMTC), intima-media thickness of the femoral artery (IMTF), intima-media thickness of the popliteal artery (IMTP), and ultrasonic biopsy (UB) of the carotid and femoral arteries. For the individuals with positive coronary angiography findings, the severity of CAD was estimated by the number of the diseased vessels. IMTC, IMTF, IMTP, and UB showed significant correlation with the presence of obstructive CAD, but only IMTC and IMTF were independent predictive factors, with specificity of 74% and 60% and sensitivity of 76% and 70%, respectively. Additionally, our analysis yielded a regression model that, for a given value of IMTC and IMTF, may estimate the probability of CAD: p (CAD) = e((- 4.765 + 3.36 IMTC + 1.91 IMTF))/1 + e((- 4.765 + 13.36 IMTC + 1.91 IMTF)). Patients with one-vessel disease had significantly lower IMTC (p < 0.001) and UB (p = 0.011) and lower IMTF (p = 0.057) than those with three-vessel disease. The assessment of occult atherosclerosis by duplex ultrasonography in both the carotid and the femoral arteries is significantly associated with the presence and severity of CAD.

Dobutamine stress echocardiography predicts cardiac events or death in asymptomatic patients long-term after heart transplantation: 4-Year prospective evaluation

Background Cardiac allograft vasculopathy (CAV) remains the major cause of death after cardiac transplantation during long-term follow-up. Nevertheless, annual angiographic evaluation is difficult to perform routinely. We evaluated the value of clinical risk factors and non-invasive testing for cardiac allograft vasculopathy in predicting cardiac events or death in asymptomatic patients with normal ventricular function during long-term follow-up after heart transplantation. Methods We studied 39 patients, mean aged 48 ± 13 years, at 86 ± 31 months after heart transplantation. Patients underwent thallium scintigraphy, treadmill stress testing, dobutamine stress echocardiography, and angiography to detect CAV. We prospectively observed all patients an additional 4 years for acute myocardial infarction, congestive heart failure, or death. Results Angiography detected CAV in 15 patients (38%). Three patients had acute myocardial infarction and another 7 had congestive heart failure, representing 25% of cardiac events during the study period. Nine deaths (23%) occurred during the same observation time. Univariate analysis showed that increased body mass index, positive dobutamine stress echocardiography results, and positive angiography results were associated significantly with cardiac events or death during follow-up. In the absence of coronary angiography, stepwise logistic regression identified positive dobutamine echocardiography results as the unique independent predictor of cardiac events ( p = 0.001) or death ( p = 0.002). Conclusion Cardiac events and death after heart transplantation increased during long-term follow-up of this population. However, dobutamine stress echocardiography is well tolerated and, in the absence of routine angiographic evaluation, may be a strong predictor of these events.

Captopril test identifies severity of residual pressure gradient in recoartation

P-337 Key Words: Coarctation, Renin, Captopril

Coronary artery disease diagnosis based on exercise electrocardiogram indexes from repolarisation, depolarisation and heart rate variability.

Several indexes have been reported to improve the accuracy of exercise test electrocardiogram (ECG) analysis in the diagnosis of coronary artery disease (CAD), compared with the classical ST depression criterion. Some of them combine repolarisation measurements with heart rate (HR) information (such as the so-called ST/HR hysteresis); others are obtained from the depolarisation period (such as the Athens QRS score); finally, there are heart rate variability (HRV) indexes that account for the nervous system activity. The aim of this study was to identify the best exercise ECG indexes for CAD diagnosis. First, a method to automatically estimate repolarisation and depolarisation indexes in the presence of noise during a stress test was developed. The method is divided into three stages: first, a preprocessing step, where QRS detection, filtering and baseline beat rejection are applied to the raw ECG, prior to a weighted averaging; secondly, a post-processing step in which potentially noisy averaged beats are identified and discarded based on their noise variance; finally, the measurement step, in which ECG indexes are computed from the averaged beats. Then, a multivariate discriminant analysis was applied to classify patients referred for the exercise test into two groups: ischaemic (positive coronary angiography) and low-risk (Framingham risk index < 5%). HR-corrected repolarisation indexes improved the sensitivity (SE) and specificity (SP) of the classical exercise test (SE = 90%, SP = 79% against SE = 65%, SP = 66%). Depolarisation indexes also achieved an improvement over ST depression measurements (SE = 78%, SP = 81%). HRV indexes obtained the best classification results in our study population (SE = 94%, SP = 92%) by means of the very high-frequency power (VHF) (0.4-1 Hz) at stress peak.

Helicobacter pylori relation to acute myocardial infarction in an Iranian sample

Known risk factors for coronary heart diseases do not explain all of clinical and epidemiological features of the disease and additional environmental factors probably contribute to clinical atherothrombotic events. This study examined the association of Helicobacter pylori ( H. pylori ) infection with acute and chronic coronary syndromes assessed by coronary angiography as well as the influence of H. pylori on fibrinogen level. Paired sera from 52 patients with acute myocardial infarction (AMI) according to WHO criteria, 51 patients with positive coronary angiography and 55 patients with negative coronary angiography reports were investigated for antibodies to H. pylori and fibrinogen levels. H. pylori antibodies were determined by ELISA method. Plasma fibrinogen was measured by the Clauss assay. Coronary angiograms were reviewed by two cardiologists independently (weighted κ=0.64) and significant lesion was defined as ≥50% stenosis of at least one coronary vessel. There was significant relationship between H. pylori infection and acute myocardial infarction (Odds ratio=13.2, 95% CI=5.1–34.3, P =0.00), however, no significant difference between patients with positive or negative coronary angiography (Odds ratio=2.0, 95% CI=0.76–5.35, P =0.24) was seen. The crude prevalence of H. Pylori was not related significantly to the childhood socioeconomic class ( P >0.05) while showing significant inverse relationship with current socioeconomic class ( P <0.05). Fibrinogen levels were significantly higher among H. pylori positive than H. pylori negative patients (331.7±78.2 vs 304.6±66.4 mg/dl) ( P =0.04). While the Odds ratios for positivity of H. pylori antibodies in relation to smoking status, current socioeconomic classes were significant ( P <0.05), sex and childhood socioeconomic classes showed no significant association with H. pylori infection ( P >0.05). These results may support the hypothesis that H. pylori may influence acute myocardial infarction through enhancing thrombosis possibly mediated by raised fibrinogen level.

Evidence of parasympathetic impairment in some patients with cardiac syndrome X.

Cardiac syndrome X (SX) is a clinical condition characterised by angina, positive exercise stress test and negative coronary angiography; it has often been attributed to sympathetic hyperactivity. Here we tested the hypothesis that a parasympathetic, rather than a sympathetic, dysfunction could be the cause of the autonomic imbalance observed in SX. In 20 subjects with diagnosed SX and in 12 age-matched controls, we studied autonomic function by performing spectral analysis of RR interval and finger arterial pressure (SAP), in supine position and during head-up tilting. We also carried out a set of tests of parasympathetic function. The group of SX patients did not differ significantly from control subjects in any of the variables tested. In a subgroup of 13 SX, however, tilting increased the low-frequency power of SAP, but did not induce the expected increase in low-frequency and decrease in high-frequency power of RR. These patients, in supine position, had significantly lower sinus arrhythmia and a higher ratio of low to high frequency of RR, in comparison with control subjects. We interpreted these differences as signs of reduced parasympathetic, but essentially normal sympathetic, activity. The parasympathetic tests confirmed vagal impairment in the same SX subjects. On the other hand, all the tests indicated normal parasympathetic functions in the control subjects and in those SX patients who displayed the expected spectral changes in tilting. In about two thirds of the patients with SX, the pathophysiological mechanism causing the symptoms could be related to the reduced parasympathetic tone, rather than to an augmented sympathetic activity.

Prevention of Venous Thromboembolic Disease Following Primary Total Knee Arthroplasty

Patients treated with total knee arthroplasty are at high risk for the development of venous thromboembolism postoperatively. This study compared the efficacy and safety of two common thromboprophylactic agents, enoxaparin (a low-molecular-weight heparin) and warfarin. Three hundred and forty-nine patients were included in a prospective, randomized, multicenter, open-label, parallel-group clinical trial. Treatment with enoxaparin (30 mg, administered subcutaneously twice daily) or warfarin (adjusted to an international normalized ratio of 2 to 3) was initiated during the immediate postoperative period, within eight hours after the surgery, and was continued for four to fourteen days. Venous thromboembolism was defined as deep-vein thrombosis documented by contrast venography, symptomatic deep-vein thrombosis documented by lower-extremity ultrasonography, or symptomatic pulmonary embolism confirmed by a positive lung scan or pulmonary angiography. In the all-treated-patients group, eighty (45%) of the 176 warfarin-treated patients had venous thromboembolism: fifty-nine (34%) had distal deep-vein thrombosis; twenty (11%), proximal deep-vein thrombosis; and one (0.6%), pulmonary embolism. Venous thromboembolism developed in significantly fewer (p = 0.0001) enoxaparin-treated patients (forty-four of 173; 25%): forty-one (24%) had distal deep-vein thrombosis, three (2%) had proximal deep-vein thrombosis, and none had pulmonary embolism. The enoxaparin-treated patients also had a significantly lower prevalence of proximal deep-vein thrombosis (p = 0.002). The estimated odds for the development of venous thromboembolism were 2.52 times greater (95% confidence interval, 2.00 to 3.19) with warfarin than they were with enoxaparin. Major hemorrhage occurred in four warfarin-treated patients and nine enoxaparin-treated patients; with the numbers available, this difference was not significant (p = 0.17). Clinically important operative-site hemorrhage occurred in six (3%) of the warfarin-treated patients and twelve (7%) of the enoxaparin-treated patients (p = 0.15). A fixed 30-mg subcutaneous dose of enoxaparin, administered twice daily, with the first dose administered within eight hours after the completion of surgery, was significantly more effective than adjusted-dose warfarin in reducing the occurrence of asymptomatic venous thromboembolism, including proximal deep-vein thrombosis, in patients undergoing total knee arthroplasty. With the numbers available, there was no significant difference between groups with regard to the occurrence of major hemorrhagic complications; however, the rate of overall hemorrhagic complications was higher in the enoxaparin group.