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BACKGROUND: Studies have demonstrated considerable accuracy of multi-slice CT coronary angiography (MSCT-CA) in comparison to invasive coronary angiography (I-CA) for evaluating coronary artery disease (CAD). The extent to which published MSCT-CA accuracy parameters are transferable to routine practice beyond high-volume tertiary centres is unknown. AIM: To determine the accuracy of MSCT-CA for the detection of CAD in a Scottish district general hospital. DESIGN: Prospective study of diagnostic accuracy. METHOD: One hundred patients with suspected CAD recruited from two Glasgow hospitals underwent both MSCT-CA (Philips Brilliance 40 × 0.625 collimation, 50-200 ms temporal resolution) and I-CA. Studies were reported by independent, blinded radiologists and cardiologists and compared using the AHA 15-segment model. RESULTS: Of 100 patients [55 male, 45 female, mean (SD) age 58.0 (10.7) years], 59 and 41% had low-intermediate and high pre-test probabilities of significant CAD, respectively. Mean (SD) heart rate during MSCT-CA was 68.8 (9.0) bpm. Fifty-seven per cent of patients had coronary artery calcification and 35% were obese. Patient prevalence of CAD was 38%. Per-patient sensitivity, specificity, positive and negative (NPV) predictive values for MSCT-CA were 92.1, 47.5, 52.2 and 90.6%, respectively. NPV was reduced to 75.0% in the high pre-test probability group. Specificity was compromised in patients with sub-optimally controlled heart rates, calcified arteries and elevated BMI. CONCLUSION: Forty-Slice MSCT-CA has a high NPV for ruling out significant CAD when performed in a district hospital setting in patients with low-intermediate pre-test probability and minimal arterial calcification. Specificity is compromised by clinically appropriate strategies for dealing with unevaluable studies. Effective heart rate control during MSCT-CA is imperative. National guidelines should be utilized to govern patient selection and direct MSCT-CA reporter training to ensure quality control.

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A 38 year-old man with ulcerative colitis recently treated with balsalazide was admitted with chest pain. Investigations demonstrated myocardial necrosis, ECG changes, echocardiographic wall motion abnormalities but normal epicardial coronary arteries and no LV scar on cardiac MRI. Myocarditis was diagnosed and balsalazide therapy was withdrawn, resulting in a full recovery and resolution of abnormalities.

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AIM: To determine whether mortality following percutaneous coronary intervention vs. coronary bypass grafting varies according to whether or not patients have diabetes. METHODS: We used the Scottish Coronary Revascularization Register to identify all patients undergoing revascularization in Scottish NHS hospitals since 1997. We excluded single-vessel disease, left main stem stenosis, and bypass grafting performed at the same time as other operations. We used death certificate data from the Registrar General to identify all subsequent deaths. RESULTS: Of the 6320 eligible procedures, 5042 (80%) were bypass grafts and 1278 (20%) angioplasties. Overall 831 (13%) patients had diabetes with no significant difference by procedure (13% vs. 12%). A total of 382 deaths occurred over a mean follow-up of 2.3 years. Diabetic patients had a poorer prognosis following both surgery (adjusted hazards ratio (HR) 1.43, 95% confidence interval (CI) 1.08, 1.89) and percutaneous intervention (adjusted HR 2.58, 95% CI 1.43, 4.63). Among non-diabetic patients, no significant differences in mortality were detected between the two procedures. Among diabetic patients, no significant difference was detected in those with two-vessel disease. In those with impaired left ventricular function and triple-vessel disease, angioplasty was associated with a significantly higher risk of death (adjusted HR 3.58, 95% CI 1.40, 9.19). CONCLUSIONS: This is the first study to demonstrate statistically significant results that support the BARI trial findings. Our study demonstrated a significant difference for triple-vessel disease but not two-vessel disease. The former may be due to incomplete revascularization using percutaneous intervention. Our results require corroboration from randomized trials.

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Rapid access chest pain clinics are expanding across the country with marked resource implications despite a paucity of data regarding their efficacy. Early assessment of patients in this manner potentially delays review of patients referred via the traditional route. We conducted a prospective observational study of patients referred with chest pain to the Cardiology Outpatient Department over a four-week period in a District General Hospital to compare demographics and outcomes in patients referred to the rapid access with those referred to the general cardiology clinics. There were no significant differences in baseline demographics, exercise test result or clinic outcome. Both populations were low risk. Discussion is needed between primary and secondary care to achieve a consensus as to the purpose of a rapid access system and how best to utilise the service appropriately. Further studies are required to assess the efficacy and health economics of this system.

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Atrial fibrillation (AF) is a common arrhythmia associated with increased morbidity and mortality. Current practice aims to restore sinus rhythm (SR), although the question of whether rate or rhythm control is the optimal approach for these patients remains unanswered. The most established method of restoring SR in patients with AF of duration greater than 48 hours is external direct-current cardioversion (DCC). This is a descriptive paper summarising how we utilised the hospital's day surgery unit for the provision of DCC for patients with AF in order to provide a more efficient service and allow an increased number of procedures to be conducted. We describe the reasons for setting up the service and the methods involved. We also summarise the advantages associated with this new system.

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OBJECTIVE: To determine current outcomes of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG). DESIGN: The Scottish coronary revascularisation register provided prospectively collected data on case mix and in-hospital complications for all revascularisation procedures between April 1997 and March 1999 (4775 PTCA; 5115 CABG). Linkage to routine hospital discharge and death data provided follow up information on survival and repeat revascularisation. RESULTS: Stents were used in 51% of PTCA procedures. CABG patients were older, had more severe coronary disease, and had greater comorbidity. PTCA was more likely to be undertaken as an urgent or emergency procedure. Perioperative death and urgent surgery followed 0.3% and 0.6% of PTCA procedures, respectively. Case fatality rates were higher following CABG, with 6.7% dead within two years compared with 3.4% following PTCA. PTCA was more often followed by readmission for ischaemic heart disease, repeat angiography, or revascularisation: 22.8% of patients had repeat revascularisation within two years, compared with 1.8% following CABG. CONCLUSIONS: The severity of coronary heart disease was greater than in previously published registry studies and randomised trials. Despite this, overall survival figures were comparable and repeat revascularisation rates lower, particularly following PTCA. Perioperative death and urgent surgery following PTCA were also lower. These favourable outcomes may be attributable, in part, to increased use of bail out and elective stenting.

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We report the first case of permanent pacing via the coronary sinus in a patient with a Bjork-Shiley tricuspid valve replacement. This may be the route of choice in this group of patients.

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The objective was to prospectively validate a method of increasing the sensitivity, specificity and negative predictive value of a normal ECG in the exclusion of left ventricular systolic dysfunction by the addition of clinical history. We performed a prospective three year study of all referrals to our direct access ECHO service for assessment of LV function. The ECG was reported blind of the result of the ECHO, history of MI or not was noted, and result of the ECHO predicted. Over three years 416 patients were assessed for the presence or absence of left ventricular systolic dysfunction and consequent changes in clinical management. A total of 320(77%) of patients referred with suspected left ventricular dysfunction were found to have normal left ventricular function. Of the 250(60%) patients treated prior to referral for assessment, 183(73%) were treated inappropriately. The combination of a normal ECG and a negative history of myocardial infarction had a sensitivity of 98% and a negative predictive value of 99% in the assessment of LV function. This was an improvement over a normal ECG alone. Our study shows that diagnosis and treatment of heart failure in the community remains sub-optimal. The combination of a normal ECG and no previous history of myocardial infarction is shown to be a sensitive and accurate predictor of normal left ventricular function. If adopted by general practitioners this would be a valuable method of optimising the use of echocardiography in patients with suspected left ventricular dysfunction.

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BACKGROUND: Electrocardiography is the fundamental investigation for decision making regarding thrombolytic treatment in acute myocardial infarction (MI). Increasing the accuracy of ECG analysis by input from consultant staff may assist in management decisions in patients with suspected MI. AIMS: To evaluate a system whereby out of hours ECGs can be faxed to the consultant to aid in decision making regarding thrombolytic treatment. METHODS: 112 patients with suspected MI were assessed on admission by the senior house officer (SHO) who faxed to a cardiology consultant the ECG trace and a predesigned form with information on: clinical assessment of the patient; interpretation of the ECG; and views regarding administration of thrombolytic treatment including choice of agent. The consultant reviewed the information and communicated his views to the SHO. Subsequent diagnosis was recorded in all patients and the forms were analysed in regard to areas of agreement and disagreement between the SHO and the consultant. RESULTS: A diagnosis of MI was confirmed in 52 of the 112 patients (46.4%). The consultant agreed with the SHO's decision on thrombolysis in 98 patients (87.5%). The reason for disagreement in the remaining 14 patients (12.5%) was SHO misinterpretation of the ECG (10 patients) and clinical assessment (four patients). Eight patients were saved unnecessary thrombolytic treatment and four received it when they otherwise would not have. Additionally the choice of thrombolytic agent was changed in six patients from streptokinase to tissue plasminogen activator. CONCLUSION: The use of fax machine assists in decision making with regard to thrombolytic treatment and provides support to junior doctors in what can be a difficult, yet critical decision.

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BACKGROUND: Direct access to the coronary care unit (CCU) for general practitioner (GP) referred cases of suspected acute myocardial infarction (AMI) (fast track admission) substantially reduces the time to thrombolysis. Until now, this policy has been confined to GP referrals. OBJECTIVES: To determine the time taken to admission to CCU under the fast track policy (ambulance referrals and GP referrals) and the time taken to start administration of thrombolytics (ambulance referrals, GP referrals, and accident and emergency referrals). METHODS: Fast track admission policy was extended to include referrals from ambulance personnel who respond to emergency service calls. Ambulance personnel referred cases were also examined to see if they were referred appropriately to the CCU. RESULTS: 100 ambulance personnel referrals and 260 GP referrals to CCU with chest pain were studied. Forty accident and emergency referrals who had AMI requiring thrombolysis were also studied. In the ambulance referred group the time to admission from phone call was a median of 10 minutes (range 2 to 45), a saving of 30 minutes compared with GP referrals (median 40 minutes, range 2 to 217). The median diagnostic electrocardiogram (ECG) to thrombolysis time was longer in the accident and emergency referrals with AMI than either ambulance referrals or GP referrals admitted under the fast track policy. Diagnostic ECG to thrombolysis time: accident and emergency 50 minutes (range 15 to 385); ambulance referrals median 33 minutes (range 6 to 69); GP referrals median 29.5 minutes (range 5 to 110 minutes); (p = 0.056 accident and emergency compared with ambulance referrals, p < 0.002 accident and emergency compared with GP referrals). Of 100 ambulance referrals 52 patients exhibited symptoms suggestive of ischaemic heart disease (confirmed AMI, unstable angina, and angina) and a further 18 patients were required to stay in CCU for other cardiac problems. Thus a total of 70 (70%) were considered appropriate compared with 155 of 260 (55.8%) GP referred cases. CONCLUSIONS: Extending the fast track admission policy to ambulance personnel reduces delay to admission for patients with suspected MI without adversely affecting the appropriateness of admissions.

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OBJECTIVE: To evaluate the influence of pretreatment streptokinase resistance titre and the concentration of IgG antibodies to streptokinase on the efficacy of thrombolytic drugs containing streptokinase in restoring coronary patency in acute myocardial infarction. DESIGN: Comparative observational study. SETTING: City general hospital. PATIENTS: One hundred and twenty four previously unexposed patients presenting within six hours of onset of acute myocardial infarction. INTERVENTIONS: Streptokinase, 1.5 MIU as intravenous infusion over 60 minutes (60 patients), or anistreplase, 30 units as intravenous injection over five minutes (64 patients). MAIN OUTCOME MEASURES: Pretreatment streptokinase resistance titre and concentration of IgG antibodies to streptokinase were measured in 96 and 124 patients respectively and coronary patency assessed angiographically at 90 minutes and 24 hours. RESULTS: Pretreatment streptokinase resistance titre and concentrations of IgG antibodies to streptokinase were low and skewed towards higher values. Those patients with coronary occlusion at 24 hours had a significantly higher median streptokinase resistance titre (100 v 50 streptokinase IU ml-1, P = 0.02). There were trends towards a higher streptokinase resistance titre in those patients with coronary occlusion at 90 minutes (50 v 20 streptokinase IU ml-1, P = 0.06) and higher concentrations of IgG antibodies to streptokinase in those with coronary occlusion at both 90 minutes and 24 hours (1.53 v 0.925, P = 0.03; 1.65 v 1.04 micrograms streptokinase binding ml-1, P = 0.06). Coronary patency rates were similar in the two treatment groups. CONCLUSIONS: In the range measured in previously unexposed patients the streptokinase resistance titre has a small, but significant, negative influence on the efficacy of streptokinase and anistreplase. This effect should be considered if retreatment with streptokinase or anistreplase is proposed.

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A long duration of atrial fibrillation is usually considered as an adverse feature for successful cardioversion of atrial fibrillation and the maintenance of sinus rhythm. This often leads to the exclusion of such patients from being considered for this procedure. We report three patients in whom atrial fibrillation was present for a long duration (one for 2 years, two for 10 years), and successful cardioversion to sinus rhythm was achieved. Proper selection of patients with atrial fibrillation with an understanding of all features predicting a successful outcome will often allow a good result.

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Eighty patients (43 M, 37 F), aged 23-89 years who were referred for emergency echocardiography over a 12-month period were prospectively studied in order to determine the reasons for emergency echocardiography and the influence of its results on patient management. The most frequent emergency request was to clarify whether the basis for cardiomegaly in a haemodynamically unstable patient was pericardial effusion or left ventricular dilatation. Other reasons for requests were for assessment for source of systemic emboli, acute complications of myocardial infarction, endocarditis, valve dysfunction and cardiac trauma. As a consequence of the emergency echocardiography, management was immediately influenced in 19 patients. This study has provided information on the specific settings in which emergency echocardiography can be justified.

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The incidence, amplitude, mechanism and relationship to prior exposure to streptococcal antigen of blood pressure changes to streptokinase-containing thrombolytic agents were investigated in 125 patients treated with either 1.5 x 10(6) IU streptokinase over 60 min or 30 U anistreplase over 5 min, within 6 h of onset of acute myocardial infarction. Twenty-one of 52 patients with anterior and 34 of 73 with inferior myocardial infarction had a hypotensive response. There were no significant differences in the incidence, duration or amplitude of hypotension between the two treatment groups. The maximum mean fall in systolic blood pressure was 16.9 mmHg (95% confidence limits, CL 12.2 to 24.5 mmHg), and the maximum mean fall in diastolic blood pressure was 13.7 mmHg (CL 10.3 to 17.1 mmHg), starting 4 min after start of therapy and resolving within 34 min. Blood pressure changes were well tolerated. Hypotension was not related to pretreatment streptokinase resistance titre, or anti-SK IgG concentration, to changes in plasma fibrinogen, B-beta 15-42 peptide, D-dimer--as indices of thrombin activation and fibrin (-ogen) breakdown--to plasma viscosity. The blood pressure changes following treatment with streptokinase-containing thrombolytic agents in acute myocardial infarction are frequent but well tolerated. The mechanism of hypotension remains unclear, but is not related to prior exposure to streptococcal antigen.

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BACKGROUND: Sumatriptan (GR43175) is a selective 5-hydroxytryptamine (5HT1) receptor agonist effective in the acute treatment of migraine. Recent in vitro experiments suggest that it has vasoactive properties in vascular beds distinct from the cerebral circulation. The object of this study was to assess the vasoactive effects of the standard 6-mg subcutaneous dose of sumatriptan used in migraine on the systemic and pulmonary circulations and the coronary artery vasculature. METHODS AND RESULTS: Ten patients undergoing diagnostic coronary arteriography were studied with digital subtraction angiography and invasive hemodynamic monitoring. After subcutaneous injection of sumatriptan, there was no significant change in heart rate or ECG morphology. There was a significant rise in the systemic (20%, p < 0.05 by ANOVA) and pulmonary artery (40%, p < 0.05 by ANOVA) pressures. There was no change in cardiac output, but there was a significant increase in total systemic (27%, p < 0.05) and total pulmonary vascular resistance (40%, p < 0.05). Sumatriptan caused a significant reduction (p < 0.001 by ANOVA) in mean absolute coronary artery diameter, from 4.36 +/- 1.60 mm at baseline to 3.67 +/- 1.49 mm (16%) at 10 minutes and to 3.63 +/- 1.49 mm (17%) at 30 minutes after injection. There were no clinical sequelae. CONCLUSIONS: Sumatriptan, a 5HT1 receptor agonist administered by the subcutaneous route, causes a vasopressor response in the systemic and pulmonary arterial circulations and coronary artery vasoconstriction.

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1. Sumatriptan (GR43175) is a selective 5-HT1-receptor agonist effective in the acute treatment of migraine. Vasoactive properties in other vascular beds have been suggested by recent in vitro studies. 2. Its effects on coronary artery dimensions and central haemodynamics were assessed in 10 patients undergoing diagnostic coronary arteriography using digital subtraction angiography and invasive haemodynamic monitoring. 3. Following a 10 min i.v. infusion of sumatriptan to a total dose of 48 micrograms kg-1 there was a significant increase (P < 0.05) in systemic and pulmonary arterial pressures. There was a significant reduction in coronary artery diameter from 4.3 +/- 1.6 mm to 3.6 +/- 1.6 mm 12.9 +/- 6.9% (P < 0.001). There was no significant change in heart rate or ECG morphology. 4. Sumatriptan, a 5-HT1-receptor agonist, causes a vasopressor response in the systemic and pulmonary arterial circulations and coronary artery vasoconstriction; in this study there were no clinical sequelae.

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OBJECTIVE: To examine the induction of antistreptokinase antibodies after giving streptokinase or anistreplase to patients with acute myocardial infarction. DESIGN: Patients were randomly allocated to receive either 1.5 x 10(6) IU, streptokinase or 30U anistreplase in a double blind study. Blood samples were collected immediately before treatment and subsequently at intervals up to 30 months; plasma samples were assayed for streptokinase resistance titre (functional assay) and streptokinase binding by IgG (microradioimmunoassay). SETTING: Cardiology department in a general hospital. PATIENTS: 128 consecutive eligible patients. Samples were collected for up to one year according to a prospective design: a subsection of 47 patients was selected for intensive study over the first 14 days. After one year, all available patients (67) were sampled on one further occasion. RESULTS: Antibody responses to streptokinase and anistreplase were similar. Streptokinase resistance titres exceeded pretreatment concentrations five days after dosing, and values peaked at 14 days. By 12 months after dosing, 92% of resistance titres (n = 84) had returned to within the pretreatment range. Antistreptokinase IgG concentrations also exceeded baseline concentrations within five days and peaked at 14 days. Half of the individual values had returned to within the pretreatment range by 12 months (n = 84) and 89% by 30 months (n = 18). CONCLUSION: Although we cannot be sure of the clinical significance, because of the increased likelihood of resistance due to antistreptokinase antibody, streptokinase and anistreplase may not be effective if administered more than five days after an earlier dose of streptokinase or anistreplase, particularly between five days and 12 months, and increased antistreptokinase antibody may increase the risk of allergic-type reactions.

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OBJECTIVE: To examine the efficacy, safety, and the pharmacokinetic profile of a bolus dose administration regimen of alteplase in the treatment of acute myocardial infarction. DESIGN: An open pilot study. SETTING: District general hospital. PATIENTS: 33 suitable consecutive patients presenting within six hours of the onset of symptoms who satisfied the electrocardiographic criteria for acute myocardial infarction. INTERVENTIONS: Two intravenous boluses of 35 mg alteplase, 30 minutes apart. MAIN OUTCOME MEASURES: Angiographic coronary patency at 90 minutes and 24 hours. Plasma alteplase concentration-time profile and pharmacokinetic analysis. RESULTS: Coronary patency at 90 minutes: 26 of 30 arteries (87%, 95% confidence interval (CI) 74-99%). Coronary patency at 24 hours: 24 of 29 arteries (83%, CI 69-97%). Mean (SD) plasma tissue plasminogen activator (t-PA) concentration reached 4434.8 (2117.8) and 4233.3 (2217.5) ng/ml within 10 minutes of each bolus and fell to 425.8 (288.3) ng/ml between boluses. The estimated peak concentrations at two minutes after boluses were 12,389 (8580) ng/ml and 10,811 (6802) ng/ml. The derived pharmacokinetic variables were volume of distribution 3.11 (1.89) 1, clearance 21.3 (9.3) 1/h, half life 5.9 (1.7) minutes. CONCLUSIONS: This simple administration regimen achieved brief, high concentrations of plasma t-PA that were well tolerated. The regimen was associated with a high coronary patency rate at 90 minutes that was well maintained at 24 hours.

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