Potential impact of antiarrhythmic drugs versus implantable defibrillators on the management of ventricular arrhythmias: the Midlands trial of empirical amiodarone versus electrophysiologically guided intervention and cardioverter implant registry data

Background—Survival was prolonged in selected patients with sustained ventricular arrhythmias who received implantable cardioverter defibrillators (ICDs) in the antiarrhythmics versus implantable defibrillators (AVID) study. The Midlands trial of empirical amiodarone versus electrophysiologically guided intervention and cardioverter implant in ventricular arrhythmias (MAVERIC) registry is a population based trial.
Objective—To determine the number of patients who satisfy the AVID criteria because of the high cost of ICDs.
Design—Observational study, based on a continuing trial.
Setting—All coronary care units in the Midlands region in the United Kingdom (population 9.1 million).
Patients—Patients presenting to a coronary care unit with sustained ventricular arrhythmias not related to an acute myocardial infarction are entered onto the registry. Those who consent to the MAVERIC study are randomised to receive either empirical amiodarone or electrophysiologically guided treatment. Demographic data, details of clinical presentation, and echocardiographic findings are collected. These data have been used to calculate the number of patients who satisfy the AVID criteria and would benefit from ICD implantation. The financial implications have been calculated for the region and nationally.
Results—132 patients were entered onto the registry during the first five months of the MAVERIC study; 69 patients fulfilled the AVID criteria. Extrapolation of these data over a 12 month period suggests implantation of at least 166 new ICDs (compared with 23 implants in 1996). This would increase the UK ICD implant rate from five to at least 18 per million of the population, costing the National Health Service £24.1 million per annum.
Conclusion—Application of the AVID criteria in the UK will cause a great increase in the ICD implant rate, with serious financial implications.

Keywords: AVID study;  MAVERIC trial;  implantable cardioverter defibrillator;  economics;  arrhythmias     

Long term intravenous prostaglandin (epoprostenol or iloprost) for treatment of severe pulmonary hypertension

Objective—To investigate the relation between the severity of pulmonary hypertension and the outcome of medical treatment.
Methods—98 patients with primary pulmonary hypertension—nine (6%) with systemic disease and pulmonary hypertension and 39 (27%) with thromboembolic pulmonary hypertension—received medical treatment and were followed between 1982 and 1995. They were given long term intravenous prostaglandin treatment (either epoprostenol (n = 61) or iloprost (n = 13)) or conventional treatment with oral anticoagulants (n = 24) with or without calcium channel blockers. Event-free survival was measured to death or transplant surgery, or pulmonary thromboendarterectomy.
Results—Prognosis (hazard ratio) was affected by: New York Heart Association grade, 1.52 (95% confidence interval 1.11 to 2.09); mixed venous oxygen saturation (SvO₂%), 0.97 (0.95 to 0.98); cardiac index, 0.72 (0.49 to 1.06); mean right atrial pressure, 1.04 (1.01 to 1.07); and pulmonary vascular resistance, 1.02 (1.00 to 1.04). The median event-free survival time of patients with SvO₂ < 60% was 239 days (0 to 502) on conventional treatment (n = 22) and 585 days (300 to 870) on prostaglandin treatment (n = 42). No difference was seen in patients with SvO₂  60% between conventional treatment and prostaglandin treatment, survival being 1275 days (732 to 1818; (n = 48)) and 986 days (541 to 1431; n = 30)), respectively. Capacity for pulmonary vasodilatation did not predict outcome of treatment.
Conclusions—Continuous intravenous prostaglandins were more effective than anticoagulants, with or without calcium channel blockers, in prolonging survival in patients with right heart failure. In these patients a capacity to vasodilate did not predict outcome from medical treatment.

Keywords: prostacyclin;  iloprost;  pulmonary hypertension;  event-free survival     

Early and intermediate term clinical outcome after multiple coronary stenting

Objective—To examine the immediate and intermediate term clinical outcome of multiple coronary stenting.
Design—Consecutive patients were prospectively entered on a dedicated database. Follow up information was obtained from outpatient and telephone interviews with patients and family physicians.
Setting—A tertiary referral centre.
Patients—140 consecutive patients underwent multiple coronary stenting between April 1994 and November 1996. Most patients had unstable coronary syndromes.
Main outcome measures—Death, cerebrovascular accidents, myocardial infarction (MI), coronary artery bypass surgery (CABG), and repeat angioplasty (PTCA).
Results—The angiographic success rate was 100% and the clinical procedural success rate 93%. The mean (SD) follow up was 11.9 (7.2) months (range 2-32). The mean (SD) number of stents per patient was 2.4 (0.7). The mean (SD) number of lesions treated per patient was 1.4 (0.6). There were four in-hospital deaths (2.9%) and five patients (3.6%) had an MI before hospital discharge. All in-hospital deaths occurred in patients presenting with an acute MI and cardiogenic shock. Three patients (2.2%) had a late MI. One patient with stent thrombosis underwent emergency CABG. Three patients (2.2%) underwent late CABG. Eight patients (5.7%) had a repeat PTCA. Eighty three patients (61.5%) were asymptomatic at follow up and 121 (86.4%) were free from major clinical events.
Conclusion—In an era of increased operator experience, high pressure stent deployment, and reduced anticoagulation with antiplatelet treatment alone, multiple coronary stenting may be performed with a high procedural success rate and good intermediate term outcome.

Keywords: angioplasty;  stents;  clinical outcome;  interventional cardiology     

Outcomes of transposition of the great arteries in the era of atrial inflow correction

Objective—To examine long term morbidity and mortality following atrial inflow corrective procedures for transposition of the great arteries (TGA) and to investigate factors that influence morbidity and mortality.
Design—Retrospective cohort study from a single centre.
Setting—Cardiology and cardiothoracic surgical unit in a large tertiary referral centre.
Patients—All 130 patients who had TGA diagnosed between August 1972 and May 1988 and were considered suitable for atrial inflow correction; 109 of these underwent surgery (operative cohort: 84 Mustard operations and 25 Senning operations); 95 survived to hospital discharge (hospital surviving cohort).
Main outcome measures—Death and cardiac events.
Results—There were relatively good long term results from atrial inflow correction for TGA with 5, 10, and 15 year survivals of 77.3%, 75.9%, and 71.3%. However, there was an appreciable incidence of late cardiac death and events, with 5, 10, and 15 year cardiac event-free survivals of 74.5%, 67.1%, and 39.6%. Supraventricular tachycardia was the only significant risk factor for late cardiac death (relative risk 8.72, 95% confidence interval, 2.86 to 26.64). Senning patients had better event-free survival (p = 0.04).
Conclusions—Atrial inflow correction for TGA has a reasonably good 15 year survival (71.3%), but there is an appreciable incidence of late cardiac deaths and events (15 year event-free survival 39.6%). The Senning procedure is preferable to the Mustard procedure for cases unsuitable for arterial switching.

Keywords: transposition of the great arteries; congenital heart disease; Mustard operation; Senning operation     

Heartstart Scotland: the use of paramedic skills in out of hospital resuscitation

Objective—To assess the frequency with which paramedic skills were used in out of hospital cardiac arrest and the effect of tracheal intubation on outcome.
Design—Retrospective analysis of ambulance service reports and hospital records.
Setting—Scottish Ambulance Service and hospitals admitting acute patients throughout Scotland.
Results—A total of 8651 out of hospital resuscitation attempts were recorded and tracheal intubation was attempted in 3427 (39.6%) arrests. One hundred and thirty six patients (3.7%) were intubated and 476 (9.1%) of the patients who were not intubated survived to hospital discharge (p < 0.001). Among the patients who were defibrillated the proportion intubated was highest in the patients who received the greatest number of shocks (p < 0.01). Among subjects receiving similar numbers of shocks survival rates were lower for intubated patients (p < 0.01). Patients with unwitnessed arrests were most frequently intubated and survival rates were lowest in this group.
Conclusions—Patients who are intubated seem to have lower survival rates. This may however reflect the difficulty of the resuscitation attempt rather than the effects of intubation. The use of basic life support skills rapidly after cardiac arrest is associated with the best survival rates.

Keywords: paramedics;  resuscitation;  myocardial infarction;  tracheal intubation;  prehospital care     

Fibrinolytic potential is significantly increased by oestrogen treatment in postmenopausal women with mild dyslipidaemia

Objective—To study the effects of oestrogen replacement treatment on fibrinolytic potential in postmenopausal women.
Design—Randomised, double blind, placebo controlled trial of oral 17β-oestradiol.
Setting—Subjects were evaluated in the outpatient setting.
Patients—Nineteen postmenopausal women with mild dyslipidaemia, aged 44 to 69 years (mean (SD) 55.7 (6.7)).
Main outcome measures—Fibrinolytic activity (fibrin plate assay) and tissue plasminogen activator (t-PA) antigen were measured at baseline and after three, six, and nine weeks of each treatment.
Results—After nine weeks of 2 mg oestradiol treatment, there was a significant increase in fibrinolytic potential compared with placebo, as indicated by an increase in fibrinolytic activity (mean (SEM), 80 (9) v 54 (5) mm² of lysis in the fibrin plate, 2 mg v placebo, p = 0.002) and a decrease in t-PA antigen (5.8 (0.9) v 8.4 (1.2) ng/ml, 2 mg v placebo, p < 0.001). There was a similar trend with the 1 mg dose but the changes were less noticeable.
Conclusions—Hormone replacement treatment with 17β-oestradiol for nine weeks significantly increased fibrinolytic potential in postmenopausal women with mild dyslipidaemia. This suggests that the cardioprotective effect of oestrogen may be mediated, in part, by an increase in fibrinolytic potential.

Keywords: oestrogen;  fibrinolysis;  randomised controlled trial;  dyslipidaemia     

Cost effective management programme for heart failure reduces hospitalisation

Objective—To study the effects of a management programme on hospitalisation and health care costs one year after admission for heart failure.
Design—Prospective, randomised trial.
Setting—University hospital with a primary catchment area of 250 000 inhabitants.
Patients—190 patients (aged 65-84 years, 52.3% men) hospitalised because of heart failure.
Intervention—Two types of patient management were compared. The intervention group received education on heart failure and self management, with follow up at an easy access, nurse directed outpatient clinic for one year after discharge. The control group was managed according to routine clinical practice.
Main outcome measures—Time to readmission, days in hospital, and health care costs during one year.
Results—The one year survival rate was 71.8% (n = 79) in the control group and 70.0% (n = 56) in the intervention group (NS). The mean time to readmission was longer in the intervention group than in the control group (141 (87) v 106 (101); p < 0.05) and number of days in hospital tended to be fewer (4.2 (7.8) v 8.2 (14.3); p = 0.07). There was a trend towards a mean annual reduction in health care costs per patient of US$1300 (US$1 = SEK 7.76) in the intervention group compared with costs in the controls (US$3594 v 2294; p = 0.07).
Conclusions—A management programme for patients with heart failure discharged after hospitalisation reduces health care costs and the need for readmission.

Keywords: heart failure;  hospitalisation;  management;  health care costs;  nurse led clinics     

Shrinkage of human coronary arteries is an important determinant of de novo atherosclerotic luminal stenosis: an in vivo intravascular ultrasound study

Objective—To assess the occurrence of arterial remodelling types and its relation with the severity of luminal stenosis in atherosclerotic coronary arteries.
Patients and methods—Twenty one de novo coronary lesions of 20 patients, who were scheduled for percutaneous transluminal coronary angioplasty (PTCA), were investigated with intravascular ultrasound before PTCA. Local arterial remodelling at the lesion site was studied by measuring the cross sectional area circumscribed by the external elastic lamina (EEL) relative to the reference site: (EEL area lesion/reference EEL area) × 100%. Three groups were defined. Group A: relative EEL area of less than 95% (shrinkage), group B: relative EEL area between 95% and 105% (no remodelling), group C: relative increase in EEL area of more than 105% (compensatory enlargement).
Results—All three types of remodelling were observed at the lesion site: group A (shrinkage) n = 8, group B (no remodelling) n = 5, group C (compensatory enlargement) n = 8. The mean (SD) relative EEL area at the lesion site in group A and C was 83(9)% and 132(30)%, respectively. In group A, 33% of the luminal area stenosis at the lesion site was caused by shrinkage of the artery. In contrast, group C showed that 87% of the plaque area did not contribute to luminal area stenosis because of compensatory arterial enlargement.
Conclusions—These results show that both compensatory enlargement and paradoxical shrinkage occurs in the atherosclerotic coronary artery. Next to plaque accumulation, the type of atherosclerotic remodelling is an important determinant of luminal narrowing.

Keywords: coronary arteries; atherosclerosis; remodelling; intravascular ultrasound     

Predictors of event-free survival after percutaneous mitral commissurotomy

Objective—To assess the long term functional result after percutaneous mitral commissurotomy and identify the predictors of event-free survival following 10 years of experience.
Design—Analysis of clinical, echocardiographic, and haemodynamic variables at baseline and after the procedure by univariate and multivariate analyses (Cox model).
Setting—University hospital.
Patients—532 consecutive patients receiving percutaneous mitral commissurotomy in the same institution.
Results—The mean (SD) follow up was 3.8 (4.0) years. Survival at 3, 5, and 7.5 years was 94%, 91%, and 83%, respectively; event-free survival was 84%, 74%, and 52%. Mitral valve anatomy was identified as the strongest independent predictor of event-free survival. Age, cardiothoracic ratio, mean pulmonary artery pressure, and mean echocardiographic mitral gradient after commissurotomy were also found to be independent predictors of long term functional result. Event-free survival was 92%, 84%, and 70% at 3, 5, and 7.5 years in patients with favourable anatomy (echo score = 1), 86%, 73%, and 34% in patients with intermediate anatomy (echo score = 2), and 45%, 25%, and 16% in patients with unfavourable anatomy (echo score = 3). In patients aged 65 years, the event-free survival rate was 80%, 70%, and 45% at 3, 5, and 7.5 years v 52%, 38%, and 17% in patients aged > 65 years.
Conclusions—The anatomical form of the mitral valve and the patient's age were the most powerful predictors of event-free survival. Patients with intermediate or unfavourable anatomy and those aged > 65 years have low 5 and 7.5 year event-free survival rates. This must be taken into account when discussing the indications for percutaneous mitral commissurotomy; immediate mitral valve replacement is a reasonable alternative to balloon mitral commissurotomy in patients with higher risk of functional deterioration after the procedure.

Keywords: valvoplasty; mitral valve stenosis     

Combination treatment with trimetazidine and diltiazem in stable angina pectoris

Objective—To assess antianginal efficacy and possible adverse haemodynamic effects of combination treatment with trimetazidine and diltiazem in patients with stable angina.
Design—Double blind, randomised, placebo controlled trial of four weeks duration.
Setting—Outpatient department of two Indian hospitals.
Subjects—64 male patients with stable angina, uncontrolled on diltiazem alone.
Interventions—Diltiazem 180 mg and trimetazidine 60 mg, or diltiazem 180 mg and placebo daily.
Main outcome measure—Change in exercise time to 1 mm ST segment depression.
Results—33 patients (55%) had no exercise induced angina at 3 mm ST segment depression at inclusion in the study (silent ischaemia). Intention to treat analysis showed that of 32 patients in each treatment group, the number (%) of patients responding to trimetazidine compared to placebo was: for anginal attacks, 28 (87.5) v 15 (46.9), p < 0.001; for exercise time to 1 mm ST segment depression, 21 (65.6) v 9 (28.1), p < 0.003; for exercise time to angina, 12 (37.5) v 5 (15.6), p < 0.05; and for maximum work at peak exercise, 17 (53.1) v 8 (25), p < 0.02. Compared to placebo, there was net improvement with trimetazidine in mean anginal attacks of 4.8/week (95% confidence interval (CI) 7.5 to 2.1; p < 0.002); in mean exercise times at 1 mm ST segment depression of 94.2 seconds (95% CI 182.8 to 5.6; p < 0.05), and at onset of angina of 113.1 seconds (95% CI 181.6 to 44.6; p < 0.02); and in mean maximum work at peak exercise of 1.4 metabolic equivalents (95% CI 2.4 to 0.3; p < 0.05).
Conclusions—Patients with stable angina uncontrolled with diltiazem had a clinically important improvement after combination treatment with trimetazidine, without adverse haemodynamic events or increased side effects.

Keywords: trimetazidine;  diltiazem;  blood pressure;  stable angina;  treatment     

Ten year follow up of patients referred for coronary artery bypass grafting from a single district general hospital

Objective—To determine the status of patients 10 years after referral for coronary artery bypass graft (CABG) surgery.
Design—Retrospective analysis of case notes from all patients referred between 1 April 1981 and 31 March 1985. Full information gathered from hospital notes, GP records, and Registrar General for Scotland.
Setting—District General Hospital, West Lothian, Scotland.
Patients—102 patients referred for CABG during study period. Cardiac surgery was undertaken in Brompton Hospital, London, Royal Infirmary, Edinburgh, and Western Infirmary, Glasgow.
Results—At 10 years after operation 32 patients had died (27 cardiac, five non-cardiac causes). Full data were not available for five patients. Of the 65 remaining patients 24 had no angina, 13 had had a repeat procedure (CABG or angioplasty), and 28 had angina.
Conclusions—Long term benefits of CABG surgery is disappointing. Further steps are required to reduce progression of disease in this population.

Keywords: coronary artery bypass surgery;  repeat procedure;  survival;  audit     

Reduction in treatment delay by paramedic ECG diagnosis of myocardial infarction with direct CCU admission

Objectives—To establish the feasibility of training paramedics to diagnose acute myocardial infarction by ECG before hospital admission and whether direct paramedic coronary care admission, arranged by very high frequency (VHF) radio communication with the coronary care unit (CCU), would reduce delay of thrombolysis treatment.
Design—Prospective controlled study.
Setting—District general hospital CCU and a local district ambulance paramedic service.
Patients—124 patients with ECG evidence of myocardial infarction or ischaemia admitted directly to the CCU by the paramedic service were compared with 123 patients admitted by the emergency department and subsequently transferred to the CCU.
Main outcome measures—ECG diagnostic accuracy by paramedics, and interval durations for CCU admission and thrombolysis.
Results—ECG diagnostic accuracy by the paramedics was 87.5% in the training phase and 92% in admission. The total call to thrombolysis interval was reduced from 154 to 93 minutes and the "door to needle" interval was reduced from 97 to 37 minutes.
Conclusions—Trained paramedics can reliably diagnose myocardial infarction by ECG. The use of a direct admission procedure, by a VHF radio link to the CCU, substantially reduces the time interval for thrombolytic treatment after acute myocardial infarction.

Keywords: myocardial infarction;  electrocardiogram;  thrombolysis;  paramedic     

Bradykinin induced dilatation of human epicardial and resistance coronary arteries in vivo: effect of inhibition of nitric oxide synthesis

Objective—To clarify whether endothelium derived nitric oxide contributes to exogenous bradykinin induced dilatation of human epicardial and resistance coronary arteries in vivo.
Design—Quantitative coronary angiography and Doppler flow velocity measurements were used to determine the effects of the nitric oxide synthesis inhibitor, N^G-monomethyl-L-arginine (L-NMMA), on bradykinin induced dilatation of the epicardial and resistance coronary arteries.
Setting—Hiroshima University Hospital.
Patients—20 patients (16 men and four women, mean (SD) age 56 (9) years) with angiographically normal smooth epicardial coronary arteries.
Interventions—Serial infusions of bradykinin (0.5, 1.5, and 2.5 µg/min) were given into the left coronary ostium before and after L-NMMA infusion (60 µmol/min).
Main outcome measures—Epicardial coronary diameter, coronary blood flow, and coronary vascular resistance.
Results—Bradykinin-induced epicardial coronary vasodilatation after L-NMMA (dilatation by 2.5 µg/min, 3.8(1.4)% in the proximal and 5.9(1.8)% in the distal segments, mean (SEM)) was less (p < 0.001, respectively) than before L-NMMA (11.7(2.5)% and 15.1(2.0)%, respectively). In contrast, L-NMMA did not affect the bradykinin induced increase in coronary blood flow and decrease in coronary vascular resistance.
Conclusions—Endothelium derived nitric oxide contributes to bradykinin induced dilatation of epicardial coronary arteries, but may be less important in coronary resistance vasodilatation.

Keywords: bradykinin;  nitric oxide;  coronary artery;  coronary blood flow     

Transferring patients for primary angioplasty: a retrospective analysis of 104 selected high risk patients with acute myocardial infarction

Objective—To investigate the feasibility of primary coronary angioplasty as a treatment option in patients with acute myocardial infarction after initial diagnosis in a local community hospital.
Setting—Referral centre for interventional treatment of coronary artery disease.
Methods—During a five year period, 520 candidates for primary coronary angioplasty were treated in our institution, 104 after transfer from a community hospital. The transferred patients and the non-transferred patients (n = 416) were compared with regard to baseline clinical characteristics, time interval from symptom onset to treatment, and clinical outcome at six months.
Results—In this setting, the influence of transportation on total ischaemic time was limited, and there was no difference in clinical outcome between the transferred and the non-transferred patients. Clinical outcome was mainly dependent on the indication for transfer.
Conclusions—Safe and expedient transportation may facilitate the more widespread use of primary angioplasty in patients with acute myocardial infarction. A large randomised multicentre trial is needed to compare the relative merits of intravenous thrombolytic treatment in a local hospital with primary angioplasty after transfer in selected high risk patients with acute myocardial infarction.

Keywords: myocardial infarction;  coronary angioplasty;  reperfusion     

Endoluminal vessel reconstruction by stent placement in patients with obstructive coronary artery disease who are poor surgical candidates

Objective—To investigate the safety and efficacy of endoluminal vessel reconstruction by intracoronary stenting in patients with single or multivessel disease who have been turned down for surgical revascularisation.
Design—An observational, single centre trial of consecutive patients being followed up clinically.
Setting—Tertiary referral centre.
Patients—43 patients treated between 1995 and 1996 with a clinical follow up period of at least six months.
Main outcome measures—Acute procedural success following intervention (defined as a residual stenosis of < 30% with normal antegrade flow and without acute clinical complications); major adverse clinical events (death, myocardial infarction, repeat intervention, clinical restenosis); and functional status during follow up.
Results—Acute procedural success was achieved in 39 patients. Failures resulted from a refractory no reflow phenomenon with Q wave myocardial infarction (two patients), and from subacute stent thrombosis (one patient) and saphenous vein graft rupture at stent site (one patient), both manifesting by non-Q wave myocardial infarction. During a follow up period of 17 (8) months (mean (SD)), three of these patients died. Clinical restenosis was treated by repeat percutaneous intervention in 11 patients, while 28 patients remained asymptomatic. On a Kaplan-Meier estimate, the proportion of patients without adverse clinical events at two years was 65%.
Conclusions—Percutaneous reconstruction of diseased coronary arteries in patients with single or multivessel disease turned down for surgical revascularisation may be considered as a valuable treatment option. On follow up, more events seem to be encountered than after elective de novo stenting of discrete coronary lesions. This is probably related to higher clinical restenosis rates.

Keywords: coronary artery disease;  stents;  restenosis     

Psychological distress among recipients of Björk-Shiley convexo-concave valves: the impact of information

Objective—To establish whether there is more psychological distress among recipients of Björk-Shiley convexo-concave (BScc) valves than among recipients of other valves not known to fracture.
Design—Cross sectional study.
Patients—137 patients who received either a BScc valve or a Sorin Biomedical spherical valve during a randomised trial between 1982 and 1983 at St Antonius Hospital, Nieuwegein. Systematic notification of the risk of strut fracture in recipients of BScc valves was carried out at St Antonius Hospital in 1991.
Mean outcome measures—Psychological distress as assessed with the General Severity Index from the Symptom Checklist 90. 
Results—Psychological distress between recipients of BScc and Sorin valves did not differ irrespective of whether the recipients knew their valve type. More recipients of BScc valves, however, knew their valve type and of problems associated with artificial heart valves.
Conclusions—Information about an increased risk of strut fracture does not induce psychological distress among well informed recipients of BScc valves. All recipients of heart valves should be systematically informed about their valve type—for example, by issuing data cards with valve serial numbers and other relevant information.

Keywords: psychological distress;  artificial heart valves;  Björk-Shiley valves     

Change in ST segment elevation 60 minutes after thrombolytic initiation predicts clinical outcome as accurately as later electrocardiographic changes

Objective—To compare prospectively the prognostic accuracy of a 50% decrease in ST segment elevation on standard 12-lead electrocardiograms (ECGs) recorded at 60, 90, and 180 minutes after thrombolysis initiation in acute myocardial infarction.
Design—Consecutive sample prospective cohort study.
Setting—A single coronary care unit in the north of England.
Patients—190 consecutive patients receiving thrombolysis for first acute myocardial infarction.
Interventions—Thrombolysis at baseline.
Main outcome measures—Cardiac mortality and left ventricular size and function assessed 36 days later.
Results—Failure of ST segment elevation to resolve by 50% in the single lead of maximum ST elevation or the sum ST elevation of all infarct related ECG leads at each of the times studied was associated with a significantly higher mortality, larger left ventricular volume, and lower ejection fraction. There was some variation according to infarct site with only the 60 minute ECG predicting mortality after inferior myocardial infarction and only in anterior myocardial infarction was persistent ST elevation associated with worse left ventricular function. The analysis of the lead of maximum ST elevation at 60 minutes from thrombolysis performed as well as later ECGs in receiver operating characteristic curves for predicting clinical outcome.
Conclusion—The standard 12-lead ECG at 60 minutes predicts clinical outcome as accurately as later ECGs after thrombolysis for first acute myocardial infarction.

Keywords: myocardial infarction;  thrombolysis;  ST segment elevation     

von Willebrand factor, tissue plasminogen activator, and dehydroepiandrosterone sulphate predict cardiovascular death in a 10 year follow up of survivors of acute myocardial infarction

Background—Haemostasis plays a major part in the process initiating a myocardial infarction. The impact of haemostatic variables on long term prognosis is unknown.
Objective—To evaluate von Willebrand factor (vWF), tissue plasminogen activator antigen (t-PA) and its activity before and after venous occlusion, plasminogen activator inhibitor (PAI-1), dehydroepiandrosterone sulphate (DHEAS), and established clinical risk factors as long term predictors for reinfarction and mortality.
Patients—123 consecutive survivors of myocardial infarction followed up for 10 years.
Design—Study entry took place between 1982 and 1983. Fifty seven patients died (54 of cardiovascular disease) during the mean observation time of 10 years.
Results—Cox's univariate regression analysis showed that cardiovascular mortality was significantly associated with age, hypertension, previous history of angina pectoris, DHEAS, mass concentration of t-PA, and vWF. These associations were significant for vWF and mass concentration of t-PA after adjusting for age and hypertension.
Conclusions—A low concentration of DHEAS and high levels of the endothelially derived haemostatic variables vWF and mass concentration of t-PA are predictors of cardiovascular mortality in survivors of myocardial infarction. This association is independent of established clinical risk factors for mass concentration of t-PA and vWF.

Keywords: myocardial infarction;  risk factors;  fibrinolysis;  tissue plasminogen activator;  plasminogen activator inhibitor;  von Willebrand factor;  dehydroepiandrosterone sulphate     

S-Nitrosoglutathione inhibits platelet activation and deposition in coronary artery saphenous vein grafts in vitro and in vivo

Objective—To investigate platelet activation and deposition in human saphenous vein and internal mammary artery grafts following coronary artery bypass in vitro and in vivo, as well as inhibition of activation by the platelet selective nitric oxide donor S-nitrosoglutathione (GSNO).
Design—Controlled in vitro and in vivo studies.
Setting—Tertiary cardiac centre.
Patients—24 patients undergoing coronary artery bypass surgery requiring vein and artery grafts.
Interventions—In vitro: human platelet rich plasma was perfused through segments of vein and artery, with or without GSNO 10^-6 M, and the platelet count was measured in the effluent. In vivo: indium-111 labelled antibody against the platelet α granule protein GMP-140 was injected at the end of coronary bypass grafting and γ counts were compared between vein and artery grafts with or without systemic infusion of GSNO (40 nmol/min).
Results—In vitro: platelet count in perfused vein (< 70% of baseline) decreased more than in artery segments (89-94% of baseline) (p < 0.001). The platelet count was unchanged with GSNO in vein and artery segments. In vivo: γ counts were greater at all time points over vein than artery grafts (p < 0.05), and were reduced by infusion of GSNO (p < 0.05).
Conclusions—Platelet activation is greater in vein than in artery grafts in vitro and in vivo. Activation, which contributes to early vein graft failure, was inhibited by GSNO.

Keywords: coronary artery bypass surgery;  platelet activation;  S-nitrosoglutathione;  ischaemic heart disease     

Direct current cardioversion does not cause cardiac damage: evidence from cardiac troponin T estimation

Aim—To determine whether elective direct current (dc) cardioversion of atrial fibrillation/flutter causes myocardial damage.
Methods and results—Cardiac troponin T and creatine kinase were estimated 20-28 hours after dc cardioversion in 51 patients who received dc shocks for elective cardioversion of chronic atrial fibrillation/flutter. Although creatine kinase was raised in 44 patients, cardiac troponin T was undetectable in all patients.
Conclusion—Cardiac damage does not occur as a result of cardioversion.

Keywords: cardioversion;  troponin T;  creatine kinase;  atrial fibrillation