Recombinant hirudin (lepirudin) for the improvement of thrombolysis with streptokinase in patients with acute myocardial infarction: results of the HIT-4 trial.

OBJECTIVES: The purpose of this study was to compare recombinant hirudin and heparin as adjuncts to streptokinase thrombolysis in patients with acute myocardial infarction (AMI). BACKGROUND: Experimental studies and previous small clinical trials suggest that specific thrombin inhibition improves early patency rates and clinical outcome in patients treated with streptokinase. METHODS: In a randomized double-blind, multicenter trial, 1,208 patients with AMI < or =6 h were treated with aspirin and streptokinase and randomized to receive recombinant hirudin (lepirudin, i.v. bolus of 0.2 mg/kg, followed by subcutaneous (s.c.) injections of 0.5 mg/kg b.i.d. for 5 to 7 days) or heparin (i.v. placebo bolus, followed by s.c. injections of 12,500 IU b.i.d. for 5 to 7 days). A total of 447 patients were included in the angiographic substudy in which the primary end point, 90-min Thrombolysis in Myocardial Infarction (TIMI) flow grade 3 of the infarct-related artery, was evaluated, while the other two-thirds served as "safety group" in which only clinical end points were evaluated. As an additional efficacy parameter the ST-segment resolution at 90 and 180 min was measured in all patients. RESULTS: TIMI flow grade 3 was observed in 40.7% in the lepirudin and in 33.5% in the heparin group (p = 0.16), respectively. In the entire study population the proportion of patients with complete ST resolution at 90 min (28% vs. 22%, p = 0.05) and at 180 min (52% vs. 48%, p = 0.18) after start of therapy tended to be higher in the lepirudin group. There was no significant difference in the incidence of hemorrhagic stroke (0.2% vs. 0.3%) or total stroke (1.2% vs. 1.5%), reinfarction rate (4.6% vs. 5.1%) and total mortality rate (6.8% vs. 6.4%) at 30 days, as well as the combined end point of death, nonfatal stroke, nonfatal reinfarction, rescue-percutaneous transluminal coronary angioplasty and refractory angina (22.7 vs. 24.3%) were not statistically different between the two groups. CONCLUSIONS: Lepirudin as adjunct to thrombolysis with streptokinase did not significantly improve restoration of blood flow in the infarct vessel as assessed by angiography, but was associated with an accelerated ST resolution. There was no increase in the risk of major bleedings with lepirudin compared to heparin.

Characteristics and prognosis of non-participants of a multi-centre trial of long-term anticoagulant treatment after myocardial infarction.

Participants of a randomised trial may differ from eligible non-participants as a result of selection. We studied the distribution of prognostic factors and survival in eligible patients of a multi-centre trial of long-term oral anticoagulant treatment after myocardial infarction. All hospital survivors of myocardial infarction in one participating clinical centre of a multi-centre, randomised, double-blind, placebo-controlled trial of long-term anticoagulant treatment after myocardial infarction were screened for entry criteria. Subsequently, prognostic factors and survival of participants were compared with eligible but not randomised patients. The 350 participants were younger and were more often of male gender and more often smokers compared with 587 non-participants. Non-participants had more frequently suffered a previous myocardial infarction and were treated more often with diuretics and ACE-inhibitors, suggesting a higher proportion of patients with chronic heart failure in this group. Age, previous myocardial infarction and the use of diuretics at discharge were independent predictors of mortality, consent showed no association. Our findings indicate that participants of a clinical trial have a better prognosis during the first years following myocardial infarction compared to eligible non-participants as a result of a higher prevalence of cardiovascular risk factors associated with mortality in the non-participants.

Coexistence of a bradycardia- and tachycardia-dependent bundle branch block.

Aberrant ventricular conduction is a rare phenomenon as compared with the more frequently occurring antrioventricular conduction disturbances. It leads to widening of the QRS complex, which is either due to a complete or functional block in one of the bundle branches or a block within the intramyocardial conduction system itself. Mechanisms that are potentially involved in the genesis of aberrant ventricular conduction are sudden shortening of cycle length (tachycardia-dependent phase III), antegrade block with retrograde concealed conduction, or bradycardia-dependent block (enhanced phase IV). In this paper, we present a patient with aberrant ventricular conduction with the occurrence of a tachycardia-dependent, as well as a bradycardia-dependent bundle branch block, which is an even rarer phenomenon.

Arrhythmogenic right ventricular dysplasia as a possible cause of sudden cardiac death: a case report and clinical review.

Sudden cardiac death can be described as an unexplained natural death due to a cardiac cause. It occurs within a short period, one hour or less, after onset of symptoms in a person without any prior medical history. Among the many causes of unexplained sudden cardiac death, we would like to specifically discuss arrhythmogenic right ventricular dysplasia as a rare cause in otherwise healthy and usually young individuals.

Shoshin beriberi: a rare diagnostic problem.

A 30 year old man with a 15 year history of alcohol abuse presented with symptoms and signs of circulatory shock, severe disturbances of renal and liver functions, and metabolic acidosis. The cardiovascular and metabolic features were attributable to Shoshin beriberi. He recovered completely after treatment with thiamine.

Non-invasive detection of early infarct vessel patency by resolution of ST-segment elevation in patients with thrombolysis for acute myocardial infarction; results of the angiographic substudy of the Hirudin for Improvement of Thrombolysis (HIT)-4 trial.

Aims The purpose of this study was to validate ST segment resolution as a non-invasive marker for patency of the infarct-related artery 90 min after the start of streptokinase therapy in patients with acute myocardial infarction. Methods and Results In the HIT-4 angiographic substudy, 447 patients with acute myocardial infarction or =70% ST resolution (n=70) had a 92% probability of TIMI 2/3 flow, while <30% ST resolution (n=172) was associated with the absence of TIMI 3 flow in 84% of patients. Conclusions Despite fairly good sensitivities and specificities the prediction of infarct vessel patency by ST resolution in the individual patient is limited. However, patients with > or =70% ST resolution are likely to have a patent infarct artery and <30% ST resolution predicts epicardial vessel occlusion or, since persistent ST elevation reflects the existing ischaemic myocardial injury, absence of myocardial perfusion.

Differential effects of tissue plasminogen activator and streptokinase on infarct size and on rate of enzyme release: influence of early infarct related artery patency. The GUSTO Enzyme Substudy.

BACKGROUND: The recent international GUSTO trial of 41,021 patients with acute myocardial infarction demonstrated improved 90-min infarct related artery patency as well as reduced mortality in patients treated with an accelerated regimen of tissue plasminogen activator, compared to patients treated with streptokinase. A regimen combining tissue plasminogen activator and streptokinase yielded intermediate results. The present study investigated the effects of treatment on infarct size and enzyme release kinetics in a subgroup of these patients. METHODS: A total of 553 patients from 15 hospitals were enrolled in the study. Four thrombolytic strategies were compared: streptokinase with subcutaneous heparin, streptokinase with intravenous (i.v.) heparin, tissue plasminogen activator with i.v. heparin, and streptokinase plus tissue plasminogen activator with i.v. heparin. The activity of alpha-hydroxybutyrate dehydrogenase (HBDH) in plasma was centrally analysed and infarct size was defined as cumulative HBDH release per litre of plasma within 72 h of the first symptoms (Q(72)). Patency of the infarct-related vessel was determined by angiography in 159 patients, 90 min after treatment. RESULTS: Infarct size was 3.72 g-eq.1(-1) in patients with adequate coronary perfusion (TIMI-3) at the 90 min angiogram and larger in patients with TIMI-2 (4.35 g-eq.1(-1) or TIMI 0-1 (5.07 g-eq.1(-1) flow (P = 0.024). In this subset of the GUSTO angiographic study, early coronary patency rates (TIMI 2 + 3) were similar in the two streptokinase groups (53 and 46%). Higher, but similar, patency rates were observed in the tissue plasminogen activator and combination therapy groups (87 and 90%). Median infarct size for the four treatment groups, expressed in gram-equivalents (g-eq) of myocardium, was 4.4, 4.5, 3.9 and 3.9 g-eq per litre of plasma (P = 0.04 for streptokinase vs tissue plasminogen activator). Six hours after the first symptoms, respectively 5.3, 6.6, 14.0 and 13.6% of total HBDH release was complete (P < 0.0001 for streptokinase vs tissue plasminogen activator). CONCLUSIONS: Rapid and complete coronary reperfusion salvages myocardial tissue, resulting in limitation of infarct size and accelerated release of proteins from the myocardium. Treatment with tissue plasminogen activator, resulting in earlier reperfusion was more effective in reducing infarct size than the streptokinase regimens, which contributes to the differences in survival between treatment groups in the GUSTO trial.

Autonomic and hemodynamic effects of a new selective dopamine agonist, CHF1035, in patients with chronic heart failure.

Dopamine agonists have been studied in chronic heart failure, but earlier reports with non-selective compounds demonstrated unfavourable long-term effects. CHF 1035 is an orally active, new selective dopamine agonist, primarily activating DA2- and alpha2 receptors, thereby inhibiting norepinephrine release, which may be beneficial in heart failure. We conducted a double-blind, placebo-controlled comparison of CHF 1035 (10 mg/day, n = 20) and placebo (n = 9) in patients with mild to moderate chronic heart failure (left ventricular ejection fraction <0.45). Patients were clinically stable on diuretics and angiotensin converting enzyme inhibitors. Both acute and chronic assessments were made, including plasma neurohormones and 24-hr Holter monitoring for heart rate variability analysis. CHF1035 was generally well tolerated during the study. After 10 days, there were no significant changes between the groups regarding heart rate and blood pressure. Compared to placebo, plasma norepinephrine levels decreased on CHF1035, both in the first 4 hours and after 10 days (p<0.05 between groups). Other neurohormones (natriuretic peptides, renin, aldosteron and endothelin) were not significantly affected. Heart rate variability parameters generally increased on CHF1035, but were unaffected by placebo (p < 0.05 between groups). Short-term treatment with the selective dopaminergic agonist CHF1035 is well tolerated, reduces plasma norepinephrine concentrations and increases heart rate variability in mild chronic heart failure.

Randomised, double-blind trial of intravenous diltiazem versus glyceryl trinitrate for unstable angina pectoris.

The effect of dihydropyridines in patients with unstable angina is discouraging. To find out the effect of the non-dihydropyridine-like calcium-channel blocker diltiazem, a randomised, double-blind trial was conducted comparing diltiazem with glyceryl trinitrate, both given intravenously, in 129 patients with unstable angina. The endpoints were refractory angina or myocardial infarction, individually and as a composite endpoint. Refractory angina alone or together with myocardial infarction occurred significantly less commonly in the diltiazem group. While patients were on the trial drugs the numbers with refractory angina were 6 (10%) in the diltiazem group versus 17 (28%) in the glyceryl trinitrate group (relative risk 0.36, p = 0.02), and the numbers with refractory angina and myocardial infarction were 9 (15%) versus 23 (38%) (relative risk 0.40, p = 0.007). Over 48 h the number were: refractory angina 8 (13%) versus 18 (30%), relative risk 0.45, p = 0.03, and refractory angina and myocardial infarction 12 (20.0%) versus 25 (41%), relative risk 0.49, p = 0.02. Patients in the diltiazem group had better (p < 0.05) event-free survival while taking the drugs. Heart-rate pressure product was reduced significantly only by diltiazem (p < 0.05). The incidence of bradyarrhythmias did not differ significantly. Atrioventricular conduction disturbances occurred in 5 (8%) patients in the diltiazem group but were not seen in the glyceryl trinitrate group (p = 0.03). These disturbances could be reversed by decreasing the dose of the drug or withdrawing it. No temporary pacemakers were required. Headache requiring an analgesic or dose adjustment occurred significantly less in the diltiazem group: 3 (5%) versus 15 (25%), relative risk 0.20 (p < 0.004). These results indicate that intravenous diltiazem, compared with intravenous glyceryl trinitrate, significantly reduces ischaemic events and can be used safely in patients with unstable angina.

Evaluation of the Penàz servo-plethysmo-manometer for the continuous, non-invasive measurement of finger blood pressure.

Blood pressure in the finger was measured by a servo-plethysmomanometer constructed after the design of Penàz, which uses the principle of the unloaded arterial wall. The device contains a photoelectric plethysmograph mounted in an inflatable cuff and an electro-pneumatic transducer to control air pressure in the cuff via a servosystem. Comparison of simultaneous measurements of intra-arterial pressure in the brachial artery was performed on 33 patients suspected of having hypertension. In 12 patients evaluation of the technique could not be carried out due to technical failures or distorted blood pressure wave forms. Results of the remaining 21 patients show a mean underestimation of intra-arterial blood pressure by finger cuff blood pressure of 0.8 kPa (6 mm Hg), both for systolic and diastolic levels. The scatter range of the difference is from 1.9 to -3.5 kPa for systolic and 0.1 to -2.5 kPa for diastolic values. It appears that, although not all technical problems are solved, the Penàz servo-plethysmo-manometer is potentially an elegant method by which to arrive at the fully calibrated wave form of blood pressure in a finger in a non-invasive and continuous fashion.

Long-term follow-up after early intervention with intravenous diltiazem or intravenous nitroglycerin for unstable angina pectoris.

AIMS: In a double-blind randomized trial in unstable angina it was shown that intravenous diltiazem reduced ischaemic events in the first 48 h after inclusion better than intravenous nitroglycerin. The present study was performed to establish the long-term prognosis of the randomized patients, with respect to their initial treatment assignment. METHODS AND RESULTS: One year follow-up data on ischaemic end-points and anti-ischaemic medication were recorded. Results were available for all of the 121 randomized patients. One hundred and sixty-seven primary endpoint events were recorded, of which 54 occurred in the first 48 h and 113 during the follow-up. Survival analysis showed that event-free survival was significantly better in the diltiazem group (45.0%) than in the nitroglycerin group (34.4%), P=0.04. The incidence rate after 48 h and one year for cardiac death are, respectively, 0% and 4.1%. The trend in anti-ischaemic medication was higher in the nitroglycerin group. For beta-blockers, this trend became significant after 12 months (P=0.03). CONCLUSION: These results show that the initial benefit obtained by early treatment with intravenous diltiazem was preserved during the first year after the initial hospitalization, and that, despite the high risk of cardiac events in our population, the overall mortality 12 months after inclusion was low.

Angiographic dose-finding study with r-hirudin (HBW 023) for the improvement of thrombolytic therapy with streptokinase (HIT-SK). Interim results.

To evaluate the efficacy and safety of hirudin, a direct thrombin inhibitor, in patients with acute myocardial infarction, a dose-finding, angiography study was carried out. After a pilot phase in 10 patients treated with a bolus of 0.1 mg.kg-1 and a continuous infusion of 0.06 mg.kg-1.h-1 (dose group I), two doses of hirudin, bolus 0.2 mg.kg-1.h-1 (DG II), and bolus 0.4 mg.kg-1 with 0.15 mg.kg-1.h-1 (DG III) were tested and compared with heparin as an adjunct to streptokinase and aspirin. This interim analysis was mandatory due to puncture-site related bleedings. Early and complete patency was achieved in 30% of 35 heparin patients, in 40% of 10 DG I, in 47% of 58 DG II and in 62% of 14 DG III patients. A dose-response relationship particularly between DG I and DG II, was also observed in the anti-thrombotic activity monitored by the aPTT. Apart from the catheter-related bleedings, there were low rates of serious adverse events.

The Asp9 Asn mutation in the lipoprotein lipase gene is associated with increased progression of coronary atherosclerosis. REGRESS Study Group, Interuniversity Cardiology Institute, Utrecht, The Netherlands. Regression Growth Evaluation Statin Study.

BACKGROUND: Many patients suffering from premature coronary artery disease report a family history for such events. A mutation in a particular gene, which confers susceptibility for atherosclerosis, will be found more frequently in individuals suffering from coronary atherosclerosis than in the general population. We have recently reported the identification of an Asp9 Asn substitution in the lipoprotein lipase (LPL) enzyme. We analyzed the impact of this mutation on the progression of coronary atherosclerosis and the effect of pravastatin in both carriers and noncarriers. METHODS AND RESULTS: All patients were enrolled in the quantitative coronary angiographic clinical trial REGRESS, which studied the impact of pravastatin therapy on coronary atherosclerosis. The Asp9 Asn mutation was identified in 38 of 819 (4.8%) patients. Carriers of the mutation more often had a positive family history of cardiovascular disease and lower HDL cholesterol levels than noncarriers. In the placebo group, carriers showed more progression of coronary atherosclerosis than noncarriers: mean reduction of the minimum obstruction diameter of -0.25 mm versus -0.12 mm (P = .029) and increase of percentage diameter stenosis of 6.4% versus 1.4% (P = .004). Moreover, the adjusted relative risk for a clinical event for carriers was calculated at 2.16 (95% CI, 1.09 to 4.29; P = .027). Although the lipid-lowering effect of pravastatin was attenuated in carriers, it appeared that these patients showed a response similar to noncarriers in terms of less progression of atherosclerosis and event-free survival. CONCLUSIONS: This study shows that heterozygosity for a mutation in the LPL gene, which causes only subtle changes in fasting plasma lipids, may promote the progression of coronary atherosclerosis and diminish clinical event-free survival.

Long-term efficacy of diltiazem controlled release versus metoprolol in patients with stable angina pectoris.

In a randomized, double-blind, multicenter study, the efficacy of diltiazem controlled-release (CR) 120 mg b.i.d. was compared with metoprolol 100 mg b.i.d. in 56 patients with stable exertional angina pectoris. Fifty-one patients (28 receiving diltiazem CR, 23 receiving metoprolol), completed a follow-up period of 8 weeks. Thirty-nine patients (20 receiving diltiazem CR, 19 receiving metoprolol), completed a follow-up period of 32 weeks. Maximal exercise testing was performed at baseline and after 8, 20, and 32 weeks of treatment. Most exercise parameters were not significantly different between the patients on diltiazem CR and those on metoprolol. However, exercise duration was longer and maximal work load was higher in patients on diltiazem CR than in patients on metoprolol, and significant differences were observed at 20 weeks of treatment (p = 0.006 and p = 0.008, respectively). At all times during treatment, heart rate at maximal exercise and rate-pressure product at maximal exercise were significantly lower in the patients treated with metoprolol. In conclusion, monotherapy with diltiazem CR is at least as effective as monotherapy with metoprolol in patients with stable angina pectoris. As compared to metoprolol, diltiazem CR has a minor depressing effect on rate-pressure product, resulting in a favorable effect on exercise duration.