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M Dellborg

Publications and source records attributed to M Dellborg.

At least 55 records · Page 3Linked to original sources

[Continuous ECG monitoring. A valuable technique in acute myocardial infarction].

Early diagnosis of acute myocardial infarction is important to enable myocardial injury to be limited by means of various treatments. Monitoring of vessel patency with vector cardiography or continuous 12-lead ECG recording is a form of surveillance that has been widely accepted in Sweden. In post-reperfusion therapy monitoring, there is approximately 80 per cent agreement between monitoring ST-segment changes and acute coronary cardiography. For risk stratification of patients with unstable angina or non-Q-wave infarction, ST-segment monitoring manifests great predictive power which is further enhanced by its combination with the measurement of highly specific markers of myocardial injury. Computerised techniques for continuous monitoring of multiple ECG leads have contributed much to our understanding of the dynamics of acute coronary heart disease. Valuable prognostic information is available in real time, early identification of myocardial injury is possible, and treatment strategies can be based upon more reliable grounds.

Electrocardiography, Ambulatory↗

Heparin is more effective than inogatran, a low-molecular weight thrombin inhibitor in suppressing ischemia and recurrent angina in unstable coronary disease. Thrombin Inhibition in Myocardial Ischemia (TRIM) Study Group.

Thrombin has been suggested as one of the main pharmacologic targets in unstable coronary syndromes. Electrocardiographic signs of ischemia during continuous monitoring convey prognostic information in these patients. This study assessed the anti-ischemic and clinical effects of the novel low-molecular weight thrombin inhibitor inogatran in patients with unstable angina and non-Q-wave infarction without persistent ST-segment elevation on hospital admission. Within 24 hours of the last episode of chest pain, 324 patients were randomized to 72 hours of treatment with inogatran or heparin. Continuous ST-segment analysis with computerized vectorcardiography was used to monitor ischemia for 24 hours. The occurrence of cardiac events during the first 7 days were studied and compared with ischemic episodes during the initial 24 hours. The heparin-treated patients had less episodes of ischemia (ST vector magnitude [ST-VM]: 1 +/- 2.6 vs 2 +/- 4.5, p < 0.001 and ST change vector magnitude [STC-VM]: 3 +/- 4.7 vs 6 +/- 7.6, p < 0.001) than the patients receiving inogatran. This was paralleled by a lower incidence of the combined end point of death, nonfatal infarction, refractory or recurrent angina during the first 7 days for the heparin-treated patients (35%) compared with the inogatran-treated patients (50%) (p < 0.05). Patients who had episodes of ischemia in spite of anti-ischemic therapy were at increased risk of all events studied. Heparin is more effective than inogatran in suppressing myocardial ischemia and clinical events at short-term follow-up. Continuous ST-segment monitoring with vectorcardiography identifies nonresponders who are at an increased level of risk.

Adult↗

Occurrence, characteristics, and outcome of patients hospitalized with a diagnosis of acute myocardial infarction who do not fulfill traditional criteria.

BACKGROUND: The diagnosis of acute myocardial infarction (AMI) is traditionally based on clinical history, elevation of serum enzyme activity, and typical changes in the electrocardiogram (ECG); however, not all patients who develop AMI fulfill these criteria on discharge from hospital. HYPOTHESIS: The aim of the study was to evaluate (1) the frequency with which the traditional criteria for AMI are not fulfilled among patients diagnosed with AMI on discharge, and (2) whether patients with and without these criteria differ in terms of characteristics, treatment, and outcome. METHODS: All patients aged < 75 years and hospitalized in the municipality of Göteborg with a discharge diagnosis of AMI were included. Fulfillment criteria for AMI were two of the following three points: (1) chest pain, (2) increase in cardiac enzymes, and (3) development of Q waves. RESULTS: In all, 1,188 admitted patients, 27% of whom were women, were included in the analysis. Of these, 193 (16%) did not fulfill the traditional criteria for AMI. These patients had an in-hospital mortality rate of 48%; of these, 59% died a sudden death, and of those who were autopsied (62%), 96% showed signs of a fresh AMI. The most common symptom on admission to hospital in patients who did not fulfill the traditional criteria was chest pain (34%), followed by dyspnea (27%) and fatigue (14%). Of those who died suddenly, fewer than half had been admitted to the coronary care unit. CONCLUSION: Patients diagnosed with AMI who do not fulfill the traditional diagnosis criteria have high mortality. On admission to hospital, the initial suspicion of AMI is often vague. Measures for earlier detection of life-threatening coronary artery disease among these patients are warranted.

Adult↗

Improved long-term prognosis after myocardial infarction 1984-1991.

AIMS: We set out to examine whether long term prognosis in terms of 2-year mortality after myocardial infarction has improved after the introduction of intravenous beta-blockers, nitroglycerin infusion, aspirin and thrombolytics, in an unselected population of patients hospitalized with a myocardial infarction. METHODS AND RESULTS: We investigated retrospectively 3791 acute myocardial infarctions in 3187 Göteborg women and men (1039 women and 2148 men), who were consecutively admitted to the coronary care unit at the Ostra hospital during 1984-1991. Throughout this period, data were entered continuously into the coronary care unit database. Mortality data were collected through the Swedish cause-specific mortality register. The primary end-point was mortality within 2 years after the onset of the index infarction. Two-year mortality decreased from 36% in 1984 to 25% in 1991. In a Cox regression model (including myocardial infarctions up to 1993) year of hospitalization, age, diabetes mellitus, sex, prior myocardial infarction and indeterminable infarct location all had a significant impact on survival after myocardial infarct. Thrombolytic therapy and hypertension had no prognostic significance. CONCLUSION: Against a background of radical changes in the treatment of acute myocardial infarction during 1984-1991 we have seen decreasing in-hospital mortality as well as a substantial decrease in 2-year mortality.

Aged↗

One-year mortality after acute myocardial infarction prior to and after the implementation of a widespread use of thrombolysis and aspirin. Experiences from the community of Göteborg, Sweden.

UNLABELLED: During 1 year of follow-up, we compared the mortality after acute myocardial infarction (AMI) prior to and after the introduction of a more widespread use of thrombolytic agents and aspirin. STUDY PERIOD: Two periods (I = 1986-1987 and II = 1989-1990) were compared. PATIENTS: All patients admitted to the coronary care units at the two city hospitals in the community of Goteborg who fulfilled the criteria for development of AMI participated in the evaluation. RESULTS: The overall 1-year mortality rate was 27% [corrected] during period I and 23% during period II (NS). However, among patients up to 70 years of age, the mortality was reduced from 15 to 11% (p < 0.05), whereas among patients aged over 70 years the mortality remained almost unchanged (34 vs. 35%; NS). CONCLUSION: The introduction of a more widespread use of thrombolytic agents and aspirin has not substantially changed the overall mortality in AMI. However, among younger patients, the mortality appears to have been reduced but not among the elderly.

Aged↗

Diagnosis of acute myocardial infarction in patients with chronic right bundle-branch block using standard 12-lead electrocardiogram compared with dynamic vector cardiography.

The aim of the study was to evaluate standard 12-lead electrocardiogram (ECG) criteria and to compare them with dynamic vector cardiography in patients with chronic right bundle-branch block for diagnosing acute myocardial infarction. We used standard 12-lead ECGs recorded on admission and after 12-24 h and compared them with dynamic vector cardiography with trend analysis during the first 12 h. In patients with right bundle-branch block, ST segment changes occurred in the same way as for patients with narrow QRS complexes. By adding 4 h of continuous vector cardiographic monitoring we were able to identify patients with acute myocardial infarction with a high diagnostic accuracy.

Aged↗

Key factors in the identification of the high-risk patient with unstable coronary artery disease: clinical findings, resting 12-lead electrocardiogram, and continuous electrocardiographic monitoring.

This article reviews a range of methods for identifying high-risk patients with unstable coronary artery disease, including clinical evaluation, the resting 12-lead electrocardiogram, continuous vectorcardiography, and a combined risk evaluation using continuous vectorcardiography and measurement of troponin-T. Clinical evaluation is not very accurate for identifying high-risk patients and modern techniques have not been fully validated in clinical trials. The combination of continuous vectorcardiography and biochemical monitoring is a very powerful method of identifying both very high- and very low-risk patients and may be increasingly used in the future.

Biomarkers↗

Comparison of medical care and one- and 12-month mortality of hospitalized patients with acute myocardial infarction in Minneapolis-St. Paul, Minnesota, United States of America and Göteborg, Sweden.

We compared medical care and mortality through 1-year of hospitalized acute myocardial infarction (AMI) patients in 2 large metropolitan areas in the United States and Sweden. All hospitalized AMI discharges (International Classification of Diseases, 9th revision [ICD9] codes 410) occurring among 30 to 74-year-old residents of the Minneapolis-St. Paul metropolitan area in 1990 and Göteborg, Sweden, in 1990 to 1991 were identified and their medical records examined. There were dramatic differences in medical care during the index hospitalization of AMI patients between Minneapolis-St. Paul and Göteborg. Use of thrombolytic therapy, coronary angioplasty, bypass surgery, calcium antagonists and lidocaine was more common in Minneapolis-St. Paul; beta blockers were more frequently used in Göteborg, and aspirin use was similar. Despite these large differences, neither 28-day nor 1-year mortality of hospitalized AMI patients differed significantly. The marked differences found in the early treatment of AMI between Minneapolis-St. Paul and Göteborg, combined with the negligible differences observed in short- and long-term mortality, raise questions about the most effective and efficient allocation of medical resources.

Adult↗

Continuation of CPR on admission to emergency department after out-of-hospital cardiac arrest. Occurrence, characteristics and outcome.

AIM: To describe the occurrence, characteristics and outcome among patients with out-of-hospital cardiac arrest who required continuation of cardiopulmonary resuscitation (CPR) on admission to the emergency department. PATIENTS: all patients in the municipality of Göteborg who suffered out-of-hospital cardiac arrest, were reached by the emergency medical service (EMS) system and in whom CPR was initiated. Period for inclusion in study: 1 Oct. 1980-31 Dec. 1992. RESULTS: of 334 out-of-hospital cardiac arrests, 2,319 (68%) were receiving on-going CPR at the time of admission to hospital. Of these, 137 patients (6%) were hospitalized alive and 28 (1.2%) could be discharged from hospital. Of these patients, 39% had a cerebral performance categories (CPC) score of 1 (no cerebral deficiency), 18% had a CPC score of 2 (moderate cerebral deficiency), 36% had a CPC score of 3 (severe cerebral deficiency) and 7% had a CPC score of 4 (coma) at discharge. Among patients discharged. 76% were alive after 1 year. CONCLUSION: among consecutive patients with out-of-hospital cardiac arrest, CPR was ongoing in 68% of them on admission to hospital. Among these patients, 6% were hospitalized alive and 1.2% were discharged from hospital. Thus, among patients with ongoing CPR on admission to hospital, survivors can be found but they are few in numbers and extensive cerebral damage is frequently present.

Adolescent↗

Non-invasive risk stratification within 48 h of hospital admission in patients with unstable coronary disease.

AIMS: In this study we evaluated the prognostic value of three methods of early risk estimation in patients with unstable coronary disease. METHODS AND RESULTS: The methods evaluated were: clinical risk estimation at hospital admission, continuous ST analysis with computerized vectorcardiography for 24 h and serial measurements of creatinine kinase-MB for 48 h. Twenty-seven (14%) of the 195 patients died or had a non-fatal infarction within one year. Clinical risk evaluation correctly identified a subgroup of patients with low risk but did not otherwise predict outcome. Fifty-six (29%) patients had ST vector magnitude episodes on vectorcardiography, 70 (38%) had three or more episodes of ST change vector magnitude and 74 (38%) had a peak creatinine kinase-MB value of 6 microgram.l-1 or more. The even rate for patients with ST vector magnitude episodes (23%) was significantly higher than for those without (10%; P < 0.05). For patients with and without three or more episodes of ST change vector magnitude the event rate was 23% and 9% respectively (P < 0.05) and for patients with and without creatinine kinase-MB > or = 6 microgram.l-1 the event rate was 23% and 8% respectively (P < 0.01). The positive predictive value of having none, either one or both of the ST or creatinine kinase-MB markers positive was incremental. CONCLUSION: Continuous vectorcardiographic monitoring of ischaemia in combination with serial creatinine kinase-MB measurement considerably improves risk stratification in unstable coronary disease.

Adult↗

Vectorcardiographic monitoring of patients with acute myocardial infarction and chronic bundle branch block.

AIMS: This study was set up to describe vectorcardiographic patterns in patients with bundle-branch block and acute myocardial infarction. METHODS AND RESULTS: Sixty-five patients admitted to the coronary care unit with bundle-branch block and suspected acute myocardial infarction were monitored by dynamic vectorcardiography with trend analysis. In 28 patients, a clinical diagnosis of acute myocardial infarction was made. In patients with left bundle-branch block and acute myocardial infarction, the pattern of QRS vector-difference evolution was similar to that in patients with the narrow QRS complex, while ST vector-magnitude changes increased over time. Using a cut-off value for QRS vector-difference at 12 h of more than 20 microVs and a specific trend curve pattern, acute myocardial infarction in the presence of left bundle-branch block could be diagnosed with an accuracy of 71%. For patients with right bundle branch block, using a maximum ST vector-magnitude of > 200 microV during the first 4 h, acute myocardial infarction could be diagnosed with a 78% accuracy. CONCLUSION: Our results indicate that dynamic vectorcardiography is a valuable tool in diagnosing and monitoring acute myocardial infarction in patients with bundle branch block.

Aged↗

Nucleoside transport inhibition by draflazine in unstable coronary disease.

OBJECTIVES: In a randomised, double-blind, placebo controlled study, we evaluated the tolerability and safety of draflazine, a nucleoside transport inhibitor, in the treatment of patients with unstable angina and non-Q-wave infarction. METHODS: Twenty-one patients were randomised to treatment with draflazine 3.5 mg or matching placebo given as an i.v. infusion and haemodynamic and symptomatic tolerability were investigated. Myocardial ischaemia was evaluated by means of vectorcardiography and blood analysis of the MB fraction of creatine kinase. RESULTS: The study drug was well tolerated by all patients and it did not cause any adverse haemodynamic effects, nor other serious adverse events. Three patients in the placebo group reported five adverse events, as compared to a single adverse event in the draflazine group. Cardiovascular events were detected in 7 patients in the placebo group and in 5 patients receiving draflazine. The mean duration of chest pain during the 24 hour observation period was 91.4 min in the placebo group compared to 75.5 min in draflazine treated patients. Neither the vectorcardiographic nor biochemical measures of ischaemia differed between treatment groups. CONCLUSION: Nucleoside transport inhibition by draflazine was well tolerated by patients with unstable coronary disease. It seems to be a promising method of adenosine enhancement in acute myocardial ischaemia. The potential cardioprotective effect of the drug needs further evaluation in larger trials.

Aged↗

Thrombin inhibition with inogatran for unstable angina pectoris: evidence for reactivated ischaemia after cessation of short-term treatment.

BACKGROUND: The acute coronary syndromes of unstable angina and non-Q-wave infarction are initiated by coronary plaque rupture and subsequent thrombus formation. Thrombin is central to this response as it activates platelets and the coagulation system. In an open design study we assessed the tolerability and safety of the low molecular weight thrombin inhibitor, inogatran, for unstable angina or non-Q-wave infarction. METHODS: Thirty-seven patients, treated within 72 h of symptoms, were allocated consecutively to groups to receive a 4 h infusion with one of three doses of inogatran. Thrombin generation and activity were measured with plasma markers at baseline, after the 4 h treatment period and 4 h later. Ischaemia was monitored using continuous vectorcardiography during the 4 h of treatment and during the subsequent 4 h after inogatran infusion had been stopped, to detect any increase in ischaemic events after the period of treatment. In addition, 12 patients received inogatran as an infusion for 72 h. RESULTS: Inogatran was tolerated well. There were no adverse haemodynamic effects or allergic reactions. Minor bleeding events were detected in 37% of the patients. The biochemical and vectorcardiographic findings indicated suppression of thrombin generation after the 4 h treatment period compared with baseline. During the first 4 h after inogatran treatment, thrombin activity and episodes of ischaemia were increased compared with during the treatment period. CONCLUSION: Inogatran was tolerated well and was safe, but its discontinuation was followed by a reactivation of thrombin activity and ischaemia. Whether this reactivation represented a rebound phenomenon, or merely resulted from the discontinuation of an effective therapy, cannot be established from the present study.

Adult↗

Ischaemia detected by continuous on-line vectorcardiographic monitoring predicts unfavourable outcome in patients admitted with probable unstable coronary disease.

BACKGROUND: Several methods have been suggested for risk stratification of patients with unstable coronary syndromes. However, most of these are applied several days after hospital admission. METHODS: In this study we investigated the prognostic value of continuous ST-segment and QRS vector monitoring with computerized vectorcardiography (VCG), serial measurements of creatine kinase isoenzyme MB (CK-MB), predischarge stress testing and baseline data in patients with unstable angina pectoris or non-Q-wave infarction. RESULTS: During the 24 h VCG monitoring, 56 (29%) of the 195 patients had ST-vector magnitude (ST-VM) episodes of ischaemia. Seventy-four (38%) patients had a peak CK-MB value of 6 micrograms/l or higher during the 48 h sampling period. Several discrete variables were associated with death or non-fatal infarction at 1 year of follow-up in an univariate analysis. Among these were age > or = 65 years, female sex, St depression on the admission ECG or VCG monitoring, and elevated CK-MB levels, but neither the occurrence, duration nor intensity of chest pain. With Cox's proportional hazards regression analysis, ST-VM episodes on VCG monitoring were identified as independent markers of the risk of death (P = 0.013), death or non-fatal infarction (P = 0.035) and death, non-fatal infarction, unstable angina during the first year, or revascularization before hospital discharge (P = 0.005). CONCLUSIONS: VCG monitoring of ischaemia provides independent prognostic information in unstable angina. High-risk patients can easily be identified within 24 h of hospital admission. Whether early intervention based on these criteria will result in improved prognosis remains to be shown in future studies.

Adult↗

Dynamic vectorcardiography for early diagnosis of acute myocardial infarction compared with 12-lead electrocardiogram. BIOMACS Study Group.

BACKGROUND: The aim of the study was to assess the diagnostic accuracy of multilead continuous vectorcardiography (VCG) for early diagnosis of acute myocardial infarction (AMI) in patients admitted to hospital because of suspicion of AMI. VCG was compared with resting 12-lead electrocardiogram (ECG) on admission. METHODS: In a multicentre study, 107 patients with chest pain (< or = 12 h) were included. The diagnosis of AMI was on the basis of World Health Organization criteria. Continuous VCG was recorded for 12-24 h and the data were evaluated blindly at 2 and 6 h of recording and after the completion of recording (12-24 h). RESULTS: AMI was diagnosed in 74 patients. The VCG recording had a diagnostic accuracy of 71% after 2 h and 86% after both the 6 h and the completed VCG recording. Compared with ECG on admission, the VCG recording after 6 h showed a significantly greater sensitivity: 86% compared with 62% (P < 0.01). In patients with non-diagnostic ECG on arrival (n = 55), VCG after 6 h had a diagnostic accuracy of 85%, a sensitivity of 82% and a specificity of 89%. CONCLUSIONS: VCG might be useful for early diagnosis of AMI, especially in patients with non-diagnostic ECG.

Electrocardiography↗

Ridogrel as an adjunct to thrombolysis in acute myocardial infarction.

An open pilot study was performed to assess the safety and preliminary efficacy of ridogrel, a selective thromboxane-A2 synthetase inhibitor and thromboxane-A2/prostaglandin endoperoxide receptor blocker, as adjunct to thrombolysis, with alteplase and heparin. In 50 patients with acute myocardial infarction, 300 mg ridogrel was injected intravenously in addition to alteplase and heparin. Ridogrel was continued orally (300 mg) twice daily for 5 days. Patency rate at initial (90 min) angiography, defined as thrombolysis in myocardial infarction perfusion grades 2 or 3, was 86%. Rescue percutaneous transluminal coronary angioplasty was performed in 10 patients; immediate results were good in nine, while a large dissection occurred in one patient. New ischemia occurred in 10 patients within 24 h, and after the second angiogram in seven cases. Three underwent coronary artery bypass grafting and seven percutaneous transluminal coronary angioplasty without further complication. Patency rate at second angiography (between 6 and 24 h) was 94%. New Q-waves appeared in 56% of the patients; 36% had a non-Q-wave infarction and 8% had no enzyme rise. Enzymatic infarct size, estimated by the cumulative quantity of alpha-hydroxybutyrate dehydrogenase released in 72 h, was substantially smaller than in comparable studies with rt-PA and heparin. One patient died due to a cerebrovascular hemorrhage. No other deaths occurred. Bleeding complications were seen in 18 patients (36%), necessitating blood transfusion in three. Reinfarction did not occur. Eventually 49 patients were discharged in good condition. Safety with regard to bleeding complications of ridogrel in conjunction with alteplase is about the same as that of aspirin. Immediate and late patency rates were high. Rescue percutaneous transluminal coronary angioplasty could be performed with relative safety and early reocclusion could be successfully dealt with by repeat percutaneous transluminal coronary angioplasty. Further studies with this or similar compounds seem warranted.

Adult↗

Dynamic on-line vectorcardiography improves and simplifies in-hospital ischemia monitoring of patients with unstable angina.

OBJECTIVES: This study sought to validate computerized vectorcardiography against the established technique of Holter electrocardiographic (ECG) monitoring and to compare the feasibility of the two methods for monitoring patients with unstable angina pectoris. BACKGROUND: Detection of myocardial ischemic episodes is an important objective in patients admitted to the hospital for unstable angina pectoris. Standard ECG monitoring may be sufficient for detection of symptomatic episodes but will often overlook silent ischemia. Holter ECG monitoring has a higher likelihood of discovering such episodes, but analysis is time-consuming, and the results are not available on-line. METHODS: We simultaneously monitored 53 consecutive patients with unstable angina, 46 of whom had technically adequate 24-h Holter ECGs and computerized vectorcardiograms. RESULTS: The Holter tapes had a mean (+/- SD) of 15.3 +/- 10.3 h of recording with both channels technically adequate for analysis compared with 23.7 +/- 1.77 h of vectorcardiographic recording that could be analyzed (p < 0.01). Of the 15 symptomatic episodes detected by Holter ECG monitoring, 13 were also detected with dynamic vectorcardiography. In contrast, eight patients had 18 episodes of chest pain, with simultaneous ST segment changes detected by dynamic vectorcardiography; only 9 of these episodes were also detected by Holter ECG monitoring. CONCLUSIONS: Monitoring of myocardial ischemia with dynamic vectorcardiography seems to be more efficient than Holter monitoring and may have a higher sensitivity. Computerized, continuous vectorcardiography has a complete real-time capacity, allowing monitoring over prolonged periods of time, and the results are immediately available without time-consuming analysis.

Adult↗