Search PubMed⌕ Search

Biomedical subjects

M Dellborg

Publications and source records attributed to M Dellborg.

At least 73 records · Page 4Linked to original sources
PubMed1995

Vectorcardiographic monitoring to assess early vessel patency after reperfusion therapy for acute myocardial infarction.

Reperfusion therapy has lowered mortality in patients suffering from acute myocardial infarction. Failure to reperfuse is associated with an increased short- and long-term mortality. In a prospective study we used dynamic vectorcardiography to monitor 96 patients with acute myocardial infarction treated with reperfusion therapy to non-invasively assess coronary patency. The results from continuous monitoring were compared to those obtained from angiography. By using trend-analysis of QRS vector difference and ST vector magnitude, we were able to correctly identify 58 of the 70 patients (83%) with a reperfused infarct-related artery, and 19 of the 26 patients (73%) with a persistently occluded artery demonstrated at an early angiogram (diagnostic accuracy 80%). In patients with high-grade collateral flow to the infarct-related area, the results of the vectorcardiographic monitoring and of angiography showed the largest disagreement, whereas the accuracy of vectorcardiographic monitoring was high: 88% among patients without collaterals. The present results suggest that QRS complex and ST segment vectorcardiographic monitoring is a useful tool for assessing early coronary artery patency, and that dynamic vectorcardiography may help in identifying candidates for emergency coronary angiography.

Acute Disease↗
PubMed1995

Diagnostic accuracy of physicians for identifying patients with acute myocardial infarction without an electrocardiogram. Experiences from the TEAHAT Trial.

AIM: To determine the diagnostic accuracy of physicians for identifying patients with acute myocardial infarction (AMI) without an electrocardiogram (ECG). PATIENTS: All patients in Göteborg with suspected AMI below 75 years of age who called for an ambulance or came directly to one of the two city hospitals with a delay time of less than 2 h 45 min from the start of symptoms. METHODS: As part of the TEAHAT study (comparing rt-PA and placebo in AMI), we asked physicians to judge on a 1-5 scale (1 = no suspicion; 5 = convinced) how strong their suspicion of AMI was prior to interpreting the ECG. RESULTS: Among patients evaluated outside hospital with 4 or 5 on the scale, i.e. either a strong suspicion of AMI or the physician felt convinced about the diagnosis, 45% had ST elevation and 48% developed AMI during the first 3 days in hospital. The corresponding values for patients evaluated in hospital were 67 and 70%, respectively. CONCLUSION: We found that physicians could not accurately distinguish patients with AMI from those without based on clinical criteria without the help of an ECG.

Acute Disease↗
PubMed1995

Optimal treatment after acute myocardial infarction in the elderly.

Elderly patients with acute myocardial infarction (AMI) more often have a previous history of cardiovascular disease than do younger patients. Furthermore, they less frequently present with typical symptoms and a typical electrocardiogram pattern. Whereas age is the most important predictor for mortality after AMI, the relationship between age and morbidity is more complex. Treatment of elderly patients with AMI is very similar to treatment of younger patients. However, the risk of intolerability to various drugs increases with age, and in many instances doses have to be adjusted. In many trials, the number of lives saved with various interventions seem, if anything, to be more numerous among the elderly. However, it should be remembered that experience with various treatments in the elderly (patients aged > 80 years) is limited. Whether experiences with people aged up to 80 years can be extrapolated to higher age groups is debatable. With increasing age, there is an increased frequency of other disabling diseases, as well as generalised atherosclerosis. It might very well be that even in the elderly it is possible to relieve symptoms and improve morbidity, even though the effects on the prognosis are likely to be less marked.

Aged↗
PubMed1994

ECG changes during myocardial ischemia. Differences between men and women.

Women have a higher short-term mortality in acute myocardial infarction (MI) compared with men. This may be partly explained by differences in risk factors such as age and diabetes. However, several reports have focused on the occurrence of a sex bias making women less likely to be subjected to angiography and revascularization as well as aggressive pharmacologic treatment of acute MI. The decision to initiate these procedures is often based on ischemic changes of the electrocardiogram. It was therefore investigated whether differences between men and women in magnitude of electrocardiographic changes during myocardial ischemia could explain some of the differences previously reported. A total of 178 patients with chest pain suggestive of MI (135 men and 43 women) included in a study of thrombolytics were monitored for 24 hours with continuous vectorcardiography. Also, 81 patients with stable angina pectoris undergoing elective angioplasty were monitored during the procedure. In patients admitted with suspicion of MI, the initial summated ST deviation was 178 +/- 146 microV for men as compared with 105 +/- 91 microV for women (P = .002). During angioplasty, men had significantly more pronounced maximum ST deviation during inflation of the balloon (235 +/- 165 vs 156 +/- 89 microV; P = .036). In conclusion, men have more pronounced ST changes than women during myocardial ischemia. When fixed magnitudes of ST deviation are required for initiating therapy such as thrombolytics, this will favor treatment of men. A sex-adjusted limit for administrating thrombolytic drugs may be warranted in the light of the above findings.

Angioplasty, Balloon, Coronary↗
PubMed1994

Declining hospital mortality in acute myocardial infarction.

Beta-blockers, nitrates, aspirin and thrombolytic drugs have each separately been shown to reduce mortality in acute myocardial infarction, but the effect of these treatments combined during routine coronary care has not been assessed. The coronary care unit at Ostra Hospital services a stable community of 250,000 inhabitants. Since 1984 all patients have been entered into a computerized database. In addition, information on age, sex, discharge diagnosis and hospital outcome is also available for patients admitted between 1979 and 1983. In 1984, routine treatment with intravenous beta-blockers was introduced, to be followed in 1986 by intravenous nitroglycerin and in 1988 by aspirin in all patients without contraindications. Since 1988, intravenous thrombolytic treatment has been also given routinely to all patients with ST-elevation and chest pain < 6 h. Despite a similar number of patients and an increasing median age, the in-hospital mortality has declined from 18.5% in 1979 to 11.8% in 1990 (P < 0.01). It is concluded that mortality from acute myocardial infarction has declined by almost 40% since 1979. This reduction cannot be explained by a single major therapeutic intervention but may be attributed to the combined use of multi-lead monitoring, early use of beta-blockers, nitroglycerin, aspirin and thrombolytic agents.

Adrenergic beta-Antagonists↗
PubMed1994

Addition of sodium to iohexol. A vectorcardiographic study.

The addition of sodium to nonionic contrast media has reduced the incidence of arrhythmias in animal models. The influence on cardiac function and safety of sodium addition to the nonionic contrast medium iohexol (Omnipaque) was studied in a randomized, double-blind trial in patients undergoing cardioangiography. Fifty-nine patients received iohexol 350 mg I/ml with NaCl 28 mmol/l and 58, iohexol only. ECG changes after contrast injections were evaluated with continuous computerized dynamic vectorcardiography (VCG). QRS-vector difference (QRS-vd), which reflects changes in the QRS-complex, was chosen as the main parameter. Both contrast media caused changes in the QRS-complex, but there was no significant difference between the two. No serious arrhythmias were observed. Both contrast media were well tolerated. No beneficial effects from enriching iohexol with sodium were found. VCG was found to be a valuable tool in the study of contrast medium-induced ECG changes.

Adult↗
PubMed1993

Electrocardiographic assessment of infarct size: comparison between QRS scoring of 12-lead electrocardiography and dynamic vectorcardiography.

Myocardial infarct size is one of the most important predictors of prognosis in patients suffering an acute myocardial infarction. It can be assessed by enzymatic and electrocardiographic methods. The present report compares dynamic vectorcardiographic monitoring, serial plasma enzyme activity measurements and QRS scoring according to Palmeri as techniques for infarct size estimation. We report the results from 74 patients with acute myocardial infarction, who participated in a randomized trial of treatment with alteplase. A good correlation was found between myocardial infarct size by estimation from enzymatic measurement and from dynamic vectorcardiography. Dynamic vectorcardiography correlated more closely with enzymatically estimated infarct size in patients with Q-wave infarction, regardless of infarct location, than did QRS scoring of the conventional 12-lead electrocardiogram. Furthermore, dynamic vectorcardiography requires no time-consuming analysis and can be used for on-line monitoring of patients with ongoing infarction to estimate the size of an acute infarction while it is developing.

Clinical Enzyme Tests↗
PubMed1993

Impact of early thrombolysis on chest pain score reflecting myocardial ischemia in relation to various markers of ischemic damage. TEAHAT Study Group.

We randomized 352 patients with pain suggestive of acute myocardial infarction who were seen less than 3 h after onset of symptoms to either tissue plasminogen activator or placebo. The impact of treatment on chest pain score was assessed during the first 24 h and related to limitation of final myocardial damage as assessed by various indirect markers. The most marked effect of tissue plasminogen activator was observed in the chest pain score being reduced by 43% in the tissue plasminogen activator group as compared with placebo. Limitation of infarct size with tissue plasminogen activator reached the following percentage values when various methods were used: maximum serum lactate dehydrogenase I activity, 32%; vectorcardiography (QRS vector difference), 20%; electrocardiography (Palmeri score), 20%; ejection fraction, 9%. We conclude that early thrombolysis in acute myocardial infarction reduces the severity of chest pain by nearly 50%. The effect on chest pain is much more marked as compared with the effect on various markers of the final ischemic damage.

Aged↗
PubMed1993

Acute myocardial infarction: difference in the treatment between men and women.

During the last decade, treatment of myocardial infarction has changed and the prognosis dramatically improved. A sex bias in considering revascularization in men and women with coronary heart disease has been reported. The influence of gender on treatment given to patients with an acute myocardial infarction has not been investigated. From 1989 to 1991 there were 1515 patients with acute myocardial infarction admitted to the coronary care unit at Ostra Hospital; 67% were men. Pharmacological treatment limiting infarct size was given to 60% of all women and to 67% of all men; p < 0.05. In addition, coronary angiography during the hospital stay was performed in 0.2% of all women vs 1.9% of all men; p < 0.05. The prevalence of diabetes, age, symptoms or prehospital delay cannot explain these findings. While a sex bias in referring patients for revascularization has been reported, this report also describes a possible sex bias in the pharmacological treatment of acute myocardial infarction.

Adrenergic beta-Antagonists↗
PubMed1993

Silent myocardial ischemia during coronary angioplasty.

Silent myocardial ischemia is a marker in patients with coronary artery disease identifying those at high risk for subsequent cardiac events. During provoked myocardial ischemia some patients with angina pectoris do not develop chest pain. Are there clinical, angiographic or electrocardiographic differences between patients with chest pain as compared with patients without chest pain during provoked myocardial ischemia? Coronary angioplasty is a well-established method for the treatment of coronary stenosis, but it is also an interesting model for the study of myocardial ischemia as a result of coronary occlusion. We monitored 114 patients with angina pectoris during coronary angioplasty with dynamic, computerized vectorcardiography. During inflation of the balloon 33 of 114 patients had silent ischemia. Patients with silent myocardial ischemia had similar reasons for terminating the preangioplasty exercise test and where on similar anti-ischemic drug regimes. Silent myocardial ischemia was significantly associated with a history of diabetes, presence of collaterals, a history of less severe previous angina and less ST segment changes during angioplasty as compared with patients with painful ischemia. It is suggested that during coronary angioplasty silent ischemia may be caused by a less severe degree of ischemia, possibly as a result of the protective effect of collaterals.

Aged↗
PubMed1993

Early electrocardiographic changes in acute myocardial infarction treated by streptokinase or alteplase: a randomized study with dynamic, multi-lead, electrocardiographic monitoring.

Patients with a patent coronary artery after reperfusion therapy show an increased rate of evolution of QRS changes and of resolution of S-T changes as compared to patients with a persistent occlusion. Dynamic vectorcardiography permits multi-lead monitoring of changes in QRS complex and S-T segment over time. We monitored 150 patients randomized to alteplase or streptokinase for 24 h after admission. Alteplase was associated with significantly more rapid evolution of electrocardiographic changes but also with an increased occurrence of recurrent S-T changes. This may indicate a higher rate of early reperfusion with alteplase but due to recurrent ischemia, an electrocardiographic catch-up is seen with similar extent of myocardial damage observed after 24 h of monitoring.

Aged↗