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Hans Mickley

Publications and source records attributed to Hans Mickley.

At least 19 recordsLinked to original sources
PubMed2006

Variation and importance of aspirin resistance in patients with known cardiovascular disease.

AIM: To investigate whether aspirin resistance is a persistent condition, and to evaluate if aspirin resistance affects one-year clinical outcome. METHODS AND RESULTS: Previously we studied 298 patients admitted to hospital with symptoms suggestive of an acute myocardial infarction (MI) despite treatment with aspirin, and 70 patients (23.5%) were aspirin resistant. In the present study, platelet function was reassessed by use of a Platelet Function Analyzer-100 one year later. A total of 187 patients were re-examined, and 17 (9.1%) demonstrated aspirin resistance. Of these 17 patients, 12 also exhibited aspirin resistance at baseline resulting in a 6% (12/187) prevalence of persistent aspirin resistance. A total of 34 patients had changed from aspirin resistant at baseline to aspirin sensitive at follow-up. We found a significant decrease in the prevalence of aspirin resistance from baseline (43%) to follow-up (11%) in patients with MI at baseline (p=0.0018). Furthermore, a significant decrease was found for patients without MI at baseline (20% to 9%, p=0.0009). During follow-up, 17% (12/70) of the patients with aspirin resistance at baseline suffered death, MI or stroke compared to 16% (37/227) of aspirin sensitive patients (p=0.868). CONCLUSION: The prevalence of aspirin resistance varies with the clinical status of the patients, and indeed an acute MI is associated with temporary aspirin resistance. We also found that 6% of patients demonstrate persistent aspirin resistance. The presence of aspirin resistance did not affect one-year clinical outcome.

Aged↗
PubMed2006

Frequency and significance of troponin T elevation in acute ischemic stroke.

Elevated levels of troponin have been reported in patients with acute ischemic stroke. In this prospective study, the prevalence and characteristics of troponin elevation were examined in 244 patients with acute ischemic stroke but without overt ischemic heart disease. Troponin T (TnT) and creatine kinase-MB (CK-MB) concentrations were measured and 12-lead electrocardiograms obtained daily during the first 5 days of admission. Myocardial perfusion scintigraphy was performed in patients with TnT levels of 0.10 micro g/L and in comparable controls without elevation of TnT. Patients were followed for a mean of 19 +/- 7 months, with all-cause mortality as the clinical end point. Elevated levels of TnT (>0.03 micro g/L) and creatine kinase-MB (> or =10 micro g/L) were observed in 10% and 9% of patients, respectively. Patients with elevated TnT had higher frequencies of heart and/or renal failure. Perfusion abnormalities on myocardial perfusion scintigraphy at rest were not more frequent or pronounced in patients with TnT levels of > or =0.10 micro g/L than in the control group. Only 7 patients (3%) had elevations of TnT or creatine kinase-MB and electrocardiographic changes suggesting acute myocardial infarctions. According to univariate and multivariate analyses, elevation of TnT was significantly associated with mortality. In conclusion, elevated levels of TnT are rare in patients presenting with ischemic stroke but without overt ischemic heart disease. Heart and renal failure rather than myocardial infarction are the most likely causes. When present, elevation of TnT seems to be useful in identifying patients who are at increased risk of dying within the following 2 years.

Aged↗
PubMed2006

Using the Platelet Function Analyzer-100 for monitoring aspirin therapy.

INTRODUCTION: The aim of the study was to evaluate the test characteristics of the Platelet Function Analyzer-100 (PFA-100) in patients treated with aspirin. METHODS AND RESULTS: The study consisted of two sub-studies. In study 1, 10 patients with ischemic heart disease (IHD) and 10 controls had platelet function assessed by optical platelet aggregation and the PFA-100 method in two 5-week periods. Patients with IHD were treated with aspirin 150 mg/day (first 5-week period), and 300 mg/day (second 5-week period), whereas the controls only received aspirin (150 mg/day) during the second 5-week period. From the results of study 1, we found that a cut-off value for the PFA-100 collagen/epinephrine cartridge <165 s identified patients not taking aspirin (sensitivity 0.91, specificity 1.00). A good agreement between the PFA-100 method and optical platelet aggregation was found. Within-subject variation for the PFA-100 collagen/epinephrine cartridge was +/-28%, as compared to +/-17% for the optical platelet aggregation. Study 2 included 298 aspirin treated patients who were admitted with symptoms suggestive of an acute myocardial infarction. Platelet function was assessed in duplicate by the PFA-100 collagen/epinephrine cartridge, and a 95% Limit of Agreement interval at [-65%, 65%] indicated a limited precision. CONCLUSION: We defined a cut-off value below which patients not taking aspirin can be identified. However, due to imprecision of the PFA-100 method repeated duplicate assessment of the collagen/epinephrine Closure Time is recommended.

Aged↗
PubMed2006

[Coronary angioplasty and coronary artery bypass surgery in older patients. Incidence, complications and mortality, 1999-2003].

INTRODUCTION: Persons over 70 years of age are the fastest-growing segment of the population. A major proportion of these elderly have ischemic heart disease and may need treatment. We describe the development of mechanical coronary revascularization in patients aged 70-79 years versus those 80 years of age or older over a five-year period. MATERIALS AND METHODS: During 1999, 2001 and 2003, a total of 774 patients over 70 years of age had coronary angioplasty (PCI) or coronary artery bypass surgery (CABG) performed at Odense University Hospital. The patients were separated according to type of intervention and age: 70-79 versus > or = 80 years of age. Retrospectively, descriptive characteristics, complication rates and six-month mortality rates were compiled. RESULTS: During the study period, the number of interventions increased from 182 to 374 per year. In the patients > or = 80 years of age, a tenfold increase in the number of procedures was noted, whereas the frequency in the younger patients was approximately doubled. During the five-year period, the proportion of CABGs performed was stable, but the frequency of PCIs increased by a factor of five. Over time, the number of acute interventions increased. Patients > or = 80 years of age more frequently had complications than did patients 70-79 years of age. The six-month mortality rate increased throughout the study period and was highest in patients > or = 80 years of age. CONCLUSION: During the five-year period from 1999 to 2003, the total number of coronary revascularizations in the elderly increased. The main reason for this was a marked increment in the use of PCIs and a general increase in the use of revascularizations in patients 80 years of age or older. PCI in the elderly is associated with a lower frequency of complications.

Aged↗
PubMed2006

[Bleeding complications after treatment with clopidogrel and acetylsalicylic acid after acute coronary syndrome].

INTRODUCTION: The Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) study showed that patients with unstable angina pectoris (UAP) and non-ST-elevation myocardial infarction (NSTEMI) benefit from combined therapy with acetylsalicylic acid (ASA) and clopidogrel. However, only patients entering clinical randomized trials were studied. We sought to assess whether the risk of bleeding increased after the introduction of the CURE criteria in an unselected population of Danish patients with NSTEMI or UAP. MATERIALS AND METHODS: The CURE criteria were implemented in the Department of Cardiology, Odense University Hospital, in December 2001. Two consecutive one-year periods were studied: period 1, December 2000-November 2001, and period 2, December 2001-November 2002. Patient charts were reviewed, and major bleeding complications and the primary clinical end point (non-fatal myocardial infarction, stroke or death) was registered. Follow-up took place one year later. RESULTS: In all, 290 patients were included in period 1 and 189 in period 2. During period 1, there were 12 (4.1%) and during period 2, 21 (11.1%) major bleeding events (odds ratio 3.07; 95% CI 1.42-6.65; p = 0.005). Compared with the patients treated with clopidogrel and ASA in the CURE study, we also found a three times greater risk of major bleeding in period 2. In particular, patients over 70 years of age and patients undergoing bypass surgery were at heightened risk. The incidence of the primary clinical end point was higher in both period 1 and period 2 than in the CURE study. CONCLUSION: Our study demonstrates an increased risk of major bleeding in unselected patients receiving combination therapy with ASA and clopidogrel after UAP or NSTEMI. Major bleeding complications most frequently occur in patients above 70 years of age and following bypass surgery.

Age Factors↗
PubMed2006

Prevalence of aspirin resistance in patients with an evolving acute myocardial infarction.

OBJECTIVE: To study the prevalence and importance of aspirin resistance in patients with an evolving acute myocardial infarction (AMI) by use of the Platelet Function Analyzer-100. INTRODUCTION: Previous studies have demonstrated the existence of aspirin resistance, but the clinical relevance of the phenomenon remains to be clarified. If aspirin resistant patients comprise a high-risk subgroup, it might be expected that the prevalence of aspirin resistance in patients with AMI would be higher than in patients without AMI. We hypothesized that the prevalence of aspirin resistance in patients with AMI was twice the prevalence in patients without AMI. METHODS: We included 298 consecutive patients with known cardiovascular disease who were admitted to hospital with symptoms suggestive of an AMI. All had been taking aspirin 150 mg/day for at least 7 days prior to hospital admission. Platelet function was measured immediately at admission, and aspirin resistance was defined as a collagen/epinephrine Closure Time (CT(CEPI))<165 s. RESULTS: We found that 70 (23.5%) patients were aspirin resistant, and 70 (23.5%) patients ended up with the diagnosis of an AMI. The prevalence of aspirin resistance was significantly higher in patients with AMI as compared to patients without (36% versus 20%, OR 2.26, CI 95% 1.19-4.22, p=0.0058). The CT(CEPI) measured at admission was an independent factor associated with an AMI. CONCLUSIONS: Aspirin resistance is present in almost one fourth of patients admitted to hospital with symptoms suggestive of an AMI, and aspirin resistance is significantly associated with the diagnosis of a definite AMI.

Aged↗
PubMed2006

Redefinition of the Q wave -- is there a clinical problem?

This study evaluated the potential consequences of the redefined joint European/American electrocardiographic criteria for an established myocardial infarction (MI). New and previous diagnostic Q-wave criteria were used in patients with stable angina pectoris. Seventy-nine patients with and 77 patients without a documented previous MI were compared using the results of myocardial perfusion imaging at rest as a reference. With the new Q-wave criteria, 71% of the former group and 40% of the latter had evidence of established MI compared with 33% and 3% when using the previous criteria (p <0.0001). Sensitivity, specificity, and positive and negative predictive values were 71%, 60%, 64%, and 67% for the new criteria versus 33%, 97%, 93%, and 59% with the previous criteria. These data suggest that that the new Q-wave criteria may be too nonspecific, resulting in an inappropriately high number of false-positive results.

Adult↗
PubMed2005

A critical appraisal of the phenomenon of aspirin resistance.

Aspirin is the mainstay antiplatelet treatment in patients with high risk of cardiovascular atherothrombotic events, and its beneficial effect is documented in several clinical trials. Nevertheless, the effectiveness of aspirin has been questioned by the emergence of the concept of 'aspirin resistance' (AR). This phenomenon, although lacking a precise definition, covers the fact that some patients do not exhibit the expected platelet inhibition by use of various techniques for measuring platelet function. In this critical review, we evaluate the methods used for measuring AR. We will discuss the available data regarding the prevalence and the clinical importance of the phenomenon. Finally, the potential mechanisms underlying AR are considered.

Aspirin↗
PubMed2005

Existence of a clinically relevant interaction between clopidogrel and HMG-CoA reductase inhibitors? Re-evaluating the evidence.

Clopidogrel is an inactive prodrug, which requires activation by the cytochrome P450 3A4 system in order to exert its antiplatelet action. Some statins (atorvastatin, lovastatin and simvastatin) also requires metabolism by the cytochrome P450 3A4 system. From a theoretical point of view, a clinical relevant interaction may exist between clopidogrel and cytochrome P450 3A4 metabolized statins. Nine studies have investigated the existence of this potential interaction. Seven studies have used results based on platelet function as surrogate endpoints and two studies have dealt with objective clinical events including mortality, acute myocardial infarction and stroke. However the studies have yielded conflicting results. This controversy is primarily caused by substantial differences in study design and methods used for assessment of the antiaggregatory effect of clopidogrel. Most studies have included too few patients, and there appears to be no consensus regarding the definition of and optimal way of measuring the platelet inhibitory effect of clopidogrel. Therefore an adequately powered prospective study, ensuring elimination of identified possible confounders and with the use of a well-defined surrogate ex vivo parameter should be performed.

Atorvastatin↗
PubMed2005

The antiplatelet effect of clopidogrel is not attenuated by statin treatment in stable patients with ischemic heart disease.

Recent studies suggest that cytochrome P450 (CYP) 3A4 metabolized statins attenuate the antiaggregatory effect of clopidogrel. We evaluated how CYP3A4 metabolized statins and non-CYP3A4 metabolized statins influence platelet aggregation when given concomitantly with clopidogrel. Sixty-six stable patients with ischemic heart disease were included in this parallel group study. All patients were on clopidogrel and aspirin. Thirty-three patients received a CYP3A4 metabolized statin (simvastatin or atorvastatin), and 33 were treated with a non-CYP3A4 metabolized statin (pravastatin). The antiplatelet effect of clopidogrel was assessed at inclusion and 21 days after statin discontinuation. Platelet function was evaluated by two methods 1) optical platelet aggregometry after stimulation with 20 and 30 microM ADP, and 2 and 4 mg/l collagen, respectively, 2) a Platelet FunctionAnalyzer-100. The primary effect measure was final platelet aggregation after stimulation with 20 microM ADP. No difference was observed between patients treated with a CYP3A4 metabolized statin and patients receiving a non-CYP3A4 metabolized statin (30% point (7-42) versus 20% point (9-32), p = 0.83). Platelet aggregation was not improved by discontinuation of statins for 21 days. Indeed, we found that statin treatment given concomitantly with clopidogrel resulted in an improved platelet inhibition when compared to clopidogrel given alone. The antiplatelet effect of clopidogrel is not attenuated by concomitant treatment with a CYP3A4 metabolized statin in patients with clinical stable ischemic heart disease.

Aged↗
PubMed2003

[The importance of physical exercise in rehabilitation of patients with ischemic heart disease].

The present overview is based on recent meta-analyses of randomised clinical studies on rehabilitation programmes for patients with ischaemic heart disease. It can be concluded that only programmes in which exercise either had been the main intervention or an essential part of a comprehensive programme significantly reduced both total and cardiac mortality by approx. 25-30%.

Coronary Disease↗