Search PubMed⌕ Search

Biomedical subjects

H Kreuzer

Publications and source records attributed to H Kreuzer.

At least 19 recordsLinked to original sources

[Experiences with temporary vena cava filters in 114 at-risk patients with thrombosis or thromboembolism].

BACKGROUND AND OBJECTIVES: The indications for temporary implantation of a vena cava filter remain unclear and there are as yet few data about its complications and reliability. It was the aim of this study to determine the efficacy and complication rate of the temporary use of a vena cava filter (VCF) in a large group of patients at high risk of pulmonary embolism, and thus contribute to defining the indications for such temporary implantation. PATIENTS AND METHODS: Between November 1991 and October 1997 a total of 118 VCF were implanted in four groups of a total of 114 patients (67 women, 47 men; average age 45.3 +/- 19.8 [12-82] years) to prevent pulmonary embolism: those (1) with massive or fulminant pulmonary embolism (n = 54); (2) with mechanical thrombus fragmentation and (or) local catheter-delivered systemic thrombolysis in pelvic, leg or caval vein thrombosis (n = 42); (3) with systemic thrombolysis in case of floating thrombi at the femoral, iliac or caval veins (n = 7); and (4) as perioperative measure in caesarean section, venous thrombectomy, other surgical interventions or when anticoagulation had to be discontinued in patients with deep vein thrombosis (n = 11). RESULTS: Filters remained implanted for a mean of 6.1 +/- 3.4 (1-16) days. Placement had to be corrected because of filter dislocation in eight patients. Proven pulmonary embolism occurred after filter implantation in only one patient, after filter displacement into the unthrombosed contralateral iliac vein. Thrombus deposition on the filter before its removal was demonstrated in nine patients: thrombolysis was effective in seven of them, while thrombosed filters had to be removed surgically in two. Residual thrombi were found on the filter in six further patients. No pulmonary embolism occurred in connection with filter removal. Local complications at or around the site of insertion of the introducing catheter occurred in 53 of the 114 patients (46.5%): haematoma in 42, infection in 21 and brachial vein thrombosis in three patients. CONCLUSIONS: The rate of clinically relevant pulmonary embolism can probably be reduced to a minimum by the implantation of a temporary vena cava filter. The overall complication rate is high, but serious complications are rare.

Adolescent↗

Hypercoagulability in a patient with hypodysfibrinogenemia: implications for clinical management.

Dysfibrinogenemia accounts for approximately 0.7% of thrombophilia in patients with venous thromboembolic disease. In 20% of these patients, plasma thrombophilic dysfibrinogen is below 1.0 mg/ml, defining hypodysfibrinogenemia. We describe a young female patient, in whom hypodysfibrinogenemia was the cause of several severe thromboembolic events which occurred even under oral anticoagulation monitored by a standard prothrombin time (PT) test. In this patient, the standard PT test according to Quick underestimated the plasma coagulability in vivo, presumably due to the low levels of dysfunctional fibrinogen as the substrate of the thromboplastin reagent. A PT test supplemented with bovine plasma fibrinogen (Thrombotest) revealed lower fibrinogen-independent international normalized ratio (INR) values in the proposita on oral anticoagulation compared to a control group with eufibrinogenemia. Monitoring therapy with the fibrinogen-independent Thrombotest secured safe anticoagulation in this patient. We suggest to consider PT tests with exogenous fibrinogen (e.g. Thrombotest) to monitor oral anticoagulation in the rare thrombophilic patients with hypodysfibrinogenemia.

Adult↗

[Practicability and clinical relevance of routine psychological screening of patients in general internal medicine units].

In medical patients, anxiety and depression are frequent but often undiagnosed problems. The aim of the present study was to test and evaluate a psychological screening in medical in-patients. Using the Hospital Anxiety and Depression Scale (HADS), we screened 454 out of 743 consecutive medical in-patients. Physical symptoms and diagnoses were also recorded. Elevated scores for anxiety and depression were found in 20.8% and 23.9%, respectively. They were relatively independent of physical findings but correlated with subjective symptoms. In a subgroup who completed the questionnaire twice, HADS scores remained constant until discharge. Cardiological patients with abnormal baseline anxiety stayed significantly longer in hospital than those who were not anxious. Over a one-year follow-up, initially depressed patients had a risk of in-hospital death that was 2.5 times higher. This effect remained stable after controlling for baseline diagnoses and indices of severity of the disease.

Adult↗

[The renin-angiotensin system in cardiovascular diseases].

BACKGROUND: The renin-angiotensin system is mainly involved in several cardiovascular diseases and in the pathophysiology of heart failure. It exists as a circulating and a local system which can be differently regulated. Interventions in this system by angiotensin-converting enzyme (ACE) antagonists or angiotensin-receptor antagonists slow the progression of heart failure and result in prolongation of life expectancy and improvement of hemodynamics. MECHANISMS OF ACTION: The main underlying mechanisms are: 1. Heart failure results in activation of the renin-angiotensin system as a compensatory mechanism with elevation of circulating angiotensin II, norepinephrine and vasopressin. Antagonists of this compensatory mechanisms acutely result in improvement of the hemodynamic situation. 2. Elevated circulating and local renin-angiotensin systems cause chronic structural myocardial and vascular effects. Angiotensin-converting enzyme antagonists and angiotensin-receptor blockers modulate and partly antagonize these structural changes such as myocardial hypertrophy, myocardial fibrosis and vascular proliferative responses. Gene and receptor regulation of the system are currently not fully understood and are subject of intensive research. 3. The renin-angiotensin system is closely related to the bradykinin system and thus indirectly to nitric oxide and endothelial function. Bradykinin has multiple other effects on the hemostatic system as a well as on the myocardium and vascular system. CONCLUSION: These complex interactions require further evaluation. Research with specific bradykinin antagonists will give new insights into this system.

Angiotensin-Converting Enzyme Inhibitors↗

[Age related decrease of high density lipoproteins (HDL) in women after menopause. Quantification of HDL with genetically determined HDL arylesterase in women with healthy coronary vessels and in women with angiographically verified coronary heart disease].

BACKGROUND: The decline in the concentration of high density lipoproteins (HDL) observed in postmenopausal women is thought to contribute to the increasing incidence of coronary artery disease (CAD) after menopause. Human serum arylesterase (EC 3.1.1.2) is exclusively associated with HDL. We therefore investigated possible differences in the decline of HDL-levels and of HDL-subfractions HDL2 and HDL3 between postmenopausal women without and with angiographically documented CAD. PATIENTS AND METHODS: HDL-, HDL2-and-HDL3- concentrations were studied in postmenopausal women with angiographically documented CAD (n = 24; 51 to 72 years mean: 62 years) and compared to HDL-parameters of women without CAD (n = 22; 51 to 81 years, mean: 58 years). Arylesterase activities of HDL2-and HDL3-subfractions and HDL2-cholesterol concentrations were determined after differential precipitation with polyethylene glycol (4.7 mM PEG). Phenotyping of HDL-arylesterase was achieved in CAD patients and in women without CAD after determining hydrolysis of arylesterase substrates paraoxon (PO) and phenylacetate (PA) by calculating paraoxonase/arylesterase activity ratios R (R = [PO]/[PA] x 1000): phenotype A (n = 26) with R < 2.5, phenotype AB (n = 16) with 5.0 < R < 10.7, and phenotype B (n = 4) with R > 13.5. RESULTS: In postmenopausal women with documented CAD, as compared to women without CAD, HDL-cholesterol (55 +/- 3 mg/dl vs. 69 +/- 3 mg/dl HDL2-arylesterase (25 +/- 1 kU/l vs. 33 +/- 2 kU/l), and HDL3-arylesterase (89 +/- 4 kU/l vs. 106 +/- 5 kU/I) were found to be significantly reduced. Analysis of the correlation of lipid parameters and age revealed in CAD patients, but not in postmenopausal women without CAD, a significant increase of total cholesterol (r = 0.42), and significant reductions of both HDL2-arylesterase (r = -0.47) and HDL3-arylesterase (r = 0.74) with increasing age. In contrast, HDL-cholesterol (r = -0.14) and HDL2-cholesterol (r = -0.06) of CAD patients showed only slight and non-significant reductions with age. Since HDL3-arylesterase was found to be age-dependently reduced in women without CAD (r = 0.17), HDL2-arylesterase of postmenopausal women, among all lipid parameters showed the most pronounced differences between women without CAD and CAD patients. The age-dependent decrease of HDL2-arylesterase in postmenopausal women with CAD does not result from an increased frequency of B-allele carriers in the subgroup of CAD patients with an age above the median (64 years). CONCLUSION: Genetically determined serum HDL-arylesterase is well suited to quantify HDL in postmenopausal women without and with CAD. HDL2-arylesterase of postmenopausal women should be evaluated as a screening parameter for both primary and secondary CAD prevention.

Aged↗

Monocyte activation in congestive heart failure due to coronary artery disease and idiopathic dilated cardiomyopathy.

OBJECTIVE: To investigate plasma tumor necrosis factor (TNF)alpha, tumor necrosis factor alpha soluble receptor I, interleukin-1beta and neopterin concentrations as markers of monocyte activation in patients with heart failure. STUDY DESIGN: The group consisted of patients with heart failure due to dilated cardiomyopathy (n=19) and coronary artery disease (n=11). Patients without cardiac failure served as controls (n=10). RESULTS: TNFalpha concentrations were elevated only in heart failure patients with coronary artery disease (2.9+/-0.3 pg/ml versus 1.7+/-0.3 pg/ml; P<0.05). When the patients were grouped according to acute and chronic failure, TNFalpha concentrations were significantly elevated in acute failure (3.1+/-0.4 pg/ml, n=6 versus 1.7+/-0.2 pg/ml, n=8; P<0.05). TNFalpha concentrations were elevated in patients with coronary artery disease and chronic heart failure compared to coronary artery disease patients without failure (2.0+/-0.4 pg/ml, n=6 versus 1.8+/-0.3 pg/ml, n=7; P<0.05). A higher proportion of patients with myocardial insufficiency showed increased lipopolysaccharide-inducible TNFalpha concentrations (10/30 versus 0/9, P<0.05). CONCLUSIONS: TNFalpha is elevated in patients with acute cardiac decompensation. Among patients with chronic heart failure only those with coronary artery disease exhibit increased levels. Cytokine concentrations are similar in heart failure due to dilated cardiomyopathy and coronary artery disease. Monocytes of patients suffering from cardiac insufficiency show an increased sensitivity towards stimuli such as lipopolysaccharides.

Biomarkers↗

Simultaneous manifestation of acute myocardial infarction and nephrotic syndrome.

This report describes the simultaneous manifestation of ischemic heart disease and nephrotic syndrome in a 37-year-old woman presenting with acute anterior myocardial infarction. Symptoms of nephrotic syndrome, such as facial and peripheral edema accompanied by proteinuria and hyperlipidemia, and onset of severe retrosternal pain developed within 24 h. Coronary angiography revealed a complete thrombotic occlusion of the proximal portion of the left anterior descending artery with no evidence of arteriosclerotic lesions. Histologic examination of renal biopsy, including electron microscopy, revealed evidence of minimal change glomerulonephritis. Ultrastructural studies demonstrated widespread effacement of epithelial foot processes. Elevated levels of circulating fibrinogen appeared to be an important factor for the hypercoagulable state in this patient, suggesting a causative relationship between coronary thrombosis and nephrotic syndrome.

Adult↗

[Cheyne-Stokes respiration in patients with congestive heart failure].

Cheyne-Stokes respiration (CSR) during sleep is common in patients with severe congestive heart failure induces repetitive oxygen desaturation with arousals, and impairs sleep. This causes daytime symptoms and likely an increase in sympathetic activity. It has, therefore, been suggested that CSR is independently related to mortality. The major mechanisms behind CSR include reduced body stores of oxygen, a low apneic threshold for carbon dioxide, prolonged circulation time between the lung and the carotid body, and disturbance of respiratory control due to arousals. It is apparent that the main task in treating CSR is the therapy of congestive heart failure. Indeed, diuretics to treat pulmonary congestion as well as ACE-inhibitors reduce CSR. Recently, theophylline (an antagonist of the ventilatory depressant adenosine) was shown to reduce CSR and oxygen-desaturation. Continuous positive airway pressure did improve CSR but not sleep and may reduce cardiac output in a subgroup of patients with heart failure. Nocturnal oxygen reduces CSR and improves exercise tolerance as well as sleep. This and its apparent safety makes oxygen an appropriate treatment for nocturnal CSR. Whether successful treatment of nocturnal CSR has any impact on the natural course of heart failure needs to be determined in further studies.

Cheyne-Stokes Respiration↗

[Intracoronary ultrasound during recanalization of chronic coronary occlusions: Relation to restenosis and reocclusion after balloon angioplasty or stent implantation].

Chronic coronary occlusions carry a high recurrence rate, and coronary stenting evolves as a preferred therapy of these complex lesions. Insight into the morphology of the occluded segment by intracoronary ultrasound may provide information which may help to improve the interventional strategy and the long-term outcome. After successful recanalization of chronic coronary occlusions (4 weeks to 33 months; median 3.2 months) in 59 patients, 29 patients were treated by balloon angioplasty alone, and 30 patients received one or more coronary stents because of complicated dissections or a high-grade residual stenosis after balloon dilatation. Intracoronary ultrasound was used to assess the lesion morphology and to quantify the angioplasty result. The luminal area, the total vessel area and the extent of the plaque burden were measured proximal and distal to the occlusion and at the narrowest site within the occlusion or the coronary stents, and the elastic recoil was calculated. Plaques in chronic occlusions were predominantly hypodense, and 44% were characterized by a multilayered plaque appearance. The elastic recoil was higher in multilayered plaques than in other plaques (46 +/- 19% vs. 34 +/- 15%; p < 0.05). Based on the quantitative ultrasound measurement after the initial balloon dilatation, it appeared that the initial balloon was undersized in 54%. The lumen area in patients with balloon angioplasty alone was increased from 4.02 +/- 1.34 mm2 to 5.49 +/- 1.47 mm2 and in the stented patients from 3.58 +/- 1.04 mm2 to 7.10 +/- 1.92 mm2. The recurrence rate in patients with balloon angioplasty was 48% with 24% reocclusions. Patients with recurrence had a slightly lower lesion area (3.97 +/- 1.41 mm2 vs. 4.71 +/- 1.44 mm2; n.s.) and minimum diameter (1.82 +/- 0.31 mm vs. 2.14 +/- 0.40 mm; p < 0.05) after dilatation. In stented patients the recurrence rate was 27% with two early stent thrombosis (6.7%) and no late reocclusion. In patients with recurrence the achieved stent area was significantly smaller than in those without restenosis (5.71 +/- 0.90 mm2 vs. 7.59 +/- 1.96 mm2; p < 0.01), and the degree of vascular remodelling at the site of the occlusion was less pronounced. Intracoronary ultrasound showed sonographic plaque characteristics in chronic occlusions which responded poorly to balloon dilatation alone. Stent implantation improved considerably the luminal area gain and could reduce the long-term outcome. To further improve the recurrence rate in stents, an optimized stent expansion should be achieved, and intracoronary ultrasound could provide an ideal tool for this purpose.

Aged↗

Risk factors for acute and subacute stent thrombosis after high-pressure stent implantation: a study by intracoronary ultrasound.

BACKGROUND: In the era of coronary stenting with high-pressure expansion, stent thrombosis remains a major life-threatening risk. Because of its superior imaging mode, intracoronary ultrasound could provide insight into potential risk factors for stent thrombosis. PATIENTS AND METHODS: In 215 patients with stent implantations controlled by intracoronary ultrasound, four occurrences of subacute stent thrombosis, two complete acute thrombotic occlusions, and four occurrences of incomplete acute thrombosis were observed. All stents were expanded with inflation pressures of at least 14 atm ( 17+/-3 atm). The clinical data and the qualitative and quantitative ultrasound information were compared between stents with thrombosis and stents without thrombosis. The luminal area and the plaque border of the reference segments, and of the smallest and largest site of the stented segment after the initial and final expansion, were measured. RESULTS: Stents in the left anterior descending artery were more often involved in stent thrombosis than other vessels, but the vessel dimensions in this target vessel were smaller than in the right coronary artery. The plaque burden was considerably larger after stent implantation with subsequent thrombosis compared with no thrombosis (74.1+/-8.8% vs 63.6+/-8.0%; p < 0.001), and the stent area was smaller (4.80%+/-1.33 mm2 vs 6.86+/-2.08 mm2; p < 0.01 ). In stents with thrombosis the plaque burden of the stent site with the smallest and largest lumen differed by 15.2%, whereas the difference in plaque burden in stents without thrombosis was 2.7%. Intracoronary ultrasound showed that the best risk predictor of thrombosis was the residual plaque burden of the stented segment (odds ratio 15.7 [confidence interval 2.4 to 104.7]), and a small stent area after implantation (odds ratio 6.8 [confidence interval 1.9 to 24.3]). CONCLUSION: In a multivariate risk analysis plaque burden was the strongest independent risk factor for stent thrombosis. The amount of residual plaque mass around the stent might be a potential trigger for thrombus formation.

Acute Disease↗

Complete morphologic and functional resolution of endocarditis of a Toronto stentless porcine bioprosthesis: a study by serial transesophageal echocardiography.

Prosthetic valve endocarditis is a serious complication after valve replacement with an incidence of 0.8% for both mechanical and bioprosthetic valves. The new Toronto stentless porcine valve (SPV) for aortic replacement offers promising early results in hemodynamics and a low incidence of valve-related complications. The yearly incidence of bacterial endocarditis was reported to be 1% to 1.5%. Though complications such as a perivalvular abscess or anular dehiscence require immediate surgery, a conservative management of infective endocarditis may be possible in carefully selected cases. This is the case of a patient with late prosthetic valve endocarditis of a Toronto SPV bioprosthesis, who, in spite of large vegetations on all three valve cusps, responded well to conservative treatment. This response was monitored through repeated transesophageal echocardiographic studies (TEE), which documented complete functional recovery of the valve.

Aged↗

Nocturnal oxygen and hypercapnic ventilatory response in patients with congestive heart failure.

Patients with congestive heart failure and Cheyne-Stokes respiration have a low arterial oxygen saturation, especially during sleep, which can be increased by breathing oxygen. Chronic alterations in blood gases are known to modulate the hypercapnic ventilatory response (HCVR). We therefore evaluated whether the HCVR is influenced by nocturnal nasal oxygen in patients with heart failure and Cheyne-Stokes respiration. Twenty patients with chronic congestive heart failure and a left ventricular ejection fraction < or = 35% (mean 18.3% +/- SD 6.0%) as well as 25 healthy control subjects were studied. The patients were assigned to 1 week each of nocturnal nasal oxygen and room air with a flow of 41 min-1 in a randomized cross-over fashion. After each week resting ventilation and HCVR were evaluated by the rebreathing technique. Breathing oxygen during the night for 1 week increased the basal nocturnal oxygen saturation from 92.5% +/- 1.6% to 96.5% +/- 0.9% (P < 0.000,01) and reduced Cheyne-Stokes respiration. HCVR was 1.22 +/- 0.90 l min-1 mmHg-1 after nocturnal room air and did not differ from that in the control subjects (1.31 +/- 0.62 l min-1 mmHg-1). In the patients HCVR decreased to 0.91 +/- 0.52 l min-1 mmHg-1 after nocturnal oxygen (P = 0.019). There were no significant changes with nocturnal oxygen in resting minute ventilation, respiratory rate or end-tidal PCO2. We conclude that nocturnal nasal oxygen reduces HCVR in patients with congestive heart failure and Cheyne-Stokes respiration.

Carbon Dioxide↗

Complications of intra-aortic balloon counterpulsation. The role of catheter size and duration of support in a multivariate analysis of risk.

AIMS: The aim of this study was to assess the risk of intra-aortic balloon counterpulsation and to identify clinical and procedural variables that would predict complications. METHODS AND RESULTS: We analysed 381 consecutive patients who were treated between 1977 and 1995 at our catheterization laboratory and/or medical intensive care unit. The complications considered relevant were limb ischaemia requiring catheter removal, vascular injury, bleeding requiring transfusion, embolic events, and infection. In eight patients the balloon could not be inserted. The rate of complications for the remaining 373 patients was 12.9%. Between 1977 and 1980, surgical insertion was performed using a 12 French catheter with a complication rate of 30.4% (seven of 23 patients). Percutaneous implantation, performed after 1981, had an overall complication rate of 11.7% (41 of 350 patients). Using thinner catheters for percutaneous placement was associated with a reduction in the rate of complications, from 20.7% (17 of 82 patients) for 12 French catheters to 9.9% (10 of 101 patients) for 10.5 French catheters (P = 0.04), and 8.4% (14 of 167 patients) for 9.5 French catheters (P = 0.006). Multivariate logistic regression analysis identified duration of counterpulsation > 48 h (odds ratio 3.6), catheter size (odds ratio 3.4 for 12 French catheters), peripheral vascular disease (odds ratio 2.7), and shock (odds ratio 2.0) as independent risk factors for counterpulsation-associated complications. When considering 9.5 French catheters only (167 patients, all after 1992), the sole remaining independent risk factor was duration of counterpulsation > 48 h (odds ratio 3.8). Those patients with 9.5 French catheters in whom counterpulsation did not exceed 48 h had a low complication rate of 3.9%. CONCLUSION: The rate of percutaneous intra-aortic balloon counterpulsation complications was thus significantly reduced by employing thinner catheters. It was at an acceptable level for 9.5 French catheters, where a long duration of counterpulsation emerged as the most significant factor associated with complications. Whether using even thinner catheters in combination with a sheathless implantation technique further minimizes the risk of counterpulsation remains to be seen.

Aged↗

Cardiac involvement in proximal myotonic myopathy.

Proximal myotonic myopathy (PROMM) is a recently described autosomal dominantly inherited disorder resulting in proximal muscles weakness, myotonia, and cataracts. A few patients with cardiac involvement (sinus bradycardia, supraventricular bigeminy, conduction abnormalities) have been reported. The cases of three relatives with PROMM (weakness of neck flexors and proximal extremity muscles, calf hypertrophy, myotonia, cataracts) are reported: a 54 year old man, his 73 year old mother, and 66 year old aunt. All three presented with conduction abnormalities and one had repeated, life threatening, sustained monomorphic ventricular tachycardia. This illustrates that severe cardiac involvement may occur in PROMM.

Aged↗

Coxsackievirus genome in myocardium of patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy.

Enteroviruses are known as major infectious agents for inflammatory heart diseases such as myocarditis and dilated cardiomyopathy (DCM). Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) is characterized by replacement of right ventricular myocardium by fatty and fibrous tissue. In about 65% of patients inflammatory infiltrates suggest an inflammatory or infectious etiopathogenesis. To test this hypothesis, we investigated endomyocardial biopsies of patients with ARVC, with myocarditis or DCM, and from patients with non-inflammatory cardiac disorders for the presence of enteroviral genome. Enteroviral RNA with homology to coxsackieviruses type B was detected in 3 of 8 patients with ARVC (37.5%), in 7 of 23 patients with myocarditis or DCM (30.4%), but in none of 5 patient with non-infectious myocardial diseases (p < 0.05 compared to ARVC patients). These results support earlier suggestions that coxsackievirus infection of the myocardium is possibly related to the pathogenesis of ARVC.

Adult↗

Superiority of combined CK-MB and troponin I measurements for the early risk stratification of unselected patients presenting with acute chest pain.

BACKGROUND: Recent studies have suggested that positive troponin I tests are associated with an increased risk of cardiac death during short-term follow-up. However, it is unknown if troponin I tests alone or in addition to CK-MB measurements are superior to predict unfavorable outcome during long-term follow-up. PATIENTS AND METHODS: In a prospective, double-blind study we assessed the prevalence and prognostic value of combined troponin I and CK-MB tests in an unselected cohort of patients (n = 292) admitted to the emergency department for acute chest discomfort. Patients were grouped according to the diagnosis on discharge in those with acute myocardial infarction (1), unstable angina (2), and noncardiac chest pain (3). Six months after enrollment, death rates were obtained and follow-up interviews were performed with respect to survival, recurrence of chest pain, and myocardial infarction. RESULTS: In patients with evidence of coronary heart disease, the mortality rate for abnormal troponin I and normal CK-MB levels was 5.0%. Baseline troponin I and elevated CK-MB levels were associated with a mortality rate of 4.0%. However, the mortality rate was significantly higher (11.1%) in patients presenting with elevated troponin I and CK-MB values. In patients without myocardial infarction on admission, 10.5% with positive troponin I tests died compared to 1.6% with negative tests. The mortality rate in patients without myocardial infarction was 2.7% for patients with elevated CK-MB but normal troponin I values. In patients with both markers elevated a significantly higher mortality rate (16.7%) was found, representing a 6-fold increase in the death event rate. With the additional knowledge of troponin I values, it could be demonstrated that certain cases were misclassified as having noncardiac chest pain. At least some of the latter patients with above-normal values of troponin I were retrospectively to be reclassified as unstable angina. Acute non-Q-wave myocardial infarctions were occasionally misdiagnosed as either angina pectoris or nonischemic chest pain. CONCLUSIONS: Our data suggest the superiority of combined CK-MB and troponin I measurements in clinical practice for the early risk stratification of patients presenting with acute chest pain. In nonmyocardial infarctions, both CK-MB and troponin I convey independent prognostic information with regard to fatal outcome. Troponin I tests in addition to CK-MB measurements contribute to a lower rate of misdiagnoses.

Aged↗

Single-laser approach for fluorescence guidance of excimer laser angioplasty at 308 nm: evaluation in vitro and during coronary angioplasty.

BACKGROUND AND OBJECTIVE: Spectroscopic guidance of laser angioplasty has been attempted using a diagnostic He-Cd laser in addition to the therapeutic laser system. This study evaluated a single-laser approach for simultaneous ablation and fluorescence excitation. STUDY DESIGN/MATERIALS AND METHODS: A spectroscopy system was coupled to a clinical XeCl excimer laser. Ablation of 162 human aortic samples in saline and blood with 45 mJ/mm2 per pulse yielded 676 fluorescence spectra validated histologically. The same equipment was used in 16 patients for angioplasty of 18 coronary stenoses applying 500 to 1,725 pulses with 45 to 60 mJ/mm2 under saline flushing. A total of 783 spectra were recorded and validated by intracoronary ultrasound (categories: atheroma, fibrous plaque, calcified lesion). RESULTS: In vitro, 5 types of spectra could be differentiated: (1) atheroma, (2) fibrous plaque, (3) calcified lesion in saline, (4) media, and (5) calcified lesion in blood. Discriminant analysis prospectively classified 576 validation spectra with the following sensitivity and specificity for each type: (1) 83.5 and 97.1%, (2) 85.7 and 96.8% (3) 100 and 98.5%, (4) 98.1 and 99.3%, (5) 98.9 and 100%, respectively. In vivo type 1, 2, 3, and 5 spectra were also observed, but not the media spectrum. The predominant sonographic category also prevailed in spectroscopy. Calcified lesions yielded type 3 and 5 as well as mixed spectra. CONCLUSIONS: Using an excimer laser for angioplasty allows combining ablation and fluorescence excitation without a diagnostic laser. Principal types of atherosclerotic lesions and the media can be differentiated spectroscopically with this approach.

Adult↗

Vessel reconstruction in total coronary occlusions with a long subintimal wire pathway: use of multiple stents under guidance of intravascular ultrasound.

A frequent cause of failure of the recanalization of a total coronary occlusion is a subintimal pathway of the guide wire. Three cases of occluded right coronary arteries are presented in which a distal reentry into the true vessel lumen was achieved. Intravascular ultrasound was used to locate the exit and reentry of the guide wire, and to plan the position of multiple stents for the coverage of this subintimal pathway. In all cases antegrade flow to the distal coronary bed was restored.

Adult↗