bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of long‐term transdermal nitrate treatment on left ventricular function in patients following myocardial infarction
Authors: Kiraly Csaba , Kiss Attila , Timar Sandor , Kristof Eva , Hegedus Ida , Edes Istvan 
Published: June 2007

AbstractBackground: Nitrates are widely used for the treatment of myocardial infarction (MI). The large megatrials (GISSI‐3 and ISIS‐4) did not in fact demonstrate a significant decrease in mortality in the nitrate‐treated group. However, examination of the number of postinfarction angina episodes and the occurrence of cardiogenic shock in the GISSI‐3 study did reveal significant decreases.Hypothesis: It was hypothesized that chronic nitrate treatment after an MI preserves left ventricular systolic and/or diastolic functions.Methods: Patients were divided into two groups: those receiving chronic nitrate treatment for 6 months after an MI (n = 30), and those without such treatment (n = 29). Echocardiography was performed 3, 14, 42, and 180 days after the infarction. The changes in early diastolic and atrial contraction‐related mitral valve inflow pattern and deceleration time were assayed. Alterations in systolic, diastolic, and atrial reverse flow velocities in the pulmonary vein were measured, as were ejection fraction (EF), the number of registered angina episodes, and the maximal ST‐segment depression in response to the stress test.Results: During the 6‐month study period, the increase in systolic pulmonary venous flow velocity was significantly larger in the nitrate group than in the controls. The decreases in the velocities of the diastolic and the atrial reverse flow were also more pronounced in the nitrate group than in the controls. The EF was improved only in the nitrate group. Examination of the maximal ST‐segment depression in response to the stress test revealed a significant decrease in the nitrate group only. There were no significant differences between the two groups in the number of registered angina episodes or mitral inflow pattern.Conclusions: The study showed that prolonged nitrate treatment after an MI may help preserve diastolic left ventricular function.
Fibrin D‐dimer: A marker of psychosocial distress and its implications for research in stress‐related coronary artery disease
Authors: Von Känel Roland , Dimsdale Joel E. 
Published: June 2007

AbstractPsychosocial factors might mediate their adverse impact on coronary arteries by eliciting a hypercoagulable state via changes in sympathetic nervous system activity. A recent meta‐analysis of prospective studies reported an association of the hypercoagulability marker D‐dimer with an increased risk for coronary events. This review provides evidence that an elevated plasma D‐dimer level is a suitable marker for acute and chronic psychosocial distress. Prospective studies need to show whether stress‐related changes in D‐dimer may help explain the increased coronary risk with psychosocial distress.
Prospective comparison of coronary artery remodeling between acute coronary syndrome and stable angina in single‐vessel disease: Correlation between C‐reactive protein and extent of arterial remodeling
Authors: Hong Myeong‐Ki , Park Seong‐Wook , Lee Cheol Whan , Kim Young‐Hak , Kim June‐Hong , Song Jong‐Min , Kang Duk‐Hyun , Song Jae‐Kwan , Kim Jae‐Joong , Park Seung‐Jung 
Published: June 2007

AbstractBackground: Retrospective intravascular ultrasound (IVUS) studies showed that positive remodeling of coronary artery was associated with unstable clinical presentation. However, no prospective IVUS study has been performed to demonstrate such relationship. The relationship between C‐reactive protein (CRP) and coronary artery remodeling is unknown.Hypothesis: Positive remodeling might be related with acute coronary syndrome in the prospective IVUS study. C‐reactive protein levels might be associated with coronary artery remodeling.Methods: Preintervention IVUS images were prospectively obtained in 93 patients with single‐vessel disease (30 for acute coronary syndrome and 63 for stable angina). Serum sample for CRP measurement was collected 24 h prior to coronary intervention. The remodeling index was defined as a ratio of (lesion/average reference) external elastic membrane area. Positive remodeling was defined as a remodeling index > 1.05 and negative remodeling as a remodeling index < 0.95.Results: The remodeling index was 0.99 ± 0.13 in acute coronary syndrome versus 0.95 ± 0.12 in stable angina (p = 0.048). Positive remodeling was associated with acute coronary syndrome (43 vs. 19%), whereas negative remodeling was more frequent in stable angina (49 vs. 33%) (p = 0.047). C‐reactive protein levels were significantly higher in acute coronary syndrome than in stable angina (1.4 ± 2.0 vs. 0.5 ± 0.6 mg/dl, respectively, p = 0.002). However, there was no significant correlation between CRP levels and remodeling index (r = 0.078, p = 0.475).Conclusions: Positive remodeling may be related with acute coronary syndrome in the prospective IVUS analysis. C‐reactive protein levels may not predict the extent of arterial remodeling.
Predictive value of heart rate variability for the recurrence of chronic atrial fibrillation after electrical cardioversion
Authors: Akyürek ÖMer , Diker Erdem , Güldal Muharrem , Oral Derviş 
Published: June 2007

AbstractBackground: The relation between heart rate variability (HRV) and occurrence of atrial fibrillation (AF) in paroxysmal AF has been well studied, but there are controversial observations regarding the relation of HRV parameters to the recurrence of chronic AF after cardioversion.Hypothesis: The present study compared HRV parameters of patients with chronic AF on the second day of cardioversion with a healthy control group and investigated their predictive value for AF recurrence.Methods: Forty‐one patients with chronic AF (> 3 months), who had various underlying cardiovascular disorders, were enrolled to the study. Of these, 31 patients were successfully cardioverted by external direct current shock, but 27 patients fulfilled the entry criteria. Twenty healthy subjects served as a control group. On the second day of restoration of sinus rhythm, 24‐h Holter recording was obtained and the following time‐domain indices of HRV were measured: SDNN (the standard deviation of the mean RR interval expressed in ms), SDANN (the SD of the averages of RR intervals in all 5‐min segments of the 24‐h recording), rMSSD (the root mean square of differences of successive RR intervals), and pNN50 (the percentage of adjacent RR intervals that differed by more than 50 ms). Patients were followed‐up for 6 weeks for recurrence of AF.Results: After cardioversion, SDNN and SDANN were found to be significantly lower in the AF group than in the control group (86.4 ± 31.7 ms vs. 142.1 ± 40.2 ms, and 57 ± 17.4 ms vs. 124.4 ± 37.7 ms, p < 0.001 and p < 0.001, respectively). The indices of vagal modulation of heart rate (rMSS and pNN50) were not different between the AF group and the control group. Recurrence of AF was observed in 15 patients. In these patients, all HRV parameters were significantly depressed compared with those with maintained sinus rhythm. Logistic regression analysis revealed that only decreased pNN50 was an independent predictor of AF relapse (relative risk = 1.5, p = 0.02, 95% confidence interval 1.1‐2.2). There was also a trend toward a shortened SDNN as a predictor of AF recurrences.Conclusion: Suppressed HRV parameters and decreased vagal tone are probably a risk factor for AF recurrences after cardioversion to sinus rhythm in a specific subset of patients with chronic AF.
Significance of exercise‐induced ST changes in leads AVR, V5, and V1. Discrimination of patients with single‐ or multivessel coronary artery disease
Authors: Michaelides Andreas P. , Psomadaki Zoi D. , Aigyptiadou Maria‐Niki K. , Richter Dimitris J. , Andrikopoulos George K. , Dilaveris Polychronis E. , Tsioufis Konstantinos , Tousoulis Dimitris , Stefanadis Christodoulos I. , Toutouzas Pavlos K. 
Published: June 2007

AbstractBackground: It is known that exercise‐induced ST‐segment elevation in lead V1 (V1‐E) detects left anterior descending (LAD) stenosis. It was also postulated that ST elevation in aVR and simultaneous ST depression in V5 (aVR‐E + V5‐D) is a marker of ischemia due to significant stenosis of the LAD in patients with single‐vessel disease.Hypothesis: This study was undertaken to investigate the significance of the concomitant appearance of both electrocar‐diographic (ECG) ischemic markers, and of each of them alone during exercise, to detect either LAD stenosis as single‐vessel coronary artery disease (CAD), or multivessel CAD involving LAD stenosis.Methods: A total of 196 consecutive patients (152 men and 44 women, mean age 54 ± 7 years) with at least one of these ECG markers, who underwent treadmill exercise testing with the Bruce protocol and coronary arteriography, were studied.Results: Patients were divided into three groups. In Group A (83 patients with V1‐E + aVR‐E & V5‐D), 93% of patients with single‐vessel disease had significant LAD stenosis (p < 0.001), whereas 75% of patients with double‐vessel disease had significant stenoses of the LAD and the left circumflex (LCx) coronary arteries (p < 0.01). In Group B (97 patients with aVR‐E & V5‐D but without V1‐E), 43% of patients with single‐vessel disease had significant LAD stenosis (p < 0.08), whereas 85% of patients with double‐vessel disease had significant stenoses of the LAD and the right coronary artery (RCA) (p < 0.01). In Group C (16 patients with only V1‐E), 60% of patients with single‐vessel disease had significant LAD stenosis (p < 0.05), whereas 75% of patients with double‐vessel disease had significant LAD and LCx stenoses (p < 0.05).Conclusions: The concomitant appearance of exercise‐induced ST elevation in lead V1, ST elevation in lead aVR, and ST depression in lead V5, as well as the isolated appearance of ST elevation in lead V1 detect significant LAD stenosis as single‐vessel disease, or significant stenoses of LAD and LCx arteries in patients with double‐vessel disease, whereas the appearance of ST elevation in aVR & ST depression in V5 but without ST elevation in V1 correlates strongly with significant LAD and RCA stenoses and usually indicates double‐vessel disease.
Opportunities for improvement in the diagnosis and treatment of heart failure
Authors: McCullough Peter A. , Philbin Edward F. , Spertus John A. , Sandberg Keisha R. , Sullivan Roberta A. , Kaatz Scott 
Published: June 2007

AbstractBackground: Improved treatment of congestive heart failure (CHF) can slow disease progression, promote clinical stability, and prolong survival.Hypothesis: Patterns in diagnostic test utilization and pharmacotherapy among patients with newly diagnosed heart failure may affect outcomes.Methods: Claims data were analyzed from all diagnostic procedures and prescriptions from 1995 to 1998 in 3,353 patients with heart failure diagnosed within 1 year. Rates of diagnostic testing and categories of drugs prescribed were the main outcome measures. Demographic variables and type of provider were analyzed within a setting whose access to care was controlled.Results: Rates of diagnostic testing with respect to basic, metabolic/endocrine, alternative diagnoses, underlying ischemia, and left ventricular function varied as a function of gender, age, race, and primary versus specialty care provider. Only 4.7% of patients underwent all diagnostics and treatments recommended in current guidelines. However, those patients (27.5%) who underwent an evaluation for ischemic heart disease and were prescribed vasodilators or beta blockers enjoyed the lowest crude mortality.Conclusions: There are multiple opportunities apparent to improve the initial diagnostic and therapeutic care of patients with heart failure. There appears to be an early survival benefit with respect to use of vasodilators and beta blockers within the first year of treatment.
Isometric handgrip exercise during dobutamine‐atropine stress echocardiography increases heart rate acceleration and decreases study duration and dobutamine and atropine dosage
Authors: Yao Siu‐Sun , Moldenhauer Sonja , Sherrid Mark V. 
Published: June 2007

AbstractBackground: Dobutamine‐atropine stress echocardiography (DASE) is an established test for the diagnosis and risk stratification of patients with coronary artery disease. Atropine use to attain target heart rate prolongs test time.Hypothesis: The aim of this study was to assess the utility of isometric handgrip exercise (33% maximal voluntary contraction X 4 min) with DASE.Methods: We prospectively evaluated 131 patients undergoing DASE randomized to handgrip exercise or no handgrip. Effect of handgrip exercise on endpoints: time to target heart rate (85% maximum predicted), recovery time, total test time, mean dobutamine and atropine dosage, and the number of ischemic responses were assessed. Effect of current beta‐blocker medication use was also evaluated.Results: Heart rate rose more quickly in the handgrip group. At 6‐10 min (peak handgrip), mean heart rate rose 51 ± 14 beats/min in the handgrip group compared with 38 ± 18 beats/min in the no handgrip group (p < 0.0001). With handgrip, overall dobutamine study time was reduced by a mean of 4.3 min (16.4 ± 6.9 vs. 20.7 ± 8.4, p = 0.004) in all patients, and by a mean of 5.9 min in patients not on beta‐blocker medication (p = 0.001). The handgrip group also had a lower mean dose of dobutamine (25.8 ± 13.5 vs. 32.4 ± 16.4 mg, p = 0.025). The mean atropine dose was also lower (0.2 ± 0.4 vs. 0.4 ± 0.5 mg, p = 0.04). Handgrip exercise, however, did not decrease endpoints in patients on beta‐blocker medication.Conclusions: Use of isometric handgrip exercise with DASE decreases time to target heart rate, recovery time, overall study time, and mean dosage of dobutamine and atropine. In patients not on beta‐blocker medication, handgrip exercise should be routinely incorporated into all DASE protocols.
Rationale and design of the randomized, multicenter, Cilostazol for restenosis (CREST) trial
Authors: Douglas John S. , Weintraub William S. , Holmes David 
Published: June 2007

AbstractRestenosis of a segment of diseased coronary artery following metallic stenting is a common clinical problem and a major limitation of the procedure. Systemic pharmacologic interventions to deal with this problem have met with little success. Several small studies suggest that cilostazol, a phosphodiesterase III inhibitor whose pharmacologic properties include antiplatelet, antithrombotic, and vasodilatory effects; a beneficial effect on serum lipids; and in vitro inhibition of smooth muscle cell proliferation, may help prevent platelet aggregation and impede the accumulation of new intimal tissue in the stented artery. The Cilostazol for RESTenosis (CREST) trial will aim to evaluate more definitively the ability of cilostazol to prevent restenosis following uncomplicated stent implantation for de novo coronary artery stenosis. In this randomized, double‐blind, multicenter study, 700 patients will receive clopidogrel, aspirin, and either cilostazol or placebo after successful intracoronary stent implantation. The primary endpoint is minimal luminal diameter (MLD) of the first lesion stented after 6 months; secondary endpoints include MLD in all lesions, mean percent diameter stenosis, target lesion revascularization, and major angiographic endpoints. Safety endpoints are abnormal complete blood count and liver function tests at 1, 3, and 6 months. The trial has been initiated, and enrollment is anticipated to be concluded in 2003. Cilostazol has properties that may reduce or avert in‐stent coronary restenosis. The CREST trial is a large, rigorously conducted trial that may corroborate the favorable effects of cilostazol on coronary stent restenosis suggested by earlier studies.
Magnetocardiography in coronary artery disease with a new system in an unshielded setting
Authors: Hailer Birgit , Chaikovsky Illja , Auth‐Eisernitz Sabine , Schäfer Harald , Steinberg Fritz , Grönemeyer Dietrich H. W. 
Published: June 2007

AbstractBackground: The noninvasive detection of coronary artery disease (CAD) remains a clinical challenge. Magnetocardiography is a completely noninvasive method that permits the registration of cardiac electrical activity at multiple sites in a plane above the chest cage without the need for electrodes. In contrast to the electrocardiogram (ECG) which suffers from boundary effects and a variety of potential artifacts (electrode placement, etc.) the MCG is unaffected by such impediments as the magnetic field is unaltered by surrounding tissues.Hypothesis: Magnetocardiography with a newly developed single‐channel system in an unshielded setting should be a better qualitative diagnostic tool than the standard ECG for the detection and assessment of CAD.Methods: In all, 52 patients with angiographically documented CAD and unimpaired ventricular function as well as 55 controls were included in this study. A standard 12‐lead ECG was obtained in all subjects. The MCG recordings were taken from 36 positions under resting conditions. From these, current density vector maps were generated during the ST‐T interval. Each map was then classified using a classification system with a scale from 0 (normal) to 4 (grossly abnormal).Results: While the ECG was normal in all subjects, the MCG in the controls was classified as category 0, 1, or 2. However, in patients with abnormal coronary angiograms, mainly maps in categories 3 and 4 were seen (p < 0.05).Conclusion: A single‐channel magnetometer in an unshielded setting reveals significant differences between normals and patients with CAD with normal ECG on the basis of current density reconstruction during the ST segment when measured under resting conditions. This method might be suitable for the noninvasive detection of CAD.
Differential effects of simvastatin and atorvastatin on high‐density lipoprotein cholesterol and apolipoprotein A‐I are consistent across hypercholesterolemic patient subgroups
Authors: Davidson Michael H. , Ose Leiv , Frohlich Jiri , Scott Russell S. , Dujovne Carlos A. , Escobar Ivan D. , Bertolami Marcelo C. , Cihon Frank , MacCubbin Darbie L. , Mercuri Michele 
Published: June 2007

AbstractBackground: In addition to lowering plasma levels of low‐density lipoprotein cholesterol (LDL‐C), statins also raise high‐density lipoprotein cholesterol (HDL‐C).Hypothesis: Recent studies have shown that treatment with simvastatin results in larger increases in HDL‐C than those seen with atorvastatin. The results of three clinical studies are analyzed, comparing the effects of simvastatin and atorvastatin on HDL‐C and apolipoprotein A‐I (apo A‐I) in the total cohort and in several subgroups of hypercholesterolemic patients. The three studies were all multicenter, randomized clinical trials that included simvastatin (20–80 mg) and atorvastatin (10–80 mg) treatment arms. The subgroup analyses performed were gender; age (<65 and ≥65 years); baseline HDL‐C (male: < 40 or ≥ 40 mg/dl; female: < 45 or ≥ 45 mg/dl), baseline LDL‐C (< 160 or ≥ 160 mg/dl), and baseline triglycerides (< 200 or ≥ 200 mg/dl).Results: Both drugs produced similar increases in HDL‐C levels at low doses; however, at higher drug doses (40 and 80 mg), HDL‐C showed a significantly greater increase with simvastatin than with atorvastatin (p< 0.05 to <0.001). Therefore, while HDL‐C remained consistently elevated across all doses of simvastatin, there appeared to be a pattern of decreasing HDL‐C with an increasing dose of atorvastatin. A similar negative dose response pattern was also observed with apo A‐I in atorvastatin‐treated patients, suggesting a reduction in the number of circulating HDL particles at higher doses. Both drugs reduced LDL‐C and triglycerides in a dose‐dependent fashion, with atorvastatin showing slightly greater effects. The differential effects of atorvastatin and simvastatin on HDL‐C and apo A‐I were observed for both the whole study cohorts and all subgroups examined; thus, no consistent treatment‐by‐subgroup interactions were observed.Conclusion: The data presented show that, across different hypercholesterolemic patient subgroups, simvastatin increases HDL‐C and apo A‐I more than atorvastatin at higher doses, with evidence of a negative dose response effect on HDL‐C and apo A‐I with atorvastatin, but not simvastatin.
Insulin resistance and maximal oxygen uptake
Authors: Seibæk Marie , Vestergaard Henrik , Burchardt Hans , Sloth Carsten , Torp‐Pedersen Christian , Nielsen Steen Levin , Hildebrandt Per , Pedersen Oluf 
Published: June 2007

AbstractBackground: Type 2 diabetes, coronary atherosclerosis, and physical fitness all correlate with insulin resistance, but the relative importance of each component is unknown.Hypothesis: This study was undertaken to determine the relationship between insulin resistance, maximal oxygen uptake, and the presence of either diabetes or ischemic heart disease.Methods: The study population comprised 33 patients with and without diabetes and ischemic heart disease. Insulin resistance was measured by a hyperinsulinemic euglycemic clamp; maximal oxygen uptake was measured during a bicycle exercise test.Results: There was a strong correlation between maximal oxygen uptake and insulin‐stimulated glucose uptake (r = 0.7, p = 0.001), and maximal oxygen uptake was the only factor of importance for determining insulin sensitivity in a model, which also included the presence of diabetes and ischemic heart disease.Conclusion: Maximal oxygen uptake may be a more important determinant for insulin sensitivity than ischemic heart disease and type 2 diabetes.