bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Left and Right Pneumonectomy on Time‐ and Frequency‐Domain Parameters of Heart Rate Variability
Authors: Amar David , Zhang Hao , Leung Denis H.Y. , Ginsburg Iliana 
Published: October 2006

Background:Morbid cardiac events after pneumonectomy have been attributed to autonornic mechanisms. Analysis of heart rate variability (HRV) offers a noninvasive technique to assess modulation of sympathetic and parasympathetic activity. There is little data available on the systematic changes in time‐ and frequency‐domain parameters of HRV in response to pneumonectomy and cardiac plexus neural trauma. Methods:We measured HRV parameters in 54 patients undergoing left (n = 28) and right (n = 26) pneumonectomy (age 55 ± 11 years) who were without congestive heart failure, active ischemic heart disease, or dysrhythmias, and were not taking β‐blocker or calcium channel blocker therapy. Time‐ and frequency‐domain indices of HRV were measured before surgery (1 hour) and continuously after surgery (Holter) for 3 days. HRV indices measured were: mean R‐R interval (ms), mean of all 5‐minute standard deviation of R‐Rs (SDSD; ms); root mean square of difference of successive R‐Rs (rMSSD; ms); proportion of adjacent R‐Rs > 50 ms different (pNN50;%); total (TF; 0.01–1.00 Hz), low (LF; 0.04 ‐ 0.15 Hz) and high frequency (HF; 0.15–0.40 Hz) power (ms2). Results:Time (R‐R, SDSD, rMSSD, pNN50 and frequency (TF, LF, HF, LF/HF) indices of HRV decreased significantly in response to left or right pneumonectomy. The maximal decrease in HRV occurred during the first 24 to 48 hours. There were no differences between the groups in any measured HRV parameter. Mean heart rate ranged between 80 to 110 beats/min postoperatively for all patients. Conclusions:Decrements in time‐ and frequency‐domain indices of HRV occurred after pneumonectomy independently of the operative side. Global reductions in HRV after surgery support the presence of parasympathetic withdrawal. Although global changes in HRV may reflect an individual's response to surgical stress, the usefulness of HRV to study fine changes in physiological control mechanisms in the postoperative state appears limited. A.N.E. 1999;4(3):325–332
Exercise Electrocardiography Testing in Patients with Aortic Stenosis
Authors: Gencbay Murat , Degertekin Muzaffer , Ermeydan Cern , Unalp Aynur , Turan Fikret 
Published: October 2006

Background:Studies that have been conducted with exercise testing in patients with aortic stenosis (AS) have demonstrated that results of an exercise test can mimic coronary artery disease (CAD). The objective of our study was to investigate if there were any differential feature(s) of exercise testing in patients with AS compared to those with CAD. Methods:We prospectively studied 42 patients with AS (age 37 ± 23, range 8–75) with an averaged maximal gradient of 42 ± 19 mmHg (range 26–95). All patients had undergone a coronary angiography within 1 week of exercise testing and none had CAD. Another 100 patients with CAD, diagnosis proven with coronary angiography, comprised our second group for the comparison (CAD group). Cornell protocol was used in all patients. Results:ST segment depression was observed in all patients 160 ± 25 μV in AS group and 170 ± 20 μV in CAD group, P > 0.05). Thirty‐four (81%) patients in the AS group and 88 (88%) patients in the CAD group exceeded the classical threshold for the test positivity (P > 0.05), ST/HR slopes derived from heart rate adjustment to ST segment level did not differ between the study groups (3.2 ± 2.3 and 3.7 ± 2.2 μV/beat/min in AS and CAD groups, respectively, P > 0.05). Recovery phase patterns of ST segment in heart rate domain were different between AS and CAD (clockwise loop: 86% vs 0%; counterclockwise loop: 9% vs 88% in AS group and CAD group, respectively, both P < 0.001) Percentage of the intermediate loop was 5% in the AS group and 12% in the CAD group. Conclusions:Our study demonstrated that patients with AS could be distinguished from those with CAD with the method of rate‐recovery loop analysis. A.N.E. 1999;4(3):333–339
Nighttime Differential Autonomic Modulation of Sinus and Idioventricular Automaticity and of Atrioventricular Nodal Conduction
Authors: Mendoza Ivan J. , Castellanos Agustin , Lopera Gustavo , Moleiro Federico , Interian Alberto , Myerburg Robert J. 
Published: October 2006

Background:Potential differential effects of the autonomous nervous system on sinus node and protected idioventricular automaticity and on atrioventricular nodal conduction have not been assessed in the same patients. Methods:The sinus cycle lengths, parasystolic cycle lengths, uncorrected QT intervals, and PR intervals were measured in control epochs and epochs of transient spontaneous maximal nighttime heart rate accelerations occurring between 1 and 4 AM. Noncontiguous epochs were selected to avoid potential accommodation‐like, or memory effects that could occur at the moments of abrupt acceleration or decelerations of sinus rate. Results: The longest sinus cycle lengths coincided with the longest parasystolic cycle lengths and uncorrected QT intervals, whereas the shortest sinus cycle lengths coexisted with the shortest parasystolic cycle lengths and the shortest QT intervals. In contrast, the PR intervals did not show a uniform behavior during the episodes of transient heart rate accelerations since they could increase, decrease, or remain the same. Conclusion: The different behavior of cycle lengths and PR intervals during nighttime heart rate increases, suggests that the autonomic modulation of the sinus node, idioventricular focus, and the AV node can be independent from each other. A.N.E. 1999;4(4):385–390
Prognostic Significance and Long‐term Natural History of Heart Rate Variability in Survivors of First Myocardial Infarction
Authors: Johansen Allan , Mickley Hans , Junker Anders , Møller Mogens 
Published: October 2006

Background:Reduced heart rate variability (HRV) is an established predictor of mortality after acute myocardial infarction (Ml). HRV is reduced early after Ml and begins to recover within a few weeks, reaching a plateau 3 to 6 months later and remains stable in the first year after Ml. How HRV develops during serial recordings beyond 1‐year follow‐up has not been studied. Methods:Serial 24‐hour Holter monitoring (discharge, 6 months, 1, 2, and 3 years) was performed in 123 patients recovering from a first acute Ml. During 6 years of follow‐up, 73 patients were free from subsequent events (mortality, nonfatal reinfarction, or coronary revascularization). The prognostic importance of early HRV values for the total group was assessed, and potential long‐term changes in HRV measurements in the 73 event‐free patients were studied. Results:HRV values at discharge (SDNN and HRV triangular index) were reduced compared with the findings in healthy controls, and the measurements predicted future mortality. In event‐free patients, SDNN and HRV triangular index improved over the following months, but the values did not reach the level of healthy controls, even at late follow‐up. No changes in HRV measurements were found between 1 and 3 years. Conclusions: Measurement of HRV is a useful tool in the prediction of mortality after first acute Ml. During the first few months an improvement in HRV is observed. The results of late serial recordings, however, demonstrate no additional changes in HRV values. Even at 3 years, HRV measurements did not reach the qualitative level of healthy controls. A.N.E. 1999;4(4):391–396
Reevaluation of an Old Electrocardiographic Criterion for Coronary Disease: TV1 > TV6
Authors: Nalbantgil Sanem , Yilmaz Hasan , Gurgun Cemil , Gurcay Bulent , Zoghi Mehdi , Nalbantgil Istemi , Onder Remzi 
Published: October 2006

Background:Two different studies were conducted to evaluate the value of T wave in V1 taller than T wave in V6 (TV1 > TV6) pattern as an indicator of coronary artery disease. Method: In the first study 5,300 resting ECGs were examined and the criterion was found in 283 patients. All of these patients were examined with echocardiography. In the second study, ECG tracings and coronary angiograms of another 500 patients were evaluated. Results:In the first study, in 59 of 283 patients left ventricular hypertrophy was detected and these patients were excluded from the study. There were ST segment‐T wave changes and/or Q wave on ECG suggesting coronary ischemia or myocardial infarction in 160 of the 224 patients. TV1, > TV6 criterion was the sole finding in 64 of the 224 patients. All of the 224 patients underwent coronary angiography and coronary artery disease was detected in 185 patients; 134 of the 160 patients (83.3%) and 51 of 64 patients (80%) had one‐vessel or multivessel disease. There was no significant difference among the groups regarding coronary artery disease. Left anterior descending artery was involved in all of the 185 patients. In the second study, 408 patients were found to have coronary disease involvement and 92 patients showed normal or insignificant coronary disease. Sixty‐six of the 408 patients with coronary disease and four of 92 patients were found to have the TV1 > TV6 pattern. Sensitivity of the criterion was 16.1%, specificity was 95.6%, and accuracy was 94.2%. Conclusions: According to these results, it is concluded that TV1 > TV6 with or without other ECG findings is a good criterion suggesting coronary artery disease, especially left anterior descending artery involvement in patients without left ventricular hypertrophy. A.N.E. 1999;4(4):397–400
QT Dispersion as a Noninvasive Arrhythmiogenic Marker in Acute Myocardial Infarction
Authors: Papandonakis Emmanuel , Tsoukas Athanasios , Christakos Stamatios 
Published: October 2006

Backround: Prolongation of QT dispersion (QTD), defined as the difference between maximum and minimum QT intervals on surface ECG, has been proposed as a noninvasive arrythmogenic marker. The aim of this study was to estimate the value of QTD in identifing patients susceptible to ventricular fibrillation or ventricular tachycardia (VF/VT) after an acute myocardial infarction (AMI) and to evaluate the behavior of QTD in relation to the thrombolytic therapy.Methods: We studied 108 consecutive patients with AMI. All patients had a 12‐lead surface ECG recorded upon admission and a second ECG 24 hours later. QT interval was measured from the onset of Q to the end of T in each of 12 standard ECG leads. QTD was the difference between the longest and shortest values of QT. All QTD measurements were corrected for heart rate (QTcD) using QTc values according to Bazzet formula.Results: Fifteen patients (13.8%) developed VF/VT in the first week after AMI (group 1A) and 93 patients (86.2%) did not have VF/NT (group 1B). QTD and QTcD values were significantly greater in group 1A in comparison to group 1B on admission and 24 hours later. Sixty‐five patients (60%) received intravenous thrombolysis in the acute phase of AMI (group 2A) and 43 patients (40%) did not (group 2B). No significant difference in QTD and QTcD was observed in the first ECG on admission between the two groups. Conversely, QTD and QTcD were lower in group 2A patients in the second ECG 24 hours after admission.Conclusions: These results provide evidence that increased values of QTD are correlated well with occurrence of malignant ventricular arrhythmias after acute myocardial infarction while lower values associated with the thrombolytic therapy. A.N.E. 1999;4(1):35–38
Assessment of Multivessel Coronary Artery Disease by Means of Stress‐Recovery ST/HR Index in Postinfarction Patients on Beta‐Blocker Therapy
Authors: Bigi Riccardo , Curti Gianpiero , Sponzilli Carlo , Fuscaldo Giuseppe , Occhi Giuseppe , Fiorentini Cesare 
Published: October 2006

Objective: The aim of this study was to evaluate the influence of pharmacological therapy on the assessment of coronary anatomy by means of, respectively, conventional ST depression and comparative heart‐rate adjusted ST segment (ST/HR) analysis during exercise and recovery following acute Ml.Background: The withdrawal of therapy before stress testing is controversial. We previously demonstrated that a simple continuous variable (Stress‐Recovery Index [SRI] defined as the difference between the areas subtended to baseline and limited by ST trend against HR during exercise and recovery) can substantially improve the post‐MI identification of multivessel disease (MVD).Methods: Seventy‐five patients underwent maximal exercise ECG test on and off beta‐blockers with or without additional therapy, in random sequence, within 2 weeks of infarction. Coronary angiography was done within 1 month. The test was considered positive for increased risk of MVD in case of ST depression < 2 mm and, respectively, SRI > 5 mm × beats × min−1, as previously suggested.Results: Off therapy, ST depression was positive in 33 and negative in 42 patients, while SRI was positive in 35 and negative in 40; on therapy, ST depression was positive in 21 and negative in 54 patients, while SRI was positive in 44 and negative in 31. Forty‐four subjects had MVD. The sensitivity and specificity of SRI were, respectively, increased and reduced by therapy, while an opposite effect was found on ST depression. SRI on therapy was more sensitive (P > 0.001) and less specific (P > 0.05) than ST depression and was the most sensitive parameter in identifying only 3‐vessel. Positive ST depression and negative SRI on therapy were associated, respectively, with the highest and lowest Gensini's score.Conclusions: The SRI is superior to ST depression in identifying complex coronary anatomy in post‐Ml patients, especially during beta‐blockade therapy. A.N.E. 1999;4(1):60–66
Comparison of Baroreflex Sensitivity with Age and Indices of Left Ventricular Function in Patients with Dilated Cardiomyopathy
Authors: Menz Volker , Hoffmann Jürgen , Grimm Wolfram , Born Stephan , Mey Nadja , Glaveris Christina , Maisch Bernhard 
Published: October 2006

Background: BRS is an index of autonomic innervation of the heart. Depression of the BRS after Ml is correlated with an increased risk of cardiac mortality and sudden death. However, little is known about the BRS in patients with idiopathic dilated cardiomyopathy (IDC).Methods: In a prospective study the BRS was measured in 89 patients with IDC by the noninvasive phenylephrine method. Mean age of the study population was 48 years, LVEF was 30.2 ± 9.5 %, and left ventricular enddiastolic diameter was 66.9 ± 7.6 mm.Results: BRS did not significantly differ in patients with an LVEF > 30% compared to patients with an ejection fraction 30% (6.2 ± 4.1 vs. 7.3 ± 3.6 ms/mmHg, P > 0.05). There was no difference in the BRS slope between patients with a left ventricula‐ end‐diastolic diameter 65 mm compared to > 65 mm (6.4 ± 3.2 vs. 7.0 ± 4.4 ms/mmHg, P < 0.05) and in patients older than 50 years of age compared to younger patients (6.1 ± 3.7 vs. 7.3 ± 4.0 ms/mmHg, P < 0.05).Conclusion: BRS may be an independent parameter useful for risk stratification in patients with dilated cardiomyopathy. A.N.E. 1999;4(1):67–71
Prognostic Significance of QTc Interval for Predicting Total, Cardiac, and Ischemic Heart Disease Mortality in Community‐Based Cohort from Warsaw Pol‐MONICA Population
Authors: Pytlak Aleksandra , Piotrowski Walerian 
Published: October 2006

Background: QT interval in resting electrocardiogram (ECC) is a sum of ventricular depolarization and repolarization time. Its prolongation is associated with a worse prognosis for survival due to a high incidence of severe ventricular arrhythmias.Methods: The random sample of the Warsaw Pol‐MONICA population consisting of 2646 men and women, aged 35–64, screened in 1984, was followed‐up until 1996. All deaths and their causes were registered based on death certificate diagnosis. QT interval was measured manually in three consecutive QRST complexes in each ECG and corrected using Bazett's formula (QT corrected: QTc). For statistical analyses the mean value of 3 QTc measurements were used. To assess the relationship between QTc and mortality, the Cox proportional hazards model with stepwise selection of variables was used.Results: Out of the screened sample, 459 persons died (309 men, 150 women), 226 due to cardiovascular diseases (CVD) (162 men, 64 women), and 81 due to ischemic heart disease (IHD) (59 men, 22 women). Both men and women who died were significantly older at baseline and had significantly longer mean QTc as compared to survivors (men: 457 ms vs 446 ms, P = 0.0001; women: 469 ms vs 459 ms, P = 0.001). Among men, after adjustment for confounding variables, mean QTc was significantly associated with total and CVD mortality, and in women, with CVD and IHD mortality. The risk of death rose with an increase in QTc duration. In men, with every increase in QTc by 20 ms, the risk of all causes of death rose by 11% (95% CI: 1.04–1.18), CVD death by 9% (95% Cl: 1.01–1.19), and IHD death by 11 % (95%: 0.97–1.28). In women, the risk of all‐cause death increased by 9% (95% CI: 0.98–1.21), CVD death by 21% (95% Cl: 1.02–1.43), and IHD death by 41% (95% Cl: 1.08–1.85).Conclusion: QTc interval was significantly related to all cause, cardiovascular and ischemic heart disease. The risk of death increased with longer QTc duration. A.N.E. 2000;5(4):322–329
Impedance Cardiographic Findings in Electrocardiographically Diagnosed Acute Right Ventricular Infarction
Authors: Tore Hasan Fehmi , Uzun Mehmet , Erinc Kursad , Kirilmaz Ata , Barcin Cem , Baysan Oben , Barindik Nadir , Demirtas Ertan 
Published: October 2006

Background: Thorax impedance cardiography (TIC) can provide important information about the hemodynamic state of patients. In this study, we aimed at finding out if TIC can be used in the early follow‐up of acute right ventricular myocardial infarction (RVMI).Methods: The study consisted of patients with RVMI who were admitted to our coronary care unit between March 1998 and October 1999. The patients were divided into two groups: group A: patients with hemodynamically significant RVMI, and group B: patients with hemodynamically insignificant RVMI. All impedance measurements were performed with the commercially available device BoMed NCCOM3. We measured stroke volume index, cardiac index and ejection fraction by TIC. The measurements were done on the day of admittance (day O), first day and second day continuously, and on the third to fifth day during bed rest. Comparisons of TIC measurements and vital signs were made by Friedman analysis. Group A and group B were compared by Mann Whitney U test and chi square. The level of statistical significance was set at P < 0.05.Results: There were 26 patients in group A (mean age: 62 ± 10) and 14 patients in group B (mean age: 61 ± 12). There were no statistically significant differences between the groups in age and sex. There were statistically significant differences between group A and B with regard to stroke volume index (32 ± 5 vs 28 ± 5; P = 0.0147), total peripheral resistance (19 ± 5 vs 23 ± 5; P = 0.0084); ejection fraction (0.44 ± 0.16 vs 0.58 ± 0.08; P = 0.0131). The vital signs with statistically significant differences were systolic arterial blood pressure (110 ± 17 vs 88 ± 7, P < 0.0001); diastolic arterial blood pressure (72 ± 12 vs 55 ± 13; P = 0.0002) and heart rate (89 ± 12 vs 71 ± 11; P < 0.0001). The differences disappeared on the second day. The lack of significance continued on the fifth day. Friedman analysis revealed that all the TIC parameters except for left ventricular ejection fraction change towards the normal range. Ejection fraction did not change in group B but decreased in group A on the second day; however it was stable later.Conclusion: TIC can provide easily obtained parameters which may have a role in the treatment of hemodynamically significant RVMI. This is particularly important in coronary care centers with limited invasive capabilities. A.N.E. 2000;5(4):330–335
Early Antiarrhythmic Therapy Is No Better than Rate Control Therapy Alone for Suppression of Atrial Fibrillation After Cardiac Surgery
Authors: Melecio Abordo M.D.  , Soucier Richard , Berns Ellison , Silverman David I. 
Published: October 2006

Background: Despite recent advances in therapy for atrial fibrillation (AF) following cardiac surgery, the potential superiority of antiarrhythmics over rate control therapy for suppression of AF has not been convincingly demonstrated. We sought to determine whether early treatment of AF following cardiac surgery with antiarrhythmics improves clinical outcome, as measured by recurrence rate, length of stay, and adverse events.Methods: Out of 1100 consecutive patients undergoing cardiovascular surgery from July 1997 to June 1998, AF was identified in 425 (38.6%) prior to discharge. Patients with a history of chronic AF prior to cardiovascular surgery and patients who died within 48 hours of cardiovascular surgery were excluded from the analysis; 365 patients were studied. Group I patients received rate control alone; Group II received antiarrhythmic drugs within 24 hours of the first onset of AF.Results: With the exception of frequency of pulmonary disease (4 vs 17, P = 0.009), CABG rate (35 vs 45%, P = 0.045), and rate of valve surgery (24 vs 15%, P = 0.028), there were no significant differences in clinical characteristics between the two groups. The rate of return to sinus rhythm within 24 hours (80 vs 82%), and the percentage of patients leaving the hospital in sinus rhythm (90 vs 92%) were similar between the two groups, as were total length of stay (10.6 ± 6.0 vs. 11.4 ± 5.8, P = 0.159) and postoperative length of stay (8.4 ± 15.0 vs. 9.4 ± 5.3, P = 0.061). Embolic event rates were similar in both groups (eight in Group I and three in Group II). Proarrhythmia occurred in two patients receiving early antiarrhythmic therapy.Conclusion: Traditional use of early antiarrhythmic therapy appears to provide no clear advantage to rate control after cardiovascular surgery in terms of length of stay, freedom from AF at discharge, and other common clinical outcomes. Routine use of antiarrhythmics for suppression of AF should be carefully reconsidered. A.N.E. 2000;5(4):365–372
Prevalence of Spectral Turbulence and Late Potentials in a Random Population Sample
Authors: Gottfridsson Christer , Beckman‐Suurküla Marie , Karlsson Thomas , Wilhelmsen Lars , Edvardsson Nils 
Published: October 2006

Background:Late potentials (LP) and spectral turbulence (STU) in the signal‐averaged ECG (SAECG) in patients with heart disease mark a risk of malignant ventricular arrhythmias. The prevalence and cause of STU in otherwise healthy subjects have not been established. Methods:The SAECGs of a randomly selected population sample without known heart disease, 55 men and 66 women aged 50 ± 10 years, were analyzed for LP and STU. An STU score > 1 qualified for an echocardiographic examination (echo) and a 24‐hour Holter ECG (Holter). Results:The QRS duration in lead V2 in men was 99.5 ± 8.5 ms (mean ± SD) vs 94.2 ± 8.5 in women, P = 0.0008. The QT end was 406.7 ± 27.0 ms in women and 394 ± 24 in men, P = 0.01. The FQRSD (40 Hz) was 98.0 ± 8.6 ms in men vs 90.2 ± 9.0 in women, P = 0.0001. Subjects > 50 years of age had a lower RMS40 (33.0 ± 16.3 μV) than subjects < 50 years (40.2 ± 18.3 μV, P = 0.02). Nine (7%) subjects were LP‐positive. The STU score variables LSCR, ISCM, ISCSD and SE were positive in 12 (10%), 13 (11 %), 41 (34%) and 17 (14%) of the subjects, respectively. The mean spectral score was 0.69 ± 0.98. Eight (7%) subjects had a score of 3 or 4, considered STU‐positive. No correlation between score and gender, age or 12‐lead QRS duration was found. In score > 1, 27 (84%) had a completely normal ECHO and 31 (86%) a normal Holter. Cardiac dimensions measured by ECHO correlated with SAECG variables. Conclusions: Men had a longer mean QRS duration than women. Women had longer mean QT and JT intervals than men, which might imply an increased risk during antiarrhythmic therapy. The STU variables were not gender‐ or age‐dependent. The variable ISCSD was positive in as many as 41 (34%) presumably healthy subjects and did not seem to be a useful variable. Seven percent of the subjects were spectral turbulence‐positive and 7% were LP‐positive. A.N.E. 2000;5(1):30–38