bluuebunny/crossref_metadata_2025_split huggingface dataset:
Successful external cardioversion of atrial fibrillation in patients referred to an electrophysiologist for internal cardioversion
Authors: Verdino Ralph J. , Teuteberg Jeffrey J. , Burke Martin C. , Kopp Douglas E. , Timothy Johnson C. , Lin Albert C. , Alberts Michael , Kall John G. , Wilber David J. 
Published: February 2009

AbstractBackground: Internal cardioversion of atrial fibrillation with direct current energy has become an increasingly employed technique for patients who fail external cardioversion.Hypothesis: The purpose of this study was to determine whether internal cardioversion could be avoided by careful attention to cardioversion technique in a group of patients referred specifically for internal cardioversion after failed external cardioversion by community cardiologists.Methods: We performed external cardioversion utilizing two operators applying significant pressure to the thorax with up to 360 J prior to the planned internal cardioversion in 20 patients referred for internal cardioversion after failed attempts at external cardioversion.Results: Sixteen patients (80%) were successfully cardioverted and avoided the risk, inconvenience, and cost of internal cardioversion.Conclusion: External cardioversion with significant anterior paddle pressure by two operators can decrease the need for internal cardioversion in a significant portion of patients referred to electrophysiologists for internal cardioversion and should be considered prior to an invasive procedure.
Effect of verapamil on prevention of atrial fibrillation in patients implanted with an implantable atrial defibrillator
Authors: Tse Hung‐Fat , Wang Qlong , Yu Cheuk‐Man , Ayers Gregory M. , Pak Chu‐ 
Published: February 2009

AbstractBackground: The role of verapamil in the prevention of atrial fibrillation (AF) in patients with recurrent AF is unknown.Hypothesis: The aim of this study was to evaluate the effect of verapamil on the prevention of AF in patients implanted with an implantable atrial defibrillator (IAD).Methods: The effects of verapamil (240 mg/day) on the total duration of AF, number of AF recurrences, and number of cardioversions were prospectively evaluated in a randomized, crossover fashion over an 8‐week period in 11 patients (9 men, 2 women; mean age: 60 ± 6 years) implanted with an IAD.Results: Implantable atrial defibrillators successfully converted 13 of 14 (93%) spontaneous episodes of AF. There was no significant difference in the efficacy of cardioversion (86 vs. 100%, p = 0.8), the total duration of AF (173 ± 198 vs. 270 ± 241 h, p = 0.5), the number of AF episodes (8.5 ± 9.0 vs. 9.3 ± 10.2, p = 0.3), and the number of cardioversions (1.7 ± 2.4 vs. 1.8 ± 2.1, p = 0.7) with or without treatment with verapamil.Conclusions: The results of the present study suggest that treatment with verapamil has no significant effect on the prevention of AF in patients treated with an IAD.
Spinal cord stimulation for chronic intractable angina pectoris: A unified theory on its mechanism
Authors: Latif Osman A. , Nedeukovic Srdjan S. , Stevenson Lynne Warner 
Published: February 2009

AbstractThe use of spinal cord stimulation (SCS) for chronic intractable anginal pain was first described in 1987. Numerous studies have demonstrated its efficacy in improving exercise tolerance, decreasing frequency of anginal episodes, and prolonging time to electrocardiographic signs of ischemia. This review will examine the potential mechanisms of this antianginal effect and propose a unified hypothesis explaining it. The effect of SCS involves a mutual interaction of decreased pain, decreased sympathetic tone, and a likely redistribution of myocardial blood flow to ischemic regions. Spinal cord stimulation reduces the transmission of nociceptive impulse via the spinothalamic tract due to an enhanced release of gamma aminobutyric acid (GABA) from dorsal horn interneurons. Improvement of myocardial blood flow at the microvascular level has been demonstrated by positron emission tomography (PET). A decreased sympathetic tone has been shown by norepinephrine kinetics, tests of sympathetic reflexes, and the use of ganglionic blockers. We hypothesize that SCS exerts its beneficial effects by decreasing pain and decreasing sympathetic tone, the result of which is decreased myocardial oxygen consumption along with an improved myocardial microcirculatory blood flow.
Obesity is associated with premature occurrence of acute myocardial infarction
Authors: Suwaidi Jassim Al , Scott WRIGHT R. , Grill Joseph P. , Hensrud Donald D. , Murphy Joseph G. , Squires Ray W. , Kopecky Stephen L. 
Published: February 2009

AbstractBackground: The American Heart Association has classified obesity as a major modifiable risk factor for coronary artery disease, but its relationship with age at presentation with acute myocardial infarction (AMI) is poorly documented.Hypothesis: The study was undertaken to evaluate the impact of obesity on age at presentation, and on in‐hospital morbidity and mortality in patients with AMI.Methods: Our analysis includes a consecutive series of 906 Olmsted County patients (mean age 67.7 years, 51% male) admitted with AMI to the Mayo Clinic Coronary Care Unit (CCU). The patients were entered into the Mayo CCU Database, a prospective registry of data pertaining to patients admitted to the Mayo Clinic CCU with AMI. Age at AMI occurrence and in‐hospital morbidity and mortality were noted.Results: Obese patients (body mass index [BMI] >30) with AMI were significantly younger than patients with AMI in the overweight (BMI 25–30) and normal‐weight (BMI <30) groups (62.3 ± 13.1 vs. 66.9 ± 13.2 and 72.9 ± 13.4, respectively, p < 0.001). Obesity and overweight status were associated with male gender, diabetes mellitus, hypercholesterolemia, and smoking history; however, after multivariate adjustment for these risk factors, excess weight and premature AMI remained significantly associated. Compared with normal‐weight patients, overweight patients presenting with AMI were 3.6 years younger (p < 0.001, confidence interval [CI] 1.9–5.4) and obese patients 8.2 years younger (p < 0.001, CI 6.2–10.1). No significant increase in in‐hospital morbidity and mortality was seen.Conclusion: In this population‐based study, overweight and obese status are independently associated with the premature occurrence of AMI, but not with an increased incidence of in‐hospital complications.
Exceptional prevalence of interatrial block in a general hospital population
Authors: Jairath Umesh C. , Spodick David H. 
Published: February 2009

AbstractBackground: Interatrial block (IAB: P wave ≥ 110 ms) is a strong correlate of left atrial (LA) enlargement and an important predictor of supraventricular tachyarrhythmias, notably atrial fibrillation and flutter. It is surprising that, despite its association with arrhythmias and its effects on the electromechanical properties of the left atrium, there is widespread neglect of this common abnormality.Hypothesis: The study was undertaken to investigate the prevalence of IAB in a general hospital population.Methods: We prospectively evaluated the electrocardiograms of 1,000 consecutive adult patients, analyzed for P‐wave duration.Results: Our results showed a very high prevalence of IAB (41.1% of patients in sinus rhythm and 32.8% of all patients). As expected, it was more common in patients aged > 60 years.Conclusions: Given this unusually high prevalence of IAB in hospital patients and its ominous portents (LA enlargement, thrombosis and embolism, arrhythmias), physicians should be aware of its frequency and computer software should be programmed to recognize it.
Long‐term follow‐up after deferring angioplasty in asymptomatic patients with moderate noncritical in‐stent restenosis
Authors: Lee Jae‐Hwan , Lee Cheol Whan , Park Seong‐Wook , Hong Myeong‐Ki , Kim Jae‐Joong , Rhee Kyoung Suk , Park Seung‐Jung 
Published: February 2009

AbstractBackground: Many patients with in‐stent restenosis (ISR) are angina‐free, but the optimal treatment for these patients remains uncertain.Hypothesis: In cases with asymptomatic moderate noncritical ISR, deferral of the intervention may be safe and associated with favorable clinical outcome.Methods: We evaluated the long‐term clinical outcome of asymptomatic patients (Group 1, n = 98) with moderate non‐critical ISR (< 70% diameter stenosis) after intervention was deferred, and compared it with that of patients (Group 2, n = 655) without restenosis. After repeat angioplasty was deferred, all patients were treated medically and later underwent angioplasty only in the case of clinical recurrence.Results: Baseline characteristics were similar between the two groups. Clinical follow‐up was available in all patients at 26.3 ± 15.9 months. Twenty patients died during the follow‐up: 1 in Group 1 and 19 in Group 2. Target lesion revascularization was performed in 3 patients in Group 1 and 11 patients in Group 2 during follow‐up (p = NS), and new lesion revascularization in 2 patients in Group 1 and 27 patients in Group 2 (p = NS). Event‐free survival rate (cardiac death, nonfatal myocardial infarction, repeat revascularization) was 86.7 ± 6.1% in Group 1 and 84.8 ± 2.2% in Group 2 at the end of follow‐up (p = NS). Major adverse cardiac events were only associated with the presence of diabetic mellitus (hazards ratio 2.65,95% confidence interval [CI] 1.48–4.73, p < 0.01). The percentage of patients receiving antianginal medication was similar between the two groups at the end of the study (p = NS).Conclusions: Asymptomatic patients with moderate non‐critical ISR have a good prognosis and similar clinical outcome as those without ISR, suggesting that it may be safe to defer repeat angioplasty in these patients until angina recurrence.
Development and validation of the ITG health‐related quality‐of‐life short‐form measure for use in patients with coronary artery disease
Authors: Buchner Deborah A. , Graboys Thomas B. , Pharm Kiel Johnson, , Mordin Margaret Mcgrath , Goodman Linda , Partsch Deborah S. , Goss Thomas F. 
Published: February 2009

AbstractBackground: Available coronary artery disease (C AD)‐specific health‐related quality‐of‐life (HRQL) measures are not ideally suited for routine clinical practice. We report development of a valid and reliable CAD‐specific short‐form measure.Hypothesis: The Integrated Therapeutics Group (ITG) CAD‐specific short‐form HRQL measure is reliable and valid for assessing the health status of patients with CAD.Methods: In all, 409 patients (mean age 62.4 years) completed the 24–item CAD‐specific HRQL questionnaire. Factor analysis was used to identify the scaling of the 24 CAD‐specific items. Analysis of variance was used to reduce the number of items within each scale, and reliability (Cronbach's a), discriminant validity, and ceiling and floor effects of short‐form scales were evaluated. Short‐form scales were compared with the longer scales using relative validity coefficients. The CAD severity was assessed using New York Heart Association criteria, physician assessment, electrocardiogram results, the number of myocardial infarctions, and the number of CAD‐specific medications. Clinical validity of short‐form scales was then assessed based on their ability to discriminate across severity levels of these clinical criteria.Results: Four scales were identified: Extent of Chest Pain, Functioning and Weil‐Being, Activities Level‐Physical, and Activities Level‐Social. The 24‐item questionnaire was reduced to a 13‐item short form, with reliability exceeding 0.70 for all four scales. Relative validity estimates comparing short‐form to original scales ranged from 0.68 to 2.58. Mean scores varied significantly (p < 0.05) by clinical severity, supporting the discriminant validity of the ITG CAD short‐form scales.Conclusions: The ITG CAD short form (used alone or with a general HRQL measure) is valid and practical for assessing patients with CAD.
Left atrial size in 164 hypertensive patients: An echocardiographic and ambulatory blood pressure study
Authors: Tedesco Michele A. , Salvo Giovanni Di , Ratti Gennaro , Natale Francesco , Iarussi Diana , Iacono Aldo 
Published: February 2009

AbstractBackground: Left atrial enlargement (LAE) is associated with an increased risk of death and cardiovascular (CV) hospitalization. Whether or not LAE reflects early structural change from hypertension is unclear.Hypothesis: The aim of this study was to evaluate the relationship between LA size, 24‐h blood pressure measurements, age, body mass index (BMI), and left ventricular mass index (LVMI) in hypertensive patients.Methods: We studied 164 outpatients (age range 30–76 years, 73 men and 91 women) with mild to moderate hypertension. Physical examination, electrocardiogram, noninvasive blood pressure monitoring (ABPM), Doppler echocardiogram were performed. Left ventricular mass index and LA dimensions were calculated. The sample was divided by age (< 60 and ≥ 60 years).Results: Left ventricular hypertrophy (LVH) was present in 45% of patients aged < 60 years and in 70% of patients aged ≥60 years (p = 0.002). Left atrial enlargement (>4 cm) was present in 35% of elderly and in 24% of young patients (p = 0.31), and in 36% of patients with and 21 % of patients without LVH (p = 0.0057). There was no significant difference in the younger patients with and without LVH. The incidence of obesity was low (31 %) in the whole sample. The percentage of overweight in the elderly patients with LVH and higher LA size was equally low. Multivariate analysis showed age (p = 0.044) and LVMI (p = 0.002) as the only significant predictors of LA enlargement.Conclusion: Since LAE is associated with a high risk of death and CV hospitalization, we emphasize the importance of development and use of drugs that inhibit LVH.
Psychological distress across the course of care: A case study from implantable cardioverter defibrillator to cardiac transplantation evaluation
Authors: Eads Angela S. , Sears Samuel F. , Marhefka Stephanie , Aranda Juan , Schofield Richard , Conti Jamie B. 
Published: February 2009

AbstractThe psychological distress of cardiac patients can complicate treatment or the recovery process. This case study presents a 47‐year‐old male recipient of an implantable cardioverter defibrillator who experienced multiple, consecutive shocks and subsequently developed anxiety and depressive difficulties. Psychological treatment to diminish these symptoms was employed. Despite declining cardiac function, the patient made significant progress in managing this negative affect. Subsequently, he was evaluated for cardiac transplant, and this treatment progress became critical evidence of his psychosocial suitability for transplant.
An iatrogenic coronary arteriovenous fistula causing a steal phenomenon: An intracoronary doppler study
Authors: Wexberg Paul , Gottsauner‐Wolf Michael , Kiss Katharina , Steurer Günter , Glogar Dietmar 
Published: February 2009

AbstractWe present the case of a 67‐year‐old man in whom a guidewire broke at rotablation of the right coronary artery, creating an iatrogenic aneurysmal arteriovenous fistula to the coronary sinus. Successful Doppler wire‐guided fistula occlusion by percutaneous coil embolization lead to normalization of coronary blood flow and relief of the patient's symptoms. Myocardial ischemia in this patient may have been due to a steal phenomenon caused by coronary artery fistulae, as suggested by blood flow velocity data obtained before and after fistula occlusion.
Assessment of subclinical atherosclerosis and cardiovascular risk
Authors: Michael BENITEZ R. , Vogel Robert A. 
Published: February 2009

AbstractConventional cardiac risk factors do not fully explain the incidence of coronary artery disease and coronary events. Risk stratification and therapy based solely on these conventional risk factors may exclude a population who would otherwise benefit from lifestyle and risk factor modification. Recent efforts to improve our ability to recognize individuals and populations at increased risk of coronary events have focused on the noninvasive imaging of atherosclerosis, both in coronary and extracoronary arterial beds, or the identification of “non‐traditional” serum markers. We review the complimentary role of these newer methods of risk stratification in the context of conventional risk factor evaluation.
A Critique of the new ST‐segment criteria for the diagnosis of acute myocardial infarction in patients with left bundle‐branch block
Authors: Madias John E. , Sinha Anjan , Ashtiani Ramin , Agarwal Himanshu , Win Moethu , Narayan Virenjan K. 
Published: February 2009

AbstractBackground: Recently, electrocardiogram (ECG) criteria have been proposed for the diagnosis of acute myocardial infarction (AMI) in the presence of left bundle‐branch block (LBBB). However, clinical experience indicates that such ECG changes indicative of AMI are occasionally noted in clinically stable patients with LBBB, raising concerns about the specificity of the proposed criteria.Hypothesis: The aim of this study was to evaluate the frequency of ST‐segment abnormalities suggestive of AMI in ambulatory patients with cardiovascular disease and chronic LBBB, who did not have an AMI. In addition, the ECG determinants of such ST‐segment abnormalities were sought.Methods: The files of all (4,193) patients followed in the outpatient cardiology clinic were reviewed to identify patients with LBBB. Electrocardiograms of these patients were evaluated as to the duration of the QRS complex, frontal QRS axis, amplitude of QRS in leads V1‐V3, and the presence and magnitude of ST‐segment depression (‐ST) in leads V1‐V3, and ST‐segment elevation (+ST) in leads with predominantly positive or negative QRS complexes. Correlations of these ECG variables were carried out.Results: In 124 patients with LBBB only 1 patient with — ST of 1 mm in leads V1‐V3, and 1 patient with +ST of 1 mm in a predominantly positive ECG lead were found; the latter patient also had +ST of 6 mm in V3. Nine patients were detected with > 5 mm +ST in at least one ECG lead with predominantly negative QRS complex. Regression analysis of amplitude of +STS on corresponding QRS amplitudes in leads V1‐V3 yielded Rs of 0.69, 0.68, and 0.69, all with a p value of 0.00005. A similar analysis of the amplitudes of+STs > 5 mm with the corresponding QRSs yielded an R=0.76 and a p value of 0.0018.Conclusions: Thus, recently proposed ST‐segment criteria for the diagnosis of AMI in patients with LBBB are appropriate. However, stable > 5 mm +STs are occasionally found in leads with predominantly negative QRS complexes, particularly of large amplitude (mean value 46.0, range [28.0–71.0] mm) in the absence of AMI. In such patients presenting with symptoms suggestive of AMI, further non‐ECG confirmation of probable underlying AMI should be sought.
Power motion imaging can improve image quality in stress conditions with tachycardia
Authors: Nishino Masami , Youn Ho‐Joong , Gheorghevici Dorina , Zellner Christian , Chou Tony M. , Sudhir Krishnankutty , Redberg Rita F. 
Published: February 2009

AbstractBackgrvund: Stress echocardiographic studies are useful, but the evaluation of wall motion is sometimes suboptimal. The recently developed technique of power motion imaging can enhance mobile tissue definition.Hypothesis: The study was undertaken to determine whether power motion imaging improves endocardial definition during tachycardia compared with conventional two‐dimensional (2‐D) imaging.Methods: Twenty pigs were studied during pacing rates of 100, 120, and 150 beats/min. We compared power motion imaging with standard 2‐D imaging using systolic thickening visualization (STV) scores (3 = excellent definition of systolic thickening ˜ 0 = total lack of visualization of systolic thickening) at each heart rate. We calculated the sum of the scores of 22 left ventricular segments as the overall STV score, and also calculated the sum of the scores in 10 parasternal segments and 12 apical segments separately.Results: The overall STV scores in both imaging methods were similar at 100 beats/min, but scores for power motion imaging were significantly higher than those of usual 2‐D imaging at 120 and 150 beats/min. Using power motion imaging, the overall STV scores were similar as heart rate was increased; however, while using standard 2‐D imaging, STV scores were significantly decreased as heart rate was increased. Findings were analyzed separately by parasternal and apical images. Especially in the parasternal images, the scores were significantly increased as heart rate was increased using power motion imaging.Conclusions: We conclude that power motion imaging improves the detection of endocardial border in stress condition with tachycardia, and thus this modality is useful for stress echocardiography.
Effect of left atrial size and function on P‐wave dispersion: A study in patients with paroxysmal atrial fibrillation
Authors: Tüukek Tufan , Akkaya Vakur , Atilgan Dursun , Demirel Şsleref , ÖZCAN Mustafa , Güuven Özen , Korkut Ferruh 
Published: February 2009

AbstractBackground: Paroxysmal atrial fibrillation (PAF), a common arrhythmia, is caused by the fractionated and nonhomo‐geneous propagation of sinus impulse.Hypothesis: This study was undertaken to examine the effect of left atrial (LA) dimension and function on P‐wave dispersion (ΔP) in unselected patients with PAF and healthy controls.Method: In this study, 62 consecutive patients with PAF (32 men, 30 women, mean age 55 ± 11 years) and 62 age‐ and gender‐matched healthy controls (33 men, 29 women, mean age 52 ± 13 years) were studied to compare the effect of LA size, volume, and function on ΔP (difference between maximum and minimum P‐wave duration on 12‐lead electrocardiogram).Results: P‐wave dispersion in patients with PAF and normal LA diastolic diameter (LAD) was longer than that in controls with normal LA size (53 ± 8 vs. 34 ± 8 ms, p < 0.001). P‐wave dispersion increased in patients with PAF (62 ± 12 vs. 53 ± 8 ms, p = 0.003) and controls (40 ± 7 vs. 34 ± 8 ms, p = 0.005) with increased LAD. Presence or absence of PAF did not interact with LAD for their effect on ΔP (2 × 2 analysis of variance test p = 0.20). In the PAF group, ΔP correlated with LAD (r = 0.43, p = 0.002), LA diastolic volume (r = 0.6, p < 0.001), and LA ejection fraction (AEF) (r=‐0.33, p = 0.05). The AEF was preserved when LAD increased in the patients without PAF (0.52 ± 0.07 vs. 0.57 ± 0.10, p = NS), however was significantly decreased in the PAF group (0.37 ±0.12 vs. 0.49 ± 0.10, p = 0.01). On multivariate logistic regression analysis, only δP retained significance on development of PAF.Conclusion: It was concluded that δP increased in patients with PAF and normal LA size. In controls with increased LA size, δP increased but did not reach the levels attained in patients with PAF. The AEF was decreased in patients with PAF but was preserved in those without PAF. These findings can be explained by the changes in LA microarchitecture which concurrently decreased atrial myocardial contraction, increased δP, and predisposed to PAF.