Search PubMed⌕ Search

Biomedical subjects

L A Rhodes

Publications and source records attributed to L A Rhodes.

17 recordsLinked to original sources
PubMed1995

Western bioethics on the Navajo reservation. Benefit or harm?

OBJECTIVE: To understand the Navajo perspective regarding the discussion of negative information and to consider the limitations of dominant Western bioethical perspectives. DESIGN: Focused ethnography. SETTING: Navajo Indian reservation in northeast Arizona. PARTICIPANTS: Thirty-four Navajo informants, including patients, biomedical health care providers, and traditional healers. RESULTS: Informants explained that patients and providers should think and speak in a positive way and avoid thinking or speaking in a negative way; 86% of those questioned considered advance care planning a dangerous violation of traditional Navajo values. These findings are consistent with hózhó, the most important concept in traditional Navajo culture, which combines the concepts of beauty, goodness, order, harmony, and everything that is positive or ideal. CONCLUSIONS: Discussing negative information conflicts with the Navajo concept hózhó and was viewed as potentially harmful by these Navajo informants. Policies complying with the Patient Self-determination Act, which are intended to expose all hospitalized Navajo patients to advance care planning, are ethically troublesome and warrant reevaluation.

Advance Care Planning↗
PubMed1995

Conversion of atrial flutter in pediatric patients by transesophageal atrial pacing: a safe, effective, minimally invasive procedure.

Atrial reentry tachycardia, often termed atrial flutter, is an arrhythmia that is uncommon in the general pediatric population but is seen frequently in patients with congenital heart disease. One goal in treating the arrhythmia is to terminate it, returning the atrium to its underlying rhythm. This report describes the use of transesophageal atrial pacing to attempt termination of atrial reentry in 102 pediatric patients (158 episodes). The patients ranged in age from 1 hour to 41.5 years. Conversion was successful for 112 (71%) of 158 episodes. Six of the 112 episodes required an infusion of procainamide after initial attempts at pacing led to atrial fibrillation. There were no significant differences between the ages of patients or the duration of the tachycardia in comparing successful versus unsuccessful conversions. In contrast, the atrial cycle lengths for the successfully converted tachycardias were significantly greater than for unsuccessful attempts. Transesophageal atrial pacing is a safe and effective means of terminating atrial flutter in the pediatric population. It is minimally invasive, it can often be performed in an outpatient setting, and the technique may occasionally be facilitated by infusion of intravenous procainamide.

Adolescent↗
PubMed1995

Arrhythmias and intracardiac conduction after the arterial switch operation.

UNLABELLED: Intraatrial baffling procedures such as the Mustard or Senning repair of transposition of the great arteries have been associated with a high incidence of cardiac arrhythmias. These abnormalities are thought to arise from trauma to the sinus node and atrial muscle during the procedure. In the arterial switch operation, there is little intraatrial manipulation other than the repair of the atrial septal defect. In theory, rhythm disturbances after the arterial switch operation should be less prevalent. From January 1, 1983, to December 31, 1990, 390 patients (230 with intact ventricular septum and 160 with a coexisting ventricular septal defect) underwent an arterial switch operation. Electrocardiograms and 24-hour Holter monitor studies were obtained in the 364 survivors at hospital discharge and during follow-up. Limited intracardiac electrophysiologic studies were performed 6 to 12 months after the operation. RESULTS: Atrioventricular node function was preserved in most patients; seven patients (2%) had first-degree, two (0.7%) second-degree, and five (1.7%) had complete atrioventricular block (all with coexisting ventricular septal defect). All five patients with complete heart block received a permanent pacemaker. In those patients not having a permanent pacemaker, sinus rhythm was present in 96% on the surface electrocardiogram and 99% during 24-hour Holter monitor studies (1 month to 8.5 years, mean 2.1 years after the operation). Intracardiac electrophysiologic studies (n = 158) demonstrated normal corrected sinus node recovery times and AH intervals in 97% of patients. Atrial ectopy was present in 152 of 172 (81%) patients, with the majority (64%) of patients having only occasional premature beats without repetitive forms. Ventricular ectopy was a frequent finding during 24-hour monitoring. At hospital discharge 70% had ventricular ectopy; these values fell to 57% (in patients with intact ventricular septum) and 30% (in patients with a coexisting ventricular septal defect) at follow-up. In the early postoperative period, there were 25 episodes of supraventricular tachycardia (14 of which required therapy), 6 episodes of junctional ectopic tachycardia, and 9 episodes of ventricular tachycardia. The incidence of supraventricular tachycardia had fallen to 5% at follow-up, with no atrial flutter or fibrillation noted. Three patients had ventricular tachycardia on follow-up Holter studies. In summary, our results confirm the theoretical advantages of anatomic correction over atrial level correction of transposition of the great arteries with respect to preservation of sinus node function and low incidence of clinically significant tachyarrhythmias.

Arrhythmias, Cardiac↗
PubMed1995

Benefits and potential risks of atrial antitachycardia pacing after repair of congenital heart disease.

UNLABELLED: Atrial reentry tachycardia is common after surgical repair of congenital heart disease. The arrhythmia is often difficult to treat and is occasionally life-threatening. This study reports experience with atrial antitachycardia (AAIT mode) pacing for the management of atrial reentry tachycardia, with emphasis on the risks and benefits of automatic pacing therapy. Eighteen patients (2-32 years of age) with a variety of congenital heart lesions underwent atrial antitachycardia pacemaker placement for recurrent atrial tachycardia that was amenable to pace termination prior to the implantation procedure. An appropriate antitachycardia program was determined by repeated induction and termination of atrial tachycardia using the noninvasive programmed stimulation mode of the pacemaker. Over 4-30 months of follow-up, 6 patients had 189 episodes of tachycardia successfully converted with AAI-T pacing, 4 patients had 8 episodes of tachycardia detected but not successfully converted, and 8 patients had no episodes of tachycardia with antibradycardia pacing alone. The number of patients receiving pharmacological therapy other than digoxin or beta blockade fell from 12 to 6. Two subjects died suddenly, 1 while wearing a Holter monitor. In both, tachycardia was detected and pace cardioversion attempted. CONCLUSIONS: Atrial antitachycardia pacing is a useful tool in the management of patients with congenital heart disease and atrial arrhythmias; however, in selected cases, it may not prevent and may even exacerbate the lethal complications of the tachycardia. Antitachycardia function evaluation is recommended under varying levels of autonomic stress prior to institution of automatic therapy.

Adolescent↗
PubMed1994

Programmed atrial stimulation via the esophagus for management of supraventricular arrhythmias in infants and children.

This report describes the use of programmed atrial stimulation via the esophagus to predict the clinical efficacy of various management strategies for supraventricular arrhythmias in infants and children. A total of 203 transesophageal electrophysiologic studies were performed in 132 patients. Therapies evaluated included medications from each antiarrhythmic class, the Valsalva maneuver, follow-up of radiofrequency ablation, and no therapy. The transesophageal technique appeared to be adequate for inducing tachycardia, yielding a low false-negative rate. Overall, the predictive value of a negative study was high (89%), and increased to 96% when stimulation was performed in the presence of isoproterenol. However, the positive predictive value was significantly lower both with (72%, p < 0.00001) and without (60%, p < 0.0001) isoproterenol. These results were due in part to a very low positive predictive value when evaluating either digoxin and/or beta-blocker therapy, 62% vs 82% for the remaining studies. When clinical tachycardia cannot be induced with therapy, transesophageal techniques can be used to predict freedom from many supraventricular tachycardias for most therapies in children. However, induction of tachycardia may not predict treatment failure. Transesophageal pacing to evaluate arrhythmia therapy may be most useful when managing either severe symptoms, multiple recurrences, or the results of radiofrequency ablation.

Anti-Arrhythmia Agents↗
PubMed1994

Differential diagnosis of wide QRS tachycardias.

This article has reviewed the differential diagnosis of wide QRS tachycardia. We have found the stepwise approach suggested by Brugada to be very useful. Of the newer criteria that he proposes, the R to S interval of > 100 ms. appears to be a particularly helpful clue favoring the diagnosis of ventricular tachycardia. Hemodynamic stability, young age, 1:1 AV association, and the absence of structural heart disease do not exclude a diagnosis of ventricular tachycardia. Most wide QRS tachycardias in adults are ventricular, and when all else fails, one will be right more often than not in favoring this as the diagnosis over supraventricular tachycardia with aberrancy. The R to S interval is measured in the precordial (V) leads from the onset of the R wave to the deepest part of the S wave. A value > 100 ms. in any V lead strongly favors ventricular tachycardia. Example is from Case 1 (upper tracing is V1).

Diagnosis, Differential↗
PubMed1993

Catheter ablation of accessory atrioventricular pathways in young patients: use of long vascular sheaths, the transseptal approach and a retrograde left posterior parallel approach.

OBJECTIVES: This study retrospectively assesses the technical aspects of the catheter techniques used to ablate 83 accessory atrioventricular (AV) pathways during 88 procedures in 71 pediatric and adult patients (median age 14 years, range 1 month to 55 years). A number of catheter approaches and techniques evolved that may have improved success and shortened procedure times. BACKGROUND: Radiofrequency catheter ablation of accessory AV pathways can be highly successful. However, the technical difficulty of many of the procedures is masked by the success rate. METHODS: Left free wall, right free wall and septal accessory pathways were ablated with a variety of approaches. RESULTS: Left free wall pathways were ablated successfully by using a standard retrograde approach through the aortic valve in only 10 (24%) of 43 cases. The remaining 33 (76%) required an approach that was either retrograde through the mitral valve (2 of 33), transseptal (21 of 33) or retrograde where the catheter was advanced behind the posterior mitral leaflet at the point of mitral-aortic continuity, so that the catheter course was parallel rather than perpendicular to the mitral anulus (10 of 33). Nineteen of 20 septal pathways were ablated successfully by using either the parallel approach (2 of 29), a transseptal approach (2 of 19), ablation within the coronary sinus or one of its veins (8 of 19) or ablation on the atrial side of the tricuspid valve (7 of 19). Fifteen of 20 right free wall pathways were ablated successfully with a variety of approaches on both the atrial and the ventricular side of the tricuspid valve. Long vascular sheaths were judged to contribute directly to success in 33 (43%) of 77 pathways. The overall success rate has been 93% (77 of 83 pathways), with 100% success for left free wall (43 of 43), 75% for right free wall (15 of 20) and 95% for septal pathways (19 of 20). CONCLUSIONS: Thus, successful ablation of accessory AV pathways in a mixed group of pediatric and adult patients appears to benefit from a wide range of vascular and catheter approaches.

Adolescent↗
PubMed1993

Ethnography.

Explore the source record for details and available documents.

Ethnology↗
PubMed1993

Update on therapy for atrial fibrillation.

This article reviews newer trends in the management of patients with atrial fibrillation. The roles of chronic antiarrhythmic therapy, anticoagulation, and nonpharmacologic treatments are discussed.

Anti-Arrhythmia Agents↗
PubMed1992

Transcatheter ablation of ectopic atrial tachycardia in young patients using radiofrequency current.

BACKGROUND: Ectopic atrial tachycardia (EAT) is a reversible cause of cardiomyopathy but may be quite difficult to control with conventional therapy. Transcatheter ablation with radiofrequency current was tested as an alternative to medical or surgical treatment of this condition. METHODS AND RESULTS: Twelve young patients (aged 10 months to 19 years) with drug-resistant EAT were treated with direct transcatheter ablation of the ectopic focus using radiofrequency (RF) energy. All had depressed left ventricular contractility by echocardiographic criteria, involving shortening fractions of 10-26% (median, 20%; normal, 28-35%). The EAT was mapped to the left atrium in seven cases and to the right atrium in five. Local atrial activation at the ectopic site preceded the onset of the surface P wave by 20-60 msec (median, 42 msec). Tachycardia terminated 0.5-13.0 seconds (median, 2.0 seconds) into a successful RF application. The ablation effectively eliminated EAT in 11 of 12 patients (92%), all of whom were discharged in sinus rhythm without medications after a median hospital stay of 48 hours. Ablation was unsuccessful in one patient with diffuse dysplasia of the anterior right atrium, who eventually did well after surgical resection of abnormal atrial tissue. Transient depression of sinus node function was noted in one patient who had successful ablation of an EAT focus in close proximity to the sinus node, although normal sinus node function returned within 72 hours. No other complications were encountered. During follow-up (3-21 months; median, 13 months), one patient had recurrence of a slower and less-sustained EAT that was successfully eliminated at a second ablation session. All others remained in sinus rhythm, and all 12 subjects recovered normal ventricular function. CONCLUSIONS: RF ablation appears to be a safe and effective therapeutic option for drug-resistant ectopic atrial tachycardia and may be the preferred first-line therapy for those patients with depressed ventricular function.

Adolescent↗
PubMed1992

Radiofrequency catheter ablation of cardiac arrhythmias: initial WVU experience.

Radiofrequency catheter ablation is a method of selectively destroying cardiac tissue to treat various arrhythmias. In a relatively short time, it has evolved from an investigational tool to a widely applied clinical technique (1). This article reviews the current status of radiofrequency catheter ablation and reports on the results of its initial clinical use in 14 patients at West Virginia University Hospital.

Aged↗
PubMed1991

Predictors of survival in neonates with critical aortic stenosis.

BACKGROUND: Failure of infants with critical aortic stenosis to survive after adequate valvotomy despite a left ventricular size that appears to be adequate indicates that additional preoperative anatomic features may contribute to mortality. METHODS AND RESULTS: Discriminant analysis was used to determine which of several echocardiographically measured left heart structures were independent predictors of survival after valvotomy for neonatal critical aortic stenosis. It was possible to predict outcome after classic valvotomy (two-ventricle-type repair) with 95% accuracy based on mitral valve area, long-axis dimension of the left ventricle relative to the long-axis dimension of the heart, diameter of the aortic root, and body surface area. Left ventricular volume was not a major determinant in this study, in part because patients who had initial valvotomy had been preselected in favor of an adequately sized left ventricle. Patients with multiple small left ventricular structures were found to have significantly improved survival after initial Norwood operation. In contrast, balloon valvotomy with subsequent Norwood procedure was usually unsuccessful. CONCLUSIONS: The adverse effects of small inflow, outflow, and/or cavity size of the left ventricle are cumulative. The accuracy of prediction of outcome based only on preoperative anatomy indicates that adequacy of valvotomy is not generally a limiting factor for survival in this group of patients. It is possible to identify subjects whose chance of survival is better after a Norwood procedure rather than valvotomy, even if left ventricular volume is not critically small.

Aortic Valve Stenosis↗
PubMed1990

Long follow-up (to 43 years) of ventricular septal defect with audible aortic regurgitation.

From 1946 to March 1989, 92 patients (33 women and 59 men) were seen with ventricular septal defect (VSD) and audible aortic regurgitation (AR). The VSD was subcristal in 62 patients, subpulmonary in 21 and unknown in the remaining 9. The median age of onset of AR was 5.3 years. The risk of developing AR was 2.5 times greater in those with a subpulmonary VSD. The aortic valve was tricuspid in 90% and bicuspid in 10%. Prolapse was seen in 90% of those with subcristal VSD and in all with subpulmonary VSD. Pulmonary stenosis was seen in 46% of the patients with gradients ranging from 10 to 55 mm Hg. The incidence of infective endocarditis was 15 episodes/1,000 patient years. Among 20 patients followed medically, for 297 patient years, 1 died (1959) and most have been stable, including 2 followed for greater than 30 years. In the 72 patients operated on, there were 15 perioperative and 5 late deaths. Operations consisted of VSD closure alone in 7, VSD closure and valvuloplasty in 50 and VSD closure and aortic valve replacement in the other 15. Valvuloplasty was more effective in those operated on under age 10 compared to those older than 15 years (46 vs 14%). The durability of the valvuloplasty was 76% at 12 years and 51% at 18 years.

Actuarial Analysis↗
PubMed1984

"This will clear your mind": the use of metaphors for medication in psychiatric settings.

Psychiatric medications are an important part of the interaction between patients and clinicians in psychiatric settings. This article examines metaphors used by patients and clinicians to talk about the effects of antipsychotic medication. Metaphors provide a way to communicate about issues of identity and change involved in giving and taking medication. Although metaphorical language can contribute to misunderstandings between patients and clinicians, metaphor is also a major way in which clinical experiences are given shared meanings.

Adult↗