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PubMed2005

Acceptability of a computerized alcohol screening and advice routine in an emergency department setting--a patient perspective.

Disseminating screening and brief alcohol intervention in routine emergency department (ED) care seems to be a demanding challenge due to the complexity of the emergency setting. Further empirical realistic intervention models need to be developed that are appropriate for staff and patients before such models are tested in large scale controlled trials. This study explores patients' acceptance of a computerized opportunistic alcohol screening, followed by a personalized printout as feedback, at an emergency department performed by ordinary emergency department staff. In all, 44 patients were interviewed after performing the computerized screening test. The majority of patients were positive about answering the questions about alcohol habits, and 95% found it easy to use the touch screen and understand the instructions, even those with little computer experience. Regarding the personalized printout of advice, 76% were positive to this kind of feedback and 93% said they would read the printout. Most patients, 74%, preferred the computerized printout instead of a more personalized feedback from staff members. Whether the computerized advice is sufficient for a change in alcohol habits among excessive drinkers is still to be shown in controlled trials, but the concept could be one means of making preventive measures more feasible in a real-world ED setting. This might provide a basis for dissemination and integration of more extensive interventions in the long term.

Alcohol Drinking↗

PubMed2006

The Internet Tracking Registry of Acute Coronary Syndromes (i*trACS): a multicenter registry of patients with suspicion of acute coronary syndromes reported using the standardized reporting guidelines for emergency department chest pain studies.

STUDY OBJECTIVE: Observational studies of well-described patient populations presenting to emergency departments (EDs) with suspicion of acute coronary syndrome are necessary to understand the relationships between patients' signs and symptoms, cardiac risk profile, test results, practice patterns, and outcomes. We describe the methods for data collection and the ED population enrolled in a multicenter registry of patients with chest pain. METHODS: Patients older than 18 years, presenting to one of 8 EDs in the United States or 1 ED in Singapore, and with possible acute coronary syndrome were enrolled in the Internet Tracking Registry of Acute Coronary Syndromes between June 1999 and August 2001. Prospective data, including presenting signs and symptoms, ECG findings, and the ED physician's initial impression of risk, were systematically collected. Medical record review or daily follow-up was used to obtain cardiac biomarker results, invasive and noninvasive testing, treatments, procedures, and inhospital outcomes. Thirty-day outcomes were determined by telephone follow-up and medical record review. RESULTS: The registry includes 15,608 patients, with 17,713 visits. Chest pain was the chief complaint in 71% of visits. The ECG was diagnostic of ischemia or infarction in 10.1% and positive cardiac biomarkers were observed in 10% of visits. Forty-three percent of patients were sent home directly from the ED. Of admitted patients, 5% died by 30 days, and 3% had documented coronary artery disease or had undergone percutaneous coronary intervention or coronary artery bypass grafting within 30 days. For patients discharged directly from the ED, 0.4% died or had a documented myocardial infarction within 30 days. Coronary artery bypass graft surgery, percutaneous coronary intervention, or a diagnosis of coronary artery disease was found in 0.5% of discharged patients. CONCLUSION: A unique description of undifferentiated ED chest pain patients with suspected acute coronary syndrome is provided. The data set can be used to generate and explore hypotheses to improve understanding of the complex relationships between presentation, treatment, testing, intervention and outcomes.

Biomarkers↗

PubMed2002

Adherence to antiretroviral therapy among patients with HIV: a critical link between behavioral and biomedical sciences.

Rapid advances in biomedical science, such as pharmaceutical developments for HIV disease, must be integrated with advances in behavioral science to further our understanding of medication adherence. This article evaluates the current state of the science in adherence to antiretroviral therapy for persons with HIV. The primary objectives are to 1) identify critical determinants of adherence, and 2) describe interventions to improve adherence. Adherence is a complex dynamic behavior influenced by characteristics of the patient, treatment regimen, disease, patient-provider relationship, and clinical setting. Therefore, the most promising interventions are multifaceted and target different locations in this matrix simultaneously. Unfortunately, nonadherence remains a formidable barrier in the management of HIV, resulting in the development of resistance and drug failure. Moreover, adherence is a public health concern, with implications for the transmission of HIV in general and the transmission of drug-resistant strains of HIV specifically. Despite substantial attention to adherence in recent years, much more remains to be done to better understand and promote adherence to antiretroviral therapy through effective interventions. From this integration of biomedical and behavioral science, effective clinical interventions can be developed and implemented to enhance the health of patients with HIV.

Antiretroviral Therapy, Highly Active↗

PubMed2001

How to help depressed older people living in residential care: a multifaceted shared-care intervention for late-life depression.

OBJECTIVE: To describe a population-based, multifaceted shared-care intervention for late-life depression in residential care as a new model of geriatric practice, to outline its development and implementation, and to describe the lessons learned during the implementation process. SETTING: A large continuing-care retirement community in Sydney, Australia, providing three levels of care (independent living units, assisted-living complexes, and nursing homes). PARTICIPANTS: The intervention was implemented for the entire non-nursing home population (residents in independent and assisted living: N = 1,466) of the facility and their health care providers. Of the 1,036 residents whowere eligible and agreed to be interviewed, 281 (27.1%) were classified as depressed according to the Geriatric Depression Scale. INTERVENTION DESCRIPTION: The intervention included: (a) multidisciplinary collaboration between primary care physicians, facility health care providers, and the local psychogeriatric service; (b) training for primary care physicians and other facility health care providers about detecting and managing depression; and (c) depression-related health education/promotion programs for residents. CONCLUSIONS: The intervention was widely accepted by residents and their health care providers, and was sustained and enhanced by the facility after the completion of the study. It is possible to implement and sustain a multifaceted shared-care intervention for late-life depression in a residential care facility where local psychogeriatric services are scarce, staff-to-resident ratios are low, and the needs of depressed residents are substantial.

Aged↗

PubMed2004

Effect of feeding malnourished patients for 1 mo on mitochondrial complex I activity and nutritional assessment measurements.

BACKGROUND: We showed previously that the activity of complex I (the first enzyme of the electron transport chain) in peripheral blood mononuclear cells decreases with malnutrition and increases to a subnormal value after 1 wk of refeeding, but the traditional markers of nutritional status do not do so. OBJECTIVE: The aim of this study was to ascertain whether a period of nutritional intervention longer than 1 wk would normalize complex I activity and traditional markers of nutritional status. DESIGN: Fifteen malnourished patients (7 women and 8 men) with > or =10% body weight loss over the previous 6 mo were studied on the day of their admission to hospital and 7, 14 and 30 d after the beginning of nutritional support. Complex I activity in peripheral blood mononuclear cells, weight, height, body composition, body water compartments, dietary intake, and serum albumin concentrations were measured on each occasion. The results before and during nutritional intervention were compared with values obtained in 30 healthy volunteers (17 women and 13 men). RESULTS: Complex I activity increased significantly after the first week of refeeding (P < 0.001) and reached a normal value after 1 mo of nutritional supplementation. Among the classic markers of nutritional status, only the ratio of extracellular water to intracellular water tended to decrease over the refeeding period. CONCLUSION: Complex I activity increases rapidly and is normalized by refeeding at a time when other markers of nutritional status do not change significantly.

Adult↗

PubMed2026

Causal Relationship of Polyunsaturated Fatty Acids With Mental Disorders: A Systematic Review and Meta-analysis.

CONTEXT: Mental disorders (MDs) pose a important global health challenge, with a complex pathogenesis complicating treatment development. Nutritional interventions, particularly polyunsaturated fatty acids (PUFAs), have gained attention as potential therapeutic options. OBJECTIVE: This Mendelian randomization (MR) meta-analysis aimed to evaluate the potential causal relationship between PUFAs and MDs. DATA SOURCES: Genome-wide association study data were utilized to analyze the association between PUFAs (including omega-3, omega-3 percentage [omega-3%], omega-6, omega-6 percentage [omega-6%], and omega-6 to omega-3 ratio) and 12 major MDs. DATA EXTRACTION: Two-sample MR technology was used to assess the role of PUFAs in MDs. DATA ANALYSIS: The MR analysis revealed that genetically predicted omega-3 was causally linked to MDs, such as obsessive-compulsive disorder, bipolar disorder, schizophrenia, and major depressive disorder. Omega-3% exhibited protective effects against emotional personality disorder. Conversely, omega-6 was inversely correlated with attention-deficit/hyperactivity disorder risk, while a high omega-6 to omega-3 ratio was associated with an increased risk of depression and other mood disorders. CONCLUSION: High omega-3 levels and omega-3% may reduce the risk of MDs, whereas a high omega-6:omega-3 ratio may elevate the risk. These findings highlight the potential of PUFAs, particularly omega-3, in MD prevention and treatment, while underscoring the need for further research into the complex interactions between omega-3 and omega-6. The study provides a scientific foundation for future clinical trials and dietary intervention strategies. SYSTEMATIC REVIEW REGISTRATION: PROSPERO no. CRD42024598472.

Humans↗

PubMed2002

How many patients with haematological malignancy need the facilities offered by a district general hospital?

BACKGROUND: The objective of the study was to study the utilization of specialist clinical services for haematological malignancy in a defined patient population. Patients with haematological malignancy are mostly aged over 65 years. Demographic projections for the United Kingdom suggest that the incidence of haematological malignancy will increase by 20 per cent in the next 20 years, mostly as a result of demographic change. METHODS: A prevalence survey was carried out of out-patients with haematological malignancy resident in the New Forest area and their utilization of haematology clinical services at two sites. RESULTS: One hundred and ten patients (60 male, 50 female) were identified over three months: 87 (79 per cent) were aged over 65 years. Follow-up and therapy were carried out at a community hospital at Lymington, 19 miles from Southampton, in 83 patients (79 per cent, 45 male, 38 female, median age 74.9 years), and at one of two large hospitals in Southampton in 27 patients (21 per cent, 15 male, 12 female, median age 73.8 years). Attendance for more complex treatment at Southampton was necessary for 10 patients (9 per cent) in the Lymington group. Most interventions in both groups (356/379; 94 per cent) were basic, and were available and undertaken at either study site. Only 23/379 (6 per cent) of interventions required by the patient sample were more complex. CONCLUSIONS: Most haematological malignancies are chronic disorders with a simple clinical management plan, requiring periodic clinical monitoring. A consultant-led haematology clinic supported by access to multipurpose day treatment facilities in the community hospital allowed 75 per cent of patients to receive their care at a more geographically convenient location, important for conditions in which 79 per cent of patients are aged over 65 years, and in which this proportion will increase. Only a minority of cases require care in specialist hospital haematology units; the majority can be managed using community-based haematological follow-up care. Future studies are needed to assess cost-effectiveness and the impact on primary care of increasing the use of community-based treatment facilities.

Aged↗

PubMed2001

[Surgical treatment of coarctation and interrupted aortic arch complex in infants].

One hundred forty-two consecutive neonates or early infants with coarctation and interrupted aortic arch complex who underwent biventricular repair at the Fukuoka Children's Hospital between January 1991 and December 2000 were reviewed. One-stage repair was performed in 33 patients (35%) with coarctation complex and in 41 patients (85%) with interrupted aortic arch complex. The overall mortality rate was 6.1% in one-stage repair and 6.6% in two-stage repair of coarctation complex patients and 9.8% in one-stage repair and 28.6% in two-stage repair of interrupted aortic arch complex patients. The recoarctation rate was 5.3% in coarctation complex and 2.1% in interrupted aortic arch complex. All patients with recoarctation underwent successful catheter intervention and required no reoperation. In conclusion, one-stage repair of interrupted aortic arch and coarctation complex with the anterior approach resulted in good outcomes. Then descending aorta cannulation through a median sternotomy combined with the cerebral perfusion technique enables complete avoidance of circulatory arrest and is a useful technique. However, a two-stage procedure can be useful in the patients whose condition has deteriorated substantially or in whom intracardiac anomalies are severe.

Aorta, Thoracic↗

PubMed1990

Addiction in adolescents.

Some symptoms seen in adolescents with the disease of chemical dependence are similar to those seen in adults. Because of their age, lack of personality development, dependent family role, immaturity, and acting out of age-related behavioral tendencies, however, symptoms specific to this population occur. These may become exacerbated and telescope--intensify and shorten--the progression of the disease. A plan to solve the problem of adolescent chemical dependence must focus on education, demonstration, cooperation, prevention, intervention, habilitation, treatment, and recovery. The phenomenon of denial in a chemically dependent adolescent yields a more complex delusional system that dictates age-specific intervention approaches. Habilitation is necessary for successful adolescent treatment and recovery because what is needed is an initial process of learning, not relearning or rehabilitation. If specific adolescent issues are addressed through comprehensive, multimodality treatment approaches, then treatment and recovery outcomes for chemically dependent adolescents and their families are substantially improved. Primary care physicians must be alert to the possibility of drug use in their young patients and aware of treatment options.

Adolescent↗

PubMed2001

Patient adherence to treatment: three decades of research. A comprehensive review.

Low compliance to prescribed medical interventions is an ever present and complex problem, especially for patients with a chronic illness. With increasing numbers of medications shown to do more good than harm when taken as prescibed, low compliance is a major problem in health care. Relevant studies were retrieved through comprehensive searches of different database systems to enable a thorough assessment of the major issues in compliance to prescribed medical interventions. The term compliance is the main term used in this review because the majority of papers reviewed used this term. Three decades have passed since the first workshop on compliance research. It is timely to pause and to reflect on the accumulated knowledge. The enormous amount of quantitative research undertaken is of variable methodological quality, with no gold standard for the measurement of compliance and it is often not clear which type of non-compliance is being studied. Many authors do not even feel the need to define adherence. Often absent in the research on compliance is the patient, although the concordance model points at the importance of the patient's agreement and harmony in the doctor-patient relationship. The backbone of the concordance model is the patient as a decision maker and a cornerstone is professional empathy. Recently, some qualitative research has identified important issues such as the quality of the doctor-patient relationship and patient health beliefs in this context. Because non-compliance remains a major health problem, more high quality studies are needed to assess these aspects and systematic reviews/meta-analyses are required to study the effects of compliance in enhancing the effects of interventions.

Attitude to Health↗

PubMed2001

The molecular genetics of bone formation: implications for therapeutic interventions in bone disorders.

Skeletal biology is a complex process involving the developmental commitment and differentiation of chondrocytes and osteoblasts which produce and mineralize cartilage and bone matrix during growth and postnatal life. Several genes are involved in controlling osteogenesis by acting on target cells in a very complex manner. Manipulation of genes in mice and studies of genetic mutations affecting the skeleton in humans have enabled the assessment of the role of transcription factors, bone matrix proteins and regulatory factors involved in the control of chondrocyte and osteoblast differentiation, and have considerably improved our understanding of the bone formation process. Clinical studies and gene polymorphism analyses suggest that the variable expression of particular genes may be linked to clinical osteoporosis. A major challenge in the future will be to develop molecularly targeted approaches to stimulating bone formation and increasing bone mass. The use of mouse strain models and transgenic animals with variable bone density may be useful to identify genetic determinants of bone mass which may serve as a basis for drug discovery and development. On the other hand, the availability of gene microarrays and other emerging genomic techniques are promising tools to identify genes that are distinctly expressed in health and disease. These technologies may also serve to test the mechanisms of action of drugs aimed at increasing bone formation. Genetic studies of the molecular signaling pathways involved in normal and pathological osteogenesis may also help to identify genes that could be targeted for therapeutic intervention. Candidate approaches include selective gene transfection in target cells and the use of drugs acting on gene promoters to selectively enhance gene expression in osteoblasts. The development of these strategies is expected not only to bring new insight into the molecular mechanisms that govern bone formation in normal and pathological situations but, in the long term, may also result in the identification of novel molecular targets for therapeutic interventions for bone formation disorders.

Bone Development↗

PubMed2005

Anesthetic management and outcome of complex late arterial-switch operations for patients with transposition of the great arteries and a systemic right ventricle.

OBJECTIVE: For patients with transposition of the great arteries and a systemic right ventricle, complex late arterial-switch operations (double switch, switch conversion, Senning-Rastelli) after the newborn period have been described recently to restore the morphologic left ventricle to the systemic circulation. The purpose of this study was to describe the anesthetic management and perioperative outcome of this group of patients and to compare them with a control group of patients who had primary arterial-switch operations in the neonatal period. DESIGN: Retrospective database and medical record review with 3:1 control:case ratio. SETTING: Tertiary care academic children's hospital. PARTICIPANTS: Patients undergoing complex late-arterial switch operations after the newborn period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Thirteen patients were identified in the complex late-switch group and 43 in neonatal arterial-switch group. There were no perioperative deaths, no new gross neurologic deficits, and all patients were discharged home in both groups. Anesthetic and bypass times were significantly longer in the late-switch group (745 v 558 minutes, p < 0.001, and 382 v 243 minutes, p < 0.001, respectively). Transfusion requirements were similar between the groups. The incidence of arrhythmia (92% v 9%, p < 0.001), use of pacing systems (69% v 9%, p < 0.001), cardioversion (15% v 0%, p = 0.05), and pharmacologic treatment of arrhythmias (69% v 0%, p < 0.01) intraoperatively were significantly higher in the complex late-switch group. CONCLUSIONS: Patients presenting for complex late corrective operations for transposition of the great arteries require long and complex anesthetics. Despite these challenges, perioperative outcomes are excellent.

Adolescent↗

PubMed2006

Improvements in insulin resistance with weight loss, in contrast to rosiglitazone, are not associated with changes in plasma adiponectin or adiponectin multimeric complexes.

It has been suggested that changes in adiponectin levels may contribute to improved insulin sensitivity in insulin-resistant individuals both after weight loss and after treatment with thiazolidinedione compounds. If this is correct, then changes in total circulating adiponectin and/or distribution of its multimeric complexes should coincide with improvements in insulin sensitivity after both interventions. To address this issue, fasting adiponectin concentrations and distribution of adiponectin complexes were measured in plasma samples in 24 insulin-resistant, nondiabetic subjects before and after 3-4 mo of treatment with either rosiglitazone or caloric restriction. The degree of insulin resistance in each group of 12 subjects was equal at baseline and improved to a similar extent ( approximately 30%) after each therapy. Whereas total adiponectin levels increased by nearly threefold and the relative amount of several higher molecular weight adiponectin complexes increased significantly in the rosiglitazone treatment group, there were no discernible changes in adiponectin levels or in the distribution between high or low molecular weight complexes in the weight loss group. These data indicate that, although changes in total adiponectin and several specific adiponectin complexes paralleled improvements in insulin resistance in thiazolidinedione-treated subjects, neither circulating adiponectin concentrations nor multimeric complexes changed in association with enhanced insulin sensitivity after moderate weight loss in 12 insulin-resistant, obese individuals.

Adiponectin↗

PubMed1998

Population-based public health nursing interventions: a model from practice.

In a changing and complex health care system, public health nurses face challenges to explain their work and contributions to health outcomes. In response to this need, the Minnesota Department of Health, Section of Public Health Nursing, initiated a process to describe public health nursing interventions. The Public Health Nursing Interventions (PHI) Model was developed through a collaborative process by public health nurses at the state and local levels. The purpose of the model was to define more clearly the practice of public health nursing and to describe better the work of public health nurses at the community and systems levels. The PHI model identifies 17 interventions and provides practice examples at the systems, community and individual/family levels. The model defines a broader view of the mission and scope of public health nursing. Practice examples are given for agency staff, administrators, educators, and policy makers.

Community Health Planning↗

PubMed1992

Immunologic mechanisms of transplant rejection.

This article reviews recent progress in understanding the mechanisms of organ transplant rejection and focuses on studies that suggest new approaches to diagnosis and treatment. The alloimmune response is initiated by recognition of donor major histocompatibility complex antigens by the immune system of the host. During rejection, the upregulation of major histocompatibility complex antigens on donor tissue enhances this recognition phase. Rejection can be prevented by interfering with the interaction of recipient T cells with alloantigens using interventions such as antibodies against major histocompatibility complex proteins or accessory adhesion molecules, peptide-binding antagonists, and genetic alteration of major histocompatibility complex protein expression. Patterns of cytokines produced in the graft following transplantation may be used to distinguish rejection from other causes of transplant dysfunction. In addition, specific antagonists of individual cytokines show promise as antirejection treatments.

Graft Rejection↗

PubMed1997

Proinflammatory cytokine release during pediatric cardiopulmonary bypass: influence of centrifugal and roller pumps.

OBJECTIVE: It has been proposed that nonocclusive centrifugal pumps may elicit less blood cell trauma and hence a reduced inflammatory response than standard roller pumps. However, there have been no reports describing the impact of such pumps on proinflammatory cytokine release in pediatric cohorts. DESIGN: A prospective randomized study was undertaken. SETTING: A regional cardiothoracic center of a university hospital. PARTICIPANTS: Thirty-four pediatric patients undergoing cardiopulmonary bypass (CPB) for the correction of complex congenital heart defects were recruited. INTERVENTIONS: Either standard twin roller (n = 17), or centrifugal vortex (Biopump, Medtronic Biomedicus Inc, MN) (n = 17) blood pumping. MEASUREMENTS AND MAIN RESULTS: Venous blood was drawn (1) on induction of anesthesia, (2) 5 minutes on bypass, (3) end of CPB, (4) 30 minutes post-protamine, (5) 2 hours and (6) 24 hours postoperation. Neutrophil count, level of plasma leukocyte elastase, terminal complement complex (C5b-9); interleukin-6 (IL-6) and interleukin-8 (IL-8) were increased during and after CPB compared with the postinduction baseline. C5b-9 levels in both groups peaked at the end of CPB before returning to baseline at 24 hours: (median [range]), 564 (16 to 1,136) ng/mL in centrifugal group versus 508 (0 to 1,128) ng/mL in the roller group. IL-6 in both groups reached its peak level at 2 hours postprotamine (208 [98 to 411] pg/mL in centrifugal versus 205 [60-327] pg/mL in the roller group), before coming back to baseline at 24 hours. Plasma leukocyte elastase and IL-8 reached their maximum level 15 minutes after protamine administration: 215 (64 to 375) pg/mL in centrifugal versus 235 (87 to 410) pg/mL in roller group; and 700 (90 to 5,925) ng/mL versus 362 (120 to 3,400) ng/mL, respectively. CONCLUSIONS: The current study confirms the proinflammatory nature of pediatric CPB surgery, but failed to show a significant advantage of centrifugal pumping over roller perfusion in terms of the inflammatory response.

Cardiopulmonary Bypass↗

PubMed1996

[Transmyocardial laser revascularization--limits and possibilities].

Indications for interventional catheter techniques and bypass surgery have been extended to more complex lesions and also the number of reoperations after primary successful interventions has increased due to progression of the underlying disease. Finally a number of patients remains still symptomatic but, as a consequence of a very diffuse distribution of atherosclerotic lesions, is no longer accessible with conventional techniques of direct revascularization. This has drawn the attention again to indirect techniques of myocardial revascularization. Transmyocardial laserrevascularization offers a new option in reperfusing the ischemic myocardium via transmural channels from the ventricular cavity. As to the function of the channels, it is not quiet clear, wether they may connect to intramyocardial capillaries or may themselves induce a neoangiogenesis. However the clinical follow up in patients with intractable angina pectoris shows a significant improvement. At our hospital a number of 117 patients have been treated with this new method, 53 of them in conjunction with conventional bypass surgery. Clinical follow up after three and six months postoperatively showed a significant improvement concerning angina (CCS) and exercise tolerance (NYHA). This could also objectively be demonstrated by scintigraphy with an increased myocardial perfusion in 50% of the reinvestigated patients. Ischemic areas can still be seen, but occur at a significantly higher exercise level, demonstrating an improved but not normalized myocardial blood supply. The transmyocardial laserrevascularization is no alternative to well established procedures like PTCA or bypass surgery, but can be seen as a therapeutic option for those symptomatic patients recently being intractable. Further longterm studies and also experimental investigations have to evaluate the definitive role of this new treatment for endstage coronary heart disease.

Adult↗

PubMed2004

Conduction system abnormalities in patients with obstructive hypertrophic cardiomyopathy following septal reduction interventions.

We observed the impact of percutaneous transluminal septal myocardial ablation (PTSMA) and myectomy on the conduction system in patients with obstructive hypertrophic cardiomyopathy (HC). Septal reduction intervention is capable of eliminating the left ventricular outflow tract obstruction in patients with obstructive HC; however, conduction system abnormalities are frequent consequences of these procedures. A standard 12-lead electrocardiogram and Doppler echocardiogram were obtained in 204 patients who underwent PTSMA (n = 70) or myectomy (n = 134) before and at average of 3 months after intervention. Of 146 patients who had normal conduction systems before intervention, the duration of the QRS complex was significantly prolonged from 98 +/- 15 to 130 +/- 25 ms (p <0.0001), with right bundle branch block (RBBB) developing in 62% patients after PTSMA, and from 100 +/- 13 to 154 +/- 20 ms (p <0.0001), with left bundle branch block (LBBB) developing in 93% patients after myectomy. No significant difference in the QRS duration was found in the remaining 58 patients who had preexisting conduction abnormalities after intervention. In 174 patients without a preexisting permanent pacemaker, a pacemaker was implanted in 22% versus 13% of patients who underwent PTSMA (overall and without preexisting conduction block, respectively) and 10% versus 2% of patients with myectomy. The duration of baseline QRS was an independent predictor for the requirement of a permanent pacemaker (p <0.0001). Thus, RBBB often develops after PTSMA and LBBB is very frequently produced by myectomy. A possible requirement of a permanent pacemaker should always be considered before intervention when patients have preexisting RBBB or LBBB.

Bundle-Branch Block↗