Cardiac release of histamine after ventricular fibrillation and defibrillation during insertion of implantable cardioverter defibrillators (ICD)

Histamine has inotropic, chronotropic, arrhythmogenic, and vasoactive effects, and is released from the heart in ischaemia-reperfusion injury. The effect of ventricular fibrillation (VF) and defibrillation (DEF) on histamine release was investigated in 9 anaesthetized patients undergoing transvenous implantation of ICD. Concomitant arterial and coronary sinus (CS) blood samples were drawn before induction of VF (duration 20 seconds), immediately after, and 2 and 5min after DEF (18–24 Joules). Basal arterial histamine was 2.5±6nmol/1, and did not increase after VF. The histamine level in CS was 1.1±0.2nmol/1 before VF (p < 0.008 compared to arterial), and increased to 2.5 ± 0.6 nmol/1 immediately after (p < 0.045 compared to basal), to 3 ± 1.1 nmol/1 2 min after (p < 0.45), and to 2.4 ± 0.8 nmol/1 5min after VF. In the basal state there was an uptake of histamine across the coronary circulation. After VF/DEF the level of histamine increased in coronary venous blood, suggesting cardiac release of histamine.     

Predictors of quality of life in patients with implantable cardioverter defibrillators

Few studies have prospectively examined characteristics of implantable cardioverter defibrillator (ICD) patients as predictors of postimplant outcome. In this study the authors considered the association between preimplant psychological characteristics, ICD shocks, and postimplant quality of life at short- and long-term follow-ups, controlling for age and ejection fraction (N=88). Hierarchical regression analyses revealed that history of depression, trait anxiety, optimism, social support, and ICD shocks accounted for 41.8% to 64.5% of the variance in quality of life indices at 8- and 14-month follow-ups, depending on the outcome assessed. Further, psychological variables were as strong as, or stronger than, age, ejection fraction, and ICD shocks in predicting quality of life outcomes.     

Ventricular arrhythmias and changes in heart rate preceding ventricular tachycardia in patients with an implantable cardioverter defibrillator

The objective was to determine the characteristics of heart rate variability and ventricular arrhythmias prior to the onset of ventricular tachycardia (VT) in patients with an implantable cardioverter defibrillator (ICD). Sixty-eight beat-to-beat time series from 13 patients with an ICD were analyzed to quantify heart rate variability and ventricular arrhythmias. The episodes of VT were classified in one of two groups depending on whether the sinus rate in the 1 min preceding the VT was greater or less than 90 beats per minute. In a subset of patients, increased heart rate and reduced heart rate variability was often observed up to 20 min prior to the VT. There was a non-significant trend to higher incidence of premature ventricular complexes (PVCs) before VT compared to control recordings. The patterns of the ventricular arrhythmias were highly heterogeneous among different patients and even within the same patient. Analysis of the changes of heart rate and heart rate variability may have predictive value about the onset of VT in selected patients. The patterns of ventricular arrhythmia could not be used to predict onset of VT in this group of patients.     

The distressed (Type D) personality in both patients and partners enhances the risk of emotional distress in patients with an implantable cardioverter defibrillator

BackgroundA subgroup of patients with an implantable cardioverter defibrillator (ICD) experiences emotional distress. This may be related to partner factors. We examined the impact of the personality of the partner (i.e., the distressed (Type D) personality) in combination with that of the patient on anxiety and depression levels in ICD patients.MethodsConsecutively implanted ICD patients (N = 281; 80.1% men; mean age = 58.3 ± 11.0) and their partners (N = 281; 20.6% men; mean age = 56.5 ± 11.7) completed the Type D Scale at baseline; patients also completed the Hospital Anxiety and Depression Scale at baseline and 6 months post-implantation.ResultsANOVA for repeated measures, using the Type D main effects and the interaction effect, showed that the interaction time by Type D patient by Type D partner was significant (F_(1,277)=7.0, p = .009) for depression as outcome, but not for anxiety (F_(1,277) = 3.1, p = .08). Post-hoc comparisons revealed that Type D patients with a Type D partner (n = 23/281, 8.2%) experienced the highest depression levels compared to other personality combinations (all ps < .05).LimitationsThe group of Type D patients with a Type D partner was rather small.ConclusionsICD patients with a Type D personality report more depressive symptoms, but not anxiety, if the partner also has a Type D personality. This may be due to poor communication and lack of emotional support in the relationship. These results emphasize the importance of taking into account the psychological profile of the partner in the management and care of the ICD patient, and to direct behavioural support not only at the ICD patient but also at the partner.     

Classic conditioning and dysfunctional cognitions in patients with panic disorder and agoraphobia treated with an implantable cardioverter/defibrillator

OBJECTIVE: A model for the development of anxiety disorders (panic disorder with or without agoraphobia) is needed. Patients with an implantable cardioverter/defibrillator (ICD) are exposed to repeated electric shocks. If the theory of anxiety development by aversive classic conditioning processes is valid, these repeated shocks should lead to an increased risk of anxiety disorders. To study this hypothesis, we retrospectively studied 72 patients after implantation of an automatic ICD. METHODS: Patients were assessed with the semistructured Diagnostic Interview of Psychiatric Disease 1 to 6 years after implantation of an automatic ICD. Panic disorder and/or agoraphobia was diagnosed in patients who fulfilled all DSM-III-R criteria for those conditions. RESULTS: Anxiety disorder developed in 15.9% of patients after ICD implantation. This was significantly related to the frequency of repeated defibrillation (shocks) to stop malignant ventricular arrhythmias. Dysfunctional cognitions are an additional vulnerability factor. CONCLUSIONS: The data support both the conditioning hypothesis and the cognitive model of anxiety development. These findings suggest that ICD patients are an appropriate risk population for a prospective study of the development of anxiety disorders.     

Maternal perspectives on children's health-related quality of life during the first year after pediatric hematopoietic stem cell transplant

OBJECTIVE: To assess the longitudinal health-related quality of life (HRQL) of children receiving hematopoietic stem cell transplantation (HSCT). METHODS: Mothers (N = 160) of HSCT recipients aged 5-20 at six US transplant centers completed the Child Health Ratings Inventories (CHRIs), the Disease Impairment Inventory (DSII)-HSCT module, and the Short Form (SF)-36 at baseline, 3, 6, and 12 months. RESULTS: HRQL domain scores at baseline varied by recipient age and program site. Longitudinal data over the first year post-HSCT revealed lowest functioning at baseline and 3 months, with largest improvement in functioning between the 3 and 6-months assessments and continued improvement from 6 to 12 months. Recipients of unrelated donor transplants had steepest declines in functioning at 3 months and great HSCT-specific issues at 3 and 6 months. Among children who survived the first year, functioning at 12 months was similar across transplant types and surpassed baseline scores. Children who did not survive the first year exhibited deterioration in HRQL in the months before death and trajectories were strikingly different than for survivors. CONCLUSIONS: This study offers the first glimpse of the 12-month trajectory of HRQL following pediatric HSCT from mothers' perspectives. This study also highlights the importance of and approaches to addressing missing data in longitudinal research.     

Primary renal tumours in the first year of life

Summary Of 30 patients presenting with primary renal tumours in the first year of life, there were 23 Wilms' tumours (15 classical, six epithelial and two rhabdomyomatous), three rhabdoid neoplasms and four mesoblastic nephromas. Criteria for the diagnosis of rhabdoid tumours and mesoblastic nephromas are discussed with reference to histological difficulties. Although Wilms' tumour was the commonest neoplasm, mesoblastic nephroma predominated in the first three months of life. The clinical behaviour of the cases is reviewed, and rhabdoid tumours, although relatively few in number, accounted for a significant part of the overall mortality.Consultant Pathologist to the Royal Manchester Children's Hospital. Honorary Lecturer in Pathology, University of ManchesterSenior Lecturer in Pathology and Honorary Consultant Pathologist     

Mouse exposure and wheeze in the first year of life.

BACKGROUND: Studies have found that exposure to mice is highly prevalent among children with asthma living in urban areas. OBJECTIVE: To examine the relationship between exposure to mice and wheeze in the first year of life. METHODS: We conducted an ongoing prospective birth cohort study of 498 children with a history of allergy or asthma in at least 1 parent living in metropolitan Boston (the Home Allergens and Asthma Study). RESULTS: In a multivariate analysis, infants whose parents reported exposure to mice in the household had nearly twice the odds of developing any wheeze in the first year of life as children without exposure (odds ratio [OR], 1.83; 95% confidence interval [CI], 1.14-2.95; P = .01). Other variables associated with wheeze in the first year of life included low birth weight (OR, 1.77; 95% CI, 1.06-2.95; P = .03), having at least 1 lower respiratory tract illness (OR, 5.59; 95% CI, 3.46-9.04; P < .001), exposure to high levels of endotoxin at age 2 to 3 months (fourth quartile compared with first quartile: OR, 2.32; 95% CI, 1.19-4.54; P = .01), and exposure to cockroach allergen of 0.05 U/g of dust or more at age 2 to 3 months (OR, 1.83; 95% CI, 1.09-3.08; P = .02). CONCLUSION: Among children with a parental history of asthma or allergies, exposure to mice is associated with wheeze in the first year of life, independent of other factors.     

Seasonality and weight gain during the first year of life

A comparison is made between weight increments at 0–3, 4–6, 7–9, and 10–12 months of life between infants born in the fall, winter, spring, and summer seasons in Sui Lin, Taiwan. The focus of the study is on (1) whether in a tropical region the effects of seasonality on weight gain interact with the developmental stage of the infant and (2) whether these interactions are partly regulated by the growth history of the infant. The main hypothesis is that the highest growth velocities will occur in the dry, cold months of the year (fall and winter) and the lowest velocities will occur in the hot, rainy months (spring and summer). The highest and lowest mean birth weights were recorded in the spring and summer seasons, respectively. Season had no effect on weight gain during 0–3 months; on the other hand, birth weight and length were significantly related to weight gain during this 0–3 month period. In the last two seasons of the first year, the highest weight increments occurred in the fall and the lowest occurred in the spring and summer. At the end of the 12 months of life there were no weight differences between cohorts.     

Home-based immunoglobulin infusion therapy: quality of life and patient health perceptions

Thirty-seven antibody-deficient patients who were participating in a multicenter trial evaluating home-based, self-administered IVIG therapy anonymously completed questionnaires regarding beliefs concerning health control, quality of life, and attitudes toward active participation in medical care. Their responses were compared with a group of 29 patients undergoing traditional IVIG therapy in a medical clinic setting. A subsample of the home-based group who later returned to clinic-based IVIG therapy allowed comparison of responses given by the same patients in both settings. Home-based therapy was preferred to clinic-based therapy. Independence, convenience, comfort, decreased disruption of activities, travel time, and costs were specific factors rated most favorably. On the Health Belief Questionnaires, patients preferred informed, self-involved medical care regardless of the setting for their IVIG treatments.