Patients' experiences of a suppoRted self-manAGeMent pAThway In breast Cancer (PRAGMATIC): quality of life and service use results

PURPOSE

To describe trends and explore factors associated with quality of life (QoL) and psychological morbidity and assess breast cancer (BC) health service use over a 12-month period for patients joining the supported self-management (SSM)/patient-initiated follow-up (PIFU) pathway.

METHODS

Participants completed questionnaires at baseline, 3, 6, 9 and 12 months that measured QoL (FACT-B, EQ 5D-5L), self-efficacy (GSE), psychological morbidity (GHQ-12), roles and responsibilities (PRRS) and service use (cost diary).

RESULTS

99/110 patients completed all timepoints; 32% (35/110) had received chemotherapy. The chemotherapy group had poorer QoL; FACT-B total score mean differences were 8.53 (95% CI: 3.42 to 13.64), 5.38 (95% CI: 0.17 to 10.58) and 8.00 (95% CI: 2.76 to 13.24) at 6, 9 and 12 months, respectively. The odds of psychological morbidity (GHQ12 >4) were 5.5-fold greater for those treated with chemotherapy. Financial and caring burdens (PRRS) were worse for this group (mean difference in change at 9 months 3.25 (95% CI: 0.42 to 6.07)). GSE and GHQ-12 scores impacted FACT-B total scores, indicating QoL decline for those with high baseline psychological morbidity. Chemotherapy patients or those with high psychological morbidity or were unable to carry out normal activities had the highest service costs. Over the 12 months, 68.2% participants phoned/emailed breast care nurses, and 53.3% visited a hospital breast clinician.

CONCLUSION

The data suggest that chemotherapy patients and/or those with heightened psychological morbidity might benefit from closer monitoring and/or supportive interventions whilst on the SSM/PIFU pathway. Reduced access due to COVID-19 could have affected service use.

Design, Synthesis, and Biological Characterization of Inhaled p38α/β MAPK Inhibitors for the Treatment of Lung Inflammatory Diseases

The identification of novel inhaled p38α/β mitogen-activated protein kinases (MAPK) (MAPK14/11) inhibitors suitable for the treatment of pulmonary inflammatory conditions has been described. A rational drug design approach started from the identification of a novel tetrahydronaphthalene series, characterized by nanomolar inhibition of p38α with selectivity over p38γ and p38δ isoforms. SAR optimization of 1c is outlined, where improvements in potency against p38α and ligand-enzyme dissociation kinetics led to several compounds showing pronounced anti-inflammatory effects in vitro (inhibition of TNFα release). Targeting of the defined physicochemical properties allowed the identification of compounds 3h, 4e, and 4f, which showed, upon intratracheal instillation, low plasma levels, prolonged lung retention, and anti-inflammatory effects in a rat acute model of a bacterial endotoxin-induced pulmonary inflammation. Compound 4e, in particular, displayed remarkable efficacy and duration of action and was selected for progression in disease models of asthma and chronic obstructive pulmonary disease (COPD).

Training in Clinical Oncology and the Transition from Trainee to Consultant: Results of the Royal College of Radiologists' 2015 Post-Certificate of Completion of Training Survey

AIMS

To seek feedback from clinical oncologists as to their experiences of specialty training and, where applicable, the transition to working as a consultant in the National Health Service.

MATERIALS AND METHODS

All clinical oncologists gaining a Certificate of Completion of Training between 1 July 2012 and 30 June 2014 were identified through records held by the Royal College of Radiologists and approached in May 2015 to take part in an online survey.

RESULTS

The survey was completed by 38 of 80 clinical oncologists invited to take part (48% response rate). Most respondents (>87%) agreed that specialty training equipped them well with clinical skills in radiotherapy planning, systemic therapy and tumour site diagnosis and treatment. This fell to 58% with advanced radiotherapy techniques. Of the non-clinical skills, respondents felt training had equipped them less to deal with leadership and management (53%) and research (48%) than clinical governance (61%). Despite wanting to do so, 42% of respondents did not undertake any out-of-programme (OOP) activity to gain new skills. Most of those respondents who did undertake OOP activity agreed that it helped to prepare them for their first consultant post. There is broad support for the FRCR Examination. The First FRCR Examination modules in physics, pharmacology, tumour biology and radiobiology were seen to be very relevant to clinical practice by 50% or more of respondents. The Final FRCR Examination was seen as essential in a technical specialty like clinical oncology by 92% of respondents. Working as a new consultant, the survey revealed a heavy workload for most respondents, with 69% always or almost always working beyond contracted hours. Other issues of concern identified were discrepancies in advertised consultant job plans and ineffectiveness of the job plan review process. The trainee-consultant transition is often a difficult time, yet only 19% of respondents were allocated a formal mentor. Most respondents had to rely on informal arrangements in seeking support and advice from medical colleagues.

CONCLUSIONS

In general, respondents were satisfied with their specialty training and the transition from training to working as a new consultant. Areas for possible improvement have been identified for employers as well as those involved in organising specialty training.

Abstract P1-13-03: Mature analysis of UK Taxotere as Adjuvant Chemotherapy (TACT) trial (CRUK 01/001); effects of treatment and characterisation of patterns of breast cancer relapse

Introduction: TACT, an investigator-led study in 4162 women with node positive (N+ve) or high risk node negative (N-ve) early breast cancer (EBC), is the largest taxane trial unconfounded by treatment (trt) duration. At principal analysis, with 5 years follow-up (fup), no evidence of improved disease-free survival (DFS) was observed by switching to 4 cycles of docetaxel (D) after 4 cycles of FEC (Ellis, Lancet 2009). Results were provocative in suggesting differential effects according to ER & HER2 status. Longer fup provides opportunity to detect emergence of late trt effects overall & within phenotypic subgroups & explore patterns of recurrence, by tumor characteristics.

Patients & methods: TACT recruited women with histologically confirmed completely resected invasive EBC from 104 centers (UK (103), Belgium (1)) between 02/2001 & 07/2003. Centers chose FEC (600/60/600 mg/m2 q3wk × 8) or E-CMF (E 100mg/m2 q3wk × 4 → CMF 100mg/m2 PO d1-14 or 600mg/m2 IV d1&8/40/600 mg/m2 q4wk × 4) as their control, reflecting standard UK practice. Patients (pts) were randomized to FEC-D (FEC q3wk × 4 → D 100 mg/m2 q3wk × 4) or control. 2523 pts were from FEC centers (FEC = 1265: FEC-D = 1258) & 1639 from E-CMF centers (E-CMF = 824; FEC-D = 815). Endocrine therapy was given for 5 years. Few pts received HER2 directed therapy; 589 pts had unknown HER2 status. Median fup is now 97.5 months; this analysis updates DFS & overall survival in the ITT population. It also explores patterns of relapse by phenotypic & clinical characteristics. Analyses of trt effect are stratified by ER status due to issues of non-proportionality of hazard associated with length of fup.

Results: DFS events have been reported for 1329 pts (FEC-D=640, Control=689) giving an unadjusted hazard ratio (HR) & 95%CI (stratified by control regimen & ER status) of 0.93 (0.83, 1.03) overall; p = 0.16 in favor of FEC-D & for ER+ve/HER2-ve of 0.99 (0.84, 1.17), for ER+ve/HER2+ve) 0.97 (0.73, 1.30), for ER-ve/HER2+ve 0.74 (0.53, 1.03), & ER-ve/HER2-ve 0.93 (0.73, 1.17). 1017 patients have died (FEC-D=500, Control=517); unadjusted HR=0.98 (95%CI: 0.86, 1.10); p = 0.69 with intercurrent deaths (prior to distant relapse) reported for 80 pts (FEC-D=40, Control=40).

Annual event rates show different pattern of disease relapse by phenotypic subgroup

Training in clinical oncology: results of the Royal College of Radiologists' survey of new consultants

AIMS

To seek the views of consultants appointed less than 2 years ago on the appropriateness of their training in fitting them to carry out their present posts, the FRCR examination, experience of research and the prevalence and value of out of programme experience and acting up as a consultant.

MATERIALS AND METHODS

All the consultants identified from the Royal College of Radiologists' database as having been appointed to a consultant post in the last 2 years were emailed inviting them to take part in a web-based survey.

RESULTS

The response rate was 60% (32 of 53 consultants). Ninety-four per cent agreed or strongly agreed that training had equipped them for clinical work as a consultant, but only 44% agreed or strongly agreed that training had equipped them to fulfil the management roles. Free text answers stressed the importance of management skills, getting involved with trial set-up and producing publications early in their career. Ninety-four per cent agreed or strongly agreed that they had adequate opportunity to develop skills in systemic therapy and radiotherapy planning, but only 56% thought this was the case for intensity-modulated radiotherapy and image-guided radiotherapy. Although 87% agreed or strongly agreed they had sufficient opportunity to develop teaching skills, this was only the case in 62% with regard to research skills. They published a median number of three papers in peer-reviewed journals. Twenty-five per cent of respondents studied for research degrees; 69% of consultants had undertaken out of programme experience and 50% had acted up as a consultant and these were generally found to be valuable experiences. There was strong support for the FRCR examination.

CONCLUSIONS

Consultants appointed in the last 2 years are generally satisfied with their training. Training in intensity-modulated radiotherapy and image-guided radiotherapy should be improved and the advanced specialist training requires reviewing to better fit consultants for subspecialisation, management and research.

The cost-effectiveness of adjuvant chemotherapy for early breast cancer: A comparison of no chemotherapy and first, second, and third generation regimens for patients with differing prognoses

BACKGROUND

The risk of recurrence following surgery in women with early breast cancer varies, depending upon prognostic factors. Adjuvant chemotherapy reduces this risk; however, increasingly effective regimens are associated with higher costs and toxicity profiles, making it likely that different regimens may be cost-effective for women with differing prognoses. To investigate this we performed a cost-effectiveness analysis of four treatment strategies: (1) no chemotherapy, (2) chemotherapy using cyclophosphamide, methotrexate, and fluorouracil (CMF) (a first generation regimen), (3) chemotherapy using Epirubicin-CMF (E-CMF) or fluorouracil, epirubicin, and cyclophosphamide (FEC60) (a second generation regimens), and (4) chemotherapy with FEC60 followed by docetaxel (FEC-D) (a third generation regimen). These adjuvant chemotherapy regimens were used in three large UK-led randomised controlled trials (RCTs).

METHODS

A Markov model was used to simulate the natural progression of early breast cancer and the impact of chemotherapy on modifying this process. The probability of a first recurrent event within the model was estimated for women with different prognostic risk profiles using a parametric regression-based survival model incorporating established prognostic factors. Other probabilities, treatment effects, costs and quality of life weights were estimated primarily using data from the three UK-led RCTs, a meta-analysis of all relevant RCTs, and other published literature. The model predicted the lifetime costs, quality adjusted life years (QALYs) and cost-effectiveness of the four strategies for women with differing prognoses. Sensitivity analyses investigated the impact of uncertain parameters and model assumptions.

FINDINGS

For women with an average to high risk of recurrence (based upon prognostic factors and any other adjuvant therapies received), FEC-D appeared most cost-effective assuming a threshold of £20,000 per QALY for the National Health Service (NHS). For younger low risk women, E-CMF/FEC60 tended to be the optimal strategy and, for some older low risk women, the model suggested a policy of no chemotherapy was cost-effective. For no patient group was CMF chemotherapy the preferred option. Sensitivity analyses demonstrated cost-effectiveness results to be particularly sensitive to the treatment effect estimate for FEC-D and the future price of docetaxel.

INTERPRETATION

To our knowledge, this analysis is the first cost-effectiveness comparison of no chemotherapy, and first, second, and third generation adjuvant chemotherapy regimens for early breast cancer patients with differing prognoses. The results demonstrate the potential for different treatment strategies to be cost-effective for different types of patients. These findings may prove useful for policy makers attempting to formulate cost-effective treatment guidelines in the field of early breast cancer.

Modelling the cost-effectiveness of first, second and third generation polychemotherapy regimens in women with early breast cancer who have differing prognoses

Abstract #6106

Purpose: To use individual patient data from three sequential large UK randomised trials to facilitate an integrated comparison of the cost-effectiveness of three generations of chemotherapy plus a no treatment option. The ABC trial compared CMF versus no chemo (1991 patients), NEAT trial Epirubicin-CMF versus CMF (2391 patients) and TACT FEC-Docetaxel vs FEC or epi-CMF (4162 patients)
 Methods: The model estimates lifetime costs and Quality-Adjusted Life Years (QALYs). Model inputs include transition probabilities which are estimated from a longitudinal observational study using parametric survival models incorporating characteristics such as number of positive lymph nodes, ER status, grade and tumour size that allow analyses to be conducted for women with differing baseline prognoses. The effects of each chemotherapy regimen on preventing recurrence are taken from the above UK trials and are assumed to be additive on the log scale to facilitate previously untested comparisons. Costs and utility decrements associated with chemotherapy, its toxicity, and type of recurrent disease, are informed from the trial data and published literature. A secondary analysis is performed by basing the effects of each chemotherapy regimen on published meta-analyses based on individual level data that include RCTs conducted in a range of multi-national settings.
 Results: For a woman aged 50 years with 1 positive node, grade 2 tumour size 2cm, ECMF is expected to be the most cost-effective regimen. However, the cost-effectiveness of the chemotherapy options varies between women with different risk factors. On the basis of the results of the TACT trial, 3rd generation chemotherapy is not cost-effective, but including evidence of the relative risk of recurrence from non-UK trials, particularly those with ER- and HER2+ phenotype, may alter this conclusion.
 Indicative lifetime costs and QALYs for a woman aged 50 years, with 1 positive node, grade 2 tumor size 2cm, with and without ER+ are shown:
 
 
 
 Conclusions: Evaluating the cost-effectiveness of chemotherapy regimens in women with early breast cancer who have differing prognoses is feasible using an integrative synthesis and model. Thought does, however, need to be given to how best present cost-effectiveness results when there are differing levels of baseline risk.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6106.

2,5-Disubstituted pyridines: the discovery of a novel series of 5-HT2A ligands

This report describes the effect of replacing the central basic amine present in many known 5-HT(2A) ligands with an aromatic residue. We targeted the isomeric phenethylpyridines 2 and 3 and these compounds proved to be excellent leads, possessing good 5-HT(2A) receptor binding affinity and selectivity over the 5-HT(2C) subtype. Optimization of one isomer led to the identification of 25, a compound with sub-nanomolar 5-HT(2A) affinity and selectivity over 5-HT(2C) of greater than 4600-fold.

The changing pattern of management for hormone-refractory, metastatic prostate cancer

Prostate cancer responds initially to hormonal manipulation by androgen withdrawal and peripheral androgen blockade. The inevitable progression to a hormone-refractory state is accompanied by an exacerbation of local symptoms and metastatic spread, principally to the bones, which has a considerable impact on quality of life and survival. Treatment of hormone-refractory prostate cancer is palliative, and surgery and radiotherapy are used for the relief of lower urinary tract symptoms and localized painful bony metastases. Systemic treatments are not widely accepted in this setting, but clinical trials have demonstrated the potential for bone targeting agents such as strontium-89 and the bisphosphonates to palliate painful bone metastases and to delay progression in certain settings. Chemotherapy with mitozantrone in combination with steroids has previously been shown to have palliative benefits and to delay progression. The additional costs incurred by the use of chemotherapy or bone-targeting therapies may be offset by gains in overall care with fewer in-patient admissions compared with steroid monotherapy. Recent clinical trials have demonstrated that docetaxel significantly improves patient quality of life, and importantly, increases survival. Future studies investigating the timing of chemotherapy, combinations with existing treatments or other novel therapies are underway.

A 3-year prospective study of the effects of adjuvant treatments on cognition in women with early stage breast cancer

The neuropsychological performance of 85 women with early stage breast cancer scheduled for chemotherapy, 43 women scheduled for endocrine therapy and/or radiotherapy and 49 healthy control subjects was assessed at baseline (T1), postchemotherapy (or 6 months) (T2) and at 18 months (T3). Repeated measures analysis found no significant interactions or main effect of group after controlling for age and intelligence. Using a calculation to examine performance at an individual level, reliable decline on multiple tasks was seen in 20% of chemotherapy patients, 26% of nonchemotherapy patients and 18% of controls at T2 (18%, 14 and 11%, respectively, at T3). Patients who had experienced a treatment-induced menopause were more likely to show reliable decline on multiple measures at T2 (OR=2.6, 95% confidence interval (CI) 0.823–8.266 P=0.086). Psychological distress, quality of life measures and self-reported cognitive failures did not impact on objective tests of cognitive function, but were significantly associated with each other. The results show that a few women experienced objective measurable change in their concentration and memory following standard adjuvant therapy, but the majority were either unaffected or even improve over time.

The effects of adjuvant chemotherapy on cognition in women with breast cancer--preliminary results of an observational longitudinal study

Several studies have reported that chemotherapy-treated patients have impaired cognition function relative to control groups. We are conducting a longitudinal study with cognitive assessments at baseline, 6 and 18 months. A planned preliminary analysis of data from 50 chemotherapy patients and 43 healthy controls at baseline and post-treatment found a significant group by time interaction on three measures of verbal and working memory. Chemotherapy patients were more likely to show cognitive decline than controls (OR 2.25). Patients were significantly more likely to have GHQ(12) scores indicative of possible psychological morbidity and showed significant increases in endocrine symptoms and fatigue post-treatment however neither GHQ(12) nor quality-of-life variables were related to cognitive performance.

Giving patients a choice improves quality of life: a multi-centre, investigator-blind, randomised, crossover study comparing letrozole with anastrozole

AIMS

Although the third-generation aromatase inhibitors are generally well tolerated, side-effects still occur in up to 40% of women. As more women are taking these drugs for longer, the issue as to which version is better tolerated is now a significant patient concern. This study aimed to assess whether tolerance for either letrozole or anastrozole can differ for each individual in terms of early quality of life (QoL), whether patients welcome being given a preference and whether this correlated with formal toxicity scoring.

MATERIALS AND METHODS

A single-blind, crossover trial, with 72 women with breast cancer who had experienced tamoxifen failure. Randomised to either letrozole 2.5 mg or anastrozole 1 mg, for 4 weeks, 1 week off, then crossover for 4 weeks.

RESULTS

Patients were confidently able to choose which drug suited them best (letrozole 68%, anastrozole 32%; P < 0.01). Fewer patients, when taking letrozole, experienced adverse events than when taking anastrozole (43% vs 65%; P = 0.0028). QoL was better when patients were taking letrozole than when they took anastrozole (P = 0.02).

CONCLUSIONS

As toxicity and QoL strongly correlated with patient preference for either drug, albeit with a tendency towards letrozole, this suggests that patient preference is now a legitimate and useful end point for future crossover studies. In routine practice, women would warmly welcome extra involvement in the decision-making process via a crossover manoeuvre if side-effects develop, whichever aromatase inhibitor is prescribed initially.

Midodrine prevents orthostatic intolerance associated with simulated spaceflight

Many astronauts after being weightless in space become hypotensive and presyncopal when they assume an upright position. This phenomenon, known as orthostatic intolerance, may interfere with astronaut function during reentry and after spaceflight and may limit the ability of an astronaut to exit a landed spacecraft unaided during an emergency. Orthostatic intolerance is more pronounced after long-term spaceflight and is a major concern with respect to the extended flights expected aboard the International Space Station and for interplanetary exploration class missions, such as a human mission to Mars. Fully effective countermeasures to this problem have not yet been developed. To test the hypothesis that α-adrenergic stimulation might provide an effective countermeasure, we conducted a 16-day head-down-tilt bed-rest study (an analog of weightlessness) using normal human volunteers and administered the α1-agonist drug midodrine at the end of the bed-rest period. Midodrine was found to significantly ameliorate excessive decreases in blood pressure and presyncope during a provocative tilt test. We conclude that midodrine may be an effective countermeasure for the prevention of orthostatic intolerance following spaceflight.

Psoriasis and radiotherapy: exacerbation of psoriasis following radiotherapy for carcinoma of the breast (the Koebner phenomenon)

We report the case history of a patient with a known history of psoriasis, who developed an exacerbation of the treated skin area after radiotherapy for carcinoma of the breast. This illustrates the Koebner phenomenon, with the replication of a dermatosis at the site of skin trauma.

Effects of age on outcome of tilt-table testing

Although neurally mediated syncope is thought to be common in the young and rare in the elderly, there are few data evaluating the effects of age on the outcome of tilt-table testing (TTT), especially in patients aged > or =80 years. We examined the results of TTT in 352 subjects with unexplained syncope including 133 patients >65 years of age and 43 patients >80 years of age. The average age was 54 +/- 20.8 years (range 11 to 99) and 51% were men. The TTT protocol included at least 45 minutes of upright tilt in the drug-free state with or without repeat TTT with isoproterenol or 15 minutes of upright tilt in the drug-free state followed by repeat TTT with isoproterenol. One hundred sixty-four subjects (47%) had a positive TTT. As expected, there was an age-related decline in positive TTT. A high proportion of elderly patients with unexplained syncope had a positive TTT (37% of patients aged > or =65, and 23% patients aged > or =80). Thus, TTT is a useful diagnostic test in patients aged > or =65 years with unexplained syncope.

Identification of intermediate-risk prostate cancer patients treated with radiotherapy suitable for neoadjuvant hormone studies

We undertook a retrospective review of patients presenting with apparently localised prostatic carcinoma to a single practitioner for consideration of radiation therapy to clarify the characteristics of those patients who might benefit from the use of neo-adjuvant androgen deprivation. Of 133 patients referred between January 1989 and June 1994, 85 were considered suitable for radical therapy, of whom 31 were treated with hormone therapy prior to radiotherapy, frequently on the basis of an elevated PSA. Increasing PSA levels (p = 0.0016) and Gleason grade (p = 0.026) were independent variables for relapse. It was possible to define three prognostic groups of patients, on the basis of initial PSA and Gleason grade. Those of intermediate risk (PSA < 10 micrograms/l, Gleason score 8-10; PSA 10-25 micrograms/l, Gleason 5-7 or 8-10; PSA > 25 micrograms/l, Gleason score 2-4) had a superior duration of disease-free survival if given initial hormone therapy. This group of patients is potentially the most likely to benefit from such an approach and should be enrolled in prospective randomised studies of neoadjuvant androgen deprivation.

The herpes-specific immune response of individuals with herpes-associated erythema multiforme compared with that of individuals with recurrent herpes labialis

Infection with herpes simplex virus (HSV) is the most common precipitating factor in the development of erythema multiforme (EM). It is not known why only a few of the many individuals who experience recurrent HSV infection also develop herpes-associated EM (HAEM), although a difference in the HSV-specific immune response has been postulated. The purpose of this study was to compare the HSV-specific immune response of individuals with HSV infection alone with that of individuals with HAEM. There were 21 patients in each of the two groups. Four parameters of the HSV-specific immune response were examined: (1) anti-HSV IgG titers were measured by ELISA; (2) antibody neutralization was assessed using a plaque assay; and (3) antibody-dependent complement-mediated cytotoxicity, and (4) antibody-dependent cellular cytotoxicity were investigated using a previously described in vitro HSV-specific cytotoxicity assay. No statistically significant differences were detected between the two patient groups. Thus, a difference in these HSV-specific immune mechanisms does not explain the development of HAEM in some individuals with recurrent HSV infection.

Spectral turbulence analysis of the signal-averaged electrocardiogram and its predictive accuracy for inducible sustained monomorphic ventricular tachycardia

This study was designed to assess the accuracy of a new noninvasive frequency analysis method for predicting patients with inducible sustained monomorphic ventricular tachycardia (VT) at electrophysiologic study and hence the risk of spontaneous ventricular tachyarrhythmias. Signal-averaged electrocardiograms from 3 orthogonal bipolar surface leads were evaluated using a microcomputer-based frequency analysis system that performs analysis of conventional time-domain late potentials as well as incorporating a new technique for spectral analysis of relatively short, overlapping signal segments spanning the whole QRS complex. The spectral analysis technique measured abnormalities anywhere in the entire QRS complex and did so without dependence on any arbitrarily defined frequency, duration or amplitude cutoffs. The hallmark of arrhythmogenic abnormality was hypothesized to be frequent and abrupt changes in the frequency signature of the QRS wave front velocity as it propagates throughout the ventricle around areas of abnormal conduction, resulting in a high degree of spectral turbulence. One-hundred forty-two subjects were studied, including 71 totally normal control subjects ("true negatives"), 33 with both late potentials by time-domain analysis and inducible sustained monomorphic VT ("true positives"), 28 with late potentials but no evidence of spontaneous or inducible sustained monomorphic VT ("false positives") and 10 with inducible sustained monomorphic VT but absence of time-domain late potentials ("false negatives"). The frequency analysis technique correctly classified 100% of the true negatives, 97% of the true positives, 86% of the late potentials false positives and 60% of the late potentials false negatives. The total predictive accuracy of frequency analysis for all groups was 94%, compared with 73% for time-domain late potential analysis. The results suggest that a high degree of spectral turbulence of the overall QRS signal during sinus rhythm may provide a more accurate marker for the anatomic-electrophysiologic substrate of reentrant tachyarrhythmias than detection of late potentials in the terminal QRS region by either time- or frequency-domain analysis. Spectral turbulence analysis is applicable to patients irrespective of the QRS duration and the presence or absence of bundle branch block.

Correlation between the signal-averaged electrocardiogram from Holter tapes and from real-time recordings

Signal-averaged electrocardiograms obtained from 3-channel Holter recordings were compared, using the same skin electrodes, with signal-averaged real-time recordings in 32 subjects. The numeric late potential parameters and morphologic appearances correlated closely between the 2 methods. The restricted high frequency response of Holter systems appears not to militate against clinically useful late potential analysis from Holter tape. This study suggests that diagnostic accuracy using real-time 25 to 250-Hz criteria is acceptable for clinical use until criteria derived specifically for Holter applications become available. Holter analysis may confer significant benefits resulting from an ability to perform late potential analysis on the same tape used for conventional arrhythmia analysis, and would allow future studies of possible dynamic changes of late potentials in relation to transient ischemia and spontaneous ventricular tachyarrhythmias.

A control-free ventilator alarm

An alarm for use with positive-pressure lung ventilators is described. The device gives audible warning if the pressure in the patient circuit fails either to exceed or to fall below 15 cmH2O within a period of 20 seconds or if the batteries are running low. No external controls are provided and the alarm is activated when a probe connected to the breathing circuit is inserted into the alarm. The probe whistles if incorrectly connected during intermittent positive pressure ventilation. Battery life in clinical practice is longer than 6 months.