Promoting Health Behaviour Change in the Cardiac Patient

The importance of giving patients advice in relation to positive health behaviour change geared towards maximizing physical health must not be overlooked and is an important role of the cardiac nurse in contemporary health care. However, over-reliance on offering advice can often be counter-productive and less likely to achieve effective change. Patients are more likely to make positive health behaviour changes when they self-generate their own solutions to the health issues and problems that they face. In this article, the authors encourage cardiac nurses to embrace a less directive and more facilitative approach to patient health behaviour change in light of the mounting evidence that exists to the effectiveness of motivational interviewing techniques.

Using simulation to assess cardiac first-responder schemes exhibiting stochastic and spatial complexities

A Monte-Carlo simulation-based model has been constructed to assess a public health scheme involving mobile-volunteer cardiac First-Responders. The scheme being assessed aims to improve survival of Sudden-Cardiac-Arrest (SCA) patients, through reducing the time until administration of life-saving defibrillation treatment, with volunteers being paged to respond to possible SCA incidents alongside the Emergency Medical Services. The need for a model, for example, to assess the impact of the scheme in different geographical regions, was apparent upon collection of observational trial data (given it exhibited stochastic and spatial complexities). The simulation-based model developed has been validated and then used to assess the scheme's benefits in an alternative rural region (not a part of the original trial). These illustrative results conclude that the scheme may not be the most efficient use of National Health Service resources in this geographical region, thus demonstrating the importance and usefulness of simulation modelling in aiding decision making.

Assessing quality of life in cardiac rehabilitation: Choosing an appropriate tool

Quality of life is an important outcome for people undergoing cardiac rehabilitation. This paper discusses the difficulties with defining the concept of quality of life and how it might be distinct from the concept of health-related quality of life. Based on a review of the literature, a description is provided of health-related quality of life questionnaires that have been used in cardiac rehabilitation populations. Some criteria for choosing between these questionnaires are then discussed and, finally, a brief discussion is presented of the concept of response shift and how this might influence the assessment of health-related quality of life in a cardiac rehabilitation setting.

The cardiac responses of the scallop Pecten maximus (L.) to respiratory stress

Heart activity of Pecten maximus (L.) has been recorded during various forms of experimentally induced respiratory stress. There was considerable variation in the responses of individual scallops but bradycardia generally occurred in response to all forms of respiratory stress, with the rate of fall in heart rate dependent upon the severity of hypoxia. When oxygen tension declined slowly in a closed respirometer there was regulation of both heart rate and oxygen consumption. The critical tension, Pc, for oxygen consumption lay between 70 and 80 mm Hg, and corresponded with a slight regulatory upswing of the heart rate, whereas the Pc for heart rate was much lower at 20–30 mm Hg. Sudden transfer to deoxygenated water for 3 h resulted in very rapid bradycardia and there was a rapid recovery and initial overshoot of the normal rate on return to well-oxygenated sea water. Aerial exposure for 3 h produced more gradual bradycardia followed by gradual recovery on return to sea water. The results of this work are compared in some detail with previous work on other species of bivalve from different geographical areas and habitats, and the mechanisms controlling cardiac and respiratory regulation are discussed. It is concluded that there are few clear-cut general differences between littoral and sublittoral species in their behavioural and physiological adaptations to hypoxia; the main distinguishing feature of littoral-adapted species is their ability to control air-gaping. Changes in heart activity generally indicate variations in metabolic rate, the speed at which the metabolic rate may be altered reflecting the degree of adaptation to the littoral environment.

Unconscious Vigilance: Worldview Defense without Adaptations for Terror, Coalition or Uncertainty Management

Individuals subtly reminded of death, coalitional challenges, or feelings of uncertainty display exaggerated preferences for affirmations and against criticisms of their cultural in-groups. Terror management, coalitional psychology, and uncertainty management theories postulate this “worldview defense” effectas the output of mechanisms evolved either to allay the fear of death, foster social support, or reduce anxiety by increasing adherence to cultural values. In 4 studies, we report evidence for an alternative perspective. We argue that worldview defense owes to unconscious vigilance, a state of accentuatedreactivity to affective targets (which need not relate to cultural worldviews) that follows detection of subtle alarm cues (which need not pertain to death, coalitional challenges, or uncertainty). In Studies 1 and 2, death-primed participants produced exaggerated ratings of worldview-neutral affective targets. In Studies 3 and 4, subliminal threat manipulations unrelated to death, coalitional challenges, or uncertaintyevoked worldview defense. These results are discussed as they inform evolutionary interpretations of worldview defense and future investigations of the influence of unconscious alarm on judgment.

AM1- receptor dependent protection by intermedin of human vascular and cardiac non-vascular cells from ischaemia-reperfusion injury

Intermedin (IMD) protects rodent heart and vasculature from oxidative stress and ischaemia. Less is known about distribution of IMD and its receptors and the potential for similar protection in man. Expression of IMD and receptor components were studied in human aortic endothelium cells (HAECs), smooth muscle cells (HASMCs), cardiac microvascular endothelium cells (HMVECs) and fibroblasts (v-HCFs). Receptor subtype involvement in protection by IMD against injury by hydrogen peroxide (H2O2, 1 mmol l?¹) and simulated ischaemia and reperfusion were investigated using receptor component-specific siRNAs. IMD and CRLR, RAMP1, RAMP2 and RAMP3 were expressed in all cell types.When cells were treated with 1 nmol l?¹ IMD during exposure to 1 mmol l?¹ H2O2 for 4 h, viability was greater vs. H2O2 alone (P<0.05 for all cell types). Viabilities under 6 h simulated ischaemia differed (P<0.05) in the absence and presence of 1 nmol l?¹ IMD: HAECs 63% and 85%; HMVECs 51% and 68%; v-HCFs 42% and 96%. IMD 1 nmol l?¹ present throughout ischaemia (3 h) and reperfusion (1 h) attenuated injury (P<0.05): viabilities were 95%, 74% and 82% for HAECs, HMVECs and v-HCFs, respectively, relative to those in the absence of IMD (62%, 35%, 32%, respectively). When IMD 1 nmol l?¹ was present during reperfusion only, protection was still evident (P<0.05, 79%, 55%, 48%, respectively). Cytoskeletal disruption and protein carbonyl formation followed similar patterns. Pre-treatment (4 days) of HAECs with CRLR or RAMP2, but not RAMP1 or RAMP3, siRNAs abolished protection by IMD (1 nmol l?¹) against ischaemia-reperfusion injury. IMD protects human vascular and cardiac non-vascular cells from oxidative stress and ischaemia-reperfusion,predominantly via AM1 receptors.

Voltage-activated currents in cardiac myocytes of the blue mussel, Mytilus edulis

Voltage-sensitive ionic currents were identified and characterised in ventricular myocytes of the bivalve mollusc, Mytilus edulis, using the whole-cell patch-clamp technique. Two outward currents could be distinguished. A potassium A current (I-A) activated at - 30 mV from a holding potential of - 60 mV. This transient current was inactivated by holding the cells at a potential of - 40 mV and was also blocked by applying 4-aminopyridine (3 mM) to the external bath solution. A second current was identified as a delayed rectifier (I-K). This also activated at - 30 mV but exhibited a sustained time course and was still activated at a holding potential of - 40 mV. Both outward currents were reduced in the presence of tetraethylammonium ions (30 mM). A small number of heart cells also showed an inward sodium current (I-Na). This current appeared at potentials more positive than - 50 mV, reached a maximum at - 20 mV, and decreased with further depolarisation. I-Na was inactivated at a holding potential of - 40 mV and was blocked by tetrodotoxin (1 mu M). A second inward current had a sustained time course and was not inactivated by holding the cell at a potential of -40 mV, and was also not abolished by tetrodotoxin. This current peaked at 0 mV, decreasing with further depolarisation. Furthermore, it was enhanced by the addition of barium ions (3 mM) to the bath and was blocked by external cobalt (2 mM) or nifedipine (15 mu M) These findings are consistent with this being an L-type calcium current (I-Ca) The possible physiological roles of these currents in M. edulis heart are discussed. (C) 1999 Elsevier Science Inc. All rights reserved.

Simultaneous, long-term monitoring of valve and cardiac activity in the blue mussel Mytilus edulis exposed to copper

Valve and cardiac activity were simultaneously measured in the blue mussel (Mytilus edulis) in response to 10 d copper exposure. Valve movements, heart rates and heart-rate variability were obtained non-invasively using a Musselmonitor(R) (valve activity) and a modified version of the Computer-Aided Physiological Monitoring system (CAPMON; cardiac activity). After 2 d exposure of mussels (4 individuals per treatment group) to a range of dissolved copper concentrations (0 to 12.5 mu M as CuCl2) median valve positions (% open) and median heart rates (beats per minute) declined as a function of copper concentration. Heart-rate variability (coefficient of variation for interpulse durations) rose in a concentration-dependent manner. The 48 h EC50 values (concentrations of copper causing 50% change) for valve positions, heart rates and heart-rate variability were 2.1, 0.8, and 0.06 mu M, respectively. Valve activity was weakly correlated with both heart rate (r = 0.48 +/- 0.02) and heart-rate variability (r = 0.32 +/- 0.06) for control individuals (0 mu M Cu2+). This resulted from a number of short enclosure events that did not coincide with a change in cardiac activity. Exposure of mussels to increasing copper concentrations (greater than or equal to 0.8 mu M) progressively reduced the correlation between valve activity and heart rates (r = 0 for individuals dosed with greater than or equal to 6.3 mu M Cu2+), while correlations between valve activity and heart-rate variability were unaffected. The poor correlations resulted from periods of valve flapping that were not mimicked by similar fluctuations in heart rate or heart-rate variability. The data suggest that the copper-induced bradycardia observed in mussels is not a consequence of prolonged valve closure.