Pre-exercise screening and health coaching in CHD secondary prevention: a qualitative study of the patient experience.

Secondary prevention programmes can be effective in reducing morbidity and mortality from coronary heart disease (CHD). In particular, UK guidelines, including those from the Department of Health, emphasize physical activity. However, the effects of secondary prevention programmes with an exercise component are moderate and uptake is highly variable. In order to explore patients' experiences of a pre-exercise screening and health coaching programme (involving one-to-one consultations to support exercise behaviour change), semi-structured telephone interviews were undertaken with 84 CHD patients recruited from primary care. The interviews focused on patients' experiences of the intervention including referral and any recommendations for improvement. A thematic analysis of transcribed interviews showed that the majority of patients were positive about referral. However, patients also identified a number of barriers to attending and completing the programme, including a belief they were sufficiently active already, the existence of other health problems, feeling unsupported in community-based exercise classes and competing demands. Our findings highlight important issues around the choice of an appropriate point of intervention for programmes of this kind as well as the importance of appropriate patient selection, suggesting that the effectiveness of health coaching may be under-reported as a result of including patients who are not yet ready to change their behaviours.

A randomized, controlled trial to study the effect of exercise consultation on the promotion of physical activity in people with Type 2 diabetes: a pilot study.

AIM: To evaluate the effect of exercise consultation on promotion of physical activity in people with Type 2 diabetes. METHODS: Twenty-six sedentary people with Type 2 diabetes were randomly assigned to receive an exercise consultation and standard exercise information (experimental) or standard exercise information alone (control). Exercise consultation is a one-to-one discussion, based on the transtheoretical model, designed to educate, strengthen motivation and develop realistic strategies to promote physical activity. Changes from baseline at five weeks were assessed in (a) stage of exercise behaviour (b) physical activity levels (7-day recall questionnaire and an accelerometer) (c) quality of life (SF-36 Health Survey and 22-Item Well-Being Questionnaire). RESULTS: 82% (9/11) of participants receiving a consultation increased their stage of exercise behaviour compared to 33% (4/12) of controls (chi2 = 5.4, P = 0.02). Physical activity counts/week increased by 4% (1636 067/1696 191) in the experimental group and decreased by 9% (1560 960/1725 510) in controls. A significant difference was recorded for the change in activity counts per week from baseline to follow-up between the experimental and control group (98% CI = 60 673-710 827). The number of participants taking part in sport or leisure activity increased by 55% (6/11) in the experimental group and decreased by 6% (1/12) in controls. Positive changes were evident in the experimental group, compared to controls, in both quality of life questionnaires. CONCLUSION: Exercise consultation is more effective in stimulating exercise behaviour change in the short term than a standard exercise leaflet.

Sumatriptan reduces exercise capacity in healthy males: a peripheral effect of 5-hydroxytryptamine agonism?

5-Hydroxytryptamine (5-HT; serotonin) has been implicated in the perception of exercise-induced fatigue. Sumatriptan is a selective 5-HT(1B/D) receptor agonist which does not cross the blood-brain barrier. The aim of the present study was to determine the effect of sumatriptan on exercise capacity. Ten healthy male subjects (mean age 28.4+/-10.8 years) performed a maximal treadmill exercise test according to the Bruce protocol with expired gas analysis on two occasions. Either 6 mg of sumatriptan or placebo was administered subcutaneously in a randomized, double-blind, placebo-controlled, cross-over design. Exercise time was greater after placebo compared with sumatriptan [914 and 879 s respectively; 95% confidence interval (CI) of difference 12.1 s, 59.1 s; P = 0.008]. There was no significant effect on peak oxygen consumption (placebo, 50.6+/-6.3 ml.min(-1).kg(-1); sumatriptan, 51.7+/-7.6 ml.min(-1).kg(-1)). Sumatriptan administration resulted in decreases in both heart rate (sumatriptan, 188+/-14 beats/min, placebo, 196+/-12 beats/min; 95% CI of difference 12.6, 2.6; P = 0.008) and respiratory exchange ratio (sumatriptan, 1.23+/-0.06; placebo, 1.26+/-0.07; 95% CI of difference 0.05, 0.01; P = 0.01) at peak exercise. There were no significant differences in blood pressure, heart rate or submaximal oxygen consumption between sumatriptan and placebo treatments at any stage of exercise. Thus sumatriptan reduces maximal exercise capacity in normal males. The failure to demonstrate any haemodynamic or cardiorespiratory effect suggests that sumatriptan enhances perception of fatigue by a peripheral mechanism affecting 5-HT modulation.

Changes in systolic time intervals-a non-invasive marker for the haemodynamic effects of sumatriptan.

AIMS: This study assessed the use of systolic time intervals (STI) as a potential non-invasive marker of the haemodynamic effects of sumatriptan, a 5HT1 receptor agonist. METHODS: Twenty-six patients undergoing diagnostic cardiac catheterization participated. STIs were derived from haemodynamic pressure tracings at baseline, following placebo injection and following either subcutaneous (n=18) or intravenous injection (n=8) of sumatriptan. RESULTS: Sumatriptan (i.v. or s.c.) was associated with significant increases in mean arterial pressure (95% C.I. 9,14mmHg, P=0.0001), total electromechanical systole (95% C.I.8,36ms, P<0.0001), pre-ejection period (95%C.I. 8,21ms, P=0.0001) and left ventricular ejection time (95% C.I. 2,12ms, P=0.004). Conclusion STI responses were consistent with sumatriptan-induced changes in afterload. In summary, the measurement of STIs is a potential non-invasive method of investigating the influence of serotonergic compounds on the cardiovascular system.

Blind atrial pacing for patients with sinus node disease who develop atrial fibrillation during permanent pacemaker implantation.

During a 6-year period, six of 110 patients implanted with AAI pacemakers for sick sinus syndrome developed atrial fibrillation at the time of pacemaker implantation (5.5%). In all cases a passive fixation lead was sited in the right atrial appendage, its stability being ensured by rotation of the lead and phrenic nerve stimulation excluded by pacing at 10 V. One patient remained in chronic atrial fibrillation. In the other five, who subsequently reverted to sinus rhythm, atrial P-wave sensing and lead threshold values were satisfactory, allowing programming of the pacemaker output down to 2.5 V to conserve the battery. One out of these five patients continued to have intermittent atrial fibrillation. We conclude that in sick sinus syndrome, atrial fibrillation complicates AAI pacemaker implantation procedure in 5.5% of cases. As an alternative to an unplanned general anaesthetic to cardiovert the patient, it is reasonable to implant an atrial lead in the right atrial appendage in the expectation of a spontaneous reversion to sinus rhythm with a good lead threshold and P-wave sensing. In contrast to inappropriate pacing of the right ventricle in VVI mode, this strategy avoids pacemaker syndrome and reduces the risk of subsequent attacks of atrial fibrillation.

Effect of subcutaneous sumatriptan, a selective 5HT1 agonist, on the systemic, pulmonary, and coronary circulation.

BACKGROUND: Sumatriptan (GR43175) is a selective 5-hydroxytryptamine (5HT1) receptor agonist effective in the acute treatment of migraine. Recent in vitro experiments suggest that it has vasoactive properties in vascular beds distinct from the cerebral circulation. The object of this study was to assess the vasoactive effects of the standard 6-mg subcutaneous dose of sumatriptan used in migraine on the systemic and pulmonary circulations and the coronary artery vasculature. METHODS AND RESULTS: Ten patients undergoing diagnostic coronary arteriography were studied with digital subtraction angiography and invasive hemodynamic monitoring. After subcutaneous injection of sumatriptan, there was no significant change in heart rate or ECG morphology. There was a significant rise in the systemic (20%, p < 0.05 by ANOVA) and pulmonary artery (40%, p < 0.05 by ANOVA) pressures. There was no change in cardiac output, but there was a significant increase in total systemic (27%, p < 0.05) and total pulmonary vascular resistance (40%, p < 0.05). Sumatriptan caused a significant reduction (p < 0.001 by ANOVA) in mean absolute coronary artery diameter, from 4.36 +/- 1.60 mm at baseline to 3.67 +/- 1.49 mm (16%) at 10 minutes and to 3.63 +/- 1.49 mm (17%) at 30 minutes after injection. There were no clinical sequelae. CONCLUSIONS: Sumatriptan, a 5HT1 receptor agonist administered by the subcutaneous route, causes a vasopressor response in the systemic and pulmonary arterial circulations and coronary artery vasoconstriction.

The effect of i.v. sumatriptan, a selective 5-HT1-receptor agonist on central haemodynamics and the coronary circulation.

1. Sumatriptan (GR43175) is a selective 5-HT1-receptor agonist effective in the acute treatment of migraine. Vasoactive properties in other vascular beds have been suggested by recent in vitro studies. 2. Its effects on coronary artery dimensions and central haemodynamics were assessed in 10 patients undergoing diagnostic coronary arteriography using digital subtraction angiography and invasive haemodynamic monitoring. 3. Following a 10 min i.v. infusion of sumatriptan to a total dose of 48 micrograms kg-1 there was a significant increase (P < 0.05) in systemic and pulmonary arterial pressures. There was a significant reduction in coronary artery diameter from 4.3 +/- 1.6 mm to 3.6 +/- 1.6 mm 12.9 +/- 6.9% (P < 0.001). There was no significant change in heart rate or ECG morphology. 4. Sumatriptan, a 5-HT1-receptor agonist, causes a vasopressor response in the systemic and pulmonary arterial circulations and coronary artery vasoconstriction; in this study there were no clinical sequelae.

A pilot study of the efficacy and safety of bolus administration of alteplase in acute myocardial infarction.

OBJECTIVE: To examine the efficacy, safety, and the pharmacokinetic profile of a bolus dose administration regimen of alteplase in the treatment of acute myocardial infarction. DESIGN: An open pilot study. SETTING: District general hospital. PATIENTS: 33 suitable consecutive patients presenting within six hours of the onset of symptoms who satisfied the electrocardiographic criteria for acute myocardial infarction. INTERVENTIONS: Two intravenous boluses of 35 mg alteplase, 30 minutes apart. MAIN OUTCOME MEASURES: Angiographic coronary patency at 90 minutes and 24 hours. Plasma alteplase concentration-time profile and pharmacokinetic analysis. RESULTS: Coronary patency at 90 minutes: 26 of 30 arteries (87%, 95% confidence interval (CI) 74-99%). Coronary patency at 24 hours: 24 of 29 arteries (83%, CI 69-97%). Mean (SD) plasma tissue plasminogen activator (t-PA) concentration reached 4434.8 (2117.8) and 4233.3 (2217.5) ng/ml within 10 minutes of each bolus and fell to 425.8 (288.3) ng/ml between boluses. The estimated peak concentrations at two minutes after boluses were 12,389 (8580) ng/ml and 10,811 (6802) ng/ml. The derived pharmacokinetic variables were volume of distribution 3.11 (1.89) 1, clearance 21.3 (9.3) 1/h, half life 5.9 (1.7) minutes. CONCLUSIONS: This simple administration regimen achieved brief, high concentrations of plasma t-PA that were well tolerated. The regimen was associated with a high coronary patency rate at 90 minutes that was well maintained at 24 hours.