The effects of cardiac output and pulmonary arterial hypertension on volumetric capnography derived-variables during normoxia and hypoxia

The aim of this study was to test the effect of cardiac output (CO) and pulmonary artery hypertension (PHT) on volumetric capnography (VCap) derived-variables. Nine pigs were mechanically ventilated using fixed ventilatory settings. Two steps of PHT were induced by IV infusion of a thromboxane analogue: PHT25 [mean pulmonary arterial pressure (MPAP) of 25 mmHg] and PHT40 (MPAP of 40 mmHg). CO was increased by 50 % from baseline (COup) with an infusion of dobutamine ≥5 μg kg(-1) min(-1) and decreased by 40 % from baseline (COdown) infusing sodium nitroglycerine ≥30 μg kg(-1) min(-1) plus esmolol 500 μg kg(-1) min(-1). Another state of PHT and COdown was induced by severe hypoxemia (FiO2 0.07). Invasive hemodynamic data and VCap were recorded and compared before and after each step using a mixed random effects model. Compared to baseline, the normalized slope of phase III (SnIII) increased by 32 % in PHT25 and by 22 % in PHT40. SnIII decreased non-significantly by 4 % with COdown. A combination of PHT and COdown associated with severe hypoxemia increased SnIII by 28 % compared to baseline. The elimination of CO2 per breath decreased by 7 % in PHT40 and by 12 % in COdown but increased only slightly with COup. Dead space variables did not change significantly along the protocol. At constant ventilation and body metabolism, pulmonary artery hypertension and decreases in CO had the biggest effects on the SnIII of the volumetric capnogram and on the elimination of CO2.

Primary prophylaxis for venous thromboembolism in patients undergoing cardiac or thoracic surgery.

BACKGROUND Cardiac and thoracic surgery are associated with an increased risk of venous thromboembolism (VTE). The safety and efficacy of primary thromboprophylaxis in patients undergoing these types of surgery is uncertain. OBJECTIVES To assess the effects of primary thromboprophylaxis on the incidence of symptomatic VTE and major bleeding in patients undergoing cardiac or thoracic surgery. SEARCH METHODS The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched May 2014) and CENTRAL (2014, Issue 4). The authors searched the reference lists of relevant studies, conference proceedings, and clinical trial registries. SELECTION CRITERIA Randomised controlled trials (RCTs) and quasi-RCTs comparing any oral or parenteral anticoagulant or mechanical intervention to no intervention or placebo, or comparing two different anticoagulants. DATA COLLECTION AND ANALYSIS We extracted data on methodological quality, participant characteristics, interventions, and outcomes including symptomatic VTE and major bleeding as the primary effectiveness and safety outcomes, respectively. MAIN RESULTS We identified 12 RCTs and one quasi-RCT (6923 participants), six for cardiac surgery (3359 participants) and seven for thoracic surgery (3564 participants). No study evaluated fondaparinux, the new oral direct thrombin, direct factor Xa inhibitors, or caval filters. All studies had major study design flaws and most lacked a placebo or no treatment control group. We typically graded the quality of the overall body of evidence for the various outcomes and comparisons as low, due to imprecise estimates of effect and risk of bias. We could not pool data because of the different comparisons and the lack of data. In cardiac surgery, 71 symptomatic VTEs occurred in 3040 participants from four studies. In a study of 2551 participants, representing 85% of the review population in cardiac surgery, the combination of unfractionated heparin with pneumatic compression stockings was associated with a 61% reduction of symptomatic VTE compared to unfractionated heparin alone (1.5% versus 4.0%; risk ratio (RR) 0.39; 95% confidence interval (CI) 0.23 to 0.64). Major bleeding was only reported in one study, which found a higher incidence with vitamin K antagonists compared to platelet inhibitors (11.3% versus 1.6%, RR 7.06; 95% CI 1.64 to 30.40). In thoracic surgery, 15 symptomatic VTEs occurred in 2890 participants from six studies. In the largest study evaluating unfractionated heparin versus an inactive control the rates of symptomatic VTE were 0.7% versus 0%, respectively, giving a RR of 6.71 (95% CI 0.40 to 112.65). There was insufficient evidence to determine if there was a difference in the risk of major bleeding from two studies evaluating fixed-dose versus weight-adjusted low molecular weight heparin (2.7% versus 8.1%, RR 0.33; 95% CI 0.07 to 1.60) and unfractionated heparin versus low molecular weight heparin (6% and 4%, RR 1.50; 95% CI 0.26 to 8.60). AUTHORS' CONCLUSIONS The evidence regarding the efficacy and safety of thromboprophylaxis in cardiac and thoracic surgery is limited. Data for important outcomes such as pulmonary embolism or major bleeding were often lacking. Given the uncertainties around the benefit-to-risk balance, no conclusions can be drawn and a case-by-case risk evaluation of VTE and bleeding remains preferable.

Preprocedural High-Sensitivity Cardiac Troponin T and Clinical Outcomes in Patients With Stable Coronary Artery Disease Undergoing Elective Percutaneous Coronary Intervention.

BACKGROUND Cardiac troponin detected by new-generation, highly sensitive assays predicts clinical outcomes among patients with stable coronary artery disease (SCAD) treated medically. The prognostic value of baseline high-sensitivity cardiac troponin T (hs-cTnT) elevation in SCAD patients undergoing elective percutaneous coronary interventions is not well established. This study assessed the association of preprocedural levels of hs-cTnT with 1-year clinical outcomes among SCAD patients undergoing percutaneous coronary intervention. METHODS AND RESULTS Between 2010 and 2014, 6974 consecutive patients were prospectively enrolled in the Bern Percutaneous Coronary Interventions Registry. Among patients with SCAD (n=2029), 527 (26%) had elevated preprocedural hs-cTnT above the upper reference limit of 14 ng/L. The primary end point, mortality within 1 year, occurred in 20 patients (1.4%) with normal hs-cTnT versus 39 patients (7.7%) with elevated baseline hs-cTnT (P<0.001). Patients with elevated hs-cTnT had increased risks of all-cause (hazard ratio 5.73; 95% confidence intervals 3.34-9.83; P<0.001) and cardiac mortality (hazard ratio 4.68; 95% confidence interval 2.12-10.31; P<0.001). Preprocedural hs-TnT elevation remained an independent predictor of 1-year mortality after adjustment for relevant risk factors, including age, sex, and renal failure (adjusted hazard ratio 2.08; 95% confidence interval 1.10-3.92; P=0.024). A graded mortality risk was observed across higher tertiles of elevated preprocedural hs-cTnT, but not among patients with hs-cTnT below the upper reference limit. CONCLUSIONS Preprocedural elevation of hs-cTnT is observed in one fourth of SCAD patients undergoing elective percutaneous coronary intervention. Increased levels of preprocedural hs-cTnT are proportionally related to the risk of death and emerged as independent predictors of all-cause mortality within 1 year. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT02241291.

Using clinical indicators in a quality improvement programme targeting cardiac care

Rationale. The Brisbane Cardiac Consortium, a quality improvement collaboration of clinicians from three hospitals and five divisions of general practice, developed and reported clinical indicators as measures of the quality of care received by patients with acute coronary syndromes or congestive heart failure. Development of indicators. An expert panel derived indicators that measured gaps between evidence and practice. Data collected from hospital records and general practice heart-check forms were used to calculate process and outcome indicators for each condition. Our indicators were reliable (kappa scores 0.7-1.0) and widely accepted by clinicians as having face validity. Independent review of indicator-failed, in-hospital cases revealed that, for 27 of 28 process indicators, clinically legitimate reasons for withholding specific interventions were found in

Paediatric telecardiology services in Queensland: a review of three years' experience

Videoconferencing at 384 kbit/s for the transmission of echocardiograms has proved useful for the assessment of children with suspected cardiac disease, in regional areas of Queensland. A retrospective review of patient and management outcomes was conducted on cardiac teleconsultations performed at two regional hospitals during the period November 2000 to February 2004, inclusive. There were 106 echo studies. A subset of 72 cardiac teleconsultations performed between May 2001 and February 2004 was reviewed in detail. The median age of patients at the time of consultation was 3 months (range 1 day-17 years). Sixteen per cent of teleconsultations were classified as urgent and were conducted on the same day as referral. Following the videoconference, 90% of patients could be managed locally and reviewed by the paediatrician or visiting paediatric cardiologist during an outreach clinic. Six children (8%) had significant cardiac lesions that were initially managed locally, with subsequent elective transfer at the appropriate time for treatment. Only one child (1%) required urgent transfer to the tertiary centre for specialist care and surgery. Telecardiology was effective in accurately identifying congenital heart disease. Paediatric telecardiology is an evolving modality of assessment and communication, and is likely to result in continued improvements in patient care, patient outcomes and parental satisfaction, in provincial centres removed from the tertiary cardiac centre.

Unmet health needs in patients with coronary heart disease: implications and potential for improvement in caring services

BACKGROUND: Improving the quality of health care services requires tailoring facilities to fulfil patients' needs. Satisfying patients' healthcare needs, listening to patients' opinions and building a closer provider-user partnership are central to the NHS. Few published studies have discussed cardiovascular patients' health needs, but they are not comprehensive and fail to explore the contribution of outcome to needs assessment. METHOD: A comprehensive self-administered health needs assessment (HNA) questionnaire was developed for concomitant use with generic (Short Form-12 and EuroQOL) and specific (Seattle Angina Questionnaire) health-related quality of life (HRQL) instruments on 242 patients admitted to the Acute Cardiac Unit, Nottingham. RESULTS: 38% reported difficulty accessing health facilities, 56% due to transport and 32% required a travelling companion. Mean HRQOL scores were lower in those living alone (P < 0.05) or who reported unsatisfactory accommodation. Dissatisfaction with transport affected patients' ease of access to healthcare facilities (P < 0.001). Younger patients (<65 y) were more likely to be socially isolated (P = 0.01). Women and patients with chronic disease were more likely to be concerned about housework (P < 0.05). Over 65 s (p < 0.05) of higher social classes (p < 0.01) and greater physical needs (p < 0.001) had more social needs, correlating moderately (0.32 < r < 0.63) with all HRQL domains except SAQ-AS. Several HRQL components were highly correlated with the HNA physical score (p < 0.001). CONCLUSIONS: Patients wanted more social (suitable accommodation, companionship, social visits) and physical (help aids, access to healthcare services, house work) support. The construct validity and intra-class reliability of the HNA tool were confirmed. Our results indicate a gap between patients' health needs and available services, highlighting potential areas for improvement in the quality of services

The HEART mobile phone trial: the partial mediating effects of self-efficacy on physical activity among cardiac patients

BACKGROUND: The ubiquitous use of mobile phones provides an ideal opportunity to deliver interventions to increase physical activity levels. Understanding potential mediators of such interventions is needed to increase their effectiveness. A recent randomized controlled trial of a mobile phone and Internet (mHealth) intervention was conducted in New Zealand to determine the effectiveness on exercise capacity and physical activity levels in addition to current cardiac rehabilitation (CR) services for people (n = 171) with ischemic heart disease. Significant intervention effect was observed for self-reported leisure-time physical activity and walking, but not peak oxygen uptake at 24 weeks. There was also significant improvement in self-efficacy.

OBJECTIVE: To evaluate the mediating effect of self-efficacy on physical activity levels in an mHealth delivered exercise CR program.

METHODS: Treatment evaluations were performed on the principle of intention to treat. Adjusted regression analyses were conducted to evaluate the main treatment effect on leisure-time physical activity and walking at 24 weeks, with and without change in self-efficacy as the mediator of interest.

RESULTS: Change in self-efficacy at 24 weeks significantly mediated the treatment effect on leisure-time physical activity by 13%, but only partially mediated the effect on walking by 4% at 24 weeks.

CONCLUSION: An mHealth intervention involving text messaging and Internet support had a positive treatment effect on leisure-time physical activity and walking at 24 weeks, and this effect was likely mediated through changes in self-efficacy. Future trials should examine other potential mediators related to this type of intervention.

The remote exercise monitoring trial for exercise-based cardiac rehabilitation (REMOTE-CR): a randomised controlled trial protocol

BACKGROUND: Exercise is an essential component of contemporary cardiac rehabilitation programs for the secondary prevention of coronary heart disease. Despite the benefits associated with regular exercise, adherence with supervised exercise-based cardiac rehabilitation remains low. Increasingly powerful mobile technologies, such as smartphones and wireless physiological sensors, may extend the capability of exercise-based cardiac rehabilitation by enabling real-time exercise monitoring for those with coronary heart disease. This study compares the effectiveness of technology-assisted, home-based, remote monitored exercise-based cardiac rehabilitation (REMOTE) to standard supervised exercise-based cardiac rehabilitation in New Zealand adults with a diagnosis of coronary heart disease. METHODS/DESIGN: A two-arm, parallel, non-inferiority, randomised controlled trial will be conducted at two sites in New Zealand. One hundred and sixty two participants will be randomised at a 1:1 ratio to receive a 12-week program of technology-assisted, home-based, remote monitored exercise-based cardiac rehabilitation (intervention), or an 8-12 program of standard supervised exercise-based cardiac rehabilitation (control).The primary outcome is post-treatment maximal oxygen uptake (V̇O2max). Secondary outcomes include cardiovascular risk factors (blood lipid and glucose concentrations, blood pressure, anthropometry), self-efficacy, intentions and motivation to be active, objectively measured physical activity, self-reported leisure time exercise and health-related quality of life. Cost information will also be collected to compare the two modes of delivery. All outcomes are assessed at baseline, post-treatment, and 6 months, except for V̇O2max, blood lipid and glucose concentrations, which are assessed at baseline and post-treatment only. DISCUSSION: This novel study will compare the effectiveness of technology-supported exercise-based cardiac rehabilitation to a traditional supervised approach. If the REMOTE program proves to be as effective as traditional cardiac rehabilitation, it has potential to augment current practice by increasing access for those who cannot utilise existing services. TRIAL REGISTRATION: Australian New Zealand Clinical Trials RegistryStudy ID number: ACTRN12614000843651. Registered 7 August 2014.

Remotely delivered exercise-based cardiac rehabilitation: design and content development of a novel mHealth platform

BACKGROUND: Participation in traditional center-based cardiac rehabilitation exercise programs (exCR) is limited by accessibility barriers. Mobile health (mHealth) technologies can overcome these barriers while preserving critical attributes of center-based exCR monitoring and coaching, but these opportunities have not yet been capitalized on.

OBJECTIVE: We aimed to design and develop an evidence- and theory-based mHealth platform for remote delivery of exCR to any geographical location.

METHODS: An iterative process was used to design and develop an evidence- and theory-based mHealth platform (REMOTE-CR) that provides real-time remote exercise monitoring and coaching, behavior change education, and social support.

RESULTS: The REMOTE-CR platform comprises a commercially available smartphone and wearable sensor, custom smartphone and Web-based applications (apps), and a custom middleware. The platform allows exCR specialists to monitor patients' exercise and provide individualized coaching in real-time, from almost any location, and provide behavior change education and social support. Intervention content incorporates Social Cognitive Theory, Self-determination Theory, and a taxonomy of behavior change techniques. Exercise components are based on guidelines for clinical exercise prescription.

CONCLUSIONS: The REMOTE-CR platform extends the capabilities of previous telehealth exCR platforms and narrows the gap between existing center- and home-based exCR services. REMOTE-CR can complement center-based exCR by providing an alternative option for patients whose needs are not being met. Remotely monitored exCR may be more cost-effective than establishing additional center-based programs. The effectiveness and acceptability of REMOTE-CR are now being evaluated in a noninferiority randomized controlled trial.

How do customers of a financial services institution judge its communications

Communications are important for relationships within a marketing channel from both a theoretical and managerial perspective. Yet it is a problematic area for scholars. Thus, this research addresses the problem of how do customers of a financial services institution perceive communications with an ideal institution? This study's case research methodology used in-depth interviews with 34 carefully selected customers of a building society. The factors that make up customers' attitudes about corporate communications for an ideal financial services institution were identified and actual perceptions were compared against that ideal. The findings confirmed the importance of communications for customers in a relationship with a financial services provider and suggested communication priorities for customers in this context. In addition, the findings suggested sources of communication dissatisfaction for customers. These findings build upon the literature that speculates about customer perceptions of communications with organizations but provides little evidence to support hypotheses. The contributions arose from the emphasis on the customers' own attitudes and the patterns found within them.