Barriers to participation in cardiac rehabilitation in Malta

Cardiovascular disease is the leading cause of death and morbidity worldwide. Patients who have had a cardiac event require special attention to regain their quality of life and to maintain and improve their functional capacity; which could be achieved through cardiac rehabilitation. Literature is continuously showing that cardiac rehabilitation needs to be recognised as part of the treatment to cardiovascular disease, as it is beneficial to the patient’s health. It reduces morbidity and mortality, improves exercise capacity, and through education enables the patient to adhere to lifestyle changes. Despite its proven benefits, cardiac rehabilitation participation remains low globally. Primarily, lack of knowledge and understanding of the importance of lifestyle changes and maintaining a balanced diet might hinder participation. Gender, age and level of education also plays a role in enrolling in the programme. Timing of cardiac rehabilitation also affects the patient’s decision to attend for rehabilitation. Early referral, especially during the patient’s hospitalisation by healthcare professionals, particularly doctors, is recommended to improve uptake to cardiac rehabilitation. Encouragement by staff enables the patients more to participate in such programme. Further research is recommended to identify the barriers which patients find in attending cardiac rehabilitation. Research should also focus on preventive cardiology programmes which should be easily accessible by all hospitals worldwide

An echocardiographic comparison of sutureless and conventional aortic valve replacement : a matched case-control study

Background: Patients at a high operative risk for conventional aortic valve replacement (AVR) may be offered sutureless valve implantation. Sutureless valves resemble conventional valves but incorporate an anchoring mechanism without using annular sutures. Methods Pre-operative and six month post-operative echocardiography data from our first year, single centre experience of sutureless valves was compared to conventional aortic valve replacements in patients matched for operative risk. Left ventricular ejection fraction, mean and peak AV gradients and inter-ventricular septal thickness, effective orifice area (EOA) and indexed effective orifice area (iEOA) were measured. Results The drops in mean and peak pre- to post-operative gradients were greater in the sutureless group, p=0.039 and p=0.001 respectively. Post-operative EOA was 1.69 cm2 and 1.26 cm2 (p=0.001) in the sutureless and conventional groups. Similarly iEOA was 0.93 cm2 and 0.74 cm2 (p=0.001) in the sutureless and conventional groups. There was also a reduction in patient prosthesis mismatch (PPM) in the sutureless group as compared to the conventional group (Chi square test p=0.026). Post-operative inter-ventricular septal thickness was 1.13 cm2 in the sutureless group and 1.35 cm2 in the conventional group (p=0.011). Conclusions Use of sutureless valves with a stent framework resulted in larger EOA and iEOA and a diminution in PPM; and lead to a statistically significant faster regression in inter-ventricular septal thickness that is a measure of left ventricular mass. The rate and extent of regression in left ventricular hypertrophy after AVR is important since it determines long-term survival including mortality, heart failure and decreased admission rates.peer-reviewe

The family and substance abuse among Maltese university students

This study examines how family structure and functioning impact on prevalence and frequency of substance use in late adolescence and emerging adulthood in Malta. Research participants are a convenience sample of 1130 University of Malta students aged between eighteen and twenty-five. Data was collected by means of a structured questionnaire exploring relationships between family functioning, family structure and substance use. The confidence interval for all results is 95% and the study has a maximum margin of error of 2.7%. The study explored the relationship between perceived family intactness, family size, emotional climate, parenting styles, family rituals and monitoring and supervision and patterns of self reported substance use. The results reveal significant relationships between perceived family functioning and family structural variables and self reported substance use especially for family intactness and monitoring and supervision. While the results do not allow for any interpretation regarding causality, they present novel data for the Maltese islands. Recommendations for policy development and further research are explored.peer-reviewe

Reply to Losanoff et al.

Replying to a letter by Losanoff et al.peer-reviewe

Reply to Jutley et al.

Reply to a letter by Jutley et al.peer-reviewe

Pathophysiological mechanism of post-lobectomy air leaks

Background: Air leak post-lobectomy continues to remain a significant clinical problem, with upper lobectomy associated with higher air leak rates. This paper investigated the pathophysiological role of pleural stress in the development of post-lobectomy air leak.Methods: Preoperative characteristics and postoperative data from 367 consecutive video assisted thoracic surgery (VATS) lobectomy resections from one centre were collected prospectively between January 2014 and March 2017. Computer modelling of a lung model using finite element analysis (FEA) was used to calculate pleural stress in differing areas of the lung.Results: Air leak following upper lobectomy was significantly higher than after middle or lower lobectomy (6.3% versus 2.5%, P=0.044), resulting in a significant six-day increase in mean hospital stay, P=0.004. The computer simulation model of the lung showed that an apical bullet shape was subject to eightyfold higher stress than the base of the lung model.Conclusions: After upper lobectomy, the bullet shape of the apex of the exposed lower lobe was associated with high pleural stress, and a reduction in mechanical support by the chest wall to the visceral pleura due to initial post-op lack of chest wall confluence. It is suggested that such higher stress in the lower lobe apex explains the higher parenchymal air leak post-upper lobectomy. The pleural stress model also accounts for the higher incidence of right-sided prolonged air leak post-resection.peer-reviewe

A novel method of personnel cooling in an operating theatre environment

Funding obtained from University of Malta.An optimized theatre environment, including personal temperature regulation, can help maintain concentration, extend work times and may improve surgical outcomes. However, devices, such as cooling vests, are bulky and may impair the surgeon's mobility. We describe the use of a low-cost, low-energy 'bladeless fan' as a personal cooling device. The safety profile of this device was investigated by testing air quality using 0.5- and 5-µm particle counts as well as airborne bacterial counts on an operating table simulating a wound in a thoracic operation in a busy theatre environment. Particle and bacterial counts were obtained with both an empty and full theatre, with and without the 'bladeless fan'. The use of the 'bladeless fan' within the operating theatre during the simulated operation led to a minor, not statistically significant, lowering of both the particle and bacterial counts. In conclusion, the 'bladeless fan' is a safe, effective, low-cost and low-energy consumption solution for personnel cooling in a theatre environment that maintains the clean room conditions of the operating theatre.peer-reviewe

Placement of trans-sternal wires according to an ellipsoid pressure vessel model of sternal forces

Funding from the University of Malta Medical School (Grant IMF/014/11) and University of Malta Research Fund (Grant 31/389/10) is gratefully acknowledged.Dehiscence of median sternotomy wounds remains a clinical problem. Wall forces in thin-walled pressure vessels can be calculated by membrane stress theory. An ellipsoid pressure vessel model of sternal forces is presented together with its application for optimal wire placement in the sternum. Sternal forces were calculated by computational simulation using an ellipsoid chest wall model. Sternal forces were correlated with different sternal thicknesses and radio-density as measured by computerized tomography (CT) scans of the sternum. A comparison of alternative placement of trans-sternal wires located either at the levels of the costal cartilages or the intercostal spaces was made. The ellipsoid pressure vessel model shows that higher levels of stress are operative at increasing chest diameter (P < 0.001). CT scans show that the thickness of the sternal body is on average 3 mm and 30% thicker (P < 0.001) and 53% more radio-dense (P < 0.001) at the costal cartilage levels when compared with adjacent intercostal spaces. This results in a decrease of average sternal stress from 438 kPa at the intercostal space level to 338 kPa at the costal cartilage level (P = 0.003). Biomechanical modelling suggests that placement of trans-sternal wires at the thicker bone and more radio-dense level of the costal cartilages will result in reduced stress.peer-reviewe

Mechanism of sternotomy dehiscence

Research funded by the University of Malta.OBJECTIVES Biomechanical modelling of the forces acting on a median sternotomy can explain the mechanism of sternotomy dehiscence, leading to improved closure techniques. METHODS Chest wall forces on 40 kPa coughing were measured using a novel finite element analysis (FEA) ellipsoid chest model, based on average measurements of eight adult male thoracic computerized tomography (CT) scans, with Pearson's correlation coefficient used to assess the anatomical accuracy. Another FEA model was constructed representing the barrel chest of chronic obstructive pulmonary disease (COPD) patients. Six, seven and eight trans-sternal and figure-of-eight closures were tested against both FEA models. RESULTS Comparison between chest wall measurements from CT data and the normal ellipsoid FEA model showed an accurate fit (P < 0.001, correlation coefficients: coronal r = 0.998, sagittal r = 0.991). Coughing caused rotational moments of 92 Nm, pivoting at the suprasternal notch for the normal FEA model, rising to 118 Nm in the COPD model (t-test, P < 0.001). The threshold for dehiscence was 84 Nm with a six-sternal-wire closure, 107 Nm with seven wires, 127 Nm with eight wires and 71 Nm for three figure-of-eights. CONCLUSIONS The normal rib cage closely fits the ellipsoid FEA model. Lateral chest wall forces were significantly higher in the barrel-shaped chest. Rotational moments generated by forces acting on a six-sternal-wire closure at the suprasternal notch were sufficient to cause lateral distraction pivoting at the top of the manubrium. The six-sternal-wire closure may be successfully enhanced by the addition of one or two extra wires at the lower end of the sternotomy, depending on chest wall shape.peer-reviewe