Showing papers by "London Bridge Hospital published in 2015"

Impact of steerable sheaths on contact forces and reconnection sites in ablation for persistent atrial fibrillation.

Abstract: Steerable Sheaths and Contact Force in AF AblationBackground In preclinical studies, catheter contact force (CF) during radiofrequency ablation correlates with the subsequent lesion size. We investigated the impact of steerable sheaths on ablation CF, its consistency, and wide area circumferential ablation (WACA) line reconnection sites. Methods and Results Five thousand and sixty-four ablations were analyzed across 60 patients undergoing first-time ablation for persistent AF using a CF-sensing catheter: 19 manual nonsteerable sheath (Manual-NSS), 11 manual steerable sheath, and 30 robotic steerable sheath (Sensei, Hansen Medical Inc.) procedures were studied. Ablation CFs were higher in the steerable sheath groups for all left atrial ablations and also WACA ablations specifically (P < 0.006), but less consistent per WACA segment (P < 0.005). There were significant differences in the CFs around both WACAs by group: in the left WACA CFs were lower with Manual-NSS, other than at the anterior–inferior and posterior–superior regions, and lower in the right WACA, other than the anterior–superior region. There was a difference in the proportion of segments chronically reconnecting across groups: Manual-NSS 26.5%, manual steerable sheath 4.6%, robotic 12% (P < 0.0005). The left atrial appendage/PV ridge and right posterior wall were common sites of reconnection in all groups. Conclusions Steerable sheaths increased ablation CF; however, there were region-specific heterogeneities in the extent of increment, with some segments where they failed to increase CF. Steerable sheath use was associated with reduced WACA-segment reconnection. It may be that the benefits of steerable sheath use in terms of higher CFs could be translated to improved clinical outcomes if regional weaknesses of this technology are taken into account during ablation procedures.

Cardiopulmonary exercise testing versus spirometry as predictors of cardiopulmonary complications after colorectal surgery

Abstract: To determine the predictive value of spirometry and cardiopulmonary exercise testing (CPET) preoperatively in patients scheduled to undergo elective colorectal surgery. We compared the preoperative results with the incidence of postoperative cardiopulmonary complications. A total of 103 patients were scheduled to undergo preoperative CPET and spirometry; 14 patients did not attend their appointments and another 20 were unable to perform the test. In all, 69 patients (median age 60 years (range 25–85), 35 males) successfully completed cycle ergometry and lung function tests. Forced expiratory volume in 1 s (FEV1), percent forced expiratory volume in 1 s (FEV1/forced vital capacity (FVC)) and anaerobic threshold (AT) were measured. Patients were divided postoperatively according to whether cardiopulmonary complications were absent (group A) or present (group B). Postoperative cardiopulmonary complications developed in 8 of the 69 patients (12 %). Thirty day mortality was 3 %. AT was significantly higher in group A (mean AT = 13.8; SD ± 3.0; range = 8.1–20.8) than in group B (mean = 10.91; SD ± 3.0; Range = 7.9–12), (p = 0.0006). Spirometric pulmonary function tests (FEV1, p = 0.09) and (FEV1/FVC, p = 0.08) showed no intergroup differences. The median hospital length of stay (HLOS) was significantly higher in the group of patients that suffered cardiopulmonary complications (p = 0.0282). CPET allows the prediction of postoperative cardiopulmonary complications which cannot be anticipated by spirometry. Early detection of high risk patients facilitates the planning of patient specific management strategies which are likely to improve outcome through invasive monitoring and optimisation of cardio-respiratory function.

Lupus around the world

Abstract: Back in 1970, when I was a post-doc fellow in the unit of Dr Charles Christian in New York, I remember seeing a fairly primitive ‘world map’ of units which had published 200 lupus cases or more. As I recall, there were few ‘dots’ on the map—indeed there were huge swathes of the globe where lupus failed to ‘light up’. So much has changed, with lupus becoming an increasingly common diagnosis worldwide. In some countries, for example in the Far East, lupus may well have overtaken rheumatoid arthritis in prevalence. In 1995, we launched, in this journal, a series called ‘Lupus around the world’, in order firstly to compare prevalence and disease patterns in different regions, and secondly to facilitate publication of data from centres with solid experience of the disease, but with little international publishing success. A trawl through the 100 or so articles in this series does seem to underscore this trend. The numbers are striking, including a series of 2684 patients from China, 9349 from Taiwan, (also from Taiwan a staggering series of 2870 admitted to intensive care over a period of nine years),1521 from Korea, 841 from Singapore, and 428 from two centres in Turkey. There were of course, similarities—the almost universal 9:1 female to male ratio—and differences between the series. Ethnic differences were frequently reported, such as the higher prevalence in Kazakhstan (predominantly ethnic Asian) in the large Russian survey. An Australian survey found a prevalence of 95 per 100,000 in the indigenous peoples compared with 45 per 100,000 in the non-indigenous population. In addition, with this higher prevalence in certain ethnic groups, there was frequent evidence of more serious disease. For example, in a study of patients attending two hospitals in New Zealand, 60% of the Maori patients developed renal disease compared with 19% of Caucasians. A number of studies addressed possible lifestyle and local factors. In Kuwait, where up to 44.8% of marriages are consanguineous, ‘we found that familial and sporadic cases of SLE [systemic lupus erythematosus] are broadly similar . . .’. There is a report from Brazil of a high incidence of lupus in Natal City—also known as ‘sun city’ with up to 288 hours of sun a month. In addition, there are interesting studies of Malaviya and colleagues who found a similar prevalence of antiphospholipid antibodies in New Delhi Indians and Arab Kuwaitis, but with a far higher incidence of thrombotic antiphospholipid syndrome in the Kuwaitis. Many of the studies reported clinical differences—the highest incidence of infections were in the Brazilian and Saudi populations. Another Saudi report documented a high percentage (82%) of haematological abnormalities, and Edwards in Singapore noted the frequency of gastro-intestinal problems in that particular series. Two of the studies reported on the lack of association between lupus and cancer. 20 There were some laboratory associations of interest: Uthman et al. in Beirut found 25% of their series with false positive VDRL tests, and pulmonary hypertension strongly associated with positive anti-Beta2 GP1 antibodies in a report from Tunisia. Perhaps the most recurring epidemiological observation is the seeming rarity of lupus in Africans living in Africa, compared with its high prevalence in African–Americans and West Indians. In our own studies in Jamaica, back in 1975, lupus was the second most common rheumatological hospital admission (after rheumatic fever). 24 The studies of Gilkeson et al. and Barnado et al. comparing genetics and disease manifestations in the ‘Gullah Indians’ of South Carolina, and their close relatives in Sierra Correspondence to: GRV Hughes, London Lupus Centre, London Bridge Hospital, Tooley Street, London SE1 2PR, UK. Email: Graham.Hughes@HCAConsultant.co.uk Received 30 April 2015; accepted 30 April 2015