Pacing with capture verification in candidates for resynchronisation therapy: a feasibility study.

BACKGROUND: Devices for cardiac resynchronisation therapy (CRT) deliver energy into 3 output channels. Such a burden can significantly reduce device longevity. Autocapture has been shown to improve pacemaker longevity and safety of right ventricular pacing in clinical studies. The aim of this study was to investigate the application of Autocapture during biventricular pacing (BIV) to decrease the energy cost of CRT. METHODS: During implantation of BIV devices, an acute study was performed to test the hypothesis that the evoked response (ER) elicited by each delivered stimulus is correctly detected and measured either on the right ventricular (RV) channel during BIV pacing with the left ventricular (LV) channel pacing first, or in the LV channel with the RV channel pacing first. A reliable measurement of ER is the critical requirement for the correct performance of Autocapture. RESULTS: ER amplitude in the right ventricle during BIV pacing was not significantly decreased compared with RV pacing in the VVI mode (16.36+/-5.27 mV vs 17.09+/-6.12 mV). ER amplitude in the left ventricle during BIV pacing was not significantly decreased compared with LV pacing in the VVI mode (12.4+/-8.95 mV vs 12.25+/-8.97 mV). Three patients in atrial fibrillation had a DDDR pacemaker with the LV lead connected to the atrial port, and received BIV pacing with Autocapture turned on in the RV channel. Autocapture performance in the long term, as assessed by the trend of RV threshold over 20+/-8 months, showed that LV depolarisation was never sensed as an ER on the RV channel. CONCLUSIONS: Our observations support the feasibility and safety of capture verification during BIV pacing on the ventricular channel paced secondly, which could increase the longevity of CRT devices, and decrease the costs of this new therapy for heart failure patients.     

Interleukin-21 combined with ART reduces inflammation and viral reservoir in SIV-infected macaques

Despite successful control of viremia, many HIV-infected individuals given antiretroviral therapy (ART) exhibit residual inflammation, which is associated with non–AIDS-related morbidity and mortality and may contribute to virus persistence during ART. Here, we investigated the effects of IL-21 administration on both inflammation and virus persistence in ART-treated, SIV-infected rhesus macaques (RMs). Compared with SIV-infected animals only given ART, SIV-infected RMs given both ART and IL-21 showed improved restoration of intestinal Th17 and Th22 cells and a more effective reduction of immune activation in blood and intestinal mucosa, with the latter maintained through 8 months after ART interruption. Additionally, IL-21, in combination with ART, was associated with reduced levels of SIV RNA in plasma and decreased CD4⁺ T cell levels harboring replication-competent virus during ART. At the latest experimental time points, which were up to 8 months after ART interruption, plasma viremia and cell-associated SIV DNA levels remained substantially lower than those before ART initiation in IL-21–treated animals but not in controls. Together, these data suggest that IL-21 supplementation of ART reduces residual inflammation and virus persistence in a relevant model of lentiviral disease and warrants further investigation as a potential intervention for HIV infection.     

Laparoscopic management of intra-abdominal infections: Systematic review of the literature

AIM: To investigate the role of laparoscopy in diagnosis and treatment of intra abdominal infections.METHODS: A systematic review of the literature was performed including studies where intra abdominal infections were treated laparoscopically.RESULTS: Early laparoscopic approaches have become the standard surgical technique for treating acute cholecystitis. The laparoscopic appendectomy has been demonstrated to be superior to open surgery in acute appendicitis. In the event of diverticulitis, laparoscopic resections have proven to be safe and effective procedures for experienced laparoscopic surgeons and may be performed without adversely affecting morbidity and mortality rates. However laparoscopic resection has not been accepted by the medical community as the primary treatment of choice. In high-risk patients, laparoscopic approach may be used for exploration or peritoneal lavage and drainage. The successful laparoscopic repair of perforated peptic ulcers for experienced surgeons, is demonstrated to be safe and effective. Regarding small bowel perforations, comparative studies contrasting open and laparoscopic surgeries have not yet been conducted. Successful laparoscopic resections addressing iatrogenic colonic perforation have been reported despite a lack of literature-based evidence supporting such procedures. In post-operative infections, laparoscopic approaches may be useful in preventing diagnostic delay and controlling the source.CONCLUSION: Laparoscopy has a good diagnostic accuracy and enables to better identify the causative pathology; laparoscopy may be recommended for the treatment of many intra-abdominal infections.     

Abscess of residual lobe after pulmonary resection for lung cancer

Abscess of the residual lobe after lobectomy is a rare but potentially lethal complication. Between January 1975 and December 2006, 1,460 patients underwent elective pulmonary lobectomy for non-small-cell lung cancer at our institution. Abscess of the residual lung parenchyma occurred in 5 (0.3%) cases (4 bilobectomies and 1 lobectomy). Postoperative chest radiography showed incomplete expansion and consolidation of residual lung parenchyma. Flexible bronchoscopy revealed persistent bronchial occlusion from purulent secretions and/or bronchial collapse. Computed tomography in 3 patients demonstrated lung abscess foci. Surgical treatment included completion right pneumonectomy in 3 patients and a middle lobectomy in one. Complications after repeat thoracotomy comprised contralateral pneumonia and sepsis in 1 patient. Residual lobar abscess after lobectomy should be suspected in patients presenting with fever, leukocytosis, bronchial obstruction and lung consolidation despite antibiotic therapy, physiotherapy and bronchoscopy. Computed tomography is mandatory for early diagnosis. Surgical resection of the affected lobe is recommended.     

Implications of cardiac resynchronization therapy and prophylactic defibrillator implantation among patients eligible for heart transplantation

This study analyzed the relations and time-related changes in eligibility for cardiac resynchronization therapy and prophylactic defibrillator implantation in 161 potential candidates for heart transplantation. Although up to 62% of patients who fulfilled the severity criteria for heart transplantation were eligible for either device, this percentage increased as clinical/instrumental parameters of heart failure severity worsened.     

Glutathione S-transferase P1 and lung function in patients with alpha1-antitrypsin deficiency and COPD

BACKGROUND: The glutathione S-transferase P1 (GSTP1) gene is involved in detoxification of electrophilic substances of tobacco smoke. A polymorphism at nucleotide 315 of this gene alters its enzymatic activity. OBJECTIVE: We analyzed the association between the variability in the GSTP1 gene and impairment in lung function in smokers with and without alpha(1)-antitrypsin (AAT) deficiency and COPD.Population and method: The study population consisted of 99 patients with smoking-related COPD and 69 patients with AAT deficiency; 198 healthy volunteers provided the frequency of the different polymorphisms in the general population. GSTP1 genotyping was performed by a real-time polymerase chain reaction amplification assay. RESULTS: The frequency (0.28) of the 105Val polymorphism was identical in COPD patients and the general population. However, the frequency was significantly increased (0.44) in patients with AAT deficiency (odds ratio [OR], 2.09; 95% confidence interval [CI], 1.17 to 3.72 compared to control subjects; and OR, 2.41; 95% CI, 1.27 to 4.59 compared to COPD). FEV(1) percentage of predicted was significantly impaired in AAT-deficient carriers of 105Val. This effect was not observed in COPD patients. CONCLUSIONS: These findings suggest that the frequency of the GSTP1 105Val polymorphism is increased in patients with AAT deficiency. Globally, GSTP1 genotypes, age, and tobacco smoking explained 41% of total FEV(1) percentage of predicted variability in patients with AAT deficiency. The modulatory role of GSTP1 in lung disease has only been observed in smokers lacking AAT.