A single-centre prospective evaluation of left bundle branch area pacemaker implantation characteristics.

BACKGROUND: Left bundle branch area pacing (LBBAP) has recently been introduced as a physiological pacing technique with synchronous left ventricular activation. It was our aim to evaluate the feasibility and learning curve of the technique, as well as the electrical characteristics of LBBAP. METHODS AND RESULTS: LBBAP was attempted in 80 consecutive patients and electrocardiographic characteristics were evaluated during intrinsic rhythm, right ventricular septum pacing (RVSP) and LBBAP. Permanent lead implantation was successful in 77 of 80 patients (96%). LBBAP lead implantation time and fluoroscopy time shortened significantly from 33 ± 16 and 21 ± 13 min to 17 ± 5 and 12 ± 7 min, respectively, from the first 20 to the last 20 patients. Left bundle branch (LBB) capture was achieved in 54 of 80 patients (68%). In 36 of 45 patients (80%) with intact atrioventricular conduction and narrow QRS, an LBB potential (LBBpot) was present with an LBBpot to onset of QRS interval of 22 ± 6 ms. QRS duration increased significantly more during RVSP (141 ± 20 ms) than during LBBAP (125 ± 19 ms), compared to 130 ± 30 ms without pacing. An even clearer difference was observed for QRS area, which increased significantly more during RVSP (from 32 ± 16 µVs to 73 ± 20 µVs) than during LBBAP (41 ± 15 µVs). QRS area was significantly smaller in patients with LBB capture compared to patients without LBB capture (43 ± 18 µVs vs 54 ± 21 µVs, respectively). In patients with LBB capture (n = 54), the interval from the pacing stimulus to R­wave peak time in lead V6 was significantly shorter than in patients without LBB capture (75 ± 14 vs 88 ± 9 ms, respectively). CONCLUSION: LBBAP is a safe and feasible technique, with a clear learning curve that seems to flatten after 40-60 implantations. LBB capture is achieved in two-thirds of patients. Compared to RVSP, LBBAP largely maintains ventricular electrical synchrony at a level close to intrinsic (narrow QRS) rhythm.

Clinical determinants of early spontaneous conversion to sinus rhythm in patients with atrial fibrillation.

BACKGROUND: The current standard of care for acute atrial fibrillation (AF) focuses primarily on immediate restoration of sinus rhythm by cardioversion, although AF often terminates spontaneously. OBJECTIVE: To identify determinants of early spontaneous conversion (SCV) in patients presenting at the emergency department (ED) because of AF. METHODS: An observational study was performed of patients who visited the ED with documented AF between July 2014 and December 2016. The clinical characteristics and demographics of patients with and without SCV were compared. RESULTS: We enrolled 943 patients (age 69 ± 12 years, 47% female). SCV occurred within 3 h of presentation in 158 patients (16.8%). Logistic regression analysis showed that duration of AF <24 h [odds ratio (OR) 7.7, 95% confidence interval (CI) 3.5-17.2, p < 0.001], left atrial volume index <42 ml/m2 (OR 1.8, 95% CI 1.2-2.8, p = 0.010), symptoms of near-collapse at presentation (OR 2.4, 95% CI 1.2-5.1, p = 0.018), a lower body mass index (BMI) (OR 0.9, 95% CI 0.91-0.99, p = 0.028), a longer QTc time during AF (OR 1.01, 95% CI 1.0-1.02, p = 0.002) and first-detected AF (OR 2.5, 95% CI 1.6-3.9, p < 0.001) were independent determinants of early SCV. CONCLUSION: Early spontaneous conversion of acute AF occurs in almost one-sixth of admitted patients during a short initial observation in the ED. Spontaneous conversion is most likely to occur in patients with first-onset, short-duration AF episodes, lower BMI, and normal left atrial size.

Low resting heart rates are associated with new-onset atrial fibrillation in patients with vascular disease: results of the ONTARGET/TRANSCEND studies.

BACKGROUND: Elevated systolic blood pressure (SBP) and high resting heart rate (HR) are associated with cardiovascular end-points. Although the association between atrial fibrillation (AF) and SBP is well established, the relation between AF and HR remains unclear. METHODS: In patients from the ONTARGET and TRANSCEND studies with high cardiovascular disease risk (n = 27 064), new-onset AF was evaluated in relation to mean SBP, visit-to-visit variation in SBP (SBP-CV; i.e. SD/mean × 100%), mean HR and visit-to-visit variation in HR (HR-CV). RESULTS: Low mean HR (P < 0.0001) and high SBP (P = 0.0021) were associated with incident AF. High SBP-CV (P = 0.031) and HR-CV (P < 0.0001) were also associated with incident AF. After adjustment for confounders, SBP and SBP-CV were no longer significantly associated with AF. The detrimental effect of low HR was particularly evident in subjects who were not receiving treatment with beta-blockers (P = 0.014 for interaction between beta-blocker use and mean HR). In addition to low HR, high HR-CV and high SBP had additive effects on incident AF. CONCLUSIONS: Low mean HR (<60 beats min(-1) ) is independently associated with incident AF, and low HR-CV and high SBP further increase the incidence of new-onset AF in patients at high risk of cardiovascular disease.

Resting heart rate is associated with renal disease outcomes in patients with vascular disease: results of the ONTARGET and TRANSCEND studies.

BACKGROUND: Resting heart rate (RHR) is associated with cardiovascular disease outcomes in high-risk patients. It is not known whether RHR is predictive of renal outcomes such as albuminuria, end-stage renal disease (ESRD) or doubling of creatinine. We evaluated whether RHR could predict renal endpoints in patients at a high risk of cardiovascular disease. We also tested the effects of RHR at different levels of systolic blood pressure (SBP). METHODS: We analysed data from 28 757 patients in the ONTARGET and TRANSCEND trials. RHR and SBP were available for a mean of 4.9 ± 0.4 visits (range 3-5) within the first 2 years of the studies. Albuminuria was determined at baseline, at 2 years and at study end. RESULTS: Mean RHR was predictive of incident micro-albuminuria [hazard ratio (HR) for RHR ≥80 vs. <60 beats min(-1) 1.49, 95% confidence interval (CI) 1.29-1.71, P < 0.0001], incident macro-albuminuria (HR 1.84, 95% CI 1.39-2.42, P < 0.0001), doubling of creatinine (HR 1.47, 95% CI 1.00-2.17, P = 0.050) and ESRD (HR 1.78, 95% CI 1.00-3.16, P = 0.050), and the combined renal end-point (HR 1.51, 95% CI 1.32-1.74, P < 0.0001). Associations were robust at SBPs from <120 to ≥150 mmHg, with the lowest risk at a SBP of 130-140 mmHg. CONCLUSION: Resting heart rate is a potent predictor of these renal outcomes, as well as their combination, in patients with cardiovascular disease. RHR at all SBP levels should be considered as a possible renal disease risk predictor and should be investigated as a treatment target with RHR-reducing agents.

[Interventional hypertension therapy in diabetes mellitus. Effects on blood pressure and glucose metabolism?]. / Interventionelle Hypertonietherapie bei Diabetes mellitus. Effekte auf Blutdruck und Glukosestoffwechsel?

Hypertension is the most common chronic cardiovascular disease with increasing prevalence all over the world. Despite the availability of many effective antihypertensive drugs, blood pressure control to target values remains low. In the pathophysiology of therapy resistant hypertension, increased activity of the sympathetic nervous system with an imbalance between sympathetic and parasympathetic activity has been identified as a main contributor to the development and maintenance of hypertension. Catheter-based denervation of the renal sympathetic nerves has been described as reducing blood pressure and decreasing sympathetic activity in patients with resistant hypertension. Supplementary beneficial effects on common cardiovascular comorbidities, such as diabetes type 2, have been reported. The present review aims to give an overview about percutaneous renal denervation for treatment of hypertension and potential new therapeutic options to improve glycemic control.

Structural and electro-anatomical characterization of the equine pulmonary veins: implications for atrial fibrillation.

INTRODUCTION/OBJECTIVES: Spontaneous pulmonary vein (PV) activity triggers atrial fibrillation (AF) in humans. Although AF frequently occurs in horses, the origin remains unknown. This study investigated the structural and electro-anatomical properties of equine PVs to determine the potential presence of an arrhythmogenic substrate. ANIMALS, MATERIALS AND METHODS: Endocardial three-dimensional electro-anatomical mapping (EnSite Precision) using high-density (HD) catheters was performed in 13 sedated horses in sinus rhythm. Left atrium (LA) access was obtained retrogradely through the carotid artery. Post-mortem, tissue was harvested from the LA, right atrium (RA), and PVs for histological characterization and quantification of ion channel expression using immunohistochemical analysis. RESULTS: Geometry, activation maps, and voltage maps of the PVs were created and a median of four ostia were identified. Areas of reduced conduction were found at the veno-atrial junction. The mean myocardial sleeve length varied from 28 ± 13 to 49 ± 22 mm. The PV voltage was 1.2 ± 1.4 mV and lower than the LA (3.4 ± 0.9 mV, P < 0.001). The fibrosis percentage was higher in PV myocardium (26.1 ± 6.6%) than LA (14.5 ± 5.0%, P = 0.003). L-type calcium channel (CaV1.2) expression was higher in PVs than LA (P = 0.001). T-type calcium channels (CaV3.3), connexin-43, ryanodine receptor-2, and small conductance calcium-activated potassium channel-3 was expressed in PVs. CONCLUSIONS: The veno-atrial junction had lower voltages, increased structural heterogeneity and areas of slower conduction. Myocardial sleeves had variable lengths, and a different ion channel expression compared to the atria. Heterogeneous properties of the PVs interacting with the adjacent LA likely provide the milieu for re-entry and AF initiation.

Tissue characterization of acute lesions during cardiac magnetic resonance-guided ablation of cavo-tricuspid isthmus-dependent atrial flutter: a feasibility study.

AIMS: To characterize acute lesions during cardiac magnetic resonance (CMR)-guided radiofrequency (RF) ablation of cavo-tricuspid isthmus (CTI)-dependent atrial flutter by combining T2-weighted imaging (T2WI), T1 mapping, first-pass perfusion, and late gadolinium enhancement (LGE) imaging. CMR-guided catheter ablation offers a unique opportunity to investigate acute ablation lesions. Until present, studies only used T2WI and LGE CMR to assess acute lesions. METHODS AND RESULTS: Fifteen patients with CTI-dependent atrial flutter scheduled for CMR-guided RF ablation were prospectively enrolled. Directly after achieving bidirectional block of the CTI line, CMR imaging was performed using: T2WI (n = 15), T1 mapping (n = 10), first-pass perfusion (n = 12), and LGE (n = 12) imaging. In case of acute reconnection, additional RF ablation was performed. In all patients, T2WI demonstrated oedema in the ablation region. Right atrial T1 mapping was feasible and could be analysed with a high inter-observer agreement (r = 0.931, ICC 0.921). The increase in T1 values post-ablation was significantly lower in regions showing acute reconnection compared with regions without reconnection [37 ± 90 ms vs. 115 ± 69 ms (P = 0.014), and 3.9 ± 9.0% vs. 11.1 ± 6.8% (P = 0.022)]. Perfusion defects were present in 12/12 patients. The LGE images demonstrated hyper-enhancement with a central area of hypo-enhancement in 12/12 patients. CONCLUSION: Tissue characterization of acute lesions during CMR-guided CTI-dependent atrial flutter ablation demonstrates oedema, perfusion defects, and necrosis with a core of microvascular damage. Right atrial T1 mapping is feasible, and may identify regions of acute reconnection that require additional RF ablation.

[Heart and kidneys. Renal denervation as therapy for hypertension]. / Herz und Niere. Hochdrucktherapie durch renale Denervation.

Arterial hypertension is a major cardiovascular risk factor with a high prevalence in western industrial countries and the proportion of patients with blood pressure at target values remains low. Patients with therapy-resistant hypertension, defined as failure to achieve target blood pressure despite a triple antihypertensive drug regimen including a diuretic, are at very high risk which supports the need for greater efforts towards improving hypertension outcomes in this population. Secondary causes of hypertension are often found in patients with resistant hypertension. Activation of the sympathetic nervous system has been identified as a main contributor to the development and progression of high blood pressure. Catheter-based renal denervation offers a new interventional treatment option resulting in a significant long-term reduction in blood pressure (> 36 months) and increased blood pressure control (up to 40% of the treated population). The basis for successful treatment is an appropriate patient selection, including life-style modification, exclusion of pseudoresistance, termination of substances increasing blood pressure and an optimized drug treatment. Further clinical studies are warranted and ongoing to determine the role of renal denervation in antihypertensive treatment.

Assessing the effects of the Medicare Prospective Payment System on the demand for VA inpatient services: an examination of transfers and discharges of problem patients.

An examination of patient data from three medical districts that vary in urban/rural composition and in their proportion of proprietary hospitals was undertaken to determine if high-cost patients whose illnesses place them in "problem" DRGs (diagnosis-related groups identified as "problems" through interviews with private hospital administrators and from information published by the Wisconsin Hospital Association) are being shifted from non-Department of Veterans Affairs (non-VA) hospitals to VA hospitals. Two outcome measures were employed to detect shifting: patient transfers between non-VA and VA hospitals and discharges of veterans in a sample of DRGs identified as unprofitable by private hospitals. A comparison of patient transfers for fiscal year 1982 and fiscal year 1984 (pre- and post-DRG implementation) revealed substantial increases in the number of transfers, but there appeared to be no concentration of transfers in particular DRGs. An examination of discharges for FY 1982 and FY 1984 within 21 problem DRGs showed average increases ranging from 27 percent to 41 percent among patients aged 65 years or older. A comparison of discharges within a sample of 21 randomly selected DRGs showed either no increase or small decreases in discharges from FY 1982 to FY 1984. The possibility is discussed that some of the cost reductions (or slowing of the rise in costs) attributed to the prospective payment system are merely phantom savings. Hospitals may simply be shifting costs from Medicare to the VA system.

Desensitization and resensitization to violence against women: effects of exposure to sexually violent films on judgments of domestic violence victims.

An experiment was conducted to examine the effects of repeated exposure to sexually violent films on emotional desensitization and callousness toward domestic abuse victims. Results indicated that emotional response, self-reported physiological arousal, and ratings of the extent to which the films were sexually violent all diminished with repeated film exposure. Three days following exposure to the final film, experimental participants expressed significantly less sympathy for domestic violence victims, and rated their injuries as less severe, than did a no-exposure comparison group. Five days after the final film exposure, their level of sensitivity to the domestic violence victims had rebounded to baseline levels established by the comparison group. Emotional responsiveness at the final film exposure was correlated with levels of sensitivity to the domestic violence victims 3 days later but not at subsequent observation points.

Effects of long-term exposure to violent and sexually degrading depictions of women.

In this study we investigated the effects of emotional desensitization to films of violence against women and the effects of sexually degrading explicit and nonexplicit films on beliefs about rape and the sexual objectification of women. Male subjects viewed either two or five R-rated violent "slasher," X-rated nonviolent "pornographic," or R-rated nonviolent teenage-oriented ("teen sex") films. Affective reactions and cognitive perceptions were measured after each exposure. Later, these men and no-exposure control subjects completed a voir dire questionnaire, viewed a reenacted acquaintance or nonacquaintance sexual assault trial, and judged the defendant and alleged rape victim. Subjects in the violent condition became less anxious and depressed and showed declines in negative affective responses. They were also less sympathetic to the victim and less empathetic toward rape victims in general. However, longer film exposure was necessary to affect general empathy. There were no differences in response between the R-rated teen sex film and the X-rated, sexually explicit, nonviolent film, and the no-exposure control conditions on the objectification or the rape trial variables. A model of desensitization to media violence and the carryover to decision making about victims is proposed.

Using the confluence model of sexual aggression to predict men's conflict with women: a 10-year follow-up study.

We tested a model describing the characteristics of sexually aggressive men that may also be useful for understanding the causes of other antisocial acts against women. This model hypothesizes that sexual aggressors can be identified by two sets of characteristics, labeled hostile masculinity and impersonal sex. To test this model, we followed up a sample of men 10 years after first studying them when they were young adults. We sought to predict which men would be in distressed relationships with women, be aggressive sexually, be nonsexually aggressive, or some combination of these. These behaviors were measured not only by questioning the men themselves but also by questioning many of the men's female partners. Some couples' videotaped conversations were also analyzed. The data supported the ability of the model to predict behavior 10 years later. We also developed the model further and identified the common and unique characteristics contributing to sexual aggression as compared with the other conflictual behaviors studied. The data supported the usefulness of hierarchical modeling incorporating both general factors that contribute to various interpersonal conflicts as well as specific factors uniquely pertaining to dominance of women.

Fracture and embolization of a peripherally inserted central venous catheter.

A case is presented of the fracture and embolization of a peripherally inserted central venous catheter. This novel complication is discussed in the context of patients in alternate care settings with emphasis on retrieval of the embolized catheter fragment, morbidity of catheter embolization, and precautions against inadvertent fracture in the home care setting.

Postural stability assessment in sewer workers.

In this study, postural stability was measured with a microcomputer-based force platform as an indirect assessment of central nervous system effect in 28 sewer workers (age range 23.4 to 64.5 years, standard deviation of 8.7 years). All workers performed four 30-second postural sway tests. The organic-solvent exposure was measured by a photo-ionization detector. The photo-ionization detector was calibrated to measure volatile organic solvents in total benzene equivalence, and concentrations were measured in various parts of the plant. The mean exposure was .32 parts per million (ppm) benzene equivalent (range of .02 to .95 ppm, standard deviation .19 ppm). Based on a covariate adjusted linear multiple-regression model, a statistically significant (p < .05) positive correlation was demonstrated between postural sway and organic-solvent exposure. These workers also had increased postural sway compared with a nonexposed population. The statistically significant correlation between postural sway determinations and organic-solvent exposure was surprising given the very low exposures measured. It is possible that the organic-solvent exposure might not be the causative agent, but rather that the solvents themselves correlate with some other causative exposure, ie, total volatile organics as implicated in the cause of sick-building syndrome.

Disability case management: an impact assessment in an automotive manufacturing organization.

A multifaceted disability management program was instituted at an automotive manufacturing organization to control rising workers' compensation costs. A pilot program showed major cost savings over a 9-month period. When total and component disability leave rates were calculated as a percentage of the available workforce and tracked on a weekly basis over the subsequent 3 years, total disability leave rates fell by nearly 50%. This was largely attributable to an approximately 50% decrease in the extended (> 1-year) disability leave rate and a 75% decrease in the workers' compensation leave rate. A novel approach to biostatistical analysis showed a good fit of weekly disability leave rates to a Poisson random variable distribution with an identifiable break point at about 1 1/2 years after observation for extended disability leaves and at 2 years for workers' compensation leaves. This biostatistical approach may prove generalizable to tracking leave rates in other organizations.

Cluster analysis applied to building-related illness.

Identifying remediable causes of occupant symptoms in building-related illness is frequently difficult. This is particularly true when the building-wide prevalence of symptoms is comparable to that reported in non-problem buildings. This analysis applied an epidemiological approach to an assessment of a problem building, allowing investigators to visually identify an area of apparent increased symptom density. A cluster analysis approach permitted biostatistical confirmation of the visual cluster. Building-related symptom reporting was statistically significantly associated with a prior physician diagnosis of dust and/or mold allergy. The likely etiology of building occupant symptoms was identified within the region implicated by the cluster analysis. This approach may be useful to focus building evaluations on both the likely physical source and general characteristics of suspect etiologic agents.

Care management of work injuries: results of a 1-year pilot outcome assurance program.

A 1-year pilot study was conducted, linking the efforts of a workers' compensation managed care organization with those of an occupational health clinic and emergency department of manage work-related injuries and associated work disability. Sustained (> 90 day), injury-specific return-to-work outcomes, modified by job title, were compared with loosely managed and well-managed benchmarks. The mean return-to-work outcome, measured as lost workdays (LWDs), was 5.11 +/- 21.0 LWDs for 418 workers. These results exceeded benchmarks for both loosely managed care, 14.0 +/- 17.2 LWDs, P < 0.001 (8.9 fewer LWDs/case), and optimally case-managed care, 6.99 +/- 7.64 LWDs, P = 0.044 (1.9 fewer LWDs/case). An estimate of the value of these saved LWDs to the employers-at $200 per workday was $740,400 for the loosely managed benchmarks and $157,000 for the well-managed benchmarks. The Outcome Assurance Program virtually eliminated typical delays in the diagnosis and medical management of these injured workers.

Does the current health care environment contribute to increased morbidity and mortality of acute appendicitis in children?

To determine whether the current "gatekeeper" controls on health care lead to an increase in treatment delay and morbidity of acute appendicitis in children, we reviewed the experience with this disease at a large children's hospital over a 10-year period. One hundred seven consecutive children 18 years and younger operated on for acute appendicitis from July 1, 1988 to June 30, 1990 were compared with 119 children with the same diagnosis from July 1, 1978 to June 30, 1980. Age, sex, race, antecedent illnesses, initial physician contact and diagnosis, time to referral and operation, pathology, morbidity, and length of stay were reviewed. The two groups were comparable in terms of age, sex, race, antecedent illnesses, and negative appendectomy rate. More patients in the recent group were initially seen in an emergency room or urgent care setting than in the previous group (62.2% v 48.5%, P = .07). The accuracy of the initial diagnosis was significantly lower in the more recent group (P = .05). No change existed between the groups in the time to a physician; however, a significant (P = .04) difference existed in the time to surgeon (41.2 hours in the earlier group v 56.4 hours in the recent group). No significant difference existed between the groups in time from surgeon to operation. Although not statistically significant, the morbidity rate was increased in the recent group (13.3% v 6.5%, P = .17).(ABSTRACT TRUNCATED AT 250 WORDS)

Prostaglandin and tumor necrosis factor levels in early wound inflammatory fluid: effects of parenteral omega-3 and omega-6 fatty acid administration.

Monokines are important mediators of wound healing. Specifically, the proportions of proinflammatory (tumor necrosis factor and PGE2) and antiinflammatory (PGF2 alpha) monokines may modulate its early phases. Using a polyvinyl alcohol sponge model of rat wounding, the authors determined the temporal changes in the levels of monokines in wound inflammatory fluid, and examined whether dietary manipulation for 6 days with the precursors (omega 6 fatty acids) and inhibitors (fish oil omega 3 fatty acids) of the prostaglandin-2 series influenced monokine composition of wound fluid. For 3 days before the wounding, adult rats received isocaloric, isovolemic, and isonitrogenous total parenteral nutrition (TPN), in which lipids supplied either 35% (Intralipid [IL] or fish oil emulsion [FO]) or 8% (minimal essential fatty acid; EFA) of the total calories. Control rats received isocaloric enteral chow. The controls were studied at 24, 48, 72, and 96 hours, and the experimentals at 72 hours after wounding. Cell counts were performed, and cell-free fluid was analyzed for PGE2, PGF2 alpha, and TNF. In control rats, the total WBC count was highest at 24 to 48 hours, and decreased significantly by 96 hours. The percentage of mononuclear cells progressively increased throughout the 96 hours, and the total mononuclear cell count peaked at 72 hours. The TNF and prostaglandin levels were highest at 24 hours; these decreased rapidly by 72 hours. At all time-points, the levels of PGE2 remained higher than those of PGF2 alpha.(ABSTRACT TRUNCATED AT 250 WORDS)