P2468Clinical and cardiac structural differences between paroxysmal and persistent/permanent non-valvular atrial fibrillation

Background

Atrial Fibrillation (AF) is a heterogeneous condition and is traditionally classified by duration (paroxysmal, persistent and permanent). There is a relationship between AF and left atrial (LA) remodeling, with increased likelihood of AF recurrence and maintenance with increasing LA volumes.

Purpose

To assess clinical and cardiac structural differences between the subtypes of AF.

Methods

We examined 1247 (68±13.4y; 50% men) consecutive admissions presenting to our institution with the primary diagnosis of AF. Repeat admissions (n=263) were excluded. Of remaining 984 subjects, a majority had diagnosed paroxysmal (72.2%), with lower numbers of persistent (23.4%) and permanent (4.4%) AF. Echo parameters of cardiac chamber size and function were examined in a subset of subjects with complete echo (n=646) performed during incident hospital admission.

Results

There were significantly higher rates of diabetes mellitus (p=0.03), ischaemic heart disease (IHD; p=0.04) and peripheral vascular disease (PVD; p=0.02) in those with persistent/permanent AF compared to paroxysmal AF. No significant differences in age (p=0.19), BMI (p=0.42), OSA (p=0.05), or hypertension (p=0.76) was noted. There were significant differences in left ventricular (LV) mass and systolic function, LA size and function between the two groups (Table 1). Receiver operator curve analysis revealed that LAEF was a discriminator for persistent/permanent AF with an area under the curve of 0.689 (95% CI, 0.646 to 0.732; p<0.001).

Echo parameters in AF subtype Echocardiographic Parameters Paroxysmal AF (n=433) Persistent and Permanent AF (n=213) Significance (p value) LVEDD (cm) 4.8±3.0 5.0±0.9 0.29 LVESD (cm) 3.3±1.3 3.7±1.1 <0.01 IVS thickness (cm) 1.2±0.7 1.1±0.3 0.44 PW thickness (cm) 1.1±0.7 1.1±0.2 0.77 LV mass (g) 92.3±28.3 108.2±35.3 <0.01 LVEF (%) 56.1±14.1 47.4±16.8 <0.01 LA Expansion Index 89.4±69.1 53.4±40.3 <0.01 Min LA Volume indexed (ml/m2) 18.9±17.2 27.3±20.6 0.01 Max LA Volume indexed (ml/m2) 32.5±19.2 37.7±15.3 <0.01 LAEF (%) 41.8±16.4 31.5±13.6 <0.01

Conclusions

Our results suggest diabetes, IHD and PVD are associated with persistent/permanent AF. Additionally, greater LA remodeling and reduced atrial function was noted in this group, suggestive of an association between duration of AF electrical burden and LA remodeling and function.

P4353Global longitudinal strain is a measure of subclinical left ventricular dysfunction in chronic inflammatory autoimmune conditions

Background

Myocardial deformation indices are proposed to be a more sensitive marker of subclinical dysfunction compared to standard measures of left ventricular (LV) systolic function. We hypothesize that subclinical myocardial dysfunction is present in chronic inflammatory autoimmune diseases such as Systemic Lupus Erythematosus (SLE) and Rheumatoid Arthritis (RA), despite both conditions being mediated by different pro-inflammatory modulators.

Purpose

Identify subclinical myocardial dysfunction through assessment of global longitudinal strain in two different chronic autoimmune conditions, SLE and RA.

Methods

Consecutive patients admitted to our institution with known history of SLE or RA (>1 year disease activity) were examined. Patients with preexisting cardiac disease, LVEF <50% and those without comprehensive transthoracic echocardiograms (TTE) were excluded. Mean longitudinal LV strain was performed offline using vendor-independent software (TomTec v4.6) and compared to age- and gender-matched controls with normal LV function and no history of cardiac disease.

Results

Of the 86 patients examined (mean age 53.01±21.74, 85.4% female), 51 (59.3%) had SLE and 35 (40.7%) had RA. No significant difference in BMI, hypertension, hypercholesterolemia, diabetes, obesity, obstructive sleep apnea and stroke was observed between controls and patients with SLE or RA. While there was no significant difference in LVEF between RA patients and matched controls, there was a significantly lower GLS in the RA cohort. Conversely, patients with SLE had significantly lower LVEF and GLS when compared to matched controls, despite LVEF being in the normal range. See Table 1. Receiver operator curve analysis revealed that mean GLS is a better discriminator for autoimmune disease with an area under the curve of 0.829 (95% CI, 0.77 to 0.89; p<0.01) compared to LVEF with an area under the curve of 0.632 (95% CI, 0.55 to 0.72; p<0.01).

Echocardiographic Parameters SLE (n=51) Controls (n=51) Sig (p value) RA (n=35) Controls (n=35) Sig (p value) LVEDV (mls) 102±30 85±20 <0.01 84±28 89±30 0.43 LVESV (mls) 36±17 29±9 0.02 26±14 30±12 0.24 Biplane LVEF % 59±6 63±4 <0.01 62±6 62±5 0.81 LV Mass (grams/m2) 96±34 72±20 <0.01 79±26 82±23 0.67 LV Mean GLS % 16.7±2.8 21.3±2 <0.01 17.8±1.7 19.1±2.5 0.02

Conclusions

Our results suggest that chronic inflammatory conditions (SLE and RA) are associated with subclinical cardiac dysfunction. Impaired GLS may reflect early myocardial damage and be used as a tool for screening of patients with inflammatory conditions.

Acknowledgement/Funding

None

A Randomized Trial of Continuous Noninvasive Blood Pressure Monitoring During Noncardiac Surgery

BACKGROUND:

Intraoperative hypotension is associated with postoperative mortality. Early detection of hypotension by continuous hemodynamic monitoring might prompt timely therapy, thereby reducing intraoperative hypotension. We tested the hypothesis that continuous noninvasive blood pressure monitoring reduces intraoperative hypotension.

METHODS:

Patients ≥45 years old with American Society of Anesthesiologists physical status III or IV having moderate-to-high-risk noncardiac surgery with general anesthesia were included. All participating patients had continuous noninvasive hemodynamic monitoring using a finger cuff (ClearSight, Edwards Lifesciences, Irvine, CA) and a standard oscillometric cuff. In half the patients, randomly assigned, clinicians were blinded to the continuous values, whereas the others (unblinded) had access to continuous blood pressure readings. Continuous pressures in both groups were used for analysis. Time-weighted average for mean arterial pressure <65 mm Hg was compared using 2-sample Wilcoxon rank-sum tests and Hodges Lehmann estimation of location shift with corresponding asymptotic 95% CI.

RESULTS:

Among 320 randomized patients, 316 were included in the intention-to-treat analysis. With 158 patients in each group, those assigned to continuous blood pressure monitoring had significantly lower time-weighted average mean arterial pressure <65 mm Hg, 0.05 [0.00, 0.22] mm Hg, versus intermittent blood pressure monitoring, 0.11 [0.00, 0.54] mm Hg (P = .039, significance criteria P < .048).

CONCLUSIONS:

Continuous noninvasive hemodynamic monitoring nearly halved the amount of intraoperative hypotension. Hypotension reduction with continuous monitoring, while statistically significant, is currently of uncertain clinical importance.

Anesthetic considerations for bronchoscopic procedures: a narrative review based on the Cleveland Clinic experience

The advent of advanced diagnostic bronchoscopy has shown an increased demand for anesthesiologists to administer anesthesia in the bronchoscopy suite. Procedures such as navigational bronchoscopy, airway stenting and advanced therapeutic procedures often require the presence of an anesthesiologist to manage these more complex patients and procedures. In this review we describe the various bronchoscopic procedures and anesthetic management and complications of these procedures at our institution The Cleveland Clinic, Cleveland Ohio.

Faecal microbiota transplantation for eradicating carriage of multidrug-resistant organisms: a systematic review

BACKGROUND

Multidrug-resistant (MDR) microorganism development in the gut is frequently the result of inappropriate antibiotic use. Faecal microbiota transplantation (FMT) restores normal gut microbiota in patients with Clostridium difficile infection. We hypothesized that it may help in decolonizing MDR organisms (MDROs) and in preventing recurrent MDR infections.

OBJECTIVES

To assess FMT efficacy (eradication rate) for decolonizing MDROs and preventing recurrent MDR infections.

DATA SOURCES

Medline, Embase and Web of Science (inception through 11 February 2019).

STUDY ELIGIBILITY CRITERIA

Clinical trials, retrospective studies, case reports and case series.

PARTICIPANTS

Patients with MDR infections or MDRO colonization treated with FMT.

INTERVENTIONS

FMT.

METHODS

Systematic review.

RESULTS

Twenty-one studies (one randomized clinical trial, seven uncontrolled clinical trials, two retrospective cohort studies, two case series, nine case reports) assessing 192 patients were included. Three studies assessed FMT efficacy in preventing MDR infections; 16 assessed its effect on MDRO colonization; two assessed both. Data from 151 patients were included in the final analyses. In studies with low to moderate risk of bias, the eradication rate was 37.5% to 87.5%. Efficacy was similar in studies looking at infection or colonization and did not differ by length of follow-up. No serious adverse events from FMT were reported. Seven patients died of other causes.

CONCLUSIONS

FMT could be used as a treatment for eradicating MDR colonization and possibly preventing recurrent MDR infections, once more supporting efficacy and safety data are available. Larger well-designed randomized controlled trials are needed to further explore this therapy.

Regurgitation and pulmonary aspiration during cardio-pulmonary resuscitation (CPR) with a laryngeal tube: A pilot crossover human cadaver study

Background

High-quality chest compressions are imperative for Cardio-Pulmonary-Resuscitation (CPR). International CPR guidelines advocate, that chest compressions should not be interrupted for ventilation once a patient’s trachea is intubated or a supraglottic-airway-device positioned. Supraglottic-airway-devices offer limited protection against pulmonary aspiration. Simultaneous chest compressions and positive pressure ventilation both increase intrathoracic pressure and potentially enhances the risk of pulmonary aspiration. The hypothesis was, that regurgitation and pulmonary aspiration is more common during continuous versus interrupted chest compressions in human cadavers ventilated with a laryngeal tube airway.

Methods

Twenty suitable cadavers were included, and were positioned supine, the stomach was emptied, 500 ml of methylene-blue-solution instilled and laryngeal tube inserted. Cadavers were randomly assigned to: 1) continuous chest compressions; or, 2) interrupted chest compressions for ventilation breaths. After 14 minutes of the initial designated CPR strategy, pulmonary aspiration was assessed with a flexible bronchoscope. The methylene-blue-solution was replaced by 500 ml barium-sulfate radiopaque suspension. 14 minutes of CPR with the second designated ventilation strategy was performed. Pulmonary aspiration was then assessed with a conventional chest X-ray.

Results

Two cadavers were excluded for technical reasons, leaving 18 cadavers for statistical analysis. Pulmonary aspiration was observed in 9 (50%) cadavers with continuous chest compressions, and 7 (39%) with interrupted chest compressions (P = 0.75).

Conclusion

Our pilot study indicate, that incidence of pulmonary aspiration is generally high in patients undergoing CPR when a laryngeal tube is used for ventilation. Our study was not powered to identify potentially important differences in regurgitation or aspiration between ongoing vs. interrupted chest compression. Our results nonetheless suggest that interrupted chest compressions might better protect against pulmonary aspiration when a laryngeal tube is used for ventilation.

Suppressed heat shock protein response in the kidney of exercise-trained diabetic rats

Impaired expression of heat shock proteins (HSPs) and increased oxidative stress may contribute to the pathophysiology of diabetes by disrupted tissue protection. Acute exercise induces oxidative stress, whereas exercise training up-regulates endogenous antioxidant defenses and HSP expression. Although diabetic nephropathy is a major contributor to diabetic morbidity, information regarding the effect of HSPs on kidney protection is limited. This study evaluated the effects of eight-week exercise training on kidney HSP expression and markers of oxidative stress at rest and after acute exercise in rats with or without streptozotocin-induced diabetes. Induction of diabetes increased DNA-binding activity of heat shock factor-1, but decreased the expression of HSP72, HSP60, and HSP90. The inflammatory markers IL-6 and TNF-alpha were increased in the kidney tissue of diabetic animals. Both exercise training and acute exercise increased HSP72 and HSP90 protein levels only in non-diabetic rats. On the other hand, exercise training appeared to reverse the diabetes-induced histological changes together with decreased expression of TGF-beta as a key inducer of glomerulosclerosis, and decreased levels of IL-6 and TNF-alpha. Notably, HSP72 and TGF-beta were negatively correlated. In conclusion, impaired HSP defense seems to contribute to kidney injury vulnerability in diabetes and exercise training does not up-regulate kidney HSP expression despite the improvements in histopathological and inflammatory markers.