Atrial fibrosis by cardiac MRI is a correlate for atrial stiffness in patients with atrial fibrillation.

A relationship between left atrial strain and pressure has been demonstrated in many studies, but not in an atrial fibrillation (AF) cohort. In this work, we hypothesized that elevated left atrial (LA) tissue fibrosis might mediate and confound the LA strain vs. pressure relationship, resulting instead in a relationship between LA fibrosis and stiffness index (mean LA pressure/LA reservoir strain). Sixty-seven patients with AF underwent a standard cardiac MR exam including long-axis cine views (2 and 4-ch) and a free-breathing high resolution three-dimensional late gadolinium enhancement (LGE) of the atrium (N = 41), within 30 days prior to AF ablation, at which procedure invasive mean left atrial pressure (LAP) was measured. LV and LA Volumes, EF, and comprehensive analysis of LA strains (strain and strain rates and strain timings during the atrial reservoir, conduit and active, i.e. active atrial contraction, phases) were measured and LA fibrosis content (LGE (ml)) was assessed from 3D LGE volumes. LA LGE was well correlated to atrial stiffness index overall (R = 0.59, p < 0.001), and among patient subgroups. Pressure was only correlated to maximal LA volume (R = 0.32) and the time to peak reservoir strain rate (R = 0.32) (both p < 0.01), among all functional measurements. LA reservoir strain was strongly correlated with LAEF (R = 0.95, p < 0.001) and LA minimum volume (r = 0.82, p < 0.001). In our AF cohort, pressure is correlated to maximum LA volume and time to peak reservoir strain. LA pressure/ LA reservoir strain, a metric of stiffness, correlates with LA fibrosis (LA LGE), reflecting Hook's Law.

Marked QTc Reduction Immediately Following Direct Current Cardioversion of Atrial Fibrillation: Clinical Implications and Mechanisms.

BACKGROUND: The QTc in sinus rhythm (SR) following direct current cardioversion (DCCV) of atrial fibrillation (AF) is commonly used as a baseline QTc for patients who require initiation of antiarrhythmic drugs for rhythm control. Inaccurate baseline QTc may cause drug-induced torsades de pointes. OBJECTIVES: This study sought to assess time-dependent QTc changes following DCCV. METHODS: We prospectively assessed QTc changes with Bazett's QTc and Fridericia's QTc formulas in 65 patients following conversion of AF to SR. Among these 65 patients, 48 underwent DCCV and 17 spontaneously converted to SR. RESULTS: There was a large and statistically significant decrease in QTc in SR immediately following DCCV in 40 patients, which occurred with an abrupt reduction in heart rate postcardioversion. This finding excluded 8 patients with ventricular-paced QRS. The mean decrease from QTc in AF was 70.7 ± 37.2 milliseconds in the QTc interval for heart rate using Bazett's formula and 33.8 ± 17.9 milliseconds in the QTc interval for heart rate using Fridericia's formula at 1-minute post-DCCV. In 17 patients with spontaneous conversion from AF to SR, the QTc reduction was comparable to those in patients with DCCV. The QTc increased with time and reached a steady state at 5 minutes following conversion. Initiation of Class III drugs based on the "shortened" baseline QTc following DCCV was associated with drug-induced torsades de pointes. CONCLUSIONS: In patients with AF following conversion, regardless spontaneous or DCCV, the QTc shortened significantly with decreases in heart rate, likely via the mechanism of time-dependent rate adaption of ventricular repolarization. A steady-state QTc at 5-minutes following DCCV should be used as real baseline for guidance of pharmacotherapy in patients with AF.

Atrial Fibrosis by cardiac MRI is a correlate for atrial stiffness in patients with atrial fibrillation.

Aims: A relationship between left atrial strain and pressure has been demonstrated in many studies, but not in an atrial fibrillation (AF) cohort. In this work, we hypothesized that elevated left atrial (LA) tissue fibrosis might mediate and confound the LA strain vs. pressure relationship, resulting instead in a relationship between LA fibrosis and stiffness index (mean pressure/LA reservoir strain). Methods and Results: Sixty-seven patients with AF underwent a standard cardiac MR exam including long-axis cine views (2 and 4-ch) and a free-breathing high resolution three-dimensional late gadolinium enhancement (LGE) of the atrium (N=41), within 30 days prior to AF ablation, at which procedure invasive mean left atrial pressure (LAP) was measured. LV and LA Volumes, EF, and comprehensive analysis of LA strains (strain and strain rates and strain timings during the atrial reservoir, conduit and active phases) were measured and LA fibrosis content (LGE (ml)) was assessed from 3D LGE volumes. LA LGE was well correlated to atrial stiffness index (LA mean pressure/LA reservoir strain) overall (R=0.59, p<0.001), and among patient subgroups. Pressure was only correlated to maximal LA volume (R=0.32) and the time to peak reservoir strain rate (R=0.32), among all functional measurements. LA reservoir strain was strongly correlated with LAEF (R=0.95, p<0.001) and LA minimum volume (r=0.82, p<0.001). Conclusion: In our AF cohort, pressure is correlated to maximum LA volume and time to peak reservoir strain. LA LGE is a strong marker of stiffness.

Bilateral Pulmonary Embolism Masked by New-Onset Atrial Fibrillation with Rapid Ventricular Rate: The Role of Mechanical Thrombectomy.

BACKGROUND Management of atrial fibrillation (AF) with rapid ventricular rate in the setting of submassive pulmonary emboli (PE) has not been well defined in the literature. It is challenging as the hemodynamics caused by a PE can change the management of AF. We report a case of bilateral PE masked by new-onset AF with rapid ventricular rate that was treated pharmaceutically and mechanically, with thrombectomy. CASE REPORT An 85-year-old man presented with gradual dyspnea and was found to be in AF with rapid ventricular rate (~160-180 bpm). The patient had tachypnea and hypoxia requiring oxygen administration. On physical examination, he had euvolemia. Chest X-ray did not reveal pulmonary vascular congestion. He was started on standard AF management with atrioventricular nodal blockers. Laboratory tests revealed a normal troponin level but mildly elevated B-type natriuretic peptide and lactate. Because his dyspnea was out of proportion to the physical examination, radiographic, and laboratory findings, a D-dimer level was obtained and was elevated. Computed tomography with pulmonary angiogram showed extensive bilateral PE. An echocardiogram (TTE) showed evidence of right ventricular failure. The patient underwent mechanical thrombectomy with clot retrieval, deterring the risk of hemodynamic collapse that would have ensued with atrioventricular nodal blockers monotherapy. On repeat TTE, right ventricular dysfunction was completely resolved and the remaining hospitalization was uneventful. CONCLUSIONS In patients with concomitant AF with rapid ventricular rate and submassive PE, the use of mechanical thrombectomy, in addition to the standard AF management, could be beneficial in deterring the risk of hemodynamic collapse.

Severe extra-glandular involvement and pleural effusions complicating primary Sjogren's syndrome: a case report.

BACKGROUND: Sjogren's syndrome, an autoimmune disease of the exocrine glands, results in keratoconjunctivitis sicca, xerostomia, and dental caries. It is often overlooked, considered by clinicians to be a benign disease. However, it can cause life-threatening extra-glandular complications that affect multiple organ systems. CASE PRESENTATION: Here we present a 78-year-old Caucasian woman with a history of primary Sjogren's syndrome (pSS) whose symptoms of keratoconjunctivitis sicca were managed managed conservatively. She was evaluated for sub-acute shortness of breath. Imaging showed severe bronchiectasis with features of lymphocytic interstitial pneumonia. She also had exudative bilateral pleural effusions and skin ulcers, likely vasculitic in origin. The workup was significant for anti-Ro antibody, pancytopenia, hypocomplementia, cryoglobulinemia and monoclonal gammopathy, all of which reflect disease severity. Although there was no evidence of malignancy, she developed B-cell non-Hodgkin lymphoma during follow-up. CONCLUSIONS: Primary Sjogren's syndrome can result in severe multi-organ disease. Pleural effusions are a rare complication of pSS, with only ten cases reported in the literature over the last 30 years, and tend to respond well to steroids. Prognostic biomarkers for disease severity include hypocomplementia, cryoglobulinemia, monoclonal gammopathy, and hypergammaglobulinemia. In this report we review the literature and the management of the disease.

Angiographic Lesion Discordance in Women Presenting With Ischemic Heart Disease: Comparison of Visual Assessment, Quantitative Coronary Angiography, and Quantitative Flow Ratio.

BACKGROUND: Although visual assessment of stenosis severity is routinely used to guide coronary revascularization, there are concerns about its accuracy, especially in women, who present a higher variability in coronary anatomy and ischemic heart disease (IHD). The aim of this study was to assess whether quantitative coronary angiography (QCA) and quantitative flow ratio (QFR) could provide better discrimination of coronary stenosis severity and functional significance than visual assessment alone in women with IHD. METHODS: Coronary angiography was performed in a cohort of women with ischemic symptoms and non-invasive stress perfusion imaging. Visual assessment was done by blinded operators in clinical practice, while QCA and QFR were analyzed in an independent core laboratory. RESULTS: Ninety-nine consecutive patients with 101 lesions were included in the registry, and QFR was successfully measured in 81 lesions (80.2%). Visual assessment provided higher readings of angiographic severity than QCA in 50.5% (n = 51) of lesions. Mean absolute difference between QCA and visual assessment was significantly higher in lesions with >70% diameter stenosis (DS) (25.3 ± 7.3%), compared with both the 40%-55% (9.3 ± 6.8%; P<.001) and the <40% groups (7.0 ± 6.0%; P<.001). QFR was >0.80 in 33.3% of lesions with visually defined >70% DS, while all lesions with QCA-defined >70% DS had QFR ≤0.80. CONCLUSIONS: Interventional cardiologists' visual assessment results in a higher degree of coronary stenosis than QCA. Among women with ischemic symptoms and non-invasive stress perfusion imaging, additional lesion assessment by QCA and QFR may improve operators' ability to determine which patients and lesions will benefit from coronary revascularization.

Retrospective Comparison of Patients ≥ 80 Years With Atrial Fibrillation Prescribed Either an FDA-Approved Reduced or Full Dose Direct-Acting Oral Anticoagulant.

Direct-acting oral anticoagulants (DOACs) represent the standard for preventing stroke and systemic embolization (SSE) in patients with atrial fibrillation (AF). There is limited information for patients ≥ 80 years. We report a retrospective analysis of AF patients ≥ 80 years prescribed either a US Food and Drug Administration (FDA)-approved reduced (n = 514) or full dose (n = 199) DOAC (Dabigatran, Rivaroxaban, or Apixaban) between January 1st, 2011 (first DOAC commercially available) and May 31st, 2017. The following multivariable differences in baseline characteristics were identified: patients prescribed a reduced dose DOAC were older (p < 0.001), had worse renal function (p = 0.001), were more often prescribed aspirin (p = 0.004) or aspirin and clopidogrel (p < 0.001), and more often had new-onset AF (p = 0.001). SSE and central nervous system (CNS) bleed rates were low and not different (1.02 vs 0 %/yr and 1.45 vs 0.44 %/yr) for the reduced and full dose groups, respectively. For non-CNS bleeds, rates were 10.89 vs 4.15 %/yr (p < 0.001, univariable) for the reduced and full doses, respectively. The mortality rate was 6.24 vs 1.75 %/yr (p = 0.001, univariable) for the reduced and full doses. Unlike the non-CNS bleed rate, mortality rate differences remained significant when adjusted for baseline characteristics. Thus, DOACs in patients ≥ 80 with AF effectively reduce SSE with a low risk of CNS bleeding, independent of DOAC dose. The higher non-CNS bleed rate and not the mortality rate is explained by the higher risk baseline characteristics in the reduced DOAC dose group. Further investigation of the etiology of non-CNS bleeds and mortality is warranted.

Meta-Analysis of Gender Disparities in In-hospital Care and Outcomes in Patients with ST-Segment Elevation Myocardial Infarction.

Gender disparities in ST-segment elevation myocardial infarction (STEMI) outcomes continue to be reported worldwide; however, the magnitude of this gap remains unknown. To evaluate gender-based discrepancies in clinical outcomes and identify the primary driving factors a global meta-analysis was performed. Studies were selected if they included all comers with STEMI, reported gender specific patient characteristics, treatments, and outcomes, according to the registered PROSPERO protocol: CRD42020161469. A total of 56 studies (705,098 patients, 31% females) were included. Females were older, had more comorbidities and received less antiplatelet therapy and primary percutaneous coronary intervention (PCI). Females experienced significantly longer delays to first medical contact (mean difference 42.5 min) and door-to-balloon time (mean difference 4.9 min). In-hospital, females had increased rates of mortality (odds ratio [OR] 1.91, 95% confidence interval [CI] 1.84 to 1.99, p <0.00001), repeat myocardial infarction (MI) (OR 1.25, 95% CI 1.00 to 1.56, p=0.05), stroke (OR 1.67, 95% CI 1.27 to 2.20, p <0.001), and major bleeding (OR 1.82, 95% CI 1.56 to 2.12, p <0.00001) compared with males. Older age at presentation was the primary driver of excess mortality in females, although other factors including lower rates of primary PCI and aspirin usage, and longer door-to-balloon times contributed. In contrast, excess rates of repeat MI and stroke in females appeared to be driven, at least in part, by lower use of primary PCI and P2Y12 inhibitors, respectively. In conclusion, despite improvements in STEMI care, women continue to have in-hospital rates of mortality, repeat MI, stroke, and major bleeding up to 2-fold higher than men. Gender disparities in in-hospital outcomes can largely be explained by age differences at presentation but comorbidities, delays to care and suboptimal treatment experienced by women may contribute to the gender gap.

Fecal carriage of MDROs in a population of Lebanese elderly: Dynamics and impact on bacterial fitness.

Muti-Drug Resistant Organisms (MDROs) are problematic all over the world, especially in Lebanon. High fecal carriage rates of MDR Enterobacteriaceae were reported from Lebanese nursing homes. Some studies show that MDROs have a fitness cost as compared to sensitive isolates. In this study, the competitive growth of MDR Escherichia coli obtained from fecal samples from elderly is assessed. Fecal swabs from ten elderly patients from a Lebanese nursing home were obtained between June and December, 2015. Isolates were identified by API 20E and antimicrobial susceptibilities were determined. Production of ESBL (extended spectrum ß lactamase), MBL (metallo ß lactamse), AmpC and KPC (Klebsiella pneumonia carbapenemase) was detected phenotypically by the use of EDTA, PBA, cloxacillin, and DDSTs. In-vitro competition assays were performed using E. coli isolates with different combinations of bacterial resistance. A total of 117 isolates was obtained with 71.8% E. coli, 7.7% of which were ESBL and 5.1% AmpC producers. Sensitive E. coli isolates out-competed all other isolates when in competition, followed sequentially by ESBL, AmpC, and OXA-48 (oxacillin) producers. This study shows an advantage of sensitive E. coli strains obtained from fecal samples to out-compete resistant strains in specific in-vitro conditions. This ability could be exploited in the elimination of MDR organisms from the gut flora, after further investigation.