Browsing by Author "Barnett, Adam S"

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    Catheter ablation of atrial fibrillation in patients with diabetes mellitus.
    (Heart rhythm O2, 2020-08) Wang, Allen; Truong, Tracy; Black-Maier, Eric; Green, Cynthia; Campbell, Kristen B; Barnett, Adam S; Febre, Janice; Loring, Zak; Al-Khatib, Sana M; Atwater, Brett D; Daubert, James P; Frazier-Mills, Camille; Hegland, Donald D; Jackson, Kevin P; Jackson, Larry R; Koontz, Jason I; Lewis, Robert K; Pokorney, Sean D; Sun, Albert Y; Thomas, Kevin L; Bahnson, Tristam D; Piccini, Jonathan P

    Background

    Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). Few studies have compared clinical outcomes after catheter ablation between patients with and those without DM.

    Objective

    The purpose of this study was to compare AF ablation outcomes in patients with and those without DM.

    Methods

    We performed a retrospective analysis of 351 consecutive patients who underwent first-time AF ablation. Clinical outcomes included freedom from recurrent atrial arrhythmia, symptom burden (Mayo AF Symptom Inventory score), cardiovascular and all-cause hospitalizations, and periprocedural complications.

    Results

    Patients with DM (n = 65) were older, had a higher body mass index, more persistent AF, more hypertension, and larger left atrial diameter (P <.05 for all). Median (Q1, Q3) total radiofrequency duration [64.0 (43.6, 81.4) minutes vs 54.3 (39.2, 76.4) minutes; P = .132] and periprocedural complications (P = .868) did not differ between patients with and those without DM. After a median follow-up of 29.5 months, arrhythmia recurrence was significantly higher in the DM group compared to the no-DM group after adjustment for baseline differences (adjusted hazard ratio [HR] 2.24; 95% confidence [CI] 1.42-3.55; P = .001). There was a nonsignificant trend toward higher AF recurrence with worse glycemic levels (HR 1.29; 95% CI 0.99-1.69; P = .064).

    Conclusion

    Although safety outcomes associated with AF ablation were similar between patients with and those without DM, arrhythmia-free survival was significantly lower among patients with DM. Poor glycemic control seems to an important risk factor for AF recurrence.
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    Crizotinib Inhibits Hyperpolarization-activated Cyclic Nucleotide-Gated Channel 4 Activity.
    (Cardio-oncology (London, England), 2017-01) Zhang, Zhushan; Huang, Tai-Qin; Nepliouev, Igor; Zhang, Hengtao; Barnett, Adam S; Rosenberg, Paul B; Ou, Sai-Hong I; Stiber, Jonathan A
    Sinus bradycardia is frequently observed in patients treated with crizotinib, a receptor tyrosine kinase inhibitor used for the treatment of anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). We investigated whether crizotinib could influence heart rate (HR) through direct cardiac effects. The direct effect of crizotinib on HR was studied using ECG analysis of Langendorff-perfused mouse hearts. The whole-cell patch clamp technique was used to measure the effects of crizotinib on the hyperpolarization-activated funny current, If, in mouse sinoatrial node cells (SANCs) and hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) activity in HEK-293 cells stably expressing human HCN4. Crizotinib resulted in a dose-dependent reduction in HR in isolated intact mouse hearts with a half maximal inhibitory concentration (IC50) of 1.7 ± 0.4 μmol/L. Because ECG analysis revealed that crizotinib (0-5 μmol/L) resulted in significant reductions in HR in isolated mouse hearts without changes in PR, QRS, or QT intervals, we performed whole-cell patch clamp recordings of SANCs which showed that crizotinib inhibited If which regulates cardiac pacemaker activity. Crizotinib resulted in diminished current density of HCN4, the major molecular determinant of If, with an IC50 of 1.4 ± 0.3 μmol/L. Crizotinib also slowed HCN4 activation and shifted the activation curve to the left towards more hyperpolarized potentials. Our results suggest that crizotinib's effects on HCN4 channels play a significant role in mediating its observed effects on HR.
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    Diagnosis of Capnocytophaga canimorsus Sepsis by Whole-Genome Next-Generation Sequencing.
    (Open Forum Infect Dis, 2016-09) Abril, Maria K; Barnett, Adam S; Wegermann, Kara; Fountain, Eric; Strand, Andrew; Heyman, Benjamin M; Blough, Britton A; Swaminathan, Aparna C; Sharma-Kuinkel, Batu; Ruffin, Felicia; Alexander, Barbara D; McCall, Chad M; Costa, Sylvia F; Arcasoy, Murat O; Hong, David K; Blauwkamp, Timothy A; Kertesz, Michael; Fowler, Vance G; Kraft, Bryan D
    We report the case of a 60-year-old man with septic shock due to Capnocytophaga canimorsus that was diagnosed in 24 hours by a novel whole-genome next-generation sequencing assay. This technology shows great promise in identifying fastidious pathogens, and, if validated, it has profound implications for infectious disease diagnosis.
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    Noninvasive electrocardiographic mapping of ventricular tachycardia in a patient with a left ventricular assist device.
    (HeartRhythm case reports, 2020-07) Rehorn, Michael R; Koontz, Jason; Barnett, Adam S; Black-Maier, Eric; Piccini, Jonathan P; Loring, Zak; Schroder, Jacob; Sun, Albert Y
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    Predicting atrial fibrillation recurrence after ablation in patients with heart failure: Validity of the APPLE and CAAP-AF risk scoring systems.
    (Pacing and clinical electrophysiology : PACE, 2019-11) Black-Maier, Eric; Parish, Alice; Steinberg, Benjamin A; Green, Cynthia L; Loring, Zak; Barnett, Adam S; Al-Khatib, Sana M; Atwater, Brett D; Daubert, James P; Frazier-Mills, Camille; Hegland, Donald D; Jackson, Kevin P; Jackson, Larry R; Koontz, Jason; Lewis, Robert K; Pokorney, Sean D; Sun, Albert Y; Thomas, Kevin L; Bahnson, Tristam D; Piccini, Jonathan P

    Background

    Compared with medical therapy, catheter ablation of atrial fibrillation (AF) in patients with heart failure (HF) improves cardiovascular outcomes. Risk scores (CAAP-AF and APPLE) have been developed to predict the likelihood of AF recurrence after ablation, have not been validated specifically in patients with AF and HF.

    Methods

    We analyzed baseline characteristics, risk scores, and rates of AF recurrence 12 months postablation in a cohort of 230 consecutive patients with AF and HF undergoing PVI in the Duke Center for Atrial Fibrillation registry from 2009-2013.

    Results

    During a follow-up period of 12 months, 76 of 230 (33%) patients with HF experienced recurrent AF after ablation. The median APPLE and CAAP-AF scores were 1.5 ([Q1, Q3]: [1.0, 2.0]) and 4.0 ([Q1, Q3]: [3.0, 5.0]), respectively and were not different from those patients with and without recurrent AF. Freedom from AF was not different according to APPLE and CAAP-AF scores. Discrimination for recurrent AF with the CAAP-AF score was modest with a C-statistic of 0.60 (95% CI 0.52-0.67). Discrimination with the APPLE score was similarly modest, with a C-statistic of 0.54 (95% CI: 0.47-0.62).

    Conclusions

    Validated predictive risk scores for recurrent AF after catheter ablation exhibit limited predictive ability in cohorts of AF and HF. Additional tools are needed to facilitate risk stratification and patient selection for AF ablation in patients with concomitant HF.