Back to Authors

El‐Chami, Mikhael F.

https://orcid.org/0000-0003-4978-7177

Mayo Clinic

Emory University Hospital

Citations 11

Left Atrial Appendage Occlusion vs Standard of Care After Ischemic Stroke Despite Anticoagulation
Seiffge, David , Group, STR-OAC LAAO, Macha, Kosmas , Takagi, Masahito, Arihiro, Shoji , Polymeris, Alexandros A. , Yoshimura, Sohei , Venti, Michele , Thilemann, Sebastian , Altavilla, Riccardo , Peters, Nils , Inoue, Manabu, Bobinger, Tobias , Agnelli, Giancarlo , Acciarresi, Monica, Jager, Hans, Bovi, Paolo, Schwab, Stefan , Registry, RAF, RAF-DOAC, CROMIS-2, SAMURAI, NOACISP, Erlangen Registry, and Verona, Aarnink, Errol W. , Fierro, Nicolai, Tondo, Claudio , Zieliński, Kamil , Korsholm, Kasper , Nielsen-Kudsk, Jens Erik, Caneiro‐Queija, Berenice, Benito‐González, Tomás , Holmes, David R. , Almakadma, Abdul H., Álvarez, Xavier Millán, Alla, Venkata , Agarwal, Himanshu , Paitazoglou, Christina , Freixa, Xavier , Cepas‐Guillén, Pedro , Chothia, Rashaad , Badejoko, Solomon O. , Bergmann, Martin , Spoon, Daniel B., Maddux, James T., Ram, Pradhum , Branca, Luca , Dijk, Vincent F. van , Rensing, Benno J. , Paciaroni, Maurizio , Kallmünzer, Bernd , Wilson, Duncan , Jäger, Hans Rolf , Korsholm, Kasper , Seiffge, David , Jäger, Hans Rolf , Cepas-Guillen, Pedro , Maarse, Moniek , Werring, David J. , Boersma, Lucas V.A. , Group, STR-OAC LAAO, Tsivgoulis, Georgios , Bonetti, Bruno , Alberti, Andrea , Ambler, Gareth , Bonati, Leo H. , Muir, Keith W. , Yamagami, Hiroshi, Inoue, Manabu , Brown, Martin M. , Sato, Shoichiro , Lyrer, Philippe A. , Marchis, Gian Marco De , Peper, Joyce , Simard, Trevor , Alkhouli, Mohamad , Registry, RAF, RAF-DOAC, CROMIS-2, SAMURAI, NOACISP, Erlangen Registry, and Verona, Mazzone, Patrizio , Beneduce, Alessandro , Gasperetti, Alessio , Pracoń, Radosław , Demkow, Marcin , Backer, Ole De , Nielsen‐Kudsk, Jens Erik , Estévez‐Loureiro, Rodrigo , Prado, Armando Pérez de , Nombela‐Franco, Luis , Salinas, Pablo , Berti, Sérgio , Romeo, Maria Rita , Arzamendi, Dabit , Eitel, Ingo , Bergmann, Martin W., El‐Chami, Mikhael F. , Adamo, Marianna , Suradi, Hussam , Zietz, Annaelle , Caso, Valeria , Koga, Masatoshi , Toyoda, Ḱazunori , Cappellari, Manuel , Engelter, Stefan T. , Swaans, Martin John

JAMA Neurology | September 23, 2024 | Volume: 81 | Issue: 11 | Pages: 1150

10.1001/jamaneurol.2024.2882 Get It

ImportancePatients with atrial fibrillation (AF) who have ischemic stroke despite taking oral anticoagulation therapy (OAT) have a very high risk of recurrence. Left atrial appendage occlusion (LAAO) is a mechanical stroke prevention strategy that may provide additional protection in patients with thromboembolic events under OAT.ObjectiveTo compare percutaneous LAAO with continuing OAT alone regarding stroke prevention in patients with AF who had a thromboembolic event despite taking OAT.Design, Setting, and ParticipantsThis cohort study was a propensity score–matched comparison of the STR-OAC LAAO cohort, an international collaboration of 21 sites combining patients from multiple prospective registries of patients who underwent LAAO between 2010 and 2022. STR-OAC LAAO cohort patients who had follow-up longer than 3 months were propensity score–matched to a previously published control cohort comprising patients from an established international collaboration of investigator-initiated prospective studies. This control cohort included patients with nonvalvular AF, recent ischemic stroke or transient ischemic attack, and follow-up longer than 3 months who were taking OAT before the index event. Analyses were adjusted for imbalances in gender, age, hypertension, diabetes, and CHA2 DS2-VASc score.ExposureLeft atrial appendage occlusion vs continuation of oral anticoagulation therapy alone (control group).Main Outcomes and MeasuresThe primary outcome was time to first ischemic stroke.ResultsFour hundred thirty-three patients from the STR-OAC LAAO cohort (mean [SD] age, 72 [9] years; 171 [39%] females and 262 [61%] males; mean [SD] CHA2 DS2-VASc score, 5.0 [1.6]) were matched to 433 of 1140 patients (38%) from the control group. During 2-year follow-up, 50 patients experienced ischemic stroke: an annualized event rate of 2.8% per patient-year in the STR-OAC LAAO group vs 8.9% per patient-year in the control group. Left atrial appendage occlusion was associated with a lower risk of ischemic stroke (hazard ratio, 0.33; 95% CI, 0.19-0.58; P < .001) compared with the control group. After LAAO, OAT was discontinued in 290 patients (67%), and the remaining 143 patients (33%) continued OAT after LAAO as an adjunctive therapy.Conclusions and RelevanceIn patients with nonvalvular AF and a prior thromboembolic event despite taking OAT, LAAO was associated with a lower risk of ischemic stroke compared with continued OAT alone. Randomized clinical trial data are needed to confirm that LAAO may be a promising treatment option for this population with a very high risk of stroke.
Leadless pacemakers at 5-year follow-up: the Micra transcatheter pacing system post-approval registry
Garweg, Christophe , Clementy, Nicolas, Al-Samadi, Faisal, Iacopino, Saverio , Roberts, Paul R. , Johansen, Jens Brock , Vinolas-Prat, X., Cha, Yong‐Mei , Grubman, Eric , Bordachar, Pierre , Fagan, Dedra H. , Piccini, Jonathan P. , El-Chami, Mikhael F , Garweg, Christophe , Johansen, Jens Brock , Cha, Yong-Mei , Stromberg, Kurt , El‐Chami, Mikhael F. , Clémenty, Nicolas , Martínez‐Sande, José Luis , Tondo, Claudio , Stromberg, Kurt

European Heart Journal | February 9, 2024 | Volume: 45 | Issue: 14 | Pages: 1241-1251

10.1093/eurheartj/ehae101 Get It

Abstract Background and Aims Prior reports have demonstrated a favourable safety and efficacy profile of the Micra leadless pacemaker over mid-term follow-up; however, long-term outcomes in real-world clinical practice remain unknown. Updated performance of the Micra VR leadless pacemaker through five years from the worldwide post-approval registry (PAR) was assessed. Methods All Micra PAR patients undergoing implant attempts were included. Endpoints included system- or procedure-related major complications and system revision rate for any cause through 60 months post-implant. Rates were compared through 36 months post-implant to a reference dataset of 2667 transvenous pacemaker patients using Fine–Gray competing risk models. Results 1809 patients were enrolled between July 2015 and March 2018 and underwent implant attempts from 179 centres in 23 countries with a median follow-up period of 51.1 months (IQR: 21.6–64.2). The major complication rate at 60 months was 4.5% [95% confidence interval (CI): 3.6%–5.5%] and was 4.1% at 36 months, which was significantly lower than the 8.5% rate observed for transvenous systems (HR: .47, 95% CI: .36–.61; P < .001). The all-cause system revision rate at 60 months was 4.9% (95% CI: 3.9%–6.1%). System revisions among Micra patients were mostly for device upgrades (41.2%) or elevated thresholds (30.6%). There were no Micra removals due to infection noted over the duration of follow-up. At 36 months, the system revision rate was significantly lower with Micra vs. transvenous systems (3.2% vs. 6.6%, P < .001). Conclusions Long-term outcomes with the Micra leadless pacemaker continue to demonstrate low rates of major complications and system revisions and an extremely low incidence of infection.
Process mapping strategies to prevent subcutaneous implantable cardioverter‐defibrillator infections
Weiss, Raul , Mark, George E., Lambiase, Pier D. , Miller, Marc A. , McClernon, Timothy R., Knight, Bradley P. , El-Chami, Mikhael F , Miller, Marc A , Lambiase, Pier D , Knight, Bradley P , Weiss, Raul , El‐Chami, Mikhael F. , Biffi, Mauro , Probst, Vincent , Hansen, Linda K. , Baddour, Larry M.

Journal of Cardiovascular Electrophysiology | June 4, 2022 | Volume: 33 | Issue: 7 | Pages: 1628-1635

10.1111/jce.15566 Get It

AbstractBackgroundInfection remains a major complication of cardiac implantable electronic devices and can lead to significant morbidity and mortality. Implantable devices that avoid transvenous leads, such as the subcutaneous implantable cardioverter‐defibrillator (S‐ICD), can reduce the risk of serious infection‐related complications, such as bloodstream infection and infective endocarditis. While the 2017 AHA/ACC/HRS guidelines include recommendations for S‐ICD use for patients at high risk of infection, currently, there are no clinical trial data that address best practices for the prevention of S‐ICD infections. Therefore, an expert panel was convened to develop a consensus on these topics.MethodsAn expert process mapping methodology was used to achieve consensus on the appropriate steps to minimize or prevent S‐ICD infections. Two face‐to‐face meetings of high‐volume S‐ICD implanters and an infectious diseases specialist, with expertise in cardiovascular implantable electronic device infections, were conducted to develop consensus on useful strategies pre‐, peri‐, and postimplant to reduce S‐ICD infection risk.ResultsExpert panel consensus on recommended steps for patient preparation, S‐ICD implantation, and postoperative management was developed to provide guidance in individual patient management.ConclusionAchieving expert panel consensus by process mapping methodology for S‐ICD infection prevention was attainable, and the results should be helpful to clinicians in adopting interventions to minimize risks of S‐ICD infection.
Abstract 12087: Device-Related Infection Associated With Increased Mortality Risk in de novo Transvenous Implantable Cardioverter-Defibrillator Medicare Patients
Liu, Yiyan , Weiss, Raul, Mark, George E., Lambiase, Pier D. , Miller, Marc A. , Jacobsen, Caroline, Lambiase, Pier D , El‐Chami, Mikhael F. , Griffiths, Robert, Knight, Bradley P. , Biffi, Mauro , Probst, Vincent , Jacobsen, Caroline M., Baddour, Larry M.

Circulation | April 28, 2022 | Volume: 144 | Issue: Suppl_1 | Pages: No page available

10.1161/circ.144.suppl_1.12087 Get It

Introduction: Device-related infection is estimated to occur in 1.9% of the Medicare patients with de novo transvenous (TV) implantable cardioverter-defibrillators (ICD) within 2 years post-implant. TV-ICD infection is a serious complication that frequently requires complete device removal for attempted cure, which can be associated with patient morbidity and mortality. The objective of this study is to expand on limited published data and assess mortality risk associated with TV-ICD infection in a large Medicare population with de novo TV-ICD implants. Methods: A survival analysis was conducted using 100% fee-for-service Medicare facility-level claims data to identify patients who underwent de novo TV-ICD implantation between 7/2016 and 1/2018. TV-ICD infection within 2 years of implantation was identified using ICD-10 and CPT codes. Baseline patient risk factors associated with mortality were identified using the Charlson Comorbidity Index categories. Infection was treated as a time-dependent variable in a multivariate Cox proportional hazards model to account for immortal time bias. Results: Among 26,742 Medicare patients with de novo TV-ICD, 518 (1.9%) had a device-related infection. The overall number of decedents was 4,721 (17.7%) over 2 years, with 4,555 (17%) in the non-infection group and 166 (32%) in the infection group. After adjusting for baseline patient demographic characteristics and various comorbidities, the presence of TV-ICD infection was associated with an increase of 2.4 [95% CI: 2.08-2.85] times in the mortality hazard ratio (see attached Figure). Most of the baseline patient risk factors were also associated with higher risk of mortality in the Cox model. Conclusion: The rate of de novo TV-ICD infection and associated mortality in a large, real-world Medicare population is noteworthy. The positive association between device-related infection and risk of mortality further highlights the need to reduce infections.
Device‐related infection associated with increased mortality risk in de novo transvenous implantable cardioverter‐defibrillator medicare patients
Liu, Yiyan , Griffiths, Robert I. , Knight, Bradley P. , Weiss, Raul , Mark, George E., Lambiase, Pier D. , Miller, Marc A. , Jacobsen, Caroline M., El-Chami, Mikhael F , Weiss, Raul , Miller, Marc A , Lambiase, Pier D , Knight, Bradley P , El‐Chami, Mikhael F. , Biffi, Mauro , Probst, Vincent , Baddour, Larry M.

Journal of Cardiovascular Electrophysiology | January 23, 2022 | Volume: 33 | Issue: 4 | Pages: 725-730

10.1111/jce.15385 Get It

AbstractIntroductionTransvenous implantable cardioverter‐defibrillators (TV‐ICD) infection is a serious complication that frequently requires complete device removal for attempted cure, which can be associated with patient morbidity and mortality. The objective of this study is to assess mortality risk associated with TV‐ICD infection in a large Medicare population with de novo TV‐ICD implants.MethodsA survival analysis was conducted using 100% fee‐for‐service Medicare facility‐level claims data to identify patients who underwent de novo TV‐ICD implantation between 7/2016 and 1/2018. TV‐ICD infection within 2 years of implantation was identified using International Classification of Disease, 10th Edition and current procedural terminology codes. Baseline patient risk factors associated with mortality were identified using the Charlson Comorbidity Index categories. Infection was treated as a time‐dependent variable in a multivariate Cox proportional hazards model to account for immortal time bias.ResultsAmong 26,742 Medicare patients with de novo TV‐ICD, 518 (1.9%) had a device‐related infection. The overall number of decedents was 4721 (17.7%) over 2 years, with 4555 (17%) in the noninfection group and 166 (32%) in the infection group. After adjusting for baseline patient demographic characteristics and various comorbidities, the presence of TV‐ICD infection was associated with an increase of 2.4 (95% CI: 2.08–2.85) times in the mortality hazard ratio.ConclusionThe rate of TV‐ICD infection and associated mortality in a large, real‐world Medicare population is noteworthy. The positive association between device‐related infection and risk of mortality further highlights the need to reduce infections
Process Mapping Strategies to Prevent Subcutaneous Implantable Cardioverter-Defibrillator Infection
Weiss, Raul , Mark, G. J., Miller, Marc A. , McClernon, Timothy R., Weiss, Raul , Mark, George, El‐Chami, Mikhael F. , Biffi, Mauro , Probst, Vincent , Lambiase, Pier D. , Hansen, Linda, Knight, Bradley P. , Baddour, Larry M.

No container title available | January 2, 2022 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.22541/au.164118494.47265902/v1 Get It

Background: Infection remains a major complication of cardiac implantable electronic devices (CIEDs) and can lead to significant morbidity and mortality. Extrathoracic devices that avoid epicardial or transvenous leads, such as the subcutaneous implantable cardioverter-defibrillator (S-ICD), can reduce the risk of serious infection-related complications, such as bloodstream infection and infective endocarditis. While the 2017 AHA/ACC/HRS guidelines include recommendations for S-ICD use for patients at high risk of infection, currently, there are no clinical trial data that address best practices for the prevention of S-ICD infections. Therefore, an expert panel was convened to develop consensus on these topics. Methods: An expert process mapping methodology was used to achieve consensus on the appropriate steps to minimize or prevent S-ICD infections. Two face-to-face meetings of high-volume S-ICD implanters and an infectious diseases specialist, with expertise on cardiovascular implantable electronic device infections, were conducted to develop consensus on useful strategies pre-, peri-, and post-implant to reduce S-ICD infection risk. Results: Expert panel consensus of recommended steps for patient preparation, S-ICD implantation, and post-operative management were developed to provide guidance in individual patient management. Conclusion: Achieving expert panel consensus by process mapping methodology for S-ICD infection prevention was attainable, and the results should be helpful to clinicians in adopting interventions to minimize risks of S-ICD infection.
Abstract 15562: Incidence and Risk Factors of Device-related Infection in De Novo Transvenous Implantable Cardiac Defibrillator Medicare Patients
Jacobsen, Caroline M., Wold, Nicholas , Amorosi, Stacey L., Stivland, Timothy M. , Mark, George E., Lambiase, Pier D. , Miller, Marc A. , Lambiase, Pier D , El‐Chami, Mikhael F. , Griffiths, Robert I, Hansen, Linda K. , Knight, Bradley P. , Weiss, Raul , Biffi, Mauro , Probst, Vincent , Baddour, Larry M.

Circulation | May 10, 2021 | Volume: 142 | Issue: Suppl_3 | Pages: No page available

10.1161/circ.142.suppl_3.15562 Get It

Introduction: Practice guidelines recommend use of subcutaneous implantable cardioverter-defibrillators (ICD) in patients (pts) at risk of sudden cardiac death and high risk for infection. This has prompted a need to better identify pts at high risk of infection to assist in de novo device selection. The objective of this study is to estimate infection incidence in de novo transvenous (TV) ICD implants and assess risk factors associated with infection in a large Medicare population. Methods: A retrospective cohort study was conducted using 100% Medicare administrative and claims data to identify pts who underwent de novo TV-ICD implantation between 7/2016 and 1/2018. Device-related infection within 2 years of implantation was identified using ICD-10 diagnosis and procedure codes. Baseline pt factors associated with infection were identified by univariable logistic regression analysis of all variables of interest, including factors in Charlson and Elixhauser comorbidity indices, followed by stepwise selection criteria with a p≤0.25 for inclusion in a multivariable model and a backwards, stepwise elimination process with p≤0.1 to remain in the model. A time-to-event analysis was also conducted. Results: Among 26,742 pts with de novo TV-ICD, 519 (1.9%) had a device-related infection over 2 years. The mean pt age with and without infection was 68 and 71 years, respectively. While more than half (54%) of infections occurred within 90 days post implant, infections continued to be diagnosed with 16% of infections occurring between years 1 and 2. Multivariable analysis revealed several significant predictors of infection (Figure) including age <70 years, end stage renal disease with chronic dialysis and diabetes with complications. Conclusion: The rate of de novo TV-ICD infection in a large real-world Medicare population is clinically significant. The factors associated with increased infection risk identified here can be used to help determine device selection.
Response to the letter to the editor: Wettability and roughness: Important determinants of bacterial adhesion and biofilm formation
Mayotte, Jane , Bonner, Matt, Holbrook, Reece , Stromberg, Kurt , Sohail, M. Rizwan , El-Chami, Mikhael F , Sohail, M Rizwan , Stromberg, Kurt , El‐Chami, Mikhael F.

Journal of Cardiovascular Electrophysiology | May 2, 2020 | Volume: 31 | Issue: 7 | Pages: 1886-1887

10.1111/jce.14517 Get It

Diagnosis and management of subcutaneous implantable cardioverter‐defibrillator infections based on process mapping
Baddour, Larry M. , Weiss, Raul , Mark, George E., Biffi, Mauro , Probst, Vincent , Lambiase, Pier D. , Miller, Marc A. , McClernon, Timothy R., Hansen, Linda K. , Knight, Bradley P. , El-Chami, Mikhael F , Biffi, Mauro , Probst, Vincent , Lambiase, Pier D , Hansen, Linda K , Knight, Bradley P , Baddour, Larry , Weiss, Raul , El‐Chami, Mikhael F.

Pacing and Clinical Electrophysiology | April 8, 2020 | Volume: 43 | Issue: 9 | Pages: 958-965

10.1111/pace.13902 Get It

AbstractBackgroundInfection is a well‐recognized complication of cardiovascular implantable electronic device (CIED) implantation, including the more recently available subcutaneous implantable cardioverter‐defibrillator (S‐ICD). Although the AHA/ACC/HRS guidelines include recommendations for S‐ICD use, currently there are no clinical trial data that address the diagnosis and management of S‐ICD infections. Therefore, an expert panel was convened to develop consensus on these topics.MethodsA process mapping methodology was used to achieve a primary goal – the development of consensus on the diagnosis and management of S‐ICD infections. Two face‐to‐face meetings of panel experts were conducted to recommend useful information to clinicians in individual patient management of S‐ICD infections.ResultsPanel consensus of a stepwise approach in the diagnosis and management was developed to provide guidance in individual patient management.ConclusionAchieving expert panel consensus by process mapping methodology in S‐ICD infection diagnosis and management was attainable, and the results should be helpful in individual patient management.
Reduced bacterial adhesion with parylene coating: Potential implications for Micra transcatheter pacemakers
Mayotte, Jane , Bonner, Matt, Holbrook, Reece , Stromberg, Kurt , Sohail, M. Rizwan , El-Chami, Mikhael F , Sohail, M Rizwan , Stromberg, Kurt , El‐Chami, Mikhael F.

Journal of Cardiovascular Electrophysiology | February 3, 2020 | Volume: 31 | Issue: 3 | Pages: 712-717

10.1111/jce.14362 Get It

Abstract Introduction Infections of cardiac implantable electronic devices remain a prevalent health concern necessitating the advent of novel preventative strategies. Based on the observation that bacterial infections of the Micra transcatheter pacemaker device are extremely rare, we examine the effect of parylene coating on bacterial adhesion and growth. Methods Bacterial growth was compared on polyurethane coated, bare, or parylene coated titanium surfaces. Eight test samples per bacterial species and material combination were incubated with Staphylococcus Aureus or Pseudomonas aeruginosa for 24 hours and then assayed for bacterial growth. The surface contact angle was also characterized by measuring the angle between the tangent to the surface of a liquid droplet made with the surface of the solid sample. Results The mean bacterial colony counts were significantly reduced for both parylene coated titanium versus bare samples (3.69 ± 0.27 and 4.80 ± 0.48 log[CFU/mL] respectively for S. aureus [ P < .001] and 5.51 ± 0.27 and 6.08 ± 0.11 log[CFU/mL] respectively for P. aeruginosa [ P < .001]), and for parylene coated titanium versus polyurethane samples (4.27 ± 0.42 and 5.40 ± 0.49 log[CFU/mL] respectively for S. aureus [ P < .001] and 4.23 ± 0.42 and 4.84 ± 0.32 log[CFU/mL] respectively for P. aeruginosa [ P = .006]). Parylene coated titanium samples had a higher contact angle compared with bare titanium, but lower compared with polyurethane (mean contact angle 87.5 ± 3.1 degrees parylene, 73.3 ± 3.7 degrees titanium [ P < .001 vs parylene], and 94.8 ± 3.7 degrees polyurethane [ P = .002 vs parylene]). Conclusions Parylene coating significantly reduced the ability of bacteria to grow in colony count assays suggesting that this could contribute to the reduction of bacterial infections of Micra transcatheter pacemakers.