2022
Sex-based differences in atrial fibrillation ablation adverse events
Mszar R, Friedman D, Ong E, Du C, Wang Y, Zeitler E, Cunningham S, Akar J, Curtis J, Freeman J. Sex-based differences in atrial fibrillation ablation adverse events. Heart 2022, 109: 595-605. PMID: 36104219, DOI: 10.1136/heartjnl-2022-321192.Peer-Reviewed Original ResearchMeSH KeywordsAdultAtrial FibrillationCatheter AblationCohort StudiesFemaleHumansLungMaleQuality of LifeTreatment OutcomeConceptsAcute pulmonary vein isolationAdverse eventsPulmonary vein isolationAtrial fibrillationHigh riskSex-based differencesVein isolationCatheter ablationFemale sexLarge prospective registryHospital adverse eventsMajor adverse eventsObservational cohort studyPhrenic nerve damageAF ablation proceduresQuality of lifeAblation RegistryMore comorbiditiesProspective registryAF ablationCohort studyPericardial effusionNerve damagePatient sexVascular injury
2021
Lack of Guideline-Directed Medical Therapy in Patients Undergoing Endovascular Procedures for Critical Limb Ischemia
Llanos-Chea F, Jelani QU, Trejo-Paredes C, Curtis JP, Parzynski CS, Huang J, Faridi KF, Turner J, Smolderen KG, Mena-Hurtado C. Lack of Guideline-Directed Medical Therapy in Patients Undergoing Endovascular Procedures for Critical Limb Ischemia. Journal Of The American College Of Cardiology 2021, 77: 1374-1375. PMID: 33706882, DOI: 10.1016/j.jacc.2020.12.063.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overAngiotensin Receptor AntagonistsAngiotensin-Converting Enzyme InhibitorsCohort StudiesEndovascular ProceduresFemaleGuideline AdherenceHumansHydroxymethylglutaryl-CoA Reductase InhibitorsIschemiaMaleMiddle AgedPeripheral Arterial DiseasePlatelet Aggregation Inhibitors
2020
Revascularization Practices and Outcomes in Patients With Multivessel Coronary Artery Disease Who Presented With Acute Myocardial Infarction and Cardiogenic Shock in the US, 2009-2018
Khera R, Secemsky EA, Wang Y, Desai NR, Krumholz HM, Maddox TM, Shunk KA, Virani SS, Bhatt DL, Curtis J, Yeh RW. Revascularization Practices and Outcomes in Patients With Multivessel Coronary Artery Disease Who Presented With Acute Myocardial Infarction and Cardiogenic Shock in the US, 2009-2018. JAMA Internal Medicine 2020, 180: 1317-1327. PMID: 32833024, PMCID: PMC9377424, DOI: 10.1001/jamainternmed.2020.3276.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedCohort StudiesCoronary VesselsFemaleFollow-Up StudiesHospital MortalityHumansMaleMiddle AgedMyocardial InfarctionPatient DischargePercutaneous Coronary InterventionRisk AssessmentRisk FactorsShock, CardiogenicST Elevation Myocardial InfarctionTime FactorsTreatment OutcomeUnited StatesConceptsST-segment elevation myocardial infarctionMultivessel percutaneous coronary interventionMultivessel coronary artery diseasePercutaneous coronary interventionAcute myocardial infarctionCoronary artery diseaseCulprit vessel percutaneous coronary interventionCardiogenic shockHospital mortalityArtery diseaseMyocardial infarctionCohort studyPrimary outcomeHospital variationPCI strategyMedicare beneficiariesUnderwent multivessel PCISignificant hospital variationElevation myocardial infarctionSubset of patientsHigh-risk populationRecent evidenceHospital complicationsPCI useRevascularization practiceCOVID-19 infections and outcomes in a live registry of heart failure patients across an integrated health care system
Caraballo C, McCullough M, Fuery MA, Chouairi F, Keating C, Ravindra NG, Miller PE, Malinis M, Kashyap N, Hsiao A, Wilson FP, Curtis JP, Grant M, Velazquez EJ, Desai NR, Ahmad T. COVID-19 infections and outcomes in a live registry of heart failure patients across an integrated health care system. PLOS ONE 2020, 15: e0238829. PMID: 32997657, PMCID: PMC7526909, DOI: 10.1371/journal.pone.0238829.Peer-Reviewed Original ResearchConceptsHeart failure patientsIntegrated health care systemHeart Failure RegistryHealth care systemFailure patientsCOVID-19 infectionCare systemCOVID-19SARS-CoV-2 infectionReal-time registryRenin-angiotensin blockersRetrospective chart reviewCoronary artery diseaseRisk of deathCOVID-19 testingAngiotensin blockersMultiple comorbiditiesRespiratory failureChart reviewSymptomatic patientsArtery diseaseHeart failureComorbid conditionsPatient mortalityClinical management
2019
Acute Kidney Injury Among Older Patients Undergoing Coronary Angiography for Acute Myocardial Infarction: The SILVER-AMI Study
Dodson JA, Hajduk A, Curtis J, Geda M, Krumholz HM, Song X, Tsang S, Blaum C, Miller P, Parikh CR, Chaudhry SI. Acute Kidney Injury Among Older Patients Undergoing Coronary Angiography for Acute Myocardial Infarction: The SILVER-AMI Study. The American Journal Of Medicine 2019, 132: e817-e826. PMID: 31170374, PMCID: PMC6891160, DOI: 10.1016/j.amjmed.2019.05.022.Peer-Reviewed Original ResearchMeSH KeywordsActivities of Daily LivingAcute Kidney InjuryAge FactorsAgedAged, 80 and overCohort StudiesCoronary AngiographyDatabases, FactualFemaleGeriatric AssessmentHospital MortalityHospitalizationHumansKaplan-Meier EstimateLogistic ModelsMaleMyocardial InfarctionOdds RatioPrognosisProportional Hazards ModelsRisk AssessmentSeverity of Illness IndexSurvival AnalysisConceptsAcute kidney injuryAcute myocardial infarctionAge-related conditionsKidney injuryBody mass indexCoronary angiographyRisk factorsMyocardial infarctionOlder patientsMean ageAcute kidney injury risk factorsAcute Myocardial Infarction StudyAcute myocardial infarction cohortOlder adultsGlobal Outcomes criteriaMyocardial Infarction StudyInjury risk factorsParticipants' mean ageSILVER-AMI StudyMultivariable adjustmentComorbid diseasesHeart failureIndependent predictorsGeriatric conditionsMass index
2017
Use of Cardiac Resynchronization Therapy Among Eligible Patients Receiving an Implantable Cardioverter Defibrillator: Insights From the National Cardiovascular Data Registry Implantable Cardioverter Defibrillator Registry
Marzec LN, Peterson PN, Bao H, Curtis JP, Masoudi FA, Varosy PD, Bradley SM. Use of Cardiac Resynchronization Therapy Among Eligible Patients Receiving an Implantable Cardioverter Defibrillator: Insights From the National Cardiovascular Data Registry Implantable Cardioverter Defibrillator Registry. JAMA Cardiology 2017, 2: 561-565. PMID: 28122073, PMCID: PMC5814986, DOI: 10.1001/jamacardio.2016.5388.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overAtrial FibrillationBlack or African AmericanBundle-Branch BlockCardiac Resynchronization TherapyCardiac Resynchronization Therapy DevicesCerebrovascular DisordersCohort StudiesComorbidityDefibrillators, ImplantableDiabetes MellitusEthnicityFemaleHealth Facility SizeHeart FailureHospitalsHospitals, TeachingHumansHypertensionInsurance, HealthLung DiseasesMaleMedicaidMedicareMiddle AgedMortalityMyocardial IschemiaPractice Patterns, Physicians'RegistriesRegression AnalysisRetrospective StudiesUnited StatesWhite PeopleConceptsUse of CRTCardiac resynchronization therapyCRT-D useImplantable cardioverter defibrillatorGuideline-eligible patientsDevice implantationEligible patientsResynchronization therapyCardioverter defibrillatorNational Cardiovascular Data Registry Implantable Cardioverter Defibrillator RegistryNational Cardiovascular Data Registry ICD RegistryHeart failure-related eventsImplantable Cardioverter-Defibrillator RegistryCRT-D groupMulticenter retrospective cohortRisk-standardized ratesHospital-level variationCRT-D devicesHierarchical multivariable modelNonprivate insuranceRetrospective cohortSelect patientsICD RegistryGuideline recommendationsICD placementCardiac Outcomes After Ischemic Stroke or Transient Ischemic Attack
Young LH, Viscoli CM, Curtis JP, Inzucchi SE, Schwartz GG, Lovejoy AM, Furie KL, Gorman MJ, Conwit R, Abbott JD, Jacoby DL, Kolansky DM, Pfau SE, Ling FS, Kernan WN. Cardiac Outcomes After Ischemic Stroke or Transient Ischemic Attack. Circulation 2017, 135: 1882-1893. PMID: 28246237, PMCID: PMC5511545, DOI: 10.1161/circulationaha.116.024863.Peer-Reviewed Original ResearchConceptsAcute coronary syndromeType 1 myocardial infarctionTransient ischemic attackMyocardial infarctionCoronary syndromeInsulin resistanceIschemic attackIschemic strokeDiabetes mellitusSerum troponinAcute coronary syndrome episodeMean age 63 yearsAcute coronary syndrome eventIndependent clinical events committeeType 2 myocardial infarctionIRIS participantsImpact of pioglitazoneRecent cerebrovascular eventsRecent ischemic strokeClinical events committeeAge 63 yearsEffect of pioglitazoneSmall myocardial infarctionCoronary artery diseaseST-segment elevation
2015
Percutaneous Coronary Intervention Utilization and Appropriateness across the United States
Thomas MP, Parzynski CS, Curtis JP, Seth M, Nallamothu BK, Chan PS, Spertus JA, Patel MR, Bradley SM, Gurm HS. Percutaneous Coronary Intervention Utilization and Appropriateness across the United States. PLOS ONE 2015, 10: e0138251. PMID: 26379053, PMCID: PMC4575022, DOI: 10.1371/journal.pone.0138251.Peer-Reviewed Original ResearchConceptsAppropriate use criteriaHospital referral regionsPCI utilizationQuintile 5PCI ratesQuintiles 1PCI appropriatenessPercutaneous coronary intervention useMedicare Limited Data SetRisk-adjusted mortalityNCDR CathPCI RegistryElective PCICathPCI RegistryInappropriate indicationsPatient characteristicsStudy cohortAppropriate indicationsPCI proceduresHeart AssociationCardiovascular AngiographyStudy populationAmerican CollegeReferral regionsSubstantial geographic variationIntervention utilizationComparison of Inhospital Outcomes and Hospitalization Costs of Peripheral Angioplasty and Endovascular Stenting
Panaich SS, Arora S, Patel N, Patel NJ, Lahewala S, Solanki S, Manvar S, Savani C, Jhamnani S, Singh V, Patel SV, Thakkar B, Patel A, Deshmukh A, Chothani A, Bhatt P, Savani GT, Patel J, Mavani K, Bhimani R, Tripathi B, Mohamad T, Remetz MS, Curtis JP, Attaran RR, Grines C, Mena CI, Cleman M, Forrest JK, Badheka AO. Comparison of Inhospital Outcomes and Hospitalization Costs of Peripheral Angioplasty and Endovascular Stenting. The American Journal Of Cardiology 2015, 116: 634-641. PMID: 26096999, DOI: 10.1016/j.amjcard.2015.05.031.Peer-Reviewed Original ResearchConceptsLower amputation ratesInhospital mortalityPostprocedural complicationsHospitalization costsEndovascular stentingAmputation rateUtilization Project Nationwide Inpatient Sample databaseTwo-level hierarchical multivariateNationwide Inpatient Sample databaseComposite end pointPeripheral arterial diseaseHigher hospitalization costsAppropriate International ClassificationPeripheral endovascular interventionsInhospital outcomesSecondary outcomesPeripheral angioplastyPrimary outcomeArterial diseaseClinical outcomesStudy cohortNinth RevisionPatency ratesEndovascular interventionAngioplastyFrequency and Effects of Excess Dosing of Anticoagulants in Patients ≤55 Years With Acute Myocardial Infarction Who Underwent Percutaneous Coronary Intervention (from the VIRGO Study)
Gupta A, Chui P, Zhou S, Spertus JA, Geda M, Lorenze N, Lee I, Onofrio G, Lichtman JH, Alexander KP, Krumholz HM, Curtis JP. Frequency and Effects of Excess Dosing of Anticoagulants in Patients ≤55 Years With Acute Myocardial Infarction Who Underwent Percutaneous Coronary Intervention (from the VIRGO Study). The American Journal Of Cardiology 2015, 116: 1-7. PMID: 25937348, PMCID: PMC4466069, DOI: 10.1016/j.amjcard.2015.03.032.Peer-Reviewed Original ResearchMeSH KeywordsAdultAge DistributionAngioplasty, Balloon, CoronaryAnticoagulantsAntithrombinsBody Mass IndexCohort StudiesFemaleHemorrhageHeparinHirudinsHumansMaleMiddle AgedMyocardial InfarctionPeptide FragmentsPercutaneous Coronary InterventionPlatelet Glycoprotein GPIIb-IIIa ComplexPrevalenceRecombinant ProteinsRisk AssessmentRisk FactorsSex DistributionTreatment OutcomeUnited StatesConceptsPercutaneous coronary interventionGlycoprotein IIb/IIIa inhibitorsIIb/IIIa inhibitorsExcess dosingAcute myocardial infarctionCoronary interventionMultivariable analysisMyocardial infarctionUnderwent Percutaneous Coronary InterventionLower body weightOlder patientsYounger patientsUnfractionated heparinMedical recordsUnivariate analysisAnticoagulant agentsAnticoagulant drugsBody weightPatientsDosingYounger ageLogistic regressionYoung womenAnticoagulantsGender-based differences
2014
Temporal Trends in Patient Characteristics and Outcomes Among Medicare Beneficiaries Undergoing Primary Prevention Implantable Cardioverter-Defibrillator Placement in the United States, 2006–2010
Borne RT, Peterson PN, Greenlee R, Heidenreich PA, Wang Y, Curtis JP, Tzou WS, Varosy PD, Kremers MS, Masoudi FA. Temporal Trends in Patient Characteristics and Outcomes Among Medicare Beneficiaries Undergoing Primary Prevention Implantable Cardioverter-Defibrillator Placement in the United States, 2006–2010. Circulation 2014, 130: 845-853. PMID: 25095884, DOI: 10.1161/circulationaha.114.008653.Peer-Reviewed Original ResearchConceptsPrimary prevention ICD implantationDevice-related complicationsPatient characteristicsICD implantationICD RegistryNational Cardiovascular Data Registry ICD RegistryPrimary prevention implantable cardioverter-defibrillator placementConcomitant cardiac resynchronization therapyLeft ventricular ejection fractionImplantable cardioverter-defibrillator placementMultivariable hierarchical logistic regressionCardiac resynchronization therapy devicesCardiac resynchronization therapyVentricular ejection fractionResynchronization therapy devicesCommunity practice settingsSingle-lead deviceHierarchical logistic regressionClinical characteristicsOlder patientsEjection fractionResynchronization therapyPrimary preventionPatient populationHospital characteristicsRates of and Factors Associated With Infection in 200 909 Medicare Implantable Cardioverter-Defibrillator Implants
Prutkin JM, Reynolds MR, Bao H, Curtis JP, Al-Khatib SM, Aggarwal S, Uslan DZ. Rates of and Factors Associated With Infection in 200 909 Medicare Implantable Cardioverter-Defibrillator Implants. Circulation 2014, 130: 1037-1043. PMID: 25081281, DOI: 10.1161/circulationaha.114.009081.Peer-Reviewed Original ResearchConceptsICD infectionImplantable cardioverter defibrillator implantImplantable cardioverter-defibrillator infectionIndirect patient identifiersPrevious valve surgeryPrevious valvular surgeryChronic lung diseaseCardioverter-defibrillator implantICD-9 codesService claims dataCardioverter-defibrillator infectionComorbidity burdenManufacturers' advisoriesValvular surgeryEarly reinterventionValve surgeryAdverse eventsHospital dischargeRenal failureICD RegistryCerebrovascular diseaseImplant complicationsLung diseaseBiventricular ICDsMedicare patientsPredictors of an Inadequate Defibrillation Safety Margin at ICD Implantation Insights From the National Cardiovascular Data Registry
Hsu JC, Marcus GM, Al-Khatib SM, Wang Y, Curtis JP, Sood N, Parker MW, Kluger J, Lampert R, Russo AM. Predictors of an Inadequate Defibrillation Safety Margin at ICD Implantation Insights From the National Cardiovascular Data Registry. Journal Of The American College Of Cardiology 2014, 64: 256-264. PMID: 25034061, DOI: 10.1016/j.jacc.2014.01.085.Peer-Reviewed Original ResearchConceptsInadequate defibrillation safety marginDefibrillation safety marginSimple risk scoreAdverse eventsRisk scoreNew York Heart Association functional class IIIImplantable cardioverter defibrillator implantationNational Cardiovascular Data RegistrySecondary prevention indicationFunctional class IIIHospital adverse eventsCardioverter-defibrillator implantationIschemic heart diseaseLogistic regression modelsHospital mortalityPrevention indicationICD recipientsMale sexDefibrillation testingRenal dialysisHeart diseaseBiventricular deviceData registryLower riskGreater oddsPatterns and Outcomes of Red Blood Cell Transfusion in Patients Undergoing Percutaneous Coronary Intervention
Sherwood MW, Wang Y, Curtis JP, Peterson ED, Rao SV. Patterns and Outcomes of Red Blood Cell Transfusion in Patients Undergoing Percutaneous Coronary Intervention. JAMA 2014, 311: 836-843. PMID: 24570247, PMCID: PMC4276400, DOI: 10.1001/jama.2014.980.Peer-Reviewed Original ResearchConceptsPercutaneous coronary interventionRed blood cell transfusionReceipt of transfusionBlood cell transfusionAssociation of transfusionMyocardial infarctionTransfusion rateCell transfusionCoronary interventionTransfusion practiceHospital coronary artery bypass graft surgeryCoronary artery bypass graft surgeryHospital adverse cardiac eventsArtery bypass graft surgeryAdvanced renal dysfunctionPrior heart failureRisk-standardized ratesAdverse cardiac eventsBypass graft surgeryRetrospective cohort studyAcute coronary syndromeAdverse cardiac outcomesPrior myocardial infarctionBlood transfusion practicesCurrent transfusion practicesRisk Stratification for Long-Term Mortality After Percutaneous Coronary Intervention
Wu C, Camacho FT, King SB, Walford G, Holmes DR, Stamato NJ, Berger PB, Sharma S, Curtis JP, Venditti FJ, Jacobs AK, Hannan EL. Risk Stratification for Long-Term Mortality After Percutaneous Coronary Intervention. Circulation Cardiovascular Interventions 2014, 7: 80-87. PMID: 24425588, PMCID: PMC4121885, DOI: 10.1161/circinterventions.113.000475.Peer-Reviewed Original ResearchConceptsPercutaneous coronary interventionCox proportional hazards modelLong-term mortalityProportional hazards modelSimple risk scoreRisk of deathRisk scoreHazards modelCoronary interventionVital statusRisk factorsCoronary artery bypass graft surgeryArtery bypass graft surgeryExtreme body mass indexPoint-based risk scorePreprocedural risk factorsSimplified risk scoreUnstable hemodynamic stateBypass graft surgeryLow ejection fractionNational Death IndexBody mass indexPatients' vital statusSeparate risk factorsMultivessel disease
2013
Use of Remote Monitoring of Newly Implanted Cardioverter-Defibrillators
Akar JG, Bao H, Jones P, Wang Y, Chaudhry SI, Varosy P, Masoudi FA, Stein K, Saxon LA, Curtis JP. Use of Remote Monitoring of Newly Implanted Cardioverter-Defibrillators. Circulation 2013, 128: 2372-2383. PMID: 24043302, DOI: 10.1161/circulationaha.113.002481.Peer-Reviewed Original ResearchConceptsMedian odds ratioOdds ratioNational Cardiovascular Data Registry ICD RegistryRemote patient monitoringMultivariable logistic regressionHealth-related factorsImplanted cardioverter defibrillatorEligible patientsICD RegistryLack of enrollmentCurrent guidelinesCardioverter defibrillatorPatientsLogistic regressionLocal practice environmentMajor causeHealth insuranceSubsequent activationEnrollmentPractice environmentPatient monitoringPhysiciansActivationRPM systemSuccessful useQRS Duration, Bundle-Branch Block Morphology, and Outcomes Among Older Patients With Heart Failure Receiving Cardiac Resynchronization Therapy
Peterson PN, Greiner MA, Qualls LG, Al-Khatib SM, Curtis JP, Fonarow GC, Hammill SC, Heidenreich PA, Hammill BG, Piccini JP, Hernandez AF, Curtis LH, Masoudi FA. QRS Duration, Bundle-Branch Block Morphology, and Outcomes Among Older Patients With Heart Failure Receiving Cardiac Resynchronization Therapy. JAMA 2013, 310: 617-626. PMID: 23942680, DOI: 10.1001/jama.2013.8641.Peer-Reviewed Original ResearchMeSH KeywordsAge FactorsAgedAged, 80 and overBundle-Branch BlockCardiac Resynchronization TherapyCardiac Resynchronization Therapy DevicesCardiovascular DiseasesCohort StudiesElectrocardiographyFee-for-Service PlansFemaleHeart FailureHumansMaleMedicarePatient ReadmissionRetrospective StudiesRiskTreatment OutcomeUnited StatesConceptsLeft bundle branch blockCRT-D implantationCardiac resynchronization therapyHeart failure readmissionQRS durationCause mortalityICD RegistryResynchronization therapyUnadjusted ratesMedicare beneficiariesNational Cardiovascular Data Registry ICD RegistryClinical practiceBundle branch block morphologyCause readmission rateRetrospective cohort studyLonger QRS durationBundle branch blockService Medicare beneficiariesCause readmissionCohort studyCRT-defibrillatorOlder patientsReadmission ratesHeart failureClinical trialsAssociation of Single- vs Dual-Chamber ICDs With Mortality, Readmissions, and Complications Among Patients Receiving an ICD for Primary Prevention
Peterson PN, Varosy PD, Heidenreich PA, Wang Y, Dewland TA, Curtis JP, Go AS, Greenlee RT, Magid DJ, Normand SL, Masoudi FA. Association of Single- vs Dual-Chamber ICDs With Mortality, Readmissions, and Complications Among Patients Receiving an ICD for Primary Prevention. JAMA 2013, 309: 2025-2034. PMID: 23677314, PMCID: PMC3752924, DOI: 10.1001/jama.2013.4982.Peer-Reviewed Original ResearchConceptsDual-chamber ICDSingle-chamber devicesDevice-related complicationsPrimary preventionDual-chamber devicesICD RegistryNational Cardiovascular Data Registry ICD RegistryPropensity-matched cohortRetrospective cohort studyHeart failure readmissionRate of complicationsSudden cardiac deathMedicaid Services feePropensity-score matchingCause hospitalizationCause readmissionCohort studyHospital factorsCardiac deathHeart failureHospitalization outcomesRandomized trialsChamber ICDMAIN OUTCOMEHigh risk
2012
Low Body Mass Index but Not Obesity Is Associated With In‐Hospital Adverse Events and Mortality Among Implantable Cardioverter‐Defibrillator Recipients: Insights From the National Cardiovascular Data Registry
Hsu JC, Varosy PD, Bao H, Wang Y, Curtis JP, Marcus GM. Low Body Mass Index but Not Obesity Is Associated With In‐Hospital Adverse Events and Mortality Among Implantable Cardioverter‐Defibrillator Recipients: Insights From the National Cardiovascular Data Registry. Journal Of The American Heart Association 2012, 1: e003863. PMID: 23316325, PMCID: PMC3540679, DOI: 10.1161/jaha.112.003863.Peer-Reviewed Original ResearchConceptsBody mass indexNormal weight patientsFirst-time ICD recipientsWeight patientsAdverse eventsICD recipientsHospital deathHospital stayUnderweight patientsICD implantationObese patientsMass indexNational Cardiovascular Data Registry ICD RegistryAssociation of BMINational Cardiovascular Data RegistryLower body mass indexImplantable cardioverter defibrillator recipientsHierarchical multivariable logistic regressionMore periprocedural complicationsHospital adverse eventsMultivariable logistic regressionSudden cardiac deathPatient body habitusReal-world populationHospital complicationsElectrophysiology Studies in Patients Undergoing ICD Implantation: Findings from the NCDR®
CHENG A, WANG Y, BERGER RD, CALKINS H, BUXTON AE, CURTIS JP, LAMPERT R. Electrophysiology Studies in Patients Undergoing ICD Implantation: Findings from the NCDR®. Pacing And Clinical Electrophysiology 2012, 35: 912-918. PMID: 22670627, DOI: 10.1111/j.1540-8159.2012.03441.x.Peer-Reviewed Original ResearchConceptsICD implantationElectrophysiology studyEjection fractionSudden deathDe novo ICD implantationSecondary prevention ICD recipientsSudden death risk stratificationLeft ventricular ejection fractionImplantable cardioverter defibrillator implantationNarrow QRS intervalPrimary prevention ICDsDeath risk stratificationCardioverter-defibrillator implantationCongestive heart failureVentricular ejection fractionHigher ejection fractionHistory of syncopeMonomorphic ventricular tachycardiaLogistic regression analysisFuture ICD therapyHierarchical logistic regression analysisICD therapyClinical characteristicsComplication rateDefibrillator implantation