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SMS: Substrate Modification Study in Patients Getting an Implantable Cardioverter Defibrillator (ICD)

Substrate Modification Study in Patients Getting an ICD

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00170287
Acronym
SMS
Enrollment
116
Registered
2005-09-15
Start date
2002-05-31
Completion date
2011-08-31
Last updated
2025-07-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Tachycardia, Ventricular

Keywords

Unstable Ventricular Tachycardia

Brief summary

The present standard of care for the management of unstable ventricular tachycardia (VT) in the setting of chronic coronary artery disease is the placement of an implantable cardioverter defibrillator (ICD) after the initial episode, and radiofrequency ablation and/or antiarrhythmic medication in the event of recurrences causing frequent ICD interventions. The primary purpose of this randomized study is the assessment of recurrences of unstable VT in patients who undergo ICD implantation plus substrate ablation after the initial episode compared to patients who only undergo ICD implantation. Thus the primary purpose is an improvement in the quality of life. A decrease in mortality is not a primary purpose of this study.

Interventions

PROCEDUREICD Ablation plus VT-ablation

ICD-Therapy for the treatment of unstable VT´s plus catheter ablation for substrate modification

DEVICEICD Therapy

ICD Therapy for the Treatment of unstable VT´s

Sponsors

Medtronic
CollaboratorINDUSTRY
Medtronic Cardiac Rhythm and Heart Failure
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

* Coronary artery disease documented by coronary angiography. For the purpose of this study, coronary artery disease will be defined as the presence of a 50% or more diameter stenosis of the left main or of a 75% or more diameter stenosis of the left anterior descending, circumflex or right coronary arteries, or the history of a surgical or percutaneous revascularization procedure. * Left ventricular ejection fraction \< 40% as estimated by echocardiography or contrast ventriculography within the previous 30 days. * Clinical unstable VT without reversible factors (acute ischemia or antiarrhythmic medications as defined below). Unstable VT can have one of the following clinical presentations: * Hypotensive VT without major neurologic dysfunction; * Syncope; or * Cardiac arrest.

Exclusion criteria

* Age \< 18 years or \> 80 years * Protruding left ventricular (LV) thrombus on pre-ablation echocardiogram * Acute myocardial infarction within the preceding 2 months * Class IV New York Heart Association (NYHA) heart failure * Valvular heart disease or mechanical heart valve precluding access to the left ventricle * Unstable angina * Cardiac surgery within the past 2 months * Serum creatinine \> 220 mmol/L (2.5 mg/dL) * Thrombocytopenia or coagulopathy * Contraindication to heparin * Pregnancy * Acute illness or active systemic infection * Other disease process likely to limit survival to less than 12 months * Significant medical problem that, in the opinion of the principal investigator, would preclude enrollment into the study * Participation in another investigational study * Unwillingness to participate or lack of availability for follow-up

Design outcomes

Primary

MeasureTime frame
Time to the first documented recurrence of any sustained VT/ventricular fibrillation (VF) during the follow-up period12 Months

Secondary

MeasureTime frame
All appropriate ICD therapies (number of shocks, number of antitachycardia pacing therapies)12 Months
Quality of life12 Months
Number of hospital readmissions due to a cardiac indication12 Months
Severe clinical events12 Months

Countries

Denmark, Germany

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 27, 2026