Left Ventricular Dysfunction — Tricuspid Regurgitation Study
Citation(s)
1 Lin G, Nishimura R, Connolly H, Dearani J, Sundt T, Hayes D: Severe symptomatic tricuspid valve regurgitation due to permanent pacemaker or implantable cardioverter-defibrillator leads. JACC 2005; 45:1672-1675. 2. Leibowitz D, Rosenheck S, Pollak A, Geist M, Gilon D: Transvenous pacemaker leads do not worsen tricuspid regurgitation: a prospective echocardiographic study. Arrhythmias, Electrophysiology and Electrocardiography 2000; 93:74-77. 3. Kucukarslan N, Kirilmaz A, Ulusoy E, Yokusoglu M, Gramatnikovski N, Ozal E, Tatar H: Tricuspid insufficiency does not increase early after permanent implantation of pacemaker leads. J Card Surg 2006; 21:391-394. 4. Wilkoff B, Invesigators DT: The dual chamber and WI implantable defibrillator (DAVID) Trial: rationale, design, results, clinical implications and lessons for future trials. Cardiac Electrophysiol Review 2004; 7:468-472.
The Effect of Cardiac Pacing Leads on Tricuspid Regurgitation
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
