View clinical trials related to Cardiomyopathies.
Filter by:The purpose of this study was to evaluate the benefit of biventricular pacing in patients with heart failure who were receiving optimal pharmacological therapy, and who were either with or without an ICD indication
This prospective study will evaluate in patients, fulfilling implant criteria for Cardiac Resynchronisation Therapy (CRT) implant, the optimal atrial contribution to the resynchronised ventricles in the event of right atrial pacing.
Patients hospitalized for treatment of decompensated heart failure (CHF) are at risk for prolonged length of stay (LOS) and frequent readmissions. Renal dysfunction and diuretic resistance contribute to this risk, particularly if renal dysfunction worsens during CHF treatment. Brain natriuretic peptide (BNP) is a hormone of myocardial cell origin with well-defined physiological effects which include arterial and venous vasodilation, suppression of adverse neurohumoral systems and favorable effects on renal hemodynamics and sodium excretion. Recombinant human BNP (Natrecor) is approved by the FDA for treatment of decompensated CHF as it has been demonstrated to lower filling pressures and improve symptoms. While clinical trials and the FDA support the use of BNP as adjuvant therapy in decompensated CHF, the extent of its efficacy in improving non-hemodynamic CHF parameters has not been fully defined. The objective of this clinical practice protocol is to determine whether use of BNP in addition to standard therapy, will preserve renal function and facilitate diuresis in patients with CHF and mild-moderate renal impairment (creatinine clearance > 20 but < 60 ml/min) as compared to standard therapy alone. Patients admitted to the Mayo Heart Failure Service who meet entrance criteria will be randomized to standard clinical practice with or without a 48 hour infusion of BNP. The primary endpoints will be indices of renal function and diuretic response at 1, 2 and 3 days and at discharge. Secondary endpoints will be neurohumoral function, LOS and 30-day readmission rate.
This observational study will provide data (variations in ventricular size and function) that are essential to designing and conducting clinical trials. In addition, the study will evaluate intra- and inter-study variability seen in echocardiography.
The purpose of this study is to determine the safety and effectiveness of the Thoratec HeartMate II Left Ventricular Assist System (LVAS) as Destination Therapy in end-stage heart failure patients who do not qualify for cardiac transplantation. The Destination Therapy indication for use was approved by FDA on January 20, 2010 (ref. PMA P060040/S005).
The purpose of this study is to determine the safety and effectiveness of the Thoratec HeartMate II Left Ventricular Assist System (LVAS) as a bridge to cardiac transplantation in end-stage heart failure patients who are listed for cardiac transplant but are at imminent risk of dying. The HeartMate II LVAS was approved by the US FDA on April 21, 2008, as a bridge to cardiac transplantation (reference PMA P060040). It was approved for commercial distribution in Canada on May 20, 2009 (reference Medical Device Licence #79765). Patients enrolled into the clinical trial will continue to be followed until all have reached a clinical outcome.
This study will examine the usefulness of a new test called an isoproterenol challenge in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and family members who may have the disease but do not have clear-cut evidence of it. ARVC is a rare condition that runs in families. Heart muscle is replaced with fatty, scar-like tissue, especially in the right ventricle (lower pumping chamber of the heart), and can sometimes extend to the left ventricle (the main pumping chamber). The fat can interfere with the heartbeat, producing abnormal heart rhythms, such as ventricular tachycardia (VT) - a very fast heartbeat that can cause sudden death, especially in young people. Isoproterenol is a drug that increases heart rate and heart muscle contractions. In isoproterenol challenge, subjects are given increasing doses of the drug through a catheter (see details below) to try to produce an abnormal heart rhythm. ARVC is hard to diagnose with current tests. This study will see if isoproterenol challenge provokes VT in patients with the disease and can confirm the diagnosis; if it can detect the disease in family members better than currently available tests; and if it provokes abnormal rhythms in healthy control subjects. In addition, the study will explore the genetics of ARVC and determine whether infection could contribute to its development. Patients with ARVC, their family members, and normal volunteers 18 years of age and older may be eligible for this study. Candidates are screened with a medical history and physical examination, electrocardiogram (EKG), treadmill and bicycle exercise testing, and an echocardiogram (ultrasound test of the heart). Participants undergo the following tests and procedures: - Blood tests - Blood is collected to study the genetics of ARVC, to test for evidence of old infections, and to measure brain natriuretic peptide - a hormone that can increase with development of heart failure. - Heart magnetic resonance imaging (MRI). This test looks at heart structure and function. MRI uses a magnetic field and radio waves to produce images of body tissues and organs. The subject lies on a table that is moved into the scanner (a narrow cylinder), wearing earplugs to muffle loud knocking sounds that occur during the scanning process. At some time during the test, the subject is given a contrast agent called gadolinium through a catheter (thin, flexible tube) in a vein to improve the scan pictures. The scan time varies from 30 to 90 minutes, with most scans lasting 60 minutes. (Control subjects do not undergo MRI.) - Isoproterenol challenge. Subjects are given increasing doses of isoproterenol through a catheter until the heart rate reaches 100 to 120 beats per minute for no more than 1 hour. A special EKG records heart rhythm during the test and an echocardiogram records right and left ventricular function. - QRST surface mapping EKG. This special EKG, done with 64 or 120 leads, maps abnormalities of heart rhythm and cardiac conduction during the isoproterenol challenge. These tests are like a regular EKG, except that more leads are placed on the chest, and on the back as well. Patients and family members who wish to have follow-up visits may return to the NIH Clinical Center once a year for 5 years for guidance about therapy based on clinical considerations and new information or investigations.
This study will examine how heart stiffness and a weak atrium affect exercise capacity and symptoms in patients with hypertrophic cardiomyopathy (HCM). The atrium is the booster pumping chamber of the heart that helps the ventricle (main pumping chamber), to fill properly. HCM is an inherited disease in which the ventricle becomes thickened and, in some patients, stiff. The stiffness makes it difficult for the ventricle to fill and empty, causing breathing difficulty, fatigue, and reduced exercise capacity. Scar formation and a weakened atrium can cause the heart to stiffen. Information gained from this study may guide doctors in prescribing medicines to reduce scarring or improve atrial function. Patients 21 years of age and older with hypertrophic cardiomyopathy may be eligible for this study. Candidates will be screened with a medical history and physical examination, electrocardiogram (EKG), blood tests, Holter monitor, and echocardiogram. A Holter monitor is a device about the size of a Walkman that is connected to three wires that are attached to the chest. It is worn for 24 hours to provide continuous monitoring of heart rhythm. An echocardiogram uses a small probe that emits sound waves to produce images of the heart. The probe is moved across the chest and the reflection of the sound waves from the chambers of the heart produce images showing the heart's thickness and function. Participants will undergo the following tests and procedures over 3 days: - Physical examination and echocardiogram. - Intravenous cannula insertion: A plastic tube is inserted into an arm vein for collecting blood samples to measure substances that the heart and circulatory system release at rest and during exercise. - Impedance cardiography: A small current of electricity is passed across the chest and electrodes similar to those used for an EKG test are placed to measure blood flow in the area of the current. - Pulmonary artery catheterization: A catheter (plastic tube) is inserted into a vein either in the arm, under the collarbone, or in the neck and advanced to the right atrium and ventricle. The catheter remains in place during the echocardiogram tilt and bicycle exercise tests (see below). - Echocardiogram tilt test: The patient lies flat on a table. After a few minutes, the table is tilted so that the patient's head is just above his or her feet for a short while, then is positioned flat again, and then tilted so the feet are just above the head. Echocardiographic measurements and blood samples are taken at intervals to examine heart function during changes in posture. - Echocardiogram bicycle stress test: The patient exercises for as long as possible on a bicycle-like machine while lying on his or her back. Echocardiographic measurements and blood samples are taken at intervals during the test. - Treadmill stress test: The patient runs for as long as possible on a treadmill that increases in difficulty. The patient wears a facemask or mouthpiece through which small amounts of gases are added in order to measure the ability of the heart and lung to increase their effectiveness with exercise. - Digoxin loading: Only patients who demonstrate limited exercise capacity and for whom digoxin is not a risk will undergo this procedure. A medicine that makes the heart contract more strongly, digoxin is used to treat certain heart abnormalities. Patients are given doses of either digoxin or placebo (a look-alike injection with no active ingredient) at 4-hour intervals over a 24-hour period and then repeat the tilt test and the bicycle and treadmill exercise tests
In addition to medical treatment for heart failure (HF), a variety of non-pharmacological interventions have been demonstrated to benefit these patients. Some of these include systems for weight monitoring and medication reminders, exercise programs, and individually tailored evaluation and treatment plans with dietitians, social workers, psychologists, and nurse case managers. While many of these approaches have been shown to increase adherence to medication guidelines and result in decreased health care utilization, most rely heavily on a large team of specialized health care providers. It remains unknown whether or not an intervention with a lower intensity of specialized care using sophisticated automated computer tracking and Interactive Voice Response (IVR) techniques can impact the care of HF patients.
To identify new dilated cardiomyopathy genes by genetic linkage and mutational analyses.