What Will Heart Failure Clinical Trials Be Like?
The types of tests and assessments used in heart failure clinical trials will ultimately depend on the specific nature of the study and what aspects of cardiomyopathy are being investigated.
Provided below is a list of frequent procedures and tests used to evaluate the heart, heart functioning, and its impact on the body in general, many of which may be incorporated for use in clinical trials:
- Detailed physical exam and medical history.
- Cardiac catheterization: a procedure during which a long, thin, and flexible tube (i.e., catheter) is inserted into a blood vessel in the arm, upper thigh, or neck and threaded through until it reaches your heart. This allows doctors to perform diagnostic tests and treatments, as well as to evaluate blockages in the blood vessels.
- Chest x-ray
- Computed tomography (CT scan, or “CAT scan”) or magnetic resonance imaging (MRI) scans: these are non-invasive imaging procedures, similar to an x-ray, that allow doctors to take detailed pictures of your heart.
- Coronary angiography: a procedure during which a dye is injected into a vein in your arm and then viewed using a special x-ray machine, CT scanner, or MRI machine. This allows doctors to view the insides of the arteries that provide blood to your heart. Angiography may also be used to evaluate other blood vessels throughout the body.
- Echocardiography (“echo”): a painless procedure that uses ultrasound to create moving pictures of your heart, which allow doctors to see its size, shape, and how well it is working. During a procedure known as transesophageal echocardiography, a long, thin ultrasound probe is guided down the throat into the esophagus, which is directly behind the heart, in order to obtain more detailed pictures.
- Ejection fraction measurement: ejection fraction is a measurement of how well your heart pumps blood, and it is used to help classify heart failure and determine the most appropriate treatment.
- Electrocardiogram (EKG, or ECG): a straightforward and painless procedure that records the electrical activity of the heart. This test tells doctors how fast your heart is beating, the regularity (or irregularity) of your heart rhythm, and strength and timing of the electrical signals that constantly pass through the heart.
- Blood tests to evaluate the effectiveness or chemical properties of a medication, if you are participating in a clinical trial that is investigating the use of a new drug.
- Blood tests to look for chemical markers that indicate heart failure, such as markers of kidney and thyroid function, as well as the marker BNP.
- Nuclear heart scan: a test that uses a small but safe amount of a radioactive compound, injected into your body through a vein in the arm. This compound then travels to the heart and allows special cameras to take detailed pictures of the heart to evaluate 1) blood flow; 2) damaged heart muscle; and 3) pumping ability and efficiency.
- Stress test: a test performed while you exercise (usually by walking or running on a treadmill, or pedaling a stationary bicycle), which allows doctors to evaluate how your heart works during episodes of physical stress.
- Pain and quality of life assessments, as well as exercise diaries, may also be required in some studies, depending on the research question being studied.
In addition, your doctor will also classify your heart failure based on the results of these tests, and in accordance with one of two scales: the New York Heart Association (NYHA) scale, or the American College of Cardiology (ACC) scale.
The NYHA scale classifies heart failure in four classes (I-IV), with Class I being asymptomatic heart failure and Class IV being the most severe.
The ACC scale classifies heart failure using four letter-based stages (A-D). This system of classification is different from the NYHA system in that it includes a stage for individuals who have risk factors for, but no evidence of heart failure (Stage A). At the other end of the spectrum are Stage D patients, who are individuals with end-stage heart failure who require hospice care. The ACC scale is typically used by doctors to identify an individual’s risk factors and administer early and aggressive treatment to prevent or delay it.
Typical Protocol for Heart Failure Clinical Trials:
Specific examples of clinical trials for the various forms of cardiomyopathy might include the following:
- A study designed to compare the effects of a short-acting diuretic versus a long-acting diuretic in patients with heart failure to determine which one is most effective. Diuretics are medications that increase the rate at which urine forms. They are commonly used to treat conditions that result in the accumulation of excess fluid in the body, as well as to treat high blood pressure and various other conditions.
- A study designed to determine if patients who participate in a heart failure management program that provides tools to promote disease self-management (such as education, lifestyle modifications, and telephone support) can improve patients’ functional status and quality of life.
- A long-term study designed to evaluate the prevalence of comorbid breathing disorders in patients with heart failure to determine if such disorders: a) occur more frequently in a particular age group of patients; b) occur more often in men than women; and c) are associated with the weight of the patient.
- A randomized clinical trial to determine if standard therapy plus a new drug is superior to standard therapy plus placebo at reducing the risk of major cardiovascular events (including heart attack, stroke, and heart failure) in elderly patients with a history of specific cardiovascular risk factors.
A brief word about randomized trials and placebos:
Many clinical trials, to include Heart Failure Clinical Trials, involve the comparison of an investigational treatment to a “standard” treatment. Some studies determine which therapy a patient receives through a process known as randomization, in which patients are randomly assigned to receive either the investigational treatment or the standard treatment.
On occasion, a trial will investigate the use of a standard treatment plus a new drug compared to standard treatment plus a placebo (such as the fourth clinical trial example provided above). Placebos are inactive or “sham” treatments that are identical in appearance to the active treatment but have no therapeutic value.
Placebos are necessary to help determine if adverse effects that occur during the clinical trial are the result of the investigational treatment or due to some other factor. They also allow researchers to measure the effects of the active treatment and observe what would have happened without it.
In rare instances where no standard therapy exists, or when a new drug or therapy is being investigated, the investigational treatment might be compared to a placebo alone. In these types of trials, those patients who are randomized to the placebo group do not receive an active treatment.
It is important to know that placebo-only trials are only conducted when scientifically necessary and when patients have been adequately informed that they may end up receiving the placebo rather than the active treatment. It is very important to note, however, that no one should ever participate in such a placebo trial when there is a widely available and highly effective standard treatment already in existence for their particular disease or condition.
Trial Eligibility and Medical Information Needed;
The type of clinical trial you may be eligible for often depends on many factors, including your history of heart disease, treatment history, and a variety of clinical findings. Therefore, it is important to know many details pertaining to your specific diagnosis when searching for clinical trials. Examples of the details you may want to have on hand include:
- Your specific classification of heart failure (e.g., ACC stage C or NYHA Class II)
- Your prior history of heart disease
- Your prior history of treatment for heart disease (including any surgeries, procedures, and medications)
- Your current medications (including aspirin), vitamins, and dietary supplements
- Your most recent blood pressure, cholesterol, and triglyceride (i.e., lipid) levels
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