New Diagnostic Modalities in the Diagnosis of Heart Failure

15 Jan
2010

heart failure

Heart failure (HF) is one of the only that is increasing in prevalence in the United States. It is present in 6-10% of the population over the age of 65 and in 10% of those over the age of 80. Stated in another manner, if a person reaches the age of 40, he has a 20% chance of developing HF before death. Each month over one million people in the United States reach the age of 65 and for the first time in U.S. history, there are more people older than 65 years of age than younger than 65 years. HF morbidity and mortality is on the rise. Congestive HF (CHF) is the most frequent cause of hospitalization in patients over the age of 65, with three million patients having a primary or secondary discharge diagnosis of CHF yearly. One-year mortality ranges from 10-50% depending on the stage of the disease. These statistics will continue to grow as our population ages. HF knows no racial boundary; however, African-American patients are disproportionately affected with 3% of all adult black Americans afflicted, and they suffer higher morbidity and mortality rates. The magnitude of the problem now and, if not effectively addressed, in the future is apparent.

With the extent of the problem as outlined, it is especially alarming to concede that HF is correctly diagnosed initially in only 50% of affected patients. For example, patients who are elderly and/or obese may be treated for extended periods for a primary pulmonary disorder, when the accurate diagnosis is HF. The reasons for this are numerous, including the fact that some of the cardinal symptoms and signs of HF, such as dyspnea, edema, and exercise intolerance, have a broad differential diagnosis. Nevertheless, the need for an early and correct diagnosis is crucial. Studies have confirmed that an early diagnosis of HF leads to timely and appropriate treatment, resulting in a decrease in morbidity and mortality. In the survival and ventricular enlargement trial (SAVE) and the preventive arm of the study of left ventricular systolic dysfunction (SOLVD) trials, the use of angiotensin converting enzyme inhibitor (ACEI) delayed or prevented the onset of overt symptomatic HF in patients with asymptomatic left ventricular dysfunction (ALVD). The American Cardiology of College/American Heart Association (ACC/AHA) HF guidelines developed a classification system (Figure 1) to direct the focus not only on those with HF but importantly for those at risk of developing HF. The emphasis is on treating or preventing the risk factors that can lead to HF. The ACC/AHA HF guidelines do not recommend routine echocardiograms for people without symptoms or structural heart disease. This reluctance to endorse echocardiograms as a broad screening device for HF may principally be based on cost. A high number in the population would need to be screened resulting in a high cost to identify a few asymptomatic HF patients. The question has been asked how can asymptomatic HF patients be identified. A partial answer may be to screen those at high-risk with a cost-effective test, allowing for early and accurate diagnosis, early treatment, and preventing/decreasing morbidities. HF mortality rate is increasing despite medical advances and newer pharmacological agents. There is a need to prevent HF morbidities and reduce mortalities, which suggests there is a need to make an earlier and accurate HF diagnosis. The ACC/AHA HF classification scheme with “prevention of HF” to the “treatment of end-stage HF” is meant to complement rather than replace the old New York Heart Association (NYHA) functional classification.

Figure 1. Stages in the Evolution of Heart Failure

Figure 1. Stages in the Evolution of Heart Failure/

Recommended Therapy by Stage

Recommended Therapy by Stage

The history and physical examination are important steps in the assessment of HF and highly recommended in the ACC/AHA HF guidelines. The Heart Failure Society of America (HFSA) devised a screening tool to help clinicians make an accurate clinical diagnosis. The tool is based on the acronym FACES. Questions are asked about Fatigue, altered Activity or exercise pattern, Chest congestion, Edema of extremities and Shortness of breath. Patient assessment includes the history, a review of symptoms incorporating the concept of FACES, the physical examination, and the single most useful diagnostic test in the evaluation of patients with HF—the 2D echocardiogram coupled with Doppler flow studies. canadian pharmacy

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