Cardiac autonomic testing and treating heart disease. "A clinical perspective"

Abstract

Background: Coronary heart disease (CHD) is a major health concern, affecting nearly half the middle-age population and responsible for nearly one-third of all deaths. Clinicians have several major responsibilities beyond diagnosing CHD, such as risk stratification of patients for major adverse cardiac events (MACE) and treating risks, as well as the patient. This second of a two-part review series discusses treating risk factors, including autonomic dysfunction, and expected outcomes.

Methods: Therapies for treating cardiac mortality risks including cardiovascular autonomic neuropathy (CAN), are discussed.

Results: While risk factors effectively target high-risk patients, a large number of individuals who will develop complications from heart disease are not identified by current scoring systems. Many patients with heart conditions, who appear to be well-managed by traditional therapies, experience MACE. Parasympathetic and Sympathetic (P&S) function testing provides more information and has the potential to further aid doctors in individualizing and titrating therapy to minimize risk. Advanced autonomic dysfunction (AAD) and its more severe form cardiovascular autonomic neuropathy have been strongly associated with an elevated risk of cardiac mortality and are diagnosable through autonomic testing. This additional information includes patient-specific physiologic measures, such as sympathovagal balance (SB). Studies have shown that establishing and maintaining proper SB minimizes morbidity and mortality risk.

Conclusions: P&S testing promotes primary prevention, treating subclinical disease states, as well as secondary prevention, thereby improving patient outcomes through (1) maintaining wellness, (2) preventing symptoms and disorder and (3) treating subclinical manifestations (autonomic dysfunction), as well as (4) disease and symptoms (autonomic neuropathy).

Keywords: Cardiac autonomic neuropathy; Cardiovascular risk factors; Heart disease; Mortality.

Fig. 1 -

The influence of statin therapy on plasma-oxidized low-density lipoprotein (OxLDL) biomarkers and high-sensitivity C-reactive protein (CRP). apoB-IC = apolipoprotein B-100 immune complexes; CI = confidence interval; IC/apoB = immune complexes per apolipoprotein B-100; Ig = immunoglobin; Lp(a) = lipoprotein (a); MDA = malondialdehyde; MDA/apoB = malondialdehyde epitopes per apolipoprotein B-100; OxPL/apoB = oxidized phospholipid epitopes per apolipoprotein B-100. From The New England Journal of Medicine, Cohn JN, Tognoni G; Valsartan Heart Failure Trial Investigators. A randomized trial of the angiotensin-receptor blocker valsartan in chronic heart failure. Vol. 345, No. 23, pp. 1667-1675. Copyright © 2001 Massachusetts Medical Society (83). Adapted with permission from Massachusetts Medical Society. See text for details.