112
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Chronic Heart Failure and Exercise Intolerance: The Hemodynamic Paradox

      review-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Heart failure represents a major source of morbidity and mortality in industrialized nations. As the leading hospital discharge diagnosis in the United States in patients over the age of 65, it is also associated with substantial economic costs. While the acute symptoms of volume overload frequently precipitate inpatient admission, it is the symptoms of chronic heart failure, including fatigue, exercise intolerance and exertional dyspnea, that impact quality of life. Over the last two decades, research into the enzymatic, histologic and neurohumoral alterations seen with heart failure have revealed that hemodynamic derangements do not necessarily correlate with symptoms. This “hemodynamic paradox” is explained by alterations in the skeletal musculature that occur in response to hemodynamic derangements. Importantly, gender specific effects appear to modify both disease pathophysiology and response to therapy. The following review will discuss our current understanding of the systemic effects of heart failure before examining how exercise training and cardiac resynchronization therapy may impact disease course.

          Related collections

          Most cited references65

          • Record: found
          • Abstract: not found
          • Article: not found

          Heart failure.

            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Value of peak exercise oxygen consumption for optimal timing of cardiac transplantation in ambulatory patients with heart failure.

            Optimal timing of cardiac transplantation in ambulatory patients with severe left ventricular dysfunction is often difficult. To determine whether measurement of peak oxygen consumption (VO2) during maximal exercise testing can be used to identify patients in whom transplantation can be safely deferred, we prospectively performed exercise testing on all ambulatory patients referred for transplant between October 1986 and December 1989. Patients were assigned into one of three groups on the basis of exercise data: Group 1 (n = 35) comprised patients accepted for transplant (VO2 less than or equal to 14 ml/kg/min); group 2 (n = 52) comprised patients considered too well for transplant (VO2 greater than 14 ml/kg/min); and group 3 (n = 27) comprised patients with low VO2 rejected for transplant due to noncardiac problems. All three groups were comparable in New York Heart Association functional class, ejection fraction, and cardiac index (p = NS). Pulmonary capillary wedge pressure was significantly lower in group 2 than in either group 1 or 3 (p less than 0.05), although there was wide overlap. Patients with preserved exercise capacity (group 2) had cumulative 1- and 2-year survival rates of 94% and 84%, which are equal to survival levels after transplantation. In contrast, patients rejected for transplant (group 3) had survival rates of only 47% at 1 year and 32% at 2 years, whereas patients awaiting transplantation (group 1) had a survival rate of 70% at 1 year (both p less than 0.005 versus patients with VO2 greater than 14 ml/kg/min). All deaths in group 2 were sudden. By univariate and multivariate analyses, peak VO2 was the best predictor of survival, with only pulmonary capillary wedge pressure providing additional prognostic information. These data suggest that cardiac transplantation can be safely deferred in ambulatory patients with severe left ventricular dysfunction and peak exercise VO2 of more than 14 ml/min/kg.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Proinflammatory cytokine levels in patients with depressed left ventricular ejection fraction: a report from the Studies of Left Ventricular Dysfunction (SOLVD).

              This study sought to assess proinflammatory cytokine levels in patients in the studies of left ventricular dysfunction trial (SOLVD) in relation to both their New York Heart Association functional classification and their neurohormonal status before randomization. Elevated levels of tumor necrosis factor-alpha have been identified in 30% to 40% of patients with heart failure. However, it is unclear which subsets of patients with heart failure elaborate tumor necrosis factor-alpha. It is also unclear what the mechanism for the increased expression of proinflammatory cytokines is. Tumor necrosis factor-alpha and interleukin-6 levels were analyzed by enzymes-linked immunoassay using randomly selected plasma samples from patients in functional classes I to III who were enrolled in neurohormonal substudies of the SOLVD trial; age-matched healthy subjects served as the control group. Plasma levels of tumor necrosis factor-alpha (p < 0.001) were elevated in patients in functional classes I to III ([mean +/- SD] 1.95 +/- 0.54, 2.63 +/- 0.48, 6.4 +/- 1.9 pg/ml, respectively) compared with age-matched control subjects (0.75 +/- 0.05 pg/ml) and were progressively elevated in relation to decreasing functional status of the patient. Plasma levels of interleukin-6 (p < 0.001) were elevated in patients in functional classes I to III (3.3 +/- 0.55, 6.2 +/- 1.1, 5.22 +/- 0.9 pg/ml, respectively) compared with age-matched control subjects (1.8 +/- 0.5 pg/ml and were progressively elevated in relation to decreasing functional status of the patient. Cox proportional-hazards analysis showed that there was a trend toward significance between plasma tumor necrosis factor-alpha (p < 0.07) and survival, whereas there was no significant relation for plasma interleukin-6 (p < 0.72). Except for atrial natriuretic factor, which correlated weakly (r = 0.23, p = 0.04) with circulating tumor necrosis factor-alpha levels, there was no significance correlation between neurohormonal and proinflammatory cytokine levels. Circulating levels of proinflammatory cytokines increase in patients as their functional heart failure classification deteriorates. Moreover, activation of the neurohumoral axis is unlikely to completely explain the elaboration of proinflammatory cytokines in heart failure.
                Bookmark

                Author and article information

                Journal
                Curr Cardiol Rev
                CCR
                Current Cardiology Reviews
                Bentham Science Publishers Ltd.
                1573-403X
                1875-6557
                May 2008
                : 4
                : 2
                : 92-100
                Affiliations
                []Department of Medicine, Division of Cardiovascular Medicine, Duke University Medical Center, Durham, North Carolina, USA
                Author notes
                [* ]Address correspondence to this author at the Department of Medicine, Division of Cardiovascular Medicine, Duke University Medical Center, Box 31097, Durham, North Carolina 27713, USA; Tel: 919-403-7261; E-mail: nilss002@ 123456mc.duke.edu
                Article
                CCR-4-92
                10.2174/157340308784245757
                2779357
                19936283
                3119dbcb-f2f2-4836-9fa5-d89087a13cd9
                ©2008 Bentham Science Publishers Ltd.

                This is an open access article distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/2.5/) which permits unrestrictive use, distribution, and reproduction in any medium, provided the original work is properly cited.

                History
                : 18 September 2007
                : 23 November 2007
                : 3 December 2007
                Categories
                Article

                Cardiovascular Medicine
                cardiac,gender,exercise,chronic heart failure,skeletal muscle,resynchronization therapy (crt)

                Comments

                Comment on this article