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1.
Med Sci Sports Exerc ; 35(9): 1477-85, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12972865

ABSTRACT

PURPOSE: Little information is available regarding peak and submaximal exercise performance in elderly heart failure (HF) patients, particularly in those with diastolic dysfunction (DD). Therefore, the purpose of this investigation was to compare exercise responses of elderly patients with HF due to either systolic dysfunction (SD) or DD, to age-matched healthy volunteers (HV). METHODS: Patients with chronic HF > or = 60 yr (N = 119) due to SD (N = 60) or primary DD (N = 59) underwent a maximal cycle ergometry test with expired gas analysis and venous lactate measurement. Twenty-eight HV > or = 60 yr served as a control group. Anaerobic threshold was determined by gas analysis (ATVEN) and by plasma lactate rise (ATLAC). RESULTS: Peak oxygen consumption (VO(2peak)) was significantly (P < 0.001) reduced in both SD and DD patients (13 +/- 0.4 vs 14 +/- 0.4 ml x kg(-1) x min(-1), respectively) versus HV (20 +/- 0.6 ml x kg(-1) x min(-1)). Peak heart rate was reduced in patients versus HV (131 +/- 3 bpm vs 145 +/- 4, respectively; P < or = 0.01), but heart rate at a given submaximal work rate was significantly lower (P < or = 0.01) in HV than in SD and DD patients. ATVEN of 11.8 +/- 0.3 ml x kg(-1) x min(-1) for HV was significantly higher than SD (8.9 +/- 0.2) and DD (9.2 +/- 0.3). Peak lactate concentration was 6.6 +/- 0.6 mmol x kg(-1) x l(-1) in HV and was significantly reduced in both SD and DD HF patients. ATVEN correlated well with ATLAC in HV and in DD patients, but not in SD patients. CONCLUSIONS: Submaximal and peak exercise performance are markedly altered in elderly HF patients compared with age-matched HV but do not appear to be different between SD and DD patients.


Subject(s)
Aging/physiology , Anaerobic Threshold , Exercise/physiology , Heart Failure/physiopathology , Aged , Diastole , Exercise Tolerance , Female , Humans , Lactic Acid/blood , Male , Middle Aged , Systole
2.
JAMA ; 288(17): 2144-50, 2002 Nov 06.
Article in English | MEDLINE | ID: mdl-12413374

ABSTRACT

CONTEXT: Many older patients with symptoms of congestive heart failure have a preserved left ventricular ejection fraction (LVEF). However, the pathophysiology of this disorder, presumptively termed diastolic heart failure (DHF), is not well characterized and it is unknown whether it represents true heart failure. OBJECTIVE: To assess the 4 key pathophysiological domains that characterize classic heart failure by systematically performing measurements in older patients with presumed DHF and comparing these results with those from age-matched healthy volunteers and patients with classic systolic heart failure (SHF). DESIGN AND SETTING: Observational clinical investigation conducted in 1998 in a general community and teaching hospital in Winston-Salem, NC. PARTICIPANTS: A total of 147 subjects aged at least 60 years. Fifty-nine had isolated DHF defined as clinically presumed heart failure, LVEF of at least 50%, and no evidence of significant coronary, valvular, or pulmonary disease. Sixty had typical SHF (LVEF < or =35%). Twenty-eight were age-matched healthy volunteer controls. MAIN OUTCOME MEASURES: Left ventricular structure and function, exercise capacity, neuroendocrine function, and quality of life. RESULTS: By echocardiography, mean (SE) LVEF was 60% (2%) in patients with DHF vs 31% (2%) in those with SHF and 54% (2%) in controls. Mean (SE) LV mass-volume ratio was markedly increased in patients with DHF (2.12 [0.14] g/mL) vs those with SHF (1.22 [0.14] g/mL) (P<.001) and vs controls (1.49 [0.17] g/mL) (P =.002). Peak oxygen consumption by expired gas analysis during cycle ergometry was similar in the DHF and SHF groups (14.2 [0.5] and 13.1 [0.5] mL/kg per minute, respectively; P =.40) and in both was markedly reduced compared with healthy controls (19.9 [0.7] mL/kg per minute) (P =.001 for both). Ventilatory anaerobic threshold was similar in the DHF and SHF groups (9.1 [0.3] and 8.7 [0.3] mL/kg per minute, respectively; P<.001) and in both was reduced compared with healthy controls (11.5 [0.4] mL/kg per minute) (P<.001). Norepinephrine levels were similar in the DHF (306 [64] pg/mL) and SHF (287 [62] pg/mL) groups (P =.56) and in both were markedly increased vs healthy controls (169 [80] pg/mL) (P =.007 and.03, respectively). Brain natriuretic peptide was substantially increased in both the DHF (56 [30] pg/mL) and the SHF (154 [28] pg/mL) groups compared with healthy controls (3 [38] pg/mL) (P =.02 and.001, respectively). Quality-of-life decrement score as assessed by the Minnesota Living with Heart Failure Questionnaire was substantially increased from the benchmark score of 10 in both groups (SHF: 43.8 [3.9]; DHF: 24.8 [4.4]). CONCLUSION: Patients with isolated DHF have similar though not as severe pathophysiologic characteristics compared with patients with typical SHF, including severely reduced exercise capacity, neuroendocrine activation, and impaired quality of life.


Subject(s)
Heart Failure/physiopathology , Ventricular Function, Left , Aged , Atrial Natriuretic Factor/blood , Catecholamines/blood , Diastole , Echocardiography, Doppler , Exercise Test , Female , Humans , Male , Middle Aged , Natriuretic Agents/blood , Natriuretic Peptide, Brain/blood , Physical Endurance , Quality of Life , Systole
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