Religiosity and religious coping in patients with cardiovascular disease: change over time and associations with illness adjustment.

Little is known about the longitudinal relationship between religiosity/spirituality (R/S) and patient physical and mental health in patients with cardiovascular disease. Forty-three patients with a first-time myocardial infarction or coronary artery revascularization bypass surgery completed measures of religiosity, religious coping, quality of life (QOL), and weight prior to a cardiac rehabilitation program and 1 and 2 years later. R/S changed over time; the direction of the change varied by type of R/S. Increases in religiosity were associated with increases in weight and QOL; increases in religious coping were associated with decreases in weight and increases in QOL.

Oxygen pulse is not predictive of stroke volume in heart failure.

AIM: Stroke volume (SV) is the major cardiovascular discriminator between those that are exercise trained versus untrained individuals and healthy individuals versus those with pathologic left ventricular dysfunction. Furthermore, since the increase in oxygen pulse (O(2)P) (O(2)P=VO(2)/HR?oxygen uptake/heart rate) that occurs with exercise is a function of SV and the arterial-venous oxygen difference (a-vO(2)), O(2)P has been demonstrated a reliable indicator of SV for healthy individuals. Although commonly used as a physiological and clinical marker of SV, the validity of O(2)P as an indicator of SV in patients with heart failure has not been investigated. METHODS: Thirty-one (23 men, 8 women) patients (age: 64+/-7.9; ejection fraction: 24+/-7.8) with chronic heart failure had cardiac output measured during steady-state workloads (25 watts and 75% VO(2peak)) upon entry and again at completion of 12 weeks of exercise training. Four patients were excluded due to clinical complications and 3 because of non-compliance; therefore, 24 patients completed the study. RESULTS: The relationships between SV and O2P are: 1) baseline: SV=11.1+4(O2P), SEE=11.8; r(2)=0.39 and 2) study completion: SV=25.1+2.3(O2P), SEE=12.7; r(2)=0.21. While SV did not increase after 25 watts, O2P continued to increase by 17%, respectively. In addition, there were no training effects on SV or O(2)P. As SV increased, O(2)P underpredicted measured SV. CONCLUSIONS: In patients with heart failure and poor left ventricular function, O(2)P is not recommended as a marker of the SV during exercise.

A review to develop an effective exercise training for heart failure patients.

The patient with heart failure relies on varied physiological adaptations to exercise training. Although, the cardiovascular adaptations may be limited, the patient with heart failure relies on changes in the pulmonary system as well as peripheral muscular adaptations. Therefore, the intent of this review is to outline effective exercise program design and to discuss the effects of exercise training on the patient with heart failure, including cardiovascular, pulmonary, and peripheral musculature adaptations. As a result of exercise training, patients with heart failure can improve their exercise capacity and quality of life, despite no or reduced improvement in central hemodynamics. Respiratory muscle endurance improves with exercise training which contributes to patients' increased exercise capacity, decreased breathlessness, and decreased perception of breathlessness. In addition, peripheral muscle adaptations result in an enhanced ability for oxygen extraction and utilization, a delayed onset of anaerobic metabolism during physical activity, and less fatigue as a result of physical activity and activities of daily living. Many of the physiological sequela associated with reduce functional ability in heart failure patients are correctable with exercise training. The practical implications (and maybe the most important to the patient) of these positive adaptations include less frequent rest periods, lesser overall fatigue, greater confidence to embark on physical tasks, maintenance of independence, and enhanced quality of life.

Measuring energy expenditure in cardiac patients using the Body Media Armband versus indirect calorimetry. A validation study.

AIM: The purpose of this study was to compare differences in energy expenditure using the newly developed SenseWear Armband body monitor to indirect calorimetry in cardiac rehabilitation patients. METHODS: Twenty-four (62+/-8.1 years) patients completed steady state exercise for 8 minutes on 4 modes of exercise (arm ergometry, treadmill walking, recumbent stepping and rowing ergometry). Total cumulative kilojoules were recorded simultaneously by indirect calorimetry and the SenseWear Armband. Statistical analyses assessed the degree of agreement between the 2 measurement methods and 3 different versions of the SenseWear software. RESULTS: The correlations between indirect calorimetry and version 2.2 of the SenseWear armband for arm and rowing ergometry, the treadmill and recumbent stepper were r=0.90, r=0.67, r=0 .80 and r=0.74, respectively. There were no between method differences during arm ergometry (p<1.000) and the recumbent stepper (p<0.102). Bland and Altman plots revealed the greatest spread of scores for the rower and the treadmill. Between method differences were minimal when using the preliminary cardiac software. The correlations for arm and rowing ergometry, the treadmill and recumbent stepper were r=0.90, r=0.84, r=0.78 and r=0.82, respectively. CONCLUSIONS: The accuracy of the BodyMedia SenseWear Armband appears to be exercise modality dependent in those with heart disease when using software developed for the general population. Therefore, the information should be interpreted cautiously, particularly during treadmill walking and rowing. Initial experiments with cardiac-focused software are promising, but preliminary.

Preoperative dobutamine stress echocardiography versus cardiac arteriography for risk assessment prior to renal transplantation.

Because coronary artery disease is the leading cause of death in patients with end-stage renal disease, we prospectively studied the prognostic value of dobutamine stress echocardiography (DSE) compared to coronary angiography (CA) as an evaluative tool. Thirty-three patients at high risk for coronary artery disease were selected from a cohort of 133 renal transplant candidates and underwent both DSE and CA. In this study, the value of DSE was found to exist in its strong negative predictive value (92%). A negative DSE coupled with a negative clinical cardiac evaluation was found to practicably exclude the necessity for CA. DSE can thus serve as a non-invasive, low cost screening test.

Body fat distribution's impact on physiologic outcomes during cardiac rehabilitation.

BACKGROUND: High waist-to-hip ratios (WHRs) predispose individuals to metabolic syndromes that may affect outcome responses to cardiac rehabilitation programs. METHODS: A total of 101 male patients who had undergone coronary artery revascularization surgery and completed 12 weeks of cardiac rehabilitation were divided into lower (LOWHR, n = 51) and higher (HIWHR, n = 50) waist-to-hip groups. Outcomes were measured at week 1 and week 12 of cardiac rehabilitation. RESULTS: Waist-to-hip ratio and body weight were greatest for HIWHR (P < 0.001) with no between-group differences in the amount of change from week 1 to 12. Triceps and subscapular skin-folds were greater for HIWHR (P < 0.001) with no difference in the amount of change between groups. Caloric expenditure during exercise class was higher for LOWHR (P = 0.022). Daily caloric expenditure was greater for LOWHR (P = 0.034) as was daily caloric intake (P < 0.001). There were no group differences for VO2peak and ventilatory anaerobic threshold (VAT) with nonsignificant trends for greater increases in LOWHR. CONCLUSIONS: Cardiac rehabilitation patients with greater WHRs expend less calories during exercise classes. To enhance overall caloric expenditure and obtain positive outcomes, cardiac rehabilitation professionals must emphasize greater activity with less sedentary time throughout the patients normal daily routine. The validity of using self-reported caloric intake and expenditure values in the cardiac rehabilitation population is questionable.

Cardiac rehabilitation without exercise tests for post-myocardial infarction and post-bypass surgery patients.

PURPOSE: To compare the progress of patients who were exercise tested before or during cardiac rehabilitation versus those patients who were not tested. METHODS: Eighty-eight (88) post-myocardial infarction patients and 141 post-bypass surgery patients had a symptom-limited exercise test before or during 12 weeks of cardiac rehabilitation. Another 125 post-myocardial infarction and 146 post-surgery patients were not tested. RESULTS: Caloric expenditure during class increased for the entire group (P < 0.001) from week 1 to week 12. Body weight decreased for the entire group as a result of cardiac rehabilitation (P < 0.001). Tricep skinfolds decreased for the entire group (P < 0.001) while subscapular skinfolds did not change (P = 0.28). The percent change from week 1 to week 12 for both groups was similar for all variables. No problems occurred during cardiac rehabilitation that required emergency medical management. CONCLUSIONS: Patients completing a 12-week cardiac rehabilitation program can be safely progressed in terms of their exercise capacity without an entry exercise test. This is desirable in a managed-care setting for reducing costs while maintaining effective patient care. Such factors as staff training and experience, institutional philosophy, patient referral patterns, and facility location must be considered before adopting a no-test policy.

Captopril reduces the VE/VCO2 ratio in myocardial infarction patients with low ejection fraction.

STUDY OBJECTIVES: To determine whether captopril (CAP) therapy had an effect on the minute ventilation/carbon dioxide output (VE/VCO2) ratio at submaximal levels of exercise in asymptomatic patients with reduced left ventricular function after myocardial infarction. DESIGN: Double blinded, randomized, prospective, repeated measures. PATIENTS AND INTERVENTIONS: One hundred thirty-five patients with left ventricular ejection fractions of < 40% were randomly assigned to a treatment group (CAP; n = 62) or a placebo group (PLC; n = 73). Subjects had cycle ergometer exercise tests at 2 to 6 months (T1), 10 to 14 months (T2), and > 22 months (T3) postmyocardial infarction. MEASUREMENTS: Oxygen uptake (VO2), VCO2, and VE were measured throughout each exercise test. Dependent variables were peak VO2 (VO2peak), the ventilatory anaerobic threshold (VAT), and the VE/VCO2 ratio measured at 30 W and at 75% VO2peak. RESULTS: VO2peak and VAT did not differ as a result of treatment (CAP vs PLC; p = 0.92 and 0.80) or over time (T1 vs T2 vs T3; p = 0.51 and 0.07). VE/VCO2 was significantly lower for CAP at 30 W (p = 0.05) and, although lower at 75% VO2peak, did not obtain statistical significance (p = 0.22). The between group differences were larger at T2 and T3 when compared with T1. CONCLUSIONS: CAP resulted in a reduced VE/VCO2 ratio during submaximal exercise. The reduced ventilation may permit patients to perform their normal activities of daily living at a lower perception of difficulty, reduce symptoms, and provide an improved quality of life.

Pulmonary manifestations of chronic heart failure.

These findings underscore the importance of understanding the complex interactions of multiple-organ systems in a chronic systemic disease state like congestive heart failure. The exaggerated ventilatory response in patients with heart failure is clearly multifactorial and it remains difficult to decipher whether this response results from or contributes to the sensation of dyspnea. Pulmonary dysfunction including ventilation-perfusion mismatching, decreased lung compliance, restriction, airway obstruction, decreased diffusion capacity, and decreases in respiratory muscle strength and endurance contribute to an inefficient breathing pattern and increased work of breathing. This is further compounded by the limited ability of the failing heart to meet the metabolic demands of the respiratory muscles, leading to under-perfusion and ischemia. This imbalance contributes to perceived dyspnea and exercise limitations. Understanding these physiologic cardiopulmonary interactions may lead to therapeutic modalities, such as respiratory muscle training, aimed at disrupting this intertwined cycle of events and improving functional capacity in patients with heart failure.

Exercise prescription when the guidelines do not work.

Because the current medical environment encourages a more conservative approach to resource use, "clinically unnecessary" exercise tests are being scrutinized and refused. This article's intent is not to debate the appropriateness of exercise tests for prescription purposes or suggest that programs should accept patients who have not been tested. These decisions are institutional specific. The intent is only to suggest an approach for those programs who feel it is safe and appropriate to accept patients who have not had an entry exercise test.

Oxygen uptake and cardiac output during progressive and constant load work in patients after acute myocardial infarction.

PURPOSE: Simultaneously measured oxygen uptake (VO2) and Doppler echocardiography could verify if an alteration in the VO2 response to progressive and constant load work is due to reduced cardiac output. METHODS: The study group consisted of nine patients after acute myocardial infarction (MI), five age-matched healthy subjects (HE), and five young well-trained subjects (WT). Each subject performed a progressive exercise test and two bouts of constant load work at power outputs equated to 10% below (W1) and 10% above (W2) their ventilatory thresholds. VO2 and cardiac output were measured continuously and simultaneously during the tests. RESULTS: VO2 was significantly reduced for the MI group during the initial stages of the progressive exercise test (P < .02) and remained lower throughout the entire test. During the first 60 seconds of constant load work (W2), VO2 was lower for MI (P < .05). At steady state exercise during W2, cardiac output was significantly less for MI (P < .05). VO2 for the MI group was more reliant on cardiac output during lower power outputs and differences in the arterial and venous O2 content (a-VO2 difference) during greater power outputs. CONCLUSIONS: Cardiac rehabilitation programs must be aware of this delayed VO2 and cardiac output response when setting training workloads or selecting the magnitude of the workload increments during progressive exercise tests.

Treadmill protocols for determination of maximum oxygen uptake in runners.

Four testing protocols were completed by each of 10 runners using a common speed for protocols 1 and 2 (P1 and P2), each runner's training pace for protocol 3 (P3) and a speed selected manually by the runner for protocol 4 (P4). Stages were increased by 2.5% grade every 2 min for each protocol except for P1, which had 1 min stages. There were no significant differences in maximum oxygen uptake (VO2 max) between protocols (P1, 65.0 +/- 5.6 ml.kg-1 min-1; P2, 64.5 +/- 5.3 ml.kg-1 min-1; P3, 66.2 +/- 3.9 ml.kg-1 min-1; P4, 64.7 +/- 5.8 ml.kg-1 min-1). Treadmill time was significantly less for P1 than for the other protocols. The rate of perceived exertion obtained at maximal exercise during P1 was less than that obtained during the other three protocols. Heart rate was significantly lower (P less than 0.05) at any level of submaximal VO2 during P3 than during the other protocols. We recommend a testing protocol using speeds approximating the runner's training pace and 1 min stages. This may result in lower perception of difficulty and HR throughout the test and shorter testing times.

Practical considerations in the testing of VO2max in runners.

Maximal oxygen intake (VO2max) may be the most physiologically significant and, therefore, the most commonly measured parameter in the physiological assessment of well trained runners. To insure valid and reliable VO2max values, there are a number of practical concerns that must be addressed. An exercise modality must be selected that activates the specific muscle mass and duplicates the motion utilised in the runners' training programme. Motorized treadmill running has been shown to allow the most efficient, valid and reproducible VO2max values in a controlled testing environment. A testing protocol must be used that is easily administered, comfortable for the runner, allows test completion within 10 minutes, uses grade increments at a constant speed, and is reproducible. Speeds should be selected that approximate the runner's training pace. The criterion for the attainment of VO2max include the levelling off of VO2 with an increase in work stage, the onset of extreme exhaustion, the respiratory exchange ratio exceeding 1.1, blood lactate levels approaching or exceeding 10 mmol/L, and ratings of perceived exertion of 19 or 20. Quality control in terms of standardisation of procedures and calibration and maintenance of equipment is essential for the minimisation of technological error. Measurement equipment must be affordable, dependable, easily calibrated, yield reproducible data, and be within the technical skill levels of the operating personnel.

Exercise and temperature effects on human sperm production and testosterone levels.

Five subjects exercised at an ambient temperature of 6.2 degrees C, five exercised at 37.7 degrees C, and five served as non-exercise controls. Each subject in the exercise groups performed one 45-min treadmill run a day for five consecutive days at heart rates that represented 80% of their maximum capacity. Sperm production was quantified the week preceding treatment and from 6-10 wk post-treatment. Plasma testosterone levels (PTL) were measured before each exercise test and immediately, 30 min, and 60 min after the first and fifth tests. The initial pre-exercise sample was taken immediately preceding the first test. Rectal temperature (Tre) and heart rate were monitored during all tests. No significant differences were found for sperm production. Plasma testosterone levels were 32.9% greater on the fourth and fifth day of testing than they were on day one (P less than 0.018). The 6.2 degrees C group (1202.7 ng%) had higher resting PTL than either the 37.7 degrees C (897.3 ng%) or the control (968.8 ng%) groups throughout the exercise period (P less than 0.001); PTL were 46.6% greater on day 5 than they were on day 1 for the 6.2 degrees C group (P less than 0.021). The change in Tre attributed to exercise was significantly greater in the 37.7 degrees C group (2.5 degrees C) when compared to the 6.2 degrees C group (1.1 degrees C; P less than 0.001). In summary, the changes in PTL and Tre that occurred as a result of 5 d of heavy exercise did not affect sperm production rates in humans.