Pulmonary oxygen uptake and heart rate kinetics during the six-minute walk test in transplant recipients.

Background: The effect of organ transplantation on arterial compliance, pulmonary oxygen uptake (VO2p) and heart rate kinetics during the 6-minute walk test (6-MWT) remains unknown.

Methods: Twenty-two thoracic (heart and/or lung) organ transplant recipients (TOTR, 51+/-12 years) and 30 abdominal (kidney, kidney-pancreas, or liver) organ transplant recipients (AOTR, 46+/-11 years) from the 2006 Canadian Transplant Games, and 37 healthy controls (HC) completed a 6-MWT. VO2p, heart rate kinetics, and arterial compliance were determined.

A prediction model for estimating pulmonary oxygen uptake during the 6-minute walk test in organ transplant recipients.

We developed a multivariate prediction equation for estimating the highest obtainable pulmonary oxygen uptake (VO2p) during the 6-minute walk test (6-MWT) in 54 organ transplant recipients: heart/heart-double-lung (n=14), kidney/kidney-pancreas (n=16), liver (n=14), double lung (n=8), bone marrow (n=2). They were of age, 48+/-12 years. Participants performed a 6-MWT during which expired gases were collected and analyzed with a portable metabolic system interfaced with a wireless heart rate monitor.

Cardiovascular reserve and risk profile of postmenopausal women after chemoendocrine therapy for hormone receptor--positive operable breast cancer.

Purpose. To examine cardiovascular function and risk profile of postmenopausal women treated with chemoendocrine therapy (CET) for hormone receptor-positive operable breast cancer. Methods.

Early breast cancer therapy and cardiovascular injury.

Although recent advances in curative-intent therapies are beginning to produce significant survival gains in early breast cancer, these improvements may ultimately be attenuated by increased risk of long-term cardiovascular mortality. This paper reviews emerging evidence on the cardiovascular effects of breast cancer adjuvant therapy and proposes a new entity that we have labeled the "multiple-hit" hypothesis. The evidence that lifestyle modification, especially exercise therapy, may mitigate these adverse effects is also reviewed.

Impaired pulmonary oxygen uptake kinetics and reduced peak aerobic power during small muscle mass exercise in heart transplant recipients.

We examined peak and reserve cardiovascular function and skeletal muscle oxygenation during unilateral knee extension (ULKE) exercise in five heart transplant recipients (HTR, mean +/- SE; age: 53 +/- 3 years; years posttransplant: 6 +/- 4) and five age- and body mass-matched healthy controls (CON). Pulmonary oxygen uptake (Vo(2)(p)), heart rate (HR), stroke volume (SV), cardiac output (Q), and skeletal muscle deoxygenation (HHb) kinetics were assessed during moderate-intensity ULKE exercise. Peak exercise and reserve Vo(2)(p), Q, and systemic arterial-venous oxygen difference (a-vO(2diff)) were 23-52% lower (P < 0.

Effects of presurgical exercise training on cardiorespiratory fitness among patients undergoing thoracic surgery for malignant lung lesions.

Background: To determine the effects of preoperative exercise training on cardiorespiratory fitness in patients undergoing thoracic surgery for malignant lung lesions.

Methods: Using a single-group design, 25 patients with suspected operable lung cancer were provided with structured exercise training until surgical resection. Exercise training consisted of 5 endurance cycle ergometry sessions per week at intensities varying from 60% to 100% of baseline peak oxygen consumption (VO(2 peak)).

A meta-analysis of the effect of exercise training on left ventricular remodeling in heart failure patients: the benefit depends on the type of training performed.

Objectives: The aim of this study was to determine the effect of exercise training and type of exercise (aerobic vs. strength vs. combined training) on left ventricular (LV) remodeling in heart failure (HF).

Relation of etiology of heart failure (ischemic versus nonischemic) before transplantation to delayed pulmonary oxygen uptake kinetics after heart transplantation.

The effect that pretransplantation heart failure cause has on pulmonary oxygen uptake (VO2p) kinetics and peak aerobic power (VO2peak) in heart transplant recipients (HTRs) has not been studied. We examined VO2p kinetics and VO2peak in HTRs with previous ischemic heart failure (I-HTRs; n=16, mean age 64+/-6 years) or nonischemic heart failure (NI-HTRs; n=13, mean age 50+/-12 years). HTRs performed an incremental exercise (VO2peak) test and a constant work rate submaximal exercise (VO2p kinetics) test.

Cardiovascular risk profile of patients with HER2/neu-positive breast cancer treated with anthracycline-taxane-containing adjuvant chemotherapy and/or trastuzumab.

Purpose: To evaluate the cardiovascular risk profile of a subset of patients with early-stage breast cancer treated with adjuvant taxane-anthracycline-containing chemotherapy and/or trastuzumab (Herceptin).

Experimental Design: Twenty-six patients with breast cancer (mean, 20 months postchemotherapy) and 10 healthy age-matched women were studied. We measured 14 metabolic and vascular established cardiovascular disease (CVD) risk factors, body mass index, cardiorespiratory fitness, and left ventricular systolic function.

Cardiovascular consequences of high-performance aircraft maneuvers: implications for effective countermeasures and laboratory-based simulations.

The gravitational stress encountered by pilots of high-performance aircraft can cause dramatic shifts in blood volume and circulatory pressure, thus placing the cardiovascular system under significant stress, sometimes resulting in loss of consciousness due to cerebral under-perfusion. Since pilots experience both increased and decreased gravitational stress in high-risk environments, it is important not only to examine the cardiovascular effects of altered gravitational exposure, but also to create effective countermeasures that will increase pilot safety. In this review, we discuss the cardiovascular consequences of rapid changes in gravitational forces.

Central haemodynamics and peripheral muscle function during exercise in patients with chronic heart failure.

In this narrative review of the current literature, we examine the central and peripheral mechanisms responsible for the exercise intolerance of chronic heart failure and highlight briefly the benefits of exercise training in the treatment of this debilitating disorder. Specifically, we identify the common finding of reduced cardiac output reserve during exercise conditions leading to decreased exercise tolerance. We also reveal that the stroke volume response to exercise varies depending on the individual patient, the presence of mitral regurgitation, and the aetiology of heart failure.

The potential role of the pericardium on diastolic filling in endurance-trained athletes under conditions of physiological stress.

In this review, we examine the growing body of evidence suggesting that the pericardium plays an important role in modulating cardiac function during conditions of physiological stress. Specifically, we discuss the effects of the pericardium on left ventricular filling and compliance. Furthermore, we reveal that there is increasing evidence to support the contention that the pericardium is capable of adaptation in response to volume loading.

The evaluation of cardiac function across the health spectrum under diverse conditions of physiological stress: introduction.

In this paper we introduce 3 papers resulting from a symposium evaluating cardiac function across the health spectrum under varied conditions of physiological stress. Esch et al. (Appl.

The effect of high-intensity rowing and combined strength and endurance training on left ventricular systolic function and morphology.

Combined strength and endurance training may result in alterations in left ventricular (LV) systolic function and morphology, however, the acute effect of high-intensity rowing exercise and concurrent training-induced adaptations on LV systolic function are not well known. The purpose of this investigation was to assess LV systolic function before and after a simulated 2000-m rowing race on a Concept II rowing ergometer and evaluate these adaptations following 10 weeks of concurrent strength and endurance training. Furthermore, resting LV morphology was assessed prior to and following the 10-week training program.

Diastolic ventricular interactions in endurance-trained athletes during orthostatic stress.

Enhanced left-ventricular (LV) compliance is a common adaptation to endurance training. This adaptation may have differential effects under conditions of altered venous return. The purpose of this investigation was to assess the effect of cardiac (un)loading on right ventricular (RV) cavity dimensions and LV volumes in endurance-trained athletes and normally active males.

Safety and feasibility of cardiopulmonary exercise testing in patients with advanced cancer.

Purpose: The use of cardiopulmonary exercise testing (CPET) is increasing in many areas of disease management, the clinical utility of this procedure in patients with advanced cancer remains to be determined. Accordingly, we conducted a pilot study to comprehensively evaluate the safety and feasibility of CPET in 85 patients diagnosed with inoperable non-small cell lung cancer (NSCLC) or metastatic breast cancer (MBC).

Methods: Using a cross-sectional design, consecutive patients with histologically or cytologically confirmed inoperable NSCLC or MBC were screened for eligibility by their attending oncologist.

Sex differences in left ventricular function and beta-receptor responsiveness following prolonged strenuous exercise.

Sex differences in neuroendocrine and metabolic responses to prolonged strenuous exercise (PSE) have been well documented. The aim of this investigation was to examine sex differences in left ventricular function and cardiac beta-receptor responsiveness following a single bout of PSE. Nine male and eight female triathletes were examined during three separate sessions: before, immediately after, and 24 h following a half-ironman triathlon using dobutamine stress echocardiography.

Impaired arterial compliance and aerobic endurance in kidney transplant recipients.

Background: Cardiovascular disease is the leading cause of morbidity and mortality in kidney transplant recipients (KTR). Two risk factors for cardiovascular disease that have not been examined in this population are arterial compliance and aerobic capacity. The primary objective was to determine small and large artery compliance and aerobic endurance in KTR.

Helium-hyperoxia, exercise, and respiratory mechanics in chronic obstructive pulmonary disease.

Rationale: Hyperoxia and normoxic helium independently reduce dynamic hyperinflation and improve the exercise tolerance of patients with chronic obstructive pulmonary disease (COPD). Combining these gases could have an additive effect on dynamic hyperinflation and a greater impact on respiratory mechanics and exercise tolerance.

Objective: To investigate whether helium-hyperoxia improves the exercise tolerance and respiratory mechanics of patients with COPD.

Regional muscle oxygenation differences in vastus lateralis during different modes of incremental exercise.

Background: Near infrared spectroscopy (NIRS) is used to assess muscle oxygenation (MO) within skeletal muscle at rest and during aerobic exercise. Previous investigations have used a single probe placement to measure MO during various forms of exercise. However, regional MO differences have been shown to exist within the same muscle which suggests that different areas of the same muscle may have divergent MO.

Effect of acute increases in pulmonary vascular pressures on exercise pulmonary gas exchange.

The purpose of this study was to determine the effect of acute increases in pulmonary vascular pressures, caused by the application of lower-body positive pressure (LBPP), on exercise alveolar-to-arterial PO2 difference (A-aDO2), anatomical intrapulmonary (IP) shunt recruitment, and ventilation. Eight healthy men performed graded upright cycling to 90% maximal oxygen uptake under normal conditions and with 52 Torr (1 psi) of LBPP. Pulmonary arterial (PAP) and pulmonary artery wedge pressures (PAWP) were measured with a Swan-Ganz catheter.

Does fitness level modulate the cardiovascular hemodynamic response to exercise?

Subjects with greater aerobic fitness demonstrate better diastolic compliance at rest, but whether fitness modulates exercise cardiac compliance and cardiac filling pressures remains to be determined. On the basis of maximal oxygen consumption (VO2max), healthy male subjects were categorized into either low (LO: VO2max=43+/-6 ml.kg-1.

Supervised exercise training improves aerobic capacity and muscle strength in older women with heart failure.

Background: The effect that supervised or unsupervised exercise training has on aerobic capacity (peak oxygen consumption [VO2peak]), muscle strength and quality of life in older women with heart failure remains unknown.

Objective: To examine the effect of six months (three months supervised followed by three months unsupervised) of aerobic training (AT) or combined aerobic and strength training (CAST) on VO2peak, muscle strength and quality of life in older women with heart failure.

Methods: Twenty older women (mean age +/- SD, 72+/-8 years) with clinically stable heart failure were randomly assigned to AT (n=10) or CAST (n=10).

Arterial compliance in young children: the role of aerobic fitness.

Background: Reduced arterial compliance is reflective of vascular dysfunction, which promotes the atherosclerotic process, and is therefore an important predictor of vascular disease. In adults, obesity, age, aerobic fitness, oestrogens and race influence arterial compliance. Although stature and blood pressure are known to influence compliance in children, other determinants are less established.