E xercise testing remains a remarkably durable and versatile tool that provides valuable diagnostic and prognostic information regarding patients with cardiovascular and pulmonary disease. Exercise testing has been available for more than a half century and, like many other cardiovascular procedures, has evolved in its technology and scope. When combined with exercise testing, adjunctive imaging modalities offer greater diagnostic accuracy, additional information regarding cardiac structure and function, and additional prognostic information. Similarly, the addition of ventilatory gas exchange measurements during exercise testing provides a wide array of unique and clinically useful incremental information that heretofore has been poorly understood and underutilized by the practicing clinician. The reasons for this are many and include the requirement for additional equipment (cardiopulmonary exercise testing [CPX] systems), personnel who are proficient in the administration and interpretation of these tests, limited or absence of training of cardiovascular specialists and limited training by pulmonary specialists in this technique, and the lack of understanding of the value of CPX by practicing clinicians.Modern CPX systems allow for the analysis of gas exchange at rest, during exercise, and during recovery and yield breath-by-breath measures of oxygen uptake (V O 2 ), carbon dioxide output (V CO 2 ), and ventilation (V E). These advanced computerized systems provide both simple and complex analyses of these data that are easy to retrieve and store, which makes CPX available for widespread use. These data can be readily integrated with standard variables measured during exercise testing, including heart rate, blood pressure, work rate, electrocardiography findings, and symptoms, to provide a comprehensive assessment of exercise tolerance and exercise responses. CPX can even be performed with adjunctive imaging modalities for additional diagnostic assessment. Hence, CPX offers the clinician the ability to obtain a wealth of information beyond standard exercise electrocardiography testing that when appropriately applied and interpreted can assist in the management of complex cardiovascular and pulmonary disease.

Obesity has reached global epidemic proportions in both adults and children and is associated with numerous comorbidities, including hypertension (HTN), type II diabetes mellitus, dyslipidemia, obstructive sleep apnea and sleep-disordered breathing, certain cancers, and major cardiovascular (CV) diseases. Because of its maladaptive effects on various CV risk factors and its adverse effects on CV structure and function, obesity has a major impact on CV diseases, such as heart failure (HF), coronary heart disease (CHD), sudden cardiac death, and atrial fibrillation, and is associated with reduced overall survival. Despite this adverse association, numerous studies have documented an obesity paradox in which overweight and obese people with established CV disease, including HTN, HF, CHD, and peripheral arterial disease, have a better prognosis compared with nonoverweight/nonobese patients. This review summarizes the adverse effects of obesity on CV disease risk factors and its role in the pathogenesis of various CV diseases, reviews the obesity paradox and potential explanations for these puzzling data, and concludes with a discussion regarding the current state of weight reduction in the prevention and treatment of CV diseases.

Obesity has reached epidemic proportions in the United States and worldwide. Considering the adverse effects of obesity on left ventricular (LV) structure, diastolic and systolic function, and other risk factors for heart failure (HF), including hypertension and coronary heart disease, HF incidence and prevalence, not surprisingly, is markedly increased in obese patients. Nevertheless, as with most other cardiovascular diseases, numerous studies have documented an obesity paradox, in which overweight and obese patients, defined by body mass index, percent body fat, or central obesity, demonstrate a better prognosis compared with lean or underweight HF patients. This review will describe the data on obesity in the context of cardiopulmonary exercise testing in HF. Additionally, the implications of obesity on LV assist devices and heart transplantation are reviewed. Finally, despite the obesity paradox, we address the current state of weight reduction in HF.

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Omega-3 polyunsaturated fatty acid (omega-3 PUFA) therapy continues to show great promise in primary and, particularly in secondary prevention of cardiovascular (CV) diseases. The most compelling evidence for CV benefits of omega-3 PUFA comes from 4 controlled trials of nearly 40,000 participants randomized to receive eicosapentaenoic acid (EPA) with or without docosahexaenoic acid (DHA) in studies of patients in primary prevention, after myocardial infarction, and most recently, with heart failure (HF). We discuss the evidence from retrospective epidemiologic studies and from large randomized controlled trials showing the benefits of omega-3 PUFA, specifically EPA and DHA, in primary and secondary CV prevention and provide insight into potential mechanisms of these observed benefits. The target EPA + DHA consumption should be at least 500 mg/day for individuals without underlying overt CV disease and at least 800 to 1,000 mg/day for individuals with known coronary heart disease and HF. Further studies are needed to determine optimal dosing and the relative ratio of DHA and EPA omega-3 PUFA that provides maximal cardioprotection in those at risk of CV disease as well in the treatment of atherosclerotic, arrhythmic, and primary myocardial disorders.