Diabesity: the combined burden of obesity and diabetes on heart disease and the role of imaging

In this Review, Bax and colleagues summarize the effects of obesity and diabetes on myocardial structure and function and evaluate the role of multimodality cardiac imaging to elucidate the pathophysiology of myocardial dysfunction, prognosticate long-term clinical outcomes and potentially guide treatment strategies.Diabesity is a term used to describe the combined adverse health effects of obesity and diabetes mellitus. The worldwide dual epidemic of obesity and type 2 diabetes is an important public health issue. Projections estimate a sixfold increase in the number of adults with obesity in 40 years and an increase in the number of individuals with diabetes to 642 million by 2040. Increased adiposity is the strongest risk factor for developing diabetes. Early detection of the effects of diabesity on the cardiovascular system would enable the optimal implementation of effective therapies that prevent atherosclerosis progression, cardiac remodelling, and the resulting ischaemic heart disease and heart failure. Beyond conventional imaging techniques, such as echocardiography, CT and cardiac magnetic resonance, novel post-processing tools and techniques provide information on the biological processes that underlie metabolic heart disease. In this Review, we summarize the effects of obesity and diabetes on myocardial structure and function and illustrate the use of state-of-the-art multimodality cardiac imaging to elucidate the pathophysiology of myocardial dysfunction, prognosticate long-term clinical outcomes and potentially guide treatment strategies.Cardiolog

Altered Hemodynamics and End-Organ Damage in Heart Failure: Impact on the Lung and Kidney

Heart failure is characterized by pathologic hemodynamic derangements, including elevated cardiac filling pressures ("backward" failure), which may or may not coexist with reduced cardiac output ("forward" failure). Even when normal during unstressed conditions such as rest, hemodynamics classically become abnormal during stressors such as exercise in patients with heart failure. This has important upstream and downstream effects on multiple organ systems, particularly with respect to the lungs and kidneys. Hemodynamic abnormalities in heart failure are affected by processes that extend well beyond the cardiac myocyte, including important roles for pericardial constraint, ventricular interaction, and altered venous capacity. Hemodynamic perturbations have widespread effects across multiple heart failure phenotypes, ranging from reduced to preserved ejection fraction, acute to chronic disease, and cardiogenic shock to preserved perfusion states. In the lung, hemodynamic derangements lead to the development of abnormalities in ventilatory control and efficiency, pulmonary congestion, capillary stress failure, and eventually pulmonary vascular disease. In the kidney, hemodynamic perturbations lead to sodium and water retention and worsening renal function. Improved understanding of the mechanisms by which altered hemodynamics in heart failure affect the lungs and kidneys is needed in order to design novel strategies to improve clinical outcomes

Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction. A Community-Based Study

Journal of the American College of Cardiology53131119-112

Age-associated increases in pulmonary artery systolic pressure in the general population

Circulation119202663-267

A Fluid Challenge Test for the Diagnosis of Occult Heart Failure

A right heart catheterization with measurements of pulmonary artery wedge pressure (PAWP) may be necessary for the diagnosis of left heart failure as a cause of pulmonary hypertension or unexplained dyspnea. Diagnostic cutoff values are a PAWP of ≥ 15 mm Hg at rest or a PAWP of ≥ 25 mm Hg during exercise. However, accurate measurement of PAWP can be challenging and heart failure may be occult. Left heart catheterization, with measurement of left ventricular end-diastolic pressure, may also be indecisive. Measurements are then best repeated in stress conditions. Exercise is an option, but the equipment is not universally available, and interpretation can be difficult in patients with wide respiratory pressure swings. An alternative is offered by a fluid challenge. Studies have gathered data supporting infusion of 500 mL or 7 mL/kg saline and a PAWP of 18 mm Hg as a diagnostic cutoff. The procedure is simple and does not take much catheterization laboratory time. Combining echocardiography with invasive measurements may increase the diagnostic accuracy of diastolic dysfunction. Cardiac output after a fluid challenge may be of prognostic relevance.SCOPUS: re.jDecretOANoAutActifinfo:eu-repo/semantics/publishe

Cardiac structure and ventricular-vascular function in persons with heart failure and preserved ejection fraction from Olmsted County, Minnesota

Circulation115151982-199

Impact of body mass index and diabetes on myocardial fat content, interstitial fibrosis and function

Purpose We hypothesize that both increased myocardial steatosis and interstitial fibrosis contributes to subclinical myocardial dysfunction in patients with increased body mass index and diabetes mellitus. Background Increased body weight and diabetes mellitus are both individually associated with a higher incidence of heart failure with preserved ejection fraction. However, it is unclear how increased myocardial steatosis and interstitial fibrosis interact to influence myocardial composition and function. Methods A total of 100 subjects (27 healthy lean volunteers, 21 healthy but overweight volunteers, and 52 asymptomatic overweight patients with diabetes) were prospectively recruited to measure left ventricular (LV) myocardial steatosis (LV-myoFat) and interstitial fibrosis (by extracellular volume [ECV]) using magnetic resonance imaging, and then used to determine their combined impact on LV global longitudinal strain (GLS) analysis by 2-dimensional (2D) speckle tracking echocardiography on the same day. Results On multivariable analysis, both increased body mass index and diabetes were independently associated with increased LV-myoFat. In turn, increased LV-myoFat was independently associated with increased LV ECV. Both increased LV-myoFat and LV ECV were independently associated with impaired 2D LV GLS. Conclusion Patients with increased body weight and patients with diabetes display excessive myocardial steatosis, which is related to a greater burden of myocardial interstitial fibrosis. LV myocardial contractile function was determined by both the extent of myocardial steatosis and interstitial fibrosis, and was independent of increasing age. Further study is warranted to determine how weight loss and improved diabetes management can improve myocardial composition and function