Heart failure is the inability

#Heart failure is the inability of the #heart to provide adequate #blood to the body and its organs at rest or during exercise, or at the expense of elevated filling pressure. Heart failure with preserved #ejection fraction or “heff-peff” is characterized by #stiff #ventricles with a preserved ejection fraction. This is usually caused by an #impairment in #diastolic function which is characterized by impaired relaxation of the left ventricle, and reduced left ventricular compliance, resulting in increased left ventricular diastolic pressures. The #ventricle is too stiff to allow normal filling during #diastole, and so pressures are high to get blood into the ventricle. Left #atrial enlargement is also often seen in #HFpEF. Several factors contribute to the #pathophysiology of this multi-factorial disease. #Hypertension is an example of a common cause of #HFpEF and drives arterial stiffness, as well as ventricular hypertrophy and fibrosis. Elevated blood pressure and stiff arteries result in increased #peripheral resistance in the #circulation and the heart must work harder to pump blood through these stiff vessels. This increased strain on the heart may result in hypertrophied ventricles which contribute to the #dysfunction we see in #HFpEF. Comorbidities like aging, #obesity, and #metabolic disease may drive #myocardial dysfunction and remodeling on a cellular level that contributes to #ventricular stiffness. These comorbidities are linked to an increase in #microvascular #endothelial #inflammation and the generation of reactive oxygen species, which ultimately contributes to #nitric oxide deficiency. In a normal heart, nitric oxide is available to initiate a pathway that causes muscle relaxation. Without nitric oxide available for this pathway, however, there is less #cyclic #GMP available to activate #Protein_Kinase_G, a protein involved with muscle relaxation. Relaxation is slower, which results in stiff #ventricles. All the causes described previously contribute to #diastolic #dysfunction and #diastolic dysfunction also contributes to those mechanisms.