Vertebrates developed pulmonary circulation and septated the heart into venous and arterial compartments, as the adaptation from aquatic to terrestrial life requires more oxygen and energy. The interventricular septum (IVS) accommodates the ventricular portion of the conduction system and contributes to the mechanical function of both ventricles. Conditions or diseases that affect IVS structure and function (e.g., hypertrophy, defects, other) may lead to ventricular pump failure and/or ventricular arrhythmias with grave consequences. IVS structure and function can be evaluated today using current imaging techniques. Effective therapies can be provided in most cases, although definitions of underlying etiologies may not always be easy, particularly in the elderly due to overlap between genetic and acquired causes of IVS hypertrophy, the most common being IVS abnormality. In this review, state-of-the-art information regarding IVS morphology, physiology, physiopathology, and disease is presented.
Objective: To study the long term cardiovascular effects of oral antidiabetic agents in non-diabetic patients with insulin resistance. Patients: 181 African American subjects with insulin resistance and normal glucose tolerance test were randomised to receive glipizide 5 mg/day (n = 25), metformin 500 mg/day (n = 59), or placebo (n = 97) for 24 months. Insulin sensitivity, glucose tolerance, lipid profile, left ventricular mass (echocardiography), aortic distensibility (echocardiography, blood pressure), aortic pulse wave velocity (PWV, carotid to femoral artery, Doppler) were measured at baseline and at 12 and 24 months after randomisation. Results: A significant increase in PWV was observed in both glipizide (mean (SEM) change at 24 months 2.8 (2.7) m/s, p = 0.012) and metformin (2.2 (0.7) m/s, p = 0.01) groups during the follow up period. In contrast, PWV remained unchanged in the placebo group. The increase in PWV in the treatment groups was significant compared with placebo (analysis of variance p < 0.05). Other cardiovascular or metabolic variables did not change significantly compared with placebo during follow up. Conclusions: The observed increase in PWV is consistent with a decrease in the elastic properties of the aorta. The use of oral antidiabetic agents for the prevention of cardiovascular complications in non-diabetic African Americans with insulin resistance needs to be critically evaluated.
Multimorbidity, the coexistence of multiple health conditions in an individual, has emerged as one of the greatest challenges facing health services, and this crisis is partly driven by the aging population. Aging is associated with increased aortic stiffness (AoStiff), which in turn is linked with several morbidities frequently affecting and having disastrous consequences for the elderly. These include hypertension, ischemic heart disease, heart failure, atrial fibrillation, chronic kidney disease, anemia, ischemic stroke, and dementia. Two or more of these disorders (multimorbidity) often coexist in the same elderly patient and the specific multimorbidity pattern depends on several factors including sex, ethnicity, common morbidity routes, morbidity interactions, and genomics. Regular exercise, salt restriction, statins in patients at high atherosclerotic risk, and stringent blood pressure control are interventions that delay progression of AoStiff and most likely decrease multimorbidity in the elderly.
Accumulation of medical knowledge related to diagnosis and management over the last 5-6 decades has altered the course of diseases, improved clinical outcomes and increased survival. Thus, it has become difficult for the practicing physician to evaluate the long-term effects of a particular therapy on survival of an individual patient. Further, the approach by each physician to an individual patient with the same disease is not always uniform. In an attempt to assist physicians in applying newly acquired knowledge to patients, clinical practice guidelines were introduced by various scientific societies. Guidelines assist in facilitating the translation of new research discoveries into clinical practice; however, despite the improvements over the years, there are still several issues related to guidelines that often appear ‘lost in translation'. Guidelines are based on the results of randomized clinical trials, other nonrandomized studies, and expert opinion (i.e. the opinion of most members of the guideline committees). The merits and limitations of randomized clinical trials, guideline committees, and presentation of guidelines will be discussed. In addition, proposals to improve guidelines will be presented.
Angiotensin (ANG)-converting enzyme (ACE2) is an entry receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19). ACE2 also contributes to a deviation of the lung renin–angiotensin system (RAS) towards its counter-regulatory axis, thus transforming harmful ANG II to protective ANG (1–7). Based on this purported ACE2 double function, it has been put forward that the benefit from ACE2 upregulation with renin–angiotensin–aldosterone system inhibitors (RAASi) counterbalances COVID-19 risks due to counter-regulatory RAS axis amplification. In this manuscript we discuss the relationship between ACE2 expression and function in the lungs and other organs and COVID-19 severity. Recent data suggested that the involvement of ACE2 in the lung counter-regulatory RAS axis is limited. In this setting, an augmentation of ACE2 expression and/or a dissociation of ACE2 from the ANG (1–7)/Mas pathways that leaves unopposed the ACE2 function, the SARS-CoV-2 entry receptor, predisposes to more severe disease and it appears to often occur in the relevant risk factors. Further, the effect of RAASi on ACE2 expression and on COVID-19 severity and the overall clinical implications are discussed.