Coronary microvascular dysfunction in diabetes mellitus:A review

The exploration of coronary microcirculatory dysfunction in diabetes has accelerated in recent years.Cardiac function is compromised in diabetes.Diabetic patients manifest accelerated atherosclerosis in coronary arteries.These data are confirmed in diabetic animal mod-els,where lesions of small coronary arteries have been described.These concepts are epitomized in the classic microvascular complications of diabetes,i.e.blindness,kidney failure and distal dry gangrene.Most importantly,accumulating data indicate that insights gained from the link between inflammation and diabetes can yield predictive and prognostic information of considerable clinical utility.This review summarizes the evidence for the predisposing factors and the mechanisms involved in diabetes,and assesses the current state of knowledge regarding the triggers for inflammation in this disease.We evaluate the roles of hyperglycemia,oxidative stress,polyol pathway,protein kinase C,advanced glycation end products,insulin resistance,peroxisome proliferator-activated receptor-γ,inflammation,and diabetic cardiomyopathy as a "stem cell disease".Furthermore,we discuss the mechanisms responsible for impaired coronary arteriole function.Finally,we consider how new insights in diabetes may provide innovative therapeutic strategies.

Ventricular Septal Crypts:Remnants of Spontaneous Interventricular Defect Closure?

Background:Ventricular crypts are quite a common finding during cardiac imaging,but their etiology is unclear.A possible final result of a spontaneous ventricular septal defect closure has been supposed but never investigated in earlier studies.Method:From January 1997 to December 2020,all newborns diagnosed to have a ventricular septal defect were prospectively entered in our database and those with an isolated defect were included in the study.Ventricular septal defects were classified into four types:perimembranous,trabecular muscular,inlet and outlet.A long-term follow up was performed in order to visualize the possible residual formation of a septal myocardial crypt.Results:A total of 376 isolated ventricular septal defects(314 muscular and 54 perimembranous,4 inlet,4 outlet)were detected.Follow up ranged from 1 to 23 years and showed that,among muscular type,a spontaneous closure occurred in 284(91%),26 did not close(8,28%),2 required surgical intervention(0,63%),3 were lost at follow up(0,95%).During this period,after spontaneous defect closure closure,20 crypts were found(6,4%).Conclusion:This study shows that a muscular ventricular septal defect may evolve in the 6.4%of cases in a residual septal crypt.Although septal crypts occur more frequently in patients affected by hypertrophic and hypertensive cardiomyopathy,they may also represent the evolution of a spontaneous closure of a muscular interventricular defect.