Alpha-lipoic Acid:Effects on the Beat-to-Beat Vectorcardiographic Parameters in Type 2 Diabetes Mellitus Patients with Cardiac Autonomic Neuropathy

Objective:Relevance of cardiac autonomic neuropathy has not been fully recognized and there is no standardized treatment protocol.Aim:To evaluate the effects of alpha-lipoic acid on the beat-to-beat vectorcardiographic parameters,namely spatial QRS-T angle,QT dispersion(QTd)and corrected QT interval(QTc)in type 2 diabetes mellitus persons with cardiac autonomic neuropathy.Research designs and methods:Our study involved 33 persons with definite stage of cardiac autonomic neuropathy and diabetes mellitus type 2,which were assigned to each of two groups:one took standard antihyperglycaemic treatment(n=15,control group)and the other(n=18)in addition to standard therapy-600 mg of alpha-lipoic acid daily for three months.The analysis of vectorcardiographic parameters was performed.Results:It was found out that alpha-lipoic acid contributed to decrease of the vectorcardiographic parameters,namely QRS-T angle,QTd and QTc.Conclusions:The positive influences of alpha-lipoic acid suggest the usefulness of its prescription to type 2 diabetes mellitus persons with definite stage of cardiac autonomic neuropathy.The efficacy of alpha-lipoic acid is the result of its direct effect on the parameters of vectorcardiography.

Cardiovascular autonomic neuropathy in diabetes:Pathophysiology,clinical assessment and implications

Cardiovascular autonomic neuropathy(CAN)is a debilitating condition that mainly occurs in long-standing type 2 diabetes patients but can manifest earlier,even before diabetes is diagnosed.CAN is a microvascular complication that results from lesions of the sympathetic and parasympathetic nerve fibers,which innervate the heart and blood vessels and promote alterations in cardiovascular autonomic control.The entire mechanism is still not elucidated,but several aspects of the pathophysiology of CAN have already been described,such as the production of advanced glycation end products,reactive oxygen species,nuclear factor kappa B,and pro-inflammatory cytokines.This microvascular complication is an important risk factor for silent myocardial ischemia,chronic kidney disease,myocardial dysfunction,major cardiovascular events,cardiac arrhythmias,and sudden death.It has also been suggested that,compared to other traditional cardiovascular risk factors,CAN progression may have a greater impact on cardiovascular disease development.However,CAN might be subclinical for several years,and a late diagnosis increases the mortality risk.The duration of the transition period from the subclinical to clinical stage remains unknown,but the progression of CAN is associated with a poor prognosis.Several tests can be used for CAN diagnosis,such as heart rate variability(HRV),cardiovascular autonomic reflex tests,and myocardial scintigraphy.Currently,it has already been described that CAN could be detected even during the subclinical stage through a reduction in HRV,which is a non-invasive test with a lower operating cost.Therefore,considering that diabetes mellitus is a global epidemic and that diabetic neuropathy is the most common chronic complication of diabetes,the early identification and treatment of CAN could be a key point to mitigate the morbidity and mortality associated with this long-lasting condition.

Diabetic heart disease:A clinical update

Diabetes mellitus(DM) significantly increases the risk of heart disease,and DMrelated healthcare expenditure is predominantly for the management of cardiovascular complications.Diabetic heart disease is a conglomeration of coronary artery disease(CAD),cardiac autonomic neuropathy(CAN),and diabetic cardiomyopathy(DCM).The Framingham study clearly showed a 2 to 4-fold excess risk of CAD in patients with DM.Pathogenic mechanisms,clinical presentation,and management options for DM-associated CAD are somewhat different from CAD among nondiabetics.Higher prevalence at a lower age and more aggressive disease in DM-associated CAD make diabetic individuals more vulnerable to premature death.Although common among diabetic individuals,CAN and DCM are often under-recognised and undiagnosed cardiac complications.Structural and functional alterations in the myocardial innervation related to uncontrolled diabetes result in damage to cardiac autonomic nerves,causing CAN.Similarly,damage to the cardiomyocytes from complex pathophysiological processes of uncontrolled DM results in DCM,a form of cardiomyopathy diagnosed in the absence of other causes for structural heart disease.Though optimal management of DM from early stages of the disease can reduce the risk of diabetic heart disease,it is often impractical in the real world due to many reasons.Therefore,it is imperative for every clinician involved in diabetes care to have a good understanding of the pathophysiology,clinical picture,diagnostic methods,and management of diabetes-related cardiac illness,to reduce morbidity and mortality among patients.This clinical review is to empower the global scientific fraternity with up-to-date knowledge on diabetic heart disease.