The existence of Diabetic Cardiomyopathy has long been debated since it was first introduced about 30 years ago. While almost every healthcare professional is aware of the increased morbidity and mortality rates of cardiac disease in diabetics, correlating cardiomyopathy as a result of hyperglycemia without taking into account current blood pressure and coronary artery disease has always given the medical community cause for pause. However, many fields of study point towards a reality where hyperglycemia is a major culprit of cardiac dysfunction as it relates to diabetes since chronically high levels of blood glucose cause physical damage to the microvasculature and coronary arteries. Due to the parallels in the rise of diabetes mellitus together with cardiomyopathy, it must be studied and researched further so as to clearly understand a diabetic induced cardiomyopathy.
Various cardiac deformities and abnormal cardiac functions have been recorded in animals with diabetes. In the 70s and 80s, a team of researchers induced diabetes in canines by using a drug called Alloxan. By examining the hemodynamics, biochemical and histological findings of cardiac muscles of these animals, the researchers found a decrease in the quantity of blood the ventricles expel per contraction even though ventricular and diastolic pressure never faltered. Hardening of cardiac chambers was observed in the diabetes-induced dogs versus the healthy control dogs and could not be avoided by insulin.
In rats, extended isovolumetric contractions and diastole occurred along with ventricular hypertrophy and the aforementioned chamber hardening. The following biochemical alterations were observed:
– ATPase and Isoenzymes
– Impairment of Calcium Ion Transport
– Alterations in Receptor functionality
– Alterations in the metabolism of lipids, carbs and adenine nucleotide translocator
The findings in animal research vigorously reinforce the corollary between cardiac myopathy and diabetes.
Coronary artery disease develops at an earlier age for many diabetes patients, this is well known. Small vessel disease is partly responsible for diabetic cardiomyopathy but ventricular hypertrophy and its contributions to it are largely underestimated. Because of the strong association between hypertension and diabetes, it follows that ventricular hypertrophy is a result of said hypertension.
Having said this, diabetic women seem to have a tendency towards larger ventricular sizes than diabetic men. As such, it is proposed that increased ventricular mass occurs in diabetic patients independently from high blood pressure, as shown by echocardiography. Common deformities affecting cardiac integrity in diabetic patients include:
– Microvascular narrowing
– Interstitial Fibrosis
If hypertension is added to the formula, cardiac problems are only compounded further and is a major red flag for predicting congestive heart failure.
Thanks to many experimental findings and data, diabetes is now accepted as a risk factor for the advancement of cardiac disease. Heart failure is doubly prevalent in men with diabetes than their healthy male counterparts. Diabetic women on the other hand suffer heart failure at 5 times a greater clip than non-diabetic females. This extreme hazard for congestive heart failure remains in spite of adjusting the data for age, weight and an underlying presence of hypertension, hypercholesterolemia and coronary heart disease. While diabetes and hypertension are independently deadly in and of themselves, there appears to be a synergy, or cooperation between the two that may ultimately lead to heart failure. It is believed that treating high blood pressure with ACE (Angiotensin Converting Enzyme Inhibitor) in diabetic patients will impede the progression of Diabetic Cardiomyopathy. However, the standardization of treatment with ACE is still in preparatory fazes as more data comes in and conclusive results emerge.