Loss of functional heart muscle has its roots in many etiologies. ischemic vs non-ischemic cardiomyopathy. Uncontrolled diabetics succum to CAD (coronary artery disease) via the atherosclerotic process much in the same way as non diabetics. Diabetes is just other risk factor when stratifing patients for risk (propensity) to develope CAD. Acute Coronary Syndrome (MI, unstable angina, stable angina) is an ischemic process, meaning the oxygen supply to the myocardium is insuffcient to meet the metabolic demands of the body. Diabetics also lose the capacity to effectively generate collateral circulation which is the body's defense ( or defence) against the narrowing of the medium sized arteries surrounding the heart which are the main culprits when we describe CAD. So it is probably correct to say the people that die from sudden cardiac death and are diabetics died from a heart attact but the disease process was complicated by diabetes. Hope this helps

Pup