It turns out that heart disease with its arterial sclerosis and consequent hypertension is the result of long term inflammation. Both arteries and veins as well as the whole circulatory system can become inflamed due to malfunctioning immune cells. And the main trigger for their malfunctioning seems to be too much blood sugar.
When arteries become inflamed it causes a lipid plaque to form. The immune system's attempts to heal the damage with monocytes goes a bit awry. When that plaque ruptures and an arterial thrombosis occurs, heart attack or stroke is the result. The old way of looking at cardiovascular disease was to look at the plaque and what it was made of (cholesterol and other things) rather than looking at what made the plaque happen in the first place. Inflammation is the cause of the plaque and it has nothing to do with fat - saturated or otherwise.
So in summary, chronic sleep disturbance is a very particular, very strong form of long-term stress; long-term stress always causes inflammation across all organ systems and a suppressed immune response - particularly in the circulatory system. Inflammation in arteries and veins causes cardiovascular disease. Thus, chronic sleep disturbance can cause heart attack and stroke.
Surprising maybe, but very real.