I think both the media and people in general confuse the terms "heart attack," "heart failure" and "cardiac arrest," aka "sudden cardiac death."
Typically the word "heart attack" refers to myocardial infarction, usually related to coronary artery disease. This is when plaque obstructs a large artery feeding the heart, causing a section of the heart muscle to die. It's usually something which occurs over a long period of time, though it may appear to happen suddenly. Sometimes a large blood clot could obstruct a coronary artery, causing an MI or "heart attack." I don't know if this commonly occurs with ebola, or even ever.
"Heart failure" typically occurs with age, certain illnesses, etc. The heart loses its pumping ability and finally stops beating. There are usually pretty good warning signs that this is occurring-person isn't healthy one minute, and dead the next.
"Cardiac arrest" can occur suddenly in apparently healthy individuals who have ingested certain drugs, have a congenital disorder which causes a fatal arrhythmia, or it can occur as a result of some serious electrolyte imbalances.
It seems to me that someone with ebola is most likely at risk for cardiac arrest due to the electrolyte imbalances which are largely the result of dehydration (think copius diarrhea and vomiting with ebola), or perhaps at the end, when the hemorrhagic phase manifests, or organ damage occurs at end stage.
It seems HIGHLY unlikely that anyone is walking around with ebola, and having no symptoms other than a sudden nose bleed and sudden cardiac death. They would have been extremely ill prior to those things occurring; the hemorrhagic nature of ebola (which doesn't always happen) is one of the very last manifestations of the disease, IIRC.
If the people referenced have actually had "heart attacks," ebola seems to me to be a next to impossible etiology, given the descriptions noted in those articles. Also, in the article about the woman with a "heart attack" who was bleeding from the "face, nose, and mouth," it states that she was found on the floor in that condition. It never quotes anyone who witnessed the event saying that she was bleeding first, then dropped dead. If she literally dropped dead from cardiac arrest, it seems possible that the bleeding could have been from the fall.
Costa, a man who works in the building next door, said: 'We were in the building and all the sudden the other owner came from the store and he said somebody dropped dead in their store.'
He then said he ran in there to find a woman laying on the floor.
When asked what she was bleeding from, Costa said: 'Face, nose, mouth, everything.'
That's not real convincing of a bleeding event which could have been associated with ebola. And apparently she tested negative for ebola, so I guess the point is moot in her case.
JMO.
So assumption CAN be made :moo: that heart issues (due to imbalance/low electrolytes) and bleeding (low platelet levels...nope.... EXTREMELY low platelet levels) are a result of HIGH viral loads. :moo: someone isn't going to die in that phase without having detectable virus. :moo: