George W. Bush's recent heart problems were far more dangerous than generally believed -- potentially life-threatening, in fact.
Sources familiar with the former president's medical situation told National Journal that a major blockage in a coronary artery discovered during Bush's annual physical exam in August had almost completely shut off blood flow to one of his heart chambers.
"He was more than 95% occluded," an authoritative source said. "With a blockage like that in a main artery you're supposed to die. He was pretty lucky they caught it."
Dr. Jonathan Reiner, an interventional cardiologist at George Washington University who has treated former Vice President Dick Cheney but was not involved in Bush's care, noted that a blockage of that magnitude wouldn't necessarily be fatal in all patients but is a very serious situation requiring prompt treatment.
"Every case is different," Reinert said. "It depends on several factors, including how quickly a blockage has developed. But it's a very important vessel. If you occlude that particular artery it can kill you."
A prominent internist who asked not to be identified added that Bush's blockage, if undiagnosed, would almost certainly have risked "a grave cardiac event."
Even with a 95 percent blockage, Reiner said, blood will still be flowing through the impaired artery, but the heart muscle must work harder, particularly during vigorous activity. The added strain when blood flow is diminished can lead to serious cardiac complications, including a heart attack.
The 43rd president has exercised regularly for years and is generally believed to be in excellent health. Nevertheless, a stress test that's standard with all physicals at the renowned Cooper Clinic in Dallas turned up worrisome changes to Bush's electrocardiogram readings. His physicians quickly ordered up a CT angiogram that revealed the magnitude of the blockage and prompted them to recommend inserting a stent to open the artery. That procedure was done the next morning at Texas Health Presbyterian Hospital without complication. Bush spent the night at the hospital for observation and is reported to be recovering normally.
At the time some physicians wondered whether the stent was medical overkill, given that Bush has no known family history of heart disease and is in good shape. Multiple sources knowledgeable about Bush's condition, however, said there's no question the treatment was medically necessary.
A spokesman for the Cooper Clinic declined to discuss any aspects of Bush's care, citing patient privacy. Bush spokesman Freddy Ford also declined comment.
By all appearances, the ex-president has bounced back smartly from his health scare. He's been cleared to travel, attending the President's Cup golf matches in Ohio last weekend. He's also returned to playing golf and riding mountain bikes, but doctors have put limits on his normally-manic speeds and the duration of his workouts.
"He's back on the bike -- easy, not hard," a friend said. "But he's feeling terrific and doing fine."