CORPUS CHRISTI, Texas – The 78-year-old lawyer wounded by Vice President Cheney in a hunting accident suffered a mild heart attack yesterday after a shotgun pellet in his chest traveled to his heart, hospital officials said.

Harry Whittington was immediately moved back to the intensive care unit and will be watched for a week to make sure more of the metal pellets do not reach other vital organs. He was reported in stable condition.

Mr. Whittington suffered a “silent heart attack” – obstructed blood flow, but without the classic heart-attack symptoms of pain and pressure, according to doctors at Christus Spohn Hospital Corpus Christi-Memorial.

The doctors said they decided to treat the situation conservatively and leave the pellet alone rather than operate to remove it. They said they are highly optimistic Mr. Whittington will recover and live a healthy life with the pellet in him.

Asked whether the pellet could move farther into his heart and become fatal, hospital officials said that was a hypothetical question they could not answer.

Hospital officials said they were not concerned about the six to 200 other pieces of birdshot that might still be lodged in Mr. Whittington’s body. Mr. Cheney was using 7 1/2 shot from a 28-gauge shotgun. Shotgun pellets are typically made of steel or lead; the pellets in 7 1/2 shot are just under a tenth of an inch in diameter.

Mr. Cheney watched the news conference where doctors described Mr. Whittington’s complications. Then the vice president called him, wished him well, and asked if there was anything that he needed.

“The vice president said that he stood ready to assist. Mr. Whittington’s spirits were good, but obviously his situation deserves the careful monitoring that his doctors are providing,” the vice president’s office said in a statement.

Mr. Cheney, an experienced hunter, has not spoken publicly about the accident, which took place Saturday night while the vice president was aiming for a quail. Critics of the Bush administration called for more answers from Mr. Cheney himself.

Mr. Whittington has said through hospital officials that he does not want to comment on the shooting. A young man at Mr. Whittington’s Austin home who identified himself as his grandson said yesterday he did not have time to talk to a reporter and closed the door.

The furor over the accident and the White House delay in making it public are “part of the secretive nature of this administration,” said Senate Democratic Leader Harry Reid of Nevada. “I think it’s time the American people heard from the vice president.”

Before hospital officials announced details of Mr. Whittington’s condition, the hunting accident had produced a raft of Cheney jokes on late-night television.

“I think Cheney is starting to lose it,” Jay Leno said. “After he shot the guy he screamed, ‘Anyone else want to call domestic wiretapping illegal?!'”

Yesterday morning, the White House spokesman briefly joined in the merriment, joking that the orange school colors of the visiting University of Texas championship football team should not be mistaken for hunters’ safety gear.

“The orange that they’re wearing is not because they’re concerned that the vice president may be there,” press secretary Scott McClellan said. “That’s why I’m wearing it.”

Hospital officials said they knew that Mr. Whittington had some birdshot near his heart and that there was a chance it could move closer since scar tissue had not had time to harden and hold the pellet in place.

After Mr. Whittington developed an irregular heartbeat, doctors performed a cardiac catheterization, in which a thin, flexible tube is inserted into the heart, to diagnose his condition, the administrator at the hospital, Peter Banko, said.

The shot was either touching or embedded in the heart muscle near the top chambers, called the atria, officials said. Two things resulted:

– It caused inflammation that pushed on the heart in a way to temporarily block blood flow, what the doctors called a “silent heart attack.” This is not a traditional heart attack where an artery is blocked. They said Mr. Whittington’s arteries, in fact, were healthy.

– It irritated the atria, caused an irregular heartbeat known as a trial fibrillation, which is not immediately life threatening. But it must be treated because it can spur blood clots to form. Most cases can be corrected with medication.

White House physicians helped advise on the course of treatment, hospital officials said.

Texas officials said the shooting was an accident and no charges were brought against the vice president.

A Texas Parks and Wildlife Department report issued Monday said Mr. Whittington was retrieving a downed bird and stepped out of the hunting line he was sharing with Mr. Cheney. “Another covey was flushed and Cheney swung on a bird and fired, striking Mr. Whittington in the face, neck and chest at approximately 30 yards,” the report said.