Carrie O'Connor thought she was a fairly healthy 35-year-old who went on daily jogs and ate well.
Then, more than a year ago, she suffered back-to-back heart attacks.
The first hit while she was treating herself to baubles at Smyth Jewelers in Timonium, Md. The project manager at T. Rowe Price suddenly felt nauseated and severe pain consumed her stomach. Pain shot up her arm and her jaw ached. All were common symptoms of a heart attack, the paramedics later told her.
The second happened later that day when doctors tried to insert a stent to open a blocked left artery they believed had caused the first attack. During the procedure, two of her other arteries began to spasm and she had a massive heart attack.
Heart disease is often seen as an older person's affliction. Nationwide, the average age at a first heart attack is 64 for men and 72 for women, according to the American Heart Association. About 10 years ago, the average ages were 65.8 for men and 70.4 for women.
But heart attacks also can occur in younger patients like O'Connor who are seemingly healthy, caught off guard by the life-changing illness. They find themselves dealing with problems more typical of people their parents' age, taking loads of pills and limiting strenuous activity to protect their weakened hearts.
"It was not something I expected at all," O'Connor said. "We don't have family history. I don't have any typical risk factors. I'm not overweight. I don't smoke. I eat fine."
At Anne Arundel Medical Center, where O'Connor received cardiac rehabilitation, the hospital saw such a surge in young patients that it started a support group to help them cope. In 2009, the average age of heart attack patients at the hospital was 70 years. In 2012, it was 60.
"In addition to the bread-and-butter standard cases, we are seeing it in younger folks and it is not completely clear why that is," said Scott Katzen, a general and interventional cardiologist with Cardiology Associates who has privileges at Anne Arundel Medical Center.
In recent years, some high-profile deaths have brought further attention to the issue. James Gandolfini, who starred in the popular "The Sopranos" television series, died at age 51 from a massive heart attack. Actor Michael Clarke Duncan died at age 54 after suffering a heart attack.
Doctors believe some of the attacks are brought on by genetic causes, but doctors also point to the nation's obesity problem as a factor. Stress also could play a role, although further study needs to be done, some doctors said.
Doctors have started to pay better attention to possible symptoms in younger patients and not discount signs because of the person's age, said Jeffrey L. Quartner, chief of cardiology at MedStar Union Memorial Hospital and a board member of the American Heart Association Maryland.
"We have changed our sensitivity to realize young people have heart attacks as well," Quartner said.
Ana Pendleton Duhon, a 37-year-old teacher, was riding in the car with her mother in June 2012. That is the last thing she remembers from that day.
Her mother would later tell her she slumped over in mid-conversation. Paramedics shocked Duhon's heart three times to revive her. Doctors would determine later she went into cardiac arrest.
Duhon recovered, but doctors aren't 100 percent sure what caused the attack and the incident has changed her life forever. Her heart only operates at 30 percent of its function and she takes numerous medications. Doctors implanted a defibrillator on her heart so if she suffers another attack it will automatically shock the organ.
The biggest change has been the emotional effect. Once a personal trainer in tip-top health, Duhon now sometimes worries whe-ther her heart will fail again.
She and O'Connor were the first members of the support group started at Anne Arundel Medical Center to help young people cope after a heart attack.
"We needed a community to talk about this," Duhon said. "We're young women who didn't expect any of this to happen."
Dianne Walters, a nurse in the cardiac rehab unit at Anne Arundel Medical Center who helps run the support group, said younger patients may go into depression and start to question their mortality. Talking to people their age helps them accept their situation, she said.
John Weitzel, a 48-year-old Crownsville, Md., contractor, felt symptoms for almost two days before having a heart attack in 2013. He felt numbness in his arms and jaw, a tightness in his chest and felt as if he had bad indigestion. His body was achy all over. He visited an urgent-care center and was sent home.
Weitzel was walking to the bathroom when he fell in the hallway. His wife heard his body crash and called an ambulance.
Weitzel was overweight and didn't eat well before suffering his heart attack. He has since lost 30 pounds and is trying to live better.
He said the support group has helped.
"It was a wake-up call," he said. "It's hard to realize you're young and have some serious heart problems."