Toni Braxton looked sexy and fluid Monday, dancing the cha-cha with her partner Alec Mazo on the season premiere of the reality dance competition "Dancing With the Stars," and the judges praised her lively quickstep on Tuesday.
But competing in the show's seventh season may be more of a challenge for the six-time Grammy winner than for her competitors.
Earlier this year, Braxton, 40, was diagnosed with microvascular angina, a disease where tiny blood vessels bringing blood to the heart become blocked.
Although cardiologists caution that the disease can lead to an increased risk of heart attack, microvascular angina is not so serious that a healthy, conscientious person cannot participate in rigorous activity like that of a dance competition.
"Generally, exercise is recommended by us cardiologists," said Dr. Christopher Cannon, a cardiologist and associate professor of medicine at Harvard Medical School. "Dancing is a good way to exercise. With angina, one has to gauge the amount of exercise and what level of exercise brings out any chest pain."
On the spectrum of cardiac diseases, microvascular angina is one of the less serious illnesses, doctors say, but it is among the more difficult to diagnose. This is because blockages occur in the tiny blood vessels around the heart rather than in the major arteries, making them hard to see.
"Generally, the prognosis is very good in that there aren't major problems seen with the heart," Cannon said. "It becomes more of a symptoms problem than one where you have to worry about death or heart attack."
Even if Braxton were to experience symptoms on the show, they may not be dramatic.
Cannon said this type of angina can feel like a bad stomachache, with some pressure and discomfort in the chest.
Some treatments, including nitroglycerine, calcium channel blockers and ACE inhibitors can help dilate blood vessels and increase blood flow to the heart.
In addition, lifestyle changes to help control levels of cholesterol, blood pressure and sugar, refraining from smoking and exercise will promote heart health.
"In general exercise is good for patients with stable microvascular angina because it leads to improved efficiency of the heart," said Dr. Maryann McLaughlin, assistant professor of cardiology and health policy at Mount Sinai School of Medicine in New York.
Microvascular angina can be easy to monitor. As soon as exertion brings on symptoms, McLaughlin said, check your heart rate. In the future, wearing a heart monitor to keep from exceeding that number can help prevent angina symptoms.
"If you've been tested and you watch for symptoms, you can exercise safely," McLaughlin said.
While the physical exertion may not be problematic, and may even be beneficial, for Braxton, the mental strain of competition has the potential to do vascular harm.
"The stress part is where it would be a little bit of a detriment," Cannon said.
Stress has the opposite effect on arteries that exercise does. Instead of dilating, arteries contract, becoming smaller and reducing blood flow to the heart.
But Braxton, a seasoned performer who is used to being on stage, may be better able than others with microvascular angina to handle the rush of a live performance.
"She might not have the same acceleration of adrenaline," McLaughlin said, noting that adrenaline can increase heart rate, a risk for angina symptoms. "She will be more conditioned to it."
Although cardiac problems in women typically occur in the 10 years after menopause, they can occur in younger women as well. Studies done in the last two years suggest that microvascular angina, while not very common, occurs more frequently in women than in men and can increase the risk of heart attack.
McLaughlin also pointed out that the condition, which may have been underdiagnosed in the past, is more apparent because of modern diagnostic techniques such as PET scans.
"[Women] should take chest pain seriously and get an evaluation from a physician," McLaughlin said.
In the face of her diagnosis, Braxton seems resolved to persist in the competition.
"My goal in this competition is very personal," Braxton said Tuesday night in an interview on "Dancing With the Stars," which is broadcast by ABC. "I want to prove that I have the heart to go out there on a dance floor and just do my thing."