Diagnostic dilemma: A joyful wedding nearly broke a woman's heart in a rare case of 'happy heart syndrome'

The patient: A 65-year-old woman in Qatar

The symptoms: The woman had been dealing with unexplained chest pain for several months, although earlier tests of her heart health had come back normal. She had stopped attending follow-up appointments regarding the chest pain.

But then, she experienced three days of chest pain and shortness of breath that got worse with activity. The symptoms, which began shortly after she attended her daughter’s wedding, initially brought her to a clinic, according to a report of the case.

An electrocardiogram (ECG or EKG) showed changes in her heart's electrical activity. This is a sign doctors look for when diagnosing a heart attack, because during the event, blood flow to the heart is impaired and that can injure or kill heart-muscle cells. So, the patient was rushed to a hospital emergency department.

What happened next: By the time the patient reached the emergency room, her chest pain had eased, but a repeat ECG showed different electrical abnormalities from the local clinic.

Blood tests showed an elevated level of troponin, a protein that leaks into blood when heart muscle is damaged. An ultrasound of her heart showed that its main pumping chamber, the left ventricle, wasn't squeezing properly; its pumping strength, known as ejection fraction, had dropped from 58% five months earlier to just 35%. (The healthy range is 50% to 70%.) The left ventricle had also ballooned out of shape at the tip.

Doctors performed an angiogram, a test that uses a thin tube and dye to check for blocked arteries, and found that her arteries were clear.

An X-ray of her heart confirmed the same ballooning shape that was seen on the ultrasound, and an MRI ruled out permanent damage from a silent heart attack or scarring of the tissue.

The diagnosis: Doctors diagnosed the patient with takotsubo cardiomyopathy, also known as stress cardiomyopathy or "broken heart syndrome." The condition temporarily weakens the heart muscle and causes it to balloon, producing symptoms that closely resemble a heart attack.

The condition is thought to be triggered by a sudden surge of stress hormones, such as adrenaline (also called epinephrine), that temporarily stun the heart. The diagnosis was confirmed using the Mayo Clinic's diagnostic criteria, which require ruling out other potential causes, such as heart inflammation (myocarditis), and confirming that there are no significant artery blockages.

The criteria also require that the affected part of the heart extend beyond the area supplied by just one artery — different from a typical heart attack, which usually damages only the region fed by a single blocked vessel. Doctors also look for new ECG changes with modest troponin elevation.

The treatment: The woman was treated with standard medications for heart failure medical therapy, such as beta blockers, and discharged once she was stable, with a follow-up scheduled at a heart-failure clinic. She resumed her usual daily activities without limitations, and a follow-up ECG showed that her heart's pumping function had recovered to 56%, close to her original baseline.

What makes the case unique: According to the report, takotsubo cardiomyopathy is most often triggered by distressing events, such as the death of a loved one or a serious diagnosis. In this case, though, the trigger was a happy one, which made it an example of "happy heart syndrome," a rare subtype of the condition first described by researchers in 2016. Intense positive emotions can activate some of the same stress pathways in the body that negative ones do, as these cases demonstrate.

Takotsubo cardiomyopathy accounts for an estimated 1% to 3% of cases of acute coronary syndromes, an umbrella term for conditions that involve sudden reduced blood flow to the heart. Within that group, the happy heart variant is rarer still. An analysis of the International Takotsubo Registry, which has data from more than 1,700 broken-heart patients around the world, found that positive emotional triggers were behind about 4.1% of emotionally triggered cases. The large majority were tied to grief, fear or other distressing events.

Compared with the classic symptoms of broken heart syndrome, happy heart syndrome tends to produce a different pattern of heart muscle ballooning that more often affects the middle or base of the heart in addition to the tip. That alternate pattern was not seen in this case, though.

Some research suggests happy heart patients may have milder symptoms and better outcomes than broken heart patients; they have a lower chance of severe heart failure during their hospital stay, for instance. That said, the authors noted that further data is needed to confirm this difference.

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