Collagen Deficit May Have Caused Rupture of Coronary Artery in Alport Patient, Researchers Say

In rare cases, Alport syndrome might affect the heart, as suggested by a case report of a woman who experienced a spontaneous coronary artery dissection (SCAD).

The condition, which is also rare in other patient groups, had never been described in Alport before. But researchers at the University of South Dakota Sanford School of Medicine caution fellow physicians to look out for the complication if encountering an Alport patient with chest pain.

The study, “Spontaneous Coronary Artery Dissection: A Rare Manifestation of Alport Syndrome,” appeared in the journal Case Reports in Cardiology.

The patient in question — an obese 36-year-old woman with X-linked Alport caused by a very rare mutation — had both chronic kidney disease and hypertension when she sought care at the emergency department for acute chest and neck pain.

Her pain radiated into both arms, which were numb. Laboratory tests indicated heart damage, so physicians treated her with aspirin and heparin before performing a coronary angiography. The procedure revealed a rupture in one of her coronary arteries, which provides blood to the heart. This condition, known as SCAD, can obstruct blood flow to the heart. It is potentially fatal if not treated promptly.

Examinations showed that the rupture in the inner part of the vessel had compressed the lumen of the artery, narrowing it by 40 percent.

Physicians performed a percutaneous balloon angioplasty, in which doctors insert a tiny balloon and inflate it to widen the blood vessel. To keep the vessel open, they placed a drug-eluting stent in the artery. A stent is a small wire mesh tube that is coated with medication to help the artery remain open.

The procedure allowed the woman to improve, but she continued taking drugs targeting blood vessel and heart functions. When she complained about shortness of breath six months later, doctors concluded it was not linked to the heart complication, as she did not lack oxygen in the heart.

While earlier reports have linked Alport syndrome to aortic complications, none of these complications have led to SCAD, like it did in this case.

Researchers suggested that the lack of functional collagen type 4, seen in Alport, might predispose patients to aortic ruptures, particularly if they have uncontrolled hypertension. Because of the difficulty in obtaining tissue samples from human coronary arteries, they admit that their theory remains speculative.

Animal studies might shed some light on the possible link between Alport syndrome and aortic rupture, they said, concluding that this case “illustrates that SCAD may be a manifestation of AS patients with chest pain.”