Clot-dissolving therapy stops ‘submassive PE’

INGELHEIM, Germany – Clinical trial results published last week in the New England Journal of Medicine demonstrated that the clot-dissolving agent alteplase (Actilyse tPA) can prevent the clinical deterioration of patients with submassive pulmonary embolism.

These patients still have normal blood pressure and no cardiogenic shock, but whose right ventricle or chamber of the heart, is functioning poorly due to increased pressure caused by blood clots traveling from other areas of the body to the lung vessels. If not halted, submassive pulmonary embolism (PE) can progress to massive PE, a life-threatening condition.

"Alteplase has long been used to treat pulmonary embolism patients experiencing a complete circulatory collapse and who are in immediate danger of dying (massive PE)," said Prof. Stavros Konstantinides, the study’s lead investigator.

"Only now have we learned that alteplase is also effective for patients with a submassive form of PE," he said. "Such patients have compromised heart function, but have not yet progressed to cardiogenic shock."

"Based on these findings, many more patients should be treated at this stage in their disease, thus, saving more lives," he said.

Konstantinides is an associate professor of medicine at the Department of Cardiology of Georg August University in Goettingen, Germany.

This prospective, randomized, double-blind and placebo-controlled study, the largest-ever trial of thrombolysis in pulmonary embolism, enrolled 256 patients.

More than 70 percent of the 256 patients had a history of deep vein thrombosis, a condition in which blood clots form in the deep veins of the arms or legs. Such clots form when blood flow is stagnant, as might occur in a bedridden patient, or when an otherwise healthy person is immobile for a long period of time in a confined space, such as on an airplane seat or the so-called "coach-class syndrome."

Sudden or strenuous activity after the clot has formed while, for example, quickly standing up and carrying heavy luggage off the plane, can dislodge the clot into the main blood circulatory system. The clot is eventually deposited in the pulmonary artery, where it places a strain on the heart.

Said Konstantinides: "For many years we debated the relative risks and benefits of thrombolysis in stable pulmonary embolism patients. Now we can clearly see that thrombolytic therapy is a safe method for preventing the progression of disease."

Actilyse is marketed worldwide by Boehringer Ingelheim, except in the United States and Canada. – PLG News & Views