When the Los Angeles coroner recently released the cause of death for Jordan Feldstein, Philadelphia vascular medicine expert Geno Merli had one immediate thought: "Oh, no, not another one. Not another young person dying from a pulmonary embolism."

Feldstein, manager of the popular band Maroon 5 and brother of actor Jonah Hill, was 40 when he died in December. Physicians initially thought he was suffering from a heart attack. The autopsy revealed that he had blood clots in his legs – deep vein thrombosis, or DVT. One or more had apparently moved to his lungs, blocking an artery and causing his death.

The National Heart, Lung, and Blood Institute says estimates suggest 300,000 to 600,000 people nationwide are affected by DVT and pulmonary embolism every year. If left untreated, the institute says, 30 percent of people with a pulmonary embolism will die, most of them within a few hours of "the event" – the clot lodging in the lungs. But prompt diagnosis and proper treatment can change that dire outlook.

Merli, co-director of the Jefferson Vascular Center at Thomas Jefferson University Hospitals and a nationally recognized expert on DVT and PE, spoke to us recently about the condition.

When you first learned the cause of Feldstein’s death, what struck you? 

I always look at it from the standpoint of how young the person was. It's sad that a young person would die from a pulmonary embolism. I remember David Bloom, an NBC correspondent, who died in Iraq from one. He was 39, the father of three kids. It shocked everybody.

PEs are supposed to happen to older people. The older we get, the risk grows exponentially. That's because as you get older, you develop other comorbidities that increase your risk of developing blood clots.

Jordan Feldstein was obviously very young. One news report mentioned that he had pneumonia. Who knows how he came into the emergency room. Often, patients come into an emergency room, [they are] young, they may feel like they have pneumonia. They have a hard time breathing. They're not feeling well. Their heart rate is fast.

Emergency medicine physicians are trained to have the diagnosis of pulmonary embolism on their radar screens when patients present with shortness of breath. The four things physicians would think about first would be pneumonia, heart attack, lung cancer, and pulmonary embolism. They would follow a set pathway, or algorithm, to make the final diagnosis. In Feldstein's case the autopsy showed pneumonia, leg deep vein thrombosis, and pulmonary embolism. In addition, obesity, which increases your risk for clots, was noted as another significant finding.

What causes blood clots, and what is a common treatment? 

When it happens, you look for a provoking reason – age, obesity, infection, recent surgery, immobilization, medications like birth control pills, long air or car travel, and family history of blood clots. With these factors in mind, emergency-medicine physicians immediately initiate the evaluation to confirm the possible diagnosis. Once the pulmonary embolism is diagnosed, treatment with intravenous heparin, or injections of low-molecular weight heparin, both blood thinners, is started to treat the clot. In some severe circumstances, clot-busting medicine may be used. Then, on a longer-term basis, blood thinners in a pill form — Coumadin or its generic equivalent, warfarin — are prescribed.

Are there new drugs?

There are four new blood thinners, called direct oral anticoagulants, that have been studied over the past 10 years and are available for use worldwide. They are just as effective as Coumadin and warfarin, and they have a better safety profile. Plus, these drugs don't require any blood testing for monitoring, they have no food restrictions and less interactions with other medications. [However, the new drugs are significantly more expensive: according to GoodRx.com, a 30-day supply of Coumadin averages around $10 at retail, compared with more than $400 for Xarelto, one of the new blood thinners.]

Still, everybody sees the ads on TV from legal firms. They're pretty intense, suggesting there could be settlements for bleeding problems from these new drugs. It's not that people have more bleeding episodes on these drugs than on Coumadin or warfarin. The intent is to get clients. These new drugs really are safer, and I'm worried people will be afraid to use them.

Another issue is an effective antidote if the patient has a life-threatening bleed. Warfarin and Coumadin work by blocking Vitamin K metabolism in the liver, which is essential to making the body's clotting factors. People think that if you eat spinach or other green vegetables high in Vitamin K, or you take a Vitamin K pill, you immediately reverse the warfarin. It takes 24 hours to have an effect. Even if you give Vitamin K intravenously, it takes 12 hours. If someone has life-threatening bleeding on warfarin or Coumadin, blood products are available to rescue the patient from the life-threatening bleed.

One of the direct oral anticoagulants has a true antidote. It's given intravenously and it instantly reverses the effect of that blood thinner. Another antidote that is not yet approved by the Food and Drug Administration, but I expect it will be in a few months, will reverse the effects of all these direct oral anticoagulants. These new antidotes will be a major factor in the increased use of the direct oral anticoagulants in the U.S.

Are there risk factors for DVT and PE?

I believe that public awareness of the signs and symptoms of deep vein thrombosis and pulmonary embolism is important for early diagnosis and treatment. The signs and symptoms of DVT include discomfort, heaviness, pain, aching, throbbing, itching, or warmth in the legs and swelling. For pulmonary embolism, sudden onset of shortness of breath, chest pain, coughing up blood, and rapid or irregular heart rate are the signs and symptoms. Risk factors for deep vein thrombosis and pulmonary embolism are age, immobilization, trauma, cancer, surgery, obesity, pregnancy, increased estrogen levels (due to oral contraception or hormone replacement therapy), hereditary clotting disorders, and smoking.

My recommendation is that any time you experience any one of the above signs or symptoms and have risk factors for deep vein thrombosis or pulmonary embolism, seek medical care immediately. Don't wait for the symptoms to get better or go away. They won't.

Are there any other new developments besides the new drugs?

There's a new national organization called PERT (Pulmonary Embolism Response Team) Consortium. The group is focused on early assessment and diagnosis of acute pulmonary embolism and the appropriate therapeutic intervention to improve outcomes and reduce mortality. In addition, the organization maintains a patient database to measure outcomes and improve the quality of care for this disease. It has partnered with other patient advocacy organizations such as the North American Thrombosis Forum and Stop the Clot.

This is a whole new concept that's making a major impact on emergency departments and hospitals:   early diagnosis, appropriate treatment, and long-term care to improve patient outcomes.