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Wise Buy, a 番茄社区 series, assesses therapies -- new and old -- to determine if the treatment is not only a wise choice, but also a wise buy.
It's been nearly 35 years since Barney Clark, a Seattle dentist, became the first recipient of a permanent, total artificial heart, a milestone that attracted huge attention from the press and the public and promised to revolutionize the treatment of heart failure.
Sadly, however, the mechanical heart did not deliver on its promise. Clark lived for 112 days, tethered to a 400-pound, refrigerator-size compressor. Several more patients received implants with mixed results, none of them acceptable. The future of the artificial heart seemed bleak.
Research continued, however, on devices to help failing hearts rather than replace them. The idea was to boost the heart's function, and patients' health, by taking over some of the demanding work of the left ventricle. These left ventricular assist devices -- referred to as LVADs or sometimes VADs -- have attracted far less attention than heart transplants, presumably because giving a heart a boost is less awe-inspiring than replacing it.
But this is where the action is. LVADs are getting better and cheaper, and their developers expect that one day they will rival heart transplants as a treatment for advanced heart failure.
When, or if, that day comes, the outlook for patients with advanced heart failure will change forever. Heart transplants are an effective treatment. Half of the patients who get transplants are alive 10 years later. But fewer than 1% of the nearly 250,000 Americans with advanced heart failure . Only 2,200 transplants are done each year, because of the severe shortage of donor hearts.
LVADs, in contrast, roll off an assembly line. Manufacturers can produce as many as needed to meet demand. If LVADs begin to match the success of heart transplants, many more patients could be helped. But at what cost? And who will pick up the check?
Research on LVADs , when the noted cardiologist Michael E. DeBakey of the Baylor College of Medicine in Houston implanted one in a 37-year-old woman with aortic insufficiency and mitral stenosis. The pumps available at that time were outside the body, and they could be used for only a short period of time because of the high risk of thrombosis, bleeding, infection, and pump malfunction. Work continued with the development of implantable pulsatile pumps, connected to a power source through an external drive line. That decreased the risk of infection, but didn't eliminate it.
LVADs were not used widely until 2001, when a study known as the appeared in the New England Journal of Medicine. It concluded that the use of an LVAD in patients with advanced heart failure "resulted in a clinically meaningful survival benefit and an improved quality of life." The key finding was that 23% of the very sick patients in the study survived 2 years. In the control group, given only medical therapy, only 8% survived 2 years.
"That was a turning point," says Dipanjan Banerjee, MD, MS, a cardiologist and heart-failure specialist at Stanford University. "It really established that LVAD therapy was viable." That study used old-style pulsatile LVADs that pumped blood like the heart does, one push after another.
The takeaway was the LVADs were recognized as a valuable bridge-to-transplant option, but still unknown was their utility as destination therapy.
The second landmark study, he says, appeared in the NEJM in 2009. That study used newer continuous-flow pumps, which provide a steady push with a propeller-like rotating screw. Researchers were abandoning the pulsatile pumps for the sleeker, quieter continuous-flow models -- just as early flying enthusiasts discarded their wing-flapping contraptions in favor of fixed-wing aircraft. In the , at 2 years 58% of patients given the new LVADs were alive versus a 24% 2-year survival rate for the pulsatile pumps. "That's when things took off," said Banerjee. Stanford launched its LVAD program the following year.
That 2009 study established LVADs as a legitimate destination therapy.
LVAD therapy is now so successful that some doctors are using it in patients that don't need it, Banerjee says. The risk there is that the patients might experience, say, the liver and kidney problems associated with LVADs -- without getting much benefit. "The cat is out of the bag. We're already seeing people putting LVADs in patients who are not that sick," he says. "We go by the original guidelines in our hospital. They have to be really sick."
He and his colleagues recently published a s. They found that it improved quality of life but increased lifetime costs. They calculated that the lifetime costs of LVAD treatment would be $726,200, compared to $361,800 for patients given medical treatment. Those figures included the cost of installing an LVAD -- about $175,000 -- and the costs of hospital readmissions and outpatient care. "There is a sweet spot. You can be too well for an LVAD. But you can also be too sick," Banerjee says.
LVAD treatment in these patients extended life, but at a cost of $210,000 per quality adjusted life year (QALY). "The value isn't there," says Jacqueline Baras Shreibati, a cardiologist formerly at Stanford and a co-author of the study.
Joseph G. Rogers, MD, a cardiologist at Duke University who wrote an editorial accompanying the study, said treatments that cost less than $50,000 per QALY are considered cost-effective, and under $100,000 is tolerable. If doctors can bring down readmission costs and outpatient treatment costs, however, the use of LVADs in these patients "can actually get to a range that begins to look cost-effective," he says. Rogers notes that costs have already come down dramatically. In the early 2000s, it was $800,000 per QALY saved, compared to $210,000 now.
The move to use of LVADs in less-sick patients is surely driven by doctors' desire to offer something helpful to their patients. But there may be another factor at work, says Banerjee. "There is a financial incentive to do procedures. Hospitals are eager to do more."
Oddly, Banerjee also finds that some doctors and hospitals are denying LVADs to patients who could benefit from them. "They are putting people into hospice when it needn't happen," he says. Why? Often because cardiologists are not familiar with them; LVADs were not widely used when cardiologists who are now middle-aged did their training, Banerjee says.
So: Is an LVAD a wise buy?
"From whose perspective?" Rogers asks. "If you're a patient, we've been able to demonstrate in clinical trials that if you progress to the point where you need IV medication, LVADs improve longevity, quality of life, and functional capacity -- your ability to perform the activities of daily living. If your goal is to live longer and better, and if you're a candidate -- absolutely!"
For insurers and the government, the answer might be different, he says. "It currently doesn't meet the definition of cost-effectiveness, but it's moving in the right direction." In five to 10 years, it will rival heart transplantation, he says, prolonging life with fewer complications.
Shreibati agrees. "From the patient's perspective, this is a very wise buy." But giving LVADs to the 250,000 patients who could use them would cost $36 billion a year -- about 6% of Medicare's budget. "If I were in Washington, I would not say this was a wise buy."
The situation is likely to change. Newer pumps are on the way that have fewer moving parts and thus should be more reliable. Banerjee suspects that more companies will enter the LVAD market, driving costs down and encouraging innovation.
LVADs will never be a bargain, but, says Banerjee, they need better press. "For cancer, we don't bat an eye to add even two months of life" with very expensive new drugs, he says. "LVAD therapy is expensive, but it allows you to prolong life for much longer that some of the newer cancer drugs," he says. The problem, he suspects, is marketing.
"The marketing of heart failure has not been as good as cancer." Nobody wears pink ribbons for heart failure.