Half of patients with pulmonary embolism can be treated at home: Hestia study

December 6, 2010 | Zosia Chustecka
Orlando, FL – Patients with pulmonary embolism (PE) are usually treated in the hospital, but the Hestia study from Europe suggests that about half could be treated at home, which would reduce costs, inconvenience, and also the risk of infection, using a simple questionnaire-based tool.

The “Hestia tool” also identifies which patients would be suitable for outpatient treatment, commented senior author Dr Menno Huisman (Leiden University, the Netherlands). He was speaking at a press conference during the American Society of Hematology (ASH) 2010 Annual Meeting, ahead of the presentation of the data in a late-breaking abstract on December 7.

“For cardiologists, I think the main message is that with our Hestia tool we can select a low-risk patient population that can be treated out of the hospital, defined by starting anticoagulant treatment within 24 hours of objective PE diagnosis; this means that a physician having applied the Hestia criteria in a patient can either send a patient home with a prescription of low-molecular-weight heparin and warfarin or take that patient in the hospital for a couple of hours,” Huisman told heartwire. “Most cardiologists seeing PE patients tend to see the sicker patients—that is, those with large clots in the lungs and with hemodynamic compromise; the patients we have selected are clearly the low-risk stable patients.”

Patients with PE are usually treated in the hospital and stay for an average of 10 days, but this study suggests that half could be treated at home with similar results, according to Dr Harry R Büller (University of Amsterdam, the Netherlands), who was not involved in the study.

“This is the best evidence yet that some patients with pulmonary embolism can be treated as outpatients,” commented ASH secretary Dr Charles Abrams (University of Pennsylvania, Philadelphia). Treatment at home is more convenient for the patient, he commented, and potentially safer, because being admitted to a hospital always exposes patients to potential infections and complications.

Which patients can go home?

Previous studies have suggested that PE could be treated at home instead of in the hospital, and this is done sometimes in practice, but not on a formal basis, Huisman explained. He noted that the 2008 guidelines from the American College of Chest Physicians concluded that home treatment is not generally recommended.

One of the problems is deciding which patients would be suitable for treatment at home and which are higher risk and need to be treated in the hospital, he said. To address this issue, his team developed the Hestia criteria, an 11-point questionnaire that evaluates patients for risk. In their study, only patients who met all 11 criteria were allowed to be treated at home, while the remainder were treated as inpatients.

Results similar to historical controls

For their study, Huisman and colleagues screened 581 patients with acute PE and found that 297 (51%) met the Hestia criteria and were treated at home.

They were sent home within 24 hours of being diagnosed with PE, and all received weight-adjusted therapeutic doses of low-molecular-weight heparin, followed by vitamin-K antagonists. After three months, six patients had recurrent venous thromboembolism (2%).

This was not a randomized trial, so there is no direct comparison between these patients and those who were treated in the hospital, Huisman said. But historical controls show a recurrence rate of 1% to 3% among inpatients, so the 2% seen in the patients treated at home is in the same range, he said.

There were three deaths in the three months after treatment, two from cancer and one from an intracranial hemorrhage, but this occurred in a patient with uncontrolled hypertension, Huisman said. In addition, two patients experienced major bleeding (0.7%). This also compares favorably with historical controls of patients treated in the hospital, he commented.

“Results from this study show that the Hestia criteria are efficacious and safe in helping doctors determine which acute PE patients can receive outpatient anticoagulant treatment safely,” Huisman concluded.

However, when asked if clinicians should go ahead and use the Hestia criteria in practice, he was hesitant. “Not yet, but we are coming close to closing the gap,” he said.

The next step will be validation in a randomized trial, which is already planned. Known as Vesta, it will take about one to two years to carry out, so results should be available in about 2.5 years, he said.

The names of both trials are taken from mythology, “because I hate acronyms,” Huisman said. Hestia is the Greek goddess of the home, and Vesta is the Roman equivalent.

The Hestia criteria

Triaging for outpatient treatment of PE was carried out using the following 11-point questionnaire. Only patients for whom the answer was “no” to each question were allowed to be treated at home; if even one question was answered with a yes, they remained in the hospital.

  • Is the patient hemodynamically unstable?
  • Is thrombolysis or embolectomy necessary?
  • Active bleeding or high risk for bleeding?
  • More than 24 hours of oxygen supply to maintain oxygen saturation >90%?
  • Is pulmonary embolism diagnosed during anticoagulant treatment?
  • Severe pain needing intravenous pain medication for more than 24 hours?
  • Medical or social reason for treatment in the hospital for more than 24 hours (infection, malignancy, no support system, etc)?
  • Does the patient have a creatinine clearance of less than 30 mL/min?
  • Does the patient have severe liver impairment?
  • Is the patient pregnant?
  • Does the patient have a documented history of heparin-induced thrombocytopenia (HIT)?