NEW YORK (Reuters Health) – Rapid fluid replenishment “remarkably” improves the detection rate of patent foramen ovale (PFO) by transesophageal echocardiography, a multicenter team reports in the American Journal of Cardiology online August 13.
The authors explain that patients being examined for suspected PFO are often hypovolemic due to pre-procedural fasting, and this might reduce interatrial pressures so that right-to-left shunting is not apparent.
To see if rapid fluid replacement might unmask a PFO in this setting, Dr. Luis Afonso at Wayne State University, Detroit, Michigan and colleagues analyzed the diagnostic yield in 103 patients being examined by transesophageal echo.
As described in the report, “All patients underwent a series of agitated saline bubble injections (with and without provocative maneuvers) before and after an intravenous saline bolus.” The investigators found that the PFO detection rate increased from 10.6% to 26.2% after saline loading. When combined with a Valsalva maneuver or cough to provoke shunting, fluid loading increased the detection rate from 17.4% to 32.0%.
The saline bolus resulted in the “de novo diagnosis of PFO in 15 patients, atrial septal aneurysm in 15, PFO coexisting with an ASA in 10, and pulmonary arteriovenous fistulas in 5 patients,” the researchers report.
They saw no complications from saline loading.
“Our findings are compelling and suggest that fluid repletion significantly improves PFO detection rates in patients undergoing TEE,” Dr. Afonso commented in an email to Reuters Health. “Although not specifically ascertained in this study, our findings could have potentially profound implications in patients undergoing TEE for suspected PFO’s or cardiac source of embolus.”
However, Dr. Afonso indicated that it is too soon to recommend that the protocol become routine. “While we have adopted the fluid loading protocol in patients referred for TEE with suspected PFOs, additional prospective data examining the impact of saline loading on PFO detection in this subset of patients is needed.”
Reference:
Usefulness of Intravenously Administered Fluid Replenishment for Detection of Patent Foramen Ovale by Transesophageal Echocardiography
Am J Cardiol 2010.
