New preliminary research is suggesting a simple saliva test can detect the presence of a protein biomarker known to signal the occurrence of a heart attack in just 10 minutes. If this prototype test is validated in future studies it could dramatically accelerate the speed at which patients with cardiovascular problems can be diagnosed and treated.
During a myocardial infarction, commonly known as a heart attack, levels of a protein called troponin rapidly rise in a patient’s blood stream. Not every heart attack is immediately apparent. Symptoms such as chest pain, nausea and fatigue can be frustratingly non-specific, so when a patient presents to an emergency room with these signs doctors will quickly perform a blood test to measure troponin levels. The blood test generally takes around an hour to return a result.
“There is a great need for a simple and rapid troponin test for patients with chest pain in the pre-hospital setting,” explains study author Roi Westreich, from Soroka University Medical Centre in Israel. “Currently troponin testing uses blood samples. In this preliminary study we evaluated the feasibility of a novel method using saliva.”
The research began by taking commercially available troponin blood tests and finding ways to adapt them to detect the protein in saliva samples. A novel processing procedure was developed to remove a number of superfluous proteins from saliva samples.
Saliva samples were taken from 32 heart attack patients with confirmed blood troponin results. Control saliva samples were also taken from 13 healthy subjects.
The initial results proved promising, with the processed saliva samples from the heart attack patients testing positive for troponin 84 percent of the time. Only six percent of the unprocessed saliva samples tested positive for troponin, suggesting the processing procedure is vital in concentrating the saliva samples for effective results. It is unclear at this stage what the “processing” procedure entails, or how easy and affordable it is.
The researchers suggest the saliva test will take just 10 minutes to deliver results. And, while more validation work is necessary, the test could offer those with poor cardiovascular health a significantly helpful new diagnostic tool. Westreich says the test would ultimately work in the same way as a pregnancy test, delivering simple positive/negative results in minutes.
“This early work shows the presence of cardiac troponin in the saliva of patients with myocardial injury,” says Westreich. “Further research is needed to determine how long troponin stays in the saliva after a heart attack. In addition, we need to know how many patients would erroneously be diagnosed with heart attack and how many cases would be missed.”
The new research is yet to be published or peer-reviewed but was recently presented at the European Society for Cardiology Annual 2020 Congress.
Spit test promises to diagnose heart attacks in just 10 minutes [New Atlas]