Monitoring Pulse Post-Stroke Can Help Patients Detect Potential Atrial Fibrillation

New research suggests that most patients who have suffered a stroke can be taught to reliably detect the first signs of atrial fibrillation by measuring their peripheral pulse at the radial artery.

Authors of the German study, who published their findings in Neurology, found that the 89% of patients who completed a tutorial in the measurement of peripheral pulse (MPP) performed the technique well enough to achieve diagnostic sensitivity rates averaging 54.1%.

That figure is significantly lower than the typical diagnostic sensitivity of health care professionals (96.5%) and even relatives who are trained in the technique (76.5%) but it’s high enough to qualify as a valuable “first-step” screening tool.

"MPP offers an easy, ubiquitously available, noninvasive, first-step screening tool to guide ECG diagnostics for the detection of paroxysmal atrial fibrillation after ischemic stroke," wrote the study authors, who noted that the ease of teaching the technique is another advantage.

The study authors saw particular value in teaching MPP to people who had just suffered cerebral ischemia because that condition often triggers AF in patients who have never before suffered from irregular heartbeat.

Those first few bouts of AF come and go so quickly that they often elude detection by medical professionals during both the short-term and long-term treatment that follows an initial stroke.

Some research has investigated the idea of using implantable or external heart-rate monitors for such patients, the study authors noted, but questions about the cost and efficacy of such strategies will likely prevent widespread adoption, at least in the near term.

MPP, on the other hand, is always available, free of charge, to anyone who learns it.

To see how well stroke victims can learn the technique, researchers provided one or two tutorials to 220 mentally competent stroke patients (and any interested relatives who happened to be around).

Just 24 of the patients failed to complete the tutorial and those patients tended to be both older than those who learned the material (73.9 years vs. 68.3 years) and the victims of significantly more severe strokes.

Patients who completed the training and then used the technique to assess their own pulses achieved a sensitivity of 54.1% and a specificity of 96.2%. There were 6 (2.7%) false-positive results and 17 (7.7%) false-negative results, leading the research team to calculate the positive predictive value (PPV) as 76.9%, and the negative predictive value (NPV) as 90%.

Relatives who completed the tutorial fared even better in most ways. They achieved a sensitivity of 76.5%, and a specificity of 92.9%. Researchers calculated their PPV at 78.8% and their NPV at 91.9%. Healthcare professionals, as expected, did better still. They achieved a sensitivity of 96.5% and a specificity of 94%. Their PPV was 82.1%, and their NPV was 98.9%.

The researchers noted several limitations to their study, including the number of patients, the use of only one treatment facility, the timing of the intervention and the exclusion of other arrhythmias.

Still, they concluded, the study did provide Class I evidence that patients and their relatives can quickly learn how to use MPP to distinguish normal heart beats from AF.