The PulSentry blog

Evidence-led writing on cardiac tamponade, pulsus paradoxus, and what a pulse oximeter waveform can reveal, for clinicians, and for anyone trying to understand the science.

Clinical explainer

What is pulsus paradoxus? A clinician's guide

The definition, how it is measured, the conditions it accompanies, when it is absent, and how the same signal appears on the pulse oximeter waveform.

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Clinical explainer

Why echocardiography misses post-surgical tamponade

After cardiac surgery, transthoracic echo is far less sensitive than many expect. What the evidence shows, and why the post-discharge window is a blind spot.

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Reimbursement

The 2026 Medicare RPM CPT code guide

99453, 99454, 99457, 99458, 99091, and the new 99445, what each pays, the day-count thresholds, and how short post-discharge monitoring fits.

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Technology

FFT and power spectral density of the PPG waveform, explained

How a pulse-oximeter signal is transformed into the frequency domain, and what the pulsus index measures.

Coming soon
Clinical explainer

Cardiac tamponade after cardiac surgery: incidence, timing, detection

How often it happens, when it presents, and which patients are most at risk.

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Expansion

Tamponade after Watchman, ablation, and transseptal procedures

Iatrogenic tamponade risk in structural-heart and electrophysiology procedures, and the monitoring window that matters.

Coming soon