Diagnosis and Evaluation of Orthostatic Hypotension

Diagnostic Criteria

The American College of Cardiology defines orthostatic hypotension as a systolic blood‑pressure drop ≥ 20 mmHg or a diastolic drop ≥ 10 mmHg within 3 minutes of standing after 5 minutes of supine rest【1】.
In patients with supine hypertension, a larger systolic drop ≥ 30 mmHg may be more clinically relevant【1】.

The Canadian Cardiovascular Society recommends that patients lie supine for 5 minutes before measuring blood pressure and heart rate【2】.
Blood pressure and heart rate should be recorded at 1 minute after standing to detect initial orthostatic hypotension and at 3 minutes to detect classic orthostatic hypotension【1】.
If symptoms persist or suspicion remains high, measurements may be continued up to 10 minutes to identify delayed orthostatic hypotension (onset > 3 minutes)【1】.

Initial orthostatic hypotension: a rapid drop > 40 mmHg systolic or > 20 mmHg diastolic within 15 seconds of standing, with spontaneous recovery in < 40 seconds【1】.
Classic orthostatic hypotension: a sustained drop meeting the standard criteria (≥20 mmHg systolic or ≥10 mmHg diastolic) within 3 minutes of standing【1】.
Delayed orthostatic hypotension: a qualifying blood‑pressure drop that occurs after 3 minutes of standing【1】.

The American College of Cardiology recommends head‑up tilt‑table testing at ≥60° when the patient cannot stand safely, when bedside findings are normal but clinical suspicion remains high, or when a detailed autonomic assessment is required for refractory cases【1】【2】.
Tilt‑table testing should not be performed routinely; it is reserved for complex diagnostic clarification【2】.

After confirming orthostatic hypotension, a blunted heart‑rate increase (< 15 bpm) despite the blood‑pressure drop suggests neurogenic orthostatic hypotension, indicating autonomic dysfunction【1】.

Comprehensive autonomic evaluation (e.g., Valsalva maneuver, deep‑breathing tests, plasma catecholamine measurement) should be reserved for refractory cases or when autonomic neuropathy is suspected, rather than ordered routinely【2】【1】.