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Verified on Base

This article has not changed since Vitahash recorded it on the Base blockchain. Everything below can be checked without taking our word for any of it.

🧠 POTS: WHY DOES IT HAPPEN?

Chayakrit Krittanawong, MD, FACC, FAHA, FSCAI · 2 Oct 2026

Stamp ID
STAMP-2026-1002-7ZFP3Q6L
Content hash
44ab3f8181f182d08d79bfd0e88e36cad865dfd964e4cbbbf12cce0c02f23775
Day recorded
2026-10-02
Articles recorded that day
15
Attestation UID
0xef3f22b3a9cc55958e4755465862526112b92e627f89ef9d8fc67aebc0e4a464
View on EAS
Transaction
0x0d04c42c85b7d9a5baf2c56ea619729fbe1338337d06aa5eaeb77eec61dd1106
View on Basescan
Stamped
2 Oct 2026

Recorded on Base using canonicalization v2 and record format v1.

How this article reaches the blockchain

It was combined with the other 14 articles published that day, one step at a time, until the whole day became a single value. That one value is what Vitahash wrote to the blockchain. Change a single character of this article and the starting value below changes, so none of the steps would land on the recorded one.

Starting value for this article
0x904fff19ede3ebcaa7fe81ef67c42ce99fc5700b544c32bdc0e8ccc0f0ffd83f

Built from this article's content hash and its stamp ID, as sha256(0x00 || sha256(utf8(stampId)) || contentHash).

  1. Step 1, combined with the value before it
    0xb7ff567ea3efa03542a18eaf5e3e03de607a1f8ea2bce6ef4ff4be043bbf45e7
    0x6b17fa00dc5a05b786727d7f1507bb5691613449fcc4c0d64cd128eaa302a7af
  2. Step 2, combined with the value before it
    0xeb8210bfc9028909f9510e6a54d2e243c07f3044742c9698d32d3203b0d43cb0
    0x2cd72d4bd66df07a63b5db20323f0e99df25a5f1df376f001cb13ac09996869a
  3. Step 3, combined with the value before it
    0x69b963a72ff774db15166fbf612b296d701fe32a57f181d9635950a5c9b83208
    0x66fc8ec21a31705c4be9de3e933ca15d28787982a4d8b647c0bd15af650a3d3e

    This is the value for the whole day.

Value these steps arrive at
0x66fc8ec21a31705c4be9de3e933ca15d28787982a4d8b647c0bd15af650a3d3e

What the blockchain says

Two values, reached two different ways. The one above was worked out from this article. The one below was read back from the record on Base.

Worked out from this article
0x66fc8ec21a31705c4be9de3e933ca15d28787982a4d8b647c0bd15af650a3d3e
Read from Base
0x66fc8ec21a31705c4be9de3e933ca15d28787982a4d8b647c0bd15af650a3d3e
Read it yourself on EAS

They are the same value, so this article was published that day with exactly the text above.

Check it yourself

Every number on this page came from Vitahash. Copy the article's exact text below and check it against the hash above, using any SHA-256 tool.

{"abstract":null,"agreement":false,"authors":[{"identity":"Drkrittanawong","position":1,"role":"solo","weight":1.0000}],"body":{"content":[{"content":[{"text":"Postural Orthostatic Tachycardia Syndrome (POTS) is more than just a fast heart …

Copy this text, paste it into any SHA-256 tool, and compare the result with the hash shown above. If the two match, this is exactly what Vitahash recorded.

For a technical reader: the terminal route

  1. 1. Hash the article yourself

    This downloads the exact text Vitahash hashed, in the exact form it hashed it, and hashes it again on your machine. Nothing Vitahash wrote runs here.

    curl -s "https://api.vitahash.org/api/verify/STAMP-2026-1002-7ZFP3Q6L/canonical" | shasum -a 256

    Should print 44ab3f8181f182d08d79bfd0e88e36cad865dfd964e4cbbbf12cce0c02f23775

  2. 2. Build this article's starting value

    The stamp ID is folded in with the hash, so one article's record can never stand in for another's.

    STAMP=STAMP-2026-1002-7ZFP3Q6L CONTENT=44ab3f8181f182d08d79bfd0e88e36cad865dfd964e4cbbbf12cce0c02f23775 DIGEST=$(printf '%s' "$STAMP" | shasum -a 256 | cut -d' ' -f1) printf '00%s%s' "$DIGEST" "$CONTENT" | xxd -r -p | shasum -a 256

    Should print 904fff19ede3ebcaa7fe81ef67c42ce99fc5700b544c32bdc0e8ccc0f0ffd83f

  3. 3. Combine step 1

    The published value goes first, then the value you have.

    printf '01%s%s' "b7ff567ea3efa03542a18eaf5e3e03de607a1f8ea2bce6ef4ff4be043bbf45e7" "904fff19ede3ebcaa7fe81ef67c42ce99fc5700b544c32bdc0e8ccc0f0ffd83f" | xxd -r -p | shasum -a 256

    Should print 6b17fa00dc5a05b786727d7f1507bb5691613449fcc4c0d64cd128eaa302a7af

  4. 4. Combine step 2

    The published value goes first, then the value you have.

    printf '01%s%s' "eb8210bfc9028909f9510e6a54d2e243c07f3044742c9698d32d3203b0d43cb0" "6b17fa00dc5a05b786727d7f1507bb5691613449fcc4c0d64cd128eaa302a7af" | xxd -r -p | shasum -a 256

    Should print 2cd72d4bd66df07a63b5db20323f0e99df25a5f1df376f001cb13ac09996869a

  5. 5. Combine step 3

    The published value goes first, then the value you have.

    printf '01%s%s' "69b963a72ff774db15166fbf612b296d701fe32a57f181d9635950a5c9b83208" "2cd72d4bd66df07a63b5db20323f0e99df25a5f1df376f001cb13ac09996869a" | xxd -r -p | shasum -a 256

    Should print 66fc8ec21a31705c4be9de3e933ca15d28787982a4d8b647c0bd15af650a3d3e

  6. 6. Compare with the blockchain

    The last value above is what the whole day came to. Read the record on Base and check its merkleRoot field is the same. Vitahash is not involved in this step at all.

    https://base.easscan.org/attestation/view/0xef3f22b3a9cc55958e4755465862526112b92e627f89ef9d8fc67aebc0e4a464

The rules these commands follow are written down in full, so anyone can reimplement them.

Read the specification