HesapHanem

TIMI Frame Count Calculator

Enter the frames counted and cine frame rate to get the corrected TIMI frame count.

Result

24.0 frames
0.80 s
Normal (≤28)

How it is calculated

The tool takes the number of cine frames you counted and the frame rate of the recording. CTFC = frames × (30 / fps) converts the count to what it would be at 30 frames per second, and flow time = frames / fps gives the real time in seconds. If you leave the frame rate empty, 30 is used; a frame rate of 0 or less, or zero frames, gives no result. The label is "Normal (≤28)" when the CTFC, rounded to the one decimal shown on screen, is 28.0 or lower, and "Slow flow (>28)" above that. The tool only corrects for the frame rate: it applies no vessel-specific correction, so if your protocol adjusts the count for the artery, do that to the frames first. The 28 cut-off is the one built into the tool; use your own protocol's limits for clinical decisions. It is for reference, not a diagnosis.

Worked example

Contrast takes 12 frames to reach the distal landmark on a run filmed at 15 frames per second. The correction factor is 30 / 15 = 2, so CTFC = 12 × 2 = 24.0 frames. The real flow time is 12 / 15 = 0.80 s. Since 24.0 is not above 28, the tool labels it "Normal (≤28)". The same 12 frames at 30 fps would be a CTFC of only 12, which shows why the frame rate has to be entered.

Try this example →

Common mistakes

  • Leaving the frame rate at its default 30 when the run was filmed at 15 fps. The CTFC is then half of the true value and slow flow can look normal.
  • Entering the time in seconds in the frames box. The field takes a frame count; the time is calculated for you.
  • Starting or stopping the count at the wrong frame. Use the same start and end landmarks every time, otherwise values from different studies cannot be compared.
  • Expecting a value just above 28 to read as normal. The label follows the rounded value shown: a count that displays 28.0 is labelled Normal, while one that displays 28.1 is labelled Slow flow.
  • Expecting the tool to correct for vessel length. It scales for frame rate only, and any vessel-specific factor must be applied before you enter the frames.

Sources

About this calculator

The corrected TIMI frame count (CTFC) is an angiographic method for objectively quantifying coronary blood flow, developed as a more precise alternative to the subjective TIMI flow grade (0–3). It counts the number of cine frames from contrast entering the coronary artery until it reaches a standardized distal landmark, then corrects for the cine frame rate. This calculator applies that frame-rate correction (frames × 30 ÷ fps) to the count you enter; it does not adjust for the vessel's length.

A lower frame count means faster, healthier flow; a higher count indicates sluggish flow, as seen in conditions like coronary microvascular dysfunction or slow-flow phenomenon. Interventional cardiologists use CTFC in the cath lab and in research to grade flow before and after procedures like angioplasty, assess the success of reperfusion therapy, and compare flow objectively across patients and studies. In Gibson et al.'s original 1996 study, normal arteries averaged about 21 ± 3 corrected frames, and studies of coronary slow flow commonly use a corrected count above 27; the tool's 28 cut-off is its own simplified label, so follow your laboratory's protocol.

Was this helpful?

You can pick up to 3 reactions.

Comments (1)

  • Editorial team

    A quick consistency check: the corrected count always equals 30 times the flow time in seconds. For 35 frames at 30 fps the tool shows 1.17 s and a corrected count of 35.0, and at 15 fps the same 35 frames become 70.0. The result is a single number for one vessel, and its meaning belongs to the cardiologist. At what frame rates are the runs you work with usually recorded?

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators