Fractional Flow Reserve
Fractional Flow Reserve - Related Videos
01:27
Fractional-Reserve Banking I
0 Views •
2025
Fractional-reserve banking is a system in which banks hold only a portion of the deposits they receive as reserves, while the rest is made available for lending. To understand how this works, imagine a hypothetical economy. Assume that the entire money supply is deposited in banks for safekeeping. Each bank keeps aside a share of deposits as reserves and lends out the remaining amount.In a bank's balance sheet, money deposited is recorded as a liability because the bank owes it to the depositor.
01:19
Fractional-Reserve Banking II
0 Views •
2025
Fractional-reserve banking is a system in which banks are required to hold only a portion of their deposits as reserves, while the rest can be loaned out. Even if a bank lends from a deposit, the bank still owes the full deposit amount to its lenders. So, the original deposit remains a liability on the bank’s balance sheet. The bank’s assets include its reserves and the loans it makes.As loans are made and re-deposited into other banks, this creates a cycle in which each bank lends a portion of...
06:39
Ultrasound Based Assessment of Coronary Artery Flow and Coronary Flow Reserve Using the Pressure Overload Model in Mice
0 Views •
Cited by 20 •
2015
Coronary flow reserve (CFR) is useful for assessment of myocardial oxygen demand and evaluation of cardiovascular risk. This study establishes a step-by-step transthoracic Doppler echocardiographic (TTDE) method for longitudinal monitoring of the changes in CFR, as measured from coronary artery in mice, under the experimental pressure overload of aortic banding.
06:32
Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats
0 Views •
Cited by 12 •
2019
Coronary flow reserve (CFR), is defined as the ratio of maximal coronary blood flow to the resting coronary blood flow. We present a protocol for evaluating CFR in rats via ultrasound, which offers the opportunity to predict cardiovascular risk factors in the absence of obstructive coronary disease.
01:18
Excess Reserves
0 Views •
2025
Excess reserves, while often viewed as idle funds from a lending perspective, play a vital role in ensuring financial stability and managing risk—particularly during periods of economic uncertainty or regulatory change.Strategic Value Beyond LiquidityExcess reserves are not merely a liquidity buffer; they represent a deliberate strategic decision by banks. When economic conditions are stable, lending typically yields higher returns. However, during periods of financial volatility or increased...
FAQs
Maximal coronary hyperemia creates a standardized state in which the pressure relationship across a coronary narrowing can be assessed. Adenosine is typically used to induce this increased coronary blood flow during catheterization. Measuring under hyperemic conditions helps reveal whether the stenosis produces a pressure reduction consistent with impaired blood supply to the downstream heart muscle.
Angiographic imaging shows the appearance and estimated severity of a coronary narrowing, whereas Fractional Flow Reserve provides physiological information about its effect on blood flow. Comparing these perspectives helps clinicians determine whether a visible lesion is actually flow limiting. This distinction can support treatment decisions when the anatomical image alone does not establish the lesion's clinical importance.
An FFR value of 0.80 or lower generally indicates that the measured coronary narrowing is limiting blood flow enough to suggest ischemia. The value comes from the ratio of distal coronary pressure to aortic pressure during maximal hyperemia. Clinicians can use this physiological threshold to identify lesions more likely to benefit from revascularization.
The assessment takes place during cardiac catheterization. Clinicians measure pressure in the aorta and at a point beyond the coronary stenosis, then induce maximal coronary hyperemia, typically with adenosine. They calculate the distal coronary pressure-to-aortic pressure ratio and interpret the result to determine whether the narrowing produces a flow-limiting physiological effect.
Adenosine is typically administered to induce maximal coronary hyperemia before the pressure ratio is interpreted. This condition is central to the measurement because it provides the physiological setting used to evaluate the stenosis. Without considering the hyperemic state, the recorded pressure relationship would not represent the standardized assessment described for Fractional Flow Reserve.
FFR can help determine whether a coronary lesion identified during angiographic evaluation is physiologically important enough to justify percutaneous coronary intervention. Lesions showing flow-limiting values are more likely to benefit from revascularization, while lesions without that indication may not require a stent. This supports decisions based on functional significance rather than appearance alone.
By combining physiological assessment with angiographic imaging, FFR helps distinguish lesions that limit blood flow from those that are merely visible on an angiogram. This information can identify patients and lesions more likely to benefit from revascularization while reducing unnecessary stent placement. Its clinical value lies in tailoring coronary artery disease management to the measured significance of each narrowing.