Yes doctor…I understand the procedure, but what is the risk
While most vascular procedures are so minimally invasive that the risks are quite low
, especially procedures on veins
However, the risk increases significantly, when we get into vascular problems involving
carotid artery stenosis
(narrowing of the arteries in the neck which can cause strokes
(ballooning of the blood vessels which can burst and cause instantaneous death) or
severe shortage of blood supply to the lower legs – leg ischemia
In such cases, aside from the risks inherent to the part of the body where the operation is being performed, the main risk is to the heart – “Heart attack
” as most of folks lump all things heart related.
The risk is not only related to “what” the risk is, but “how much” is the risk? This “quantification” of the risk is important so that measures can be taken to “reduce risk”.
Why all the fuss…..because anybody having a heart attack or heart failure
around the time of an operation has a 30% - 50% chance of dying.
So to “risk stratify” patients several indices have been developed. The Goldman Risk Index
was developed in the 1970’s, but the limitation was that when they made this index, they did not include very many vascular patients in the original study and so this index is not focused on vascular patients.
To overcome this limitation, the Eagle’s Cardiac Risk Index
was devised for patients undergoing vascular surgery.
Multivariate analysis has shown that the following factors predict an adverse event following vascular surgery:
- Q waves on the electrocardiogram (ECG)
- History of angina pectoris
- History of ventricular ectopy requiring treatment (most specific for predicting events)
- Diabetes mellitus requiring therapy other than diet
- Age older than 70 years
- Thallium redistribution (most sensitive for predicting events)
- Ischemic electrocardiographic changes during or after dipyridamole infusion
Combining both the clinical data and thallium imaging was more sensitive and specific than either alone in predicting postoperative complications. In this model, the following can be noted:
- No clinical predictors of risk factors: 3.1% risk of perioperative ischemic cardiac complications
- Thallium redistribution in addition to one or two clinical predictors: 29.6% risk of perioperative complications
Three clinical predictors: 50% risk of perioperative cardiac complications
More recently, the Vascular Study Group of New England
has developed the Vascular Study Group Cardiac Risk Index (VSG – CI) for the patients mentioned at the beginning of this article. This is the current Standard used by vascular surgeons at most academic medical centers.
This is the current risk calculator used by us at Vascular.ae, across all our practices in the Middle East.