TASC II

Peripheral artery disease (PAD) has been severely underestimated for many years; physicians often considered it as a minor problem without any major consequences. Yet, there is vast evidence that PAD is accompanied by a considerable risk to develop cardiovascular complications. It is one of the essential goals of TASC II to focus attention on this issue.

TASC II (1) is an update of a previous document published in 2000 at the time of the world congress of Angiology in Ghent, Belgium. It is authored by vascular experts of all disciplines (medical, interventional...) and includes an update of the CoCaLis document (2). TASC II provides the reader with a critical review of the literature on all important chapters of arterial disease in the legs. It contains many tables with recommendations ranked according to the level of scientific evidence. A few of the main messages are summarised below.

PAD is a major risk for developing cardiovascular complications

PAD is accompanied by a severe increase in mortality; this is not due to whatever problem in the limbs but rather to coronary or cerebral vascular disease (2). This was recently confirmed by the REACH study (3), a large multicentre registry; the data of REACH allowed PAD to be seen as a risk condition of the same order of magnitude as angina pectoris. Adding some other risk factors, one quickly comes to a total cardiovascular risk that is frighteningly high; this is the case in many PAD patients. This message is one of the essentials of TASC II and should be clear in every physician's thinking.

PAD is easy to detect

Knowing the very high risk patients with PAD run, there is a strong argument to detect these patients in the population. It is easier to do with PAD than for many clinical other conditions. We should not neglect the great value of clinical examination. If foot pulses are present, the chances are good that circulation higher up (femoral, iliac arteries), is patent. Unfortunately, many physicians are not trained anymore or lost their skills to perform palpation of arterial pulses. In that case, ankle-brachial artery pressure index (ABI) determination is a superb tool to help very efficiently. In the context of the vascular clinic, the technique provides a specificity of almost 100 % and sensitivity of 90-95 %. It is easy to perform, painless, afordable and does not cause any harm! Normal ABI values range between 0.9 and 1.3: the lower under 1 it falls, the more severe is the degree of vascular obstruction. False high indexes are seen in patients with increased arterial stiffness as often occurs in patients with diabetes or in elderly patients.

The indications to perform an ABI according to the TASC II recommendations, are listed in table 1.

Table 1. Indications to perform and ankle-brachial artery pressure index (ABI) (1)
 

ABI should be performed in all patients:

• With exertional symptoms in the legs
• between the age of 50 and 69 years, who have a cardiovascular risk factor (particularly diabetes or smoking)
• Aged 70 years or more, irrespective of risk factor status
• Who have a Framingham (or SCORE) risk score between 10 and 20%

ABI not only allows to determine the degree of vascular obstruction; it also allows to estimate total cardiovascular risk; there is a step by step correlation between long term prognosis and ABI. This again highlights how much PAD carries an increased risk for cardiovascular morbidity and mortality.

Cardiovascular risk of PAD patients can be controlled.

A lot can be done to decrease the high cardiovascular risk of PAD patients. The first step is life style adaptation taking care of all available cardiovascular risk factors.
Antiplatelet drugs do help to decrease risk; the simplest and affordable drug, is low dosed aspirin. Clopidogrel does better than aspirin as was shown by the CAPRIE data (4) but the drug is more expensive.
The HOPE trial (5) has shown that ACE inhibition with ramipril improves long term prognosis especially in PAD patients.
The Heart Protection Study (HPS) (6) clearly demonstrated that statins can decrease total cardiovascular risk even beyond cholesterol decrease.
Thus, many arguments are available that triple therapy with antiplatelet drugs, ACE inhibitors and statins should be administered to PAD patients. Such obviously opens the discussion on compliance and costs. However, costs linked to complications such as stroke, are very elevated as well. Elaborated calculations should be made to examine the balance between the costs of treatment and the cost of prevention.

In this respect, symptomatic treatment of intermittent claudication should not be forgotten. Most effective is exercise training, especially when given at regular intervals in supervised conditions. Nicotine abuse should be stopped. TASC II clarified the objective value of two drugs (cilostazol, naftidrofuryl) that can cause a certain degree of symptomatic relief (class 1 recommendation).

The content of this article reflects the personal opinion of the author/s and is not necessarily the official position of the European Society of Cardiology.

Conclusion:

The transatlantic consensus document TASCII has clearly focused physician's attention toward the severely increased risk of peripheral artery disease (PAD). Recent data have called it an "angina pectoris equivalent ". Thus, all attention should be given to the detection and treatment of PAD patients. For detection, ankle brachial artery pressure index measurements (ABI) are extremely helpful. To decrease risk, life style adaptation is essential; combination of antiplatelet drugs, ACE inhibitors and statins are recommended to help reaching this important goal.