Primary angioplasty for STEMI

Primary angioplasty for STEMI

Primary angioplasty is the best method for reperfusion of an occluded coronary artery in ST elevation myocardial infarction (STEMI). It produces better outcomes at 30 days and 1 year after the procedure with lower death rates as well as lower rates of reinfarction and stroke. The only limitation is the higher cost and the lower availability to the general population. Even when the delay between angioplasty and potential thrombolysis is upto one hour in a given setting, angioplasty gives better results than thrombolysis. The aim of any primary angioplasty program should be to have the shortest door-balloon time (time from hospital entry to the first balloon dilation in the culprit vessel). Strategies of initial thrombolysis followed by ischemia driven as well as routine angioplasties are also being evaluated with good success.

In primary angioplasty the first concern is to re-establish flow to the occluded artery (culprit vessel) at the earliest. This is achieved by rapidly establishing an arterial access, usually by the femoral route and taking quick shots of diagnostic angiography followed by rapid sequence angioplasty. It is usual to use a diagnostic catheter for the non-infarct territory to start with followed by direct cannulation with guide catheter for the infarct related artery to save time. As soon as the necessary diagnostic angiograms are obtained, the lesion is crossed with a guide wire and predilated. Use of a thrombus aspiration catheter to reduce the thrombus load during primary angioplasty is becoming popular  after the recent trials reporting favourable outcome. Angioplasty is usually restricted to the culprit vessel except in cases of cardiogenic shock where the motto is as complete a revascularization as possible. Many operators may use bare metal stents during primary angioplasty, though there is no strong point against them. Post dilatation of the stent may not be ideal in the setting of primary angioplasty with high thrombus load for fear of distal embolisation and occurrence of no-reflow / slow reflow phenomenon. Adjuvant therapy with glycoprotein IIb/IIIa inhibitors is routine with primary angioplasty. Intra aortic balloon support is useful in a compromised patient being taken up for primary angioplasty.