Ultrasound targets angioplasty

Sep 6 2006

World Congress of Cardiology 2006 - A simple technique - combining cardiac ultrasound with a heart muscle-stimulating drug - can identify the MI patients who would benefit most from angioplasty after thrombolysis, reports a study in Hot Line session II.

On the basis of the results, presenter Gerrit Veen (Amsterdam, Holland) called for testing to be introduced as standard clinical practice following myocardial infarction (MI).

The new method reported in the VIAMI (viability-guided angioplasty after acute myocardial infarction) study, involved the administration of the heart stimulant drug (dobutamine) during echocardiograms to identify patients in whom remaining viable heart muscle was present in the area of MI.

Observations suggest that patients with a viable area of heart muscle in the infracted area are at higher risk of suffering a second heart attack, compared to those without viable muscle.

In the study, the 216 patients with viable heart muscle were randomised to receive either angioplasty or conservative treatment. In the first group, angioplasty was performed as soon as possible, while in the second group it was only performed in case of threatening new signs and symptoms.

Results at six months show that only 6.6 % of patients in the angioplasty group developed problems, compared to 15.5 % of patients in the conservatively managed group (P<0.001).

Patients without residual viable heart muscle were at low risk of a second heart attack in VIAMI. This group had an eventfree survival of 94.7% compared with 85.5% in the viable tissue group (p<0.05).

“Thus the strategy of routinely performing angioplasty in all heart attack patients after clot-lysing therapy doesn’t seem warranted,” said Veen.

Also on the theme of angioplasty in Hot Line session II, data from RIVIERA (Registry on IV anticoagulation in elective and primary real world of angioplasty) was presented. The study reviewed intravenous anticoagulation in angioplasty and identified modifiable factors associated with an increased risk of major complications.

The RIVIERA registry included 7,962 consecutive angioplasty patients who had been enrolled for elective or primary percutaneous coronary intervention (PCI) in 144 hospitals across 23 countries in Europe, Africa, South America and Asia.

The aim was to provide a global picture of angiography. Registry results reveaedl hospital deaths of 0.3 %, MI rates of 1.0 %, major bleeding rates of 0.3% and minor bleeding, of 3.1%.

Gilles Montalescot (Paris, France) said mortality and major bleeds were lower than usually reported. In addition, use of statins, thienopyridine pre-treatment and enoxaparin resulted in fewer ischaemic events, while use of GPIIb/IIIa inhibitors, UFH and enoxaparin led to more bleeding.

Furthermore, radial as opposed to femoral access led to less bleeding and fewer ischemic events.

Montalescot: “It’s good news because the study shows that many of the risk factors are modifiable, suggesting that improvements can be made to clinical outcomes.”

Finally, six month data from a phase II clinical evaluation of the XIENCE V everolimus-eluting coronary stent (SPIRIT II study), was presented by Patrick Serruys (Rotterdam, the Netherlands). It showed that in-stent late loss was superior for the new everolimus-eluting stent, compared with the established sirolimus stent.

Results show that luminal late loss (the difference in diameter from postangioplasty to time of re-study) was 0.11 mm for the everolimus-eluting stent, compared to 0.36 mm for the sirolimus stent (p=0.0001).

However, Salim Yusuf (McMaster University, Canada ) commented: “I don’t know whether the everolimus stent offers an advantage or not because this study is not dealing with a clinically-relevant end point.”