Prospective observational study of primary angioplasty of the infarct-related artery for acute myocardial infarction.

Primary angioplasty has been shown to reduce rates of in-hospital mortality, recurrent ischaemia and infarction. However, the role of primary stenting and abciximab is presently undergoing evaluation. This study attempted to examine the feasibility, safety and outcomes of primary angioplasty in the treatment of acute myocardial infarction. Data in 100 patients who underwent primary angioplasty for evolving acute myocardial infarction was prospectively analysed to assess the safety and efficacy of various modalities. Twenty patients were in Killip class III and above. Multivessel (2 or more vessels) disease was noted in more than 52 cases. Procedural success was 99 percent; 86 patients received primary stenting, majority of them had Kalam-Raju stent implantation. Adjunct treatment included abciximab infusion in 22 and intra-aortic balloon pump support in 12. Overall mortality rate was six percent with a mortality of 2.2 percent in non-cardiogenic shock patients. Recurrent ischaemic events were noted in five, three of them had successful reperfusion with repeat angioplasty. None of the patients had emergency coronary artery bypass surgery. It is concluded that primary angioplasty is safe and effective with high procedural success. Recurrent ischaemic events are low, possibly due to routine use of stenting and selective use of abciximab.

Clinical evaluation of new balloon mountable coil stent: in-hospital and follow-up results.

The purpose of this study was to determine the feasibility, safety and efficacy of elective deployment of a new coil-stent (KR stent) in patients with coronary artery disease. KR stent deployment was attempted in 100 patients (135 lesions) enrolled prospectively at a single centre from December 1996 to March 1997. Ten, 15, 18, 24, and 32 mm long KR stents were manually crimped onto balloons and deployed in native coronary artery lesions. Majority of the patients had recent acute coronary syndromes (unstable angina 30% and post-myocardial infarction angina 56%). Diabetes was present in 34 percent of the patients. Fifty-six percent had single-vessel and 44 percent multi-vessel disease. In 38 percent, the lesions were located in proximal segments and 40 percent of lesions were long. KR stents were successfully deployed in 98 percent of patients. Mean minimal luminal diameter increased by 2.89 +/- 0.63 mm (from 0.57 +/- 0.38 mm before to 3.45 +/- 0.56 mm after the procedure). Mean percent diameter stenosis decreased from 83.33 +/- 10.84 percent before to 3.38 +/- 5.74 percent after the stent deployment. Mean reference vessel diameter was 3.45 +/- 0.56 mm. There were occasional technical complications including balloon rupture (1), stent migration (2) and distal embolisation of atheromatous material (1). One patient developed subacute stent thrombosis. There were no other major in-hospital cardiovascular events. At the end of six-month follow-up, there were no myocardial infarction or death. Six patients presented with recurrence of symptoms within six-months of the procedure, four of whom underwent target vessel revascularisation procedure. In conclusion, the in-hospital and six-month follow-up clinical results were highly encouraging with KR stent. Successful deployment rates were high despite unfavourable clinical and angiographic background. Low clinical events on follow-up will make it suitable for elective stenting.

Thrombolysis in left-sided prosthetic valve occlusion: immediate and follow-up results.

Thrombolytic therapy is used increasingly for prosthetic valve thrombosis. Fear of peripheral embolism has limited its use in left-sided valve occlusions. Thirty-eight patients with prosthetic valve occlusion were treated with thrombolytic agents on 44 occasions. Duration of thrombolytic therapy was individualized. Patients were followed up with clinical, echocardiographic, and cine-fluoroscopic evaluation. Average time from onset of symptoms to presentation was 9.7 days. The anticoagulation status was inadequate in 70% of instances. The majority (75%) were in functional class IV, 8 of them being in shock. Overall success was seen in 88.6%: immediate complete success in 18 and partial in 21. Nine of those with partial success had delayed opening of the leaflets. There were nine instances of rethrombosis and one instance of re-rethrombosis; 6 patients received repeat thrombolysis with success in 5. Seventy-six percent (29/38) of the patients were surviving at the time of reporting. In conclusion, the present study demonstrates the feasibility of thrombolytic therapy for left-sided prosthetic valve occlusion. Delayed opening is common in patients with initial partial success. Rethrombosis remains a major problem.