Comparison of exercise performance in left main and three-vessel coronary artery disease

Percutaneous intervention of unprotected left main coronary artery

Successful percutaneous intervention of unprotected left main coronary artery (LMCA) in lieu of surgical revascularization represents the next wave of challenges that the field of interventional cardiology will try to overcome. Significant LMCA stenosis, commonly secondary to atherosclerosis, is seen in about 4-10% of cases presenting to the cardiac catheterization laboratory. Currently, the vast majority of these patients undergo surgical revascularization unless there are prohibitive reasons for surgical revascularization. Several challenges of percutaneous revascularization have been overcome with stents, intravascular brachytherapy, and other technical improvements. Yet, several remaining limitations of percutaneous intervention, such as in-stent restenosis, have to be improved further before randomized clinical trials of surgical and percutaneous revascularization of unprotected LMCA disease can be contemplated to establish a new standard of care.

Value of fractional flow reserve in making decisions about bypass surgery for equivocal left main coronary artery disease

OBJECTIVE

To investigate the value of coronary pressure derived fractional flow reserve (FFR) measurements in supporting decisions about medical or surgical treatment in patients with angiographically equivocal left main coronary artery stenosis.

DESIGN

A two centre prospective single cohort follow up study.

INTERVENTIONS

FFR of the left main coronary artery was determined in 54 consecutive patients with angiographically equivocal left main coronary artery disease. If FFR was >/= 0.75, medical treatment was chosen; if FFR was < 0.75, surgical treatment was chosen.

MAIN OUTCOME MEASURES

Freedom from death, myocardial infarction, or any coronary revascularisation procedure.

RESULTS

In 24 patients (44%), FFR was >/= 0.75 and medical treatment was chosen (medical group). In the remaining 30 patients (56%), FFR was < 0.75 and bypass surgery was performed (surgical group). Mean (SD) follow up was 29 (15) months (range 12-65 months). Survival among patients at three years of follow up was 100% in the medical group and 97% in the surgical group. Event-free survival was 76% in the medical group and 83% in the surgical group.

CONCLUSIONS

FFR supports decision making in equivocal left main coronary artery disease. If FFR is below 0.75, the decision for bypass surgery is supported. If FFR is above 0.75, a conservative approach is justified.

Cardiac catheter complications related to left main stem disease

OBJECTIVE

To examine the incidence and outcome of cardiac catheter complications related to left main coronary artery disease or damage using the CECCC (Confidential Enquiry into Cardiac Catheter Complications) database.

SETTING

Coordinating centre for national database.

DESIGN

Retrospective analysis of reports to a national multicentre database for cardiac catheter complications. Complications involving the left main coronary artery were flagged at entry. Where necessary additional information was sought from participating centres. 112,921 procedures were registered, 12,849 of which were coronary angioplasties and the remainder diagnostic studies.

RESULTS

The total number of cases for which complications were recorded was 993 (0.88%). In 61 (6.14%) of the 993 cases complications were associated with left main coronary disease or damage. In 57 (93%) of these 61 cases complications were major, necessitating resuscitation or immediate coronary bypass grafting. Ten patients (16%) died in the catheter laboratory, a further 9 (15%) within 24 hours, and a total of 23 patients (38%) died within one month of the procedure. Left main stem related complications account for 17% of total mortality in the CECCC database. Urgent coronary bypass grafting was attempted in 42 patients, of whom 31 were alive at one month. In all of the six reported PTCA-related complications the cause was traumatic damage to the left main coronary artery. Operators of all grades of seniority experienced complications in similar proportions.

CONCLUSIONS

The risk of a complication relating to the left main stem is relatively low, but when such complications occur they tend to be life-threatening and contribute a fifth of total catheter-related mortality. In the absence of a widely available non-invasive investigation with good predictive value for left main stem disease, the best safeguard is careful technique. Patients who do develop complications should have emergency coronary bypass grafting.

Left main coronary artery disease: assessment, diagnosis, and therapy

This article reviews and updates the current literature concerning the assessment, diagnosis, and therapy of coronary disease involving the LMCA. Included is recent information regarding the natural history, congenital abnormalities, noninvasive diagnostic studies, and role of coronary bypass surgery and percutaneous coronary interventions in treating disease of the LMCA. At present, it remains that the LMCA is a difficult segment to assess angiographically. The use of noninvasive imaging does not specifically distinguish LMCA from other types of coronary disease. Coronary bypass surgery has a proven benefit in the treatment of disease of the LMCA. Currently, interventional procedures are limited by significant risks, and surgical treatment with coronary bypass surgery remains the therapy of choice.