Proximal Left Anterior Descending Lesion Research Articles

Randomized Comparison of Minimally Invasive Direct Coronary Artery Bypass Surgery Versus Sirolimus-Eluting Stenting in Isolated Proximal Left Anterior Descending Coronary Artery Stenosis

The purpose of this randomized study was to compare sirolimus-eluting stenting (SES) with minimally invasive direct coronary artery bypass (MIDCAB) surgery for patients with isolated proximal left anterior descending (LAD) coronary artery disease. Bare-metal stenting is inferior to MIDCAB surgery in patients with isolated proximal LAD lesions due to a higher reintervention rate with similar results for mortality and reinfarction. SES are effective in restenosis reduction. A total of 130 patients with significant proximal LAD coronary artery disease were randomized to either SES (n = 65) or MIDCAB surgery (n = 65). The primary clinical end point was noninferiority in freedom from major adverse cardiac events (MACE), such as cardiac death, myocardial infarction, and the need for target vessel revascularization within 12 months. Follow-up was completed for all patients. MACE occurred in 7.7% of patients after stenting, as compared with 7.7% after surgery (p = 0.03 for noninferiority). The individual components of the combined end point revealed mixed results. Although noninferiority was revealed for the difference in death and myocardial infarction (1.5% vs. 7.7%, noninferiority p < 0.001), noninferiority was not established for the difference in target vessel revascularization (6.2% vs. 0%, noninferiority p = 0.21). Clinical symptoms improved significantly in both treatment groups in comparison with baseline, and the percentage of patients free from angina after 12 months was 81% versus 74% (p = 0.49). In isolated proximal LAD disease, SES is noninferior to MIDCAB surgery at 12-month follow-up with respect to MACE at a similar relief in clinical symptoms.

Percutaneous coronary intervention with drug-eluting stent implantation vs. minimally invasive direct coronary artery bypass (MIDCAB) in patients with left anterior descending coronary artery stenosis

The aim of this study was to assess the effects of percutaneous coronary intervention with drug-eluting stents (DESs) versus minimally invasive direct coronary artery bypass (MIDCAB) surgery in the management of patients with proximal left anterior descending (LAD) coronary artery stenosis. Until recent years, despite the advantages of percutaneous transluminal coronary angioplasty (PTCA) with bare metal stent implantation, such as shorter hospital stays and recovery time, MIDCAB showed better results with regard to the need for repeated intervention in the target vessel than PTCA with proximal LAD lesions. Symptomatic patients (n = 189) were randomly assigned to DES group (n = 119) and MIDCAB group (n = 70). Patients with an isolated high-grade lesion (stenosis of > or = 70% of the luminal diameter) in the proximal LAD coronary artery (from the ostium to the first diagonal branch) were included in this study. During the 6-month follow-up period, 1.7% (n = 2) in the DES group needed repeated revascularization procedures for target lesion revascularization compared with 5.9% (n = 4) in the MIDCAB group (P = 0.196). The rates of death and myocardial infarction were similar in both groups [DES 0.0% (n = 0) vs. MIDCAB 2.9% (n = 2), P = 0.135; DES 1.7% (n = 2) vs. MIDCAB 2.9% (n = 2), P = 0.627; respectively] during 6 months of follow-up. In-hospital length of stay was significantly shorter in the DES group compared with the MIDCAB group (5.8 +/- 2.1 days vs. 8.9 +/- 2.6 days; P = 0.001). DES implantation and MIDCAB surgery showed similar rates of myocardial infarction, the need for repeated revascularization, and death during 6 months of follow-up. However, DES implantation resulted in lower average number of hospital stays and similar postoperative complications.

Intracoronary ST-T alternans during coronary balloon angioplasty.

To evaluate the presence and clinical significance of electrical alternans during PTCA, intracoronary electrocardiography (ic-ECG) was performed in 65 consecutive lesions. ST-T alternans, defined as a beat-to-beat difference in the ST elevation > or = 1 mm, was present in five lesions (7.7%), all in the proximal left anterior descending (LAD) coronary artery. The phenomenon was seen only after 130 sec (mean 174 +/- 57) of balloon inflation. Only two of the five showed ST-T alternans simultaneously on both surface and ic-ECG. One of five patients had premature ventricular contractions following ST-T alternans. Three of these five lesions required a second balloon inflation with duration of > or = 300 sec; there was no ST-T alternans on the second inflation in any of these lesions. We conclude: (1) the detection of ST-T alternans during PTCA is enhanced by use of ic-ECG, (2) electrical alternans during PTCA was seen only in proximal LAD lesions, implicating a large amount of ischemic myocardium as a requisite for the phenomenon, (3) electrical alternans is not immediate, requiring a certain duration of balloon occlusion and hence ischemia to occur, and (4) the absence of ST-T alternans during second balloon inflations suggests ischemic preconditioning may abolish this phenomenon.

Gianturco‐Roubin stent placement for variant angina refractory to medical treatment

A 43-yr-old man with mild, fixed obstruction of the left anterior descending (LAD) coronary artery and severe, uncontrolled variant angina underwent placement of an endovascular stent to preserve patency of the artery. The decision for stent placement was based on several factors, including refractoriness to medical treatment and standard balloon angioplasty, documented spasm localized to the proximal LAD lesion, and the morbidity, mortality, and costs associated with the surgical approach in this type of patient. At follow-up, there was moderate restenosis of the stented coronary segment; the vasospastic angina syndrome had totally resolved.

Interventricular septal motion in acute myocardial infarction with proximal and distal left anterior descending coronary lesions

To evaluate the ability of echocardiography to detect and localize lesions of the proximal and distal left anterior descending (LAD) coronary arteries, the systolic excursion of the left side of the septum and the ratio of septal to posterior wall excursion (IVS/PW) were measured in 26 patients with acute myocardial infarction (AMI) and nine normal control subjects. The patients with proximal LAD lesions had septal wall excursions of less than 3 mm, whereas in those with distal LAD lesions septal wall excursions were more than 3 mm. All patients with proximal LAD lesions showed an IVS/PW ratio of less than 0.4, but in those with distal LAD lesions the ratio was 0.4 or greater. We conclude that reduced or absent interventicular septal motion in anterior AMI suggests an LAD lesion, and a septal excursion of less than 3 mm suggests involvement of the proximal LAD artery, whereas septal excursion of 3 mm or more indicates involvement of the distal LAD artery.

Natural history of left anterior descending coronary artery obstruction: significance of location of stenoses in medically treated patients.

We examined the prognostic significance of an obstructive lesion in the proximal left anterior descending (LAD) coronary artery. Five-year or longer follow-up data were examined from 311 patients with greater than 70% obstruction of the LAD treated without surgery. Mortality was compared in subsets with lesions proximal to and distal to the first septal perforating artery. Survival curves were worse in patients with proximal than with distal LAD disease (p less than 0.05); lesion location remained a significant determinant of survival when ejection fraction, age, and sex were controlled using a Cox regression model. However, when patient subsets were examined, survival with proximal LAD disease was worse than with distal obstruction only in the presence of an associated right coronary artery lesion and an ejection fraction of less than 40% (p less than 0.01). Patients with proximal LAD plus right coronary lesions had a 5-year mortality rate (34.08 +/- 8.9%) that was not significantly (p greater than 0.05) different from that of a group of 66 patients with greater than 50% narrowing of the left main coronary artery (24.02 +/- 4.3%). Thus, proximal LAD disease is more significant than is a distal lesion only in the presence of right coronary obstruction. This two-vessel combination results in a mortality rate as high as that associated with left main coronary artery obstruction.

Proximal left anterior descending coronary heart disease and complex ventricular arrhythmias.

In this study, 87 consecutive patients with angiographically proven coronary artery disease (CAD, stenosis greater than 75%) underwent 24-h Holter monitoring, 76 of them having had transmural myocardial infarction, a mean of five months before evaluation. Of the total, 51 patients showed single-vessel disease, in 31 (61%) of them with involvement of the left anterior descending (LAD) artery. In 26 patients with proximal LAD stenosis or occlusion and usually large aneurysms and subsequently impaired left ventricular function relatively low prevalence of significant ventricular premature contraction (VPC, Lown greater than or equal to III) was seen. On the contrary in 19 patients with multivessel disease and proximal LAD stenosis advanced forms of VPCs were present in 63% (p less than 0.01). Further both groups differed significantly in the frequency of postinfarction angina (30% vs. 100%; p less than 0.001) and their incidence in positive exercise stress tests (15% vs. 84%; p less than 0.001). Ejection fractions were comparable in both groups (mean 45% vs. 52%). Finally 17 patients with multivessel disease but without proximal LAD lesion did not differ in any of the above mentioned parameters, when compared to the patients with single-vessel disease and proximal LAD stenosis. We conclude that impaired left ventricular function does not sufficiently explain the high risk of sudden death in postmyocardial infarction patients. The coronary and functional status of the surviving myocardium has to be taken into consideration as well.