Emergency coronary stenting for acute occlusive dissection of the left main coronary artery

Clinical Outcomes and Angiographic Results of Bailout Stenting for Guide Catheter-Induced Iatrogenic Coronary Artery Dissection - Impact of Stent Type

BACKGROUND

Guide catheter-induced iatrogenic coronary artery dissection is a rare but feared complication. When it occurs, bailout stenting is widely performed; however, its prognosis and the impact of stent type remains unclear.Methods and Results:The study population consisted of 77,257 consecutive patients (coronary angiography, 55,864; percutaneous coronary intervention, 21,393) between 2000 and 2015. We investigated the incidence, clinical outcomes, and angiographic results after bailout stenting and compared by stent type: bare-metal stent (BMS) and drug-eluting stent (DES). Iatrogenic coronary artery dissection occurred in 105 patients (incidence rate, 0.14%). All cases of iatrogenic coronary artery dissection that were recognized as requiring bailout procedure could be managed by stent implantation, and no patients died during bailout procedure. The 5-year cumulative incidences of cardiac death, target lesion revascularization, and major adverse cardiac events were 11.3%, 10.3%, and 21.0%, respectively. The binary restenosis rate was 10.4%, and it was not significantly different between BMS and DES implantation. In lesions with preprocedural stenosis, however, it was significantly lower in the DES group than in the BMS group. On the other hand, coronary artery dissection recurred in 8 patients, which was observed only after DES implantation.

CONCLUSIONS

The immediate and long-term outcomes of bailout stenting for iatrogenic coronary artery dissection were acceptable. Although DES may be favorable for stenotic lesions, coronary artery dissection can recur after DES implantation.

Iatrogenic right coronary artery dissection caused by diagnostic transradial cardiac catheterization

We are presenting rare, but life‐threatening complication of diagnostic coronary catheterization. To overcome the problem requires operator's experience and appropriate actions. We want to share our experience to interventionalists to be aware and ready to recognize and overcome such complication.

Iatrogenic left main coronary artery dissection

We present a case of iatrogenic left main coronary artery dissection, successfully treated by prompt bail-out stenting, and provide a brief discussion on its occurrence and treatment, as well as the immediate and long-term outcome of percutaneous coronary intervention, including our own single-centre experience, for this potentially catastrophic complication.

Significant left main coronary artery disease from iatrogenic dissection during coronary angiography

Though atherosclerotic obstruction is the major cause of the obstructive left main coronary artery (LMCA) disease, it can be associated with iatrogenic dissection during coronary angiography. Here we report a case with severe LMCA stenosis due to catheter induced dissection in a 77-year-old man which was detected 9 months later. By careful review of the angiogram had taken at 9 months ago, the LMCA was injured by the diagnostic left Judkin's catheter during the first coronary angiography. The initial lesion was neglected and the dissection got worse with time. The patient was successfully treated with two drug-eluting stents by crushing technique and discharged without further complication.

Iatrogenic right coronary artery dissection distal to a total occlusion: a case report

Introduction

Coronary artery dissections with or without rupture is a rare but well-recognized complication of coronary angiography with a high morbidity and mortality rate.

Case presentation

We present a rare case of right coronary artery dissection distal to a totally occluded vessel. The vessel dissected during the second injection of contrast agent without any direct mechanical manipulation (catheter or guide-wire induced). Hopefully the dissection had no clinical consequences and the patient was discharged after 48 hour intensive monitoring.

Conclusions

We believe that the contrast agent that was forced in the proximal part of the RCA increased through the anastomotic branches the sheer stress on the diseased endothelium of the distal artery causing it to dissect. It is an instructive -not previously described- phenomenon that underscores that atherosclerotic tissue is unpredictable and should be treated with extreme caution.

Clinical and angiographic results of angioplasty with a paclitaxel-eluting stent for unprotected left main coronary artery disease (a study of 101 consecutive patients)

BACKGROUND

After coronary stenting with drug eluting stents, long-term clinical outcome of unprotected left main coronary artery disease is unknown, even large scale registries or randomised trials with coronary artery bypass graft are ongoing.

AIMS

To report clinical and angiographic results of paclitaxel-eluting stent implantation for left main coronary artery stenosis (a series of 101 consecutive patients).

METHODS

This report is a prospective study performed to evaluate the immediate and mid-term clinical and angiographic outcomes of patients undergoing paclitaxel-eluting stent (PES) implantation for unprotected left main coronary artery (LMCA) stenosis. From January 2004 to December 2005, 101 consecutive patients were stented with paclitaxel-eluting stents (the provisional T stenting technique followed by Kissing balloon for distal left main vessel disease).

RESULTS

Mean age was 68.9+/-11.07 years. 73.3% of patients were male. Acute coronary syndrome was present in 65% of patients, of whom 22.8% had ST elevation. Distal left main trunk lesions were present in 87.1% of cases. Three-vessel disease represented 7% of cases. Angiographic success was obtained in 97.03% of patients with an acute gain of 2.18+/-0.53mm. GpIIbIIIa inhibitors were used in only 8.9% of cases. Hospital stay was 7.6 +/- 3.7 days. In-hospital complications were present in 7.9%, with a hospital mortality rate of 2%. At six month follow-up, the rate of target lesion revascularization (TLR) was 3%, and the rate for major adverse cardiac events (MACE) was 8.9%. Angiographic control was performed in 88.1% and a late loss of 0.1mm (0.04-0.2mm) was noted. Re-stenosis occurred in 4 patients (4.5% of cases). 4 patients (4%) died, including 2 from cardiac causes.

CONCLUSION

Paclitaxel-eluting stent implantation for unprotected left main coronary disease appears to be safe with high procedural success rate and a low re-stenosis rate at six month-follow-up.

Catheter-Induced Left Main Coronary Artery Spiral Dissection: Stenting or Bypass? (Case Report and Literature Review)

Catheter-induced Left Main Coronary Artery (LMCA) dissection is a very uncommon but life-threatening complication of coronary intervention and requires urgent management. We report one such patient whose risk factors appear to be Coronary Artery Disease (CAD), smoking and a prior Myocardial Infarction (MI).

Left main coronary artery stenosis: state-of-the-art

Patients with stenosis of the left main coronary artery present difficult challenges. The risks associated with this lesion have been known since the early days of angiography when patients were found to have increased mortality during follow-up. This information led to the general guidelines that surgical revascularization should be considered the treatment of choice in patients with significant left main coronary artery stenosis. Current advances in invasive cardiology have brought important information to the field. Intravascular ultrasound is now used routinely to evaluate angiographically indeterminate lesions with criteria now set forward as to what constitutes an indication for revascularization. Stents have even further dramatically changed the landscape. There are substantial issues, however, that need to addressed. These include the following: (1) the effect of specific lesion location on outcome - it is known that patients with distal bifurcation left main disease have worse outcome; (2) the potential for subacute thrombosis of the left main coronary artery; (3) the impact of left ventricular function and patient comorbidities irrespective of the degree and location of left main coronary artery stenosis; and (4) the risk-benefit ratio of stenting versus coronary artery bypass graft surgery. These issues are currently being addressed in two seminally important trials including the SYNTAX trial, which randomizes patients with left main and/or three-vessel disease to either coronary artery bypass graft surgery or a TAXUS drug-eluting stent. This trial is in the final stages of patient recruitment and will have important implications for the field. The other trial is the COMBAT trial, which is focused exclusively on left main coronary artery stenosis and randomizes patients with left main coronary artery disease either to a Sirolimus-eluting stent (Cypher, Johnson and Johnson Cordis, USA) or to coronary artery bypass graft surgery. The field of left main coronary artery disease continues to expand in terms of the evidence available for optimal patient evaluation and selection of treatment modalities.

Percutaneous coronary intervention for iatrogenic left main coronary artery dissection

BACKGROUND

Although catheter-induced left main coronary artery (LMCA) dissection is a rare complication of coronary catheterization, it is a common cause of periprocedural mortality. Emergent coronary artery bypass surgery (CABG) is the mainstay for managing this acute complication. However, hemodynamic deterioration may progress while patients await emergent CABG; consequently, a high postoperative mortality rate has been reported. Although the number of cases was small, prompt bail-out stenting for iatrogenic LMCA dissection had reportedly reversed this complication with favorable clinical outcomes.

METHODS

This study included 13 cases of attempted stenting for iatrogenic LMCA dissection classified as grades C-F based on the National Heart, Lung and Blood Institute (NHLBI) classification system. Angiographic success, in-hospital mortality and long-term outcomes were analyzed.

RESULTS

The incidence of iatrogenic LM dissection was 0.071%. Most of the patients were initially asymptomatic. Angiographic success was achieved in 11 of 13 patients (84.6%). Including one patient who underwent emergent CABG after a failed wiring attempt, two mortalities occurred in this series. Mean follow-up duration of the ten patients discharged was 30.1+/-11.8 months, and no cardiac deaths occurred. Follow-up angiogram of eight patients with a mean interval of 5.2+/-2.3 months after initial event demonstrated restenosis in three patients occurring either at the ostiums of the left anterior descending artery or left circumflex artery. Revascularization was performed on two patients.

CONCLUSIONS

Successful bail-out stenting resulted in good long-term survival and should be considered for initial management of iatrogenic LMCA dissection.

[Left main coronary artery angioplasty: report of five cases illustrating the current indications]

OBJECTIVES

The purpose of our study is to illustrate by five original observations the various situations where the stenting of the left main coronary artery can be proposed in alternative to aortocoronary bridging with encouraging results in short- and long-term.

MATERIALS AND METHODS

We report a retrospective study relating to five cases with left main disease treated by stenting between 1996 and 2002 at our institution. In two cases the left main stem was unprotected. In two other cases, the left main trunk was protected. And the last case was an emergency stenting for an iatrogenic dissection of the left main coronary artery.

RESULTS

The stenting was carried out successfully among the five patients without major in-hospital complication. During the follow-up of 29 months at mean, no death was deplored, and no target lesion revascularization was required on the left main coronary artery (with a left main trunk permeable on three coronarographic controls).

CONCLUSIONS

In the light of these results, and basing on the published data, we conclude that stenting for the left main coronary disease may be a safe and effective alternative to coronary artery bypass surgery in particular cases among "selected" patients (refusal or surgical contraindication, protected left main coronary artery, spontaneous or iatrogenic acute occlusion of the left main coronary artery).

Bail-out stenting for left main coronary artery dissection during catheter-based procedure: acute and long-term results

BACKGROUND

The optimal treatment of patients with left main coronary artery (LMCA) dissection during catheter-based procedure remains uncertain.

HYPOTHESIS

In cases with significant LMCA dissection occurring during catheter-based procedure, prompt stent implantation may be safe and associated with favorable clinical outcome.

METHODS

We evaluated the acute and long-term results of bail-out stenting for LMCA dissection occurring during a catheter-based procedure in 10 patients.

RESULTS

Initially, there was no significant stenosis of LMCA segments in these patients. Catheter-induced dissection occurred in eight patients (during diagnostic angiography in three patients and during guiding catheter manipulation in five patients). Two patients suffered dissection in the setting of stent deployment in other vessels. Therefore, bail-out stenting for LMCA dissection was performed in a total of 10 patients. In four patients, hypotension developed and an intra-aortic balloon pump was placed during the procedure. Stents were successfully deployed in all patients; there was no in-hospital mortality. Six-month angiographic follow-up was performed in eight patients. No angiographic restenosis (diameter stenosis > or = 50%) was observed in any patient at follow-up study. During a mean follow-up of 31 +/- 25 months after hospital discharge, there was no major adverse cardiac event (death, myocardial infarction, and target lesion revascularization).

CONCLUSIONS

Bail-out LMCA stenting is technically feasible and showed good acute and long-term results in a small series of patients.

Left main artery dissection during 4 French coronary angiography in elderly patient with severe aortic stenosis: "speedy recovery" using emergency primary stenting

A 70-year-old woman was referred due to a symptomatic severe calcific aortic stenosis. An iatrogenic dissection of the left main artery with total occlusion and arrest (asystole) occurred during preoperative 4Fr coronography. "Speedy recovery" is achieved with a strategy of percutaneous primary stenting revascularization combined with cardiopulmonary maneuvers.

Elective stenting of unprotected left main coronary artery stenosis: effect of debulking before stenting and intravascular ultrasound guidance

OBJECTIVES

We sought to evaluate: 1) the long-term outcomes of 127 selected patients receiving unprotected left main coronary artery (LMCA) stenting; and 2) the impact of the debulking procedure before stenting and intravascular ultrasound (IVUS) guidance on their clinical outcomes.

BACKGROUND

The long-term safety of stenting of unprotected LMCA stenoses has not been established yet.

METHODS

A total of 127 consecutive patients with unprotected LMCA stenosis and normal left ventricular function were treated by elective stenting. The long-term outcomes were evaluated between two groups: IVUS guidance (n = 77) vs. angiographic guidance (n = 50); and debulking plus stenting (debulking/stenting; n = 40) vs. stenting only (n = 87).

RESULTS

Angiographic restenosis was documented in 19 (19%) of 100 patients. The lumen diameter after stenting was significantly larger in IVUS-guided group (p = 0.003). The angiographic restenosis rate was significantly lower in the debulking/stenting group (8.3% vs. 25%, p = 0.034). The reference artery size was the only independent predictor of angiographic restenosis. During follow-up (25.5 +/- 16.7 months), there were four deaths, but no nonfatal myocardial infarctions occurred. The survival rate was 97.0 +/- 1.7% at two years.

CONCLUSIONS

These data suggest that stenting of unprotected LMCA stenosis might be associated with a favorable long-term outcome in selected patients. Guidance with IVUS may optimize the immediate results, and debulking before stenting seems to be effective in reducing the restenosis rate. However, we need a large-scale, randomized study.

Unprotected left main coronary artery stenting: correlates of midterm survival and impact of patient selection

BACKGROUND

The study served to present the in-hospital and six-month clinical outcome and also the long-term survival data of a consecutive series of patients undergoing stenting for unprotected left main coronary artery (LMCA) disease.

METHODS

Revascularization with coronary bypass surgery has been generally recommended for treatment of left main coronary stenosis. Improvements in angioplasty and coronary stent techniques and equipment may result in the wider applicability of a percutaneous approach. A total of 92 consecutive patients underwent unprotected LMCA stenting between March 1994 and December 1998. For the initial 39 patients (group I) angioplasty was performed only when surgical revascularization was contraindicated. The remaining 53 patients (group II) also included patients in whom surgery was feasible. Patients were followed for 7.3 +/- 5.8 months (median 239 days; range 49 to 1,477 days).

RESULTS

Compared to group I, group II patients had higher left ventricular ejection fraction (60 +/- 12% vs. 51 +/- 16%, p < 0.01), less severe LMCA stenosis (68 +/- 12% vs. 80 +/- 10%, p < 0.001), lower surgical risk score (13 +/- 7 vs. 20 +/- 7, p < 0.001), and had angioplasty more often performed via the radial approach (88% vs. 23%, p < 0.001) with smaller guiding catheters (6F: 49% vs. 15%; 8F: 2% vs. 77%, p < 0.001). The procedural success rate was 100%. In-hospital mortality was 4% (4 deaths, 3 cardiac). During follow-up there were six deaths, 13 patients required repeat percutaneous transluminal coronary angioplasty (4 LMCA), and two required coronary artery bypass graft surgery. Estimated survival (+/- SEE) was 89 +/- 6.3% at 500 days and 85 +/- 12% at 1,000 days post-stenting. Overall mortality was 3.8% in group II and 20.5% in group I (p < 0.02).

CONCLUSIONS

Coronary stenting can be performed safely in high-risk individuals with acceptable intermediate-term outcome. It may be feasible to broaden the application of this technique in selected patients needing revascularization for left main coronary disease.

Factors predicting mortality in patients after myocardial infarction caused by left main coronary artery occlusion: significance of ST segment elevation in both aVR and aVL leads

Acute left main coronary artery obstruction is rare and most patients in this clinical setting die of sudden death or cardiogenic shock. During the past 8 years, we encountered 13 patients with acute myocardial infarction caused by total occlusion of the left main coronary artery (LMCA-AMI). Thus, we surveyed these patients, and attempted to elucidate helpful predictors related to the prognosis. Six of 13 patients with LMCA-AMI survived. Successful left coronary artery dilatation was achieved in all survivors (group S), and in 5 (71%) non-survivors (group non-S). The age was not different between the two groups. A past history of angina was confirmed in 83% of group S. while only in 29% of group non-S. Clinical findings such as time of onset of AMI, interval from the AMI onset to admission, elapsed period from the AMI onset to recanalization of LMCA and the value of CK on admission were not different between the two groups. However, cardiogenic shock occurred in only 1 patient (17%) in group S compared with 5 patients (71%) in group non-S. As emphasized in the literature, good collateral circulation to the left anterior descending artery was observed in 5 patients (83%) in group S, while not observed in group non-S. Electro cardiographically, ST elevation in the aVR lead was very characteristic. This finding was confirmed in 69% of the total patients. Noticeably, 5 out of 6 non-survivors (83%) showed ST elevation not only in leads aVR but also in the aVL lead. In addition to the absence of collateral circulation, this electrocardiographic finding, which obviously indicates the presence of extensive myocardial ischemia in the diseased heart, is a simple and important predictor suggesting a poor prognosis in LMCA-AMI patients.

A prospective study of elective stenting in unprotected left main coronary disease

The standard treatment of left main coronary artery (LMCA) disease has been bypass surgery (CABG). Recent reports suggested that stenting of LMCA disease might be feasible. From January 1995 to April 1998, we carried out a prospective study of elective stenting of unprotected LMCA disease to evaluate its immediate and long-term results. Of 61 consecutive patients with unprotected LMCA disease, 6 were excluded. Acute procedural success was 100% for the remaining 55 patients, without any complications such as stent thrombosis, myocardial infarction, CABG, or death. During a mean follow-up of 16.1+/-9.6 months, 11 patients (20%) had symptomatic recurrence, between 2 to 6 months after their procedure. Seven patients underwent CABG, two had repeat intervention, one continued with medical therapy, and one died before planned angiography. There was no late sudden death. Forty-four patients (80%) remained asymptomatic. We conclude that elective stenting may be a safe alternative to CABG in unprotected LMCA disease.

Intravascular ultrasound predictors of target lesion revascularization after stenting of protected left main coronary artery stenoses

We evaluated the predictors of late clinical outcomes after stenting of protected left main coronary artery (LMCA) stenoses. Intravascular ultrasound (IVUS) guided stenting of protected LMCA stenoses was performed in 87 consecutive patients between January 1994 and December 1996. Results were evaluated using conventional (clinical, angiographic, and IVUS) methodology. Late (12 month) clinical follow-up information was obtained in all patients. Initial procedural success was achieved in 86 patients (99%). There was 1 in-hospital death (in the 1 patient with a procedural failure). There were no other in-hospital complications, including Q-wave myocardial infarction, emergency bypass surgery, or repeat coronary angioplasty. The overall target lesion revascularization (TLR) rate was 13%. Using multivariate logistic regression analysis, the only independent predictor of TLR was the postintervention lumen area by IVUS. A final lumen area > or =7.0 mm2 was obtained in 74 patients (86%); the TLR rate for these patients was 7%. This was compared with patients with a final lumen area <7.0 mm2 in whom the TLR rate was 50% (p = 0.0011). Stenting of protected LMCA stenoses is safe and effective with acceptable long-term clinical outcomes. The most important factor determining long-term success was the postintervention lumen area by IVUS.

Emergency left main stenting in the management of postcoronary bypass graft surgery (CABG) ischemia

Angioplasty has been used in the management of postcoronary bypass graft myocardial ischemia/infarction. A stent was successfully deployed in the left main artery in a patient with postcoronary bypass graft ischemia with hemodynamic instability. This case illustrates the potential use of emergency left main stenting in a selected patient with peri-operative ischemia, who was considered high risk for re-operation.

Bail-out stenting of the unprotected left main stem

Two cases of life-threatening left main stem (LMS) complications during routine cardiac catheterization were successfully treated with intracoronary stenting prior to successful emergency bypass surgery. Intracoronary stenting is of value in stabilising patients before emergency bypass surgery and can save lives in LMS complications.

[Emergency implantation of intracoronary stent after acute occlusion of the common trunk of the left coronary artery]

Nowadays, the implantation of coronary endoprosthesis within the left main coronary artery is not considered as an absolute contraindication. Here, we show a case of acute occlusion within the left main coronary artery. This was resolved by implanting a stent during a programmed cardiac catheterization. It should be stressed that this problem was occurred without manipulating the left coronary tree. In addition, the patient was in cardiac arrest when the stent was implanted. Cardiopulmonary resuscitation was applied because of this condition.

Stenting of unprotected left main coronary artery stenoses: immediate and late outcomes

OBJECTIVES

We examined the immediate and long-term outcomes after stenting of unprotected left main coronary artery (LMCA) stenoses in patients with normal left ventricular (LV) function.

BACKGROUND

Left main coronary artery disease is regarded as an absolute contraindication for coronary angioplasty. Recently, several reports on protected or unprotected LMCA stenting, or both, suggested the possibility of percutaneous intervention for this prohibited area.

METHODS

Forty-two consecutive patients with unprotected LMCA stenoses and normal LV function were treated with stents. The post-stent antithrombotic regimens were aspirin and ticlopidine; 14 patients also received warfarin. Patients were followed very closely with monthly telephone interviews and follow-up angiography at 6 months.

RESULTS

The procedural success rate was 100%, with no episodes of subacute thrombosis regardless of anticoagulation regimen. Six-month follow-up angiography was performed in 32 of 34 eligible patients. Angiographic restenosis occurred in seven patients (22%, 95% confidence interval 7% to 37%); five patients subsequently underwent elective coronary artery bypass graft surgery (CABG), and two patients were treated with rotational atherectomy plus adjunct balloon angioplasty. The only death occurred 2 days after elective CABG for treatment of in-stent restenosis. The other patients (without angiographic follow-up) remain asymptomatic.

CONCLUSIONS

Stenting of unprotected LMCA stenoses may be a safe and effective alternative to CABG in carefully selected patients with normal LV function. Further studies in larger patient populations are needed to assess late outcome.

Mortality related to diagnostic cardiac catheterization. The importance of left main coronary disease and catheter induced trauma

BACKGROUND

The mortality of diagnostic catheterization is very low but still exists. Large series have documented left main disease as the most important anatomical risk factor but have not clarified the mechanism.

OBJECTIVES

To determine the mortality of diagnostic catheterization in a single high volume centre over a 9 year period and assess any change during this period; to compare this experience with that of larger multicentre surveys; to identify the clinical and anatomical risk factors; to investigate the mechanism of the event; to develop guidelines for prevention

METHODS

Cardiac catheterization records were reviewed over a 9 year period and patients dying during or within 24 hours were identified. The clinical and anatomical profile of the patients who died were compared with the overall group to search for independent risk factors. The angiograms of the deaths were reviewed for a mechanism.

RESULTS

There were 30 deaths in 42,345 procedures (0.071%). There was no change in the incidence over the 9 years. Left main coronary disease was an overwhelming risk factor (incidence 0.7%, p < .002 compared to all other subgroups) and no other anatomical subgroup including triple vessel disease was at greater risk than the overall group. Dissection of the left main coronary artery by the diagnostic catheter was the mechanism of death in 20 cases (67%)

CONCLUSIONS

Left main disease and catheter induced trauma are the most important risk factor for and mechanism of death during diagnostic catheterization and may account for the unchanging incidence. Technical guidelines are described which may reduce this risk.

Percutaneous treatment of protected and unprotected left main coronary stenoses with new devices: immediate angiographic results and intermediate-term follow-up

OBJECTIVES

We sought to evaluate the immediate angiographic results and intermediate-term follow-up after percutaneous treatment of left main coronary stenoses in the new device era.

BACKGROUND

Historically, balloon angioplasty of left main coronary stenoses has been associated with high procedural morbidity and poor long-term results. It is not clear whether new devices are more effective in this anatomic setting.

METHODS

Between July 1993 and July 1995, we performed initial left main coronary interventions on 46 patients (mean age 67 +/- 12 years, 26% women). Quantitative angiography was available for 42 of 46 interventions, and clinical follow-up was obtained for all patients at 1 month, 6 months and 1 year after initial revascularization.

RESULTS

Most interventions (42 of 46) were performed in patients with "protected" coronary stenoses to the left coronary system owing to the presence of one or more patent left main coronary grafts. Seventy-seven percent of screened patients were deemed unsuitable for repeat coronary artery bypass surgery. Procedures performed included stenting in 73% of patients (alone in 30% and after rotational atherectomy in 43%), rotational atherectomy in 58% (alone in 15% and before stenting in 43%), directional atherectomy in 4% and angioplasty alone in 7%. Initial procedural success was achieved in all interventions, with no deaths, myocardial infarctions (creatine kinase, MB fraction > 50 IU/liter) or emergent bypass surgery. Follow-up data to date (median duration 9 months, range 6 to 19) demonstrate a 98% overall survival rate and a 6-month event-free survival rate of 78% (six target vessel revascularizations [TVRs], four non-TVRs).

CONCLUSIONS

Treatment of protected left main coronary artery stenoses can be accomplished safely and effectively with new device technology. Intermediate-term follow-up demonstrates an acceptably low rate of death, myocardial infarction or repeat revascularization at 6 months and 1 year.

Port-access bilateral internal mammary artery grafting for left main coronary artery disease: canine feasibility study

BACKGROUND

To extend the applications of minimal access cardiac surgery, an endovascular cardiopulmonary bypass (CPB) system that allows cardioplegia delivery and cardiac venting was used to perform bilateral internal mammary artery (IMA) bypass grafting in six dogs.

METHODS

The left IMA (LIMA) was taken down thoracoscopically from three left lateral chest ports, followed by the right IMA (RIMA) from the right side. One left-sided port was extended medially 5 cm with or without rib resection, to expose the pericardium. Both IMAs were divided and exteriorized through the left anterior mediastinotomy. Flow and pedicle length were satisfactory in all cases. Femoral-femoral bypass was used and the heart arrested with antegrade delivery of cardioplegic solution via the central lumen of a balloon catheter inflated to occlude the ascending aorta. All anastomoses were made through the mediastinotomy under direct vision. In five studies the RIMA was attached to the left anterior descending artery (LAD) and the LIMA to the circumflex, and in one study the RIMA was tunneled through the transverse sinus to the circumflex and the LIMA was anastomosed to the LAD. All animals were weaned from CPB in sinus rhythm without inotropes. CPB duration was 108 +/- 27 minutes (mean +/- SD) and the clamp duration was 54 +/- 10 minutes.

RESULTS

Preoperative and postoperative cardiac outputs were 2.9 +/- 0.71/min and 2.4 +/- 0.31/min, respectively (p = NS), and corresponding pulmonary artery occlusion pressures were 6 +/- 3 mmHg and 7 +/- 2 mmHg, respectively (p = NS). All 12 grafts were demonstrated to be fully patent. Postmortem examination revealed well aligned pedicles and correctly grafted target vessels.

CONCLUSION

This canine model demonstrates the potential for a less invasive approach to the surgical management of left main coronary artery disease in humans.

Elective stenting of unprotected left main coronary disease

For the 12-mo period of 1995, we encountered seven consecutive patients with symptomatic unprotected left main coronary stenosis requiring revascularization. There were five males and two females, age ranging 48-76 years. One patient was referred to coronary bypass surgery. Of the remaining six patients, three refused surgery and the other three, including one with previous bypass surgery and two with previous interventional procedures, preferred percutaneous revascularization. All six had successful elective stenting of their left main coronary stenoses with the new short Palmaz-Schatz stents, P084 and PS104. There were no complications and all remained totally asymptomatic at 3-14 months followup. We conclude that with proper patient selection and the availability of appropriate stents, elective stenting of unprotected left main coronary stenosis is safe with good immediate and medium term results.

Coronary artery stenting: indications and cost implications

The practice of coronary stenting is evolving rapidly, with new stent designs, deployment techniques, and adjunctive therapy. In many respects, clinical practice is changing in advance of the availability of supporting data. The consistent excellent angiographic result with stent deployment exceeds that achieved by any other previous interventional device, and the extent to which this accounts for the exponential increase in stent utilization cannot be accurately determined but is undoubtedly considerable. Controlled randomized trials have confirmed that stent deployment is superior to balloon angioplasty in certain lesion subsets or clinical scenarios. These include focal de novo native vessel lesions, lesions with late recoil after balloon angioplasty, acute closure after balloon angioplasty, and proximal left anterior descending coronary artery lesions. In addition, observational data is persuasive in focal coronary saphenous vein graft lesions and aorto-ostial lesions. On the other hand, the evidence supporting the use of stents strictly to improve on a suboptimal result, possibly the most frequent indication, is indirect and circumstantial. Stents are expensive, but it was anticipated that with the reduction in restenosis not only would they be cost-effective but also ultimately would reduce costs. This hope has not as yet been realized. However, there is little question that the introduction of intracoronary stents has been the most significant and exciting development since the introduction of percutaneous revascularization almost 20 years ago. It has revitalized the field.

Treatment of unprotected left main stenoses with Palmaz-Schatz stenting

Coronary artery bypass surgery remains the standard modality for revascularization of significant left main coronary artery stenoses. Despite major improvement in equipment and operator technique, balloon angioplasty of significant unprotected left main obstruction generally is contraindicated. When catheter intervention is required, Palmaz-Schatz stenting may offer better predictability of the acute result, and possibly improved long-term outcome.

Stent implantation of saphenous vein graft aorto-ostial lesions in patients with unstable ischemic syndromes: immediate angiographic results and long-term clinical outcome

OBJECTIVES

This study examined the immediate angiographic and long-term clinical results of stenting saphenous vein graft aorto-ostial stenosis at a single center.

BACKGROUND

Data on the feasibility, safety and short- and long-term clinical results of stent implantation in aorto-ostial lesions in patients with unstable angina are limited.

METHODS

Palmaz or Palmaz-Schatz stents were deployed in 29 patients (mean [+/- SD] age 70 +/- 10 years) with complex (B2 or C) vein graft aorto-ostial lesion morphology. All patients had angina at rest; 23 (79%) had a previous myocardial infarction; and 13 (45%) had two previous bypass operations (mean graft age 9 +/- 5 years). Mean left ventricular ejection fraction was 42 +/- 13%.

RESULTS

Thirty-two stents were deployed in 25 new and 4 restenotic aorto-ostial lesions. Ten additional stents were implanted in five patients for eight lesions other than at ostial locations. Stent implantation was successful in all patients. There was no death, Q wave myocardial infarction, bypass surgery or stent thrombosis in the first 30 days. Stenting improved minimal lumen diameter from 0.7 +/- 0.5 mm (95% confidence interval [CI] 0.5 to 0.8) to 3.3 +/- 0.5 mm (CI 3.2 to 3.5) and percent diameter stenosis from 80 +/- 13% (CI 75% to 85%) to 1 +/- 12% (CI -3% to 6%) (p < 0.001 for both variables). Immediate loss from recoil was 0.2 +/- 0.2 mm (CI 0.2 to 0.3), corresponding to a percent recoil of 7 +/- 5% (CI 5% to 9%). Clinical follow-up in all patients at a mean of 11 +/- 8 months revealed that 27 patients (94%) were free of death or myocardial infarction. Bypass surgery and balloon angioplasty were required in one (3%) and two (6%) patients, respectively. In 21 (88%) of the remaining 24 patients, symptoms were lessened by two or more symptom classes.

CONCLUSIONS

Palmaz or Palmaz-Schatz stent implantation for saphenous vein graft aorto-ostial stenosis has a high likelihood of immediate success and is associated with a large immediate gain in lumen diameter. Thirty-day and long-term adverse event rates are low. These data suggest that stenting saphenous vein graft aorto-ostial lesions is an acceptable therapeutic option in selected elderly patients with unstable angina and large-diameter vessels.