Three-year follow-up after implantation of metallic coronary-artery stents

Does angiography six months after coronary intervention influence management and outcome? Benestent II Investigators

OBJECTIVES

This study was performed to assess whether angiography six months after coronary balloon angioplasty or stent implantation has an influence on clinical management and one-year outcome.

BACKGROUND

The Benestent II study randomized 827 patients to balloon angioplasty or stent implantation. A subrandomization was undertaken allocating patients to six-month clinical follow-up (CF) or clinical and angiographic follow-up (AF).

METHODS

Seven hundred and six patients (349 CF and 357 AF) had no intercurrent angiography, so that restenosis and disease progression elsewhere remained unknown until the time of six-month follow-up. These two groups, which were well matched at enrolment, were compared with respect to symptoms, medication and major cardiac events defined as death, myocardial infarction and need for revascularization at six and 12 months.

RESULTS

At six-month follow-up, 53 (15%) of the CF and 76 (21%) of the AF patients had stable angina (p = 0.041), while 5 (1%) and 4 (1%) had symptoms of unstable angina. At 12-month follow-up, 44 (13%) patients in both groups had stable angina, and only 1 patient in the CF group had unstable angina. Seventy-seven patients (27 CF and 50 AF; p < 0.01) had major cardiac events between 6 and 12 months. Of the 349 patients in the CF group, 21 underwent repeat percutaneous transluminal coronary angioplasty or coronary artery bypass graft surgery between 6 and 12 months, compared with 44 of the 357 patients in the AF group (relative risk 2.05 [1.24 to 3.37], p = 0.003).

CONCLUSIONS

Patients who had AF six months after balloon angioplasty or stent implantation experienced more repeat revascularization procedures than those who had CF. They also had significantly more angina at six-month follow-up but this may be due to bias.

Coronary stent deployment without predilation in acute myocardial infarction: a feasible, safe, and effective technique

Direct percutaneous transcatheter revascularization (PTCR) is becoming an acceptable therapy for acute myocardial infarction (AMI). Stenting in the setting of AMI, once considered contraindicated, is emerging as a suitable option in this situation. Coronary stenting without predilation (SWOP) may potentially shorten the procedure and radiation time, reduce costs, and decrease procedural complications such as coronary dissection and distal embolization. It is expected to cause less vascular injury, with a reduction in the rate of in-stent restenosis. In this preliminary study the authors evaluated the feasibility of the SWOP procedure in 22 selected patients with AMI. Indications for catheter-based myocardial reperfusion were the following: extensive anterior wall MI (68%), inferior wall and right ventricular MI (23%), and inferior wall MI with contraindication for thrombolytic therapy (9%). Patients with cardiogenic shock or with contraindications for aspirin or ticlopidine were excluded. SWOP was successful in 21 attempts (95%), and final procedural success was achieved in all. Proximal or distal dissections were seen in three cases and were treated by additional three stents. Thrombolysis in myocardial infarction (TIMI) flow 3 was restored in all patients. There were no distal embolizations, side branch occlusions, coronary perforations, procedure-related emergency bypass operations, or deaths. It is concluded that in selected patients with AMI, coronary artery stenting without predilation is feasible and safe and does not introduce additional risk to the patients.

Final results of the STent versus directional coronary Atherectomy Randomized Trial (START)

OBJECTIVES

This study was designed to compare primary stenting with optimal directional coronary atherectomy (DCA).

BACKGROUND

No previous prospective randomized trial comparing stenting and DCA has been performed.

METHODS

One hundred and twenty-two lesions suitable for both Palmaz-Schatz stenting and DCA were randomly assigned to stent (62 lesions) or DCA (60 lesions) arm. Single or multiple stents were implanted with high-pressure dilation in the stent arm. Aggressive debulking using intravascular ultrasound (IVUS) was performed in the DCA arm. Serial quantitative angiography and IVUS were performed preprocedure, postprocedure and at six months. The primary end point was restenosis, defined as > or =50% diameter stenosis at six months. Clinical event rates at one year were also assessed.

RESULTS

Baseline characteristics were similar. Procedural success was achieved in all lesions. Although the postprocedural lumen diameter was similar (2.79 vs. 2.90 mm, stent vs. DCA), the follow-up lumen diameter was significantly smaller (1.89 vs. 2.18 mm; p = 0.023) in the stent arm. The IVUS revealed that intimal proliferation was significantly larger in the stent arm than in the DCA arm (3.1 vs. 1.1 mm ; p < 0.0001), which accounted for the significantly smaller follow-up lumen area of the stent arm (5.3 vs. 7.0 mm2; p = 0.030). Restenosis was significantly lower (32.8% vs. 15.8%; p = 0.032), and target vessel failure at one year tended to be lower in the DCA arm (33.9% vs. 18.3%; p = 0.056).

CONCLUSIONS

These results suggest that aggressive DCA may provide superior angiographic and clinical outcomes to primary stenting.

Long term outcome after coronary stent implantation: a 10 year single centre experience of 1000 patients

OBJECTIVE

To describe the long term clinical outcome (up to 11 years) after coronary stenting.

DESIGN

A single centre observational study encompassing 1000 consecutive patients with a first stent implantation (1560 stents) between 1986 and 1996, who were followed for at least one year with a median follow up of 29 months (range 12-132 months).

RESULTS

Up to July 1997 the cumulative incidence of the major adverse cardiac events (MACE) of death, non-fatal acute myocardial infarction, coronary artery bypass grafting, and repeat percutaneous transluminal coronary angioplasty was 8.2%, 12.8%, 13.1%, and 22.4%, respectively. Survival at one, three, and five years was 95%, 91%, and 86%, respectively. Comparison of MACE incidence during the "anticoagulant era" and the "ticlopidine era" revealed significantly improved event free survival with ticlopidine (27% v 13%; p < 0.005). Multivariable analyses showed that ejection fraction < 50% (relative risk (RR) 4. 1), multivessel disease (RR 3.0), diabetes (RR 2.9), implantation in saphenous vein graft (RR 2.1), indication for unstable angina (RR 1. 9), and female sex (RR 1.7) were independent predictors of increased mortality after stenting. Independent predictors of any MACE were multivessel stenting (RR 2.0), implantation in saphenous bypass graft (RR 1.6), diabetes (RR 1.5), anticoagulant treatment (versus ticlopidine and aspirin) (RR 1.5), bailout stenting (RR 1.5), multivessel disease (RR 1.4), and multiple stent implantation (RR 1. 5).

CONCLUSIONS

Long term survival and infarct free survival was good, particularly in non-diabetic men with single vessel disease and good ventricular function, who had a single stent implanted in a native coronary artery. A dramatic improvement was observed in event free survival, both early and late, with the replacement of anticoagulation by ticlopidine. This, of course, cannot be separated from improved stent implantation techniques between 1986 and 1995. Ultimately, almost 40% of the patients experienced an adverse cardiac event (mainly repeat intervention) in the long term. New advances in restenosis treatments and in secondary prevention must be directed at this aspect of patient management after stenting.

Short- and long-term outcomes of Wiktor stent implantation at low versus high pressures. Austrian Wiktor Stent Study Group

A prospective, randomized, multicenter trial was conducted to evaluate whether high-pressure postdilation of the Wiktor stent provides short- and long-term benefits compared with the conventional low-pressure implantation technique. From June 1995 through May 1996, 181 patients were randomly assigned to either low-pressure (6 to 12 atm, group A, n = 94) Wiktor stent placement or to high-pressure postdilation (> or = 13 atm, group B, n = 87) after stent deployment. All patients were followed up clinically for 7 +/- 3 months, with an angiographic follow-up in 154 patients (85%). After stent implantation, neither minimal lumen diameter (MLD) nor percent diameter stenosis (%DS) differed significantly between the 2 groups (MLD, 2.8 +/- 0.5 vs 2.9 +/- 0.5 mm; %DS, 17 +/- 8% vs 16 +/- 9% for groups A and B, respectively). However, a trend toward a larger mean lumen diameter within the stent was observed in group B (3.3 +/- 0.6 vs 3.5 +/- 0.5 mm for groups A and B, respectively; difference between means 0.14 mm, 95% confidence interval -0.01 to 0.29, p = 0.08). Angiographic follow-up revealed similar MLD and %DS in both treatment groups (MLD, 2.1 +/- 0.7 vs 2.2 +/- 0.8 mm; %DS, 31 +/- 17% vs 30 +/- 24% for groups A and B, respectively, p = NS). Acute stent thrombosis occurred in 2 patients (1%) (1 patient in each group), and subacute thrombosis in 1 patient (0.6%) in group A. There was 1 death in group A, and target lesion restenosis (> or = 50% DS) was observed in 15% of patients with no differences between the groups. In conclusion, this study demonstrated favorable short- and long-term results of Wiktor stent implantation. Despite a trend toward additional initial lumen gain by high-pressure postdilation, this did not translate into a measurable improvement in long-term outcome.

Atherosclerotic renal artery stenosis: from diagnosis to treatment

Renovascular hypertension represents a form of correctable hypertension and preventable renal failure. Such patients need to be identified early so that specific therapy can be instigated. Patient identification requires a high index of suspicion in patients with certain clinical features. Subsequent non-invasive imaging may result in angiography which is required for diagnostic purposes and for planning intervention. Correctable therapy takes one of two forms, namely percutaneous transluminal renal angioplasty, with or without stenting, or surgical revascularisation, together with modification of underlying risk factors.

Angioplasty and stenting of basilar artery stenosis: technical case report

OBJECTIVE AND IMPORTANCE

Symptomatic basilar artery stenosis has a poor prognosis. Treatment options are limited. Surgical bypasses are technically demanding and of no proven benefit. Percutaneous angioplasty is associated with a significant complication rate, because of intraplaque dissection, restenosis secondary to vessel recoil, and embolic phenomena. A new generation of intravascular stents that are flexible enough to navigate the tortuosities of the vertebral artery may provide a new therapeutic approach. We report a case of basilar artery stenosis that was treated using stent-assisted angioplasty.

CLINICAL PRESENTATION

A 56-year-old woman experienced a vertebrobasilar ischemic stroke, from which she recovered. Magnetic resonance angiography revealed severe proximal basilar artery stenosis. Brain Neurolite-single-photon emission computed tomographic scans revealed significantly decreased perfusion of the brainstem. Endovascular intra-arterial pressure measurements revealed a 35-mm Hg gradient across the lesion.

INTERVENTION

The patient underwent uncomplicated angioplasty and stenting of the proximal basilar artery, with excellent angiographic results.

CONCLUSION

The availability of new flexible intravascular stents, allowing access to tortuous proximal intracranial vessels, provides a new therapeutic approach for patients with basilar artery stenosis. Long-term follow-up monitoring is required to assess the durability of this approach.

Continued expansion of the nitinol self-expanding coronary stent: angiographic analysis and 1-year clinical follow-up

BACKGROUND

This study sought to report the first-year clinical outcome with the nitinol self-expanding coil stent and to provide angiographic data on the effect of self-expansion during implantation and follow-up. Self-expanding stents do not reach their nominal diameter at implantation. The long-term effects may therefore depend, in part, on continued expansion after initial implantation.

METHODS

Between January 1995 and January 1996, 86 stents were deployed in 64 patients for indication of suboptimal results. All patients were clinically followed up for 1 year, and 72% had follow-up angiography.

RESULTS

The majority (55%) of the lesions were class B2 or C. Balloon angioplasty increased the minimal lumen diameter from 1.07 +/- 0.73 mm to 2.24 +/- 0.57 mm; stent deployment further increased the diameter to 2.63 +/- 0.48 mm, and within-stent balloon dilatation to 2.96 +/- 0.62 mm. Angiographic follow-up performed at 7.8 +/- 1.1 months (range 7-9 months) showed that the minimal lumen diameter was 2.15 +/- 0.80 mm (late lumen loss of 0.81 +/- 0.69 mm), and the mean stent diameter expanded to 3.58 +/- 0.48 mm (self-expanding late stent gain of 0.62 +/- 0.55 mm). The extent of this expansion was inversely related to the late lumen loss (r = 0.67, slope 0.81, P <.01). At 1 year 51 (80%) of 64 patients were event free; 3 had undergone coronary artery bypass grafting, 2 had had a myocardial infarction, and 9 had repeat angioplasty. In the subgroup of a simple lesion (<15 mm) covered by 1 stent, 18 (86%) of 21 patients were event free.

CONCLUSIONS

The self-expanding nitinol stent exerts its acute effect on minimal lumen diameter through its intrinsic radial force aided by balloon expansion. The stent continues to expand until it reaches its nominal diameter over the follow-up period. The extent of this expansion is inversely related to the late lumen loss, leading to an acceptable rate of long-term clinical events in this first cohort of patients with complex disease morphology.

Direct coronary stenting without balloon predilation in acute coronary syndromes

BACKGROUND

This prospective, observational study was designed to evaluate the feasibility and the safety of a new strategy for stenting in acute coronary syndromes: direct stent implantation without predilation of the culprit lesion. This strategy might reduce both the cost of the procedure and the rate of no-reflow, a phenomenon that is more frequently observed during dilation of unstable plaques.

METHODS AND RESULTS

Between September 1997 and March 1998, 122 carefully selected patients with unstable angina or acute myocardial infarction were included in this study. Highly calcified lesions and vessels with excessive proximal tortuosity were excluded. The procedure was successful in 96% of cases. In 5 cases the stent failed to pass through the stenosis and was successfully retrieved in the guiding catheter in 3 cases. In 2 cases the stent was lost in the peripheral circulation. Transient no-reflow occurred in only 3 cases and was rapidly reversed by rescue use of an intracoronary bolus injection of a glycoprotein IIb/IIIa receptor inhibitor in 2 cases. A patient treated by primary angioplasty with cardiogenic shock on admission died 48 hours after the initial procedure because of irreversible cardiac failure. One-month clinical follow-up was obtained by telephone for all patients; no major coronary events occurred during this period.

CONCLUSIONS

Direct coronary stenting without balloon predilation can be safely performed in acute coronary syndrome-related lesions in selected patients. A randomized, controlled study is warranted to confirm the promising results of this pilot study, especially regarding the low rate of the no-reflow phenomenon.

Intravascular ultrasound-guided balloon angioplasty for treatment of in-stent restenosis

We investigated the usefulness of intravascular ultrasound (IVUS)-guided balloon angioplasty for in-stent restenosis in 37 lesions of 34 consecutive patients. We divided these patients into two groups: a group in which the balloon size was determined by quantitative coronary angiography (QCA group; 17 patients, 19 lesions) and a group in which the balloon size was determined by IVUS (IVUS group; 17 patients, 18 lesions). We compared short-term and 6-month outcomes for these groups. In the IVUS group, we used a balloon of a size equal to 95% of the media-to-media diameter at the distal to the stent, as determined by IVUS. No significant differences were observed in patient or lesion characteristics between the two groups. The clinical success rate was 100% in both groups, and no clinical events were observed in either of the groups. The balloon/artery ratio was larger in the IVUS group than in the QCA group (1.33 +/- 0.35 vs. 1.16 +/- 0.13, P < 0.05), and the recurrent restenosis rate was lower (17% vs. 53%, P < 0.05). These results suggest that repeat balloon angioplasty using a balloon size determined by IVUS is useful for in-stent restenosis. Cathet. Cardiovasc. Intervent. 47:298-303, 1999.

Effectiveness of coronary stent deployment without predilation

The feasibility of coronary stenting without predilation is demonstrated in 240 patients. In all, 249 stents were placed. Primary implantation was successful in 93% of cases. In 17 lesions the stents could not be advanced through the stenotic lesion. The unexpanded stents were removed through the guiding catheter, and stenting was performed after prediction. Minor complications (side branch compromise and intimal dissection), which were successfully treated, occurred in 26 patients (10.6%).

Effects of a positron-emitting vanadium-48 nitinol stent on experimental restenosis in porcine coronary arteries: an injury-response study

BACKGROUND

The major limitation of coronary stenting is restenosis due to exaggerated neointimal thickening. We evaluated a positron-emitting V48 nitinol stent in a porcine coronary model of restenosis.

METHODS AND RESULTS

Pigs (n = 16) received a control nonradioactive and a V48 stent (1.5 or 10.6 muCi) randomized to the left anterior descending artery (LAD) and right coronary artery (RCA). Histology, morphometric variables, and strut injury scores were evaluated after 32 days. Peristrut fibrinoid deposits were greater in the high-dose group (p < 0.0001). Control stent area stenosis (AS) and mean neointimal thickness (NIT) correlated with injury (r = 0.81 and 0.79, respectively). Higher-dose stents reduced AS by 20% (0.57 +/- 0.13 vs. 0.71 +/- 0.16; p = 0.029) and mean NIT by 35% (0.44 +/- 0.16 vs. 0.71 +/- 0.24mm; p = 0.001) compared with controls. Lower-dose 1.5-muCi stents did not differ from controls. NIT over individual struts was reduced in the high-dose group compared with controls by 0.18 mm for grade 1 injury, 0.31 mm for grade 2, and 0.38 mm for grade 3 (p < 0.02 for all comparisons).

CONCLUSIONS

1.5-muCi V48 nitinol stents did not influence vessel histology or restenotic parameters in pig coronary arteries. In contrast, 10.6-muCi stents created a distinctive histological picture consisting of increased fibrinoid deposits on the neointimal-facing side of the struts without cellular organization. Higher dose radioactive stents significantly reduced AS and mean NIT. The reduction in neointimal thickening was greatest when the depth of strut penetration into the vascular wall was most severe.

[The therapeutic focus in severe hypertrophic obstructive cardiomyopathy with multivessel coronary disease]

The association of severe hypertrophic obstructive cardiomyopathy and coronary artery disease increases surgical morbimortality, even more in patients over 65 years. We describe a combined therapeutic approach to these diseases. A 68-year-old woman with a diagnosis of hypertrophic obstructive cardiomyopathy was in functional class IV for angina and dyspnea despite 360 mg of propranolol a day. An echocardiogram and a complete cardiac catheterization were performed under betablocker therapy, confirming a severe hypertrophic obstructive cardiomyopathy and revealing severe stenosis in the proximal left circumflex and the proximal right coronary arteries, and a moderate lesion in the mid-left anterior descendent. They were both treated with balloon PTCA, and a 3 x 15 mm stent was placed in the circumflex and a 3.5 x 20 mm stent in the right coronary, with an excellent angiographic result. A basal hemodynamic study was then performed and A-V sequential pacing was attempted, achieving a significant decrease in the left ventricle outflow tract gradient. A DDD-R pacemaker was implanted. Echocardiographic study was performed post-implantation, and follow-up was made six months later with a new coronary angiography, hemodynamic study and a Doppler echocardiogram. At the present time A-V sequential pacing as a therapeutic option for hypertrophic obstructive cardiomyopathy and coronary angioplasty and stenting for the treatment of coronary artery disease are sufficiently established and supported to be offered as a combined therapy to patients suffering from both diseases, specially those with a higher surgical risk.

Relationship between blood flow, thrombus, and neointima in stents

PURPOSE

To establish a relationship between flow, acute thrombus formation, and late intimal hyperplasia in arterial stents.

MATERIALS AND METHODS

To compare short-term stent patency in the canine femoral artery with normal flow to that in the opposite femoral artery with restricted flow, 24 dogs were subdivided in four groups: groups 1 (no intravenous heparin) and 2 (intravenous heparin) had unilateral flow restriction by surgically created stenosis, downstream of a Palmaz stent. Group 3 (no intravenous heparin) and 4 (intravenous heparin) had sham surgical exposure of the corresponding arterial segment, without flow restriction. Thrombocyte activity over the stent segment was evaluated for 3 hours after stent placement with nuclear scanning, after administration of indium-111-labeled platelets. To evaluate long-term stent patency in relationship to arterial flow, 14 additional dogs were subjected to long-term observation. Matched, symmetrically implanted femoral stents with normal and restricted flow, were explanted at 1, 12, and 24 weeks for histologic analysis and comparative measurement of neointimal thickness. Angiographic studies were performed before and after nuclear scanning in the short-term study group and before explant in the long-term animal group.

RESULTS

In the short-term, groups 2 and 4 showed neither increased platelet uptake nor angiographically demonstrable thrombus. Group 1 had increased platelet uptake and occlusive or subocclusive angiographic thrombus. Group 3 had increased platelet uptake and angiographic thrombus in one instance. In the long-term, stents with flow restriction had significantly greater neointimal formation in comparison with unrestricted stents. Histologic studies suggested that the stent neointima resulted from progressive replacement of stent thrombus.

CONCLUSION

Regardless of flow condition, intravenous heparinization is necessary to prevent thrombus formation in the stent lumen. Within the experimental parameters of this study, low flow and absent heparinization consistently lead to stent thrombosis. Stent implantation under low flow is associated with increased neointima formation. It is not known whether this is preventable by antithrombotic medication.

Percutaneous transluminal angioplasty and stent placement for recurrent carotid artery stenosis

OBJECT

Treatment consisting of percutaneous transluminal angioplasty (PTA) and stent placement has recently been proposed as an alternative to surgical reexploration in patients with recurrent carotid artery stenosis following endarterectomy. The authors retrospectively reviewed their experience after performing 25 procedures in 21 patients to assess the safety and efficacy of PTA with or without stent placement for carotid artery restenosis.

METHODS

The mean interval between endarterectomy and the endovascular procedures was 57 months (range 8-220 months). Seven arteries in five patients were treated by PTA alone (including bilateral procedures in one patient and repeated angioplasty in the same vessel in another). Early suboptimum results and recurrent stenosis in some of these initial cases prompted the authors to combine PTA with stent placement in the treatment of 18 arteries over the past 3 years. No major periprocedural deficits (neurological or cardiac complications) or death occurred. There was one periprocedural transient neurological event, and in one patient a pseudoaneurysm of the femoral artery (at the access site) required surgical repair. In the 16 patients who each underwent at least 6 months of follow-up review, no neurological events ipsilateral to the treated artery had occurred after a mean follow-up period of 27 months (range 6-57 months). Three of five patients who underwent PTA alone developed significant (>50%) asymptomatic restenoses that required repeated angioplasty in one and PTA with stent placement in two patients. Significant restenosis (55%) was observed in only one of the vessels treated by combined angioplasty and stent placement.

CONCLUSIONS

Endovascular PTA and stenting of recurrent carotid artery stenosis is both technically feasible and safe and has a satisfactory midterm patency. This procedure can be considered a viable alternative to surgical reexploration in patients with recurrent carotid artery stenosis.

Clinical and angiographic follow-Up after primary stenting in acute myocardial infarction: the Primary Angioplasty in Myocardial Infarction (PAMI) stent pilot trial

BACKGROUND

Restenosis has been reported in as many as 50% of patients within 6 months after PTCA in acute myocardial infarction (AMI), which necessitates repeat target-vessel revascularization (TVR) in approximately 20% of patients during this time period. Routine (primary) stent implantation after PTCA has the potential to further improve late outcomes.

METHODS AND RESULTS

Primary stenting was performed as part of a prospective study in 236 consecutive patients without contraindications who presented with AMI of <12 hours' duration at 9 international centers. A mean of 1.4+/-0.7 stents were implanted per patient (97% Palmaz-Schatz) at 17.3+/-2.4 atm. During a clinical follow-up period of 7.4+/-2.6 months, death occurred in 4 patients (1.7%), reinfarction occurred in 5 patients (2.1%), and TVR was required in 26 patients (11.1%). By Cox regression analysis, small reference-vessel diameter and the number of stents implanted were the strongest determinants of TVR. Angiographic restenosis occurred in 27.5% of lesions. By multiple logistic regression analysis, the number of stents implanted and the absence of thrombus on the baseline angiogram were independent determinants of binary restenosis.

CONCLUSIONS

A strategy of routine stent implantation during mechanical reperfusion of AMI is safe and is associated with favorable event-free survival and low rates of restenosis compared with primary PTCA alone.

Outcome of target sites escaping high-grade (>70%) restenosis after percutaneous transluminal coronary angioplasty

This study examined the fate of target sites that escaped high-grade restenosis (> or = 70% diameter narrowing) after percutaneous transluminal coronary angioplasty. Although favorable long-term prognosis after successful percutaneous transluminal coronary angioplasty is well documented, little is known about the stability of target sites. Long-term follow-up (mean 6.5 years, range 1.0 to 12.0) was performed in 693 patients with 948 narrowings (stenosis <70% in diameter at follow-up coronary angiography). Among them, 249 patients (36%) with 303 target sites received late follow-up coronary angiography. The relation of target sites to the culprit lesions for coronary events or newly developed angina was angiographically reviewed and progression/regression was also examined, focusing on the target sites. Regression was observed in 16 of 255 target sites in subjects with <50% stenosis and in 21 of 48 sites in the group with midgrade stenosis of 50% to 69% luminal narrowing (16 of 255, 6.3% vs 21 of 48, 43.8%, p <0.001). Progression was observed in 33 and 4 sites (33 of 255, 12.9% vs 4 of 48, 8.3%; p = NS) in each group, respectively. The rest remained within the same range of stenosis. Culprit lesions for 2 acute myocardial infarctions, 7 unstable anginas, and 17 newly developed anginas were related to the original target sites. Three lesions developed in the midgrade stenosis group. Those 26 lesions were a component of 8.6% of 303 angiographically confirmed sites and 2.7% of total target sites. Target sites that escape high-grade restenosis frequently regress and become stable plaques and rarely trigger coronary events.

Comparison of quantitative coronary angiography, intravascular ultrasound, and coronary pressure measurement to assess optimum stent deployment

BACKGROUND

Although intravascular ultrasound (IVUS) is the present standard for the evaluation of optimum stent deployment, this technique is expensive and not routinely feasible in most catheterization laboratories. Coronary pressure-derived myocardial fractional flow reserve (FFRmyo) is an easy, cheap, and rapidly obtainable index that is specific for the conductance of the epicardial coronary artery. In this study, we investigated the usefulness of coronary pressure measurement to predict optimum and suboptimum stent deployment.

METHODS AND RESULTS

In 30 patients, a Wiktor-i stent was implanted at different inflation pressures, starting at 6 atm and increasing step by step to 8, 10, 12, and 14 atm, if necessary. After every step, stent deployment was evaluated by quantitative coronary angiography (QCA), IVUS, and coronary pressure measurement. If any of the 3 techniques did not yield an optimum result, the next inflation was performed, and all 3 investigational modalities were repeated until optimum stent deployment was present by all of them or until the treating physician decided to accept the result. Optimum deployment according to QCA was finally achieved in 24 patients, according to IVUS in 17 patients, and also according to coronary pressure measurement in 17 patients. During the step-up, a total of 81 paired IVUS and coronary pressure measurements were performed, of which 91% yielded concordant results (ie, either an optimum or a suboptimum expansion of the stent by both techniques, P<0.00001). On the contrary, QCA showed a low concordance rate with IVUS and FFRmyo (48% and 46%, respectively).

CONCLUSIONS

In this study, using a coil stent, both IVUS and coronary pressure measurement were of similar value with respect to the assessment of optimum stent deployment. Therefore, coronary pressure measurement can be used as a cheap and rapid alternative to IVUS for that purpose.

Immediate results and late clinical outcomes after new CrossFlex coronary stent implantation

This study evaluates the safety and efficacy of the new CrossFlex stent in the treatment of native coronary artery disease. The CrossFlex stent is a flexible, balloon-expandable new device with an excellent flexibility, radial strength, conformability, and radio-opacity. Little data are available concerning the clinical and angiographic outcomes of this device. The CrossFlex stent was implanted in 209 consecutive patients with 226 lesions. Follow-up angiography was performed at 6 months, and clinical evaluation was undertaken at regular intervals after stent implantation. Procedural success was achieved in all lesions without in-hospital complications. Angiographic follow-up data were available in 153 of the 187 eligible lesions (follow-up rate, 82%), and the overall angiographic restenosis rate was 16.3%. Minimal lumen diameter immediately after stent placement was the only predictor of angiographic restenosis. Clinical follow-up was obtained in all patients at 10.5 +/- 5.2 months. There were 4 deaths (1 cardiac in origin, the others noncardiac in origin), and 1 nonfatal myocardial infarction (nonstented artery) during follow-up. Target lesion revascularization was required in 15 patients (7%), and the overall event-free survival rate (death, myocardial infarction, and repeat revascularization) was 87% at the end of the follow-up period. The CrossFlex stent is a safe and effective device with a high procedural success rate, and a favorable late clinical outcome for treatment of native coronary artery disease. Further randomized trials are needed to compare the CrossFlex stent with standard slotted-tube stents.

[Stent restenosis: therapy concepts and possibilities for prevention]

BACKGROUND

In-stent restenosis has become a significant problem for interventional cardiologists. Due to different pathogenic causes it remains unclear whether a uniform therapeutic regimen is appropriate.

TREATMENT

Redilatation has predominantly been used for the treatment of instent restenosis, however, in long and diffuse restenotic stents, long-term results are reported to be poor. Therefore, tissue-debulking techniques may have beneficial effects in complex cases of in-stent restenosis. The therapeutic benefit of intracoronary radiation, local drug delivery or gene transfer has not been evaluated so far.

PREVENTION

Therefore, prevention of the iatrogenic entity in-stent restenosis has become more important.

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.

First clinical experience with the premounted balloon-expandable serpentine stent: acute angiographic and intermediate-term clinical results

The beStent-Artist coronary stent is a newly developed, stainless steel coronary stent with a serpentine tubular design and terminal stent markers, premounted on a semicompliant balloon. During this pilot evaluation we aimed to test the acute clinical and angiographic results, short-term (30 days) and 6-month clinical results. A total of 57 stents were used to treat 43 lesions in 40 patients. Deployment strategy included predilatation, stent deployment, balloon repositioning to match the distal end of the balloon to the distal stent marker, and subsequent 12-14 atm postdilatation. There were two cases of stent dislodgment, but no procedural complications. In four cases, stent recrossing with another balloon was necessary. In two of these cases, distal dissections were observed and treated with another stent. The minimal lumen diameter (MLD) increased from 0.84+/0.52 mm at baseline to 2.7+/-0.62 mm at the end of the procedure (a corresponding decrease in diameter stenosis from 78.6 > 16.4 to 18.2+/-10.7%). The acute gain was 1.89+/-0.61mm. No adverse events occurred by 30 days. During six months, 7/40 (18.5%) of patients required target vessel revascularization due to in-stent restenosis. In summary, the premounted beStent-Artist can be delivered and deployed with favorable immediate results and high success rate with favorable long-term recurrent event rates.

Arterial stenting and balloon angioplasty in ostial atherosclerotic renovascular disease: a randomised trial

BACKGROUND

Percutaneous transluminal angioplasty (PTA) for ostial atherosclerotic renal-artery stenosis has poor results. Angioplasty with stent placement (PTAS) may be more effective. We undertook a randomised prospective study to compare PTA with PTAS in patients with ostial atherosclerotic renal-artery stenosis.

METHODS

Patients with ostial atherosclerotic renal-artery stenosis were assigned to receive PTA or PTAS. Secondary PTAS was allowed if PTA failed immediately or during 6 months' follow-up. Analysis was by intention to treat.

FINDINGS

42 patients were assigned PTA and 43 were assigned PTAS, but one patient in the PTAS group was excluded from the study. Primary success rate (<50% residual stenosis) of PTA was 57% (24 patients) compared with 88% (37 patients) for PTAS (difference between groups 31% [95% CI 12-50]). Complications were similar. At 6 months, the primary patency rate was 29% (12 patients) for PTA, and 75% (30 patients) for PTAS (46% [24-68]). Restenosis after a successful primary procedure occurred in 48% of patients for PTA and 14% for PTAS (34% [11-58]). 12 patients underwent secondary stenting for primary or late failure of PTA within the follow-up period: success was similar to that of primary PTAS. Evaluation based on intention to treat showed no difference in clinical results at six months for PTA or PTAS.

INTERPRETATION

PTAS is a better technique than PTA to achieve vessel patency in ostial atherosclerotic renal-artery stenosis. Primary PTAS and primary PTA plus PTAS as rescue therapy have similar outcomes. However, the burden of reintervention after PTA outweighs the potential saving in stents, so primary PTAS is a better approach to use.

Long-term prognosis in achieving a 'stent'like' result from balloon angioplasty: 8 years' clinical outcome

This study evaluated the long-term prognosis of optimal 'stent-like' results, suboptimal results and failure of balloon angioplasty. The clinical data of 108 patients were examined during 8 years following balloon angioplasty. Based on the angiographic results, the patients were divided into 3 groups: Group A (n=59), <25% residual stenosis (ie, optimal stent-like result); Group B (n=43), 26-50% residual stenosis or large dissection (ie, suboptimal result); and Group C (n=6), >50% residual stenosis or stenosis could not be crossed (ie, failed angioplasty). Restenosis occurred in 20 of 43 patients (46.5%) in Group B, but only in 18 of 59 patients (30.4%) in Group A. Achieving stent-like results following balloon angioplasty significantly reduced the incidence of restenosis. Kaplan-Meier curves at 8 years demonstrated a survival rate without serious cardiac events of 83% in patients with stent-like results compared with 58% in those with suboptimal results and 17% in those with failed balloon angioplasty. In conclusion, the major finding of this study is that achieving stent-like results following balloon angioplasty reduces the incidence of restenosis, and 8-year survival without serious cardiac events after balloon angioplasty is significantly better in patients who have a stent-like result.

Directional coronary atherectomy for the treatment of Palmaz-Schatz in-stent restenosis

Management of in-stent restenosis has become a significant challenge in interventional cardiology. The results of balloon angioplasty have been disappointing due to the high recurrence of restenosis at follow-up. Debulking of the restenotic tissue within the stents using directional coronary atherectomy (DCA) may offer a therapeutic advantage. We report the immediate clinical and angiographic outcomes and long-term clinical follow-up results of 45 patients (46 lesions), mean age 63+/-12 years, 73% men, with a mean reference diameter of 2.9+/-0.6 mm, treated with DCA for symptomatic Palmaz-Schatz in-stent restenosis. DCA was performed successfully in all 46 lesions and resulted in a postprocedural minimal luminal diameter of 2.7+/-0.7 mm and a residual diameter stenosis of 17+/-10%. There were no in-hospital deaths, Q-wave myocardial infarctions, or emergency coronary artery bypass surgeries. Four patients (9%) suffered a non-Q-wave myocardial infarction. Target lesion revascularization was 28.3% at a mean follow-up of 10+/-4.6 months. Kaplan-Meier event-free survival (freedom from death, myocardial infarction, and repeat target lesion revascularization) was 71.2% and 64.7% at 6 and 12 months after DCA, respectively. Thus, DCA is safe and efficacious for the treatment of Palmaz-Schatz in-stent restenosis. It results in a large postprocedural minimal luminal diameter and a low rate of both target lesion revascularization and combined major clinical events at follow-up.

Protection of side-branches in coronary lesions with a new stent design

Side-branches often complicate stenting of coronary lesions. We investigated a new stent, characterized by four wider cells in its center, which can be expanded up to 3.5 mm and which are meant to be placed over the ostium of a major side-branch. Forty-seven consecutive patients with lesions involving 48 side-branches received one side-branch stent each. Stent deployment was successful in all patients. Twenty-five side-branches needed additional treatment. Nineteen side-branches received a PTCA, and 6 additional side-branches were stented. Postinterventional CK-(creatine kinase) elevation was observed in 3 patients (6%). One additional patient was sent for CABG on the day of the procedure due to loss of a stent intended to be placed into the side-branch. The investigated stent proved to be a safe and effective tool to treat this complex subgroup of stenoses in the presence of favorably preserved flow in the side-branches, with a low incidence of periprocedural complications.

Initial and follow-up results of the ACS multi-link stent: a single center experience

The Palmaz-Schatz (PS) stent has effectively reduced restenosis; however its rigidity makes it sometimes difficult or impossible to deliver. The initial and follow-up outcomes with the ACS Multi-Link stent (deployed from April to November 1995) were evaluated in 70 patients (79 lesions): unplanned in 34% (abrupt closure 1%; threatened closure 5%; suboptimal results 28%) and planned in 66%. Three to six month follow-up angiograms were analyzable in 67 lesions; 96% procedural (in nine lesions PS stenting had failed) and 95% clinical success were achieved. In-hospital mortality was 1.4%. Myocardial infarction occurred in 2.9%, and subacute stent thrombosis in 1.4%. Stenting improved immediately the minimal luminal diameter (from 0.97+/-0.41 mm to 2.72+/-0.31 mm), but at 6 months it had decreased to 1.89+/-0.44 mm. Angiographic restenosis (<50% diameter stenosis) occurred in 11, a rate of 16.4%; target lesion revascularization (TLR) was required in six (re-PTCA in five or bypass surgery in one; 6/67=8.7%). Actuarial 1-2 year survival rate was 91%, 80% surviving free from major complications or need for TLR. We conclude that the ACS Multi-Link stent can be implanted in lesions unsuited for the PS stent with a high success rate, and an anticipated restenosis rate perhaps comparable to with the PS stent.

Intimal hyperplasia thickness at follow-up is independent of stent size: a serial intravascular ultrasound study

The purpose of this study was to determine whether the thickness of the intimal hyperplasia (IH) layer that accumulates within Palmaz-Schatz stents is dependent on stent size. Intravascular ultrasound (IVUS) and quantitative angiographic (QCA) studies were performed after stent implantation and at follow-up (5.4 +/- 3.8 months) in 161 patients with 177 lesions treated with 221 Palmaz-Schatz stents. Stent and lumen cross-sectional area (CSA) were measured. IH CSA and thickness at follow-up were calculated and compared with stent CSA and circumference. Maximum IH CSA and thickness were measured at the smallest follow-up lumen CSA; mean IH CSA and thickness was averaged over the length of the stent. Maximum IH CSA measured 4.8 +/- 2.4 mm2, and mean IH CSA measured 2.8 +/- 2.2 mm2. Maximum IH thickness (at the smallest follow-up lumen CSA) measured 0.60 +/- 0.36 mm, and mean IH thickness (over the length of the stent) measured 0.30 +/- 0.19 mm. There was a weak, but significant correlation between mean and maximum IH CSA versus stent CSA (r = 0.215, p <0.0001 and r = 0.355, p <0.0001, respectively). However, there was no correlation between mean or maximum IH thickness versus stent CSA (r = 0.018, p = 0.643 and r = 0.056, p = 0.463, respectively) or stent circumference (r = 0.002, p = 0.956 and r = 0.069, p = 0.361, respectively). IH thickness was found to be independent of the stent size. This explains the known higher frequency of restenosis in smaller stents compared with larger stents.

Post-mortem examination after cardiac surgery

Following a recent enquiry into surgery at a paediatric cardiac centre in England, there will be substantial changes in the way that the success and failure of surgical procedures will be monitored and investigated. Post-mortem examinations on patients dying after cardiac surgery are likely to be performed and reported in more detail. This review describes the protocol that we have developed and summarizes recent clinical and pathological studies that have increased our understanding of postoperative pathophysiology. Close attention should be paid to the history, particularly the operation note. Cardiac failure is the commonest cause of death. We believe this is a clinicopathological diagnosis and provide definitions of preoperative and perioperative cardiac failure. Haemorrhage, stroke, pulmonary emboli and infection are other important causes of death. Methods of dissection are suggested for bypass grafts and valve replacements. Two recent studies show that the post-mortem examination provides answers to most clinical questions and reveals an unexpected cause of death in 10-15% of patients. There are limitations however: an incomplete or indeterminate cause of death is found in 14-25% of patients, most commonly sudden clinically unexplained death or clinically unexplained cardiac failure soon after surgery.

Late coronary artery stenting in patients with acute myocardial infarction

BACKGROUND

The safety and efficacy of late coronary artery stenting of the infarct-related artery after acute infarction has not been evaluated previously.

METHODS AND RESULTS

Coronary artery stenting was performed in 117 consecutive patients with acute infarction who were receiving ticlopidine/aspirin regimen without coumarin. There were 97 men and 18 women, aged 58+/-11 (mean +/- SD) years. A total of 136 Palmaz-Schatz stents were successfully implanted in 130 lesions 15+/-8 days after acute myocardial infarction (median 9 days) in 115 of 117 (98%) patients. The minimal luminal diameter (MLD) increased from 0.66+/-0.46 to 3.14+/-0.53 mm (P< .001), with an acute gain of 2.49+/-0.61 mm. One patient had acute thrombosis requiring further stenting and another patient received emergency bypass surgery. There was no subacute thrombosis or other complications. During a follow-up duration of 14+/-3 months, 2 patients had angina pectoris develop and 1 died suddenly. Sixty-two patients underwent a follow-up coronary angiography 195+/-36 days after stenting. Restenosis was noted in 8 patients (13%); the MLD was 2.19+/-0.73 mm, the late loss was 0.96+/-0.65 mm (P< .001), the loss index was 0.39+/-0.28, and the net gain was 1.56+/-0.79 mm (P< .001). The angiographic left ventricular ejection fraction increased from 47%+/-12% to 55%+/-12% (P< .001).

CONCLUSIONS

Late coronary stenting of the infarct-related artery in patients with acute myocardial infarction is a safe and effective late reperfusion therapy and may be beneficial to the patients.

Accuracy of single-photon emission computed tomography myocardial perfusion imaging in patients with stents in native coronary arteries

Strategies to noninvasively evaluate patients after coronary stenting have not been evaluated. To determine the accuracy of single-photon emission computed tomography (SPECT) myocardial perfusion imaging in patients after coronary stenting, 209 patients who had undergone stenting followed by late stress SPECT myocardial perfusion imaging were evaluated. Quantitative coronary angiography was performed in 33 patients following SPECT imaging. SPECT restenosis was defined as a reversible or fixed defect within the stented vascular territory. Angiographic restenosis was examined using 2 definitions: total area narrowing > or =50% or > or =70% of the stent site or stented artery. The SPECT and angiographic findings were concordant in 22 of 33 stented vascular territories using the 50% definition of restenosis and in 29 of 33 stented territories using the 70% definition. Use of the 70% definition of restenosis resulted in improved accuracy of SPECT to detect a significant stenosis in the stented artery. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SPECT were 95%, 73%, 88%, 89%, and 88% respectively. In patients with positive SPECT scans, the most significant stenosis in the stented artery was outside the stent site in 50% of cases. SPECT imaging appears to be accurate to predict significant stenosis in the stented artery, although the most severe stenosis is frequently distant from the stent site.

Sustained benefit of stenting chronic coronary occlusion: long-term clinical follow-up of the Stenting in Chronic Coronary Occlusion (SICCO) study

OBJECTIVES

This study assessed the long-term clinical outcome of stenting chronic occlusions.

BACKGROUND

In the Stenting in Chronic Coronary Occlusion (SICCO) study, patients were randomized to additional stent implantation (n = 58) or not (n = 59) after successful recanalization and dilation of a chronic coronary occlusion. Palmaz-Schatz stents were used with full anticoagulation. The previously published 6-month angiographic follow-up results showed reduction of the restenosis rate from 74% to 32%.

METHODS

The primary end point was the occurrence of major adverse cardiac events (cardiac death, lesion-related acute myocardial infarction, repeat lesion-related revascularization or angiographic documentation of reocclusion).

RESULTS

Late clinical follow-up was obtained in all patients at 33 +/- 6 months. Major adverse cardiac events occurred in 14 patients (24.1%) in the stent group compared with 35 patients (59.3%) in the percutaneous transluminal coronary angioplasty (PTCA) group (odds ratio 0.22, 95% confidence interval 0.10 to 0.49, p = 0.0002). Target vessel revascularization (including failed PTCA attempts) was performed in 24% of the stent group and in 53% of the PTCA group (p = 0.002). There were no events in the stent group after 8 months, whereas events continued to occur in the PTCA group. By multivariate analysis, allocation to the PTCA group, left anterior descending coronary artery lesion and lesion length were significantly related to the development of major adverse cardiac events.

CONCLUSIONS

These data demonstrate the long-term safety and clinical benefit of stenting recanalized chronic occlusions. There is a continued risk of late clinical events related to nonstented lesions. Implantation of an intracoronary stent should therefore be considered after successful opening of a chronic coronary occlusion.

Coronary stenting in the elderly: longitudinal results in a wide spectrum of patients treated with a new and more practical approach

One hundred-twelve intracoronary stents (83 Palmaz-Schatz, 25 biliary, and 4 Gianturco-Roubin) were placed in 87 (51.7% male) patients aged > or = 70 years (70-93; mean 76.1) during a 1-year period. All stents were deployed using high-pressure inflation (mean 17.4 +/- 2 atm) without intravascular ultrasound. All patients received antiplatelet therapy with aspirin and ticlopidine. Seven patients additionally received warfarin at the physician's discretion. No patient was excluded from analysis regardless of presentation (40% acute myocardial infarction and 12.6% bailout) or complication. There were four deaths and two target vessel reinterventions in-hospital. One reintervention (a bailout) developed a non-Q-wave myocardial infarction. Bleeding, vascular complications, and length of stay were all greater for the warfarin group. The event-free survival rate was 83.9%, at an average of 8.6 months follow-up. A wide range of elderly patients can thus undergo stenting without intravascular ultrasound, usually without warfarin, yielding results comparable to those with more standard therapy in select populations.

Assessment of coronary artery patency after stent placement using magnetic resonance angiography

The ability to noninvasively assess the patency of coronary stents would represent a significant advance. We evaluated the safety and ability of two-dimensional coronary MR angiography in imaging stents and suggesting patency. Coronary MR angiography of 26 coronary stents (Palmaz-Schatz) was performed in 16 patients 39 to 73 years of age. Studies were performed between 2 and 4 months after stent placement. All patients were symptom free at the time of imaging. Coronary MR angiography was performed with a commercial 1.5-T MR imager using an electrocardiographically gated pulse sequence with breath-holding. Images were obtained in mid-diastole with and without fat suppression. Image artifacts caused by the metal in the stents were clearly visualized in all 26 stents (100% sensitivity for stent detection). Arterial flow signal was seen in the coronary artery or graft distal to the stent in 25 of 26 cases (96%). All patients, except for the one in which distal flow could not be seen, remained symptom free for >2 years. The distribution of stent locations was as follows: 10 in the right coronary artery (RCA), 10 in the left anterior descending coronary artery (LAD), 2 in the left circumflex coronary artery, and 4 in saphenous vein grafts (SVGs) to RCA. One patient had 2 RCA and 2 LAD stents, one had 3 RCA and 1 LAD stents, one had 3 SVG stents, and two had double RCA stents. Coronary MR angiography is safe for noninvasive imaging of coronary stents, and in the proper clinical setting, it can be used to help suggest patency.

Remodeling of in-stent neointima, which became thinner and transparent over 3 years: serial angiographic and angioscopic follow-up

BACKGROUND

Recently, it has been reported that the luminal diameter shows phasic changes after stenting: the progression of luminal narrowing followed by its regression. To elucidate the mechanisms involved in the phasic changes in luminal diameter after stenting, we examined the changes in neointimal thickness and the appearance of neointima by a series of angiographic and angioscopic observations for 3 years after stent implantation.

METHODS AND RESULTS

In 12 patients who received a Wiktor coronary stent, serial angiographic and angioscopic examinations were performed immediately, 2 to 4 weeks, 3 months, 6 months, and 3 years after the stenting without repetition of angioplasty. Neointimal thickness was determined by angiography as the difference between stent and luminal diameters. The angioscopic appearance of neointima over the stent was classified as transparent or nontransparent according to the visibility of the majority of the stent. Neointimal thickness increased significantly at 3 months (0.75+/-0.32 mm) without further changes at 6 months (0.74+/-0.32 mm). Thereafter, however, it decreased significantly over 3 years (0.51+/-0.26 mm). The angioscopic appearance was classified as transparent in 8 patients (100) immediately after stenting, 6 patients (100%) at 2 to 4 weeks, 2 patients (17%) at 3 months, 2 patients (20%) at 6 months, and 7 patients (58%) at 3 years.

CONCLUSIONS

The neointima became thick and nontransparent until 6 months and then became thin and transparent by 3 years. We conclude that neointimal remodeling exists after stenting and plays a major role in the alteration of coronary luminal diameter after stenting.

Midterm results after minimally invasive coronary surgery (LAST operation)

BACKGROUND

Our experience with a left internal thoracic artery graft to the left anterior descending artery via a left anterior small thoracotomy is reviewed to evaluate midterm results.

METHODS

From November 1994 to April 1997, four hundred sixty patients were scheduled to undergo a left internal thoracic artery graft to the left anterior descending coronary artery via a left anterior small thoracotomy; 26 of these patients (5.7%) were converted and 434 of them had the operation. Two hundred fourteen patients (49.3%) had isolated disease of the left anterior descending artery, and 220 patients (50.7%) had multiple vessel disease. A sufficient length of the left internal thoracic artery was harvested to reach the left anterior descending artery.

RESULTS

Three hundred nine patients (71.2%) underwent extubation by hour 2. Mean intensive care unit stay was 4.2 +/- 4.5 hours; mean postoperative hospital stay was 66 +/- 29 hours; the 30-day mortality rate was 1.1%; the late mortality rate was 1.4%. Eighteen patients underwent reoperation early (< or = 30 days), and eight patients underwent reoperation late (> 30 days) because of conduit/anastomotic malfunction. Four patients underwent reoperation with patent anastomosis for progression of disease (n = 3) or pericarditis (n = 1). Three patients had a percutaneous transluminal coronary angioplasty. Cumulating angiographic and stress Doppler flow assessment results, a patent anastomosis was obtained in 417 patients and a nonrestrictive anastomosis in 404 patients. Twenty-nine months after surgery, survival was 97.1% +/- 0.7% (95% confidence interval 90.5% to 100%) and event-free survival 89.4% +/- 1.2% (95% confidence interval 78.2% to 100%). In the last 190 patients, with our increased experience and better instruments, we obtained a patent anastomosis in 188 patients (98.9%) and a nonrestrictive anastomosis in 185 (97.4%).

CONCLUSIONS

Left anterior small thoracotomy gives acceptable midterm results. Incidence of patent and nonrestrictive anastomoses was satisfactory, especially in the most recent part of our experience, when the learning curve ended.