Side Branch Compromise Research Articles

Carina shift as a mechanism for side-branch compromise following main vessel intervention: insights from three-dimensional optical coherence tomography.

Three-dimensional rendering of optical coherence tomography (OCT) images is a method that can be used for providing additive information for assessing the result of percutaneous coronary intervention (PCI), especially in complex lesions such as in bifurcations (1). While plaque shift has been considered the main underlying mechanism for side-branch compromise after stenting (2), new theories challenge the role of plaque shift and suggest carina shift to be a major contributor (3-6). We present a case were on-line three-dimensional OCT was used to demonstrate the role of carina shift in side-branch pinching, following main vessel intervention.

Acute and Long-Term Angiographic Outcomes of Side Branch Stenosis after Randomized Treatment of Zotarolimus-, Sirolimus-, and Paclitaxel-Eluting Stent for Coronary Artery Stenosis

This was designed to assess the outcomes of side branch (SB) stenosis after implantation of three drug-eluting stents (DES). From 2,645 patients in the ZEST (Comparison of the Efficacy and Safety of Zotarolimus-Eluting Stent with Sirolimus-Eluting and PacliTaxel-Eluting Stent for Coronary Lesions) Trial, 788 patients had 923 bifurcation lesions with SB ≥ 1.5 mm were included. SB was treated in 150 lesions, including 35 (3.8%) receiving SB stenting. Of untreated SB with baseline stenosis < 50%, the incidences of periprocedural SB compromise was similar in the zotarolimus (15.8%), sirolimus (17.2%), and paclitaxel (16.6%) stent groups (P = 0.92). At follow-up angiography, delayed SB compromise occurred in 13.9%, 3.2%, and 9.4% (P = 0.010) of these groups. When classified into four groups (< 50%, 50%-70%, 70%-99%, and 100%), 9.0% of untreated SB were worsened, whereas improvement and stationary were observed in 9.6% and 81.4%. In a multivariable logistic regression model, main branch (MB) stenosis at follow-up (%) was the only independent predictor of SB stenosis worsening (odds ratio, 1.03; 95% confidence interval, 1.01-1.04; P < 0.001). After MB stenting in bifurcation lesions, a minority of SB appears to worsen. DES with strong anti-restenotic efficacy may help maintain SB patency.

Preintervention Angiographic and Intravascular Ultrasound Predictors for Side Branch Compromise After a Single-Stent Crossover Technique

A single stent crossover technique is the most common approach to treating bifurcation lesions. In 90 bifurcation lesions with side branch (SB) angiographic diameter stenosis <75%, we assessed preintervention intravascular ultrasound (IVUS; of main branch [MB] and SB) predictors for SB compromise (fractional flow reserve [FFR] <0.80) after a single stent crossover. Minimal lumen area (MLA) was measured within each of 4 segments (MB just distal to the carina, polygon of confluence, MB just proximal to polygon of confluence, and SB ostium). All lesions showed Thrombolysis In Myocardial Infarction grade 3 flow in the SB after MB stenting. Although angiographic diameter stenosis at the SB ostium increased from 26 ± 15% before the procedure to 36 ± 21% after stenting (p = 0.001), FFR <0.80 was observed in only 16 patients (18%). Negative remodeling (remodeling index <1) was seen in 83 (92%) lesions but did not correlate with FFR after stenting. Independent predictors for FFR after stenting were maximal balloon pressure (p = 0.002) and MLA of SB ostium before percutaneous coronary intervention (p <0.001), MLA within the MB just distal to the carina (p = 0.025), and plaque burden at the SB ostium before percutaneous coronary intervention (p = 0.005), but not angiographic poststenting diameter stenosis or minimal lumen diameter. For prediction of FFR <0.80 after percutaneous coronary intervention, the best cutoff of MLA within the SB ostium before percutaneous coronary intervention was 2.4 mm(2) (sensitivity 94%, specificity 69%). Also, the cutoff of plaque burden within the SB ostium before percutaneous coronary intervention was ≥51% (sensitivity 75%, specificity 71%). In 67 lesions with an MLA ≥2.4 mm(2) or plaque burden <50% before percutaneous coronary intervention, 63 (94%) showed FFR ≥0.80. However, FFR <0.80 was seen in only 12 (52%) of 23 lesions with an MLA <2.4 mm(2) and plaque burden ≥50%. In conclusion, there do not appear to be reliable IVUS predictors of functional SB compromise after crossover stenting.

In‐hospital and nine‐month outcomes among patients with coronary lesions involving a side branch and treated with bare metal stents

The optimal management of coronary lesions involving side branches is not known. New devices are being developed for dedicated bifurcation stenting or improved side branch access or protection. Several of these devices are bare-metal stent (BMS) platforms. The risk of side branch compromise and outcome after standard BMS is not known. We evaluated the frequency of side branch involvement and the rate of side branch compromise in a retrospective analysis of 1,440 patients from three pooled historical BMS clinical trials. The impact of side branch compromise on in-hospital and nine-month clinical outcomes was assessed. Side branches >2 mm in diameter were present within the stented segment in 39% of treated lesions. Compromise of a side branch occurred in 27% of 1,440 lesions, including 22% of side branches that were not diseased prior to stenting. Compromise was associated with increased in-hospital MI (13.5% vs. 7.6%, P = 0.001), a trend for increased nine-month clinically driven target vessel revascularization (TVR, 17.4% vs. 13.2%, P = 0.058), and increased nine-month target vessel failure (composite of cardiac death, target vessel MI or TVR, 29.7% vs. 20.2%, P < 0.001). At least moderate-sized side branches are involved frequently in lesions enrolled in routine clinical trials. Unexpected compromise of these side branches is common and is associated with increased in-hospital and nine-month adverse outcomes.

Coronary stent length predicts PCI-induced cardiac myonecrosis

Myocardial necrosis complicates one-third of percutaneous coronary intervention (PCI, MI4a) and may adversely affect the outcome. We assessed the angiographic variables associated with MI4a that may help to identify those at highest risk. Cardiac troponin-I (cTnI) was measured after PCI in 243 patients undergoing elective PCI. Patients were grouped according to post-procedure cTnI result: minor or no elevation (<0.1 ng/ml), PCI-related MI4a (0.1 to <0.78 ng/ml) and WHO defined MI by the Troponin-I Ultra method (>or=0.78 ng/ml). Angiographic variables were analyzed in blinded manner and correlated with cTnI rise. Minor or no cTnI elevation after PCI occurred in 116 of 243 (48%) patients, MI4a in 65 of 243 (27%) and WHO defined MI in 62 of 243 (25%). Independent predictors of MI4a included stent length [odds ratio (OR) 1.04 per mm; P=0.0015], X-ray screening time (OR 1.05 per minute; P=0.016) and procedural chest pain requiring opiates (OR 7.92; P=0.00066). The stenting of proximal vessel segments with fewer collaterals (large myocardial area at risk), diminished myocardial perfusion (P=0.0065) and side branch compromise were associated with cTnI elevation. Clinical events were more frequent following MI4a (9.4 vs. 3.4%, P=0.07). These data show that cTnI release after elective PCI is predominantly related to stent length. Minimizing the stent length deployed may reduce the cTnI release and improve prognosis.

Evaluation of the effects of everolimus‐eluting and paclitaxel‐eluting stents on target lesions with jailed side branches: 2‐year results from the SPIRIT III randomized trial

To evaluate whether an everolimus-eluting stent (EES) with thinner stent struts and polymer results in less periprocedural myonecrosis and adverse outcomes. Higher periprocedural myocardial infarction (MI) rates have been reported with the TAXUS® EXPRESS(2) paclitaxel-eluting stent (PES) compared to the bare metal EXPRESS(2)® stent due to more frequent side branch compromise, presumably attributable to the thickness of the stent/polymer on the PES. In the SPIRIT III trial, we identified 113 patients in the XIENCE V® EES group and 63 patients in the TAXUS EXPRESS(2) PES group who met the criteria of having a lesion with a jailed side branch (<2 mm diameter, and <50% stenosis). Two-year clinical outcomes were evaluated. A periprocedural increase in Creatine Kinase-MB >1× upper normal level occurred in 9.0% of EES compared to 29.7% of PES patients with jailed side branches, P = 0.01. Through 2 years, major adverse cardiac events (MACE; cardiac death, MI, or target lesion revascularization [TLR]) occurred in 6.8% of EES and 19.0% of PES jailed side branch patients (P = 0.03), with numerically lower rates of MI (2.9% vs. 10.3%, P = 0.07) and TLR (3.9% vs. 10.3%, P = 0.17) in the EES group, with comparable rates of cardiac death (1.9% vs. 1.7%, P = 1.00). In this post-hoc analysis of the SPIRIT III RCT, patients undergoing stenting of target lesions with jailed side branches with the thin strut and polymer XIENCE V EES compared to the thicker strut TAXUS PES had lower rates of MACE through 2 years due to fewer MIs and TLRs. © 2010 Wiley-Liss, Inc.

Jailed balloon protection: a new technique to avoid acute side-branch occlusion during provisional stenting of bifurcated lesions. Bench test report and first clinical experience

Provisional stenting with drug-eluting-stents is actually adopted to treat most of bifurcated lesions. A major drawback of this technique is the risk of side-branch (SB) closure after main vessel (MV) stenting. We set-up, and bench tested, a novel technique for SB protection based on the placement of a balloon in the SB during MV stenting. The uninflated balloon, which remains jailed under the stent struts, serves to reduce both carina and plaque shifts due to its SB ostium spatial occupation. If SB flow is preserved after MV stenting, the jailed balloon is removed uninflated. If the SB becomes occluded after MV stenting, the jailed balloon may either be used as a marker and a favourable angle modifier to facilitate rewiring or can be dilated to try to restore SB flow. SB rewiring and kissing balloon inflation must be performed to correct stent deformation or malapposition. This novel technique has been successfully adopted in 20 patients with complex (55% unprotected left main, 85% Medina 1,1,1 lesions) true bifurcated lesions undergoing drug-eluting-stent implantation. The jailed balloon protection is a novel technique aimed at improving SB protection during provisional stenting of bifurcated lesions considered at high risk of SB compromise after MV stenting.

The Carina Angle—New Geometrical Parameter Associated with Periprocedural Side Branch Compromise and the Long‐Term Results in Coronary Bifurcation Lesions with Main Vessel Stenting Only

The two main problems unresolved in coronary bifurcation stenting are periprocedural side branch compromise and higher restenosis at long term. The purpose of this study is to reveal the link between periprocedural side branch compromise and long-term results after main vessel stenting only in coronary bifurcations. Eighty-four patients formed the study population. The inclusion criteria were good-quality angiograms, with maximal between-branch angle opening, no overlap, permitting accurate angiographic analysis. Carina angle (alpha)-the distal angle between main vessel (MV) before bifurcation and side branch (SB)-was measured pre- and poststenting. Clinical follow-up 9-12 months was obtained with coronary angiography if needed. The patient population was high-risk with 33% diabetics and 84% two- and three-vessel disease. Ninety-five stents were implanted in 92 lesions, with three T-stenting cases. Drug-eluting stents were implanted in 54%. Kissing-balloon (KBI) or sequential inflation was performed in 35%. SB functional closure occurred in 17.4%, with independent predictors alpha < 40 degrees and diameter ratio MB/SB >1.22. After 12+/-4 months there were five myocardial infarctions (6%) and 13 (15%) target lesion revascularization procedures. Independent predictors of major cardiovascular events were carina angle <40 degrees , MB lesion length >8 mm, negative change of between-branch angle, DES usage, and KBI. Smaller carina angle with straightening of MV-main branch from stent implantation in coronary bifurcations predicted higher SB compromise, restenosis, and MACE rates during follow-up of 1 year.

Recanalization Results After Intracranial Stenting of Atherosclerotic Stenoses

The purpose of this investigation was to provide a detailed description of the angiographic results after stenting of high-grade intracranial stenosis using balloon-expandable stents. Forty consecutive patients with symptomatic atherosclerotic intracranial stenosis >50% received endovascular treatment by placement of balloon-expandable stents using the concept of slight underdilation and strict avoidance of overdilation. Intra-arterial digital subtraction angiography images before and after stenting in the same projection were reviewed for pre- and post-therapeutic measurement of the degree of stenosis and evaluation of morphologic criteria like plaque coverage, stent apposition, patency of side branches, and signs of dissection or vasospasm. Stenting decreased the mean percentage stenosis from 76.2 (WASID criteria) to 20.8%. Residual stenosis ranged from 0 to 55% with residual stenosis >50% in two of 40 cases. Technical success rate was 95%. There were no major vessel complications, but minor abnormalities like incomplete stent apposition (8/40) or plaque coverage (7/40), incomplete filling of side branches (13/40), and minor dissections after stenting (2/40) were seen. One case with incomplete stent apposition and two cases with side branch compromise were associated with clinical symptoms. In conclusion, intracranial stenting with slight underdilation avoided major vessel complication and created reliable luminal gain. Suboptimal recanalization results were frequently detected and may be the source of neurological complications in individual cases.

Clinical Verification of a Theory for Predicting Side Branch Stenosis after Main Vessel Stenting in Coronary Bifurcation Lesions

To verify in a clinical scenario a theory for predicting side branch (SB) stenosis after main vessel stent implantation in coronary bifurcation lesions. Many unresolved issues remain regarding SB compromise when the parent vessel is stented. Bifurcation lesions (all Medina types) were subjected to angiographic analysis to determine the angle, defined as alpha, between the axes of the parent vessel and the SB. Using the prediction that the percent diameter stenosis (%DS) is equal to the cosine of angle alpha and relating it to a formula to determine the minimal lumen diameter (MLD) led to the following equation: MLD = ds x (1 -cos alpha); ds refers to the diameter of the SB. The predicted and observed SB stenosis values following angiography were compared. Fifty-two patients with 57 lesions were included in the analysis. Patient demographics and characteristics were similar to those in previous studies. There was a high coefficient of determination between the predicted and observed values of %DS (r(2)= 0.82, P < 0.001) and MLD (r(2)= 0.86, P < 0.001). We determined a cutoff value of 70% for predicted %DS for SB closure. When using multivariate regression analysis, the only predictor of SB ostial stenosis after stenting was alpha angle, whereas the predictors of MLD included the angle alpha and the RVD of the SB. Our analysis shows that the most powerful independent predictor of SB compromise is a new variable angle alpha.

Aortic Dissection With Aortic Side Branch Compromise: Impact of Malperfusion on Patient Outcome

The purpose of this study was to review the management and clinical outcome of patients with aortic dissection and symptomatic or asymptomatic aortic branch compromise. We identified 104 patients (30.7%) with aortic branch compromise from a group of 339 patients who underwent surgical management of aortic dissection from January 1971 to May 2003. Patients were divided into 2 groups: symptomatic and asymptomatic aortic branch compromise, based on the presence or absence of cerebral, extremity, spinal, renal, and visceral ischemia. Clinical data and outcome were reviewed and compared in both groups. There were 74 male (77%) and 30 female patients with a mean age of 58.5 (range, 23-81) years. Aortic dissection was classified as Stanford type A in 58.7%, acute in 58.7%, and was associated with asymptomatic aortic branch compromise in 44 patients (42.3%) and symptomatic aortic branch compromise in 60 patients (57.7%). Asymptomatic and symptomatic aortic branch compromise, respectively, were distributed in the extremity (30 and 33), carotid (5 and 4), renal (21 and 28), visceral (13 and 8), and spinal (0 and 5) arteries. In the asymptomatic aortic branch compromise group, all patients had aortic graft replacement, and 9 had branch reconstructions. In the symptomatic aortic branch compromise group, treatment was aortic graft replacement (48), open fenestration (6), and endovascular treatment (6). Operative mortality rate was 9.1% (4 of 44) in the asymptomatic and 38.3% (23 of 60) in the symptomatic aortic branch compromise during the 30-year study period (P = .001), decreasing from 35.1% (20 of 57) prior to 1990 to 14.9% (7 of 47) since 1990 (P = .04). In the symptomatic group, operative mortality decreased from 56.7% (17 of 30) to 20% (6 of 30) in the same interval (P = .003). Patients treated in both treatment eras were similar except for less aortic graft replacements and more aortic fenestrations and direct branch reconstructions since 1990. Multivariate analysis revealed symptomatic aortic branch compromise group, treatment prior to 1990, Marfan syndrome, age greater than 70 years, and postoperative complications to be independently associated with increased operative mortality. Asymptomatic aortic branch compromise was not associated with increased operative mortality, but organ malperfusion was an independent risk factor for operative death. The operative mortality significantly decreased since 1990, mostly because of changes in our surgical approach, with less aortic graft replacements and more complication-directed procedures.

The Impact of Surgical and Percutaneous Coronary Revascularization on the Cardiac Myocyte

Re-establishing coronary blood flow to a segment of myocardium suffering from cessation or diminution of flow, either with surgical or percutaneous approaches, may be complicated by injury to the myocardium. During surgical revascularization with coronary artery bypass grafting (CABG), aortic cross-clamping and subsequent reduction in oxygen transport to the myocardium may result in cardiac myocyte injury and myonecrosis. This injury can be compounded if protection of the myocardium using myocardial protective strategies is not adequate. Ischemia/reperfusion cellular alterations may contribute to this injury as well. Percutaneous coronary interventions (PCI) are also associated with myonecrosis resulting from side branch compromise, distal embolization of debris, and plugging of the microcirculation, as well as ischemia/reperfusion injury. Intracoronary filtering devices have not been shown to improve outcomes associated with such complications. Which revascularization strategy is associated with superior outcomes and less cardiac myocyte necrosis is an area of continuing controversy.

Percutaneous coronary intervention for major bifurcation lesions using the simple approach: risk of myocardial infarction

Recent data has suggested that simple (main vessel only) stenting is the preferred approach for patients with bifurcation lesions. We sought to determine the feasibility and outcomes of this approach in a year long inclusive registry. From August, 2004-2005, a registry of 1,600 consecutive patients undergoing PCI was reviewed. Patients undergoing PCI for major bifurcation lesions--> or =70% stenosis in a major (> or =2 mm) side branch and/or main vessel--were identified by review of the angiograms. Angiographic, clinical and treatment predictors of final SB compromise (> or =70% stenosis and/or less than TIMI 3 final flow) were identified. Hundred and fifty eight patients who underwent initial stenting of the main vessel with subsequent rescue of the side branch if SB compromise occurred ("Provisional Main Vessel Stenting") comprised the analysis population. Permanent SB compromise occurred in 16% of patients and was associated with an increased risk of large periprocedural MI and renal failure. Independent predictors of permanent SB compromise were lack of pre-PCI beta blockers, presence of diabetes mellitus, main vessel eccentric lesion and small SB vessel diameter. Among unselected patients with major bifurcation lesions undergoing a "simple" stenting approach, there is a significant rate of large periprocedural infarction and side branch compromise.

Issue Highlights

HomeCirculationVol. 114, No. 7Issue Highlights Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBIssue Highlights Originally published15 Aug 2006https://doi.org/10.1161/circ.114.7.615Circulation. 2006;114:615ORTHOSTATIC HYPOTENSION PREDICTS MORTALITY IN MIDDLE-AGED ADULTS: THE ATHEROSCLEROSIS RISK IN COMMUNITIES (ARIC) STUDY, by Rose et al.Orthostatic hypotension, defined as a decrease of 20 mm Hg of systolic blood pressure or 10 mm Hg diastolic blood pressure with standing, occurs in about 5% of people in the community. This condition predicts adverse effects in older, frail populations, but its importance in middle-aged groups is less well defined. Investigators from the Atherosclerosis Risk in Communities (ARIC) Study compared 674 middle-aged individuals with orthostatic hypotension and 128 people without the condition. They assessed whether orthostatic hypotension predicted risk of death over 13 years of follow-up, after adjusting for other important risk factors. The findings suggest that orthostatic hypotension might be a new important risk factor with considerable prognostic importance. See p 630.LOCAL CONTROLLED INTRAMYOCARDIAL DELIVERY OF PLATELET-DERIVED GROWTH FACTOR IMPROVES POSTINFARCTION VENTRICULAR FUNCTION WITHOUT PULMONARY TOXICITY, by Hsieh et al.Although there is evidence that platelet-derived growth factor (PDGF) can protect the myocardium from ischemic injury, PDGF also has the potential to cause pulmonary hypertension. Hsieh et al tested the ability of self-assembling peptide nanofibers to deliver PDGF to the myocardium. In rats subjected to myocardial infarction by coronary artery ligation, injection at the time of ligation of PDGF via nanofibers reduced infarct size by over 50% and resulted in improved left ventricular size and function from 1 day to 3 months after infarction. There was no evidence of pulmonary hypertension or pulmonary artery remodeling. This experiment suggests that nanofibers can be used to selectively deliver a therapeutic agent to the myocardium. See p 637.PLAQUE VOLUME AND OCCURRENCE AND LOCATION OF PERIPROCEDURAL MYOCARDIAL NECROSIS AFTER PERCUTANEOUS CORONARY INTERVENTION: INSIGHTS FROM DELAYED-ENHANCEMENT MAGNETIC RESONANCE IMAGING, THROMBOLYSIS IN MYOCARDIAL INFARCTION MYOCARDIAL PERFUSION GRADE ANALYSIS AND INTRAVASCULAR ULTRASOUND, by Porto et al.In this issue of Circulation, Porto and colleagues systematically studied the mechanism of myonecrosis during percutaneous coronary intervention of native coronary arteries using angiographic analysis, intravascular ultrasound, and delayed-enhancement magnetic resonance imaging. Two distinct patterns of myonecrosis were observed: 1) “adjacent” to the stent and related to side branch compromise; and 2) “distal” or downstream from the stent and associated with significantly greater reduction in plaque volume and closed microvasculature consistent with distal embolization. The findings of Porto et al have important implications for efforts to minimize procedural myonecrosis, strongly suggesting that consideration of side branch anatomy, stent design, and/or use of distal protection devices during extensive coronary stenting will be required to optimize clinical outcomes. See p 662.Visit http://circ.ahajournals.org:Cardiology Patient PageCarotid Artery Disease. See p e244.Images in Cardiovascular MedicineA Rare Form of Midventricular Tako-Tsubo After Emotional Stress Followed up by Magnetic Resonance Imaging. See p e248.Spontaneous Left Atrial Dissection and Hemotoma Mimicking a Cardiac Tumor: Findings From Echocardiography, Cardiac Computed Tomography, Magnetic Resonance Imaging, and Pathology. See p e249.Wall-Motion Abnormalities Detection With Contrast Enhanced Multislice Computed Tomography. See p e251. Download figureDownload PowerPointBook ReviewC-Reactive Protein and Cardiovascular Disease. See p e253.CorrespondenceSee p e255. Previous Back to top Next FiguresReferencesRelatedDetails August 15, 2006Vol 114, Issue 7 Advertisement Article InformationMetrics https://doi.org/10.1161/circ.114.7.615 Originally publishedAugust 15, 2006 PDF download Advertisement

Troponin T elevation after successful directional atherectomy.

The incidence and correlates of postinterventional cardiac troponin T (cTnT) elevation have not been evaluated in patients with successful directional atherectomy (DCA). Total creatine kinase (CK) activity, CK-MB mass concentrations and cTnT levels were measured in 36 patients before, and serially 4, 24, 48 and 72 hours after successful DCA. Patients were followed for death, Q-wave infarction, need for emergency bypass surgery, periprocedural vascular complications (transient in-lab vessel closure, side branch compromise, large dissection), and non-Q-wave infarction on ECG. Patients were followed for clinical outcomes and angiographic restenosis for 6 months. Vascular correlates were studied by coronary angiography and intravascular ultrasound before, immediately after and 4 hours after elective and successful DCA. 25 patients (69.4%) had elevated levels of cTnT, whereas CK-MB mass > or = 6 ng/ml and mild elevations of total CK activity were present in only 36.1 and 5.6%, respectively. Elevated cTnT was related to vascular complications in 44% of cases. Inapparent microembolization of platelets or plaque debris was considered responsible for most of the remaining micronecroses. During 6 month follow-up rates of clinical restenosis (44 vs 9%, p = 0.059) tended to be higher in patients with as compared to patients without cTnT release after DCA. Successful DCA is associated with postprocedural elevations of cTnT which relate to minor vascular complications and presumably microembolization of platelets or plaque debris. The superior diagnostic performance of cTnT compared to CK-MB mass may relate to more sensitive identification of microinfarction. Further studies are mandatory to confirm the association between elevation of cTnT and risk of restenosis and TVR.

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%).

Short‐ and long‐term outcome of balloon angioplasty for compromised side branches after intracoronary stent deployment

During coronary stent deployment there is a risk of compromising side branches, which can result in chest pain. Compromised side branches can be reopened by balloon angioplasty through the side of the stent. In a consecutive series of 10 patients with side-branch compromise and chest pain, balloon angioplasty through the side of the stent resolved the ischemia in all cases. The stented segment showed no deterioration following side-branch angioplasty. Six-month follow-up angiography showed a restenosis in the branch vessel of eight patients. The stented parent vessel restenosed in four patients. Therefore, side-branch balloon angioplasty after coronary stenting for ongoing ischemia is technically feasible and immediately effective. Restenosis of the branch occurs in most cases. Cathet. Cardiovasc. Intervent. 46:421–424, 1999. © 1999 Wiley-Liss, Inc.

Short- and long-term outcome of balloon angioplasty for compromised side branches after intracoronary stent deployment.

During coronary stent deployment there is a risk of compromising side branches, which can result in chest pain. Compromised side branches can be reopened by balloon angioplasty through the side of the stent. In a consecutive series of 10 patients with side-branch compromise and chest pain, balloon angioplasty through the side of the stent resolved the ischemia in all cases. The stented segment showed no deterioration following side-branch angioplasty. Six-month follow-up angiography showed a restenosis in the branch vessel of eight patients. The stented parent vessel restenosed in four patients. Therefore, side-branch balloon angioplasty after coronary stenting for ongoing ischemia is technically feasible and immediately effective. Restenosis of the branch occurs in most cases.

Side-branch occlusion with directional coronar atherectomy: Incidence and risk factors

Side-branch occlusion is a recognized complication of directional coronary atherectomy (DCA). To evaluate the incidence, risk factors, and clinical outcome of side-branch compromise, we analyzed our first 100 consecutive atherectomies of native coronary arteries. Seventy-eight patients had 122 side branches at risk, 21 (17%) of which demonstrated compromised flow after DCA. Origin of the side branch from the culprit atheroma and preexisting side-branch ostial stenosis were highly predictive of this complication in 20 of 55 ( p < 0.05) and 14 of 31 ( p < 0.05) lesions, respectively. There was one non-Q-wave myocardial infarction, no emergency surgeries, and no deaths. In conclusion, side-branch loss after DCA occurs with a frequency similar to balloon angioplasty and was well tolerated in our patient population. Side branches that originate directly from culprit lesions or that have significant ostial narrowing have a higher incidence of this complication.

Impact of directional atherectomy on adjacent branch vessels

Balloon angioplasty of bifurcation stenoses may lead to sidebranch compromise, particularly when the sidebranch is diseased and has its origin in the parent vessel occlusion. 1 Although the risk of sidebranch compromise may be reduced with the use of ≥2 protective coronary guide wires, 3,4 it is not eliminated. 2–4 Balloon angioplasty often results in plaque shifting from the parent vessel to the sidebranch, yielding a suboptimal angiographic result; in some cases, simultaneous (“kissing”) inflations of balloons positioned in the parent vessel and sidebranch may be needed. 3,4 Directional atherectomy, which partially or completely excises the obstructive plaque, has been used as an alternative method of therapy, avoiding the “snowplowing” effect of balloon angioplasty. The feasibility of directional atherectomy of bifurcation lesions was recently reported. 5 However, the incidence and risk factors for sidebranch compromise after directional atherectomy have been less clearly defined. To examine these issues, the clinical course of 60 patients undergoing directional coronary atherectomy of bifurcation lesions was reviewed.