"Subintimal external crush" technique for a "balloon uncrossable" chronic total occlusion.

Chronic total occlusion (CTO) revascularization is traditionally limited by the challenges related to lesion crossing. In a smaller number of cases, however, inability to advance the balloon catheter to the crossing site can account for recanalization failure ("balloon uncrossable" CTO). We describe a case of a "balloon uncrossable" CTO in which balloon crossing was achieved after subintimal dilation and "external crushing" of the CTO lesion resulting in significant modification of the CTO atheromatous plaque.

Long-term outcomes with first- vs. second-generation drug-eluting stents in saphenous vein graft lesions.

BACKGROUND: As compared with bare metal stents, first-generation drug-eluting stents (DES) improved post-procedural outcomes in aortocoronary saphenous vein graft (SVG) lesions, but there is limited information on outcomes after use of second-generation DES in SVGs. METHODS: We compared the outcomes of patients who received first- (n = 81) with those who received second-generation (n = 166) DES in SVG lesions at our institution between 2006 and 2013. Major adverse cardiac events (MACE) were defined as the composite of all-cause death, myocardial infarction, and target vessel revascularization. RESULTS: Mean age was 66.0 ± 8.1 years and 97.6% of the patients were men. Mean SVG age was 11.1 ± 0.4 years. First-generation DES were sirolimus-eluting (n = 17) and paclitaxel-eluting (n = 64) stents. Second-generation DES were everolimus-eluting (n = 115) and zotarolimus-eluting (n = 51) stents. Median follow-up was 41 months. At 2-years post-procedure, patients with first- and second-generation DES had similar rates of death (20.91% vs. 20.27%, P = 0.916), target lesion revascularization (16.39% vs. 20.00%, P = 0.572), target vessel revascularization (20.97% vs. 23.16%, P = 0.747), myocardial infarction (26.15% vs. 23.00%, P = 0.644), and MACE (43.5% vs. 40.87%, P = 0.707), respectively. CONCLUSIONS: Outcomes with first- and second-generation DES in SVGs are similar. Novel stent designs are needed to further improve the clinical outcomes in this challenging patient and lesion subgroup. © 2015 Wiley Periodicals, Inc.

Effect of Extended-Release Niacin on Saphenous Vein Graft Atherosclerosis: Insights from the Atherosclerosis Lesion Progression Intervention Using Niacin Extended Release in Saphenous Vein Grafts (ALPINE-SVG) Pilot Trial.

BACKGROUND: Intermediate saphenous vein graft (SVG) lesions have high rates of progression. The purpose of this study was to examine the impact of extended-release niacin (ER-niacin) vs placebo on intermediate SVG lesions. METHODS: Patients with intermediate (30%-60% diameter stenosis) SVG lesions were randomized to ER-niacin vs placebo for 12 months. Quantitative coronary angiography (QCA), intravascular ultrasonography (IVUS), and optical coherence tomography (OCT) were performed at baseline and at 12 months. The primary endpoint was change in percent atheroma volume (ΔPAV). Enrollment was planned for 138 patients for 90% power to detect ≥2.5% difference in the primary endpoint of ΔPAV, but stopped early after publication of two negative outcome trials of ER-niacin, with enrolled patients completing the 12-month trial protocol. RESULTS: Thirty-eight patients were randomized to niacin (n = 19) or placebo (n = 19), yielding power of 47% to detect the primary planned treatment effect of 2.5 ± 4.0% difference in ΔPAV. Between baseline and 12-month follow-up, no significant difference was found between study groups in ΔPAV (-1.31 ± 6.05% vs 1.05 ± 17.8%; P=.60). By OCT, the ER-niacin vs placebo group had less plaque rupture within the intermediate SVG lesion (0.0% vs 36.0%; P=.01). CONCLUSION: Administration of ER-niacin did not significantly impact intermediate SVG disease, with the notable limitation of compromised statistical power due to early termination of enrollment.

The Double-Blind Stick-and-Swap Technique for True Lumen Reentry After Subintimal Crossing of Coronary Chronic Total Occlusions.

Subintimal dissection and reentry techniques are widely used in chronic total occlusion (CTO) interventions; however, inability to reenter into the distal true lumen is a common cause of failure. In some patients, subintimal hematoma may develop, compressing the lumen and hindering reentry. We describe 3 CTO cases in which the distal vessel could not be visualized after subintimal crossing, in spite of attempts to decompress the subintimal hematoma. Bidirectional "blind" puncture was performed with the Stingray wire through both ports of the Stingray balloon, followed by exchange of the Stingray wire for a Pilot 200 guidewire (the "double-blind stick-and-swap" technique) achieving distal true lumen reentry.

Comparison of Iodixanol and Ioxaglate for Coronary Optical Coherence Tomography Imaging.

BACKGROUND: The impact of contrast type on coronary imaging using optical coherence tomography (OCT) has received limited study. We compared OCT imaging obtained using the non-ionic, iso-osmolar iodixanol with the ionic, low-osmolar ioxaglate. METHODS: Twenty-two vessels in 20 patients were imaged twice using manual injection of iodixanol and ioxaglate in random order. OCT images were analyzed at 1 mm intervals to determine lumen area, artifact diameter and area, as well as stent strut coverage and malapposition in OCT pullbacks that included stents. RESULTS: There were no complications related to OCT imaging or to contrast administration. A total of 2184 cross-sections (1092 with iodixanol and 1092 with ioxaglate) were analyzed. Compared with iodixanol, imaging using ioxaglate provided similar mean lumen area (6.21 ± 2.83 mm2 vs 6.27 ± 2.83 mm2; Spearman's rho, 0.982), mean minimum lumen diameter (2.47 ± 0.59 mm vs 2.50 ± 0.58 mm; Spearman's rho, 0.939), and mean maximum lumen diameter (2.99 ± 0.71 mm vs 3.01 ± 0.70 mm; Spearman's rho, 0.964), but lower mean artifact area per cross-section (0.099 ± 0.325 mm2 vs 0.068 ± 0.329 mm2; P<.001). Analyses of 3303 stent struts in 388 cross-sections (194 with iodixanol and 194 with ioxaglate) demonstrated similar strut malapposition rates (11.82% vs 13.90%; P=.10) and strut coverage (41.92% vs 40.33%; P=.35). CONCLUSIONS: Compared with iodixanol, OCT imaging using ioxaglate provided similar lumen and diameter measurements and stent strut characterization, but smaller area of artifact.

Prevalence and treatment of "balloon-uncrossable" coronary chronic total occlusions.

BACKGROUND: The frequency and outcomes of "balloon-uncrossable" coronary chronic total occlusions (CTOs) have received limited study. METHODS: We retrospectively examined 373 consecutive CTO percutaneous coronary interventions (PCIs) performed at our institution between 2005 and 2013 to determine the frequency and treatment of balloon-uncrossable CTOs. RESULTS: Mean age was 63.7 ± 8.3 years and 98.9% of the patients were men. Twenty-four patients (6.4%, 95% confidence intervals 4.2% to 9.4%) were found to have a balloon-uncrossable CTO. Compared to the other CTO PCI patients, those with balloon-uncrossable CTOs had similar clinical and angiographic characteristics. Successful crossing of the balloon-uncrossable CTO was achieved in 22 of 24 patients (91.7%) using a variety of techniques, such as successive balloon inflations (43.5%), microcatheter advancement (21.7%), laser (8.7%), techniques that increase guide catheter support (13.0%), and subintimal lesion crossing (13.0%). Patients with balloon-uncrossable CTOs had longer procedure time (184.5 ± 77.9 vs 134.0 ± 69.0 min, P<.01), fluoroscopy time (55.2 ± 24.9 vs 37.9 ± 20.8 min, P<.01), and received high contrast volume (404.4 ± 137.9 vs 351.7 ± 138.5 mL, P=.08), but had similar incidence of major complications (8.3% vs 3.2%, P=.25) as compared with patients who did not have balloon-uncrossable CTOs. CONCLUSION: Balloon-uncrossable CTOs are encountered in 6.4% of contemporary CTO PCIs and can be successfully treated in most patients using a variety of techniques.

Transradial approach for coronary chronic total occlusion interventions: Insights from a contemporary multicenter registry.

OBJECTIVES: To examine the impact of transradial access on the procedural outcomes of chronic total occlusion (CTO) percutaneous coronary interventions (PCI). BACKGROUND: The efficacy and safety of transradial access in CTO PCI has received limited study. METHODS: We compared the technique and outcomes of transradial vs. transfemoral access among 650 CTO PCI cases performed between January 2012 and March 2014 at 6 US centers. RESULTS: Most patients were men (87%) with high frequency of diabetes mellitus (42%) and prior coronary artery bypass graft surgery (36%). The CTO target vessel was the right coronary (59%), left anterior descending (20%), or circumflex (17%) artery. TR access was used in 110 (17%) of the 650 cases, as follows: bilateral radial access (63%); bilateral radial access plus unilateral or bilateral femoral access (7%); unilateral radial access plus unilateral or bilateral femoral access (26%); and unilateral radial access (4%). Six and eight French guide catheters were used through the radial and femoral artery, respectively. Compared to transfemoral, transradial cases had similar technical (92.6% vs. 93.0%, P = 0.87) and procedural (91.1% vs. 90.0%, P = 0.95) success and major complication rates (1.7% vs 1.8%, P = 0.99). However, transradial access was associated with higher mean procedure (142 ± 83 vs. 120 ± 60 min, P = 0.008) and fluoroscopy (58 ± 40 vs. 49 ± 31 min, P <0.026) time, and number of crossing approach changes (0.7 ± 1.0 vs. 0.5 ± 0.7, P = 0.008). CONCLUSION: Transradial CTO PCI can be performed with similar success and complication rates with transfemoral CTO PCI, but is associated with longer procedural and fluoroscopy times. © 2015 Wiley Periodicals, Inc.

Procedural failure of chronic total occlusion percutaneous coronary intervention: Insights from a multicenter US registry.

BACKGROUND: The hybrid approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) has significantly increased procedural success rates, yet some cases still fail. We sought to evaluate the causes of failure in a contemporary CTO PCI registry. METHODS: We examined 380 consecutive patients who underwent CTO-PCI at 4 high volume CTO PCI centers in the United States using the "hybrid" approach. Clinical, angiographic, complication, and efficiency outcomes were compared between successful and failed cases. Failed cases were individually reviewed by an independent reviewer to determine the cause of failure. RESULTS: Procedural success was 91.3%. Compared with patients in whom CTO PCI was successful, those in whom CTO PCI failed had similar baseline clinical characteristics, but were more likely to have longer occlusion length, more tortuosity, more proximal cap ambiguity and blunt stump, and higher mean J-CTO scores (2.8 ± 1.1 vs. 3.5 ± 1.0, P < 0.001), and less likely to have collaterals suitable for the retrograde approach (66% vs. 45%, P = 0.021). Failure was due to a complication in 10 cases (30%). In the remaining 23 cases (70%) failure was due to inability to wire the lesion (n = 21, 4 of which were CTOs due to in-stent restenosis), or poor antegrade flow after PCI (n = 5). CONCLUSIONS: Compared with successful cases, failed CTO-PCI cases are more likely to have higher J-CTO scores, longer occlusion length, ambiguous proximal cap and no appropriate collaterals for retrograde crossing. Development of novel CTO crossing techniques is needed to further increase CTO PCI success rates.

Outcomes of preoperative bridging therapy for patients undergoing surgery after coronary stent implantation: a weighted meta-analysis of 280 patients from eight studies.

BACKGROUND: Preoperative bridging with a glycoprotein IIb/IIIa inhibitor is often performed in patients with prior coronary stents undergoing surgery who require antiplatelet therapy discontinuation, but its safety and efficacy have received limited study. We performed a weighted meta-analysis of the outcomes in patients with coronary stents undergoing bridging with glycoprotein IIb/IIIa inhibitors prior to surgery. METHODS: We conducted a weighted meta-analysis of preoperative bridging studies published between 2002 and 2013 in patients with coronary stents undergoing surgery. Data on in-hospital mortality, stent thrombosis, bleeding, hemoglobin decrease, blood transfusion, time to hospital discharge and myocardial infarction were collected. RESULTS: A total of eight studies with 280 patients were included. Pooled estimates of outcomes were as follows: in-hospital mortality 3.5% (95% confidence interval [CI] 1.7-5.9%); stent thrombosis 1.3% (95% CI 0.3-3.0%); major bleeding 7.4% (95% CI 2.8-14.1%); any bleeding 20.6% (95% CI 4.8-43.2%); mean decrease in hemoglobin 2.8 g/dL (95% CI 2.5-3.0 g/dL); mean blood loss 271 mL (95% CI 211-311 mL); blood transfusion 13.9% (95% CI 1.0-38.2%); time to hospital discharge 5.9 days (95% CI 4.4-7.3 days); and myocardial infarction 1.6% (95% CI 0.3-3.6%). CONCLUSIONS: Preoperative bridging with a glycoprotein IIb/IIIa inhibitor in patients undergoing surgery after coronary stenting does not abolish the risk of perioperative stent thrombosis and may carry increased risk for bleeding. © 2014 Wiley Periodicals, Inc.

Percutaneous intervention of circumflex chronic total occlusions is associated with worse procedural outcomes: insights from a Multicentre US Registry.

BACKGROUND: We sought to determine whether outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) vary according to CTO target vessel: left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA). METHODS: We evaluated the clinical and angiographic characteristics and procedural outcomes of 636 patients who underwent CTO PCI at 6 high-volume centres in the United States between January 2012 and March 2014. RESULTS: The CTO target vessel was the RCA in 387 cases (61%), LAD in 132 (21%), and LCX in 117 (18%). LCX lesions were more tortuous and RCA lesions had greater occlusion length and Japanese Chronic Total Occlusion (J-CTO) score, but were less likely to have a side branch at the proximal cap and had more developed collateral circulation. The rate of procedural success was lower in LCX CTOs (84.6%), followed by RCA (91.7%), and LAD (94.7%) CTOs (P = 0.016). Major complications tended to occur more frequently in LCX PCI (4.3% vs 1.0% for RCA vs 2.3% for LAD; P = 0.07). LCX and RCA CTO PCI required longer fluoroscopy times (45 [interquartile range (IQR), 30-74] minutes vs 45 [IQR, 21-69] minutes for RCA vs 34 [IQR, 20-60] minutes for LAD; P = 0.018) and LCX CTOs required more contrast administration (280 [IQR, 210-370] mL vs 250 [IQR, 184-350] mL for RCA and 280 [IQR, 200-400] mL for LAD). CONCLUSIONS: In a contemporary, multicentre CTO PCI registry, LCX was the least common target vessel. Compared with LAD and RCA, PCI of LCX CTOs was associated with a lower rate of procedural success, less efficiency, and a nonsignificant trend for higher rates of complications.

The efficacy and safety of the "hybrid" approach to coronary chronic total occlusions: insights from a contemporary multicenter US registry and comparison with prior studies.

BACKGROUND: Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is challenging and has been associated with low success rates. However, recent advancements in equipment and the flexibility to switch between multiple technical approaches during the same procedure ("hybrid" percutaneous algorithm) have dramatically increased the success of CTO-PCI. We sought to compare the contemporary procedural outcomes of hybrid CTO-PCI with previously published CTO-PCI studies. METHODS: The procedural outcomes of 497 consecutive CTO-PCIs performed between January 2012 and August 2013 at five high-volume centers in the United States were compared with the pooled success and complication rates reported in 39 prior CTO-PCI series that included ≥100 patients and were published after 2000. RESULTS: The baseline clinical and angiographic characteristics of the study patients were comparable to those of previous studies. Technical and procedural success was achieved in 455 cases (91.5%) and 451 cases (90.7%), respectively, and were significantly higher than the pooled technical and procedural success rates from prior studies (76.5%, P<.001 and 75.2%, P<.001, respectively). Major procedural complications occurred in 9/497 patients (1.8%) overall and included death (2 patients), acute myocardial infarction (5 patients), repeat target vessel PCI (1 patient), and tamponade requiring pericardiocentesis (2 patients). The incidence of major complications was similar to that of prior studies (pooled rate 2.0%; P=.72). CONCLUSION: Use of the hybrid approach to CTO-PCI is associated with higher success and similar complication rates compared to prior studies, supporting its expanded use for treating these challenging lesions.

Thrombin injection for sealing epicardial collateral perforation during chronic total occlusion percutaneous coronary interventions.

Epicardial collateral perforation is a serious complication of retrograde chronic total occlusion percutaneous coronary intervention. We describe two cases of epicardial collateral perforation that were successfully sealed with local thrombin injection.

Application of the "hybrid approach" to chronic total occlusions in patients with previous coronary artery bypass graft surgery (from a Contemporary Multicenter US registry).

Percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs) has been traditionally associated with lower success rates in patients with previous coronary artery bypass graft surgery (CABG). We sought to examine the success and complication rates of CTO PCI using the "hybrid" crossing algorithm among patients with a history of previous CABG. The procedural outcomes of 496 consecutive CTO PCIs performed at 5 high-volume PCI centers in the United States from January 2012 to August 2013 were assessed. The outcomes of patients with previous CABG were compared with those of patients without previous CABG. Compared with patients without previous CABG (n = 320), patients with previous CABG (n = 176, 35%) were older, had more coronary artery disease risk factors, and had less favorable baseline angiographic CTO characteristics. Technical and procedural success was slightly lower among patients with previous CABG (88.1% vs 93.4%, p = 0.044 and 87.5 vs 92.5%, p = 0.07, respectively). Patients with previous CABG more commonly underwent CTO PCI using the retrograde approach (39% vs 24%, respectively, p <0.001) and received higher air kerma radiation exposure (4.8 [interquartile range 3.0 to 6.4] vs 3.1 [1.9 to 5.3] Gray, p <0.001) and fluoroscopy time (59 [38 to 77] vs 34 [21 to 55] minutes, p <0.001). Major procedural complications were similar in the 2 groups: 2 of 176 (1.1%) patients with previous CABG versus 7 of 320 (2.1%) patients without previous CABG (p = 0.40). In conclusion, with application of the "hybrid" approach to CTO PCI, success was slightly lower, and complication rates were similar between patients with and without previous CABG.

The efficacy of "hybrid" percutaneous coronary intervention in chronic total occlusions caused by in-stent restenosis: insights from a US multicenter registry.

OBJECTIVES: To examine the success and complication rates in percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) caused by in-stent restenosis (ISR). BACKGROUND: PCI for in-stent total occlusive disease has traditionally been associated with low success rates. We sought to examine angiographic and procedural outcomes of patients who underwent CTO PCI due to ISR using the novel "hybrid" algorithm, and compare them with patients with de novo CTOs. METHODS: We examined 521 consecutive patients who underwent CTO PCI at five high-volume PCI centers in the United States using the "hybrid" approach. Clinical, angiographic, and procedural outcomes were compared between CTOs due to ISR and de novo CTOs. RESULTS: The target CTO was due to ISR in 57 of 521 patients (10.9%). Compared to patients with de novo CTOs, those with CTO due to ISR had higher frequency of diabetes (56.1% vs. 39.6%, P = 0.02) and less calcification (5.3% vs. 16.2%, P <0.001), but longer occlusion length [38 (29-55) vs. 30 (20-51), P = 0.04]. Technical success in the ISR and de novo group was 89.4% and 92.5% (P = 0.43), respectively; procedural success was 86.0% and 90.3% (P = 0.31), respectively; and the incidence of major adverse cardiac events was 3.5% and 2.2% (P = 0.63), respectively. CONCLUSIONS: Use of the "hybrid" approach to CTO PCI was associated with similarly high procedural success and similarly low major complication rates in patients with de novo and ISR CTOs.

Torsade de Pointes and Persistent QTc Prolongation after Intravenous Amiodarone.

We report a case of torsade de pointes after intravenous amiodarone and concurrent hypokalemia. Despite treatment cessation and correction of electrolyte abnormalities, excessive QTc prolongation was noted, which persisted for 14 days. This prolonged course for QTc normalization may be attributed to the high rate of amiodarone loading and concurrent electrolyte disturbances coupled with possible underlying individual variability in pharmacokinetics.

Effect of a synthetic peptide corresponding to residues 313 to 320 of the alphaIIb subunit of the human platelet integrin alphaIIbbeta3 on carotid artery thrombosis in rabbits.

The platelet integrin receptor alpha(IIb)beta(3) plays a critical role in thrombosis. We have shown previously that the octapeptide YMESRADR, corresponding to sequences 313 to 320 of the human alpha(IIb) subunit, inhibits human platelet activation and fibrinogen binding to alpha(IIb)beta(3), possibly interacting with the ligand. We investigated the effect of YMESRADR on electrically induced carotid artery thrombosis in New Zealand white rabbits. Peptide was administered via the femoral vein, starting 60 min before and continuing for 90 min after the electrical stimulation. Carotid blood flow was monitored for 90 min after the electrical stimulation. The peptide effects on platelet aggregation, in vitro and ex vivo, and on various coagulation, bleeding, and hemostatic parameters were evaluated. YMESRADR significantly inhibited rabbit platelet aggregation in vitro in a dose-dependent manner. It is important that peptide administration in vivo, at doses ranging from 3 to 15 mg/kg, prolonged the duration of the patency of the carotid artery, and no artery occlusion was observed until the end of the study (90 min after electrical stimulation). Furthermore, YMESRADR administration reduced platelet aggregation ex vivo and thrombus weight; however, these reductions reached statistical significance, compared with the control group, at the peptide doses of 12 and 15 mg/kg. YMESRADR did not affect any coagulation parameter studied and the hemostatic response observed in control animals. Thus, YMESRADR represents a novel antiplatelet agent that can inhibit thrombus formation effectively and carotid artery occlusion without causing hemorrhagic complications in a rabbit model of arterial thrombosis.

Automated diagnosis of coronary artery disease based on data mining and fuzzy modeling.

A fuzzy rule-based decision support system (DSS) is presented for the diagnosis of coronary artery disease (CAD). The system is automatically generated from an initial annotated dataset, using a four stage methodology: 1) induction of a decision tree from the data; 2) extraction of a set of rules from the decision tree, in disjunctive normal form and formulation of a crisp model; 3) transformation of the crisp set of rules into a fuzzy model; and 4) optimization of the parameters of the fuzzy model. The dataset used for the DSS generation and evaluation consists of 199 subjects, each one characterized by 19 features, including demographic and history data, as well as laboratory examinations. Tenfold cross validation is employed, and the average sensitivity and specificity obtained is 62% and 54%, respectively, using the set of rules extracted from the decision tree (first and second stages), while the average sensitivity and specificity increase to 80% and 65%, respectively, when the fuzzification and optimization stages are used. The system offers several advantages since it is automatically generated, it provides CAD diagnosis based on easily and noninvasively acquired features, and is able to provide interpretation for the decisions made.