Craig A. Thompson

Successful Recanalization of Chronic Total Occlusions Is Associated With Improved Long-Term Survival

OBJECTIVES This study investigated the impact of procedural success on mortality following chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in a large cohort of patients in the drug-eluting stent era. BACKGROUND Despite advances in expertise and technologies, many patients with CTO are not offered PCI. METHODS A total of 6,996 patients underwent elective PCI for stable angina at a single center (2003 to 2010), 836 (11.9%) for CTO. All-cause mortality was obtained to 5 years (median: 3.8 years; interquartile range: 2.0 to 5.4 years) and stratified according to successful chronic total occlusion (sCTO) or unsuccessful chronic total occlusion (uCTO) recanalization. Major adverse cardiac events (MACE) included myocardial infarction (MI), urgent revascularization, stroke, or death. RESULTS A total of 582 (69.6%) procedures were successful. Stents were implanted in 97.0% of successful procedures (mean: 2.3 ± 0.1 stents per patient, 73% drug-eluting). Prior revascularization was more frequent among uCTO patients: coronary artery bypass grafting (CABG) (16.5% vs. 7.4%; p < 0.0001), PCI (36.0% vs. 21.2%; p < 0.0001). Baseline characteristics were otherwise similar. Intraprocedural complications, including coronary dissection, were more frequent in unsuccessful cases (20.5% vs. 4.9%; p < 0.0001), but did not affect in-hospital MACE (3% vs. 2.1%; p = NS). All-cause mortality was 17.2% for uCTO and 4.5% for sCTO at 5 years (p < 0.0001). The need for CABG was reduced following sCTO (3.1% vs. 22.1%; p < 0.0001). Multivariate analysis demonstrated that procedural success was independently predictive of mortality (hazard ratio [HR]: 0.32 [95% confidence interval (CI): 0.18 to 0.58]), which persisted when incorporating a propensity score (HR: 0.28 [95% CI: 0.15 to 0.52]). CONCLUSIONS Successful CTO PCI is associated with improved survival out to 5 years. Adoption of techniques and technologies to improve procedural success may have an impact on prognosis.

Percutaneous transvenous cellular cardiomyoplasty

Objectives The study evaluated a nonsurgical means of intramyocardial cell introduction using the coronary venous system for direct myocardial access and cell delivery. Background Direct myocardial cell repopulation has been proposed as a potential method to treat heart failure. Methods We harvested bone marrow from Yorkshire swine (n = 6; 50 to 60 kg), selected culture-flask adherent cells, labeled them with the gene for green fluorescence protein, expanded them in culture, and resuspended them in a collagen hydrogel. Working through the coronary sinus, a specialized catheter system was easily delivered to the anterior interventricular coronary vein. The composite catheter system (TransAccess) incorporates a phased-array ultrasound tip for guidance and a sheathed, extendable nitinol needle for transvascular myocardial access. A microinfusion (IntraLume) catheter was advanced through the needle, deep into remote myocardium, and the autologous cell–hydrogel suspension was injected into normal heart. Animals were sacrificed at days 0 (n = 2), 14 (n = 1, + 1 control/collagen biogel only), and 28 (n = 2), and the hearts were excised and examined. Results We gained widespread intramyocardial access to the anterior, lateral, septal, apical, and inferior walls from the anterior interventicular coronary vein. No death, cardiac tamponade, ventricular arrhythmia, or other procedural complications occurred. Gross inspection demonstrated no evidence of myocardial perforation, and biogel/black tissue dye was well localized to sites corresponding to fluoroscopic landmarks for delivery. Histologic analysis demonstrated needle and microcatheter tracts and accurate cell–biogel delivery. Conclusions Percutaneous intramyocardial access is safe and feasible by a transvenous approach through the coronary venous system. The swine offers an opportunity to refine approaches used for cellular cardiomyoplasty.

Sodium Bicarbonate Plus N-Acetylcysteine Prophylaxis: A Meta-Analysis

OBJECTIVES We sought to conduct a meta-analysis to compare N-acetylcysteine (NAC) in combination with sodium bicarbonate (NaHCO(3)) for the prevention of contrast-induced acute kidney injury (AKI). BACKGROUND Contrast-induced AKI is a serious consequence of cardiac catheterizations and percutaneous coronary interventions (PCI). Despite recent supporting evidence for combination therapy, not enough has been done to prevent the occurrence of contrast-induced AKI prophylactically. METHODS Published randomized controlled trial data were collected from OVID/PubMed, Web of Science, and conference abstracts. The outcome of interest was contrast-induced AKI, defined as a >or=25% or >or=0.5 mg/dl increase in serum creatinine from baseline. Secondary outcome was renal failure requiring dialysis. RESULTS Ten randomized controlled trials met our criteria. Combination treatment of NAC with intravenous NaHCO(3) reduced contrast-induced AKI by 35% (relative risk: 0.65; 95% confidence interval: 0.40 to 1.05). However, the combination of N-acetylcysteine plus NaHCO(3) did not significantly reduce renal failure requiring dialysis (relative risk: 0.47; 95% confidence interval: 0.16 to 1.41). CONCLUSIONS Combination prophylaxis with NAC and NaHCO(3) substantially reduced the occurrence of contrast-induced AKI overall but not dialysis-dependent renal failure. Combination prophylaxis should be incorporated for all high-risk patients (emergent cases or patients with chronic kidney disease) and should be strongly considered for all interventional radio-contrast procedures.

The retrograde technique for recanalization of chronic total occlusions: a step-by-step approach.

Chronic total occlusion recanalization still represents the final frontier in percutaneous coronary intervention. Retrograde chronic total occlusion recanalization has recently become an essential complement to the classical antegrade approach. In experienced hands, the retrograde technique currently has a high success rate with a low complication profile, despite frequent utilization in the most anatomically and clinically complex patients. Since its initial description, important changes have occurred that make the technique faster and more successful. We propose a step-by-step approach of the technique as practiced at experienced centers in North America. Because the technique can vary substantially, we describe the different alternatives to each step and offer what we perceived to be the most efficient techniques.

Use of a novel crossing and re-entry system in coronary chronic total occlusions that have failed standard crossing techniques: Results of the FAST-CTOs (facilitated antegrade steering technique in chronic total occlusions) trial

OBJECTIVES This study sought to examine the efficacy and safety of 3 novel devices to recanalize coronary chronic total occlusions (CTOs). BACKGROUND Successful percutaneous coronary intervention (PCI) of CTOs improves clinical outcome in appropriately selected patients. CTO PCI success, however, remains suboptimal. METHODS A new crossing catheter and re-entry system was evaluated in a prospective, multicenter, single-arm trial of CTO lesions refractory to standard PCI techniques. The primary efficacy endpoint was the frequency of true lumen guidewire placement distal to the CTO (technical success). RESULTS Enrollment included 147 patients with 150 CTOs. The mean lesion length was 41 ± 17 mm. A crossing catheter crossed 56 lesions into the distal true lumen, and a re-entry catheter facilitated tapered-wire cannulation of the distal lumen in 59 CTOs initially crossed subintimally (77% technical success). Success in the first 75 CTOs was 67%, rising to 87% in the last 75 CTOs. Mean fluoroscopy and procedure times were 45 ± 16 min and 90 ± 12 min, respectively, each significantly shorter than in historical controls (p < 0.0001 for both). Coronary perforation occurred in 14 cases (9.3%), requiring treatment in 3 cases (prolonged balloon inflation, with additional coil embolization in 1 case). No tamponade or hemodynamic instability occurred. Six patients had periprocedural non-ST-segment elevation myocardial infarction. No emergency surgery, ST-segment elevation myocardial infarction, or cardiac reintervention occurred. Two deaths occurred within 30 days, neither as a direct result of the procedure. The 30-day major adverse cardiac event rate was 4.8%. CONCLUSIONS In CTOs failing standard techniques, use of a new crossing and re-entry system results in a high success rate without increasing complications.

The retrograde approach to coronary artery chronic total occlusions: a practical approach.

The retrograde approach has revolutionized the treatment of chronic total occlusions. Several retrograde techniques have recently been described. In this article, we present a practical review with step‐by‐step instructions on the indications for retrograde interventions, equipment and retrograde channel selection, and techniques for retrograde crossing and treatment of chronic total occlusions.

Dynamic rotational seeding and cell culture system for vascular tube formation.

Optimization of cell seeding and culturing is an important step for the successful tissue engineering of vascular conduits. We evaluated the effectiveness of using a hybridization oven for rotational seeding and culturing of ovine vascular myofibroblasts onto biodegradable polymer scaffolds suitable for replacement of small- and large-diameter blood vessels. Large tubes (12 mm internal diameter and 60 mm length, n = 4) and small tubes (5 mm internal diameter and 20 mm length, n = 4) were made from a combination of polyglycolic acid/poly-4-hydroxybutyrate and coated with collagen solution. Tubes were then placed in culture vessels containing a vascular myofibroblast suspension (10(6) cells/cm(2)) and rotated at 5 rpm in a hybridization oven at 37 degrees C. Light and scanning electron microscopy analyses were performed after 5, 7, and 10 days. Myofibroblasts had formed confluent layers over the outer and inner surfaces of both large and small tubular scaffolds by day 5. Cells had aligned in the direction of flow by day 7. Multiple spindle-shaped cells were observed infiltrating the polymer mesh. Cell density increased between day 5 and day 10. All conduits maintained their tubular shape throughout the experiment. We conclude that dynamic rotational seeding and culturing in a hybridization oven is an easy, effective, and reliable method to deliver and culture vascular myofibroblasts onto tubular polymer scaffolds.

Transient and persistent renal dysfunction are predictors of survival after percutaneous coronary intervention: Insights from the Dartmouth Dynamic Registry†

Objectives: We sought to determine if transient and persistent elevations in creatinine following percutaneous coronary intervention (PCI) resulted in poor survival. Background: Limited survival data exist that defines the natural survival history of transient and persistent renal dysfunction following interventional PCI cases. Methods: Data were collected prospectively on 7,856 consecutive patients undergoing PCI from January 1, 2000 to July 31, 2006. Ninety‐three patients were excluded due to pre‐PCI dialysis. Patients were stratified into three categories of renal dysfunction: no renal dysfunction from baseline (<0.5 mg/dL increase in creatinine within 48 hr of the procedure), transient renal dysfunction (≥0.5 mg/dL increase in creatinine within 48 hr with return to normal within 2 weeks), and persistent renal dysfunction (≥0.5 mg/dL increase in creatinine without returning to normal within 2 weeks of the procedure). Mortality was determined by comparing with the Social Security Death Master File. Results: Median survival was 3.2 years (mean 3.4). Renal dysfunction occurred in 250 patients (0.5 mg/dL increase in creatinine). Survival was significantly different between patients at 1, 3.2, and 7.5 years (P‐value < 0.001): no renal dysfunction (95%, 88%, 75%), with transient (61%, 42%, 0%), and with persistent (58%, 44%, 36%) renal dysfunction. Patients with transient or persistent renal dysfunction had a twofold–threefold increased risk of 7.5‐year mortality compared with patients with no renal dysfunction. Conclusions: Both transient and persistent postprocedural renal dysfunction are prognostically significant for mortality during extended follow‐up. Renal dysfunction should be closely monitored before and after PCI.

Application and outcomes of a hybrid approach to chronic total occlusion percutaneous coronary intervention in a contemporary multicenter US registry

BACKGROUND A hybrid approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) prioritizing and combining all available crossing techniques was developed to optimize procedural efficacy, efficiency, and safety, but there is limited published data on its outcomes. METHODS We examined the procedural techniques and outcomes of 1036 consecutive CTO PCIs performed using a hybrid approach between 2012 and 2015 at 11 US centers. RESULTS Mean age was 65 ± 10 years and 86% of the patients were men, with a high prevalence of diabetes mellitus (43%) and prior coronary artery bypass graft surgery (34%). Most target CTOs were located in the right coronary artery (59%), followed by the left anterior descending artery (23%) and the circumflex (19%). Dual injection was used in 71%. Technical success was achieved in 91% and a major procedural complication occurred in 1.7% of cases. The final successful crossing technique was antegrade wire escalation in 46%, antegrade dissection/re-entry in 26%, and retrograde in 28%. The initial crossing strategy was successful in 58% of the lesions, whereas 39% required an additional approach. Overall, antegrade wire escalation was used in 71%, antegrade dissection/re-entry in 36%, and the retrograde approach in 42% of procedures. Median contrast volume, fluoroscopy time, and air kerma radiation dose were 260 (200-360) ml, 44 (27-72) min, and 3.4 (2.0-5.4) Gray, respectively. CONCLUSION Application of a hybrid approach to CTO crossing resulted in high success and low complication rates across a varied group of operators and hospital practice structures, supporting its expanding use in CTO PCI.

Gender-based differences of percutaneous coronary intervention in the drug-eluting stent era.

Objectives: The purpose of this study is to provide insights into percutaneous coronary intervention (PCI) performed in women in the United States by evaluating gender‐based PCI‐practice patterns and outcomes. Background: Limited “real world” contemporary data exist on how the introduction of DES has impacted PCI in women. Methods and Results: Patients (359 women, 807 men) with de novo coronary artery disease having PCI (1,166) were evaluated during the first year, since the introduction of DES in the United States market (May 1, 2003 to April 30, 2004). Women were more likely to be older, hypertensive, obese, diabetic, and have heart failure. Men were more likely to be smokers and have more vessels with obstructive coronary artery disease. PCI procedural success rates, number of vessels attempted, percentage DES utilization, and in‐hospital major adverse cardiac events (MACE; death, new myocardial infarction, urgent revascularization) were similar for both genders. However, women had significantly higher unadjusted mortality (3.9% versus 1.6%, P = 0.01), cumulative vascular complications (12.0% versus 4.2%, P < 0.0001), and renal failure (2.5% versus 0.7%, P = 0.01). After adjustment for confounding variables, mortality was similar between genders, but a significant association with vascular complications and trend toward higher rates of renal failure persisted in women. Conclusions: In this study of the modern era of PCI with DES utilization, in‐hospital MACE is similar between men and women. However, the differences in baseline comorbidities and the proclivity for vascular and renal complications highlight the need for further investigation and improvements to optimize outcomes of PCI in women.