Faculty Bibliography

OBJECTIVES/OBJECTIVE: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.

OBJECTIVE:The purpose of this investigation was to characterize clinical variables and angiographic distribution of coronary atherosclerosis to classify patients with de novo left main (LM) disease in a real-world population presenting for coronary angiography. BACKGROUND:Limited quantitative and angiographic published data exist that provide detailed quantitative information to classify potential target population for elective LM percutaneous coronary intervention (PCI) and guide development of dedicated LM PCI platforms. METHODS:Medical history and clinical presentation were prospectively collected on 177 consecutive patients with LM stenosis > or =50% by coronary angiography. Blinded quantitative coronary angiography (QCA) was performed on all LM stenoses to classify LM-A (ostial), LM-B (nonostial, non-bifurcation), and LM-C (bifurcation involvement). QCA was performed on the left anterior descending (LAD), left circumflex (LCx), and right coronary arteries (RCA) and branches (> or =2.5 mm) to identify lesions with > or =60% stenosis or occlusion. RESULTS:No differences in baseline clinical history or presentation discriminated the distribution patterns of LM stenosis. QCA revealed 66% of LM stenoses were LM-C. Mean LM reference vessel diameter was 4.65 mm and average lesion length was 11.12 mm. Around 88.7% of patients had at least one lesion > or =60% in a major epicardial artery and 32.2% of patients had RCA chronic total occlusion. Right-to-left coronary collateralization was only identified in patients with obstructive stenosis in the LAD or LCx in addition to the LM stenosis. CONCLUSION/CONCLUSIONS:Dedicated LM stent platforms may need to be developed to accommodate larger vessel size and bifurcation distributions. A majority of patients with LM stenosis will require adjunctive epicardial vessel PCI to achieve complete anatomic revascularization.

OBJECTIVES/OBJECTIVE:Our purpose was to determine if "Japanese style" technical strategies can be successfully applied in the U.S. practice environment and to better understand the learning curve for chronic total occlusion (CTO) percutaneous coronary intervention (PCI). BACKGROUND:Procedural technical success remains the major limiting factor for CTO PCI, and has been unchanged over time. METHODS:Demographic, procedural, and outcome data were collected on 636 consecutive patients between January 2005 and March 2008 having CTO PCI (514 antegrade, 122 retrograde attempts) at 2 U.S. medical centers. Operators were divided into 2 groups: higher CTO volume, retrograde operators (ROs) (>75 total CTO PCI cases and >20 retrograde attempts during the study period) and lower CTO volume, nonretrograde operators (NROs) to evaluate the impact of CTO-specific operator case volume and retrograde techniques on procedural outcomes. RESULTS:Two operators met the criteria for RO category and 10 were NRO. ROs performed 395 CTO PCI cases (mean total CTO case experience = 197.5, 60 retrograde) and NROs performed 241 CTO PCI cases (mean total CTO case experience = 24.1, <1 retrograde) during the observed timeframe. The overall technical success was 58.9% for NROs and 75.2% for ROs (p < 0.0001). The technical success rate of NROs did not change, but the technical success for the ROs increased to 90% over time (p < 0.0001 for trend, 94.4% for retrograde and 85.7% for antegrade approaches). Observed major adverse events were similar between ROs and NROs. CONCLUSIONS:Complex antegrade and retrograde "Japanese style" PCI approaches can be applied in the U.S. practice environment with high technical success and low adverse event rates. Higher CTO-specific operator case volume is associated with improved technical success rates.

Transradial intervention (TRI) approach has emerged as an alternative and competitive method compared with transfemoral intervention (TFI) approach for percutaneous coronary intervention (PCI) in simple to complex coronary disease. TRI, when performed by operators experienced with this technique, appears to have comparable efficacy and procedural resource utilization compared with TFI. However, vascular access complications, specifically major and minor bleeding, can be reduced with TRI. Patients with acute myocardial infarction (AMI) are at the highest risk for periprocedural bleeding for a variety of reasons, and may derive the greatest benefit from TRI. This review article will discuss potential advantages for TRI in the setting of AMI, barriers, and development of a TRI AMI program.

OBJECTIVES/OBJECTIVE:The purpose of this study was to evaluate the time-dependent vascular and myocardial responses to a second-generation, small vessel (< or =2.5 mm) paclitaxel-eluting stent (PES) platform. BACKGROUND:Small caliber coronary vessels present complex challenges for percutaneous coronary intervention (PCI) and are associated with lower technical success and inferior long-term efficacy. A next-generation, highly deliverable PES may improve clinical outcomes in small vessels. METHODS:Sixty single stents were implanted in noninjured coronary arteries in 30 domestic swine (one TAXUS Liberté small vessel PES (svPES) and one Liberté small vessel bare metal stent (svBMS) in each animal). Ten animals each were allocated to 30-, 90-, and 180-day follow-up groups; final quantitative angiography and necropsy were performed. Samples of myocardium, liver, and kidney were processed and evaluated for pathology. Radiography and either histopathology or scanning electron microscopy were performed on all the explanted stented vessels. RESULTS:There were no stent-related deaths or downstream myocardial pathology. Both the svPES stent and its svBMS control demonstrated complete strut tissue coverage and complete endothelialization at all timepoints, and there was no evidence of macro- or microscopic thrombus or stent fracture. Medial smooth muscle cell content was markedly reduced in all the svPES groups compared with that in the svBMS controls. CONCLUSIONS:The small diameter paclitaxel-eluting TAXUS Liberté stent has a safe and predictable biologic vascular response in the noninjured swine model. This device warrants further investigation targeting the currently poorly met clinical need for small vessel PCI.

The purpose of this study was to determine the relative impact of gender and age on the development of contrast-induced acute kidney injury (CIAKI) after cardiac catheterization. CIAKI is a recognized complication of coronary angiography, but the relative impact of age strata and gender is not well understood. We prospectively enrolled 21,489 consecutive patients undergoing coronary angiography and stratified patients by age and gender into 4 age categories (<50, 51 to 64, 65 to 79, and >80 years). Of those 21,489 patients, 13,127 were included in the study. Men and women were compared within each age category for the development of CIAKI in the period after angiography. The incidence of postprocedural CIAKI and mortality rates among groups were compared. Rates of postcatheterization CIAKI were higher for women compared with men in the 65- to 79-year-old (14.5% vs 11.0%, p <0.001) and >80-year-old (18.7% vs 15.1%, p = 0.048) groups, but no differences were seen in the younger cohorts. In conclusion, geriatric women are at greatest risk for the development of CIAKI after angiography.

OBJECTIVES/OBJECTIVE: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 (> or =0.5 mg/dL increase in creatinine within 48 hr with return to normal within 2 weeks), and persistent renal dysfunction (> or =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.

BACKGROUND:Efficacy of cellular cardiomyoplasty seems to occur in a dose-related manner. However, the safety of multiple transendomyocardial transplantation procedures to administer high cell dosages has not been previously reported. The aims of this study were to assess the short- and intermediate-term results of a repeated cell administration strategy and evaluate the safety of an "off-the-shelf" allogeneic mesenchymal stem cell (MSC) source. METHODS:Porcine bone marrow-derived MSCs were culture-expanded through three cycles in vitro before transplantation. Yorkshire swine weighing 30-40 kg were allocated to receive the total dose during 1 injection procedure or divided over 2 procedures separated by 14 days, as follows: (i) 400x10(6) allogeneic MSC (n=5), (ii) 800x10(6) allogeneic MSC divided in 2 doses (n=5), (iii) cryopreservant vehicle containing 10% DMSO, 5% porcine serum and 85% PlasmaLyte A, 14 days apart (n=2), or (iv) sterile saline 14 days apart (n=2). During each procedure, twenty 0.5 ml aliquots of the assigned injectant were administered using the Stiletto Endocardial Direct Injection Catheter System, targeting at the left ventricular anterior, septal and lateral walls under fluoroscopy. Vital signs and electrocardiograms were recorded during the procedure and at 24 h. The animals were examined daily and cardiac enzymes were measured immediately post-procedure, and on days 1, 15 and 90. Necropsy and histopathology were performed at day 90. RESULTS:Mean transendocardial injection procedure time was 40+/-10 min. All ventricular target areas were accessed by the Stiletto system. Ventricular ectopic beats and/or non-sustained ventricular tachycardia associated with catheter contact or endomyocardial injections were observed in all cases. However, no sustained ventricular arrhythmia, anaphylaxis, or significant cardiac enzyme release was seen. One mortality resulted from air embolism during the procedure. All other swine survived from the time of recovery until planned sacrifice at day 90 and had normal physical examination findings. The 3-month histopathology showed no evidence of rejection, calcification, teratoma or myocardial infarction. CONCLUSION/CONCLUSIONS:Repeated endomyocardial transplantation of high dose, bone marrow-derived allogeneic cells appeared safe in a large animal, human surrogate model. Such cellular cardiomyoplasty strategy warrants further investigation.

OBJECTIVE:Determining renal resistive index (RI) in the setting of renal artery stenosis may predict which patients benefit from revascularization. Renal duplex ultrasonography (RDUS) is the traditional method of assessing RI, but it is not available in most invasive endovascular laboratories. Conversely, endovascular techniques to assess RI are available but not well validated. The primary goal was to determine if an invasive approach using an endovascular Doppler flow wire correlates with RI assessment using traditional noninvasive RDUS. METHODS:In a single-center prospective trial, patients were enrolled if they had known or suspected renovascular disease. A Doppler flow wire was placed in multiple segments of the renal artery, and peak (PSV) and end-diastolic velocities (EDV) were measured. RI was calculated using the formula: RI = [1 - (EDV/PSV)] x 100. Similarly, RI was also derived using standard RDUS. All patients underwent both RI techniques before any revascularization procedure. Secondary end points included assessing the correlation for pole-to-pole renal length assessment and PSV and EDV velocities using both invasive and noninvasive techniques. Pearson correlation coefficient calculations were used to determine degree of correlation. RESULTS:The study enrolled 20 patients, and 35 renal arteries were studied. Overall, Pearson correlation coefficient for invasive vs noninvasive RI assessment was 0.86 (95% confidence interval [CI], 0.73 to 0.93). The r values were 0.43 (95% CI, 0.11 to 0.67) for pole-to-pole renal length, 0.66 (95% CI, 0.54 to 0.76) for PSV, and 0.61 (95% CI, 0.48 to 0.72) for EDV determination. No major complications occurred during this study. Average time to perform invasive Doppler assessment was 10.4 +/- 7.4 minutes per artery. CONCLUSIONS:Invasive RI assessment using an endovascular flow wire technique correlates well with traditional noninvasive RDUS. A moderate statistical correlation also exists for pole-to-pole renal length, PSV, and EDV determinations. The procedure is safe and can be performed rapidly.