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T Bruce Ferguson

Publications and source records attributed to T Bruce Ferguson.

At least 19 recordsLinked to original sources
PubMed2006

Bedside tool for predicting the risk of postoperative dialysis in patients undergoing cardiac surgery.

BACKGROUND: Estimation of an individual patient's risk for postoperative dialysis can support informed clinical decision making and patient counseling. METHODS AND RESULTS: To develop a simple bedside risk algorithm for estimating patients' probability for dialysis after cardiac surgery, we evaluated data of 449,524 patients undergoing coronary artery bypass grafting (CABG) and/or valve surgery and enrolled in >600 hospitals participating in the Society of Thoracic Surgeons National Database (2002-2004). Logistic regression was used to identify major predictors of postoperative dialysis. Model coefficients were then converted into an additive risk score and internally validated. The model also was validated in a second sample of 86,009 patients undergoing cardiac surgery from January to June 2005. Postoperative dialysis was needed in 6451 patients after cardiac surgery (1.4%), ranging from 1.1% for isolated CABG procedures to 5.1% for CABG plus mitral valve surgery. Multivariable analysis identified preoperative serum creatinine, age, race, type of surgery (CABG plus valve or valve only versus CABG only), diabetes, shock, New York Heart Association class, lung disease, recent myocardial infarction, and prior cardiovascular surgery to be associated with need for postoperative dialysis (c statistic=0.83). The risk score accurately differentiated patients' need for postoperative dialysis across a broad risk spectrum and performed well in patients undergoing isolated CABG, off-pump CABG, isolated aortic valve surgery, aortic valve surgery plus CABG, isolated mitral valve surgery, and mitral valve surgery plus CABG (c statistic=0.83, 0.85, 0.81, 0.75, 0.80, and 0.75, respectively). CONCLUSIONS: Our study identifies the major patient risk factors for postoperative dialysis after cardiac surgery. These risk factors have been converted into a simple, accurate bedside risk tool. This tool should facilitate improved clinician-patient discussions about risks of postoperative dialysis.

Aged↗
PubMed2006

Acute clopidogrel use and outcomes in patients with non-ST-segment elevation acute coronary syndromes undergoing coronary artery bypass surgery.

OBJECTIVES: We sought to characterize patterns of clopidogrel use before coronary artery bypass grafting (CABG) and examine the drug's impact on risks for postoperative transfusions among patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS). BACKGROUND: Adherence in community practice to American College of Cardiology/American Heart Association guidelines for clopidogrel use among NSTE ACS patients has not been previously characterized. METHODS: We evaluated 2,858 NSTE ACS patients undergoing CABG at 264 hospitals participating in the CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the ACC/AHA Guidelines) Initiative. We examined the patterns of acute clopidogrel therapy and its association with bleeding risks among those having "early" CABG < or =5 days and again among those having "late" surgery >5 days after catheterization. RESULTS: Within 24 h of admission, 852 patients (30%) received clopidogrel. In contrast to national guidelines, 87% of clopidogrel-treated patients underwent CABG < or =5 days after treatment. Among those receiving CABG within < or =5 days of last treatment, the use of clopidogrel was associated with a significant increase in blood transfusions (65.0% vs. 56.9%, adjusted odds ratio [OR] 1.36, 95% confidence interval [CI] 1.10 to 1.68) as well as the need for transfusion of > or =4 U of blood (27.7% vs. 18.4%, OR 1.70, 95% CI 1.32 to 2.19). In contrast, acute clopidogrel therapy was not associated with higher bleeding risks if CABG was delayed >5 days (adjusted OR 1.18, 95% CI 0.54 to 2.58). CONCLUSIONS: Despite guideline recommendations, the overwhelming majority of NSTE ACS patients treated with acute clopidogrel needing CABG have their surgery within < or =5 days of treatment. A failure to delay surgery is associated with increased blood transfusion requirements that must be weighed against the potential clinical and economic impacts of such delays.

Aged↗
PubMed2006

Contemporary performance of surgical ventricular restoration procedures: data from the Society of Thoracic Surgeons' National Cardiac Database.

BACKGROUND: Surgical ventricular restoration (SVR) is an operation that demonstrates promise to improve outcomes for patients with left ventricular dysfunction. Current use and operative outcomes of SVR have come from centers of expertise, and operative risks of SVR in community practice are unknown. We sought to characterize the performance of SVR nationally and describe the acute risks of mortality and major morbidity plus predictors of adverse outcomes. METHODS: We identified patients undergoing an SVR procedure at US hospitals participating in the Society of Thoracic Surgeons (STS) National Cardiac Database from January 2002 to June 2004. Baseline characteristics, operative characteristics, clinical outcomes, and predictors of adverse procedural outcomes were analyzed. RESULTS: There were 731 patients who underwent SVR at 141 of STS's 576 hospitals, and 20 centers performed 10 SVR procedures or more. The operative mortality was 9.3%; reoperation in 14.1%, stroke in 3.3%, renal failure in 8.1%, and prolonged ventilation in 21.5%. Combined death or major complications occurred in 33.5%. Major predictors of this combined end point were age, female sex, creatinine > or = 2 mg/dL, insulin-dependent diabetes, myocardial infarction within 1 week, history of congestive heart failure, 3-vessel coronary disease, severe mitral insufficiency, and status of surgery. CONCLUSION: This study provides a first look at use and outcomes of SVR in a national sample. Although a quarter of STS sites are performing SVR, most have limited experience and perioperative events are somewhat higher than prior selected series. Further studies of SVR are needed to improve patient selection and procedural performance.

Aged↗
PubMed2006

Racial and ethnic disparities in care: the perspectives of cardiovascular surgeons.

BACKGROUND: Although racial/ethnic disparities in care are well documented, particularly for cardiac care, we know little about what cardiac surgeons think about them. For educational efforts to be effective in helping physicians address disparities, they must consider providers' knowledge and beliefs about the underlying causes of the disparities. METHODS: We conducted a survey in 2004 to assess cardiologists' and cardiac surgeons' knowledge of racial/ethnic disparities in cardiovascular care and their perceptions about the underlying causes. Respondents were recruited from the membership of four cardiovascular professional associations. This paper focuses on cardiovascular surgeons' responses (n = 208). RESULTS: Forty-four percent of cardiovascular surgeons thought that, among patients with cardiac risk factors, black patients were not as likely as white patients to receive cardiac diagnostic tests and procedures. Additionally, 30% thought that black patients were not as likely as white patients to receive therapeutic tests and procedures. However, only 13% agreed that cardiac care disparities occur "often" or "somewhat often" based on patients' race/ethnicity, independent of their insurance and education. Only 3% thought disparities were likely to occur in their clinical setting. Respondents appeared more likely to endorse patient factors (eg, health behaviors or treatment adherence) than system or provider (eg, miscommunication or continuity of care) factors as reasons for disparities. CONCLUSIONS: Although some surgeons acknowledge that racial/ethnic disparities in cardiac care occur, very few agree that they occur often, independent of patients' characteristics. Educational efforts tailored to local care settings, such as reviewing quality of care data on patients of different races/ethnicities within a clinic/hospital, may effectively inform all physicians of these disparities.

Attitude of Health Personnel↗
PubMed2006

Trends in emergency coronary artery bypass grafting after percutaneous coronary intervention, 1994-2003.

BACKGROUND: In the last decade, percutaneous coronary intervention (PCI) has undergone profound changes in techniques used to achieve revascularization and in patient selection. We examine trends in emergency surgical revascularization after PCI. METHODS: Using The Society of Thoracic Surgeons National Cardiac Surgery Database, we examined patients undergoing coronary artery bypass grafting within 6 hours of PCI from 1994 to 2003. Stratifying into groups of patients who had and had not suffered myocardial infarction within 24 hours of PCI followed by coronary artery bypass grafting (CABG), we tracked trends in characteristics, predicted risk, and clinical outcomes. RESULTS: The proportion of isolated CABG procedures done emergently after PCI decreased over 1994 to 1999 from 3,357 of 115,679 (2.9%) to 1,227 of 155,831 (0.8%), remaining stable through 2003. Those suffering myocardial infarction within 24 hours made up a constant proportion of isolated CABG as emergency after PCI (3,352 of 1,042,864; 0.3%) since 1997. Over the decade, the preoperative risk profile worsened, including more elderly patients and more with cerebrovascular disease and congestive heart failure. Operative mortality among these patients has risen with time (from 8.0% to 9.3%; p < 0.0001 for trend), particularly in the setting of acute myocardial infarction (from 14.1% to 16.6%; p < 0.0001 for trend). Similarly, postoperative complications have increased over time, most notably seen in the need for reoperation (10.62% to 24.56%), prolonged postoperative ventilation (25.65% to 54.58%), and renal failure (10.22% to 18.55%). CONCLUSIONS: In 2005, there remains a low but real need for emergent CABG after PCI, in which operative outcomes are less than ideal, especially in the postinfarction patient, representing an area for cross-specialty collaboration.

Angioplasty, Balloon, Coronary↗
PubMed2006

Invited commentary.

Explore the source record for details and available documents.

Atrial Fibrillation↗
PubMed2006

Development of a human cardiac tissue-based angiogenesis model.

BACKGROUND: Previous angiogenesis models use animal tissues such as the chicken chorioallantoic membrane (CAM) or the rabbit cornea. These models may not accurately reflect the mechanisms responsible for human angiogenesis. MATERIALS AND METHODS: We hypothesized that fragments of human myocardial tissue would develop an angiogenic response from the cut edges of vessels contained within the tissue. To test these hypotheses, we obtained human atrial appendage tissue at the time of cardiac bypass. Fragments of atrial tissue were then incorporated into fibrin thrombin clots. Tissue fragments were observed, and the percent of wells that developed neovessel invasion into the clot was calculated (%I). The subsequent growth of cardiac-derived microvessels was rated and scored over time (Angiogenic Index). RESULTS: There were 20 human atrial appendages plated (n = 24 to 60 wells/specimen) and evaluated in this model. Out of the 20, 16 (80%) atrial appendages developed an angiogenic response in the majority (>50%) of wells plated. Neovessel growth was progressive over 14 to 16 days in culture in all specimens tested. The mean angiogenic index of all specimens was 8.59 +/- 0.91. CONCLUSIONS: This human cardiac tissue-based assay might be useful to screen compounds designed for use in human trials or provide highly vascularized cardiac tissue for autotransplantation. Additionally, the assay provides the foundation to study an individual patent's cardiac tissue and its response to angiogenesis stimulators or inhibitors. This may allow the development of patient-specific therapies designed to enhance revascularization or repair of injured cardiac muscle.

Cell Division↗
PubMed2006

Determinants of operative mortality in valvular heart surgery.

OBJECTIVE: In some respects, outcome reporting in valvular surgery has been hampered by focusing on specific populations, reluctance to publish high-risk subgroups, and possibly skewed or inadequate samples. The goal of this study was to evaluate risk factors for operative mortality comprehensively across the entire spectrum of cardiac valvular procedures over the past decade. METHODS: All 409,904 valve procedures in the Society of Thoracic Surgeons database performed between 1994 and 2003 were assessed, and Society of Thoracic Surgeons preoperative and operative variables were related to operative mortality by using a multivariable logistic regression model. Data were greater than 95% complete, and the relative importance of relevant risk factors was determined by ranking odds ratios. The analysis had a high predictive power, with a C statistic of 0.735. RESULTS: In the model, 19 variables independently influenced operative mortality (all P < .01). The most significant was nonelective (acute) presentation (odds ratios, 2.11), followed by advanced age (odds ratios, 1.88), reoperation (odds ratios, 1.61), endocarditis (odds ratios, 1.59), and coronary disease (odds ratios, 1.58). Generally, valve replacement was associated with higher mortality than repair (odds ratios, 1.52). Overall, female gender was very important (odds ratios, 1.37), and earlier year of operation increased risk (odds ratios, 1.34), implying improving outcomes over time. Although any single comorbidity, on average, was only moderately contributory (odds ratios, 1.19), specific comorbidities, such as renal failure, or multiple comorbidities in a given patient could be very significant. Aortic root reconstruction carried the highest risk (odds ratios, 2.78), followed by tricuspid valve surgery (odds ratios, 2.26), multiple valve procedures (odds ratios, 2.06), and then isolated mitral (odds ratios, 1.47), pulmonic (odds ratios, 1.29), and aortic (reference procedure) operations. Reduced ejection fraction and severity of valve lesion were relatively less important (odds ratios, 1.34 and 0.83, respectively). CONCLUSIONS: These data illustrate the significance of acute presentation in determining operative risk, and earlier surgical intervention under elective conditions might be emphasized for all types of significant valve lesions. Because aortic root reconstruction doubles mortality compared with simple aortic valve procedures, root replacement should be reserved for specific root pathology. Finally, issues related to reoperation, endocarditis, valve repair, gender, and the various procedures deserve more detailed examination.

Aged↗
PubMed2005

Efficacy and safety of edifoligide, an E2F transcription factor decoy, for prevention of vein graft failure following coronary artery bypass graft surgery: PREVENT IV: a randomized controlled trial.

CONTEXT: Coronary artery bypass graft (CABG) surgery with autologous vein grafting is commonly performed. Progressive neointimal hyperplasia, however, contributes to considerable vein graft failure. Edifoligide is an oligonucleotide decoy that binds to and inhibits E2F transcription factors and thus may prevent neointimal hyperplasia and vein graft failure. OBJECTIVE: To assess the efficacy and safety of pretreating vein grafts with edifoligide for patients undergoing CABG surgery. DESIGN, SETTING, AND PARTICIPANTS: A phase 3 randomized, double-blind, placebo-controlled trial of 3014 patients undergoing primary CABG surgery with at least 2 planned saphenous vein grafts and without concomitant valve surgery, who were enrolled between August 2002 and October 2003 at 107 US sites. INTERVENTION: Vein grafts were treated ex vivo with either edifoligide or placebo in a pressure-mediated delivery system. The first 2400 patients enrolled were scheduled for 12- to 18-month follow-up angiography. MAIN OUTCOME MEASURES: The primary efficacy end point was angiographic vein graft failure (> or =75% vein graft stenosis) occurring 12 to 18 months after CABG surgery. Other end points included other angiographic variables, adverse events through 30 days, and major adverse cardiac events. RESULTS: A total of 1920 patients (80%) either died (n = 91) or underwent follow-up angiography (n = 1829). Edifoligide had no effect on the primary end point of per patient vein graft failure (436 [45.2%] of 965 patients in the edifoligide group vs 442 [46.3%] of 955 patients in the placebo group; odds ratio, 0.96 [95% confidence interval {CI}, 0.80-1.14]; P = .66), on any secondary angiographic end point, or on the incidence of major adverse cardiac events at 1 year (101 [6.7%] of 1508 patients in the edifoligide group vs 121 [8.1%] of 1506 patients in the placebo group; hazard ratio, 0.83 [95% CI, 0.64-1.08]; P = .16). CONCLUSIONS: Failure of at least 1 vein graft is quite common within 12 to 18 months after CABG surgery. Edifoligide is no more effective than placebo in preventing these events. Longer-term follow-up and additional research are needed to determine whether edifoligide has delayed beneficial effects, to understand the mechanisms and clinical consequences of vein graft failure, and to improve the durability of CABG surgery. Clinical Trial Registration ClinicalTrials.gov Identifier: NCT00042081.

Aged↗
PubMed2005

Clinical predictors of major infections after cardiac surgery.

BACKGROUND: Major infections are infrequent but important complications of cardiac surgery. Predicting their occurrence is essential for future prevention. The objective of the current investigation was to create and validate a bedside scoring system to estimate patient risk for major infection (mediastinitis, thoracotomy or vein harvest site infection, or septicemia) after coronary artery bypass grafting. METHODS AND RESULTS: Using the Society of Thoracic Surgeons National Cardiac Database, we analyzed 331 429 coronary artery bypass grafting cases from January 1, 2002, to December 31, 2003, to identify risk factors for major infection. Using logistic regression, 2 models were generated and validated using split-sample validation: (1) One limited to preoperative characteristics (preop model) and (2) one model including both preoperative and intraoperative characteristics (combined model). Major infection occurred in 11 636 patients (3.51%) (25.1% mediastinitis, 32.6% saphenous harvest site, 35.0% septicemia, 0.5% thoracotomy, 6.8% multiple sites). Patients with major infection had significantly higher mortality (17.3% versus 3.0%, P<0.0001) and postoperative length of stay >14 days (47.0% versus 5.9%, P<0.0001) than patients without major infection. Both the preop model (c-index 0.697) and combined model (c-index: 0.708) successfully discriminated between high- and low-risk patients. A simplified risk scoring system of 12 variables accurately predicted risk for major infection. CONCLUSIONS: We identified and validated a model that can identify patients undergoing cardiac surgery who are at high risk for major infection. These high-risk patients may be targeted for perioperative intervention strategies to reduce rates of major infection.

Aged↗
PubMed2005

Comparing on-pump and off-pump coronary artery bypass grafting: numerous studies but few conclusions: a scientific statement from the American Heart Association council on cardiovascular surgery and anesthesia in collaboration with the interdisciplinary working group on quality of care and outcomes research.

One of the most hotly debated and polarizing issues in cardiac surgery has been whether coronary artery bypass grafting (CABG) without the use of cardiopulmonary bypass or cardioplegia (off-pump CABG, or OPCAB) is superior to that performed with the heart-lung machine and the heart's being chemically arrested (standard CABG). Various clinical trials are reviewed comparing the 2 surgical strategies, including several large retrospective analyses, meta-analyses, and the randomized trials that address different aspects of standard CABG and OPCAB. Although definitive conclusions about the relative merits of standard CABG and OPCAB are difficult to reach from these varied randomized and nonrandomized studies, several generalizations may be possible. Patients may achieve an excellent outcome with either type of procedure, and individuals' outcomes likely depend more on factors other than whether they underwent standard CABG or OPCAB. Nevertheless, there appear to be trends in most studies. These trends include less blood loss and need for transfusion after OPCAB, less myocardial enzyme release after OPCAB up to 24 hours, less early neurocognitive dysfunction after OPCAB, and less renal insufficiency after OPCAB. Fewer grafts tend to be performed with OPCAB than with standard CABG. Length of hospital stay, mortality rate, and long-term neurological function and cardiac outcome appear to be similar in the 2 groups. To definitively answer the remaining questions of whether either strategy is superior and in which patients, a large-scale prospective randomized trial is required.

American Heart Association↗
PubMed2005

Racial and ethnic disparities in care: the perspectives of cardiologists.

BACKGROUND: Despite extensive documentation of racial and ethnic disparities in care, provider awareness of disparities has been thought to be low. To be effective, educational efforts for physicians must consider providers' knowledge and beliefs about what causes disparities and what can be done about them. METHODS AND RESULTS: We conducted a Web-based survey of 344 cardiologists to determine their level of awareness of disparities and views of underlying causes. Responses were assessed by means of 5-point Likert scales. Thirty-four percent of cardiologists agreed that disparities existed in care overall in the US healthcare system, and 33% agreed that disparities existed in cardiovascular care. Only 12% felt disparities existed in their own hospital setting, and even fewer, 5%, thought disparities existed in the care of their own patients. Despite this, most respondents rated the strength of the evidence about disparities as "very strong" or "strong." Respondents identified many potential causes for disparities in care but were more likely to endorse patient and system level factors (eg, insurance status or adherence) rather than provider level factors. CONCLUSIONS: Cardiologists' awareness of disparities in care remains low, and awareness is inversely proportional to proximity to their own practice setting.

Adult↗
PubMed2005

The PRoject of Ex-vivo Vein graft ENgineering via Transfection IV (PREVENT IV) trial: study rationale, design, and baseline patient characteristics.

BACKGROUND: Coronary artery bypass graft (CABG) surgery with autologous vein graft (VG) conduit is one of the most frequently performed operations in the United States. Unfortunately, many VGs become occluded during long-term follow-up largely because of neointimal hyperplasia. A novel approach to preventing neointimal hyperplasia is with the double-stranded oligonucleotide edifoligide (Corgentech Inc, South San Francisco, Calif). Edifoligide inhibits E2F, a transcription factor that activates cell-cycle genes responsible for neointimal hyperplasia. METHODS: PREVENT IV is a phase-III, multicenter, randomized double-blind placebo-controlled trial of ex vivo treatment of autologous VGs with edifoligide in patients undergoing initial CABG surgery. The primary end point is VG failure, defined as death or > or =75% stenosis in a treated VG at 12- to 18-month angiographic follow-up. Secondary end points include major adverse cardiac events through at least 5 years and adverse events through 30 days. RESULTS: Enrollment of 3014 patients from 107 sites was completed on October 22, 2003. The baseline and procedural characteristics of the PREVENT IV population are generally well matched to a contemporary population of patients undergoing initial CABG from the Society of Thoracic Surgeons National Database. Angiographic follow-up is ongoing and scheduled to be completed in March 2005. CONCLUSIONS: The PREVENT IV data will establish whether VG pretreatment with an E2F transcription factor decoy, edifoligide, can improve graft patency and reduce the long-term morbidity and mortality of patients undergoing CABG surgery.

Aged↗
PubMed2005

Impact of unstable angina on outcomes of transmyocardial laser revascularization combined with coronary artery bypass grafting.

BACKGROUND: For sole therapy transmyocardial laser revascularization (TMR), unstable angina has been demonstrated to be a significant independent predictor of operative mortality. The objective of this study was to investigate the preoperative risk profile of patients undergoing TMR plus coronary artery bypass graft surgery (CABG) and to determine the impact of unstable angina on outcomes. METHODS: Using The Society of Thoracic Surgeons National Cardiac Database from 1998 to 2003, 5,618 patients underwent TMR plus CABG. These patients were compared with 932,715 patients who underwent CABG only operations. RESULTS: The TMR plus CABG patients had a significantly higher incidence of diabetes (50% versus 34%), renal failure (7% versus 5%), peripheral vascular disease (20% versus 16%), reoperative surgery (26% versus 9%), three-vessel coronary artery disease (80% versus 71%), hyperlipidemia (73% versus 62%; p < 0.001 for all comparisons). The incidence of preoperative unstable angina was similar (46% versus 47%). The unadjusted perioperative mortality was 3.8% for TMR plus CABG patients. When unstable angina patients were removed, the observed mortality for TMR plus CABG was decreased to 2.7%. CONCLUSIONS: It is likely that patients who undergo TMR plus CABG have a higher prevalence of diffuse coronary disease based on their preoperative demographics. Despite the increased risk associated with such anatomy, the mortality rate was not significantly increased when TMR was added to CABG in an effort to provide a more complete revascularization. As was noted from the outcomes of sole therapy TMR, in unstable angina patients, TMR plus CABG carries a higher risk, but this risk is not significantly different from that of such patients treated with CABG alone.

Angina, Unstable↗
PubMed2005

Direct visualization of coronary sinus ostium and branches with a flexible steerable fiberoptic infrared endoscope.

BACKGROUND: Placement of electrophysiology catheters and pacing leads in the coronary sinus is challenging in some patients, particularly those with dilated cardiomyopathy. We hypothesized that cannulation of the coronary sinus and its branches can be facilitated by direct visualization. This study reports our experience with navigation into and within the coronary sinus in a closed-chest animal preparation, using a flexible steerable fiberoptic infrared endoscope that allows visualization through flowing blood. OBJECTIVES: The purpose of this study was to assess the feasibility of direct visualization of endocardial structures through infrared endoscopy. METHODS: Internal jugular venous access was obtained in 10 healthy mongrel dogs (weight 35-45 kg). The infrared endoscope (2900 fiber imaging bundle, wavelength 1,620 nm, frame rate 10-30/s, 320 x 256 pixels) was advanced to the coronary sinus ostium and branches by direct visualization of anatomic landmarks, such as the tricuspid valve and inferior vena cava. Localization was confirmed by fluoroscopy, contrast injection, and pathologic examination. RESULTS: Structures such as the tricuspid valve and inferior vena cava were visualized at distances of 1 to 2 cm, allowing successful coronary sinus identification and engagement in all 10 dogs. Coronary sinus branch images closely resembled pathologic findings. CONCLUSION: Direct visualization of the coronary sinus ostium and branches is possible through infrared endoscopy. This technique likely will facilitate coronary sinus engagement and navigation for pacing lead and catheter placement.

Angioscopy↗
PubMed2005

Direct imaging of transvenous radiofrequency cardiac ablation using a steerable fiberoptic infrared endoscope.

BACKGROUND: Direct imaging through blood has been achieved in vivo using fiberoptics and infrared wavelength technology. OBJECTIVES: The purpose of this study was to determine the feasibility of using a percutaneous, steerable, fiberoptic infrared endoscope to identify and characterize the electrode-tissue interface during transvenous cardiac ablation. METHODS: Infrared endoscopy was performed during 24 catheter ablation attempts in 10 mongrel dogs. Infrared imaging was performed through a transparent dome located at the tip of a 7Fr steerable endoscope using an imaging wavelength of 1,620 nm. Radiofrequency ablation was performed using a 4-mm-tip electrode catheter. Attempts were made to identify the electrode-endocardial interface at each ablation site and to characterize any signal changes during ablation. RESULTS: The electrode-tissue interface could be identified at 19 of the 24 ablation sites. Changes at the electrode-tissue interface were observed during ablation at 14 sites, which included a gradual increase in the tissue signal intensity at 12 sites. Small lucencies near the ablation electrode were observed at six sites. There was no interference during energy delivery. Endocardial features identified by endoscopy correlated with the postmortem appearance. CONCLUSION: Direct imaging of intracardiac structures and the electrode-tissue interface can be achieved through blood during transvenous catheter ablation with infrared endoscopy using a steerable, fiberoptic, infrared endoscopic catheter. Ablation lesion formation can be seen as a gradual increase in signal intensity. Fiberoptic infrared endoscopy appears to be a promising new tool for guiding catheter ablation.

Animals↗