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Biomedical subjects

Michael Argenziano

Publications and source records attributed to Michael Argenziano.

At least 19 recordsLinked to original sources

Minimally invasive versus standard approach for excision of atrial masses.

BACKGROUND: Minimally invasive cardiac surgical procedures have become ubiquitous over the past decade. In many cases, these techniques have been associated with decreased morbidity, shorter length of stay, decreased pain, faster recovery, and superior cosmetic results. The purpose of this study was to compare outcomes using a minimally invasive (mini-thoracotomy) versus standard (sternotomy) approach to the surgical resection of atrial masses. METHODS: Analysis was based on 34 consecutive patients who underwent atrial mass resection at the New York-Presbyterian Hospital/Columbia Presbyterian Medical Center in New York, NY. The reference (REF) group included 18 patients who underwent excision of an atrial mass via a standard approach (sternotomy). The minimally invasive (MI) group included 16 patients who underwent excision of an atrial mass via a mini-thoracotomy. RESULTS: There were no statistically significant differences between the REF and MI groups based on demographic or preoperative characteristics. Tissue diagnosis of the masses resected included myxoma (n = 24), fibroblastoma (n = 3), B-cell lymphoma (n = 1), and other benign masses (n = 6). Cardiopulmonary bypass (70.5 versus 76.5 minutes; P = .57) and aortic cross-clamp times (32.7 versus 47.3 minutes; P = .14) did not differ significantly between the REF and MI groups, nor did intraoperative transfusion of packed red blood cells (0.35 versus 0.38 units; P = .93). As assessed by intraoperative trans-esophageal echocardiogram, there were no moderate to severe valvular abnormalities observed following chest closure. Intensive care unit length of stay (46.1 versus 26.2 hours; P = .15), overall hospital length of stay (6.39 versus 5.06 days; P= .18), and time to extubation (0.78 versus 0.44 days; P = .44) all trended toward shorter duration in the MI group compared with the REF group-although none of these differences achieved statistical significance. Postoperative transthoracic echocardiograms were obtained in 14 of 34 (41.2%) patients; none revealed any new or significant abnormalities. All patients survived to hospital discharge; one patient in the REF group expired during the follow-up period. Among the 34 patients, 26 patients (76.4%) were at least 2 years postoperative from their resection; 25 of the 26 (96.1%) were alive at 2-year follow-up, and the remaining 8 were alive at 1-year follow-up. All patients were free of recurrence at last follow-up. CONCLUSIONS. Minimally invasive atrial mass excisions can be accomplished reliably without compromising complete tumor resection and without significant increases in operative times or serious adverse events. In addition, measures of recovery time in this study suggest faster recovery among the MI group, which is consistent with the proposed advantages by proponents of minimally invasive surgery.

Adult↗

Survival after heart transplantation is not diminished among recipients with uncomplicated diabetes mellitus: an analysis of the United Network of Organ Sharing database.

BACKGROUND: This study compares posttransplantation outcomes of survival and morbidity among recipients with and without diabetes mellitus (DM). METHODS AND RESULTS: The United Network of Organ Sharing (UNOS) provided deidentified patient-level data. Primary analysis focused on 20,412 first-time heart transplant recipients aged > or = 18 years who underwent transplantation between January 1, 1995, and December 31, 2005. To determine severity of DM, DM recipients were stratified by their aggregate number of diabetes-related complications (DRCs), including pretransplantation history of renal failure (serum creatinine = 2.5 mg/dL), peripheral vascular disease, cerebrovascular accident, and severe obesity (body mass index > or = 35 kg/m2). Kaplan-Meier analysis was performed to compare time to event. Although posttransplantation survival was significantly better (P<0.001) among patients without DM (median survival 10.1 years) than among those with DM (9.0 years), survival did not differ (P=0.08) between those without DM (10.1 years) and those with uncomplicated DM (0 DRCs; 9.3 years). Among those with DM, survival was worse with each additional DRC: 0 DRC, 9.3 years; 1 DRC, 6.7 years; and > or = 2 DRCs, 3.6 years. Although acute rejection and transplant coronary artery disease-free survival did not differ between groups, renal failure and severe infection-free survival were worse in those with DM and were inversely related to the number of DRCs. CONCLUSIONS: Posttransplantation survival among patients with uncomplicated DM was not significantly different than that among nondiabetics. However, when stratified by disease severity, recipients with more severe diabetes had significantly worse survival than nondiabetics. Therefore, although DM alone should not be a contraindication to heart transplantation, given the critical shortage of transplantable organs, maximal benefit may be achieved by exploring alternative treatment options in patients with severe DM. These include use of high-risk transplant lists and destination therapy.

Adult↗

Results of the prospective multicenter trial of robotically assisted totally endoscopic coronary artery bypass grafting.

BACKGROUND: Robotic technology has been proven safe and efficacious in the performance of mitral valve repair and atrial septal defect repair. This report describes a Food and Drug Administration-sanctioned multicenter study of the safety and efficacy of the da Vinci system (Intuitive Surgical, Inc, Mountain View, CA) for totally endoscopic coronary artery bypass (TECAB) surgery. METHODS: Patients requiring left anterior descending (LAD) coronary artery revascularization were eligible. The procedure was performed with femoro-femoral cardiopulmonary bypass (CPB), endoaortic balloon occlusion, and thoracoscopy. All aspects of the procedure were performed with the robotic system, from internal mammary artery harvest to coronary anastomosis. RESULTS: Ninety-eight patients requiring single-vessel LAD revascularization were enrolled at 12 centers. Thirteen patients (13%) were excluded intraoperatively (eg, failed femoral cannulation, inadequate working space). In 85 patients (69 men, age 58 +/- 10 years) who underwent TECAB, CPB time was 117 +/- 44 minutes, cross-clamp time was 71 +/- 26 minutes, and hospital length of stay was 5.1 +/- 3.4 days. There were five (6%) conversions to open techniques. There were no deaths or strokes, one early reintervention, and one myocardial infarction (1.5%). Three-month angiography was performed in 76 patients, revealing significant anastomotic stenoses (> 50%) or occlusions in 6 patients. Overall freedom from reintervention or angiographic failure was 91%. CONCLUSIONS: Robotic TECAB was accomplished with no mortality, low morbidity, and angiographic patency and reintervention rates comparable with published data. Although the use of CPB was a limitation of the technique, this experience represents a step toward more advanced procedures, such as multivessel or off-pump TECAB.

Adult↗

Laser energy source in surgical atrial fibrillation ablation: preclinical experience.

PURPOSE: The purpose of this study was to evaluate diffusing tip laser energy in surgical atrial fibrillation ablation using a canine model. This is the first report to describe the pathological and histological findings using a laser energy source. DESCRIPTION: The surgical atrial fibrillation ablation procedure was performed through a left atriotomy; the pulmonary veins were encircled in 16 dogs using a diode laser (980 nm) with a diffusing tip that permits linear ablation perpendicular to the fiber direction. Lesion durations were 45 seconds with a power density of 3.8 or 4.5 W/cm. Six animals were allowed to survive 4 hours after the procedure, with the remainder sacrificed at 1 week (n = 1), 4 weeks (n = 3), and 6 weeks (n = 6). Electrophysiologic effectiveness was judged using unipolar or bipolar pacing from the pulmonary veins after attempting isolation. Hearts were harvested for histologic examination using standard trichrome staining. EVALUATION: All animals tolerated the procedure. The animals required an average of 5.6 +/- 0.82 lesions to complete the procedure. All animals had confirmed isolation of the pulmonary veins as judged by unipolar or bipolar pacing, and this isolation persisted in those animals that were allowed to survive. Pathology revealed all lesions to be transmural with an average tissue thickness of 3.62 +/- 1.50 mm (range, 0.95 mm to 7.06 mm). CONCLUSIONS: Diffusing tip laser technology reproducibly makes rapid, transmural, and electrophysiologically effective atrial lesions.

Animals↗

Mechanisms of atrial tachyarrhythmias following surgical atrial fibrillation ablation.

INTRODUCTION: Typical and atypical atrial flutters (AFLs) and atrial tachycardias (ATs) have been reported in patients with prior surgical atrial fibrillation ablation. The underlying mechanisms for this group of atrial tachyarrhythmias have not been well characterized and the efficacy of catheter ablation in their treatment is unknown. METHODS AND RESULTS: Twenty patients (6 females) with a surface ECG diagnosis of AFL or AT following surgical atrial fibrillation ablation underwent 26 electrophysiology studies. Patients manifesting sustained, organized, and beat-by-beat reproducible atrial electrical activity underwent complete right and left atrial catheter mapping and catheter ablation. One patient had no inducible tachyarrhythmia, while 5 patients had nonmappable arrhythmias. Nineteen of the 31 potentially mappable atrial tachyarrhythmias were completely characterized in 14 patients. The underlying mechanisms were macro-reentrant left AFL (n = 9), focal left AT (n = 3), typical right AFL (n = 6), and atypical right AFL (n = 1). Of the 19 completely characterized atrial arrhythmias, catheter ablation was performed for 18, and the procedure was successful for 13 of these. After a mean follow-up of 15 +/- 10 months, 15 of 20 patients (75%) were in sinus rhythm including 10 of 13 patients (77%) with AT/flutter ablation. Ten patients, including 6 following ablation, were maintaining sinus rhythm without antiarrhythmic medications. CONCLUSIONS: Patients with an ECG diagnosis of AFL or AT following surgical atrial fibrillation ablation may have multiple tachycardia mechanisms with the right or left atrium as the site of origin. Many of these rhythms may resolve with further maturation of surgical atrial fibrillation ablation (SAFA) lesions or be treatable with antiarrhythmic medication. However, persistent tachyarrhythmias can often be treated successfully with catheter mapping and ablation.

Atrial Fibrillation↗

Radiofrequency and microwave energy sources in surgical ablation of atrial fibrillation: a comparative analysis.

BACKGROUND: Due to its complexity and risk of bleeding, the Maze III procedure has been largely replaced by surgical ablation for atrial fibrillation (AF) using alternative energy sources. Radiofrequency (RF) and microwave (MW) are the most commonly used energy forms. In this study, we sought to compare these energy modalities in terms of clinical outcomes. METHODS: Two hundred five patients underwent surgical ablation of AF, from October 1999 to May 2004 at our institution via an endocardial approach. Patients were categorized into 2 groups: RF and MW. Baseline characteristics, operative details, and clinical outcomes were compared between the 2 groups. Rhythm success was defined as freedom from AF and atrial flutter as determined by postoperative electrocardiograms. RESULTS: One hundred twenty patients (58.5%) were ablated using RF, whereas 85 (41.5%) were ablated with MW. Most of the patients had persistent AF in both the RF and MW groups (85.7% versus 80.0%, respectively; P = .363). Intraoperative left atrial size was 6.4 +/- 1.7 cm for the RF group and 6.4 +/- 1.7 cm for the MW group (P = .820). Postoperative rhythm success at 6 and 12 months was 72.4% versus 71.4% (P +/- .611) and 75.0% versus 66.7% (P = .909) for the RF and MW groups, respectively. Hospital length of stay was comparable for both groups (15.4 +/- 14.0 versus 13.3 +/- 13.9 days; P = .307). Postoperative survival at 6 months, 1 year, and 3 years was 90.4%, 89.5%, and 86.1% for RF patients compared to 87.9%, 86.5%, and 84.4% for MW patients, respectively (log rank P = .490). CONCLUSIONS: RF and MW energy forms yield comparable postoperative rhythm success, hospital length of stay, and postoperative survival. Both sources are rapid, safe, and effective alternatives to "cut and sew" techniques for surgical treatment of AF.

Atrial Fibrillation↗

Off-pump epicardial atrial fibrillation surgery utilizing a novel bipolar radiofrequency system.

BACKGROUND: Over the past several years, pulmonary vein isolation for the treatment of atrial fibrillation has gained significant popularity. This study was undertaken to evaluate a novel radiofrequency (RF)-enabled clamp system designed to create transmural lesions epicardially on the beating heart using bipolar RF. METHODS: A set of differently shaped clamps modified to deliver bipolar RF energy were used to create a series of lesions in a beating heart canine model. The pulmonary veins and atrial appendages of 6 dogs were electrically isolated using bipolar RF energy. The right and left atrial appendages served as controls for the right and left pulmonary veins, respectively. Temperature-controlled RF energy was delivered to maintain a tissue temperature of 80 degrees C for 15 seconds. Electrical isolation was assessed acutely and after 4 weeks by a bipolar pacing protocol. RESULTS: A total of 24 circumferential lesions were created. By pacing analysis, 100% (24/24) of these lesions were electrically isolated acutely and 95% (19/20) were still isolated 4 weeks later. At 4 weeks, 92% (22/24) of lesions were transmural by histologic analysis, and 96% (23/24) demonstrated endocardial continuity. One animal experienced a fatal cardiac arrhythmia during initiation of the post-survival procedure, prior to electrophysiologic evaluation, accounting for the reduced number of potential electrically isolated lesions. CONCLUSION: Bipolar RF ablation utilizing a novel bipolar RF clamp device results in electrical isolation and histologic transmurality in an off-pump epicardial model.

Animals↗

Epicardial cardiac ablation using laser energy.

We describe epicardial ablation using a new device that utilizes 980 nm wavelength laser energy. The device can be used in both open and minimally invasive approaches and should make ablation therapy safe, effective, and easy to use.

Cardiac Surgical Procedures↗

Coronary artery bypass grafting in patients with low ejection fraction.

BACKGROUND: Patients with low ejection fraction (EF) are at a higher risk for postoperative complications and mortality. Our objective was to assess the effect of low EF on clinical outcomes after coronary artery bypass grafting (CABG). METHODS AND RESULTS: We analyzed 55,515 patients from New York State database who underwent CABG between 1997 and 1999. Patients were stratified into 1 of the 4 EF groups: Group I (EF< or =20%), Group II (EF 21% to 30%), Group III (EF 31% to 40%), and Group IV (EF>40%). History of previous myocardial infarction, renal failure, and congestive heart failure were higher in patients with low EF (all P<0.001). Group I experienced a higher incidence of postoperative respiratory failure (10.1% versus 2.9%), renal failure (2.5% versus 0.6%), and sepsis (2.5% versus 0.6%) compared with Group IV. In-hospital mortality was significantly higher in Group I (6.5% versus 1.4%; P<0.001). Multivariate analysis showed hepatic failure [odds ratio (OR), 11.2], renal failure (OR, 4.1), previous myocardial infarction (OR, 3.4), reoperation (OR, 3.4), emergent procedures (OR, 3.2), female gender (OR, 1.7), congestive heart failure (OR, 1.6), and age (OR, 1.04) as independent predictors of in-hospital mortality in the low EF group. The discharges to home rate were significantly lower in Group I versus Group IV (73.1% and 87.7%, respectively; P<0.001). CONCLUSIONS: Patients with low EF are sicker at baseline and have >4 times higher mortality than patients with high EF. However, outcomes are improving over time and are superior to historical data. Therefore, CABG remains a viable option in selected patients with low EF.

Aged↗

A decade experience of cardiac retransplantation in adult recipients.

BACKGROUND: Cardiac retransplantation is considered to be the best therapeutic option for a failing cardiac allograft. However, poor outcomes with retransplantation have previously been reported, a factor that raises important ethical, logistic and financial issues given the limited organ donor supply. METHODS: Seven hundred sixty-six adult patients underwent cardiac transplantation for end-stage heart failure at our institution from 1992 to 2002. Of these, 41 (5.4%) were retransplants. Variables examined included recipient and donor demographics, indications for retransplant, comorbidities, cytomegalovirus (CMV) serology status, left ventricular assist device use before transplant, donor ischemic time, rate of early mortality (within 30 days), and post-transplantation survival rate. RESULTS: Indications for cardiac retransplant were transplant-related coronary artery disease in 37, acute rejection in 3, and other causes in 1. The mean interval between transplantation and retransplantation was 5.9 +/- 3.4 years. Baseline characteristics such as recipient age, gender, CMV serology status, and donor age were similar in the primary transplant and retransplant groups. Early mortality after transplantation was comparable between the 2 groups, but post-transplant survival was significantly lower in retransplant patients compared with primary transplants with 1-, 3-, 5-, and 7-year actuarial survival rates of 72.2%, 66.3%, 47.5%, and 40.7% vs. 85.1%, 79.2%, 72.9%, and 66.8%, respectively (p < 0.001). CONCLUSIONS: Cardiac retransplantation offers short-term outcomes similar to primary transplantation but lower long-term survival rates. Non-retransplant surgical options should also be considered in these patients. Careful patient selection and risk-assessment is necessary to govern appropriate allocation of limited donor organs.

Adult↗

Adhesiolysis is facilitated by robotic technology in reoperative cardiac surgery.

Over a 2-year period, 5 patients who required reoperative chest surgery underwent robotic adhesiolysis with the da Vinci (Intuitive, Sunnyvale, CA) system. Resternotomy was performed under direct visualization for coronary revascularization (n = 2) or valve replacement (n = 1). A fourth patient required coronary revascularization after a previous axilloaxillary bypass. The final case involved the preparation of a substernal pathway for a gastric pull-up. In all cases adhesions were taken down without injury to the underlying structures. All grafts were preserved, and all patients recovered uneventfully. Robotic adhesiolysis is a versatile technique that allows careful lysis of adhesions and minimizes the risk of major complication during reoperative chest surgery.

Adult↗

Surgical revision after percutaneous mitral valve repair with a clip: initial multicenter experience.

PURPOSE: Almost 50,000 mitral valve operations are performed annually in the United States, with an increasing number of repairs. Recently, a percutaneous mitral valve repair option that achieves edge-to-edge approximation with a clip has been described in patients with mitral regurgitation. DESCRIPTION: We describe 6 patients from three centers with mitral regurgitation after percutaneous repair who underwent reintervention. During open surgical revision, the clips were uneventfully removed in all patients with no limitation in surgical options. Five patients underwent repair and 1 underwent replacement. EVALUATION: After surgical revision, mitral regurgitation was significantly decreased, and all but 1 patient underwent uneventful recovery. One patient developed ilio-femoral deep venous thrombosis that was treated successfully with anticoagulation. CONCLUSIONS: Preserving standard of care options is critical with any evolving technology in the event of initial treatment failure. Standard surgical options were preserved in all of the patients who underwent percutaneous mitral valve edge-to-edge repair. Furthermore, a thorough understanding of the clip design, in particular its unlocking mechanism, is essential and facilitates surgical clip removal.

Adult↗

Thoracoscopic epicardial pulmonary vein ablation for lone paroxysmal atrial fibrillation.

Surgical treatment of atrial fibrillation recently gained new popularity since the introduction of different energy sources for ablative therapy as an alternative to the original "cut-and-sew" techniques. However, most of the cases have been performed together with other cardiac surgical procedures and mainly through a standard median sternotomy approach. We report here the first European case of closed-chest thoracoscopic pulmonary vein isolation in a patient with lone paroxysmal atrial fibrillation.

Atrial Fibrillation↗

Robotic techniques improve quality of life in patients undergoing atrial septal defect repair.

BACKGROUND: Minimally invasive cardiac surgery has emerged as an alternative to conventional, open surgery. Although most studies of robotically assisted cardiac surgery have reported morbidity and mortality, few have addressed outcome measures, such as pain and quality of life, which was the aim of this study. METHODS: Eleven patients with atrial septal defects (ASD), and five patients with patent foramen ovale, underwent repair using the Da Vinci system (Intuitive Surgical, Mountain View, CA). The Medical Outcomes Study Short Form Survey (SF-36), along with two additional questions, were administered to these patients on postoperative day 30, along with a similar number of patients who underwent ASD repair by mini-thoracotomy or sternotomy. Quality of life endpoints included bodily pain, vitality, mental health, general health, physical function, and social function. RESULTS: Robotic patients demonstrated significantly higher scores in 6 of the eight variables (p < 0.05). There was no significant difference in intensive care unit or overall hospital stay among the groups (p = NS). Robotic patients returned to work after 40.2 +/- 30.2 days, mini-thoracotomy patients after 45.6 +/- 27.9 days, and sternotomy patients after 51.7 +/- 40.2 days (p = 0.767). There were no significant differences in SF-36 scores between patients who underwent mini-thoracotomy and sternotomy approaches. CONCLUSIONS: Closure of an ASD can be performed safely and effectively via an endoscopic approach. Robotic technology minimized the degree of invasiveness, hastened postoperative recovery, and improved quality of life, although length of hospital stay was unchanged.

Adult↗