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Marc R Moon

Publications and source records attributed to Marc R Moon.

At least 19 recordsLinked to original sources

Implantable cardioverter-defibrillators improve survival after coronary artery bypass grafting in patients with severely impaired left ventricular function.

OBJECTIVE: Patients with severe left ventricular (LV) dysfunction have a poor long term survival despite complete surgical revascularization. Recent data suggests that the use of Implantable Cardioverter-Defibrillator (ICD) improves survival in patients with severe LV dysfunction. We compared the survival impact of ICD implantation in patients with severe LV dysfunction who underwent CABG. METHODS: Between January 1996 and August 2004, 305 patients with LV ejection fraction (EF) < or = 25% had CABG surgery at our institution. Demographics of patients who had received an ICD (ICD+) in the post -operative period was compared to those without ICD (ICD-). Survival was evaluated by the Kaplan-Meier method. RESULTS: Of the entire group, 35 (11.5%) patients received an ICD with a median of 2 (+/-2) years after CABG. Indication for ICD implantation was clinical evidence of non sustained ventricular tachycardia (NSVT). There were no differences between the 2 groups with respect to age, gender, NYHA classification, number of bypasses, or other co-morbidities. Survival at 1, 3 and 5 years was 88%, 79%, and 67% for the ICD- group compared to 94%, 89% and 83% for the ICD+ group, respectively (figure, p < 0.05). CONCLUSION: Implantation of ICD after CABG confers improved short and long term survival benefit to patients with severe LV dysfunction. Prophylactic ICD implantation in the setting of severe LV dysfunction and CABG surgery should be considered.

Aged↗

Long-term outcomes in valve replacement surgery for infective endocarditis.

BACKGROUND: Infective endocarditis is associated with a high rate of long-term mortality. Patients with a history of intravenous drug use (IVDU) are at increased risk for infective endocarditis. However, few studies have reported results of surgical treatment on this population. We present 19.5 years of experience with surgically treated patients with infective endocarditis. METHODS: A retrospective study of all cardiac surgeries with a diagnosis of infective endocarditis at a single institution from 1986 to 2005 was performed. Logistic stepwise regression with an end point of operative mortality was done. Variables were age, gender, race, history of drug use, previous valve surgery, and previous valve replacement. Perioperative and outcome variables were compared between IVDU and non-IVDU populations. RESULTS: The IVDU population required surgery at a younger age (39 +/- 9 years versus 54 +/- 15 years; p < 0.001). Overall operative mortality was 12% (41/346). The perioperative complication rate was similar for both groups. When adjusted for age, the two groups had similar long-term survival (p = 0.78). Kaplan-Meier estimator showed that survival at 10 and 15 years was 66% and 54% for IVDU and 56% and 42% for non-IVDU (number at risk, 19, 11, and 61, 28, respectively; p = 0.137). Reoperation for recurrent infective endocarditis was necessary in 9 (17%) of 52 of the IVDU group versus 14 (5%) of 270 of the non-IVDU group (p = 0.03). CONCLUSIONS: Patients with a history of IVDU required reoperation for recurrent infective endocarditis at a significantly higher rate than the non-IVDU patients. Long-term survival was similar between the younger IVDU population and the older non-IVDU population. Anticipated life span is one of many factors when considering prosthetic valve choice in this population.

Adult↗

Endovascular repair of thoracic aortic lesions using infrarenal devices: lessons learned and continued applications.

The application of endovascular devices for the treatment of a variety of thoracic aortic lesions has flourished worldwide over the past decade. Until physicians become facile with recently approved thoracic devices and these devices are immediately available even in emergency situations, the use of endovascular abdominal components offers physicians more options in managing thoracic lesions. We evaluated the safety, efficacy, and outcomes of commercially available, infrarenal endovascular graft components for managing lesions of the thoracic aorta. Nineteen patients were treated outside of a clinical trial using commercially available endovascular devices. The indications for treatment included acute traumatic lesions (n = 7), symptomatic ulcers (n = 4), focal aneurysms or pseudoaneurysms (n = 7), and symptomatic type B dissection (n = 1). The endovascular components included Excluder Aortic Cuffs (n = 9), AneuRx Aortic Cuffs (n = 5), Zenith Aortic Cuffs (n = 2), Zenith Aortic Tube Grafts (n = 2), and graft combinations (n = 1). Seventeen patients (89%) underwent successful endovascular treatment of their thoracic lesion. One patient required elective surgical conversion, and a second patient had a dissection that was not completely sealed endovascularly. There was no periprocedural mortality, and the major complication rate was 16% (3/19). Two patients had asymptomatic troponin leaks, and one patient developed an iliac rupture at the device introduction site, hypotension, and paraplegia. At a mean follow-up of 12.3 months, all successfully treated patients continue to have complete exclusion of the treated lesion. Infrarenal endovascular graft components can be very useful in the treatment of selected patients with amenable thoracic lesions until thoracic devices are available in all necessary sizes, readily accessible to treating physicians, and cost-effective.

Adult↗

Prosthesis-patient mismatch after aortic valve replacement: impact of age and body size on late survival.

BACKGROUND: The purpose of this study was to identify patient subgroups in which prosthesis-patient mismatch most influenced late survival. METHODS: Over a 12-year period, 1,400 consecutive patients underwent bioprosthetic (933 patients) or mechanical (467) aortic valve replacement. Prosthesis-patient mismatch was defined as prosthetic effective orifice area/body surface area less than 0.75 cm2/m2 and was present with 11% mechanical and 51% bioprosthetic valves. RESULTS: With bioprosthetic valves, prosthesis-patient mismatch was associated with impaired survival for patients less than 60 years old (10-year: 68% +/- 7% mismatch versus 75% +/- 7% no mismatch, p < 0.02) but not older patients (p = 0.47). Similarly, with mechanical valves, prosthesis-patient mismatch was associated with impaired survival for patients less than 60 years old (10-year: 62% +/- 11% versus 79% +/- 4%, p < 0.005) but not older patients (p = 0.26). For small patients (body surface area less than 1.7 m2), prosthesis-patient mismatch did not impact survival with bioprosthetic (p = 0.32) or mechanical (p = 0.71) valves. For average-size patients (body surface area 1.7 to 2.1 m2), prosthesis-patient mismatch was associated with impaired survival with both bioprosthetic (p < 0.05) and mechanical (p < 0.005) valves. For large patients (body surface area greater than 2.1 m2), prosthesis-patient mismatch was associated with impaired survival with mechanical (p < 0.04) but not bioprosthetic (p = 0.40) valves. CONCLUSIONS: Prosthesis-patient mismatch had a negative impact on survival for young patients, but its impact on older patients was minimal. In addition, although prosthesis-patient mismatch was not important in small patients, prosthesis-patient mismatch negatively impacted survival for average-size patients and for large patients with mechanical valves.

Adult↗

Elective surgery for thoracic aortic aneurysms: late functional status and quality of life.

BACKGROUND: Elective surgical treatment for thoracic aortic aneurysms is unique in that it is often performed on asymptomatic patients. Although it has been found to improve survival, the impact of elective surgery on late functional status and quality of life have yet to be examined. METHODS: Over a 5-year period, 110 asymptomatic patients underwent elective thoracic aortic replacement for ascending, descending, or thoracoabdominal aneurysms. Mean age was 67 +/- 9 years (53 > or = 70 years). Functional status, physical and psychological quality of life (Medical Outcome Study 36-Item Short Form Health Survey, in which 50 represents normalized age-matched US population), and survival (Kaplan-Meier) were assessed. RESULTS: Return to normal activity level was independent of age (p > 0.59) and procedure (p > 0.18). At 35 +/- 20 months, psychological quality of life was similar between surgical groups (p > 0.71), but physical quality of life was lower after thoracoabdominal versus ascending or descending aneurysms (p < 0.02). Age did not impact physical quality of life (40 +/- 13 > or = 70 years versus 42 +/- 11 < 70 years, p > 0.58), but older patients had improved psychological quality of life (52 +/- 9 > or = 70 years versus 47 +/- 8 < 70 years, p > 0.03). Overall survival was 79% +/- 4% at 2 years and 70% +/- 5% at 4 years, but was lower with thoracoabdominal versus ascending or descending aneurysms (p < 0.002). Multivariate analysis identified thoracoabdominal (p < 0.004), advanced age (p < 0.03), chronic renal failure (p < 0.03), and congestive heart failure (p < 0.001) as predictors of late death. CONCLUSIONS: Advanced age did not impair return to normal functional status, and older patients had improved psychological quality of life. Survival and physical quality of life were lowest with thoracoabdominal versus ascending or descending aneurysms. Thus, patients with asymptomatic thoracic aneurysms should not be denied elective replacement based on age alone, as functional recovery was not significantly impaired.

Aged↗

A new era in the surgical treatment of atrial fibrillation: the impact of ablation technology and lesion set on procedural efficacy.

BACKGROUND/OBJECTIVE: While the Cox-Maze procedure remains the gold standard for the surgical treatment of atrial fibrillation (AF), the use of ablation technology has revolutionized the field. To simplify the procedure, our group has replaced most of the incisions with bipolar radiofrequency ablation lines. The purpose of this study was to examine results using bipolar radiofrequency in 130 patients undergoing a full Cox-Maze procedure, a limited Cox-Maze procedure, or pulmonary vein isolation alone. METHODS: A retrospective review was performed of patients who underwent a Cox-Maze procedure (n = 100), utilizing bipolar radiofrequency ablation, a limited Cox-Maze procedure (n = 7), or pulmonary vein isolation alone (n = 23). Follow-up was available on 129 of 130 patients (99%). RESULTS: Pulmonary vein isolation was confirmed by intraoperative pacing in all patients. Cross-clamp time in the lone Cox-Maze procedure patients was 44 +/- 21 minutes, and 104 +/- 42 minutes for the Cox-Maze procedure with a concomitant procedure, which was shortened considerably from our traditional cut-and-sew Cox-Maze procedure times (P < 0.05). There were 4 postoperative deaths in the Cox-Maze procedure group and 1 in the pulmonary vein isolation group. The mean follow-up was 13 +/- 10, 23 +/- 15, and 9 +/- 10 months for the Cox-Maze IV, the pulmonary vein isolation, and the limited Cox-Maze procedure groups, respectively. At last follow-up, freedom from AF was 90% (85 of 94), 86% (6 of 7), and 59% (10 of 17) in the in the Cox-Maze procedure group, limited Cox-Maze procedure group, and pulmonary vein isolation alone group, respectively. CONCLUSIONS: The use of bipolar radiofrequency ablation to replace Cox-Maze incisions was safe and effective at controlling AF. Pulmonary vein isolation alone was much less effective, and should be used cautiously in this population.

Atrial Fibrillation↗

Management of arterial injuries caused by laser extraction of indwelling venous pacemaker and defibrillator leads.

The use of laser technology for the removal of pacemaker and defibrillator leads has decreased the lead extraction time and improved the success rate for complete lead removal when compared to traditional techniques. However, this extraction method may be associated with significant complications. This report documents two cases of iatrogenic arteriovenous fistula created by laser lead extraction. Endovascular repair of these fistulas provides an effective and less invasive alternative to open repair.

Aged↗

Laser assistance for extraction of chronically implanted endocardial leads: infectious versus noninfectious indications.

BACKGROUND: Powered sheaths, including Excimer laser sheaths, were introduced for the removal of transvenous pacing and defibrillator leads. The purpose of this study was to develop an algorithm to better predict which patients are likely to benefit from these devices. METHODS: We reviewed 283 consecutive patients in whom a total of 500 leads (302 pacing and 198 defibrillator leads) were extracted over a 5-year period at our operative facilities. Laser assist was utilized whenever moderate traction failed. RESULTS: In 128 patients, 203 leads were removed for noninfectious indication. In 155 patients, 297 leads for infectious indications, including sepsis 22% (111), pocket infection 23% (115), and erosion 14% (71). Laser assistance was required for 6%+/- 5% (+/- 95% confidence interval) of septic leads, 51%+/- 7% of leads associated with erosion or pocket infection and 60%+/- 7% of noninfected leads (P = 0.001). Laser assistance was necessary more often for leads implanted >12 months (53%+/- 5%) than 12 months or less (6%+/- 5%) (P = 0.001) and for ventricular (52%+/- 6%) compared to atrial (35%+/- 7%) leads (P = 0.001). CONCLUSIONS: Chronically implanted leads (>12 months), especially noninfected leads and leads associated with erosion or pocket infection, should be referred for extraction with powered sheaths to ensure successful removal. However, leads that are associated with systemic sepsis can generally be removed without powered sheaths.

Adolescent↗

Right atrial and ventricular adaptation to chronic right ventricular pressure overload.

BACKGROUND: Increased mortality in patients with chronic pulmonary hypertension has been associated with elevated right atrial (RA) pressure. However, little is known about the effects of chronic right ventricular (RV) pressure overload on RA and RV dynamics or the adaptive response of the right atrium to maintain RV filling. METHODS AND RESULTS: In 7 dogs, RA and RV pressure and volume (conductance catheter) were recorded at baseline and after 3 months of progressive pulmonary artery banding. RA and RV elastance (contractility) and diastolic stiffness were calculated, and RA reservoir and conduit function were quantified as RA inflow with the tricuspid valve closed versus open, respectively. With chronic pulmonary artery banding, systolic RV pressure increased from 34+/-7 to 70+/-17 mm Hg (P<0.001), but cardiac output did not change (P>0.78). RV elastance and stiffness both increased (P<0.05), suggesting preserved systolic function but impaired diastolic function. In response, RA contractility improved (elastance increased from 0.28+/-0.12 to 0.44+/-0.13 mm Hg/mL; P<0.04), and the atrium became more distensible, as evidenced by increased reservoir function (49+/-14% versus 72+/-8%) and decreased conduit function (51+/-14% versus 28+/-8%; P<0.002). CONCLUSIONS: With chronic RV pressure overload, RV systolic function was preserved, but diastolic function was impaired. To compensate, RA contractility increased, and the atrium became more distensible to maintain filling of the stiffened ventricle. This compensatory response of the right atrium likely plays an important role in preventing clinical failure in chronic pulmonary hypertension.

Adaptation, Physiological↗

Impact of complete revascularization on long-term survival after coronary artery bypass grafting in octogenarians.

BACKGROUND: Complete revascularization is important in young patients undergoing coronary artery bypass grafting, but this principle remains less absolute in elderly patients. The purpose of this study was to determine how complete revascularization influenced long-term survival after coronary artery bypass grafting in octogenarians. METHODS: From 1986 to 2003, 500 consecutive patients 80 to 94 years of age underwent coronary artery bypass grafting. Complete revascularization was defined as placement of at least one graft to each of the three major vascular regions that included a 50% diameter lesion. Revascularization was complete in 400 (80%) patients and incomplete in 100 (20%) patients. Mean (+/- standard deviation) follow-up was 51 +/- 41 months and was 99% complete (2,102 total patient-years). RESULTS: Operative mortality was 8% +/- 2% (+/-95% confidence interval) and was statistically lower with complete (7% +/- 3%) versus incomplete (13% +/- 7%) revascularization (p < 0.05). Of 459 operative survivors, there were 261 late deaths. Multivariate regression analysis identified six independent predictors of late death: earlier operative year, male sex, peripheral or cerebrovascular disease, congestive heart failure, and incomplete revascularization (p < 0.03 for all). Excluding operative deaths, mean survival (Kaplan-Meier) was 82 months with complete revascularization compared with 65 months with incomplete revascularization (p < 0.008). Survival was 62% +/- 3% with complete versus 45% +/- 6% with incomplete revascularization at 5 years and 39% +/- 3% with complete versus 25% +/- 6% with incomplete revascularization at 8 years (p < 0.008). CONCLUSIONS: In octogenarians undergoing coronary artery bypass grafting, complete revascularization correlated with improved long-term survival, increasing mean survival by almost 25% compared with incomplete revascularization.

Age Factors↗

Radial artery grafts in women: utilization and results.

BACKGROUND: Despite a known survival benefit with the use of the left internal mammary artery, it is used less frequently in women when compared with men. This study evaluated the hypotheses that the radial artery graft is used less frequently in women compared with men, that the radial artery is smaller in women compared with men, and that the use of the radial artery influences operative mortality and long-term survival in women. METHODS: The use of a radial artery graft was evaluated in 2,633 patients who underwent isolated coronary artery bypass. Radial artery size and flow were compared in 207 patients who had intraoperative radial artery diameter and flow measurements. Propensity scoring was utilized to compare short- and long-term outcomes in a matched cohort of 588 women. RESULTS: Of 862 women (33%) who had isolated coronary artery bypass grafting, only 301 (35%) received a radial artery graft versus 44% of men (786 of 1,771, p < 0.001). Radial artery size and flow were significantly less in women. Operative mortality was not different between women with a radial artery graft and women without; however, 5-year survival was significantly better in women with a radial artery graft than in those without. CONCLUSIONS: Women received fewer radial artery grafts than men. Radial artery size and flow were significantly less in women than in men. Use of a radial artery graft did not influence operative mortality among women. However, 5-year survival among women who received a radial artery graft was significantly better than among women who did not.

Aged↗

The bicuspid aortic valve.

The bicuspid aortic valve affects 1 to 2% of the population and may be complicated by aortic stenosis or aortic insufficiency and infective endocarditis. The bicuspid aortic valve is associated with abnormalities of the aortic wall such as coarctation of the aorta, aortic dissection, and aortic aneurysm. Most patients with a bicuspid aortic valve will develop some complication during life. Individuals with a bicuspid valve may be unaware of its presence and are at risk for unsuspected complications. Aortic wall abnormalities associated with bicuspid aortic valve are due to cystic medial necrosis. This process is associated with increased metalloproteinase activity and apoptosis of vascular smooth muscle cells. The clinical correlates of aortopathy in the bicuspid aortic valve include significant enlargement of the ascending aorta with aneurysm formation and dissection. This process continues after valve replacement. The person with bicuspid aortic valve requires continuous surveillance to treat associated lesions and prevent complications.

Aortic Valve↗

Preoperative use of enoxaparin increases the risk of postoperative bleeding and re-exploration in cardiac surgery patients.

OBJECTIVE: The purpose of this study was to investigate if the preoperative use of new platelet inhibitors and low-molecular-weight heparins may contribute to bleeding after cardiac surgery. DESIGN: Retrospective data review. SETTING: University teaching hospital. PARTICIPANTS: One hundred eleven patients divided in 5 groups. INTERVENTIONS: Patients were grouped according to preoperative antithrombotic regimen: group 1, control, no agents (n=55); group 2, clopidogrel (n=9); group 3, enoxaparin (n=17); group 4, any GP IIb/IIIa inhibitor (n=14); and group 5, any drug combination (n=15). Data included cumulative mediastinal chest tube drainage, allogeneic blood transfusions, total blood donor exposures, and re-exploration. MEASUREMENTS AND MAIN RESULTS: Use of any drug (groups 2-5) resulted in greater total blood transfusions and donor exposure (p=0.0003) than control, especially red cells (p=0.002) and platelets (p=0.006). A greater percentage of patients on enoxaparin required mediastinal re-exploration for nonsurgical bleeding versus control (3/17 v 0/55, p=0.001). The use of enoxaparin was associated with significantly higher chest tube output after the first 24 hours postoperatively (p=0.048). CONCLUSION: Newer antithrombotic agents were associated with greater transfusion rates and total donor exposures. Enoxaparin use was associated with greater overall blood loss and with higher incidence of mediastinal re-exploration. The relative risk-benefit ratio of reduced periprocedure morbidity versus increased bleeding complications has yet to be determined.

Analysis of Variance↗

Strategies for temporary mechanical support: contemporary experience with pulsatile and non-pulsatile support systems.

Despite advances in mechanical circulatory support, cardiogenic shock continues to have a high mortality. We reviewed our experience with pulsatile versus non-pulsatile temporary mechanical support at our institution to determine optimal strategy for survival. From January 2001 to December 2003, mechanical support for cardiogenic shock was instituted in 38 patients. Non-pulsatile devices (NP group) were used in 22 patients and pulsatile devices (P group) in 16 patients. Indications for the NP group were post-cardiotomy shock (PCS) in 17, myocardial infarction in 2, and isolated post-cardiotomy right ventricular failure in 3 patients. In the P group, 9 had the device placed for PCS, 3 for viral myocarditis, 1 after myocardial infarction, and 3 for right ventricular (RV) failure. Overall, bleeding, limb ischemia, and multi-system organ failure were higher in NP group with 5 weaned and 3 surviving to discharge (14%). In the P group, survivors included 7 weaned and 3 transplanted patients (63%). With the exception of isolated RV failure, we obtained a dismal survival result with ECMO/centrifugal circuits for treatment of cardiogenic shock. For refractory pump failure, improved survival was achieved by using intermediate-term pulsatile devices with early transition to a chronic device and/or heart transplantation.

Female↗

Reservoir and conduit function of right atrium: impact on right ventricular filling and cardiac output.

The purpose of this study was to investigate the relationship between right atrial (RA) reservoir and conduit function and to determine how hemodynamic changes influence this relationship and its impact on cardiac output. In 11 open-chest sheep, RA reservoir and conduit function were quantified as RA inflow with the tricuspid valve closed versus open, respectively. Conduit function was separated into early (before A wave) and late (after A wave) components. The effects of inotropic stimulation, partial pulmonary artery occlusion, and pericardiotomy were tested. At baseline with the pericardium intact, reservoir function accounted for 0.56 (SD 0.13) of RA inflow, early conduit for 0.29 (SD 0.07), and late conduit (during RA contraction) for 0.16 (SD 0.11). Inotropic stimulation decreased conduit function and increased reservoir function, but these effects did not reach statistical significance. With partial pulmonary artery occlusion, early conduit function fell to 0.20 (SD 0.11) (P < 0.04), and the conduit-to-reservoir ratio decreased by 41% (P < 0.03). Similarly, after pericardiotomy, early conduit function fell to 0.14 (SD 0.09) (P < 0.004), reservoir function increased to 0.72 (SD 0.08) (P < 0.04), and, consequently, the early conduit-to-reservoir ratio decreased by 63% (P < 0.006). Cardiac output was inversely related to the conduit-to-reservoir ratio (r = 0.39, P < 0.001). This study demonstrated that the right atrium adjusts its ability to act more as a reservoir than a conduit in a dynamic manner. The RA conduit-to-reservoir ratio was directly related to the right ventricular pressure-RA pressure gradient at the time of maximum RA volume, with increased ventricular pressures favoring conduit function, but it was inversely related to cardiac output, with an increase in the reservoir contribution favoring improved cardiac output.

Acute Disease↗

Long-term neurologic hand complications after radial artery harvesting using conventional cold and harmonic scalpel techniques.

BACKGROUND: The purpose of this study was to determine the incidence of neurologic hand complications after radial artery harvesting and to compare the harmonic scalpel versus conventional cold scalpel technique. METHODS: From 1995 to 2000, 786 radial arteries were harvested from 782 patients for coronary artery bypass grafting. From 1995 to 1997, the conventional cold scalpel technique was used (422 patients), and from 1998 to 2000, the harmonic scalpel was used (360 patients). Mean follow-up was 4.2 +/- 2.1 years and was 90% complete. Symptoms included thumb weakness or numbness, tingling, or pain in the hand. RESULTS: The incidence of neurologic hand complications was similar with both techniques (11.2% +/- 3.5% cold, 11.0% +/- 3.6% harmonic, p > 0.95), and in 19% (13 of 67 with symptoms) there was complete resolution within 1 year. Symptoms persisted long-term in 9.0% +/- 3.2% cold scalpel and 9.0% +/- 3.3% harmonic scalpel patients (p > 0.81), but were considered a "constant and significant source of discomfort" in only 0.6% +/- 0.9% cold scalpel and 1.4% +/- 1.3% harmonic scalpel patients (p > 0.41). CONCLUSIONS: The incidence of adverse neurologic outcomes causing significant long-term discomfort in the hand was low using either the cold scalpel or harmonic scalpel technique. However, a significant number of patients had neurologic hand symptoms in both groups, and this should be included when discussing operative risks with the patient.

Aged↗

Repair of ischemic mitral regurgitation does not increase mortality or improve long-term survival in patients undergoing coronary artery revascularization: a propensity analysis.

BACKGROUND: The purpose of this study was to compare operative mortality and midterm outcome of patients with ischemic mitral regurgitation (MR) undergoing either coronary artery bypass grafting (CABG) alone or CABG with mitral valve (MV) repair. METHODS: From 1996 to 2001, 51 consecutive patients underwent CABG with MV repair for ischemic MR. All patients in this group were matched to similar patients with ischemic MR undergoing CABG alone during the same 6-year period using propensity analysis (considering 24 covariates, including severity of MR and New York Heart Association [NYHA] class). RESULTS: Propensity score matching yielded 51 closely matched control patients. Preoperative MR severity was 3+ or 4+ in 94% of CABG with MV repair and 96% of CABG-alone patients, and 86% of patients in each group were NYHA class III or IV. Operative mortality was 3.9% +/- 2.8% in both groups. Survival was also similar between CABG with MV repair and CABG alone at 1 year (84% +/- 5% versus 82% +/- 5%) and 3 years (70% +/- 7% versus 71% +/- 7% (p = 0.43). Among survivors, NYHA class improved at follow-up (50 +/- 20 months) from 3.4 +/- 0.7 to 1.7 +/- 1.0 for CABG with MV repair (p < 0.001) and from 3.4 +/- 0.7 to 1.8 +/- 1.0 for CABG alone (p < 0.001). CONCLUSIONS: Operative mortality, midterm survival, and late functional class were similar between two well-matched groups of patients undergoing CABG for ischemic MR, differing only in the addition of MV repair. Whereas MV repair can be added safely to CABG in this group of high-risk patients without increasing mortality, its impact on late survival and functional class may be limited.

Aged↗

A prospective multicenter trial of bipolar radiofrequency ablation for atrial fibrillation: early results.

BACKGROUND: The Cox-Maze III remains the gold standard for the surgical treatment of atrial fibrillation. However, the "cut-and-sew" technique is time consuming and technically challenging. The pulmonary veins are the source of ectopy in the majority of patients with atrial fibrillation. The safety and efficacy of bipolar radiofrequency to electrically isolate the pulmonary veins was evaluated in a prospective multi-center trial. METHODS: Beginning in January 2002, 30 patients at three medical centers underwent pulmonary vein isolation using bipolar radiofrequency and were followed for 6 months. Twenty-four of the patients also underwent a modified Cox-Maze III. Electrical isolation of the pulmonary veins was confirmed with intraoperative pacing. Pulmonary vein patency was assessed by magnetic resonance imaging or three-dimensional computed tomography in 15 patients at 1 month. RESULTS: Mean age was 60.9 +/- 11.7 years. Nineteen patients had paroxysmal atrial fibrillation. All pulmonary veins were isolated in every patient. The left pulmonary veins underwent 3.0 +/- 1.4 applications for a total of 26.4 +/- 10.5 seconds. The right pulmonary veins underwent 2.8 +/- 1.1 applications for a total of 26.3 +/- 12.6 seconds. There was no operative mortality. At 1 month, imaging revealed no evidence of pulmonary vein stenosis. At 6 months, 96% of patients were in normal sinus rhythm. CONCLUSIONS: The use of bipolar radiofrequency for electrical isolation of pulmonary veins and to replace other Cox-Maze III incisions is safe and effective at controlling atrial fibrillation. This emerging technology may shorten and simplify the surgical management of atrial fibrillation.

Aged↗