Persistent reduction of mitral regurgitation by implantation of a transannular mitral bridge: durability and effectiveness of the repair at 2 years-results of a prospective trial†.

OBJECTIVES: Ring annuloplasty reduces the septal-lateral diameter (SLD) indirectly by circumferential annular cinching and frequently results in the recurrence of mitral regurgitation (MR) in patients with functional MR (FMR). Our goal was to report the results from the trial and the 2-year post-trial surveillance data. We evaluated whether direct reduction of the SLD with a transannular mitral bridge could achieve significant and durable MR reduction in patients with FMR. METHODS: In a prospective trial, 34 consecutive patients with FMR had a mitral bridge implanted surgically. Primary end points were MR ≤1+ at 1, 3 and 6 months postimplant and freedom from subsequent surgical mitral valve repair or replacement. RESULTS: Thirty-two of 34 (94.1%) patients met the primary end points with MR ≤1+ at 6 months. At 2 years, there were no strokes or device-related adverse events. At 2 years, MR was reduced from 3.32 ± 0.47 to 0.50 ± 0.83 (P ≤ 0.001) with ≤1+ MR in 33/34 patients, including 4 reinterventions for periprosthetic recurrent MR ≥3 without mitral bridge explants or conventional mitral repair or replacement. At 2 years, the mean mitral gradient was 2.15 ± 0.82 mmHg; the mitral annular SLD decreased from 40.4 ± 2.91 mm to 28.9 ± 1.55 mm (P ≤ 0.001). The left ventricular ejection fraction increased (57.9 ± 10.4-62.4 ± 9.7%; P ≤ 0.001). The New York Heart Association functional class improved (2.19 ± 0.76-1.41 ± 0.61; P ≤ 0.001). CONCLUSIONS: The single-centre trial data indicate that direct reduction in the SLD with a mitral bridge is feasible, safe and efficacious in patients with FMR. Validation in a larger population of patients and comparison to conventional annuloplasty ring are necessary. CLINICAL TRIAL REGISTRATION NUMBER: NCT03511716.

Increasing surgical experience with off-pump coronary surgery does not mitigate the morbidity of emergency conversion to cardiopulmonary bypass.

OBJECTIVE: Emergency conversion during off-pump coronary artery bypass (OPCAB) confers significant morbidity. We sought to determine whether the outcomes in these patients have changed as our experience with off-pump techniques has increased. METHODS: Between January 1999 and December 2010, 4763 patients underwent coronary artery surgery. An off-pump strategy was attempted in 4415 cases (92.7%). The results of the most recent 50 patients who required emergency conversion were compared with the preceding 50 conversions and with patients who underwent either OPCAB (n = 2737) or on-pump coronary surgery (coronary artery bypass grafting) (n = 268) during the same time frame. RESULTS: The emergency conversion rate was 2.27% (n = 100), being 2.97% for the first 50 cases and 1.77% for the subsequent 50 patients. The two sequential groups of emergency conversions had similar indications and timing of conversion and comparable outcomes. When compared with patients who underwent OPCAB, the more recent 50 conversions had higher mortality (P = 0.002) and more frequent sternal wound infection (P = 0.036), hemorrhage requiring reoperation (P = 0.003), respiratory failure (P < 0.0001), and all-cause sepsis (P = 0.001). Compared with the on-pump group, the more recent conversions had higher mortality (P = 0.055) and a greater rate of postoperative sepsis (P = 0.002). CONCLUSIONS: The incidence of emergency conversion during OPCAB has decreased with increasing surgical experience; however, the morbidity in these patients remains essentially unchanged. The outcomes in these patients remain worse than those in nonconverted patients. Safer bailout strategies during OPCAB are still warranted.

Hybrid minimally invasive extraction of atrial clot avoids redo sternotomy in Jehovah's Witness.

We report the novel use of the AngioVac device in a percutaneous hybrid approach to remove a large right atrial clot as an effective and potentially lifesaving alternative to a very high-risk redo-sternotomy in a Jehovah's Witness patient.

Does body mass index affect outcomes in robotic-assisted coronary artery bypass procedures?

OBJECTIVE: Obese patients pose unique technical challenges for minimal-access cardiac surgery. We sought to examine the effect of body mass index on short-term outcomes in robotic-assisted coronary surgery. METHODS: From January 2010 to November 2011, a total of 110 consecutive patients underwent robotic-assisted coronary surgery at our institution. All patients had robotic-assisted mobilization of the left internal mammary artery. Some patients then underwent direct coronary anastomosis to the left anterior descending coronary artery via a left mini thoracotomy, whereas others had a complete robotic endoscopic procedure within the closed chest. The short-term outcomes of obese patients (n = 39), defined as body mass index greater than 30 kg/m, were compared with those of nonobese patients (n = 71). RESULTS: Mean left internal mammary artery harvest time was longer in obese patients than in nonobese patients (51.03 vs 39.94 minutes; P = 0.007), as was overall operative time (218.15 vs 186.72 minutes; P = 0.034). There were no significant differences in mortality or major morbidity between obese and nonobese patients. CONCLUSIONS: Obesity does not adversely affect short-term outcomes in robotic-assisted coronary surgery, although operative times are somewhat longer for these patients. Robotic-assisted coronary techniques can be safely pursued in obese patients.

A step toward nonrobotic total endoscopic coronary bypass grafting: 40 coronary anastomoses in a biomechanical beating heart model.

OBJECTIVE: Nonrobotic total endoscopic coronary bypass grafting is commonly considered as technically too difficult. After endoscopic practicing in a simple box model, we questioned this statement in a more sophisticated training model. METHODS: In a handmade chest model containing a mechanically actuated porcine heart, anastomoses between homologous vein and shunted anterior coronary artery were performed using Prolene 7-0 sutures or U-clips in 20 anastomoses each. Commercially available endoscopic instruments and exclusive two-dimensional endoscopic vision were used. As quality control, the procedures were recorded, flow was measured, indocyanine green dye angiograms were performed, vinylpolysiloxane endocasts were produced, and finally the anastomoses were assessed from the endothelial side. Three-dimensional computed tomographic reconstruction was explored for cast measuring. RESULTS: All anastomoses were completed successfully in a time of 51 ± 14 minutes (Prolene) and 48 ± 10 minutes (U-clips). Despite suboptimal equipment, a reproducible sequence of the procedure was established and documented. Improving surgical performance was reflected in a reduction in anastomotic leakage and time requirement. The quality assessment protocol showed a learning curve and problems itself, which are briefly discussed. CONCLUSIONS: A beating heart model is an adamant requirement of training for the technically demanding procedure of nonrobotic total endoscopic coronary bypass grafting. Refinement of the model and quality assessment as well as expansion of training to other regions of the heart should prepare for a cost-effective, broad-based clinical application of nonrobotic endoscopic techniques in coronary surgery. Available high-definition three-dimensional vision systems and the development of appropriate (articulating) instruments will make the procedure safer and quicker and will cut the learning curve.

Does dual antiplatelet therapy affect blood loss and transfusion requirements in robotic-assisted coronary artery surgery?

OBJECTIVE: Patients who present for coronary surgery often receive preoperative dual antiplatelet therapy with aspirin and a thienopyridine derivative (clopidogrel or prasugrel), especially after a recent acute coronary syndrome. Studies have shown that patients on aspirin and clopidogrel are at increased risk for perioperative bleeding and related events. We sought to examine the impact of dual antiplatelet therapy on bleeding and transfusion requirements in patients undergoing robotic-assisted minimally invasive coronary artery bypass grafting. METHODS: From January 2010 to November 2011, a total of 110 patients underwent robotic-assisted off-pump coronary surgery at our institution. All patients underwent robotic-assisted harvest of the left internal mammary artery from the chest wall. Some patients then underwent direct coronary anastomosis to the left anterior descending coronary artery via a left minithoracotomy, whereas others had a complete robotic endoscopic procedure within the closed chest. The patients were divided into two groups for outcome analysis on the basis of preoperative antiplatelet therapy: group 1 (either aspirin alone or no antiplatelet agents at all; n = 53) and group 2 (aspirin plus clopidogrel or prasugrel; n = 57). RESULTS: Perioperative chest tube drainage was not significantly different between the patient groups, irrespective of the preoperative antiplatelet agents used. Transfusion requirements and other morbidities were also similar in both groups of patients. CONCLUSIONS: Preoperative dual antiplatelet therapy does not result in significantly increased bleeding or perioperative transfusion requirements. If clinically indicated, it is reasonable to continue preoperative combination antiplatelet therapy in patients undergoing robotic-assisted coronary surgery.

Outcomes of coronary artery bypass grafting and reduction annuloplasty for functional ischemic mitral regurgitation: a prospective multicenter study (Randomized Evaluation of a Surgical Treatment for Off-Pump Repair of the Mitral Valve).

OBJECTIVE: Functional ischemic mitral regurgitation is a complication of ventricular remodeling; standard therapy is reduction annuloplasty and coronary artery bypass grafting. Unfortunately, outcomes are retrospective and contradictory. We report a multicenter study that documents the outcomes of reduction annuloplasty for functional ischemic mitral regurgitation. METHODS: Twenty-one centers randomized 75 patients to the coronary artery bypass grafting + reduction annuloplasty subgroup that was the control arm of the Randomized Evaluation of a Surgical Treatment for Off-pump Repair of the Mitral Valve trial. Entry criteria included patients requiring revascularization, patients with severe or symptomatic moderate functional ischemic mitral regurgitation, an ejection fraction 25% or greater, a left ventricular end-diastolic dimension 7.0 cm or less, and more than 30 days since acute myocardial infarction. All echocardiograms were independently scored by a core laboratory. Reduction annuloplasty was achieved by device annuloplasty. Two patients underwent immediate intraoperative conversion to a valve replacement because reduction annuloplasty was unable to correct mitral regurgitation; as-treated results are presented. RESULTS: Thirty-day mortality was 4.1% (3/73). Patients received an average of 2.8 bypass grafts. Mean follow-up was 24.6 months. Mitral regurgitation was reduced from 2.6 ± 0.8 preoperatively to 0.3 ± 0.6 at 2 years. Freedom from death or valve reoperation was 78% ± 5% at 2 years. There was significant improvement in ejection fraction and New York Heart Association class with reduction of left ventricular end-diastolic dimension. Cox regression analyses suggested that increasing age (P = .001; hazard ratio, 1.16 per year; 95% confidence interval, 1.06-1.26) and renal disease (P = .018; hazard ratio, 3.48; 95% confidence interval, 1.25-9.72) were associated with decreased survival. CONCLUSIONS: Coronary artery bypass grafting + reduction annuloplasty for functional ischemic mitral regurgitation predictably reduces mitral regurgitation and relieves symptoms. This treatment of moderate to severe mitral regurgitation is associated with improved indices of ventricular function, improved New York Heart Association class, and excellent freedom from recurrent mitral insufficiency. Although long-term prognosis remains guarded, this multicenter study delineates the intermediate-term benefits of such an approach.

Minimally invasive direct coronary artery bypass as a primary strategy for reoperative myocardial revascularization.

OBJECTIVE: : Conventional reoperative coronary artery bypass grafting is associated with risk of sternal re-entry, injury to patent grafts, and embolization from diseased grafts. Sternal sparing minimally invasive direct coronary artery bypass (MIDCAB) avoids such risks in cases where it is technically feasible. We sought to examine in-hospital outcomes of reoperative MIDCAB surgery. METHODS: : We recorded prospective standardized data from the New York Cardiac Surgical Reporting System database of 369 reoperative MIDCAB cases from 1996 to 2006 and compared with 822 primary MIDCAB patients in the same time period. We compared the preoperative risk profile and postoperative in-hospital outcomes and length of stay for both groups. RESULTS: : There was a significantly higher risk profile typical of the reoperative patient population (P < 0.001 for stroke, peripheral/cerebrovascular disease, extensive aortic calcification, renal failure, and left ventricular ejection fraction <40%) compared with the primary MIDCAB group. Despite this fact, there was no difference in the in-hospital outcomes and length of hospital stay between the two groups. CONCLUSIONS: : Reoperative MIDCAB provides targeted coronary revascularization and avoids hazards of sternal re-entry, graft injury and manipulation, and deleterious effects of cardiopulmonary bypass. This hastens recovery and provides excellent early outcomes equivalent to primary MIDCAB procedures.

Off-pump Coronary Bypass Surgery in Patients With Low Ejection Fraction: Is There a Long-Term Survival Advantage?

OBJECTIVE: : Long-term survival after off-pump surgery in patients with low ejection fraction was investigated. METHODS: : Three hundred forty-six patients with ejection fraction 30% or less with isolated off-pump coronary artery bypass surgery (OPCAB) were compared with a propensity matched historical group operated on-pump (ONCAB) and with data from literature after percutaneous coronary intervention and OPCAB surgery. RESULTS: : The lower invasiveness of OPCAB contributed to a significantly better 30-day survival, shorter postoperative length of stay, and fewer in-hospital complications. Incomplete revascularization of the posterior and lateral territories of the heart correlated with higher 1-year mortality. The probability of survival for 8 years after OPCAB was 50.1% (n = 76) versus 49.7% (n = 82) for ONCAB without comparable data from literature for OPCAB or percutaneous coronary intervention in these high-risk patients. CONCLUSIONS: : OPCAB surgery in patients with low ejection fraction is a viable alternative but so far without demonstrable long-term survival advantage to ONCAB.

Long-Term Survival After Minimal Invasive Direct Coronary Artery Bypass (MIDCAB) Surgery in Patients With Low Ejection Fraction.

OBJECTIVE: : The long-term survival after minimal invasive direct coronary artery bypass (MIDCAB) surgery to any coronary territory in patients with ejection fraction of ≤30% was investigated for the first time in literature. METHODS: : Seventy-three patients with primary MIDCAB and 89 patients with reoperative MIDCAB were studied including preoperative risk factors, operative details, early postoperative complications, and survival up to 10 years postoperatively. RESULTS: : Despite the high-risk profile of the patients, the MIDCAB approach for targeted revascularization resulted in excellent short-term results. Ventricular arrhythmia contributed to four of six early deaths. Survival at 5 years postoperatively was 62.5% for primary MIDCAB and 43.2% for reoperative MIDCAB and at 10 years was 36.9% and 29.5%, respectively. Functionally complete vascularization correlates with significantly better long-term survival particularly in primary MIDCAB procedures. CONCLUSIONS: : MIDCAB is a valuable option for targeted revascularization in high-risk patients with low ejection fraction and reoperation.

Non-typhoid Salmonellae and prosthetic valve endocarditis: more than a rare coincidence? A review of the literature.

Non-typhoid Salmonellae (NTS) commonly cause gastroenteritis but are rarely found pathogens in prosthetic heart valve endocarditis. The details of two patients from the authors' institution and 15 published cases are reviewed in terms of their risk factors, clinical findings and outcomes. Only two of eight patients with paravalvular leakage or abscess--the most serious local complications--survived, both with surgery. It appears that NTS bacteremia in patients with prosthetic valves and concomitant risk factors should be treated early with high-dose antimicrobials for up to six weeks in order to minimize the risk of endocarditis.

Less invasive intracardiac surgery performed without aortic clamping.

BACKGROUND: Aortic clamping and cardioplegia delivery add complexity to performing intracardiac procedures through a right minithoracotomy. Recent publications have shown excellent patient outcomes after mitral valve (MV) procedures undertaken through thoracotomy on the fibrillating heart. We reviewed our experience with this approach. METHODS: From March 2000 to September 2006, 100 patients underwent MV repair (n = 42), MV annuloplasty (n = 28), MV replacement (n = 18), atrial septal defect closure (n = 10), tricuspid valve repair (n = 1), and left atrial myxoma excision (n = 1). A modified maze procedure (n = 4) or left minimally invasive direct coronary bypass grafting (MIDCABG) (n = 2) was combined in six cases. The mean age was 57 +/- 11 years (range, 22 to 89); 27 patients were in New York Heart Association (NYHA) class III or IV; 24 cases were first or second time reoperations; 20 patients had a left ventricular ejection fraction of less than 0.3. All the operations were carried out on the fibrillating heart without cross-clamping the aorta through a right minithoracotomy using peripheral cannulation. RESULTS: Mean fibrillation time was 73 +/- 31 minutes (range, 10 to 198 minutes). There was no conversion to sternotomy. Postoperative inotropic support was needed in 20 cases. One patient who underwent a third time reoperation died within 30 days of mesenteric ischemia (hospital mortality = 1%). Complications were the following: four reoperations for bleeding (4%); two strokes (2%). Postoperative median hospital length of stay was five days (range, 2 to 58 days). None of the patients has required MV reoperation after hospital discharge. Follow-up was complete. All survivors were in NYHA class I or II. CONCLUSIONS: Ventricular fibrillation simplifies less invasive intracardiac procedures and carries lower complication rates and perioperative mortality compared with conventional surgery.

Minimally invasive coronary artery bypass grafting.

Limited access, off-pump coronary artery bypass grafting for revascularization of all the various coronary arteries is an acceptable alternative to standard on-pump coronary bypass grafting through sternotomy. A variety of small, targeted incisions are used to approach various coronary locations. Technical advances in conduit harvesting, stabilization, cardiac positioning devices, and anastomotic connectors have made these procedures more standardized and replicable. This has resulted in reduced morbidity as a consequence of less invasive approaches. These efforts have paved the way for the ultimate goal of same day surgical coronary revascularization.

Robotic assisted multivessel minimally invasive direct coronary artery bypass with port-access stabilization and cardiac positioning: paving the way for outpatient coronary surgery?

BACKGROUND: Minimimal access multivessel coronary artery bypass grafting with same day hospital discharge remains the ultimate goal. We evaluated the feasibility for achieving multivessel coronary bypass through minimal access. METHODS: From January to July 2003, 30 patients under went off-pump minimally invasive multivessel coronary bypass. Internal mammary arteries were harvested with robotic telemanipulation with three ports. A 2-inch to 3-inch incision with soft tissue retractor was used to perform coronary anastomosis. Robotic ports were used to introduce stabilization and cardiac positioning devices. Endoscopic harvesting of radial artery was done when necessary. RESULTS: Twenty-three patients (77%) had anterior throracotomy approach and 7 (23%) had transabdominal approach. Average number of bypass grafts was 2.6 (range 2-4). There was no mortality in hospital or on 30-day follow-up. Twenty-nine patients (97%) were extubated on the operating table. Two patients required reoperation for bleeding and 1 of those patients needed conversion to sternotomy for additional bypass grafting. Within 24 hours of surgery 50% of patients (n = 15) were discharged, 10% (n = 3) were discharged in 24 to 36 hours, 17% (n = 5) were discharged in 36 to 48 hours, 17% (n = 5) were discharged in 48 to 72 hours, and 2 patients stayed more than 3 days in the hospital. Two patients needed readmission to hospital within 30 days; 1 for pleural effusion and 1 for wound infection. CONCLUSIONS: Robotic harvesting of internal mammary arteries and port access stabilization and cardiac positioning allows multivessel coronary bypass to be performed through a small incision. Currently, the majority of the patients can be safely discharged within 36 hours of operation.

Emergency conversion to cardiopulmonary bypass during attempted off-pump revascularization results in increased morbidity and mortality.

OBJECTIVE: We sought to evaluate outcomes and predictors of emergency conversion to cardiopulmonary bypass during attempted off-pump coronary bypass surgery. METHODS: From January 1999 through July 2002, 1678 consecutive isolated coronary artery bypass operations were performed at Lenox Hill Hospital, with the intention to treat all patients with off-pump coronary bypass surgery. Fifty (2.97%) patients required urgent conversion to cardiopulmonary bypass. All the preoperative, intraoperative, and postoperative variables were collected and analyzed in accordance with the New York State Cardiac Surgery Reporting System. Multivariate regression analysis was performed to determine predictors for conversion. RESULTS: In-hospital mortality and major morbidity were significantly lower in the nonconverted group compared with the converted patients (mortality: 1.47% [n = 24] vs 12% [n = 6], P = .001; stroke: 1.1% [n = 18] vs 6% [n = 3], P = .02; renal failure: 1.23% [n = 20] vs 6% [n = 3], P = .02; deep sternal wound infection: 1.54% [n = 25] vs 8% [n = 4], P = .009; respiratory failure: 3.75% [n = 61] vs 28% [n = 14], P < .0001; nonconverted vs converted patients, respectively). The annual incidence of conversion decreased during the study period. There was a significant reduction in the incidence of conversion after routine use of a cardiac positioning device to performing lateral and inferior wall grafts (4.2% [n = 27] vs 2.3% [n = 23], P = .04). None of the preoperative variables were independent predictors of conversion on multivariate regression analysis. CONCLUSIONS: Because emergency conversion to cardiopulmonary bypass during attempted off-pump coronary bypass surgery results in significantly higher morbidity and mortality, studies comparing off-pump coronary bypass surgery with conventional coronary artery surgery should include converted patients in the off-pump group. In our experience, emergency conversion is an unpredictable event. The incidence of conversion decreases with increasing experience of surgeons in performing off-pump coronary surgery and use of a cardiac positioning device.

Is the impact of hospital and surgeon volumes on the in-hospital mortality rate for coronary artery bypass graft surgery limited to patients at high risk?

BACKGROUND: Restriction of volume-based referral for CABG surgery to high-risk patients has been suggested, and earlier studies have reached different conclusions regarding volume-based referral for low-risk patients. METHODS AND RESULTS: Patients who underwent isolated CABG surgery in New York from 1997 through 1999 (n=57 150) were separated into low-risk and moderate-to-high-risk groups with a predicted probability of in-hospital death of 2% as the cutoff point. The provider volume-mortality relationship was examined for both groups. For annual hospital volume thresholds between 200 and 600 cases, the adjusted ORs of in-hospital mortality for high-volume to low-volume hospitals ranged from 0.45 to 0.77 and were all significant for the low-risk group; for the moderate-to-high-risk group, ORs ranged from 0.62 to 0.91, and most were significant. The number needed to treat at higher-volume hospitals to avoid 1 death was greater for the low-risk group (a range of 114 to 446 versus 37 to 184). As the annual surgeon volume threshold increased from 50 to 150 cases, the ORs for high- to low-volume surgeons increased from 0.43 to 0.74 for the low-risk group; for the moderate-to-high-risk group, ORs ranged from 0.79 to 0.86. Compared with patients treated by surgeons with volumes of <125 in hospitals with volumes of <600, patients treated by higher-volume surgeons in higher-volume hospitals had a significantly lower risk of death; in particular, the OR was 0.52 for the low-risk group. CONCLUSIONS: For both low-risk and moderate-to-high-risk patients, higher provider volume is associated with lower risk of death.

First robotic endoscopic epicardial isolation of the pulmonary veins with microwave energy in a patient in chronic atrial fibrillation.

The pulmonary veins have been demonstrated to play an important role in generating atrial fibrillation. We report the first successful endoscopic epicardial isolation of the pulmonary veins in a patient with permanent atrial fibrillation, along with a 1-year follow-up. The procedure consisted of making a conduction block around the pulmonary veins with a flexible microwave energy delivery probe. The probe was placed endoscopically on the left atrial epicardium with the aid of robotic instruments.

A comparison of short- and long-term outcomes after off-pump and on-pump coronary artery bypass graft surgery with sternotomy.

OBJECTIVES: This study was designed to compare in-hospital mortality and complications and three-year mortality and revascularization for off-pump and on-pump coronary artery bypass graft (CABG) surgery after adjusting for patient risk. BACKGROUND: The use of off-pump CABG surgery has increased tremendously in recent years, but little is known about its long-term outcomes relative to on-pump CABG surgery, and most studies have been very small. METHODS: Short- and long-term outcomes (inpatient mortality and complications, three-year risk-adjusted mortality, and mortality/revascularization) were explored for patients who underwent off-pump CABG surgery (9135 patients) and on-pump CABG surgery (59044 patients) with median sternotomy from 1997 to 2000 in the state of New York. RESULTS: Risk-adjusted inpatient mortality was 2.02% for off-pump versus 2.16% for on-pump (p = 0.390). Off-pump patients had lower rates of perioperative stroke (1.6% vs. 2.0%, p = 0.003) and bleeding requiring reoperation (1.6% vs. 2.2%, p < 0.001) and higher rates of gastrointestinal bleeding, perforation, or infarction (1.2% vs. 0.9%, p = 0.003). Off-pump patients had lower postoperative lengths of stay (median 5 days vs. 6 days, p < 0.001). On-pump patients had higher three-year survival (adjusted risk ratio [RR] =1.086, p = 0.045) and higher freedom from death or revascularization (adjusted RR = 1.232, p < 0.001). When analyses were limited to 1999 to 2000, the two-year adjusted hazard ratio for survival was not significant (adjusted RR = 0.99, p = 0.81). CONCLUSIONS: On-pump patients experience better long-term survival and freedom from revascularization than off-pump patients. However, the survival benefit from on-pump procedures was no longer present in the last two years of the study.

Do hospitals and surgeons with higher coronary artery bypass graft surgery volumes still have lower risk-adjusted mortality rates?

BACKGROUND: Studies that are the basis of recommended volume thresholds for CABG surgery are outdated and not reflective of recent advances in the field. This study examines both hospital and surgeon volume-mortality relations for CABG surgery through the use of a population-based clinical data set. METHODS AND RESULTS: Data from New York's clinical CABG surgery registry from 1997 to 1999 (total number of procedures, 57 150) were used to examine the individual and combined impact of annual hospital volume and annual surgeon volume on in-hospital mortality rates after adjusting for differences in severity of illness. Significantly lower risk-adjusted mortality rates occurred above all annual hospital volume thresholds between 200 and 800 and above all surgeon volume thresholds between 50 and 200. The number needed to treat (NNT) at higher-volume providers to avoid a death was minimized for a hospital threshold volume of 100 (NNT=50) and a surgeon threshold volume of 50 (NNT=118). The risk-adjusted mortality rate (RAMR) for patients undergoing surgery performed by surgeons with volumes of > or =125 in hospitals with volumes of > or =600 was 1.89%. The RAMR was significantly higher (2.67%) for patients undergoing surgery performed by surgeons with volumes of <125 in hospitals with volumes of <600. CONCLUSIONS: Higher-volume surgeons and hospitals continue to have lower risk-adjusted mortality rates, and patients undergoing surgery performed by higher-volume surgeons in higher-volume hospitals have the lowest mortality rates.