Faculty Bibliography

Objective: The purpose of this study was to compare operative strategies and patient outcomes in acute type A aortic dissection (ATAAD) repairs before and after the implementation of a multidisciplinary aortic surgery program. Methods: Between May, 2005, and July, 2014, 101 patients underwent ATAAD repair at our institution. A dedicated multidisciplinary aortic surgery team (experienced aortic surgeon, perfusionists, cardiac anesthesiologists, nurses, radiologists) was formed in 2010. We retrospectively compared ATAAD repair outcomes in patients before (2005-2009, n=39) and after (2010-2014, n=62) the implementation of our program. Expected operative mortality was calculated using the International Registry of Acute Aortic Dissection (IRAD) preoperative prediction model. Results: This study demonstrated a significant reduction in operative mortality after implementation of the aortic surgery program (30.8% vs. 9.7%; P=0.014). There was also an increase in the complexity of surgical technique and perfusion strategies with fewer postoperative complications related to respiratory (P<0.0001) and renal failure (P=0.034). No statistical difference in baseline demographics and IRAD-predictive variables were noted between groups (Table SA17-1). However, there was a 3.5-fold reduction in the observed to- expected (O/E) operative mortality ratio (1.52-0.44) (Fig. SA17-1). The success of the aortic program resulted in a 50%increase in volume with a significant number of patients being admitted directly to our aortic center for ATAAD repair, thus avoiding delays related to transfer from a secondary hospital. Conclusions: Patient outcomes can be improved if the surgical treatment of ATAAD were restricted to institutions with a high-volume multidisciplinary aortic surgery program. (Figure Presented)

OBJECTIVE: Immediate extubation of select patients in the operating room after cardiac surgery has been shown to be safe and may result in improved hemodynamics and decreased cost perioperatively. The aim of this study was to evaluate whether the addition of paravertebral blockade (PVB) to general anesthesia facilitates extubation in the operating room in patients undergoing totally endoscopic robotic mitral valve repair (TERMR). METHODS: A review of 65 consecutive patients who underwent TERMR between January 2012 and June 2013 at a single institution was conducted. Patients were divided into two groups, one group that received PVB and general anesthesia and a second group that received general anesthesia alone. The data analyzed included quantities of anesthetic administered during surgery and the location of extubation after surgery. RESULTS: A total of 34 patients received PVB and general anesthesia, whereas 31 received general anesthesia alone. The two groups had similar demographic and surgical data. Patients in the PVB and general anesthesia group were more likely to be extubated in the operating room (67.6%, n = 23 vs 41.9%, n = 13, P = 0.048) and required less intraoperative fentanyl (3.41 mug/kg vs 4.90 mug/kg, P = 0.006). There were no adverse perioperative events in either group related to PVB or extubation. CONCLUSIONS: The addition of PVB to general anesthesia for perioperative pain control facilitated extubation in the operating room in patients undergoing TERMR. Paravertebral blockade allowed for lower intraoperative fentanyl dosing, which may account for the increased incidence of immediate extubation. A detailed prospective study is warranted.

OBJECTIVE: The present study aimed to evaluate the effect of blood conservation strategies on patient outcomes after aortic surgery. DESIGN: Retrospective cohort analysis of prospective data. SETTING: University hospital. PARTICIPANTS: Patients undergoing thoracic aortic surgery. INTERVENTIONS: One hundred thirty-two consecutive high-risk patients (mean EuroSCORE 10.4%) underwent thoracic aortic aneurysm or dissection repair from January 2010 to September 2011. A blood conservation strategy (BCS) focused on limitation of hemodilution and tolerance of perioperative anemia was used in 57 patients (43.2%); the remaining 75 (56.8%) patients were managed by traditional methods. Mortality, major complications, and red blood cell transfusion requirements were assessed. Independent risk factors for clinical outcomes were determined by multivariate analyses. MEASUREMENTS AND MAIN RESULTS: Hospital mortality was 9.8% (13 of 132). Lower preoperative hemoglobin was an independent predictor of mortality (p<0.01, odds ratio [OR] 1.7). Major complications were associated with perioperative transfusion: 0% complication rate in patients receiving<2 units of packed red blood cells versus 32.3% (20 of 62) in patients receiving>/=2 units. The blood conservation strategy had no significant impact on mortality (p = 0.4) or major complications (p = 0.9) despite the blood conservation patients having a higher incidence of aortic dissection and urgent/emergent procedures and lower preoperative and discharge hemoglobin. In patients with aortic aneurysms, BCS patients received 1.5 fewer units of red blood cells (58% reduction) than non-BCS patients (p = 0.01). Independent risk factors for transfusion were lower preoperative hemoglobin (p<0.01, OR 1.5) and lack of BCS (p = 0.02, OR 3.6). CONCLUSIONS: Clinical practice guidelines for blood conservation should be considered for high-risk complex aortic surgery patients.

OBJECTIVE: Although the technique of totally endoscopic robotic mitral valve repair (TERMR) has been well described, few reports have examined the results of peripheral perfusion with balloon clamping. We analyzed the outcomes of TERMR performed using this strategy. METHODS: A total of 108 consecutive patients underwent TERMR by a 2-surgeon team. The preoperative evaluation included chest computed tomography and abdominal and pelvis computed tomography. Additional procedures included appendage exclusion in 96, patent foramen ovale closure in 29, cryoablation in 16, tricuspid valve repair in 2, and septal myectomy in 2. The mean patient age was 59 years (range, 21-86). Central venous drainage was obtained with a long cannula. Arterial return was achieved with femoral cannulation, when possible. An endoballoon catheter was placed through the femoral artery. Transesophageal echocardiography was used to position all catheters. RESULTS: Femoral artery perfusion was possible in 103 of 108 patients (95.3%). The subclavian artery was used in 5 patients (4.6%) with contraindications to retrograde perfusion. An endoballoon clamp was placed by way of the femoral artery. In 105 of 108 patients (97.2%), endoaortic occlusion was successfully used; the mean crossclamp time was 87.4 minutes. The coronary sinus cardioplegia catheter was placed successfully in 81 of the 108 patients (75%). Postoperatively, no or mild inotropic support was needed in 94 (87%) and moderate support in 14 (13.0%). Of the 108 patients, 55 (50.9%) were extubated in the operating room. No hospital mortality, aortic injury, vascular complications, or wound infections occurred. Complications included 2 strokes (no residual deficit) (1.8%) and atrial fibrillation in 18 (16.7%). The median hospital stay was 4 days. Eighty patients (74.1%) were discharged by postoperative day 5. CONCLUSIONS: A preoperative image-guided perfusion strategy and aortic balloon clamping permit routine TERMR with excellent myocardial preservation and minimal complications.

Abstract Background: Large institutional analyses demonstrating outcomes of right anterior mini-thoracotomy (RAT) for isolated aortic valve replacement (isoAV) do not exist. In this study, a group of cardiac surgeons who routinely perform minimally invasive isoAVR analyzed a cross-section of US hospital records in order to analyze outcomes of RAT as compared to sternotomy. Methods: The Premier database was queried from 2007-2011 for clinical and cost data for patients undergoing isoAVR. This de-identified database contains billing, hospital cost, and coding data from >600 US facilities with information from >25 million inpatient discharges. Expert rules were developed to identify patients with RAT and those with any sternal incision (aStern). Propensity matching created groups adjusted for patient differences. Impact of surgical approach on outcomes and costs were modeled using regression analysis and, where indicated, adjusting for hospital size and geographical differences. Results: AVR was performed in 27,051 patients. Analysis identified isoAVR by RAT (n=1,572) and by aStern (n=3,962). Propensity matching created two groups of 921 patients. RAT was more likely performed in southern hospitals (63% vs 36%; p<0.01), teaching hospitals (66% vs 58%; p<0.01) and larger hospitals (47% vs 30%; p<0.01). There was significantly less blood product cost associated with RAT ($1,381 vs $1,912; p<0.001). After adjusting for hospital differences, RAT was associated with lower cost than aStern ($38,769 vs $42,656; p<0.01). Conclusions: Outcomes analyses can be performed from hospital administrative collective databases. This real world analysis demonstrates comparable outcomes and less cost and ICU time with RAT for AVR.

OBJECTIVE: Systolic anterior motion (SAM) can occur after mitral valve repair (MVr), most frequently in patients with degenerative valve disease. Our initial observations (1981-1990) revealed that most patients with SAM can be successfully treated medically. Here the authors review the last 16 years of their experience with SAM after MVr. METHODS: Between January 1996 and October 2011, 1918 patients with degenerative mitral valve disease underwent MVr at our institution. We performed a retrospective analysis of SAM in this patient population. RESULTS: The incidence of SAM was 4.6% (89 of 1918) overall, 4.0% (77 of 1906) in patients who did not have SAM preoperatively (de novo). Compared with our previously published report, the incidence of SAM decreased from 6.4% to 4.0% (P = .03). Hospital mortality was 2.0% (38 of 1918) overall, 1.3% (14 of 1078) for isolated MVr. One patient with de novo SAM (1 of 77; 1.3%) died after emergency MVr. All patients with de novo SAM were successfully managed conservatively with intravenous fluids, alpha agonists, and/or beta blockers. A higher incidence of SAM was associated with a left ventricular ejection fraction greater than 60% (P = .01), posterior leaflet resection (P = .048), and hypertrophic obstructive cardiomyopathy (P < .01). The incidence of SAM was lower in patients who underwent device mitral annuloplasty with a semirigid posterior band compared with a complete ring (P = .03). CONCLUSIONS: In the more recent era, SAM occurs one-third less frequently after repair of degenerative mitral valve disease. Use of an incomplete annuloplasty band rather than a complete ring is associated with a lower incidence of SAM. The mainstay treatment of SAM continues to be medical management.

OBJECTIVE: Small series of thoracotomy for mitral valve repair have demonstrated clinical benefit. This multi-institutional administrative database analysis compares outcomes of thoracotomy and sternotomy approaches for mitral repair. METHODS: The Premier database was queried from 2007 to 2011 for mitral repair hospitalizations. Premier contains billing, cost, and coding data from more than 600 US hospitals, totaling 25 million discharges. Thoracotomy and sternotomy approaches were identified through expert rules; robotics were excluded. Propensity matching on baseline characteristics was performed. Regression analysis of surgical approach on outcomes and costs was modeled. RESULTS: Expert rule analysis positively identified thoracotomy in 847 and sternotomy in 566. Propensity matching created 2 groups of 367. Mortalities were similar (thoracotomy 1.1% vs sternotomy 1.9%). Sepsis and other infections were significantly lower with thoracotomy (1.1% vs 4.4%). After adjustment for hospital differences, thoracotomy carried a 17.2% lower hospitalization cost (-$8289) with a 2-day stay reduction. Readmission rates were significantly lower with thoracotomy (26.2% vs 35.7% at 30 days and 31.6% vs 44.1% at 90 days). Thoracotomy was more common in southern and northeastern hospitals (63% vs 37% and 64% vs 36%, respectively), teaching hospitals (64% vs 36%) and larger hospitals (>600 beds, 78% vs 22%). CONCLUSIONS: Relative to sternotomy, thoracotomy for mitral repairs provides similar mortality, less morbidity, fewer infections, shorter stay, and significant cost savings during primary admission. The markedly lower readmission rates for thoracotomy will translate into additional institutional cost savings when a penalty on hospitals begins under the Affordable Care Act's Hospital Readmissions Reduction Program.

BACKGROUND AND AIM OF THE STUDY: Mitral annuloplasty (MA) devices are available in different shapes and sizes, but the preferred shape and size are unclear. METHODS: A previously described and validated finite element (FE) model of the left ventricle (LV) with mitral valve (MV) based on magnetic resonance imaging and three-dimensional echocardiography images from a patient with posterior leaflet (PL; P2) prolapse was used in this study. FE models of MA devices with different shapes (flat partial, shallow saddle, pronounced saddle) and sizes (36-30) were created. Virtual leaflet resection + MA with each shape and size were simulated. Leaflet geometry, stresses in the leaflets and base of the LV, and forces in the chordae and MA sutures were calculated. RESULTS: All MA shapes increased the mitral coaptation length, reduced the elevated PL stress at end-diastole (ED) and end-systole (ES) that occurred after leaflet resection, and reduced anterior leaflet (AL) stress at ES. MA devices of all shapes and sizes modestly reduced myofiber stress at the LV base in ED and ES. In general, saddle-shaped devices had the greatest effect. CONCLUSION: All MA shapes increased coaptation length and reduced mitral leaflet stress and myofiber stress in the base of the LV. an additional reduction in MA size further increased coaptation length and reduced leaflet and myofiber stress. In general, saddle-shaped devices had the greatest effect.

BACKGROUND: The role of posterior papillary muscle anchoring (PPMA) in the management of chronic ischemic mitral regurgitation (CIMR) is controversial. We studied the effect of anchoring point direction and relocation displacement on left ventricular (LV) regional myofiber stress and pump function. METHODS: Previously described finite element models of sheep 16 weeks after posterolateral myocardial infarction (MI) were used. True-sized mitral annuloplasty (MA) ring insertion plus different PPM anchoring techniques were simulated. Anchoring points tested included both commissures and the central anterior mitral annulus; relocation displacement varied from 10% to 40% of baseline diastolic distance from the PPM to the anchor points on the annulus. For each reconstruction scenario, myofiber stress in the MI, border zone, and remote myocardium as well as pump function were calculated. RESULTS: PPMA caused reductions in myofiber stress at end-diastole and end-systole in all regions of the left ventricle that were proportional to the relocation displacement. Although stress reduction was greatest in the MI region, it also occurred in the remote region. The maximum 40% displacement caused a slight reduction in LV pump function. However, with the correction of regurgitation by MA plus PPMA, there was an overall increase in forward stroke volume. Finally, anchoring point direction had no effect on myofiber stress or pump function. CONCLUSIONS: PPMA reduces remote myofiber stress, which is proportional to the absolute distance of relocation and independent of anchoring point. Aggressive use of PPMA techniques to reduce remote myofiber stress may accelerate reverse LV remodeling without impairing LV function.