Emergent TandemHeart-ECMO for acute severe mitral regurgitation with cardiogenic shock and hypoxaemia: a case series.

BACKGROUND: Acute severe mitral regurgitation (MR) associated with cardiogenic shock is a life-threatening emergency. Traditional teaching has focused on the need for emergent coronary angiography and/or intra-aortic balloon counterpulsation in preparation for emergent open-heart surgery for repair/replacement. Unfortunately, emergent open-heart surgery in patients with acute MR complicated by cardiogenic shock is associated with 25-46% perioperative mortality. New devices have provided additional options for stabilization prior to emergent surgery which facilitate improved outcomes. CASE SUMMARY: We present two cases of acute severe MR resulting in cardiogenic shock and profound hypoxaemia. TandemHeart® mechanical circulatory support with an oxygenator spliced into the circuit, akin to veno-arterial extracorporeal membrane oxygenation (ECMO), facilitated haemodynamic stabilization and decongestion of the lungs facilitating successful bridge to mitral valve surgery. Successful discharge to home was achieved in both patients with good neurological outcomes and sustained long-term functional recovery at 18 and 14 months, respectively. DISCUSSION: Selective use of the TandemHeart®, with or without ECMO, facilitates management of the critically ill cardiogenic shock patient with acute severe MR.

Outcomes following emergent open repair for thoracic aortic dissection are improved at higher volume centers in direct admissions and transfers.

BACKGROUND: The purpose of this study is (1) to define the proportion of patients undergoing emergent open repair of thoracic aortic dissection admitted directly through the emergency room versus those transferred from outside hospitals and (2) to determine if a volume-outcomes relationship exists for those patients across admission types. METHODS: De-identified patient-level data was obtained from the Nationwide Inpatient Sample (2004-2008). Patients undergoing emergent aortic surgery for thoracic aortic dissection (n = 1,507) were identified by ICD-9 codes and stratified by annual center volume into low volume (≤5 cases/year) (n = 963; 63.9 %), intermediate volume (6-10 cases/year) (n = 370; 24.5 %), and high volume (≥11 cases/year) (n = 174; 11.6 %) groups. The analysis was further stratified by admission type: direct admission (DA), transfer admission (TA), and other. The primary outcome was in-hospital mortality. Multivariate logistic regression analysis was performed comparing outcomes between high vs low and high vs intermediate volume centers. RESULTS: Overall in-hospital mortality was 21.8 % (n = 328/1,507). Absolute percent mortality at high volume centers was significantly lower (12.6 %) than at medium (20.6 %) and low volume (23.9 %) centers. For DA patients, mortality was 10.6, 21.4, and 24.0 % for high, medium, and low volume centers respectively. For TA patients, mortality was 10.2, 12.7, and 23.5 % for high, medium, and low volume centers, respectively. Multivariate analysis suggested that patients in low volume center were more likely to die compared to high volume center (Odds Ratio 2.06, 95 % CI 1.25 - 3.38, p = 0.004). Admission source was not associated with increased mortality. CONCLUSIONS: Direct admissions comprise the largest proportion of dissections regardless of volume strata, and they comprise the largest proportion in the low and intermediate volume cohorts. Admission to low volume center is an independent risk factor for increased mortality. Patients transferred to high volume centers from low volume centers have similar outcome as direct admits in terms of mortality.

The impact of age and severity of comorbid illness on outcomes after isolated aortic valve replacement for aortic stenosis.

OBJECTIVES: This study examines outcomes in a national sample of patients undergoing isolated aortic valve replacement (AVR) for aortic stenosis, with particular focus on advanced-age patients and those with extreme severity of comorbid illness (SOI). METHODS: Data were obtained from the Nationwide Inpatient Sample and included all patients undergoing AVRs performed from January 1, 2006 to December 31, 2008. Patients with major concomitant cardiac procedures, as well as those aged, 20 years, and those with infective endocarditis or aortic insufficiency without aortic stenosis, were excluded from analysis. The analysis included 13,497 patients. Patients were stratified by age and further stratified by All Patient Refined Diagnosis Related Group SOI into mild/moderate, major, and extreme subgroups. RESULTS: Overall in-hospital mortality was 2.96% (n=399); in-hospital mortality for the ≥80-year-old group (n=139, 4.78%) was significantly higher than the 20- to 49-year-old (n=9, 0.84%, P<0.001) or 50- to 79-year-old (n=251, 2.64%, P<0.001) groups. In-hospital mortality was significantly higher in the extreme SOI group (n=296, 15.33%) than in the minor/moderate (n=22, 0.35%, P<0.001) and major SOI groups (n=81, 1.51%, P<0.001). Median in-hospital costs in the mild/moderate, major, and extreme SOI strata were $29,202.08, $36,035.13, and $57,572.92, respectively. CONCLUSION: In the minor, moderate, and major SOI groups, in-hospital mortality and costs are low regardless of age; these groups represent >85% of patients undergoing isolated AVR for aortic stenosis. Conversely, in patients classified as having extreme SOI, surgical therapy is associated with exceedingly high inpatient mortality, low home discharge rates, and high resource utilization, particularly in the advanced age group.

Outcomes following emergent open repair for thoracic aortic dissection are improved at higher volume centers.

BACKGROUND: Previous studies have demonstrated that patients undergoing complex surgical procedures at high-volume centers have improved outcomes. The goal of this study was to determine if this volume-outcomes relationship persists at a national level among patients undergoing emergent open repair for thoracic aortic dissection. METHODS: De-identified patient-level data were obtained from the Nationwide Inpatient Sample (2005 to 2008). Patients undergoing emergent aortic surgery for thoracic aortic dissection (n = 1230) were identified by ICD-9 codes and stratified by annual center volume into low volume (≤5 cases/year), intermediate volume (6 to 10 cases/year), and high volume (≥11 cases/year). The Deyo-Charlson co-morbidity score was used to adjust for differences in comorbidity between groups. Major outcomes of interest included: in-hospital morbidity and mortality, length of hospitalization, total hospital costs, and discharge disposition. RESULTS: There was a significant association between in-hospital mortality and center volume (p = 0.014), with low, intermediate, and high-volume centers having mortality rates of 23.4% (n = 187), 20.1% (n = 62), and 12.1% (n = 15), respectively. This relationship persisted when controlling for severity of co-morbid illness (p = 0.007). The number of complications per patient varied significantly by center volume (p = 0.044), with a higher proportion of patients at high-volume centers having no complications. Also, the highest proportion of home discharges was observed among patients at high-volume centers (p = 0.011). CONCLUSIONS: Survival following emergent open repair for thoracic aortic dissection was significantly greater at high-volume centers. These findings suggest that understanding the processes at high-volume centers that underlie this volume-outcomes relationship may improve in-hospital survival and postoperative complications.

Successful Management of Thrombosis of the Proximal Aorta after Implantation with a Biventricular Assist Device.

Continuous-flow ventricular assist devices (CVADs) are associated with a significant complication profile that includes thrombosis of the ascending aorta and aortic valve, thromboembolism, and stroke. Despite an increasing number of reports of thromboembolic complications related to CVADs, there is little in the literature to guide their management. This report describes successful management strategies used during two cases of thrombosis of the ascending aorta during biventricular CentriMag (Levitronix LLC, Waltham, MA) support, including using pre-existing cannulas to initiate cardiopulmonary bypass.

Stingray barb injury: a cause of late coronary occlusion and stent failure.

Stingray injuries to the heart are rare, and survivors of this injury are even rarer. To date, there are only three reported survivors of this mode of penetrating cardiac injury, all inflicted by the living animal itself. The following is a report of a stingray injury, inflicted by a human, causing coronary complications 17 years after the injury was sustained.

Kernel regression for fMRI pattern prediction.

This paper introduces two kernel-based regression schemes to decode or predict brain states from functional brain scans as part of the Pittsburgh Brain Activity Interpretation Competition (PBAIC) 2007, in which our team was awarded first place. Our procedure involved image realignment, spatial smoothing, detrending of low-frequency drifts, and application of multivariate linear and non-linear kernel regression methods: namely kernel ridge regression (KRR) and relevance vector regression (RVR). RVR is based on a Bayesian framework, which automatically determines a sparse solution through maximization of marginal likelihood. KRR is the dual-form formulation of ridge regression, which solves regression problems with high dimensional data in a computationally efficient way. Feature selection based on prior knowledge about human brain function was also used. Post-processing by constrained deconvolution and re-convolution was used to furnish the prediction. This paper also contains a detailed description of how prior knowledge was used to fine tune predictions of specific "feature ratings," which we believe is one of the key factors in our prediction accuracy. The impact of pre-processing was also evaluated, demonstrating that different pre-processing may lead to significantly different accuracies. Although the original work was aimed at the PBAIC, many techniques described in this paper can be generally applied to any fMRI decoding works to increase the prediction accuracy.

Multivessel off-pump revascularization in patients with significant left main coronary artery stenosis: early and midterm outcome analysis.

BACKGROUND: The presence of significant left main stenosis (> or =50%) has been considered a relative contraindication to the use of off-pump coronary artery bypass (OPCAB) stemming from well-documented hemodynamic perturbations during the displacement of the heart. We examined our experience with patients with critical left main stenosis (LMS) to assess the safety and feasibility of OPCAB in this subgroup. METHODS: Our prospectively updated database was queried to identify all patients with severe left main disease who underwent isolated coronary revascularization between January 1, 1999 and May 31, 2002. This query yielded 234 on-pump and 420 off-pump patients with significant LMS whose clinical information was retrospectively reviewed. RESULTS: The groups were well matched with regard to gender, left ventricular function, surgical priority, and severity of angina. The conventional coronary artery bypass (CABG) group was significantly younger than the OPCAB group and had a higher incidence of a previous myocardial infarction. Patients in the CABG cohort were more likely than OPCAB patients to remain ventilated after 24 hours, require placement of intraoperative or postoperative intraaortic balloon pump, or suffer from postoperative renal failure. There was a decrease in mortality (6.4% vs. 1.9%; p = 0.006) when CPB was eliminated. Intermediate term survival analysis revealed a significant survival benefit in the off-pump group (p = 0.007). CONCLUSIONS: Multivessel off-pump revascularization in patients with severe left main disease is a safe and effective alternative to conventional bypass grafting and conveys a survival benefit.

Is off-pump revascularization better for patients with non-dialysis-dependent renal insufficiency?

BACKGROUND: Renal dysfunction is a well-recognized complication following coronary artery bypass grafting (CABG). Coronary revascularization without cardiopulmonary bypass (CPB) has been shown to minimize renal injury in patients with normal preoperative renal function who undergo elective procedures. The purpose of this study was to define the effect of an off-pump revascularization strategy on the incidence of postoperative renal failure and survival of patients with preexisting renal dysfunction. METHODS: From January 1, 1999, to December 1, 2002, a total of 371 patients were identified as having a preoperative creatinine concentration greater than or equal to 1.5 mg/dL. This number included 291 patients who did not need hemodialysis or peritoneal dialysis to support renal function. These patients were subdivided into those undergoing traditional CABG with CPB (103 patients) and those undergoing off-pump revascularization (188 patients) whose demographic, operative, and outcome information was retrospectively reviewed and compared. RESULTS: The off-pump cohort was older than the on-pump cohort (70 +/- 9.6 versus 66 +/- 10.9 years; P =.002), had a lower prevalence of previous myocardial infarction (35% versus 50%; P =.008), and had a modestly higher mean left ventricular ejection fraction (0.47 +/- 0.01 versus 0.43 +/- 0.01; P =.017). Otherwise the groups were well matched. The mean preoperative serum creatinine and creatinine clearance values were not significantly different (1.8 +/- 0.5 versus 1.9 +/- 0.6 mg/dL [ P =.372] and 45.1 +/- 15.5 versus 46.8 +/- 17.2 mL/min [ P =.376] for the off-pump and on-pump cohorts, respectively). There was a significant reduction in postoperative renal failure (17% versus 9% of patients; P =.020) and need for new dialysis (10% versus 3% of patients; P =.022) when CPB was eliminated. Intermediate-term survival analysis revealed a survival benefit for the off-pump group (70% versus 57%) at 42 months, although this value did not reach statistical significance ( P =.143). CONCLUSION: The results of this study suggested that patients with preoperative non-dialysis-dependent renal insufficiency have more favorable outcome when revascularization is done off pump. Avoidance of CPB results in (1) a reduction in the incidence of postoperative renal failure; (2) a reduction in the need for new dialysis; and (3) improved in-hospital and midterm survival.

Multivessel off-pump revascularization in patients with severe left ventricular dysfunction.

OBJECTIVE: The purpose of this study was to investigate the safety and efficacy of multivessel beating heart revascularization in a high-risk group of patients with severe left ventricular dysfunction as well as to provide intermediate survival and quality of life data. METHODS: Our prospectively updated database was queried to extract all patients with left ventricular ejection fraction < or =30% who underwent beating heart revascularization. Standard demographics, clinical profiles and outcomes were collected. Outcomes were compared with Society of Thoracic Surgeons (STS) benchmarks for all coronary artery bypass grafting (CABG) patients. Telephone interviews were conducted and survival and quality of life data were tabulated. In addition, morbidity and mortality outcomes were compared with a concurrent cohort of patients with similarly impaired left ventricular function who underwent conventional coronary artery bypass. RESULTS: One hundred off-pump coronary artery bypass grafting patients were identified and follow-up was 93% complete in these patients. Mean age was 67+/-10.5 years and mean ejection fraction was 26+/-4%. Twenty-one percent were females. Balloon counterpulsation support was used liberally in the perioperative period. Patients received a mean of 3.5 grafts with 83% internal mammary artery use. Observed mortality was 3% with a predicted mortality of 5.3%. Observed to expected ratio was 0.56. Incidence of adverse events compared favorably with both that reported in the STS for all CABG patients regardless of left ventricular function, and also to a concurrent CABG cohort. One-year survival was 85%. Freedom from cardiac readmission was 88% and freedom from angina was 83%. No patient required repeat percutaneous or surgical intervention. CONCLUSIONS: We conclude that multivessel off-pump revascularization in patients with severe left ventricular dysfunction is a safe and effective alternative to conventional grafting. Long-term follow-up is mandatory to confirm these encouraging intermediate outcomes.

Multivessel off-pump revascularization in octogenarians: early and midterm outcomes.

BACKGROUND: Octogenarians are increasingly being referred for coronary artery revascularization. However, the prevalence of comorbid events and the propensity for neurologic dysfunction place octogenarians at higher risk for cardiopulmonary bypass-induced morbidity and mortality. Therefore, octogenarian patients represent a particularly attractive target for application of off-pump coronary artery bypass grafting. METHODS: From January 1999 to August 2001, 113 octogenarians had off-pump coronary artery bypass grafting. Their data were prospectively entered into the cardiac surgery database and analyzed retrospectively. Follow-up information was obtained through telephone survey. RESULTS: The mean age of the patients was 83 +/- 2.5 years, and the mean number of grafts per patient was 3.3 +/- 1. The most prevalent postoperative complication was atrial fibrillation (43%). Postoperative neurologic complications were seen in 5 patients (4%). There was one postoperative death (30-day mortality rate, 0.9%). The mean follow-up was 13.2 +/- 7 months and was complete for 90% of the patients. At the time of telephone survey, 85 (87%) of 98 patients were free from angina, and 91 (88%) were free from cardiac-related readmission. There were three late deaths. The majority of octogenarians (66%) reported that in retrospect, they would have the operation again. CONCLUSIONS: Off-pump multivessel revascularization in octogenarians is associated with excellent early and intermediate outcomes and provides a satisfactory quality of life.