Concomitant temporary mechanical support in high-risk coronary artery bypass surgery.

OBJECTIVES: Patients with low left ventricular ejection fraction (LVEF) undergoing high-risk coronary artery bypass grafting (CABG) are at increased risk for postcardiotomy cardiogenic shock. This report describes planned concomitant microaxial temporary mechanical support (MA-TMS) device placement as a viable bridge-to-recovery strategy for high-risk patients receiving surgical revascularization. METHODS: A retrospective review was performed for all patients from October 2017 to May 2019 with low LVEF (<30%), New York Heart Association Class III or IV symptoms, and myocardial viability who underwent CABG with prophylactic MA-TMS support at a single institution (n = 13). RESULTS: Mean patient age was 64.8 years, and 12 patients (92%) were male. Eight patients (62%) presented with acute coronary syndrome. Mean predicted risk of mortality was 4.6%, ranging from 0.6% to 15.6%. An average of 3.4 grafts were performed per patient. Greater than 60% of patients were extubated within 48 hours and out-of-bed within 72 hours, and the average duration of MA-TMS was 5.7 days. Mean postoperative length of stay was 16.7 days. There were no postoperative myocardial infarctions or deaths. CONCLUSIONS: Prophylactic MA-TMS may allow safe and effective surgical revascularization for patients with severe left ventricular dysfunction who may otherwise be offered a durable ventricular assist device.

Del Nido cardioplegia for minimally invasive aortic valve replacement.

BACKGROUND: We analyzed the impact and safety of del Nido Cardioplegia (DNC) in patients undergoing minimally invasive aortic valve replacement (MIAVR). METHODS: We analyzed all isolated MIAVR replacements from 5/2013-6/2015 excluding re-operative patients. The approach was a hemi-median sternotomy in all patients. Patients were divided into two cohorts, those who received 4:1 crystalloid:blood DNC solution and those in whom standard 1:4 Buckberg-based cardioplegia (WBC) was used. One-to-one propensity case matching of DNC to WBC was performed based on standard risk factors and differences between groups were analyzed using chi-square and non-parametric methods. RESULTS: MIAVR was performed in 181 patients; DNC was used in 59 and WBC in 122. Case matching resulted in 59 patients per cohort. DNC was associated with reduced re-dosing (5/59 (8.5%) versus 39/59 (61.0%), P < 0.001) and less total cardioplegia volume (1290 ± 347 mL vs 2284 ± 828 mL, P < 0.001). Antegrade cardioplegia alone was used in 89.8% (53/59) of DNC patients versus 33.9% (20/59) of WBC patients (P < 0.001). Median bypass and aortic cross-clamp times were similar. Clinical outcomes were similar with respect to post-operative hematocrit, transfusion requirements, need for inotropic/pressor support, duration of intensive care unit stay, re-intubation, length of stay, new onset atrial fibrillation, and mortality. CONCLUSIONS: Del Nido cardioplegia usage during MIAVR minimized re-dosing and the need for retrograde delivery. Patient safety was not compromised with this technique in this group of low-risk patients undergoing MIAVR.

Long-term results of mitral valve repair with semi-rigid posterior band annuloplasty.

BACKGROUND AND AIM OF THE STUDY: Optimal repair of the mitral valve involves the implantation of an annuloplasty device to geometrically reshape and/or stabilize the annulus and improve long-term durability. It has been reported previously that trigone-to-trigone semi-rigid posterior band (PB) annuloplasty is associated with excellent short-term outcomes, physiologic motion of the anterior mitral annulus and leaflet, and lower postoperative transvalvular gradients compared to complete ring (CR) annuloplasty. The aim of this retrospective study was to compare the long-term effectiveness of PB and CR annuloplasty in patients with degenerative mitral valve regurgitation (MR). METHODS: Between 1993 and 2010, a total of 1,612 patients with degenerative MR underwent mitral valve repair (MVr) with either PB (n = 1,101) or CR (n = 511). Initially, CR was the annuloplasty device of choice, but after 2001 PB was preferred. A retrospective review of clinical and echocardiographic follow up was performed on these patients. The eight-year cumulative freedom from adverse events were determined by life-table analysis. RESULTS: Hospital mortality was 1.9% overall (n = 30/1612), but 1.3% (12/939) for isolated MVr, and 2.7% (18/673) for MVr with concomitant procedures (p = 0.04). Hospital mortality was similar for both PB (1.9%; 21/1101) and CR (1.8%; 9/511) (p = 0.8). The mean MR grade was reduced from 3.9 +/- 0.3 preoperatively to 0.6 +/- 0.9 at follow up using PB (p < 0.01), and from 3.9 +/- 0.4 to 0.9 +/- 0.9 using CR (p < 0.01). PB was associated with a similar long-term freedom from death (77 +/- 0.03% versus 83 +/- 0.02%; p = 0.4), reoperation (95 +/- 0.01% versus 92 +/- 0.01%; p = 0.06), and reoperation or recurrent severe MR (91 +/- 0.02% versus 92 +/- 0.01%; p = 0.7), and slightly greater freedom from valve-related complications compared to CR (91 +/- 0.02% versus 87 +/- 0.02%; p = 0.02). CONCLUSION: The long-term outcome of mitral valve annuloplasty with PB was comparable to that with CR for degenerative disease. Anterior annuloplasty was found to be unnecessary in this patient population.

Routine Extubation in the Operating Room After Isolated Coronary Artery Bypass.

BACKGROUND: The benefits of fast-track extubation in the intensive care unit (ICU) after cardiac surgery are well established. Although extubation in the operating room (OR) is safe in carefully selected patients, widespread use of this strategy in cardiac surgery remains unproven. This study was designed to evaluate perioperative outcomes with OR vs ICU extubation in patients undergoing nonemergency, isolated coronary artery bypass grafting (CABG). METHODS: The Society of Thoracic Surgeons (STS) data for all single-center patients who underwent nonemergency isolated CABG over a 6-year interval were analyzed. Perioperative morbidity and mortality with ICU vs OR extubation were compared. RESULTS: Between January 1, 2017 and December 31, 2022, 1397 patients underwent nonemergency, isolated CABG; 891 (63.8%) of these patients were extubated in the ICU, and 506 (36.2%) were extubated in the OR. Propensity matching resulted in 414 pairs. In the propensity-matched cohort, there were no differences between the 2 groups in incidence of reintubation, reoperation for bleeding, total operative time, stroke or transient ischemic attack, renal failure, or 30-day mortality. OR-extubated patients had shorter ICU hours (14 hours vs 20 hours; P < .0001), shorter postoperative hospital length of stay (3 days vs 5 days; P < .0001), a greater likelihood of being discharged directly to home (97.3% vs 89.9%; P < .0001), and a lower 30-day readmission rate (1.7% vs 4.1%; P = .04). CONCLUSIONS: Routine extubation in the OR is a feasible and safe strategy for a broad spectrum of patients after nonemergency CABG, with no increase in perioperative morbidity or mortality. Wider adoption of routine OR extubation for nonemergency CABG is indicated.

Early Outcomes of the First 200 US Patients Treated with Impella 5.5: A Novel Temporary Left Ventricular Assist Device.

OBJECTIVE: To report the initial clinical experience with the Impella 5.5® with SmartAssist®, a temporary left ventricular assist device that provides up to 6.2 L/min forward flow, with recent FDA approval for up to 14 days. METHODS: From October 2019 to March 2020, 200 patients at 42 US centers received the Impella 5.5 and entered into the IQ registry, a manufacturer-maintained quality database that captures limited baseline/procedural characteristics and outcomes through device explant. Post hoc subgroup analyses were conducted to assess the role of baseline and procedural characteristics on survival, defined as successful device weaning or bridge to durable therapy. RESULTS: Median patient age was 62 years (range, 13 to 83 years); 83.4% were male. The device was most commonly used for cardiomyopathy (45.0%), acute myocardial infarction complicated by cardiogenic shock (AMICS; 29.0%), and post cardiotomy cardiogenic shock (PCCS; 16.5%). Median duration of support was 10.0 days (range, 0.001 to 64.4 days). Through device explant, overall survival was 74.0%, with survival of 80.0%, 67.2%, 57.6%, and 94.7% in cardiomyopathy, AMICS, PCCS, and others (comprising high-risk revascularization, coronary artery bypass graft, electrophysiology/ablation, and myocarditis), respectively. Patients requiring extracorporeal membrane oxygenation and Impella support (35 patients, 17.5%) had significantly lower survival (51.4% vs 78.8%, P = 0.002). CONCLUSIONS: In the first 200 US patients treated with the Impella 5.5, we observed overall survival to explant of 74%. Survival outcomes were improved compared to historic rates observed with cardiogenic shock, particularly PCCS. Prospective studies assessing comparative performance of this device to conventional strategies are warranted in future.

Unusual Cause of Severe Tricuspid Regurgitation: Tricuspid Leaflet Annular Tear Following Remote Motor Vehicle Accident.

Tricuspid regurgitation (TR) is an uncommon and underdiagnosed complication of blunt chest trauma. Typical mechanisms include torn chordae, papillary muscle rupture, and radial leaflet tear. We describe an unusual case of traumatic TR due to circumferential avulsion of the anterior tricuspid leaflet from the tricuspid annulus and the crucial role of multimodality imaging in its diagnosis and treatment. (Level of Difficulty: Intermediate.).

Downregulation of the hemoglobin scavenger receptor in individuals with diabetes and the Hp 2-2 genotype: implications for the response to intraplaque hemorrhage and plaque vulnerability.

In individuals with diabetes mellitus (DM), the haptoglobin (Hp) genotype is a major determinant of susceptibility to myocardial infarction. We have proposed that this is because of DM and Hp genotype-dependent differences in the response to intraplaque hemorrhage. The macrophage hemoglobin scavenging receptor CD163 plays an essential role in the clearance of hemoglobin released from lysed red blood cells after intraplaque hemorrhage. We sought to test the hypothesis that expression of CD163 is DM and Hp genotype-dependent. CD163 was quantified in plaques by immunohistochemistry, on peripheral blood monocytes (PBMs) by FACS, and as soluble CD163 (sCD163) in plasma by ELISA. In DM plaques, despite an increase in macrophage infiltration, CD163 immunoreactivity was lower, resulting in a dramatic reduction in the percentage of macrophages expressing CD163 (27+/-2% versus 70+/-2%, P=0.0001). In individuals with DM as compared with individuals without DM, the percentage of PBMs expressing CD163 was reduced (3.7+/-0.6% versus 7.1+/-0.9%, P<0.002) whereas soluble plasma CD163 was increased (2.6+/-1.1 microg/mL versus 1.6+/-0.8 microg/mL, P<0.0005). Among DM individuals, the Hp 2-2 genotype was associated with a decrease in the percentage of PBMs expressing CD163 (2.3+/-0.5% versus 5.6+/-1.3%, P=0.01) and an increase in plasma soluble CD163 (3.0+/-0.2 microg/mL versus 2.3+/-0.2 microg/mL, P=0.04). Taken together, these results demonstrate an impaired hemoglobin clearance capacity in Hp 2-2 DM individuals and may provide the key insight explaining the increased incidence of myocardial infarction in this population.

Ninety-Day Readmissions of Bundled Valve Patients: Implications for Healthcare Policy.

Medicare's Bundle Payment for Care Improvement (BPCI) Model 2 groups reimbursement for valve surgery into 90-day episodes of care, which include operative costs, inpatient stay, physician fees, postacute care, and readmissions up to 90 days postprocedure. We analyzed our BPCI patients' 90-day outcomes to understand the late financial risks and implications of the bundle payment system for valve patients. All BPCI valve patients from October 2013 (start of risk-sharing phase) to December 2015 were included. Readmissions were categorized as early (≤30 days) or late (31-90 days). Data were collected from institutional databases as well as Medicare claims. Analysis included 376 BPCI valve patients: 202 open and 174 transcatheter aortic valves (TAVR). TAVR patients were older (83.6 vs 73.8 years; P = 0.001) and had higher Society of Thoracic Surgery predicted risk (7.1% vs 2.8%; P = 0.001). Overall, 18.6% of patients (70/376) had one-or-more 90-day readmission, and total claim was on average 51% greater for these patients. Overall readmissions were more common among TAVR patients (22.4% (39/174) vs 15.3% (31/202), P = 0.052) as was late readmission. TAVR patients had significantly higher late readmission claims, and early readmission was predictive of late readmission for TAVR patients only (P = 0.04). Bundled claims for a 90-day episode of care are significantly increased in patients with readmissions. TAVR patients represent a high-risk group for late readmission, possibly a reflection of their chronic disease processes. Being able to identify patients at highest risk for 90-day readmission and the associated claims will be valuable as we enter into risk-bearing episodes of care agreements with Medicare.

Bone marrow cells differentiate in cardiac cell lineages after infarction independently of cell fusion.

Recent studies in mice have challenged the ability of bone marrow cells (BMCs) to differentiate into myocytes and coronary vessels. The claim has also been made that BMCs acquire a cell phenotype different from the blood lineages only by fusing with resident cells. Technical problems exist in the induction of myocardial infarction and the successful injection of BMCs in the mouse heart. Similarly, the accurate analysis of the cell populations implicated in the regeneration of the dead tissue is complex and these factors together may account for the negative findings. In this study, we have implemented a simple protocol that can easily be reproduced and have reevaluated whether injection of BMCs restores the infarcted myocardium in mice and whether cell fusion is involved in tissue reconstitution. For this purpose, c-kit-positive BMCs were obtained from male transgenic mice expressing enhanced green fluorescence protein (EGFP). EGFP and the Y-chromosome were used as markers of the progeny of the transplanted cells in the recipient heart. By this approach, we have demonstrated that BMCs, when properly administrated in the infarcted heart, efficiently differentiate into myocytes and coronary vessels with no detectable differentiation into hemopoietic lineages. However, BMCs have no apparent paracrine effect on the growth behavior of the surviving myocardium. Within the infarct, in 10 days, nearly 4.5 million biochemically and morphologically differentiated myocytes together with coronary arterioles and capillary structures were generated independently of cell fusion. In conclusion, BMCs adopt the cardiac cell lineages and have an important therapeutic impact on ischemic heart failure.

A Contemporary Approach to Reoperative Aortic Valve Surgery: When is Less, More?

OBJECTIVE: Although the benefits of minimally invasive valvular surgery are well established, the applicability of extending these techniques to reoperative aortic valve surgery is unknown. We evaluated our experience with a minimally invasive approach to this patient population. METHODS: From January 2010 to September 2015, 21 patients underwent reoperative isolated aortic valve replacement via a minimally invasive approach by a single surgeon. All patients had preoperative evaluation with computerized tomography and coronary catheterization. Surgical approaches were right anterior thoracotomy (6/21) or upper hemisternotomy (15/21). Central aortic cannulation was preferred with femoral artery cannulation used in four patients (19%). In patients with left internal mammary artery (LIMA) grafts, no attempt to dissect or occlude the graft was made. Cold blood cardioplegia was administered antegrade (12/21) or retrograde (9/21); systemic cooling with a mean low temperature of 27.5 °C was employed. RESULTS: Mean age was 75.1 years with a range from 33 to 92 years, and 67% (14/21) were male. All procedures were completed with a minimally invasive approach. Mean ± SD cross-clamp time was 51.5 ± 9.2 minutes. Fourteen patients had patent LIMA grafts. No aortic, LIMA, or cardiac injuries occurred. There were no hospital deaths nor occurrences of perioperative myocardial infarction, stroke, wound infection, renal failure, or endocarditis/sepsis. One patient required a reoperation for bleeding. Sixty-two percent of patients were discharged to home; mean ± SD length of stay was 6 ± 3 days. CONCLUSIONS: With appropriate preoperative evaluation and careful surgical planning, a minimally invasive approach to reoperative aortic valve surgery can be performed in a safe and effective manner.

Reengineering valve patients' postdischarge management for adapting to bundled payment models.

BACKGROUND: Bundled Payments for Care Improvement (BPCI) initiatives were developed by Medicare in an effort to reduce expenditures while preserving quality of care. Payment model 2 reimburses based on a target price for 90-day episode of care postprocedure. The challenge for valve patients is the historically high (>35%) 90-day readmission rate. We analyzed our institutional cardiac surgical service line adaptation to this initiative. METHODS: On May 1, 2015, we instituted a readmission reduction initiative (RRI) that included presurgical risk stratification, comprehensive predischarge planning, and standardized postdischarge management led by cardiac nurse practitioners (CNPs) who attempt to guide any postdischarge encounters (PDEs). A prospective database also was developed, accruing data on all cardiac surgery patients discharged after RRI initiation. We analyzed detailed PDEs for all valve patients with complete 30-day follow-up through November 2015. RESULTS: Patients included 219 surgical patients and 126 transcatheter patients. Sixty-four patients had 79 PDEs. Of these 79 PDEs, 46 (58.2%) were guided by CNPs. PDEs were due to fluid overload/effusion (21, 27%), arrhythmia (17, 22%), bleeding/thromboembolic events (13, 16%), and falls/somatic complaints (12, 15%). Thirty-day readmission rate was 10.1% (35/345). Patients with transcatheter aortic valve replacement had a higher rate of readmission than surgical patients (15.0% vs 6.9%), but were older with more comorbidities. The median readmission length of stay was 2.0 days (interquartile range 1.0-5.0 days). Compared with 2014, the 30-day readmission rate for BPCI decreased from 18% (44/248) to 11% (20/175), P = .05. CONCLUSIONS: Our reengineering of pre/postdischarge management of BPCI valve patients under tight CNP control has significantly reduced costly 30-day readmissions in this high-risk population.

Cardiac stem cell and myocyte aging, heart failure, and insulin-like growth factor-1 overexpression.

To determine whether cellular aging leads to a cardiomyopathy and heart failure, markers of cellular senescence, cell death, telomerase activity, telomere integrity, and cell regeneration were measured in myocytes of aging wild-type mice (WT). These parameters were similarly studied in insulin-like growth factor-1 (IGF-1) transgenic mice (TG) because IGF-1 promotes cell growth and survival and may delay cellular aging. Importantly, the consequences of aging on cardiac stem cell (CSC) growth and senescence were evaluated. Gene products implicated in growth arrest and senescence, such as p27Kip1, p53, p16INK4a, and p19ARF, were detected in myocytes of young WT mice, and their expression increased with age. IGF-1 attenuated the levels of these proteins at all ages. Telomerase activity decreased in aging WT myocytes but increased in TG, paralleling the changes in Akt phosphorylation. Reduction in nuclear phospho-Akt and telomerase resulted in telomere shortening and uncapping in WT myocytes. Senescence and death of CSCs increased with age in WT impairing the growth and turnover of cells in the heart. DNA damage and myocyte death exceeded cell formation in old WT, leading to a decreased number of myocytes and heart failure. This did not occur in TG in which CSC-mediated myocyte regeneration compensated for the extent of cell death preventing ventricular dysfunction. IGF-1 enhanced nuclear phospho-Akt and telomerase delaying cellular aging and death. The differential response of TG mice to chronological age may result from preservation of functional CSCs undergoing myocyte commitment. In conclusion, senescence of CSCs and myocytes conditions the development of an aging myopathy.

Necessity for lifelong follow-up of patients with familial paraganglioma syndrome: A case report.

BACKGROUND: Patients with established familial paraganglioma (PGL) syndrome may have multiple metachronous lesions. This article illustrates, via imaging and findings, the need for lifetime follow-up of patients with familial PGL syndromes. METHODS: Patients' medical charts and radiological images were reviewed in a retrospective analysis. RESULTS: Over the course of 18 years, this patient developed 2 simultaneous carotid PGLs, a cardiac PGL, and a biochemically active interaortocaval PGL. CONCLUSION: PGLs do not necessarily occur simultaneously in patients with familial PGL syndrome. Lifelong observation is needed to detect these lesions before they become large and symptomatic. Lack of biochemical activity is not a predictor of future lesions being inactive. Cardiac PGLs are rare and require resection.

Open pulmonary embolectomy for treatment of major pulmonary embolism.

BACKGROUND: Inadequate data exist regarding the management of acute major pulmonary embolism. Various modalities that are used, including thrombolytics and embolectomy, have not been shown to conclusively improve mortality when compared to heparin. In the past, open pulmonary embolectomy was reserved for patients with severe hemodynamic instability because of its high mortality rate. Our objective was to analyze our experience with early embolectomy as an alternative for the treatment of major pulmonary embolism. METHODS: A retrospective review of charts of all patients undergoing pulmonary embolectomy at our institution over the last two years was performed. Patients were followed until their discharge from hospital. RESULTS: There were 13 patients (7 women and 6 men). Four had massive and 9 had submassive pulmonary embolism. There was one mortality. Postoperative echocardiography showed no evidence of pulmonary hypertension in 7. CONCLUSIONS: Open pulmonary embolectomy can be performed in patients with major pulmonary embolism with minimal mortality and morbidity. It may prevent the development of chronic thromboembolic pulmonary hypertension and should be a part of the algorithm in the treatment of major pulmonary embolism.

Simultaneous use of bilateral subthalamic nucleus stimulators and an implantable cardiac defibrillator. Case report.

Bilateral electrical stimulation of the subthalamic nucleus is being used with increasing frequency as a treatment for severe Parkinson disease (PD). Implantable cardiac defibrillators improve survival in certain high-risk patients with coronary artery disease and ventricular arrhythmias. Because of concern about possible interaction between these devices, deep brain stimulation (DBS) systems are routinely disconnected before defibrillators are implanted in patients with PD and arrhythmia. The authors report on a patient with bilateral subthalamic stimulators who underwent successful placement of an implantable defibrillator. Testing of the devices over a wide range of settings revealed no interaction. The patient subsequently underwent multiple episodes of cardioversion when the ventricular lead became dislodged. There was no evidence of adverse neurological effects, and interrogation of the DBS devices after cardioversion revealed no changes in stimulus parameters. The outcome in this case indicates that DBS systems may be safely retained in selected patients who require implantable cardiac defibrillators.

The effect of pulmonary circulation hemodynamics on right ventricular unloading via the bidirectional Glenn shunt: implications for congenitally corrected transposition repair.

The bidirectional Glenn shunt has been successfully applied as an adjunct to ventricular septal defect closure and pulmonary valvulotomy to treat congenitally corrected transposition of the great arteries (ccTGA). The purpose of this study was to examine the volume and pressure unloading effects of the bidirectional Glenn shunt on the hypertrophied pulmonary ventricle in a canine model of ccTGA. Five beagles underwent survival surgery to band the pulmonary artery. Three months later, a polytetrafluoroethylene graft was anastomosed to the superior vena cava and right pulmonary artery. The graft or superior vena cava was clamped to create the normal or bidirectional Glenn circulation, and hemodynamic data were recorded. The bidirectional Glenn shunt significantly reduced right ventricular volume loading and stroke work. Dogs with normal pre-bidirectional Glenn cardiac outputs had greatly reduced right ventricular volumes and pressures with the bidirectional Glenn shunt. Dogs with pre-bidirectional Glenn right ventricular dysfunction had moderate volume but no pressure decreases with the bidirectional Glenn shunt owing to improved left ventricular output. In these dogs it is likely that the decreased level of pressure and volume unloading is because of a concomitant improvement in left ventricular output post-bidirectional Glenn shunt placement. The bidirectional Glenn shunt is effective at unloading the right ventricle in a canine model of ccTGA.

Evolution of operative techniques and perfusion strategies for minimally invasive mitral valve repair.

OBJECTIVE: Perfusion strategies and operative techniques for minimally invasive mitral valve repair have evolved over time. During the past decade, our institution's approach has progressed from a port access platform with femoral perfusion to predominantly a central aortic cannulation through a right anterior minithoracotomy incision. We analyzed this institutional experience to evaluate the impact of approach on patient outcomes. METHODS: Between 1995 and 2007, 1282 patients (mean age, 59.3 years; range, 18-99 years) underwent first-time, isolated mitral valve repair using a minimally invasive technique. Patient demographics included peripheral vascular disease (3.2%), chronic obstructive pulmonary disease (8.3%), atherosclerotic aorta (6.5%), cerebrovascular disease (4.3%), and ejection fraction less than 30% (4.3%). Retrograde perfusion was performed in 394 (30.7%) of all patients and endoaortic balloon occlusion in 373 (29.1%); the operative technique was a right anterior minithoracotomy in 1264 (98.6%) and left posterior minithoracotomy in 18 (1.4%). The etiology of mitral disease was degenerative in 73.2%, functional in 20.6%, and rheumatic in 2.4%. Data were collected prospectively using the New York State Cardiac Surgery Report System and a customized minimally invasive surgery data form. Logistic analysis was used to evaluate risk factors and outcomes; operative experience was divided into tertiles. RESULTS: Overall hospital mortality was 2.0% (25/1282). Mortality was 1.1% (10/939) for patients with degenerative etiology and 0.4% (3/693) for patients younger than 70 years of age with degenerative valve disease. Risk factors for death were advanced age (P = .007), functional etiology (P = .010; odds ratio [OR] = 3.3), chronic obstructive pulmonary disease (P = .013; OR = 3.4), peripheral vascular disease (P = .014; OR = 4.2), and atherosclerotic aorta (P = .03; OR = 2.8). Logistic risk factors for neurologic events were advanced age (P = .02), retrograde perfusion (P = .001; OR = 3.8), and emergency procedure (P = .01; OR = 66.6). Interaction modeling revealed that the only significant risk factor for neurologic event was the use of retrograde perfusion in high-risk patients with aortic disease (P = .04; OR = 8.5). Analysis of successive tertiles during this 12-year experience revealed a significant decrease in the use of retrograde arterial perfusion (89.6%, 10.4%, and 0.0%; P < .001) and endoaortic balloon occlusion (89.3%, 10.7%, and 0%; P < .001). The overall frequency of postoperative neurologic events was 2.3% (30/1282) and decreased from 4.7% in the first tertile to 1.2% in the second and third tertiles (P < .001). CONCLUSIONS: Central aortic cannulation through a right anterior minithoracotomy for mitral valve repair allows excellent outcomes in patients with a broad spectrum of comorbidities and has become our preferred approach for most patients undergoing mitral valve repair. Retrograde arterial perfusion is associated with an increased risk of stroke in patients with severe peripheral vascular disease and should be reserved for select patients without significant atherosclerosis.

Minimally invasive valve surgery with antegrade perfusion strategy is not associated with increased neurologic complications.

BACKGROUND: A Society of Thoracic Surgeons' publication recently associated "minimally invasive" approaches with increased neurologic complications; this proposed association was questionable due to imprecise definitions. To critically reevaluate this issue, we reviewed a large minimally invasive valve experience with robust definitions. METHODS: From November 1995 to January 2007, 3,180 isolated, non-reoperative valve operations were performed; 1,452 (45.7%) were aortic replacements and 1,728 (54.3%) were mitral valve procedures. Surgical approach was standard sternotomy (28%) or minimally invasive technique (72%). Antegrade arterial perfusion was used in 2,646 (83.2%) patients and retrograde perfusion in 534 (16.8%). Aortic clamping was direct in 83.4%, with endoclamp in 16.4% and no clamp in 0.2%. Patients were prospectively followed in a proprietary database and the New York State Cardiac Surgery Reporting System (mandatory, government audited). A neurologic event was defined as a permanent deficit, a transient deficit greater than 24 hours, or a new lesion on cerebral imaging. RESULTS: Hospital mortality for aortic valve replacement was 4.0% (sternotomy [5.1%] versus minimally invasive [3.4%] p = 0.13); for mitral procedures it was 2.4% (sternotomy [4.8%] versus minimally invasive [1.8%] p = 0.001). Multivariate analysis revealed that age, female gender, renal disease, ejection fraction less than 0.30, chronic obstructive pulmonary disease, and emergent operation were risk factors for mortality. Stroke occurred in 71 patients (2.2%) (sternotomy [2.1%] versus minimally invasive [2.3%] p = 0.82). Multivariate analysis of neurologic events revealed that cerebrovascular disease, emergency procedure, no-clamp, and retrograde perfusion were risk factors. In patients 50 years old or younger (n = 662), retrograde perfusion had no significant impact on neurologic events (1.6% vs 1.1%, p = 0.57). CONCLUSIONS: A minimally invasive approach with antegrade perfusion does not result in increased neurologic complications. Retrograde perfusion, however, is associated with increased neurologic risk in older patients.

Human cardiac stem cells.

The identification of cardiac progenitor cells in mammals raises the possibility that the human heart contains a population of stem cells capable of generating cardiomyocytes and coronary vessels. The characterization of human cardiac stem cells (hCSCs) would have important clinical implications for the management of the failing heart. We have established the conditions for the isolation and expansion of c-kit-positive hCSCs from small samples of myocardium. Additionally, we have tested whether these cells have the ability to form functionally competent human myocardium after infarction in immunocompromised animals. Here, we report the identification in vitro of a class of human c-kit-positive cardiac cells that possess the fundamental properties of stem cells: they are self-renewing, clonogenic, and multipotent. hCSCs differentiate predominantly into cardiomyocytes and, to a lesser extent, into smooth muscle cells and endothelial cells. When locally injected in the infarcted myocardium of immunodeficient mice and immunosuppressed rats, hCSCs generate a chimeric heart, which contains human myocardium composed of myocytes, coronary resistance arterioles, and capillaries. The human myocardium is structurally and functionally integrated with the rodent myocardium and contributes to the performance of the infarcted heart. Differentiated human cardiac cells possess only one set of human sex chromosomes excluding cell fusion. The lack of cell fusion was confirmed by the Cre-lox strategy. Thus, hCSCs can be isolated and expanded in vitro for subsequent autologous regeneration of dead myocardium in patients affected by heart failure of ischemic and nonischemic origin.

Role of prostaglandins in mediating differences in human internal mammary and radial artery relaxation elicited by hypoxia.

The effects of hypoxia-reoxygenation on internal mammary (IMA) and radial (RA) arteries used for coronary artery bypass grafting (CABG) were examined to identify mechanisms regulating contractile function and differences that could contribute to vasospasm. Isolated endothelium-intact IMA and RA rings precontracted with KCl (30 mM) rapidly dilated to hypoxia (95% N(2)/5% CO(2)) with a greater relaxation in RA than IMA. Inhibitors of cyclooxygenase (10 microM indomethacin) and the thromboxane A(2) (TxA)(2) receptor [1 microM [1S-[1alpha,2alpha(Z),3alpha,4alpha]]-7-[3-[2-(phenylamino)carbonyl]hydrazine]methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid (SQ-29548)] potentiated the relaxation to hypoxia in IMA, but not RA, a response associated with increases in TxA(2). Relaxation of IMA and RA to hypoxia appears to involve a calcium-reuptake mechanism inhibited by cyclopiazonic acid (0.2 mM), and it was not attenuated by a blocker of potassium channels (10 mM TEA). The recovery of force generation of IMA, but not RA, upon reoxygenation after 30 min of hypoxia was significantly reduced in the initial phase of reoxygenation by indomethacin and SQ-29548 and by endothelin receptor blocker BQ-123 [cyclo(l-Leu-d-Trp-d-Asp-l-Pro-d-Val)]. Thus, hypoxia relaxes IMA and RA by a prostaglandin-independent mechanism potentially involving enhanced intracellular calcium reuptake. The prostaglandin-mediated alterations of responses to hypoxia-reoxygenation seen in IMA, but not in RA, may predispose IMA to vasospasm-related complications of CABG.