Staged Hybrid Repair of an Intrathoracic Subclavian Artery Aneurysm Associated with a Long Segment Dissection.

Intrathoracic subclavian artery aneurysms (ISAAs) are infrequently seen in clinical practice. We report the repair of a left ISAA associated with a long segment dissection from the ostia extending to the axillary artery. A hybrid approach was used. Carotid-to-axillary bypass using a reversed greater saphenous vein was first performed, followed by coverage of the origin of the subclavian artery using a thoracic stent graft. Finally, percutaneous access of the radial artery with coil embolization was performed to successfully thrombose the ISAA.

Angiotensin-converting enzyme inhibition or mineralocorticoid receptor blockade do not affect prevalence of atrial fibrillation in patients undergoing cardiac surgery.

OBJECTIVE: This study tested the hypothesis that interruption of the renin-angiotensin system with either an angiotensin-converting enzyme inhibitor or a mineralocorticoid receptor antagonist will decrease the prevalence of atrial fibrillation after cardiac surgery. DESIGN: Randomized double-blind placebo-controlled study. SETTING: University-affiliated hospitals. PATIENTS: Four hundred forty-five adult patients in normal sinus rhythm undergoing elective cardiac surgery. INTERVENTIONS: One week to 4 days prior to surgery, patients were randomized to treatment with placebo, ramipril (2.5 mg the first 3 days followed by 5 mg/day, with the dose reduced to 2.5 mg/day on the first postoperative day only), or spironolactone (25 mg/day). MEASUREMENTS: The primary endpoint was the occurrence of electrocardiographically confirmed postoperative atrial fibrillation. Secondary endpoints included acute renal failure, hyperkalemia, the prevalence of hypotension, length of hospital stay, stroke, and death. MAIN RESULTS: The prevalence of atrial fibrillation was 27.2% in the placebo group, 27.8% in the ramipril group, and 25.9% in the spironolactone group (p=.95). Patients in the ramipril (0.7%) or spironolactone (0.7%) group were less likely to develop acute renal failure than those randomized to placebo (5.4%, p=.006). Patients in the placebo group tended to be hospitalized longer than those in the ramipril or spironolactone group (6.8±8.2 days vs. 5.7±3.2 days and 5.8±3.4 days, respectively, p=.08 for the comparison of placebo vs. the active treatment groups using log-rank test). Compared with patients in the placebo group, patients in the spironolactone group were extubated sooner after surgery (576.4±761.5 mins vs. 1091.3±3067.3 mins, p=.04). CONCLUSIONS: Neither angiotensin-converting enzyme inhibition nor mineralocorticoid receptor blockade decreased the primary outcome of postoperative atrial fibrillation. Treatment with an angiotensin-converting enzyme inhibitor or mineralocorticoid receptor antagonist was associated with decreased acute renal failure. Spironolactone use was also associated with a shorter duration of mechanical ventilation after surgery.

Adenosine receptor-mediated adhesion of endothelial progenitors to cardiac microvascular endothelial cells.

Intracoronary delivery of endothelial progenitor cells (EPCs) is an emerging concept for the treatment of cardiovascular disease. Enhancement of EPC adhesion to vascular endothelium could improve cell retention within targeted organs. Because extracellular adenosine is elevated at sites of ischemia and stimulates neovascularization, we examined the potential role of adenosine in augmenting EPC retention to cardiac microvascular endothelium. Stimulation of adenosine receptors in murine embryonic EPCs (eEPCs) and cardiac endothelial cells (cECs) rapidly, within minutes, increased eEPC adhesion to cECs under static and flow conditions. Similarly, adhesion of human adult culture-expanded EPCs to human cECs was increased by stimulation of adenosine receptors. Furthermore, adenosine increased eEPC retention in isolated mouse hearts perfused with eEPCs. We determined that eEPCs and cECs preferentially express functional A1 and A2B adenosine receptor subtypes, respectively, and that both subtypes are involved in the regulation of eEPC adhesion to cECs. We documented that the interaction between P-selectin and its ligand (P-selectin glycoprotein ligand-1) plays a role in adenosine-dependent eEPC adhesion to cECs and that stimulation of adenosine receptors in cECs induces rapid cell surface expression of P-selectin. Our results suggest a role for adenosine in vasculogenesis and its potential use to stimulate engraftment in cell-based therapies.

Minimally invasive right lateral thoracotomy without aortic cross-clamping: an attractive alternative to repeat sternotomy for reoperative mitral valve surgery.

BACKGROUND AND AIM OF THE STUDY: The study aim was to determine the safety and benefits of minimally invasive mitral valve surgery without aortic cross-clamping for mitral valve surgery after previous cardiac surgery. METHODS: Between January 2006 and August 2008, a total of 90 consecutive patients (38 females, 52 males; mean age 66 +/- 9 years) underwent minimally invasive mitral valve surgery after having undergone previous cardiac surgery. Of these patients, 80 (89%) underwent mitral valve replacement and 10 (11%) mitral valve repair utilizing a small (5 cm) right lateral thoracotomy along the 4th or 5th intercostal space under fibrillatory arrest (mean temperature 28 +/- 2 degrees C). The predicted mortality, calculated using the Society of Thoracic Surgeons (STS) algorithm, was compared to the observed mortality. RESULTS: The mean ejection fraction was 45 +/- 13%, mean NYHA class 3 +/- 1, while 66 patients (73%) had previous coronary artery bypass grafting and 37 (41%) had previous valve surgery. Twenty-six patients (29%) underwent non-elective surgery. Cardiopulmonary bypass was instituted through axillary (n = 19), femoral (n = 70) or direct use aortic (n = 1) cannulation. Operative mortality was 2% (2/90), lower than the STS-predicted mortality of 7%. Three patients (3%) developed acute renal failure postoperatively, one patient (1%) required new-onset hemodialysis, and one (1%) developed postoperative stroke. No patients developed postoperative myocardial infarction. The mean postoperative packed red blood cell transfusion requirement at 48 h was 2 +/- 3 units. CONCLUSION: Minimally invasive right thoracotomy without aortic cross-clamping is an excellent alternative to conventional redo-sternotomy for reoperative mitral valve surgery. The present study confirmed that this technique is safe and effective in reducing operative mortality in high-risk patients undergoing reoperative cardiac surgery.

Recurrent atrial myxoma: resection for Carney complex through a minimally invasive approach.

Carney's complex is an autosomal dominant syndrome characterized by recurrent atrial myxomas with concurrent endocrinopathies and characteristic dermatologic features. We present the case of a woman who presented with a recurrent atrial myxoma after two previous resections for myxomas through median sternotomies. As a consequence, we utilized a minimally invasive right thoracotomy approach. We discuss the clinical and pathologic features of Carney complex and the importance of identifying individuals and families with this condition for treatment and counseling.

Milrinone use is associated with postoperative atrial fibrillation after cardiac surgery.

BACKGROUND: Postoperative atrial fibrillation (AF), a frequent complication after cardiac surgery, causes morbidity and prolongs hospitalization. Inotropic drugs are commonly used perioperatively to support ventricular function. This study tested the hypothesis that the use of inotropic drugs is associated with postoperative AF. METHODS AND RESULTS: We evaluated perioperative risk factors in 232 patients who underwent elective cardiac surgery. All patients were in sinus rhythm at surgery. Sixty-seven patients (28.9%) developed AF a mean of 2.9+/-2.1 days after surgery. Patients who developed AF stayed in the hospital longer (P<0.001) and were more likely to die (P=0.02). Milrinone use was associated with an increased risk of postoperative AF (58.2% versus 26.1% in nonusers; P<0.001). Older age (63.4+/-10.7 versus 56.7+/-12.3 years; P<0.001), hypertension (P=0.04), lower preoperative ejection fraction (P=0.03), mitral valve surgery (P=0.02), right ventricular dysfunction (P=0.03), and higher mean pulmonary artery pressure (27.1+/-9.3 versus 21.8+/-7.5 mm Hg; P=0.001) also were associated with postoperative AF. In multivariable logistic regression, age (P<0.001), ejection fraction (P=0.02), and milrinone use (odds ratio, 4.86; 95% confidence interval, 2.31 to 10.25; P<0.001) independently predicted postoperative AF. When only data from patients with pulmonary artery catheters were analyzed and pulmonary artery pressure was included in the model, age, milrinone use (odds ratio, 4.45; 95% confidence interval, 2.01 to 9.84; P<0.001), and higher pulmonary artery pressure (P=0.02) were associated with an increased risk of postoperative AF. Adding other potential confounders or stratifying analysis by mitral valve surgery did not change the association of milrinone use with postoperative AF. CONCLUSIONS: Milrinone use is an independent risk factor for postoperative AF after elective cardiac surgery.

Idiopathic mitral valve disease in a patient presenting with Axenfeld-Rieger syndrome.

A 33-year-old, previously healthy male presented with respiratory distress and underwent intubation. A physical examination revealed a holosystolic murmur and pupillary abnormalities. Echocardiography revealed a flail anterior mitral valve leaflet with ruptured chordae and severe mitral regurgitation. The patient underwent urgent mitral valve replacement and tolerated the procedure well. The mitral valve leaflet was myxomatous and calcified -- an unusual find in such a patient. An ophthalmology consultation was obtained and the patient diagnosed with Axenfeld-Rieger syndrome, a disorder of the anterior ocular chamber that has been associated with cardiac malformations. The present case report adds to the body of literature which suggests a correlation between Axenfeld-Rieger syndrome and valvular abnormalities. Hence, it is believed prudent that patients with Axenfeld-Rieger syndrome should undergo echocardiographic screenings for valvular abnormalities.

Plasminogen activator inhibitor-1 as a predictor of postoperative atrial fibrillation after cardiopulmonary bypass.

BACKGROUND: Postoperative atrial fibrillation (AF), leading to significant morbidity and prolongation of hospital stay, complicates 20% to 40% of surgical procedures requiring cardiopulmonary bypass (CPB). This study tests the hypothesis that biomarkers predict the development of postoperative AF. METHODS AND RESULTS: We enrolled 253 adult patients undergoing elective cardiac surgery requiring CPB and who were in sinus rhythm at the time of surgery. Blood samples were obtained for measurement of 21 biomarkers immediately after separation from CPB and administration of protamine. Patients who developed postoperative AF (67 subjects, 26.5%) were significantly older (P<0.001), more likely to have a remote history of AF (P<0.001), and tended to be more likely to have had valve surgery (P=0.082). Plasminogen activator inhibitor-1 (P=0.014), interleukin (IL)-6 (P=0.019), and N-terminal prohormone brain natriuretic peptide (P=0.028) concentrations were significantly higher in the blood of patients who developed postoperative AF. Logistic regression identified age (P<0.001), remote history of AF (P=0.001), and postoperative PAI-1 (P=0.036) as independent predictors of postoperative AF. When preoperative PAI-1 antigen concentrations were included in the model age (P<0.001), remote history of AF (P<0.001) and preoperative PAI-1 (P=0.015) were identified as independent predictors of postoperative AF. The Chi-squared Automatic Interaction Detection (CHAID) model indicated that age was the primary determinant for the development of postoperative AF (17% in age < or = 67.3 years versus 49% in age > 67.3 years). Within younger patients (age < or = 67.3 years) without remote history of AF, postoperative PAI-1 antigen concentration next determined risk of AF (13% if PAI-1 < or = 28.5 ng/mL versus 46% if PAI-1 > 28.5 ng/mL). CONCLUSION: An elevated preoperative or postoperative PAI-1 antigen concentration is an independent predictor for development of AF after CPB. Studies are needed to determine whether drugs that reduce PAI-1 concentrations can also reduce the risk of postoperative AF.

Argatroban in short-term percutaneous ventricular assist subsequent to heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia paradoxically is a transient pro-thrombotic disorder triggered by heparin exposure. If not treated appropriately, it can be life threatening because of its related thromboembolic complications. In particular, it presents a unique challenge in patients needing extracorporeal life support, because anticoagulation is essential for safe management. This case report describes the safe, efficacious use of Argatroban during short-term support of a patient with a percutaneously inserted left ventricular assist TandemHeart device.

Oxygenation failure during cardiopulmonary bypass prompts new safety algorithm and training initiative.

Developing new strategies to improve patient safety and risk reduction is fundamental to hospital and patient success. Currently, there is a tendency in hospital safety management to focus solely on human error rather than organizational and educational causes that contribute to medical accidents. Although health care providers are the primary safety systems in medical facilities, there must be a more global, perhaps automated, approach using modern technology to prevent or reduce medical mishaps. Herein, we present an oxygenation failure with root cause analysis that prompted a new oxygenation safety algorithm and multi-service training initiative.

Minimally invasive mitral valve repair suggests earlier operations for mitral valve disease.

OBJECTIVE: We began minimally invasive mitral valve surgery in August, 1996, to reduce hospital costs, to improve patient recovery, cosmetic appearance, and to decrease trauma, yet maintain the same quality of surgery. To validate this approach we reviewed our entire experience through May 2002. METHODS: From August 1996 to May 2002, we performed 413 minimally invasive mitral valve operations including 51 mitral valve replacements and 362 mitral valve repairs. Excluding 4 robotically assisted repairs, we evaluated 358 patients, using the mitral valve repairs as the basis for this retrospective survey. These operations were performed through a 6- to 8-cm minimally invasive incision, beginning with parasternal and, most recently, lower ministernotomy (181 patients). The mitral valve reparative techniques include repair of 94 prolapsed anterior leaflets, posterior leaflet resection, leaflet advancement, commissuroplasty, Polytetrafluoroethylene (PTFE; Gore-Tex, W. L. Gore & Associates, Inc, Flagstaff, Ariz) chordal placement, and ring annuloplasty. Cannulation sites varied but primarily utilized a miniaturized system of 24F catheters in both the inferior and superior venae cavae with assisted venous suction. The Cosgrove ring was used in 95% of the patients undergoing this procedure. RESULTS: The operative mortality was 0/358. Perioperative morbidity included a 26% incidence of new atrial fibrillation, 2% incidence of pacemaker implantation, 0.5% incidence of deep sternal wound infection, and 1.9% incidence of stroke after an operation. There were 10 arterial and 3 venous complications. The mean length of stay was 6 days and 208 patients stayed < or =5 days. Only 25% of the patients underwent homologous blood transfusion. The mean follow-up was 36 months with 1.4% lost to follow-up. There were 12 late deaths and a survival at 5 years of 95%. There were 21 valves requiring reoperation for structural valve failure of 5.8%. The probability of freedom from reoperation at 5 years was 92%. CONCLUSION: This study documents the safety of minimally invasive mitral valve repair surgery in 358 patients. It also documents a low incidence of homologous blood use, requirement for post-hospital rehabilitation, and general morbidity.

Quantitative Imaging of Preamyloid Oligomers, a Novel Structural Abnormality, in Human Atrial Samples.

Abnormalities in atrial myocardium increase the likelihood of arrhythmias, including atrial fibrillation (AF). The deposition of misfolded protein, or amyloidosis, plays an important role in the pathophysiology of many diseases, including human cardiomyopathies. We have shown that genes implicated in amyloidosis are activated in a cellular model of AF, with the development of preamyloid oligomers (PAOs). PAOs are intermediates in the formation of amyloid fibrils, and they are now recognized to be the cytotoxic species during amyloidosis. To investigate the presence of PAOs in human atrium, we developed a microscopic imaging-based protocol to enable robust and reproducible quantitative analysis of PAO burden in atrial samples harvested at the time of elective cardiac surgery. Using PAO- and myocardial-specific antibodies, we found that PAO distribution was typically heterogeneous within a myocardial sample. Rigorous imaging and analysis protocols were developed to quantify the relative area of myocardium containing PAOs, termed the Green/Red ratio (G/R), for a given sample. Using these methods, reproducible G/R values were obtained when different sections of a sample were independently processed, imaged, and analyzed by different investigators. This robust technique will enable studies to investigate the role of this novel structural abnormality in the pathophysiology of and arrhythmia generation in human atrial tissue.

Hypertension is associated with preamyloid oligomers in human atrium: a missing link in atrial pathophysiology?

BACKGROUND: Increasing evidence indicates that proteotoxicity plays a pathophysiologic role in experimental and human cardiomyopathy. In organ-specific amyloidoses, soluble protein oligomers are the primary cytotoxic species in the process of protein aggregation. While isolated atrial amyloidosis can develop with aging, the presence of preamyloid oligomers (PAOs) in atrial tissue has not been previously investigated. METHODS AND RESULTS: Atrial samples were collected during elective cardiac surgery in patients without a history of atrial arrhythmias, congestive heart failure, cardiomyopathy, or amyloidosis. Immunohistochemistry was performed for PAOs using a conformation-specific antibody, as well as for candidate proteins identified previously in isolated atrial amyloidosis. Using a myocardium-specific marker, the fraction of myocardium colocalizing with PAOs (PAO burden) was quantified (green/red ratio). Atrial samples were obtained from 92 patients, with a mean age of 61.7±13.8 years. Most patients (62%) were male, 23% had diabetes, 72% had hypertension, and 42% had coronary artery disease. A majority (n=62) underwent aortic valve replacement, with fewer undergoing coronary artery bypass grafting (n=34) or mitral valve replacement/repair (n=24). Immunostaining detected intracellular PAOs in a majority of atrial samples, with a heterogeneous distribution throughout the myocardium. Mean green/red ratio value for the samples was 0.11±0.1 (range 0.03 to 0.77), with a value ≥0.05 in 74 patients. Atrial natriuretic peptide colocalized with PAOs in myocardium, whereas transthyretin was located in the interstitium. Adjusting for multiple covariates, PAO burden was independently associated with the presence of hypertension. CONCLUSION: PAOs are frequently detected in human atrium, where their presence is associated with clinical hypertension.

Improved midterm outcomes for type A (central) pulmonary emboli treated surgically.

OBJECTIVES: We propose a simplified anatomic classification for pulmonary emboli that algorithmically differentiates those who might be best treated with surgical pulmonary embolectomy (type A) from those best treated medically (type B). We hypothesized that patients with type A pulmonary emboli treated with immediate surgical embolectomy demonstrate superior long-term survival compared with patients with type A pulmonary emboli treated medically. METHODS: Patients admitted between 2002 and 2008 with a diagnosis of pulmonary emboli made based on computed tomographic angiographic imaging (n = 779) were analyzed. Computed tomographic angiographic images were reviewed in a blind fashion, and anatomic classification of emboli was made. Patients with central thrombus, defined by location medial to the lateral mediastinal boundaries (ie, involving the main, primary, or both branch pulmonary arteries), were classified as having type A pulmonary emboli (n = 107), whereas those with peripheral pulmonary emboli located beyond these boundaries were classified as having type B pulmonary emboli (n = 672). Four patients with type A pulmonary emboli treated with catheter embolectomy were excluded from the analysis. RESULTS: Of the 103 patients with type A pulmonary emboli, 15 (14%) were treated with immediate surgical pulmonary embolectomy, and 88 (85%) were treated medically. Patients with type A pulmonary emboli treated surgically had similar 30-day mortality compared with those treated medically (13% vs 17%, P = .532). At a mean of 24 ± 18 months' follow-up (range, 1-82 months), survival at 1, 3, and 5 years for patients with type A pulmonary emboli treated surgically was significantly better than that in the patients with type A pulmonary emboli treated medically (P = .0001). CONCLUSIONS: For patients with type A pulmonary emboli, immediate surgical intervention appears to offer superior midterm survival compared with medical treatment alone. Although the medical and surgical groups were substantially different and the differences might have affected survival, this simplified classification for pulmonary emboli might help direct optimal treatment strategies.

Results of completion arteriography after minimally invasive off-pump coronary artery bypass.

BACKGROUND: The benefits of a minimally invasive approach to off-pump coronary artery bypass remain controversial. The value of completion arteriography in validating this technique has not been investigated. METHODS: From April 2007 to October 2009, fifty-six patients underwent isolated minimally invasive coronary artery bypass grafting through a left thoracotomy without cardiopulmonary bypass. Forty-three of these patients underwent completion arteriography. RESULTS: Sixty-five grafts were performed in these 56 patients, (average, 1.2 grafts per patient; range, 1 to 3). Forty-eight grafts were studied in the 43 patients undergoing completion arteriography. There were 4 findings on arteriogram leading to further immediate intervention (8.3%). These included 3 grafts with anastomotic stenoses or spasm requiring stent placement, and 1 patient who had limited dissection in the left internal mammary artery graft and underwent placement of an additional vein graft. These findings were independent of electrocardiographic changes or hemodynamic instability. The remainder of the studies showed no significant abnormalities. There were no deaths. One patient who did not have a completion arteriogram suffered a postoperative myocardial infarction requiring stent placement for anastomotic stenosis. Patients were discharged home an average of 6.8 days postoperatively. There were no instances of renal dysfunction postoperatively attributable to catheterization. CONCLUSIONS: Minimally invasive coronary artery bypass is safe and effective. Findings of completion arteriography occasionally reveal previously under-recognized findings that, if corrected in a timely fashion, could potentially impact graft patency and clinical outcomes. Our experience validates this minimally invasive technique.

Routine intraoperative completion angiography after coronary artery bypass grafting and 1-stop hybrid revascularization results from a fully integrated hybrid catheterization laboratory/operating room.

OBJECTIVES: This study sought to report our experience with a routine completion angiogram after coronary artery bypass surgery (CABG) and simultaneous (1-stop) percutaneous coronary intervention (PCI) at the time of CABG performed in the hybrid catheterization laboratory/operating room. BACKGROUND: The value of a routine completion angiogram after CABG and 1-stop hybrid CABG/PCI remains unresolved. METHODS: Between April 2005 and July 2007, 366 consecutive patients underwent CABG surgery, with (n = 112) or without (n = 254) concomitant 1-stop PCI (hybrid), all with completion angiography before chest closure. Among the 112 1-stop hybrid CABG/PCI patients, 67 (60%) underwent a planned hybrid procedure based on pre-operative assessment, whereas 45 (40%) underwent open-chest PCI (unplanned hybrid) based on intraoperative findings. RESULTS: Among the 796 CABG grafts (345 left internal mammary artery, 12 right internal mammary artery/radial, and 439 veins), 97 (12%) angiographic defects were identified. Defects were repaired with either a minor adjustment of the graft (n = 22, 2.8%), with intraoperative open-chest PCI (unplanned hybrid, n = 48, 6%) or with traditional surgical revision (n = 27, 3.4%). Hybrid patients had clinical outcomes similar to standard CABG patients. CONCLUSIONS: Routine completion angiography detected 12% of grafts with important angiographic defects. One-stop hybrid coronary revascularization is reasonable, safe, and feasible. Combining the tools of the catheterization laboratory and operating room greatly enhances the options available to the surgeon and cardiologist for patients with complex coronary artery disease.

Safety of minimally invasive mitral valve surgery without aortic cross-clamp.

BACKGROUND: We developed a technique for open heart surgery through a small (5 cm) right-anterolateral thoracotomy without aortic cross-clamp. METHODS: One hundred and ninety-five consecutive patients (103 male and 92 female), age 69 +/- 8 years, underwent surgery between January 2006 and July 2007. Mean preoperative New York Heart Association function class was 2.2 +/- 0.7. Thirty-five patients (18%) had an ejection fraction 0.35 or less. Cardiopulmonary bypass was instituted through femoral (176 of 195, 90%), axillary (18 of 195, 9%), or direct aortic (1 of 195, 0.5%) cannulation. Under cold fibrillatory arrest (mean temperature 28.2 degrees C) without aortic cross-clamp, mitral valve repair (72 of 195, 37%), mitral valve replacement (117 of 195, 60%), or other (6 of 195, 3%) procedures were performed. Concomitant procedures included maze (45 of 195, 23%), patent foramen ovale closure (42 of 195, 22%) and tricuspid valve repair (16 of 195, 8%), or replacement (4 of 195, 2%). RESULTS: Thirty-day mortality was 3% (6 of 195). Duration of fibrillatory arrest, cardiopulmonary bypass, and "skin to skin" surgery were 88 +/- 32, 118 +/- 52, and 280 +/- 78 minutes, respectively. Ten patients (5%) underwent reexploration for bleeding and 44% did not receive any blood transfusions. Six patients (3%) sustained a postoperative stroke, eight (4%) developed low cardiac output syndrome, and two (1%) developed renal failure requiring hemodialysis. Mean length of hospital stay was 7 +/- 4.8 days. CONCLUSIONS: This simplified technique of minimally invasive open heart surgery is safe and easily reproducible. Fibrillatory arrest without aortic cross-clamping, with coronary perfusion against an intact aortic valve, does not increase the risk of stroke or low cardiac output. It may be particularly useful in higher risk patients in whom sternotomy with aortic clamping is less desirable.