Amram J. Cohen
Walter Reed Army Medical Center
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The Annals of Thoracic Surgery | 1991
Fred H. Edwards; Douglas A. Hale; Amram J. Cohen; LeNardo Thompson; A.Thomas Pezzella; Renu Virmani
To investigate the characteristics of primary cardiac valve tumors, we retrospectively analyzed our multiinstitutional experience from 1932 through 1990. We encountered 56 valvular tumors in 53 patients. The average age of these patients was 52 years (range, 2 to 88 years) and 79% (42/53) were male. Symptoms were present in 38% (20/53) and were neurological in 15% (8/53). Four patients experienced sudden death. Each of the four valves was affected with approximately equal frequency: 16 aortic, 15 mitral, 13 pulmonary, and 12 tricuspid. All but four tumors were benign. The most common histological type was papillary fibroelastoma (41), followed by myxomas (5), fibromas (4), sarcomas (2), hamartoma (1), hemangioma (1), histiocytoma (1), and undifferentiated (1). Average tumor size was 1.15 cm (range, 3 mm to 7 cm), and the average size of fibroelastomas was 8 mm (range, 3 to 15 mm). Mitral valve tumors were more likely than aortic valve tumors to produce serious neurological symptoms or sudden death (8/15 versus 3/16; p less than 0.05). Six patients underwent echocardiography, and results were positive in each. All 6 underwent uncomplicated valve repair or replacement. Compared with a series of 407 nonvalvular tumors, cardiac valve tumors are more likely to occur in male patients (p less than 0.001) and adults (p less than 0.001). Valve tumors are also more commonly benign (p less than 0.001) and asymptomatic (p less than 0.001). These tumors demonstrate somewhat less aggressive behavior compared with non-valvular tumors, but their distinct propensity to produce serious clinical sequelae argues in favor of surgical resection for all cardiac valve tumors.
The Journal of Thoracic and Cardiovascular Surgery | 1999
Amram J. Cohen; Judith Lockman; Mordechai Lorberboym; Othman Bder; Nadav Cohena; Benjamin Medalion; Arie Schachner
OBJECTIVE This study prospectively evaluates the effect on sternal vascularity of harvesting the left internal thoracic artery. METHODS Twenty-four consecutive patients undergoing primary coronary artery bypass grafting were studied. One patients procedure was altered during the operation, and he was eliminated from the study. The patients were prospectively randomized to receive a skeletonized internal thoracic artery (group I, n = 11) or a pedicled internal thoracic artery (group II, n = 12) graft. Each patient underwent a preoperative technetium 99 methylene diphosphonate bone scan using single photon emission computed tomography. The ratio of the mean counts per pixel on the left side of the sternum was compared with the mean counts per pixel on the right side. Postoperatively, all patients had a second scan, and sternal uptake was compared with the preoperative uptake. RESULTS No significant differences in preoperative and operative variables were observed between the groups. A statistically significant reduction in blood flow to the left side of the sternum was shown postoperatively in group II compared with group I (0.61 +/- 0.11 vs 0.85 +/- 0.09; P <.001). Multivariable logistic regression analysis of preoperative and operative variables revealed only a pedicled left internal thoracic artery to be associated with a 20% or more reduction in left-to-right sternal activity ratio (odds ratio, 100; 70% confidence limits, 22-465; P =.002). CONCLUSION A pedicled left internal thoracic artery graft to the left anterior descending artery reduces blood flow to the left side of the sternum during the acute postoperative period. This does not occur when the left internal thoracic artery is skeletonized.
The Annals of Thoracic Surgery | 1991
Amram J. Cohen; LeNardo Thompson; Fred H. Edwards; Ronald F. Bellamy
A retrospective analysis was performed on 230 patients with primary cysts and tumors of the mediastinum seen at our institution from January 1944 to April 1989. We divided these patients into two groups. Group 1 was seen before 1970 and group 2 was seen from January 1970 to April 1989. There was a significant increase in the prevalence of malignancy in group 2 (47.2% versus 17.1%; p less than 0.0001) due to an increase in the number of lymphomas (22.6% versus 3.5%; p less than 0.001) and malignant neurogenic tumors (6.8% versus 1.1%; p = 0.0528). There was a significant increase in the number of malignant tumors in the anterior (59.5% versus 30.9%; p = 0.0022) and paravertebral (28.5% versus 2.8%; p = 0.0027) compartments in group 2. More patients with these tumors were symptomatic in group 2 (63.6% versus 5%; p = 0.0422). There was an increase of ancillary diagnostic studies performed to evaluate these tumors (76.0% versus 34.5%; p = 0.0422). Logistic regression analysis identified date of presentation (p less than 0.005), symptoms (p less than 0.01), size (p less than 0.005), and the anterior mediastinal compartment (p less than 0.005) as preoperative predictors of malignancy. The surgical approach to these tumors included more median sternotomy (30.1% versus 10.7%; p = 0.0008), anterior mediastinotomy, and cervical mediastinoscopy in group 2 (1.1% versus 17.5%; p = 0.0002). Long-term results support surgical resection in benign lesions and an aggressive multimodality approach to malignant lesions.
The Annals of Thoracic Surgery | 1992
Kenneth S. Azarow; Richard H. Pearl; Mark A. Hoffman; Robert P. Zurcher; Fred H. Edwards; Amram J. Cohen
The records of 21 patients who underwent operation for symptoms attributable to vascular ring were reviewed. The study covered 33 years, 1958 to 1991, and the mean follow-up was 6.8 years. The patients ranged from 7 days to 26 years old with a mean age of 2.9 years. Twenty patients were symptomatic. Symptoms were due to tracheal compression in 16 patients, esophageal compression in 2, and both causes in 2. During the first 30 years, chest roentgenography, barium swallow, and aortography constituted the diagnostic workup in the majority of the patients. During the last 3 years, magnetic resonance imaging replaced aortography. The surgical diagnosis included five variants of vascular ring. The surgical approach consisted of left thoracotomy in 19 patients and right thoracotomy in 2. These 2 had the diagnosis of right aortic arch with posterior left subclavian artery. In both instances, preoperative angiographic data determined the surgical approach. Barium swallow may be sufficient for the diagnosis of vascular ring; however, additional data are useful in determining the surgical approach. Magnetic resonance imaging can yield accurate data without subjecting the patient to the risks associated with angiography.
The Annals of Thoracic Surgery | 1990
Fred H. Edwards; Ronald F. Bellamy; J.Robert Burge; Amram J. Cohen; LeNardo Thompson; Michael J. Barry; Lawrence Weston
Abstract Previous reports of emergency coronary artery bypass grafting often included cues that were not true surgical emergencies, thereby creating inappropriately favorable results. To accurately investigate this important subgroup of patients, we analyzed our recent experience with truly emergent coronary artery bypass grafting. From January 1984 to January 1989, 117 patients underwent true emergency bypass grafting for acute refractory coronary artery ischemia. Clinical deterioration was associated with failure of percutaneous angioplasty in 37 patients and instability during diagnostic catheterization in 13 patients. Refractory ischemia developed in the remaining patients while on the ward or in the intensive care unit. All operations were performed within four hours of surgical consultation, most within one hour. Overall in-hospital operative mortality was 14.5% ( 17 / 117 ), and 76.5% of deaths ( 13 / 17 ) were due to cardiac-related causes. Major morbidity occurred in 35.9% ( 42 / 117 ). Univariate analysis isolated ejection fraction, extent of coronary artery disease, previous myocardial infarction, hypertension, need for inotropic support, use of an intraaortic balloon pump, and cardiopulmonary resuscitation as risk factors for operative mortality. Stepwise multivariate analysis confirmed that previous myocardial infarction, hypertension, cardiopulmonary resuscitation, and reoperation were independently significant risk factors. Age, sex, diabetes, left main disease, and peripheral vascular disease had no significant impact on the prognosis. The 4% operative mortality ( 2 / 50 ) for patients taken directly to the operating room from the catheterization suite was significantly lower than the 22.4% mortaiity ( 15 / 67 ) associated with emergerncies arising on the ward or intensive care unit ( p
The Annals of Thoracic Surgery | 1989
LeNardo Thompson; Amram J. Cohen; Fred H. Edwards; Michael J. Barry
A patient with coronary artery disease and idiopathic thrombocytopenia purpura underwent coronary artery bypass grafting without splenectomy. Our experience indicates that use of cardiopulmonary bypass in patients with idiopathic thrombocytopenic purpura does not invariably mandate splenectomy.
The Annals of Thoracic Surgery | 1991
Amram J. Cohen; David C. Cleveland; John D. Dyck; Dolores Poppe; Jeffrey F. Smallhorn; Robert M. Freedom; George A. Trusler; John G. Coles; C.A.Frederick Moes; Ivan M. Rebeyka; William G. Williams
One hundred twenty-four consecutive patients with univentricular heart undergoing the Fontan operation were reviewed. Patients with tricuspid atresia or biventricular heart with hypoplasia of one ventricle were excluded. Eighty-four patients had left ventricular morphology. Atrioventricular connection was double-inlet (n = 76), common (n = 29), absent left atrioventricular connection (n = 14), and absent right atrioventricular connection (n = 5). Actuarial survival was 77% (70% confidence limits, 73% to 81%) at 1 year, 66% (70% confidence limits, 60% to 72%) at 5 years, and 49% (70% confidence limits, 36% to 61%) at 10 years, indicating a continuing risk for premature death. Multivariate analysis identified preoperative ventricular function and hypertrophy as risk factors for survival. High postrepair right atrial pressure (greater than 15 mm Hg) emerged as a strong intraoperative predictor of survival. Logistic regression analysis of these factors predicts high probability of death for certain subgroups of patients after the Fontan operation. Forty-four percent (n = 53) of these original 124 patients are alive and in New York Heart Association class I at follow-up. Thirty-eight percent (n = 33) of survivors have worse ventricular function than preoperative. Long-term survival is disappointing. Certain identifiable subgroups of patients with univentricular heart have unacceptable risks for the Fontan operation and should have alternate management. High postrepair right atrial pressure is an ominous sign, and if it persists the Fontan should be fenestrated or taken down.
The Annals of Thoracic Surgery | 1989
Fred H. Edwards; Paul S. Schaefer; Amram J. Cohen; Ronald F. Bellamy; LeNardo Thompson; Geoffrey M. Graeber; Michael J. Barry
The relatively new field of artificial intelligence has spawned a variety of techniques associated with computer-assisted diagnosis. These techniques have been applied to the diagnosis of pulmonary lesions, but previous reports have focused on medical rather than surgical populations and the results have been evaluated using only retrospective patient surveys. We used a Bayesian algorithm to develop a diagnostic computer model for prospectively evaluating patients undergoing thoracotomy for suspected pulmonary malignancy. Patients who had a preoperative diagnosis were not included. Preoperative clinical and radiographic parameters for 100 consecutive patients were prospectively entered into the diagnostic model, which then categorized the lesion as benign or malignant. The computer predictions agreed with the final histological diagnosis in 95 of the 100 patients. The sensitivity was 96% and the specificity was 89% for this prospective series. These results indicate that the computer-assisted diagnosis of pulmonary lesions may have a role in this clinical setting.
The Annals of Thoracic Surgery | 1992
Amram J. Cohen; Alan K. Banks; Patrick A. Cambier; Fred H. Edwards
A 52-year-old man underwent an uneventful directional atherectomy of the left anterior descending coronary artery. Four months after the procedure unstable angina developed and on angiogram an aneurysm of the left anterior descending coronary artery was noted. The patient underwent bypass of the left anterior descending coronary artery. An attempt to exclude the aneurysm resulted in hemodynamic compromise and was discontinued. Follow-up angiogram 2 months after operation showed the aneurysm to be smaller. The patient is doing well 6 months after operation.
The Annals of Thoracic Surgery | 1988
Amram J. Cohen; James A. Ameika; Richard A. Briggs; Brent A. Grishkin; Robert A. Helsel
Thirty-two patients undergoing coronary artery bypass grafting were studied to evaluate retrograde flow in the internal mammary artery (IMA). The left IMA pedicle was prepared in routine fashion from the level of the first rib superiorly to just distal to the IMA bifurcation. Following cannulation for cardiopulmonary bypass but before institution of extracorporeal circulation, the IMA was divided 5 mm proximal to its bifurcation and allowed to bleed freely. The flow from each end was then measured by allowing the segment to bleed for 30 seconds. The mean antegrade flow was 73 +/- 34 ml/min, and the retrograde flow was 25 +/- 17.2 ml/min. The difference between the flows was significant (p less than 0.05). Based on these data we do not recommend the retrograde IMA technique as a primary form of revascularization of the myocardium. In selected circumstances it may be used if adequate retrograde flow is demonstrated before constructing the anastomosis.