The Journal of Thoracic and Cardiovascular Surgery, Jul 1, 1992
The role of retrograde coronary sinus cardioplegia in patients undergoing aortic valve replacemen... more The role of retrograde coronary sinus cardioplegia in patients undergoing aortic valve replacement for aortic stenosis alone or in combination with myocardial revascularization has not been fully defined. Sixty-three patients undergoing elective aortic valve replacement received cold potassium blood cardioplegic solution via either the aortic root (36 patients) or the coronary sinus (27 patients). The patients were similar with respect to age, degree of aortic stenosis, ventricular function, severity of coronary artery disease, crossclamp time, completeness of revascularization, and mean volume and temperature of the infusion solution. The mean septal temperature and the release of myocardium-specific isoenzyme in the first 2 hours after crossclamp removal was higher in the retrograde group (p less than 0.008). Right and left ventricular function was preserved equally in the two groups, and volume-loading studies suggested improved diastolic performance in patients having retrograde cardioplegia. There were no differences between the two groups with respect to clinical outcome. We conclude that coronary sinus cardioplegia is as safe as aortic root perfusion for myocardial preservation in patients undergoing elective aortic valve replacement.
The Journal of Thoracic and Cardiovascular Surgery, Jul 1, 1990
Ultrasonic decalcification of the aortic valve was performed in 22 elderly patients with critical... more Ultrasonic decalcification of the aortic valve was performed in 22 elderly patients with critical aortic stenosis (aortic valve areas less than 0.8 cm2) as an alternative to prosthetic valve replacement. All of the patients had symptoms. The mean New York Heart Association class was 3.3 +/- 0.9. Adequate decalcification with restoration of leaflet mobility was achieved in all patients, including seven with bicuspid aortic valves. Leaflet perforation occurred and was successfully repaired in five patients. Ten patients underwent concomitant myocardial revascularization. There were two operative deaths (9%) and three late deaths. Echocardiograms were obtained preoperatively, postoperatively, and at 6 months. The mean aortic valve area increased significantly from 0.72 +/- 0.17 to 1.42 +/- 0.31 cm2 (p less than 0.001) and the peak gradient decreased from 74 +/- 34 to 25 +/- 13 mm Hg (p less than 0.001). At 6 months the aortic valve area (1.29 +/- 0.48 cm2) and peak gradient (31 +/- 12 mm Hg) continued to be significantly better than the preoperative measurements (p less than 0.001), but the 6-month aortic valve area was slightly decreased and the gradient increased when compared with the immediate postoperative values (p less than 0.02). The prevalence of mild to moderate aortic insufficiency increased from 50% of the patients preoperatively to 87% at 6 months (p less than 0.05). Two patients subsequently required aortic valve replacement for restenosis and aortic insufficiency. Ultrasonic decalcification is effective in relieving aortic stenosis, but subsequent restenosis and insufficiency may limit its application.
In the 1990s, the concept of surgical therapy was introduced once again for the treatment of end-... more In the 1990s, the concept of surgical therapy was introduced once again for the treatment of end-stage emphysema. The earliest reports touted laser ablation of emphysematous lung as definitive therapy. Although some discernable benefit was reported, this was associated with significant operative morbidity. In 1993, the concept of parenchymal resection or "lung volume reduction" was reintroduced as treatment for end-stage lung disease. Over the ensuing 3 years, different techniques and approaches have evolved at different institutions. Lung volume reduction has been performed bilaterally and unilaterally through multiple approaches including sternotomy, thoracotomy, and thoracoscopy. The results of these various approaches are reviewed and compared. Lung volume reduction appears to be a beneficial procedure when performed in carefully selected patients by personnel and at institutions that are experienced in the care of patients with end-stage emphysema.
The purpose of this study was to determine if the addition of potassium to reinfusion cold blood ... more The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CBC (10 cc/kg) with potassium. Group I patients (n = 23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n = 17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.
Strategies to value physician work continue to evolve. The Society of Thoracic Surgeons and The S... more Strategies to value physician work continue to evolve. The Society of Thoracic Surgeons and The Society of Thoracic Surgeons National Database have an increasingly important role in this evolution. An understanding of the Current Procedural Terminology (CPT) system (American Medical Association [AMA], Chicago, IL) and the Relative Value Scale Update Committee (RUC) is necessary to comprehend how physician work is valued. In 1965, with the dawn of increasingly complex medical care, immense innovation, and the rollout of Medicare, the need for a common language describing medical services and procedures was recognized as being of critical importance. In 1966, the AMA, in cooperation with multiple major medical specialty societies, developed the CPT system, which is a coding system for the description of medical procedures and medical services. The RUC was created by the AMA in response to the passage of the Omnibus Budget Reconciliation Act of 1989, legislation of the United States of...
The purpose of this study was to determine if the addition of potassium to reinfusion cold blood ... more The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CBC (10 cc/kg) with potassium. Group I patients (n = 23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n = 17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.
Left main occlusive disease (LMD) is a potentially fatal lesion which is optimally treated with s... more Left main occlusive disease (LMD) is a potentially fatal lesion which is optimally treated with surgical revascularization. Although the internal thoracic artery (ITA) is recognized as having superior long term patency, there has been concern regarding possible flow limitation. Because of this concern, there may be reluctance to use only this conduit in patients with LMD in whom high graft flows are desirable. From 1985 to 1990, 45 patients (38 males, 7 females) with LMD ranging in age from 37 to 75 years (mean 55.9 +/- 8.7) underwent revascularization using bilateral ITA grafts placed to the left anterior descending and circumflex arteries. The right ITA was used as a free graft in 19 of 45 (42%) patients and the left ITA was used as a free graft in 3 of 35 (7%). No saphenous vein grafts were placed to the left coronary system in any patient. Over half of these patients (24 patients, 53%) also had occlusive disease in the right coronary artery. A saphenous vein graft was placed to the right coronary artery in 22 of 45 (49%) patients. Ventricular function in this patient subset was good (mean LV score 7.1 +/- 2.1). Intra-operative ITA graft flows were 49.7 +/- 29.1 ml/min for grafts to the left anterior descending and 45.5 +/- 31.7 ml/min for circumflex grafts. There were no perioperative deaths. Morbidity included myocardial infarction, stroke and reoperation for bleeding in 1 patient each (2.2%). Low cardiac output occurred in 2 patients (4.4%). No patient had a mediastinal wound infection.(ABSTRACT TRUNCATED AT 250 WORDS)
Symptomatic, nonsyphilitic, acquired coronary ostial stenosis is a rare angiographic finding and ... more Symptomatic, nonsyphilitic, acquired coronary ostial stenosis is a rare angiographic finding and was found in 0.13% of 3000 coronary angiograms. Three females with this lesion have been treated surgically. Two had left coronary ostial involvement. Coronary angiography may result in catheter tip occulsion of the ostium with chest pain, dyspnea, diaphoresis, systemic hypotension and abrupt fall in pressure at the catheter tip. Recognition of this entity is necessary for safe coronary angiography. Involvement of the left ostium carries the same serious prognosis as does left main coronary disease.
The Journal of Thoracic and Cardiovascular Surgery, Jul 1, 1992
The role of retrograde coronary sinus cardioplegia in patients undergoing aortic valve replacemen... more The role of retrograde coronary sinus cardioplegia in patients undergoing aortic valve replacement for aortic stenosis alone or in combination with myocardial revascularization has not been fully defined. Sixty-three patients undergoing elective aortic valve replacement received cold potassium blood cardioplegic solution via either the aortic root (36 patients) or the coronary sinus (27 patients). The patients were similar with respect to age, degree of aortic stenosis, ventricular function, severity of coronary artery disease, crossclamp time, completeness of revascularization, and mean volume and temperature of the infusion solution. The mean septal temperature and the release of myocardium-specific isoenzyme in the first 2 hours after crossclamp removal was higher in the retrograde group (p less than 0.008). Right and left ventricular function was preserved equally in the two groups, and volume-loading studies suggested improved diastolic performance in patients having retrograde cardioplegia. There were no differences between the two groups with respect to clinical outcome. We conclude that coronary sinus cardioplegia is as safe as aortic root perfusion for myocardial preservation in patients undergoing elective aortic valve replacement.
The Journal of Thoracic and Cardiovascular Surgery, Jul 1, 1990
Ultrasonic decalcification of the aortic valve was performed in 22 elderly patients with critical... more Ultrasonic decalcification of the aortic valve was performed in 22 elderly patients with critical aortic stenosis (aortic valve areas less than 0.8 cm2) as an alternative to prosthetic valve replacement. All of the patients had symptoms. The mean New York Heart Association class was 3.3 +/- 0.9. Adequate decalcification with restoration of leaflet mobility was achieved in all patients, including seven with bicuspid aortic valves. Leaflet perforation occurred and was successfully repaired in five patients. Ten patients underwent concomitant myocardial revascularization. There were two operative deaths (9%) and three late deaths. Echocardiograms were obtained preoperatively, postoperatively, and at 6 months. The mean aortic valve area increased significantly from 0.72 +/- 0.17 to 1.42 +/- 0.31 cm2 (p less than 0.001) and the peak gradient decreased from 74 +/- 34 to 25 +/- 13 mm Hg (p less than 0.001). At 6 months the aortic valve area (1.29 +/- 0.48 cm2) and peak gradient (31 +/- 12 mm Hg) continued to be significantly better than the preoperative measurements (p less than 0.001), but the 6-month aortic valve area was slightly decreased and the gradient increased when compared with the immediate postoperative values (p less than 0.02). The prevalence of mild to moderate aortic insufficiency increased from 50% of the patients preoperatively to 87% at 6 months (p less than 0.05). Two patients subsequently required aortic valve replacement for restenosis and aortic insufficiency. Ultrasonic decalcification is effective in relieving aortic stenosis, but subsequent restenosis and insufficiency may limit its application.
In the 1990s, the concept of surgical therapy was introduced once again for the treatment of end-... more In the 1990s, the concept of surgical therapy was introduced once again for the treatment of end-stage emphysema. The earliest reports touted laser ablation of emphysematous lung as definitive therapy. Although some discernable benefit was reported, this was associated with significant operative morbidity. In 1993, the concept of parenchymal resection or "lung volume reduction" was reintroduced as treatment for end-stage lung disease. Over the ensuing 3 years, different techniques and approaches have evolved at different institutions. Lung volume reduction has been performed bilaterally and unilaterally through multiple approaches including sternotomy, thoracotomy, and thoracoscopy. The results of these various approaches are reviewed and compared. Lung volume reduction appears to be a beneficial procedure when performed in carefully selected patients by personnel and at institutions that are experienced in the care of patients with end-stage emphysema.
The purpose of this study was to determine if the addition of potassium to reinfusion cold blood ... more The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CBC (10 cc/kg) with potassium. Group I patients (n = 23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n = 17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.
Strategies to value physician work continue to evolve. The Society of Thoracic Surgeons and The S... more Strategies to value physician work continue to evolve. The Society of Thoracic Surgeons and The Society of Thoracic Surgeons National Database have an increasingly important role in this evolution. An understanding of the Current Procedural Terminology (CPT) system (American Medical Association [AMA], Chicago, IL) and the Relative Value Scale Update Committee (RUC) is necessary to comprehend how physician work is valued. In 1965, with the dawn of increasingly complex medical care, immense innovation, and the rollout of Medicare, the need for a common language describing medical services and procedures was recognized as being of critical importance. In 1966, the AMA, in cooperation with multiple major medical specialty societies, developed the CPT system, which is a coding system for the description of medical procedures and medical services. The RUC was created by the AMA in response to the passage of the Omnibus Budget Reconciliation Act of 1989, legislation of the United States of...
The purpose of this study was to determine if the addition of potassium to reinfusion cold blood ... more The purpose of this study was to determine if the addition of potassium to reinfusion cold blood cardioplegia (CBC) offers an advantage over cold blood alone. Forty patients matched for age, left ventricular function, extent of coronary disease and number of vessels bypassed were prospectively randomized. Each patient received an initial dose of CBC (10 cc/kg) with potassium. Group I patients (n = 23) received subsequent infusions of CBC (5 cc/kg) containing potassium while Group II patients (n = 17) received cold blood only. The cross-clamp time, mean infusate volume and temperature were not significantly different in the two groups. Following reperfusion, the cardiac index and the CPK isoenzyme release at 0.5, 1, 8, and 12 h after cross-clamp release were not significantly different between the groups. The postoperative appearance of new Q-waves, inotropic agent requirement, and reversal of the lactate dehydrogenase (LDH) isoenzyme ratio were also not significantly different in the two groups. The study demonstrated that following initial arrest with potassium, cold blood is equally as effective as potassium blood cardioplegia in protecting the ischemic myocardium.
Left main occlusive disease (LMD) is a potentially fatal lesion which is optimally treated with s... more Left main occlusive disease (LMD) is a potentially fatal lesion which is optimally treated with surgical revascularization. Although the internal thoracic artery (ITA) is recognized as having superior long term patency, there has been concern regarding possible flow limitation. Because of this concern, there may be reluctance to use only this conduit in patients with LMD in whom high graft flows are desirable. From 1985 to 1990, 45 patients (38 males, 7 females) with LMD ranging in age from 37 to 75 years (mean 55.9 +/- 8.7) underwent revascularization using bilateral ITA grafts placed to the left anterior descending and circumflex arteries. The right ITA was used as a free graft in 19 of 45 (42%) patients and the left ITA was used as a free graft in 3 of 35 (7%). No saphenous vein grafts were placed to the left coronary system in any patient. Over half of these patients (24 patients, 53%) also had occlusive disease in the right coronary artery. A saphenous vein graft was placed to the right coronary artery in 22 of 45 (49%) patients. Ventricular function in this patient subset was good (mean LV score 7.1 +/- 2.1). Intra-operative ITA graft flows were 49.7 +/- 29.1 ml/min for grafts to the left anterior descending and 45.5 +/- 31.7 ml/min for circumflex grafts. There were no perioperative deaths. Morbidity included myocardial infarction, stroke and reoperation for bleeding in 1 patient each (2.2%). Low cardiac output occurred in 2 patients (4.4%). No patient had a mediastinal wound infection.(ABSTRACT TRUNCATED AT 250 WORDS)
Symptomatic, nonsyphilitic, acquired coronary ostial stenosis is a rare angiographic finding and ... more Symptomatic, nonsyphilitic, acquired coronary ostial stenosis is a rare angiographic finding and was found in 0.13% of 3000 coronary angiograms. Three females with this lesion have been treated surgically. Two had left coronary ostial involvement. Coronary angiography may result in catheter tip occulsion of the ostium with chest pain, dyspnea, diaphoresis, systemic hypotension and abrupt fall in pressure at the catheter tip. Recognition of this entity is necessary for safe coronary angiography. Involvement of the left ostium carries the same serious prognosis as does left main coronary disease.
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Papers by Keith Naunheim