Lung cancer resection or aortic graft replacement with simultaneous myocardial revascularization without cardiopulmonary bypass.

BACKGROUND: The concomitant occurrence of lung cancer or other thoracic problems requiring surgical treatment in patients with significant coronary artery disease is uncommon. METHODS: Three patients underwent revascularization of the anterior descending artery, without cardiopulmonary bypass, with simultaneous pulmonary lobectomy (two patients) or replacement of an obstructed descending aortic graft (one patient). RESULTS: Postoperative ventilation time was < 3 h, and no morbidity related to the combined procedure occurred during midterm follow-up. CONCLUSIONS: This one-stage approach allowed the immediate solution of two intrathoracic comorbidities, reducing expenses and suffering to the patients and minimizing the risk of bleeding or tumor dissemination secondary to extracorporeal circulation-induced coagulopathy and immunosuppression.

[Concomitant surgery--coronary artery bypass and pulmonary lobectomy].

Coronary artery disease amenable to percutaneous interventions or coronary artery bypass grafting, and resectable lung cancer are major causes of morbidity and mortality. We present our experience in the treatment of 3 patients (men aged 64 and 66 and a woman of 77) who each had significant coronary artery disease and a resectable lung tumor. They underwent combined coronary artery bypass grafting and pulmonary lobectomy. We conclude from our experience and review of the literature that concomitant surgery in such cases is safe and effective, decreases suffering, and decreases the cost of 2 separate invasive procedures.

Mitral valve replacement in patients after aortic valve replacement.

BACKGROUND: Mitral valve replacement in patients who previously had undergone aortic valve replacement is a technical challenge. The rigid aortic prosthesis limits visualization of the anterior mitral annulus and placement of sutures. METHODS: Reoperative mitral valve replacement was performed in five patients after aortic valve replacement. Two patients underwent resternotomy to allow verification of normal aortic prosthetic valve function. Anterolateral right thoracotomy was used for reentry in the remaining three patients. Exposure of the anterior mitral annulus was accomplished by initial traction on the intact anterior leaflet, with resection of this leaflet only after placement of sutures. RESULTS: All patients survived the surgical procedure and are well 2 to 30 months after operation. In one patient it was impossible to open one cusp of the mitral prosthesis, nor was it possible to rotate the valve. The valve was reimplanted, but sutures were tied only after testing for full free cusp motion. CONCLUSIONS: When appropriate, right thoracotomy incision offers excellent exposure of the mitral valve with minimal dissection. Placement of sutures along the anterior portion of the annulus is facilitated by traction downwards on the anterior leaflet. Full range of motion of the prosthetic cusps should be verified before tying the sutures.

[Treatment of concomitant coronary and carotid disease].

The optimal surgical treatment for concomitant carotid and coronary artery disease is controversial. Between 1991 and 1995 we performed 34 procedures for combined disease of the carotid and coronary arteries. The first 8 operations were carotid endarterectomies followed by coronary artery bypass grafting (staged procedure). The next 26 operations were performed during a single anesthesia (combined procedure). The patients were 28 men and 6 women, aged 58-81 years (mean 68). 80% were in functional class III or IV. In 40% ventricular function was moderately or severely reduced. There was an average of 3.6 grafts per patient, and in all except 3 patients the left internal thoracic artery was used as a conduit for coronary artery bypass grafting. 30% had symptomatic carotid stenosis; there was no perioperative mortality. In the staged procedure group, 2 patients had postoperative cardiac complications: in 1 acute coronary insufficiency and acute myocardial infarction in the other. 1 had postoperative, transient, amaurosis fugax. In the combined procedure group, 1 had a myocardial infarction and 1 a minor occipital stroke. During follow-up, 1 patient died 4 months after operation of myocardial infarction, and 1 had a minor stroke. The results suggest that the combined procedure is safe and carries low risk of both mortality and morbidity. Whenever cardiac disease is stable and there is no main coronary artery disease, a staged procedure should be considered. In any other situation we continue to perform the combined procedure.

[Successful single-lung transplantation in emphysema].

Lung transplantation is now considered acceptable therapy for end-stage lung disease. Until recently therapy for emphysema was disappointing, but lung transplantation has brought new hope for those terminally ill with the disease. We present our early experience with single-lung transplantation in 5 men and 1 woman with emphysema, 40-61 years old. All recovered following surgery, with remarkable improvement in lung function and functional capacity. They are now 6-20 months post-transplantation, do not need oxygen supplementation and are able to perform their normal daily activities. Shortage of donor organs is the limiting factor for single-lung transplantation in these patients.

Extracellular and standard University of Wisconsin solutions provide equivalent preservation of myocardial function.

The deleterious effect of hyperkalemic cardioplegic solutions on coronary endothelium has been documented and has also been demonstrated with University of Wisconsin solution. We evaluated a new extracellular University of Wisconsin formulation for efficacy in heart preservation. Six neonatal piglet hearts were arrested with and stored in the standard intracellular University of Wisconsin solution (group 1: K+ 125 mEq/L, Na+ 29 mEq/L). Six piglet hearts were preserved for 24 hours with an extracellular University of Wisconsin solution that differed only in the concentrations of potassium and sodium (group 2: K+ 25 mEq/L, Na+ 129 mEq/L). Hearts underwent modified reperfusion with leukocyte-depleted aspartate-glutamate enriched blood cardioplegic solution followed by conversion to a left-sided working mode on a Langendorff circuit with perfusion from a support pig. Stroke work index was calculated at left ventricular end-diastolic pressures of 3, 6, 9, and 12 mm Hg. Sixty minutes after reperfusion, there was no significant difference in stroke work index between group 1 (16.4 +/- 1.9 x 1000 erg/gm) and group 2 (15.3 +/- 2.7 x 1000 erg/gm). There was also no significant difference in high-energy phosphate stores or myocardial water content between the two groups. Extracellular University of Wisconsin solution provides myocardial preservation equivalent to standard University of Wisconsin solution while preventing exposure of coronary endothelium to high levels of potassium, which justifies its use in clinical heart transplantation.

University of Wisconsin solution versus Stanford cardioplegic solution and the development of cardiac allograft vasculopathy.

BACKGROUND: University of Wisconsin (intracellular) solution has been shown to offer some distinct benefits of myocardial preservation over Stanford (extracellular) solution, including a more rapid functional recovery, improved adenosine triphosphate preservation, and a tendency for less postoperative inotropic agents. However intracellular solutions with high potassium content have been reported to cause a functional if not structural endothelial injury in laboratory experiments. METHODS: Because of this information we retrospectively viewed our follow-up angiographic data for the development of the cardiac allograft vasculopathy in a consecutive series of 195 heart transplant recipients. These patients were treated in identical fashion, with the same immunosuppression regimen, except for the type of cardioplegia used--Stanford solution (group I n = 95) and University of Wisconsin solution (group II n = 100). RESULTS: With a mean follow-up of 24 months after transplantation, a significant difference was seen in the development of cardiac allograft vasculopathy in group II (22%) versus group I (14%, p < 0.03). Although significant differences were observed with univariate analysis with respect to donor age and ischemic time favoring group I and with multivariate statistical analysis with respect to overall rejections favoring group II, the only significant variable for the difference in the development of allograft vasculopathy was University of Wisconsin cardioplegic solution (p < 0.003). A subgroup of 30 patients previously randomized for a functional study comparing the two cardioplegic agents showed a tendency for statistical significance with a freedom from allograft vasculopathy of 93% in group I, as compared with 83% in group II, after 13 months follow-up (p = 0.09). The overall probability of being free of vasculopathy at 24 months was 86% for group I and 70% for group II. CONCLUSIONS: The data support the conclusion that University of Wisconsin intracellular solution is associated with an increased incidence of vasculopathy versus Stanford solution and warrants investigation for modification of this preservation agent in heart transplantation.

The regional capillary distribution of retrograde blood cardioplegia in explanted human hearts.

Warm retrograde blood cardioplegia is frequently used for myocardial protection, despite experimental studies questioning the adequacy of capillary flow to the right ventricle and septum. The capillary distribution of retrograde blood cardioplegia in the human heart is unknown. Hearts from eight transplant recipients with the diagnosis of idiopathic or dilated cardiomyopathy were arrested in situ with cold blood cardioplegia and excised with the coronary sinus intact. Within 20 minutes of explanation, colored microspheres mixed in 37 degrees C blood cardioplegia were administered through the coronary sinus at a pressure of 30 to 40 mm Hg for 2 minutes. Twelve transmural myocardial samples were taken horizontally at the level of midventricle and apex to determine regional capillary flow rates. When retrograde warm blood cardioplegia was administered at a rate of 0.42 +/- 0.06 ml/gm/min, the left ventricle, the septum, the posterior wall of the right ventricle, and the apex consistently received capillary flow rates in excess of their metabolic requirements. The capillary perfusion of anterior and lateral walls of the right ventricle was marginally adequate to sustain aerobic metabolism. In explanted human hearts, retrograde blood cardioplegia provides adequate capillary flow to the left ventricle, the septum, the posterior wall of the right ventricle, and the apex; however, capillary flow to the anterior and lateral walls of the right ventricle is marginal. This study delineates the tenuous balance between supply and demand for right ventricular protection with warm continuous retrograde blood cardioplegia.

Coronary sinus ostial occlusion during retrograde delivery of cardioplegic solution significantly improves cardioplegic distribution and efficacy.

UNLABELLED: This study documents the gross flow characteristics and capillary distribution of cardioplegic solution delivered retrogradely with the coronary sinus open versus closed. METHODS: Five explanted human hearts from transplant recipients were used as experimental models. Hearts served as their own controls and received two doses of warm blood cardioplegic solution, each containing colored microspheres. The first dose was delivered through a retroperfusion catheter with the coronary sinus open and the second dose was delivered with the sinus occluded. Capillary flow was measured at twelve ventricular sites and gross flow was measured by examining coronary sinus regurgitation, thebesian vein drainage, and aortic effluent (nutrient flow). RESULTS: Coronary sinus ostial occlusion allowed for a significant decrease in total cardioplegic flow (1.74 +/- 0.40 ml/gm versus 1.06 +/- 0.32 ml/gm; p < 0.05) to occur while maintaining an identical intracoronary sinus pressure. Ostial occlusion also resulted in an increase in the ratio of nutrient flow/total cardioplegic flow from 32.3% +/- 15.1% to 61.3% +/- 7.9% (p < 0.05). A statistically significant improvement in capillary flow was found at the midventricular level in the posterior intraventricular septum and posterolateral right ventricular free wall. This improvement was also documented for the intraventricular septum and right ventricle at the level of the apex. CONCLUSION: Coronary sinus occlusion during retrograde cardioplegia significantly improves cardioplegic delivery to the right ventricle and posterior intraventricular septum. Furthermore, the technique affords a significant improvement in nutrient cardioplegic flow while reducing the overall volume of cardioplegic solution administered.

Effects of magnesium on myocardial function after coronary artery bypass grafting.

The effects of perioperative administration of magnesium sulfate on myocardial function was studied in patients with unstable angina (grade IV) undergoing coronary artery bypass grafting. Myocardial protection consisted of antegrade and retrograde continuous warm blood cardioplegia. Patients were randomly divided into two groups. Group A (50 patients) received intravenous magnesium sulfate (16 mmol) continuously from the time of anesthetic induction to aortic cross-clamping and a second dose (32 mmol) starting after the release of aortic cross-clamp until 24 hours later. Group B (48 patients) did not receive magnesium sulfate and served as control. Left ventricular stroke work index increased in group A from 34 +/- 3 g.m/m2 before operation to 42 +/- 3 g.m/m2, 45 +/- 2 g.m/m2, and 47 +/- 2 g.m/m2, 1, 6, and 12 hours after operation, respectively (p < 0.05 versus preoperative), and in group B from 33 +/- 3 g.m/m2 before operation to 38 +/- 3 g.m/m2, 40 +/- 2 g.m/m2, and 41 +/- 2 g.m/m2, 1, 6, and 12 hours after operation, respectively (p < 0.05). Left ventricular stroke work index was higher in group A 6 (p = 0.06), 12, and 24 hours (p < 0.05) after operation compared with group B. The incidence of ventricular arrhythmias requiring treatment was significantly higher (p < 0.05) in group B: 14 patients versus 1 patient in group A. Postoperative hypertension was more frequent in group B: 16 patients versus 2 patients in group A (p < 0.05). These results indicate that perioperative administration of magnesium sulfate may contribute to better myocardial recovery and fewer ventricular tachyarrhythmias after operation.

Usefulness of late potentials on the immediate postoperative signal-averaged electrocardiogram in predicting ventricular tachyarrhythmias early after isolated coronary artery bypass grafting.

The present study was undertaken to determine the value of abnormal late ventricular potentials on signal-averaged electrocardiograms (ECG) in identifying patients at risk of developing ventricular tachycardia or ventricular fibrillation in the early postoperative period after coronary artery bypass grafting. Signal-averaged ECGs were recorded immediately after operation in 72 patients. Abnormal late potentials were defined as the presence of 2 or 3 of the following: (1) root-mean-square amplitude of the last 40 ms of the QRS < 20 microV; (2) duration of the terminal QRS potentials (after 40 microV) > or = 39 ms; and (3) high-frequency QRS duration > 120 ms (in patients with conduction defects, only the first 2 criteria were used). Abnormal late ventricular potentials were present on the immediate postoperative signal-averaged ECG in 26 of the 72 patients (36%). Life-threatening ventricular tachyarrhythmias occurred in 6 patients. Late potentials were present in all 6 patients, but only in 20 of 66 (30%) who did not develop ventricular tachyarrhythmias (p < 0.005) (sensitivity 100%, specificity 70%, predictive accuracy 72%). Of 12 pre- and perioperative variables examined by univariate and multivariate regression analysis, the presence of late potentials on the signal-averaged ECG and low cardiac output postoperatively were found to be independent predictors of life-threatening tachyarrhythmias.

Early and late results of mitral valve repair in children.

Mitral valve repair in children has the advantage of avoiding mitral valve replacement with its attendant need for anticoagulation and reoperation. Seventy-nine children between the ages of 2 months and 17 years (mean 4.9 years) underwent mitral valve repair between May 1982 and April 1993. There were five patients with mitral stenosis and 74 patients with mitral regurgitation, and 19 children were less than 2 years of age. Patients were divided into anatomic subgroups on the basis of the primary cardiac pathologic condition. Forty-three had severe mitral regurgitation, 21 had moderate mitral regurgitation, and 12 patients with primum atrial-septal defect and 2 patients with univentricular hearts had minimal to moderate mitral regurgitation. Associated cardiac anomalies were present in 68 patients and 85% of the patients required concomitant intracardiac procedures. The methods of mitral valve repair included annuloplasty in 68 (86%), repair of cleft leaflet in 41 (52%), chordal shortening in 9 (11%), triangular leaflet resection in 8 (10%), splitting of papillary muscles with resection of subvalvular apparatus in 7 (9%), and chordal substitution in 1 (1%). The technique of annuloplasty was modified to allow for annular growth. Follow-up was available from 1 to 10 years (mean 4 +/- 2.5 years). There were three early deaths (4%), all occurring as a result of low output cardiac failure in patients with minimal postoperative mitral regurgitation. Three late deaths (4%) occurred in patients with persistent moderate to severe mitral regurgitation and progressive cardiac failure and eight patients (10%) required either rerepair or replacement of the mitral valve. Actuarial survival was 94% at 1 year, 84% at 2 years, and 82% at 5 years, and actuarial freedom from reoperation was 89% at 8 years. All patients received postoperative echocardiography with 82% having minimal to no mitral regurgitation and 98% of long-term surviving patients being free of symptoms. We conclude that mitral valve repair can be done with low early and late mortality. The need for reoperation is relatively low and valve growth has occurred with the use of a modified annuloplasty.

[Autotransfusion of shed mediastinal blood after cardiac surgery].

We have developed a technique for autotransfusion of shed mediastinal blood collected in the cardiotomy reservoir. Results in the first 50 consecutive patients in whom the system was employed were studied prospectively (group A) and were compared with those of the last 50 consecutive patients operated on before application of the new method (group B). The mean preoperative hematocrit (about 42%) and the total postoperative bleeding (about 11) were similar in both groups. Only 24 patients (48%) in group A required homologous blood transfusion, versus 43 (86%) in group B (p = 0.0001). This resulted in a 57% saving of blood units in group A (mean, 1.16 +/- 1.49 units per patient versus 2.72 +/- 1.99 in group B, p less than 0.0001). Foreign blood transfusion was thus avoided in 21 of the last 25 patients (84%) of group A. 7 days after operation, the mean hematocrit in group A was 30.9 +/- 4.3, compared with 33.0 +/- 3.8 in group B (p less than 0.001). Hemolytic jaundice occurred in 7 group B patients (14%) but in none in group A (p less than 0.01). A trend towards reduction in other complications was also demonstrated. We conclude that the use of foreign blood transfusions in those undergoing open heart surgery can be reduced significantly by this method, thus avoiding immediate transfusion reactions and minimizing the risks of late complications.