Diagnostic dosages of protirelin (TRH) elevate BP by noncatecholamine mechanisms.

While performing thyroid function tests, we noticed that protirelin (TRH) raised BP, and, therefore, we investigated the effect of diagnostic dosages of protirelin (500 micrograms) on plasma catecholamine levels and cardiovascular function in eight patients one day before, one day after, and four weeks following heart surgery. Mean arterial pressure (MAP), heart rate (HR), plasma norepinephrine (NE), epinephrine (EPI), dopamine (DA), thyroid hormone (triiodothyronine [T3], thyroxine), and thyrotropin (TSH) levels were measured before and after the intravenous injection of protirelin. Protirelin increased MAP transiently from 88 +/- 2 to 103 +/- 3 mm Hg (before surgery), 86 +/- 4 to 102 +/- 4 mm Hg (one day after surgery), and 86 +/- 4 to 104 +/- 5 mm Hg (four weeks after surgery). There were no notable changes in HR or plasma NE, EPI, or DA levels. The T3 and TSH response to protirelin was normal on all three study days. Protirelin raised MAP by an effect on systemic vascular resistance (SVR) rather than an increase in cardiac output. We conclude the following: (1) diagnostic dosages of protirelin transiently elevate MAP and SVR by a noncatecholamine mechanism, (2) clinicians who perform protirelin tests should be aware of protirelin's transient pressor effects.

Evaluation of saphenous vein bypass surgery with multistage treadmill test and ventricular function studies.

The study includes 50 patients with severe, stable angina who have undergone the saphenous vein bypass operation. Patients were evaluated preoperatively and postoperatively with regard to exercise tolerance, incidence of stress-induced agina, ST-segment changes of ischemia, and ventricular function as indicated by stroke work index (LVSWI) and ejection fraction. Comparisons were made between patients with complete revascularization (CR) and patients with postoperative residual ischemia (RI). Results revealed that exercise duration improved significantly in both the CR and RI groups. In the CR group, angina and ischemic ST changes were completely eliminated. In the RI group, there was a 25 percent incidence of stress angina and a 50 percent incidence of ischemic ST-segment changes. In neither group was the ejection fraction significantly different from preoperative values. LVSWI decreased significantly in both groups postoperatively.

An alternate method of ventricular venting--the pulmonary artery sump.

The need for venting the heart during cardiopulmonary bypass has been the topic of continued debate. Potential disadvantages and drawbacks have been noted with traditional modes for venting. A technique for venting the heart is presented using a pulmonary artery catheter. The relative advantages and merits of this approach are discussed.

Bilateral atrial myxomas. Preoperative diagnosis and successful removal.

A case of bilateral atrial myxomas is presented. The diagnosis was made preoperatively with the aid of echocardiography and cineangiography. The use of the echocardiogram in the diagnosis of this lesion is emphasized.

Primary pericardial malignant epithelioid mesothelioma causing acute myocardial infarction.

A case of primary pericardial malignant epithelioid mesothelioma had an unusual presentation and emphasizes the urgency and possibility of antemortem diagnosis. Postmortem findings with electron microscopic studies document its histologic origin.

Isolated mitral valve replacement with the Kay-Shiley prosthesis. Long-term follow-up and recommendations.

Eighty patients underwent isolated mitral valve replacement with the Kay-Shiley prosthesis during a 6 year period (September, 1966, in October, 1972) at Walter Reed Army Medical Center. One-hundred percent follow-up has been achieved with this group. Sixty-four percent of this group have experienced one or more thromboembolic episodes (TEEs), for a TEE rate of 28.7 episodes per 1,000 patient months at risk. The 5 year survival rate is 45%. Eleven of 43 (25%) late deaths resulted from TEEs, and 13 of 43 (30%) late deaths were secondary in the hemorrhagic complications of long-term anticoagulant therapy. The dismal TEE rate prompted as to initiate a policy of elective replacement of all Kay-Shiley mitral prostheses. Eighteen of the 26 survivors underwent replacement of the Kay-Shiley mitral prosthesis. The other eight patients either declined reoperation or were not considered suitable candidates. The reoperative mortality rate was 22% (4/18). Fifteen of 18 explained prostheses revealed a yellow disclored, grooved occluder disc with loosely adherent clot. We recommend elective replacement of Kay-Shiley mitral prostheses in all patients in whom the risk of operation is reasonable.

Intrathoracic ganglioneuroblastoma.

Thirty-one patients treated for isolated intrathoracic ganglioneuroblastoma have been evaluated. The surviving patients (27/31) have been followed for periods up to 25 years. The modes of treatment consisted of complete or partial resection of the tumor, radiation therapy, or chemotherapy. Analysis of the data revealed that four patients treated with radiation alone died within 3 months after the start of treatment. Two patients had complete removal of the tumor without adjuvant therapy. Each is free of recurrent disease at 10 and 11 years postoperatively. The other 25 survivors had complete or incomplete surgical resection followed by radiation and/or chemotherapy. All are free of recurrent disease. Of the 25 patients who received postoperative radiation, 11 developed moderate-to-severe skeletal deformity. There appeared to be a correlation between deformity and the dose of radiation. Our current treatment recommendation consists of immediate operative intervention with an attempt at complete removal of the tumor. Patients with incomplete removal of tumor should be treated with radiation (2,000 r). Chemotherapy consisting of methotrexate or a combination of cyclophosphamide (Cytoxan) and vincristine should be reserved for patients with distant metastasis.

Surgical treatment of left main and left main equivalent coronary artery disease.

There is a tendency to equate left main (LM) and left main equivalent (LME) coronary artery disease in terms of the surgical risk and benefit. Eighty-seven patients with LM disease were compared to 78 patients with LME disease as to operative mortality rate and long-term benefits. One hundred percent follow-up was obtained. Although the two groups were similar preoperatively with regard to age, sex, and ventricular function, the operative results in the two groups differed. There was a significantly higher operative mortality rate in the LM group of patients (12.6% versus 2.5%). However, the incidence of graft patency and relief of symptoms was lower in the LME group of patients. The late mortality rate was 4% in both groups. LME disease appears to represent a subgroup of patients with three-vessel disease and cannot be equated with LM disease.

Value of anterior mediastinotomy in bronchogenic carcinoma of the left upper lobe.

Neoplasms of the left upper lobe may spread directly to the anterior mediastinal group of nodes without involving the inferior tracheobronchial, superior tracheobronchial, or paratracheal nodal chain. Routine cervical mediastinoscopy does not sample the anterior mediastinal node group. Parasternal anterior mediastinotomy was performed in 28 patients with left upper lobe carcinoma and normal findings from cervical mediastinoscopy. Despite the normal findings at cervical mediastinoscopy, 10 of the 28 patients were deemed to have inoperable disease because of spread of the neoplasm to the anterior nodal group or because of direct neoplastic involvement of the aorta or main pulmonary artery. All patients in whom results of anterior mediastinotomy were normal had resectable lesions at thoracotomy. Fourteen of the 16 patients who came to thoracotomy had normal hilar nodes. Parasternal anterior mediastinotomy, introduced by Chamberlain, should be performed in addition to standard cervical mediastinoscopy if the nodal drainage of left upper lobe neoplasms is to be more completely evaluated. Combining these two procedures samples all major drainage pathways except the posterior mediastinal nodal chain.

Creatine kinase and lactate dehydrogenase in the muscles encountered during median sternotomy and in the myocardium of the cardiac chambers.

The validity of using creatine kinase MB and lactate dehydrogenase serum isoenzymes to confirm the diagnosis of perioperative myocardial infarction in patients who have had cardiac operations has been questioned, since both have been detected in skeletal muscles. Little is known concerning the concentration of either isoenzyme in the muscles routinely encountered during median sternotomy. Since we have previously shown that the dog is an adequate model in which to study creatine kinase and lactate dehydrogenase isoenzymes, eight healthy dogs were placed under general anesthesia and 1 gm blocks were resected from selected muscles (intercostals, rectus abdominis, diaphragm, and sternothyroid) and from the walls of all four cardiac chambers. Each 1 gm block was homogenized individually in Ringer's lactate, centrifuged, and the supernatants were analyzed for total creatine kinase and lactate dehydrogenase activity by spectrophotometry. Isoenzymes were determined by agarose gel electrophoresis. The study shows that the chest wall muscles and atrial myocardium have appreciable quantities of creatine kinase MB. Hence, serum creatine kinase MB bands in the perioperative period can be generated by manipulation of chest wall muscles and the atrial wall as well as by infarction of the ventricular myocardium.

Coagulation abnormalities in patients undergoing myocardial revascularization.

One hundred patients were screened for hypercoagulability preoperatively and on the third, seventh, tenth, fourteenth, and twenty-first days postoperatively. Patients found to have hypercoagulability were treated with heparin, aspirin, and Coumadin. When the abnormality was present preoperatively, treatment was continued for the duration of the patient's life. Those patients in whom abnormalities developed postoperatively were given anticoagulants until cardiac catheterization 6 months following their operation. Twenty-four of the 100 patients had no coagulation abnormalities preoperatively or postoperatively. Fifteen patients were found to have abnormality prior to operation. Their predominant abnormality was low antithrombin III activity. Sixty-one patients became hypercoagulable postoperatively. Predominant abnormality in this group of patients was increased thrombin generation and increased platelet adhesiveness. Evaluation of patients in this study group revealed a decrease in the incidence of pulmonary embolism, an increase in the patency of vein grafts, and the elimination of anticoagulant therapy in 24 percent of the patients.

Dipyridamole-aspirin as thromboembolic prophylaxis in patients with aortic valve prosthesis. Prospective study with the Model 2320 Starr-Edwards prosthesis.

In a prospective study, the efficacy of a dipyridamole-aspirin regimen in prevention of thromboembolism was evaluated in 50 patients having isolated aortic valve replacement with the Model 2320 Starr-Edwards prosthesis. These operations were performed between February, 1972, and October, 1974. In 1,380 patient-months of follow-up, there was a 20% incidence of thromboembolism with a rate of 8.7/100 patient-years and a 19% probability of an embolic episode occurring by 3 years. Seven patients had transient episodes, two had permanent neurologic residua, and one patient died. Comparison is made to a similar group of patients having solitary aortic valve replacement but receiving no medication, studied by Starr and associates. There was no statistical difference in the incidence of thromboembolism between the two groups. In November, 1975, all patients were converted to a regimen of warfarin therapy. Since conversion to anticoagulation, there have been two thromboembolic episodes in 2,132 patient-months of follow-up for a rate of 1.1/100 patient-years. We conclude that the use of antiplatelet therapy in the form of dipyridamole-aspirin is inadequate for routine thromboembolic prophylaxis following SE 2320 aortic valve replacement.

Cystic lesion of the thymus. An occasionally malignant cervical and/or anterior mediastinal mass.

Between 1965 and 1982, we treated 46 patients with cystic lesions of the thymus. Thirty patients had anterior mediastinal cysts, nine had cysts which were large enough to be both cervical and mediastinal, and seven had cervical cysts. The majority (40/46) presented with asymptomatic masses. Six patients presented with distinct complaints: dysphagia (four patients), hoarseness owing to vocal cord paralysis (one patient), and cervical pain (one patient). All six had benign thymic cysts. The diagnosis of a cystic mass was established prior to operation by ultrasonography and computed axial tomography in our last three patients. These two techniques delineated the capsule and the central fluid in those three cases. All 46 patients had the mass resected without mortality or significant morbidity, except for resection of the phrenic nerve in one patient with malignant cystic thymoma. Cervical cysts were excised through cervical incisions. Cysts located in the anterior mediastinum and cervical-mediastinal cysts required median sternotomy or right thoracotomy for successful resection. Pathological examination showed that 39 patients had benign thymic cysts, three had benign cystic thymoma, two had malignant thymoma, one had a seminoma arising in the thymus, and one had a lymphoblastoma. We believe that a cystic thymic mass which can be detected by ultrasonography and computed tomography, although usually benign, does not eliminate the possibility of malignancy, and resection, therefore, is indicated.

Coagulation factors influencing thrombosis of aorta-coronary bypass grafts.

Thirty patients in whom all aorta-coronary artery vein grafts became occluded within one year of operation, as demonstrated by cardiac catheterization, were evaluated for hypercoagulability. A total of 59 grafts were constructed in these patients. At operation, blood flows of 35 to 90 c.c. per minute were measured through the grafts. In 23 of the 30 patients, the blood was to be hypercoagulable, as evidenced by a low level of antithrombin III activity, high thrombin generation index, high factor VII values, or high platelet adhesivity. Another group of 11 patients (total number of grafts, 23) had all grafts patent at cardiac catheterization. These patients had flows through the grafts ranging from 20 to 125 c.c. per minute. None of the patients with patent grafts had hypercoagulable blood. The status of runoff was comparable between the patients with open grafts and those with occluded grafts.

A comparison of patients with endoscopic esophageal perforations and patients with Boerhaave's syndrome.

A review was conducted to ascertain whether patients who suffered spontaneous postemetic esophageal rupture (Boerhaave's syndrome) experienced higher morbidity and mortality than patients who had endoscopic iatrogenic esophageal perforations. Review of the records of three medical centers from 1960 to 1985 identified 11 patients with Boerhaave's syndrome (group B) and 19 with iatrogenic perforations (group E). In group B, four patients were diagnosed greater than 24 h after perforation. Nine were treated surgically; of these one died. Two group B patients who were treated conservatively survived. In group E, only four patients were diagnosed greater than 24 h after perforation. Of 19 patients, 15 were treated surgically and four, medically. In group E, three patients died (one surgically and two conservatively treated). This study suggests that there is little difference in mortality between the two groups of patients as long as the diagnosis is made early and therapy is instituted promptly.

The use of computed tomography in the evaluation of mediastinal masses.

A retrospective analysis was conducted to ascertain whether computed tomography had increased diagnostic accuracy while decreasing the number of tests needed in the preoperative assessment of patients with mediastinal masses. A total of 42 patients were entered into the study: Fifteen patients were evaluated before the advent of computed tomography (No CT) and 27 patients had computed tomography during their evaluation (CT). The No CT group comprised 10 male and five female patients (2:1 ratio); the age range was 8 months to 61 years. The CT group included 15 male and 12 female patients (1.25:1.0 ratio), the age range being 21 to 70 years. In each group, both invasive and noninvasive studies were done. Although the CT group had 40 noninvasive tests, 27 were computed tomographic scans. The additional 13 noninvasive tests and the five invasive tests added no significant diagnostic information. In the No CT group, preoperative evaluation as to the cystic or solid nature of the mass was correct only four of 13 times (31%). In the CT group, 22 of 25 patients had accurate assessment as to the cystic or solid nature of the lesions (88%). In addition, extension of the mass into other structures, consistent with malignancy, was correctly diagnosed preoperatively in nine of the patients in the CT group. Two had extension of the mass at operation not preoperatively diagnosed (82% accuracy). None of the No CT group was given an assessment of possible mass extension preoperatively. The results suggest that mediastinal masses can be evaluated by computed tomography with a high degree of accuracy for predicting the nature, size, location, and involvement of other organs by the mass. The use of other tests before resection generally yields little additional information.

Changes in serum creatine kinase and lactate dehydrogenase caused by acute perioperative myocardial infarction and by transatrial cardiac surgical procedures.

A prospective clinical study was conducted to ascertain if a patient's postoperative elevation in serum creatine kinase MB isoenzyme coupled with determination of the lactate dehydrogenase1/lactate dehydrogenase2 ratio could differentiate whether atrial or ventricular myocardium was the source of these changes. Animal studies have shown that atrial myocardium is as rich a source of creatine kinase MB as is ventricular myocardium. Atrial myocardium has a lactate dehydrogenase1/lactate dehydrogenase2 ratio less than 1.00, whereas in ventricular myocardium the ratio is greater than 1.00. Sixty-four patients were assigned to six groups on the basis of serial electrocardiograms and vectorcardiograms by a cardiologist who was unaware of their clinical courses. The control group (Group 1) consisted of 16 patients admitted to the coronary care unit who had no electrocardiographic changes. Three surgical groups without electrocardiographic or vectorcardiographic evidence of perioperative myocardial infarction were studied: 10 patients undergoing routine coronary artery bypass procedures (Group 2), six adults undergoing repair of secundum atrial septal defect (Group 3), and 13 patients having mitral valve replacement (Group 4). Two groups of surgical patients who had acute perioperative transmural myocardial infarctions confirmed by serial electrocardiograms and vectorcardiograms were studied: 15 patients (Group 5) who had elective coronary artery bypass procedures and four (Group 6) who had mitral valve replacement. This study suggests that serum creatine kinase MB levels in excess of 50 IU/L on the postoperative day 1 and day 2 samples coupled with serum lactate dehydrogenase1/lactate dehydrogenase2 ratios greater than 1.00 on the postoperative day 2 and day 3 samples support the diagnosis of acute myocardial infarction. Patient groups undergoing procedures necessitating atriotomies had average elevations in serum creatine kinase MB and in the lactate dehydrogenase1/lactate dehydrogenase2 ratio, but these were significantly less than those seen when acute perioperative myocardial infarction had occurred.

Management of patients with malignant thymoma.

This report documents the results of therapy in 23 patients treated for malignant thymoma between 1944 and 1979. Of the group, 22 patients had neoplasms which invaded mediastinal structures; six had distant metastases. Four patients had myasthenia gravis and one had erythroid hypoplasia associated with collagen vascular disease. No deaths were associated with primary therapy, which included an operative procedure in all cases. Follow-up ranged from 4 months to 18 years (mean 5.63 +/- 1.03 years, SEM). Fifteen patients died, with postoperative survival times ranging from 4 months to 18 years (mean 3.8 +/- 1.27 years). Five patients were alive without recurrence from 3 to 11 years postoperatively (mean 6.8 +/- 1.36 years), and three patients were alive with recurrence or distant metastases from 4 to 17 years postoperatively (mean 10.75 +/- 2.66 years). Differences in survival on the basis of tumor cell type were not statistically significant. Therapeutic groups were analyzed for 5 year survivors, tumor deaths within 5 years of therapy, deaths due to other causes, deaths due to tumor after 5 years, those presently alive, and longest known survivor. The data suggest that complete surgical excision offers the best chance of long-term survival when compared to partial resection plus irradiation (p less than 0.05). No statistical significance could be demonstrated between the groups who had complete resection with versus without postoperative irradiation. There also was no statistically significant difference between the group of patients receiving irradiation following partial excision of most of their tumor and the group receiving irradiation following only biopsy of the lesion. This observation suggests there is no value in so-called "debulking procedures" and suggests that irradiation may be of value in local control of thymoma. Perpetual surveillance is necessary since late recurrence is common.

Relationship of triglyceride levels to thrombosis in patients with coronary artery disease.

The relationship of triglyceride levels to coagulation abnormalities was studied in 43 patients, who were divided into two groups. Group 1 consisted of patients with triglyceride levels less than 200 mg% (range, 75 to 190 mg%), and Group 2 consisted of patients with triglyceride levels greater than 250 mg% (range, 255 to 890 mg%). Analysis of the data revealed that patients with high triglyceride levels also have a high incidence of low antithrombin III activity and increased platelet aggregation. It is likely that hyperlipidemic patients are more prone to thrombosis of diseased coronary arteries or saphenous vein bypass grafts, and should definitely be placed on appropriate anticoagulants.

Use of intercostal muscle in primary repair of esophageal atresia with tracheoesophageal fistula.

Forty-one patients with esophageal atresia and distal tracheoesophageal fistula underwent primary repair. Results are compared among patients in whom an intercostal muscle graft was interposed between the trachea and esophagus and those without the graft. Patients with muscle interposition had lower morbidity and mortality and better long-term results.