Treatment of ventricular tachycardia using an automatic scanning extrastimulus pacemaker.

A patient with recurrent sustained ventricular tachycardia that was resistant to both conventional and experimental antiarrhythmic agents was treated with a programmable automatic scanning extrastimulus pacemaker. The antitachycardia pacemaker was implanted only after many episodes of spontaneous and laboratory-induced ventricular tachycardia were reliably and reproducibly terminated with programmed ventricular extrastimuli. In the 6 months since implantation of the automatic scanning pacemaker, all episodes of ventricular tachycardia have been terminated successfully by the pacemaker. Acceleration of rate of ventricular tachycardia or induction of ventricular fibrillation did not occur at any time during attempted termination of ventricular tachycardia by the pacemaker. The advantages of the automatic scanning extrastimulus pacemaker over other antitachycardia pacemakers are discussed.

Ventriculocoronary connections in hypoplastic right heart syndrome: autopsy serial section study of six cases.

Myocardial sinusoids communicating with the coronary systems occur in pulmonary atresia with intact ventricular septum. To test the hypothesis that the extent of ventriculocoronary connections correlates with the degree of right ventricular outflow obstruction as evidenced by clinical, angiographic and gross anatomic findings, a serial section study of six human autopsy hearts representing a spectrum of hypoplastic right heart was undertaken. Slides were evaluated for the presence and extent of ventriculocoronary connections, associated developmental abnormalities and secondary changes in the ventricular walls. Whereas extensive blind-ended deep sinusoids were a feature of all five cases with unrelieved obstruction, ventriculocoronary connections were identified in three. Changes that suggested ongoing remodeling provide new evidence for the postnatal temporal evolution of these anomalous communications. The regional distribution of myofiber disarray in hypoplastic right heart supports the concept that vascularization parallels myocardial organization in the developing human heart.

Anomalous left coronary artery from the pulmonary artery: significance of associated intracardiac defects.

Two patients with anomalous origin of the left main coronary artery from the pulmonary artery had an associated defect (one, critical pulmonary stenosis; the other, ventricular septal defect). They presented with signs and symptoms of the associated defect and the coronary anomaly was unrecognized. Both cases at autopsy lacked the usual large right coronary artery seen with this anomaly. The pathophysiologic features of the combined defects are described, their differences from the isolated anomaly are noted and their relation to surgery is discussed.

Effects of hypothermia on propranolol kinetics.

Propranolol may be uniquely useful in cardiac surgical procedures, since beta adrenergic blockade can prevent the hypokalemia and associated arrhythmias which result from systemic hypothermia. To determine the effects of hypothermic cardiopulmonary bypass (HCPB) on the in vivo handling of propranolol, serial drug plasma concentrations (Cp) were measured during HCPB in 12 patients who had been treated chronically with propranolol prior to surgery. Although no further propranolol was given during the procedure, Cp values (corrected for plasma volume dilution) were higher during hypothermia than in the preoperative period, falling to or below control levels after rewarming. Due to the variables inherent in patient surgery, meaningful kinetic analysis could not be carried out. Therefore, intravenous propranolol (1 mg/kg) was given twice to each of 5 dogs, first after anesthesia only, then after anesthesia and systemic cooling to 26 degrees in a water bath Cp values measured serially over 2 hr after drug administration were consistently higher during hypothermia. Compared with the paired normothermic control studies, hypothermia markedly reduced the apparent volume of distribution (6.78 +/- 1.65 vs 2.08 +/- 0.58 L/kg; p less than 0.001) and the total body clearance of propranolol (64.4 +/- 11.0 vs 32.3 +/- 7.2 ml/kg/min; p less than 0.005). These data show that hypothermia substantially alters the pharmacokinetics of propranolol, resulting in plasma drug levels higher than those predicted from kinetic patterns derived under normothermic conditions.

Late isolated left ventricular tamponade. Clinical, hemodynamic, and echocardiographic manifestations of a previously unreported postoperative complication.

A unique case of late postoperative left ventricular tamponade, hemodynamically indistinguishable from severe left ventricular failure, is reported in a patient 1 month after an apparently uncomplicated aortic valve replacement. An echo-free space behind the left ventricle led to surgical exploration and successful resolution of the disease process. To our knowledge, this is the first documented case of isolated left ventricular tamponade in the literature. The findings highlight the importance of postoperative echocardiography in the evaluation of the patient having cardiac surgery.

A simple technique for multiorgan preservation.

A simple technique for multiorgan preservation with no ischemic time was developed. In five mongrel dogs, the heart and lungs were separated and removed with the liver, pancreas, kidneys, and a small portion of intestine en bloc while they were being self-perfused. A respirator was used for oxygenation. Arterial and venous blood pressures were measured by indwelling catheters. Fresh blood, glucose, electrolytes, mannitol, prednisolone, and a fat emulsion (Soyacal) were infused through the portal vein. The organs were experimentally perfused for 12 hours. Aortic systolic pressure ranged from 75 to 125 mm Hg, central venous pressure from 0 to 5 mm Hg, portal venous pressure from 0 to 3 mm Hg, bile output from 5 to 20 ml/hr, urine output from 10 to 70 ml/hr, and hematocrit value from 35% to 55%. The heart and lungs were normal and physiologically functional during the preservation time. The pancreas and small intestine appeared normal. Three of the livers showed some congestion. The kidney in one organ block appeared to have some edematous swelling after 16 hours. The technique for multiorgan preservation presented here is simple and effective. The preliminary data are encouraging and suggest further evaluation.

Anomalous double blood supply to the lung.

We report an unusual case in which an apparently normal upper lobe of the right lung was supplied by major systemic arterial and pulmonary arterial vessels. The anomalous artery arose from the descending aorta. Following interruption of this vessel, the machinery-like murmur previously present disappeared.

Giant tracheoesophageal fistula: management by esophageal diversion.

Giant tracheoesophageal fistulas complicating the management of respiratory insufficiency are often difficult to close successfully because of suture line tension and narrowing of the trachea or esophagus or both. Recovery of lung function often depends on successful diversion of gastrointestinal contents from the tracheobrachial tree. We have managed six patients with giant tracheoesophageal fistula. In three cases the lesions were related to overinflation of low-pressure balloon cuffs. The only survivors were two of three patients managed by esophageal diversion and reconstruction through extrathoracic incisions. The techniques, advantages, and disadvantages of esophageal diversion for giant tracheoesophageal fistula are presented.

Results and patterns of perioperative myocardial infarction.

Myocardial injury during a variety of cardiac surgical operations was determined in 57 patients by serial electrocardiograms (ECG's), serial determinations of serum creatine phosphokinase (CPK), and perioperative and postoperative technetium-99m stannous pyrophosphate (PYP) scans. ECG evidence of injury developed in four patients, whereas positive localized injury by PYP scan developed in ten. Twenty-one patients had elevated CPK enzymes postoperatively. The localization of injury by PYP scan correlated with ECG evidence of infarction in only one of four patients. Localized left ventricular injury by PYP scan without new Q waves on the ECG was common (5/12) in patients undergoing aortic valve replacement with perfusion of the coronary arteries. The injury in patients with congenital heart disease occurred at sites of ventricular incision or suggested possible air embolization of the coronary arteries. Perioperative infarction is frequently segmental and nontransmural and occurs in patients with coronary, valvular, and congenital heart disease.

Shunting, release, and distribution of nine and fifteen micron spheres in myocardium.

The shunting, release, and transmural distribution of 9 and 15 mu radioactive microspheres were compared in isolated hearts and intact hearts with and without adenosine triphosphate (ATP) vasodilation. ATP vasodilation caused increase shunting of 9 mu spheres but not 15 mu spheres (p less than 0.05). The transmural distribution of 9 and 15 mu spheres in left ventricle and septum were significantly different (p less than 0.01) and the difference was characteristic for the isolated heart and the nonvasodilated intact heart. There was no difference in distribution across the right ventricle. There appear to be significant differences in regional shunting as well as distribution in the intact heart. We found no systematic correction for comparing flows measured with 9 and 15 mu spheres.

Pericardial flap to minimize internal mammary artery anastomotic tension.

A technique is described that decreases tension on the left internal mammary artery anastomosis in patients whose lungs have herniated across the midline.

Upper rib fractures following median sternotomy.

First and second rib fractures occurred in 11 (16%) of 69 patients undergoing median sternotomy. Although 6 patients had no symptoms related to the rib fractures, 5 patients had postoperative chest, shoulder, and arm pain suggestive of angina pectoris or postpericardiotomy syndrome. The correct diagnosis of pain related to postoperative upper rib fracture may be made by direct visualization of the fracture on supine anteroposterior radiographs, elicitation of pain by palpation of the rib or motion of the upper extremity, lack of response to nitroglycerin, and negative electrocardiogram and cardiac enzyme levels. Upper rib fractures following median sternotomy are usually radiographically detectable within the first three postoperative days. Placement of the Ankeney sternal retractor with the upper blade in a lower position (fourth intercostal space) may reduce the incidence of this postoperative complication.

Management of ascending aortic aneurysm complicating coarctation of the aorta.

Four patients with coarctation of the aorta complicated by an aneurysm of the ascending aorta are described. One patient, treated only medically, died suddenly. For the 3 patients who underwent operation, management was similar. Pharmacological control of blood pressure and repair of the aortic coarctation to achieve anatomical reduction in afterload (stage I) were followed after an interval of one to five weeks by surgical repair of the ascending aortic aneurysm (stage II). Initial repair of the coarctation relieves proximal hypertension, thereby decreasing the chance of progressive dissection or rupture of the aneurysm. It also permits safe arterial cannulation for perfusion during correction of the aneurysm in the second stage. In patients not requiring valve replacement in stage II, continued long-term follow-up for progression of aortic valvular disease appears to be necessary.

Structure-related thrombosis involving a porcine xenograft valve.

A patient developed acute congestive heart failure following chordal rupture and underwent mitral valve replacement with a porcine xenograft. He recovered adequate hemodynamic function but died one month later with widespread bronchopneumonia. Postmortem examination revealed a prominent muscular shelf in the right coronary leaflet of the xenograft, and focal thrombosis involving the adjacent sewing ring and left atrial wall. The location of the thrombus suggests that it formed as a result of local stasis behind the large muscular shelf. Limiting the size of this muscular shelf by valve selection and construction may reduce the thrombogenicity of this prosthesis.

Repair of chest wall defects with prosthetic material.

This report summarizes our experience during a four-year period with the repair of 8 thoracic cage and 3 diaphragmatic defects requiring reinforcement with prosthetic material. Defects as large as the entire left hemidiaphragm or the right anterior chest wall including ribs two through six from the midsternum to the midaxillary line were adequately repaired. The technical approach utilized to obtain a secure, nonmobile thoracic cage involved the placement of sutures through drill holes or around ribs, rather than through the periosteum or pericostal soft tissues. Successful diaphragmatic repair was dependent on proper anchoring of the medial border of the prosthesis, placing sutures in the pericardium as necessary. Skin coverage for thoracic cage defects was achieved with widely undermined and advanced local tissue or previously delayed pedicle flaps. All patients had good evidence of chest wall stabilization after operation, and all were removed from mechanical ventilation within three days. One patient died of myocardial infarction twenty days after operation, and a second patient died later of metastatic disease. On the basis of our experience, we conclude that the range of chest wall lesions that can be surgically corrected or palliated is increased by the use of prosthetics implanted with techniques described here.

Thrombotic catastrophe in the patient with multiple Björk-Shiley prostheses.

Thrombosis of the Björk-Shiley prosthesis has been a recognized problem for many years. Review of 172 patients at the University of Kentucky Medical Center who had one or more Björk-Shiley valves inserted between January, 1975, and July, 1980, revealed special problems in those patients with multiple prostheses. Diagnosis and therapy prove more difficult, and the cumulative incidence of thrombosis in the patients with multiple prostheses is 26.8% at six years. Projected long-term use of multiple Björk-Shiley prostheses is discouraged.

The role of thymectomy in red cell aplasia.

Red cell aplasia is an unusual cause of anemia. Fifty percent of all patients with red cell aplasia will have a thymoma. Twenty-five to 30% of those who undergo thymectomy will be cured. Data are presented that suggest that any patient with red cell aplasia should have thymectomy through a median sternotomy. One of 3 such patients who underwent the operation has had complete remission for two years.

Palliation for esophageal carcinoma.

Fifty-three patients with carcinoma of the esophagus treated since 1972 are reviewed. Eighteen unresectable patients with distant metastases or pulmonary insufficiency were treated with irradiation or with esophageal or gastrostomy tubes plus irradiation. There were 5 early deaths, and only 3 patients survived more than three months. Six patients underwent bypass. Three died in the hospital, and 1 lived three months. None compled a course of irradiation or gained weight. The remaining 29 patients, who did not differ clinically from the bypass group, underwent resection for palliation or cure. There were 5 hospital deaths. Twenty patients lived more than three months and 7 of these more than one year. Two of them apparently were cured. These data indicate that the only effective means of increasing the duration of survival for esophageal carcinoma is resection with immediate reconstruction.

Eighteen to 37 hours' preservation of major organs using a new autoperfusion multiorgan preparation.

A new autoperfusion preparation was used to preserve six major organs simultaneously. In 7 Yorkshire white swine, the heart and lungs were separated and removed with the liver, pancreas, duodenum, and both kidneys en bloc while they were self-perfused. Fresh blood, glucose, electrolytes, heparin sodium, methylprednisolone, and a fat emulsion (Soyacal) were infused through the portal vein. No inotropic drugs were necessary. The organs survived for 18 to 37 hours (average survival, 24.6 +/- 2.7 hours [+/- standard error of the mean]). Aortic systolic pressure ranged from 78.5 +/- 5.5 to 98.7 +/- 11.8 mm Hg. Arterial oxygen tension ranged from 206 +/- 23 to 266 +/- 15 mm Hg and arterial carbon dioxide tension, from 20.1 +/- 2.7 to 32.1 +/- 4.9 mm Hg. Blood lactic acid levels decreased from 8.75 +/- 2.06 to 5.50 +/- 2.45 mmol/L at 24 hours. Urine output ranged from 25 to 82 mL/h. Blood urea nitrogen levels decreased from 9.17 +/- 0.59 to 4.67 +/- 1.08 mg/dL. Blood creatinine levels decreased from 1.34 +/- 0.10 to 0.57 +/- 0.22 mg/dL. Serum glutamicoxaloacetic transaminase levels increased from 73.4 +/- 26.3 to 194 +/- 179.5 U/L and serum glutamic-pyruvic transaminase levels, from 44.8 +/- 5.7 to 91 +/- 66.4 U/L. Red blood cell count ranged from 6.94 +/- 0.58 to 13.23 +/- 2.30 x 10(6)/microliters. Lung wet/dry weight ratios changed from 5.79 +/- 0.17 at the beginning to 6.25 +/- 0.16 at 24 hours. The technique for simultaneous multiorgan preservation presented here is simple, effective, and highly reproducible. This study appears to have produced one of the longest average survival times for autoperfusion.

Repair of mycotic aneurysms of the aorta involving the aortic valve.

This report summarizes our successful management of 6 patients who underwent repair of mycotic aneurysms of the ascending aorta within a four-year period. Repairs have been successful despite involvement of as much as two-thirds of the circumference of the aortic valve annulus, involvement of the origin of the right coronary artery, and development of heart block. Three patients required surgical intervention because of hemodynamic decompensation before they had completed antibiotic therapy for endocarditis. In 3 patients, the aneurysm was buttressed with the valve skirt so that aneurysm repair and valve replacement were accomplished in continuity. In 2 patients, the aneurysm was repaired separately and the valve seated on the repair. In 1 patient, a large defect between the left and right coronary arteries was repaired with a woven Dacron patch secured to the valve skirt. The valve was seated to the left ventricle and the graft to the aorta. There were no operative or postoperative deaths. Our data suggest that mycotic aneurysms of the aortic annulus can be successfully repaired despite extensive damage.