The congenitally cleft posterior mitral valve leaflet. An anticedent to mitral regurgitation

Five patients with isolated congenitally cleft posterior mitral valve leaflets and 1 patient with an associated ostium secundum atrial septal defect are described. The valvular lesion is notable for the constant insertion of normal chordae tendineae into the cleft's free edge and the presence of an additional papillary muscle from which these chordae originate. The clinical presentation varies greatly, and there is no recognized clinical sign that has allowed preoperative diagnosis. The cleft predisposes the valve to significant malfunction in the presence of acquired lesions, thereby necessitating surgical therapy. The choice of procedure to restore mitral competence depends on the degree of valvular and annular disorganization and the associated defects, but the lesion lends itself to successful conservative surgical procedures. Four of the 5 patients with the isolated valve lesion have been successfully treated surgically.     

Intraaortic balloon pumping and emergency coronary arterial revascularization for acute myocardial infarction with impending extension

Seven patients had recurrent pain of myocardial ischemia and impending extension in the recovery phase of acute myocardial infarction. Six had institution of intraaortic balloon pump assistance (IABPA) with subsequent coronary arteriography, and all underwent revascularization. Two patients were in cardiogenic shock (CS), 3 had varying degrees of impairment in left ventricular function, and the remaining 2 were hemodynamically stable. The IABPA interrupted ischemic pain in all patients. Pain recurred in 4 with temporary interruption of IABPA. From one to three vein bypass grafts were constructed in each patient, and in 1 patient, infarctectomy also was carried out. Six of 7 patients recovered and are well. Temporary circulatory assistance with IABP, urgent coronary arteriography, and revascularization was shown to be effective therapy for postinfarction patients with impending extension.     

Chondroma of the Trachea: Report of a Case and Review of the Literature

Chondroma of the trachea is an extremely rare neoplasm. A patient is described who required surgical treatment for this abnormality on three separate occasions over a nineteen-year period. The last two instances represent either local recurrence or new primary growths. The most recent presentation was that of a very large mediastinal mass causing tracheal compression, dysphagia, and superior vena caval obstruction. The clinical and pathological features of chondromas of the tracheobronchial tree are discussed. Because of its recognized potential for local recurrence, a localized chondroma of the trachea is best managed by tracheal resection.     

Esophageal repair following late diagnosis of intrathoracic perforation.

Multiple techniques, often complex, have been used to repair the esophagus following spontaneous, instrumental, or postsurgical perforation, especially when the diagnosis of perforation has been delayed. We have closed such perforations by wrapping a pedicled pleural flap around the esophagus, suturing it firmly over the area of leakage and around its margins. Due to inflammatory changes secondary to perforation, the flap is thickened and easily applied. Four patients were treated with this technique with success in every case. One patient with achalasia had sustained perforation three days prior to repair, another 30 hours following leakage at an esophageal suture line, the third 20 hours following esophagoscopic extraction of a necrosing foreign body, and the fourth 8 hours following hydrostatic bougienage for achalasia.     

Survival following free rupture of left ventricular aneurysm: report of a case.

A 50-year-old man sustained free rupture of the left ventricle four weeks following a massive anterior myocardial infarction. The rupture occurred at the junction between a bulging left ventricular aneurysm that was not yet fibrotic and normal myocardium without evidence of fresh myocardial infarction. Accurate preoperative diagnosis aided by echocardiography and right heart catheterization made possible a planned surgical approach. Postoperative support with intraaortic balloon pumping appeared to be beneficial in maintaining statisfactory cardiac function until an adequate stroke volume could be reestablished, presumably by an increase in left ventricular volume.     

Plasma Vasopressin Levels and Urinary Sodium Excretion during Cardiopulmonary Bypass with and without Pulsatile Flow

The use of pulsatile perfusion during bypass should create a more physiological milieu and thus attenuate the vasopressin stress response. To determine this, 20 patients scheduled for elective coronary artery bypass operation were studied in two groups. Group 1 had standard nonpulsatile perfusion, and in Group 2 a pulsatile pump was used. Measurements were made before and after anesthesia, after surgical incision, and at 15 and 30 minutes during and after cardiopulmonary bypass.In both groups, vasopressin levels were significantly elevated after sternotomy (4.5 ± 1.5 to 37 ± 10 pg/ml in Group 1 and 3.1 ± 1.2 to 33 ± 9 pg/ml in Group 2, p < 0.05) and during bypass (198 ± 19 pg/ml in Group 1 and 113 ± 16 pg/ml in Group 2) but were higher in Group 1 (p < 0.05). With comparable perfusion pressures in both groups, Group 2 required higher flow (4.5 ± 0.2 versus 3.5 ± 0.3 L/min, p < 0.05) and had lower resistance (1,351 ± 182 versus 1,841 ± 229 dynes sec cm^-5, p < 0.05) and higher urine Na⁺ (123 ± 5 versus 101 ± 8 mEq/L, p < 0.05). These data demonstrate that pulsatile flow can significantly attenuate the vasopressin stress response to bypass. Since vasopressin, at these concentrations, is a potent vasoconstrictor and is capable of producing a Na⁺ diuresis, this may partially explain the higher flow requirements and the decrease in Na⁺ excretion.     

Correlation of Patterns of Subendocardial Reperfusion and Left Ventricular Performance after Ischemia

Ninety-three dogs were studied with normothermic or hypothermic ischemia for 60 or 90 minutes, with or without potassium cardioplegia. Radioactive-labeled microspheres (9 ± 1) were injected into the aortic perfusion cannula just prior to aortic cross-clamping and at 2, 6, and 10 minutes after the clamp was released. Left ventricular (LV) function was analyzed with a right heart bypass model before and 45 minutes after the ischemia period. Changes in LV function were defined as the arithmetic difference in the center of mass between preischemia and postischemia computer-drawn Sarnoff curves.Regardless of technique of myocardial protection, increased subendocardial flow 2 minutes after ischemia correlated strongly with preservation of LV function (p < 0.01). Well-preserved hearts showed a rapid return to normal levels of coronary blood flow (p < 0.01). In contrast, a delay in the peaking of subendocardial flow to 10 minutes was associated with poor function (p < 0.01). There was a high correlation between ultrastructural morphology and LV function. While well-preserved hearts show early preferential subendocardial perfusion, the poorly protected myocardium is unable to restore adequate subendocardial flow early in the reperfusion period.     

Tracheal tumors: surgical management.

In a 15-year period, 63 patients with primary tracheal tumors were seen. Twenty-eight patients with primary tumors and 8 with secondary tumors of the trachea were treated by resection with single-stage reconstruction. There were 24 cylindrical resections of trachea, 2 lateral resections of trachea, and 10 carinal reconstructions. Thirty-five additional patients with primary tracheal tumors were managed by staged reconstruction, irradiation, or no treatment. The most common primary lesion was squamous cell carcinoma and the second, adenoid cystic carcinoma. Benign primary tumors and low-grade malignant tumors obtained excellent palliation and usually cure. Surgical removal of squamous cell carcinoma and adenoid cystic carcinoma, usually with adjunctive irradiation, provided good palliation or the probability of cure. Resection of selected secondary tumors provided long-term palliation.     

Effects of continuous nitroglycerin infusion on acute myocardial ischemia in dogs

The effects of a continuous infusion of nitroglycerin (NTG) were evaluated by hemodynamic measurements and measurements of regional myocardial blood flow (RMBF) in dogs on right heart bypass with left anterior descending coronary artery ligation. NTG infusion which decreased afterload, mean aortic pressure (MAP) decreased from 100 to 85 mm Hg, thus also decreasing coronary perfusion pressure) resulted in an 11.8% increase in total coronary blood flow (CBF), a 19.1% decrease in coronary vascular resistance index (CVRI), and a 21.7% decrease in myocardial oxygen consumption (MV?O₂). When MAP was returned to the control level (100 mm Hg) with continuing infusion of NTG, CBF increased 49.1%, and CVRI decreased by 23.4% compared to the pre-NTG ischemic state. Regional myocardial blood flow (microsphere technique) to ischemic tissue at the border of the infarct remained stable with NTG infusion despite decreased MAP, in contrast to the significant fall in RMBF in this region with decreased MAP in the control group without NTG. When MAP was elevated back to pre-NTG levels, an 18.6% increase in RMBF to the border of the infarct was seen compared to an insignificant change in RMBF in untreated (control) animals. These data are consistent with the concept that under conditions of regional myocardial ischemia, coronary blood flow to the “border zone” (ischemic myocardium) is maintained or enhanced by NTG, even when coronary perfusion pressure is modestly reduced.     

Mitral valve replacement: a nine-year follow-up of risks and survivals.

Experience with mitral valve replacement over a nine-year period is reviewed. Hospital mortality was 8.9%, with an additional late mortality of 18.5% during a mean follow-up period of 4.34 years. Study of the factors influencing the results of valve replacement revealed a direct correlation between long-term survival and New York Heart Association (NYHA) Functional Class, as judged preoperatively, as well as left ventricular end-diastolic pressure, cardiac index, type of valve lesion, and presence of associated coronary artery disease. Hospital mortality was 32% (p less than 0.01) for those patients in NYHA Functional Class IV before operation, compared with 3% for Class III patients. Untreated concomitant coronary artery disease was associated with a significantly higher perioperative mortality of 28% (p = 0.002) compared with an 8% mortality in patients with coronary artery disease treated by vein bypass at the time of mitral valve replacement. Patients with normal coronary arteries documented angiographically before operation had a 1% hospital mortality. Seventy-two percent of all patients are still alive at a maximum follow-up of nine years. Eighty-three percent of those survivors who were in Functional Class III or IV before operation are now considered to be in Class I or II. We conclude that patients should undergo mitral valve replacement before the development of the advanced functional stage of valve disease. In addition, coronary arteriograms should be performed on all patients who are more than 40 years old at the time of cardiac catheterization, and revascularization considered at the time of mitral valve replacement for those patients with significant coronary disease.     

Extended Evaluation of Effects of Anoxia on Ventricular Performance and Compliance

Eight dogs were prepared by implanting a left ventricular pressure transducer, aortic flow probe, and endocardial ultrasound crystals across the maximum transverse left ventricular diameter. In an unanesthetized state, the dogs were evaluated at rest and with acute volume loading, both before ischemic cardiac arrest and sequentially (2, 4, 6, 12, 24, and 48 hours) after 20 minutes of arrest during normothermic cardiopulmonary bypass.At a left ventricular end-diastolic diameter comparable to preoperative levels, left ventricular systolic pressure, heart rate, and rate of rise of left ventricular pressure were not changed, but at 2 to 6 hours there was a significant decrease in cardiac output (p < 0.01), left ventricular stroke work (p < 0.01), ejection fraction (p < 0.05), maximum rate of systolic diameter shortening (p < 0.05), and circumferential fiber shortening (p < 0.05). They gradually returned to control levels by 24 hours postoperatively. Left ventricular compliance, as measured by left ventricular end-diastolic pressure at a set end-diastolic diameter and by left ventricular diastolic pressure/diameter, was reduced at 2 hours (p < 0.01) and gradually returned to control values at 48 hours. Thus, reversible myocardial injury due to anoxia is associated with both decreased contractility and compliance, with resultant depressed left ventricular performance for 24 to 48 hours after injury.     

The Effect of Hemodilution with Albumin or Ringer's Lactate on Water Balance and Blood Use in Open-Heart Surgery

To determine the effect of intraoperative albumin administration on blood use, water balance, and postoperative clinical course, we studied two groups of adult cardiac surgical patients. Group I (30 patients) received 25 gm of albumin during withdrawal of 2 units of blood prior to cardiopulmonary bypass (CPB) and 50 gm of albumin in the oxygenator prime. Group II (32 patients) received no albumin prior to the end of CPB. No difference in clinical course could be identified, nor was there a significant difference in blood use. Group I patients had lower hematocrit values intraoperatively from the time of blood withdrawal until the conclusion of operation. Coronary artery bypass operations were associated with greater positive water balance than were heart valve operations. Forty-three percent of the patients having coronary artery bypass grafting had a positive water balance greater than 5 liters, whereas 50% of those undergoing valve procedures had a balance less than 3 liters. We conclude that the principal effect of withholding albumin under these circumstances is to increase net positive water balance. The greater positive water balance does not appear to be detrimental.     

Primary Reconstruction of Airway after Resection of Subglottic Laryngeal and Upper Tracheal Stenosis

Eighteen patients with low subglottic laryngeal stenosis and upper tracheal stenosis underwent resection of the anterior and lateral cricoid cartilage and upper trachea with reconstruction by primary laryngotracheal anastomosis. The posterior cricoid plate and recurrent laryngeal nerves were preserved. The distal trachea was tailored obliquely with an anterior prow and was anastomosed to the thyroid cartilage anteriorly and to the residual cricoid posteriorly. Where the stenosis was circumferential, scarred mucosa was resected from the anterior surface of the posterior cricoid lamina and the defect covered with a tailored flap of membranous tracheal wall.In 14 patients the lesions followed intubation injury. In 2 the stenosis was idiopathic. One stenosis resulted from inhalation burn and one from localized amyloidosis. Many patients had undergone previous surgical repairs.Sixteen patients had good to excellent results from six months to five and one-half years later. Reconstruction of the burned airway failed. One additional patient is still under treatment with a T tube.     

Acute Traumatic Disruption of the Thoracic Aorta: A Ten-Year Experience

During a ten-year period, 44 patients were treated for acute traumatic disruption of the thoracic aorta. Of the 44 patients, 21 had operative repair within 48 hours of injury (Group 1); 14 patients had operative therapy electively delayed for 2 to 79 days (Group 2); 5 had operative therapy electively delayed indefinitely (Group 3); 2 had immediate operative repair when a delayed diagnosis was made at 21 and 56 days, respectively (Group 4); 1 patient died during angiography and 1 refused operation (Group 5). Mortality was as follows: Group 1, 24%; Group 2, 14%; Group 3, 0; Group 4, 100%; and Group 5, 100%. All operative deaths occurred in the subgroup of 23 patients in whom left heart bypass was utilized.Immediate operative intervention with a heparinized shunt is preferable as soon as the diagnosis of thoracic aortic disruption has been established, but elective delay of operation in patients with severe concomitant injuries can be achieved safely with beta blockade and antihypertensive therapy.     

Myocardial oxygen consumption with isoproterenol versus calcium chloride in hypocalcemic ventricular failure in dogs

In 30 dogs on right heart bypass we compared the effects of isoproterenol with those of calcium chloride on myocardial oxygen consumption and on left ventricular function in the setting of ventricular depression produced by ionized hypocalcemia. In 22 dogs (Groups A and B) either isoproterenol or calcium chloride was infused, left ventricular function curves were generated, and end-diastolic pressure vs segment length plots were obtained. In 8 dogs (Group C), with initial hypocalcemia, both isoproterenol and calcium chloride were infused separately in random order to produce an equal decrease in left ventricular end-diastolic pressure at constant mean aortic pressure, heart rate, and cardiac output. Myocardial oxygen consumption and indices of left ventricular function were obtained. In Groups A and B, both drugs, when administered to the ventricle depressed by hypocalcemia, displaced left ventricular function curves upward and to the left. Left ventricular stroke work at constant left ventricular end-diastolic pressure increased (from 13.0 +/- 1.3 to 31.2 +/- 2.3 g X m for isoproterenol; from 13.9 +/- 2.5 to 32.5 +/- 2.5 g X m for calcium chloride). In Group C, there were no significant differences between left ventricular end-diastolic pressure, end-diastolic internal diameter, myocardial oxygen consumption, or peak left ventricular dP/dt in the hypocalcemic periods preceding isoproterenol and calcium chloride infusion. When the two drugs caused matched decreases in left ventricular end-diastolic pressure (-7.4 +/- 0.5 cm H2O for isoproterenol; -7.3 +/- 0.8 cm H2O for calcium chloride) there were similar decreases in end-diastolic internal diameter. However, isoproterenol was associated with a significantly greater (P less than 0.001) myocardial oxygen consumption (13.7 +/- 0.4 ml X 100 g-1 X min-1) than calcium chloride infusion (11.9 +/- 0.4 ml X 100 g-1 X min-1), as well as a greater peak left ventricular dP/dt (P less than 0.005).     

Regional Myocardial Protection during Aortic Cross-clamp Ischemia in Dogs: Calcium-Containing Crystalloid Solutions

To study the effects of calcium in cardioplegic solutions, an in situ dog heart model was used that allowed infusion of two different cardioplegic solutions into separate regions of the same heart. Two concentrations of ionized calcium, 1.0 mM and 0.5 mM, in a cold, potassium-containing solution were tested in two groups of dogs and compared with the same cold, potassium-containing solution but without the calcium, during 100 minutes of global myocardial ischemia induced by aortic clamping. Results were evaluated in terms of percent change of regional systolic shortening measured with ultrasonic piezoelectric crystals, percent change of regional myocardial blood flow, and change of regional left ventricular myocardial diastolic distensibility. No significant differences were found between myocardial regions protected with calcium of either concentration and regions protected without calcium. This study could demonstrate no beneficial or adverse effects of including calcium in this type of crystalloid cardioplegic solution applied to an in situ dog heart model.     

Carinal Reconstruction

Thirty-six carinal resections were performed: 23 for primary neoplasms of the airways, 5 for bronchogenic neoplasms, and 8 for inflammatory lesions. In 31 cases, primary reconstruction was done. Eleven reconstructions were performed without pulmonary resection; in 5, right upper lobectomy was also done, in 9 pneumonectomy, and 6 patients had had a prior left pneumonectomy. Five staged reconstructions were attempted.The mode of reconstruction depended on the precise location and extent of the lesion. Bronchial anastomoses to the side and end of the trachea or to the end of the trachea and to the side of a bronchus predominated. Four deaths occurred among the 31 patients who had primary reconstruction (13%). Two patients with anastomotic stenoses had successful reexcision. Attempts at staged reconstruction failed.     

Repair of Inflammatory Tracheoesophageal Fistula

Benign acquired tracheoesophageal fistula is uncommon. Erosion of the membranous wall of the trachea and the anterior esophageal wall by the high-pressure cuff on a tracheostomy tube, often against the anvil of a nasogastric tube, may produce such fistulas. Techniques for closure have included patching the tracheal defect with muscle and, often, multiple staged procedures, planned or unplanned.Since any cuff lesion severe enough to cause a fistula necessarily damages the trachea circumferentially at the same level, definitive correction must include circumferential tracheal resection as well as closure of the fistula. Five patients with tracheoesophageal fistula due to cuff perforation had repair by such a single-stage procedure. Through an anterior approach the involved trachea was resected, primary anastomosis was done, and the esophagus was closed in layers. In 3 of these 5 patients muscle was interposed for added security. One patient had undergone a prior attempt at repair elsewhere. One required a second resection of trachea for subsequent stomal stenosis. Repair in 2 additional patients with fistulas of complex origin related to direct trauma, sepsis, and foreign body involved adaptation of the basic technique to the special problem; 1 of these procedures was necessarily staged. Results in all 7 patients have been good.     

Esophageal Perforation

Esophageal perforation can be caused by any instrument, device, or foreign body reaching the hypopharynx. Diagnosis remains difficult. If esophageal perforation is suspected, Gastrografin (meglucamine diatrizoate) swallow study, eventually followed by barium swallow study, is the most useful diagnostic test. Absolute rules cannot be made about the selection of nonoperative or surgical treatment. If diagnosed early, cervical or thoracic esophageal perforations can sometimes be treated conservatively if there are no signs of systemic sepsis. Recurrent leakage after surgical closure is not unusual. Local tissue flaps can reinforce the closure, particularly after delayed operation, thereby often avoiding the necessity for a reoperation or an esophageal exclusion.