Eric D. Foster

CASS registry: Long term surgical survival

Abstract Objectives To show the effect of clinical, angio and demographic traits on late survival of Coronary Artery Surgery Study (CASS) patients following coronary artery bypass grafting (CABG) and introduce Hazard Function analysis to CASS survival data. Methods Patients were reached by mail survey with 94% response. By National Death Index, vital status was obtained in 99.7% (n = 8221) with a mean follow up of 15 years. Cox proportional hazard and Blackstone Hazard Function regressions were used to assess effects of preoperative traits. Results Ninety percent of patients were alive at 5, 74% at 10 and 56% at 15 years. Of those age 65 and age 75 at operation, 74% and 59% were living at 10 years and 54% and 33% at 15 years (now age 90), survival exceeding the matched U.S. population. Hazard Function falls rapidly after CABG to 9 to 12 months, then rises, doubling by 15 years. Young patients, below age 35, had lower late survival. The time-segmented Cox model (divided at time suggested by the Hazard Function) identified traits showing predictive power early, throughout and late. Female sex, small body surface, ischemic symptoms and emergency status affected survival early. Heavier weight, infarct(s), diuretics, diabetes, smoking, left main and LAD stenosis and use of vein grafts only increased hazard late only. Conclusions There are still lessons from the CASS database. CABG in the elderly is supported by the survival pattern of our patients age 75 at operation. Time-segmented Cox analysis and Hazard Function analysis separate baseline variables into those that predict early mortality and those that predict long survival.

Reoperation for Aortic Coarctation

Reoperation for aortic coarctation has become common because of several factors: (1) increased physician awareness that hypertensive cardiovascular disease continues to threaten the prognosis of the patient following coarctectomy and that investigation in some symptomatic individuals after coarctectomy will demonstrate a residual or recurrent coarctation, even many years after the primary repair; (2) the widespread application of stress testing, which can reveal marked arm-to-leg pressure gradients not observed at rest, to the routine postcoarctectomy follow-up examination; (3) improved noninvasive aortic evaluation techniques, such as ultrasound; and (4) higher salvage rates among infants undergoing urgent coarctation repairs and the recognition that these children subsequently are at high risk for recoarctation. A surgical decision-making process characterized by flexibility provides maximum patient safety; no single reoperation technique can be applied in all situations. Individual circumstances may dictate recoarctation repair by resection with end-to-end anastomosis, tube graft interposition, aortoplasty, or tube graft bypass. The need for a temporary aortic shunt or partial left atriofemoral bypass to maintain adequate distal aortic perfusion pressure during the repair means that these methods must be available at all reoperations. Diligent efforts to repair all hemodynamically significant residual and recurrent coarctations are necessary if the natural fate of premature death is to be avoided for patients with these lesions.

Effect of hemorrhagic shock and reperfusion on the respiratory quotient in swine.

OBJECTIVES Respiratory quotient, the ratio of CO2 production to oxygen consumption (VO2), is principally affected by the fuel source used for aerobic metabolism. Since the respiratory quotient, VO2, and CO2 production cannot be directly measured easily, indirect calorimetry is commonly used to determine the value of these variables at the airway level (i.e., airway respiratory quotient, airway VO2, and airway CO2 production). However, under nonsteady-state conditions, a variety of phenomena can alter the relationship between true metabolic activity and measurements determined by indirect calorimetry. During exercise, for example, airway respiratory quotient increases as anaerobic threshold is reached because of the disproportionate increase in airway CO2 production that results from the CO2 liberated through the buffering of excess hydrogen ions by bicarbonate. We hypothesized that hemorrhage and reinfusion might change airway respiratory quotient in a consistent manner as shock is produced and reversed. DESIGN Prospective laboratory study. SETTING University animal laboratory. SUBJECTS Eight pigs (25 +/- 2 [SD] kg), anesthetized with fentanyl and relaxed with pancuronium bromide, and mechanically ventilated on room air. INTERVENTIONS The animals were sequentially hemorrhaged and then autotransfused while metabolic and hemodynamic measurements were obtained, using continuous indirect calorimetry and continuous applications of the Fick principle. Hemoglobin, arterial lactate concentration, and blood gases for calibration were measured serially. Analysis of variance was used to compare various periods in time. MEASUREMENTS AND MAIN RESULTS Between baseline and peak hemorrhage, and between peak hemorrhage and postreinfusion, all of the following variables changed significantly (p < .05): airway VO2 (baseline 6.4 +/- 0.9 mL/min/kg, peak hemorrhage 3.9 +/- 0.6 mL/min/kg, postreinfusion 7.0 +/- 1.4 mL/min/kg); airway CO2 production (baseline 5.5 +/- 0.9 mL/min/kg, peak hemorrhage 4.5 +/- 0.9 mL/min/kg, postreinfusion 6.0 +/- 1.4 mL/min/kg); airway respiratory quotient (baseline 0.87 +/- 0.07, peak hemorrhage 1.16 +/- 0.07, postreinfusion 0.87 +/- 0.05); lactate concentration (baseline 2.4 +/- 1.2 mmol/L, peak hemorrhage 6.7 +/- 1.9 mmol/L, postreinfusion 5.1 +/- 2.0 mmol/L); and delta PCO2 (venous PCO2-PaCO2) (baseline 4.5 +/- 3.6 torr [0.6 +/- 0.5 kPa], peak hemorrhage 12.1 +/- 5.3 torr [1.6 +/- 0.7 kPa], postreinfusion 2.7 +/- 2.7 torr [0.4 +/- 0.4 kPa]). CONCLUSIONS Airway respiratory quotient increases in hemorrhagic shock and decreases again as shock is reversed during reinfusion. This phenomenon appears related to the buffering of excess of hydrogen ion during hemorrhagic shock.

Vertical axillary thoracotomy: a functional and cosmetically appealing incision.

Vertical axillary thoracotomy offers the specific advantages of minimum trauma and maximum preservation of chest wall function. A cosmetically acceptable scar results. The vertical axillary thoracotomy is specifically indicated in patients requiring less than the maximum intrathoracic exposure provided by the most traumatic posterolateral or anterolateral thoracotomy. The surgical technique is presented.

Cardiac Rhabdomyoma in the Neonate: Surgical Management

Rhabdomyoma is the most common cardiac neoplasm in neonates. Tuberous sclerosis is found in half of the patients with rhabdomyomas. We maintain a surgical policy of accepting for operation only neonates in whom it has been demonstrated that the primary cause for hemodynamic compromise is obstructing, intracavitary neoplasms. Only the intracavitary portions of the rhabdomyoma are excised; no effort is made to completely remove all intramural tumors. Rhabdomyomas demonstrate benign pathological characteristics and may regress. Neonates with rhabdomyomas but no hemodynamic impairment, or those in whom only intramural masses can be demonstrated, are not considered surgical candidates. Tuberous sclerosis by itself should not be judged a contraindication to operation. The results of our surgical policy regarding rhabdomyomas in neonates are reported in two case presentations.

Left ventricular rhabdomyoma causing subaortic stenosis—the two-dimensional echocardiographic appearance

SummaryWe report the preoperative and postoperative clinical findings, M-mode and two-dimensional echocardiograms, and the cardiac catheterization findings in a newborn with left ventricular rhabdomyoma causing severe subaortic stenosis. The tumor was diagnosed by echocardiography at 3 hours of age. The clinical implications of the case are discussed.

Traumatic Aortic Rupture: An Additional Roentgenographic Sign

Esophageal displacement to the right at the level of the aortic arch and isthmus, as marked by an opaque nasoesophageal tube on anteroposterior chest roentgenogram is a useful sign in diagnosing traumatic aortic rupture. Finding this esophageal displacement in patients with blunt chest trauma warrants an immediate thoracic aortogram for demonstration of possible aortic injury.

Anomalous Right Subclavian Artery Arising Proximal to a Postductal Thoracic Aortic Coarctation

Approximately 1% of patients with postductal thoracic aortic coarctation have an associated anomalous right subclavian artery. Previous reports indicated that the aberrant right subclavian vessel arose distal to the coarctation site. The case of a patient is presented in whom the anomalous right subclavian artery originated proximal to the postductal coarctation. We believe this to be among the first reports of this entity. The embryological development pathway and clinical implications of this congenital defect complex are discussed.

Right Heart Reconstruction Following Repair of Tetralogy of Fallot

Ten patients in whom tetralogy of Fallot had been repaired underwent late reconstruction of the outflow tract of the right ventricle because of poor hemodynamic results. The major hemodynamic problems that necessitated right ventricular (RV) outflow tract reconstruction were severe pulmonary insufficiency in 9 patients and pulmonary stenosis in 1. Impaired RV contractility and RV aneurysm were the most important factors prompting valve replacement for severe pulmonary insufficiency. Seven patients received a Hancock prosthesis and 3, an aortic homograft. Among the 7 patients who underwent postoperative cardiac catheterization, the surgical results were hemodynamically excellent in 2, good in 3, and unsatisfactory in 2. The management of pulmonary insufficiency in such patients is discussed.

Disruption of a normal aortic valve as a result of blunt chest trauma.

Many cardiac lesions may result from nonpenetrating chest trauma. Myocardial contusions and lacerations are most common. Isolated valvular lesions are rare. The most common of these, in surviving patients, is aortic valve disruption (12). The course and management of a patient with a torn aortic valve as a result of nonpenetrating trauma are presented. Surgical replacement (porcine) of the valve and stabilization of the fractured sternum were followed by full recovery at 7 months postinjury.