Coronary artery bypass surgery in nonagenarians.

As the number of nonagenarians increases yearly in the United States, surgeons will be asked more often to evaluate the possibility of intervention for coronary artery disease in this age group. The purpose of this study is to document experience with patients 90 years of age or older in order to determine whether coronary artery bypass grafting surgery is justified. Eleven patients aged 90 years or more underwent cardiac surgery for symptomatic coronary artery disease refractory to medical management between January 1, 1987, and December 31, 1996. All patients were in NYHA Class IV preoperatively. In-hospital death occurred in two patients (18%). In-hospital morbidity occurred in all patients (100%) including seven cardiac, four respiratory, two neurologic, and one infectious. All survivors left the hospital symptomatically improved. The mean length of stay was 28 days. Four patients died at a mean of 2 years and 2 months postoperatively. Five patients remain alive at a mean of 1 year and 7 months. Coronary artery bypass grafting in nonagenarians can be performed successfully in selected cases. However, increased mortality and morbidity rates and length of stay are associated with this age group. For survivors, the quality of life is improved and the projected life expectancy restored.

Open heart surgery in patients with chronic lymphocytic leukemia.

BACKGROUND: Chronic leukemia is a disease characterized by the malignant proliferation of immunologically incompetent lymphocytes. The knowledge of open heart surgery in patients with this disorder is limited. METHODS: Twelve patients with chronic lymphocytic leukemia underwent open heart surgery (nine coronary artery bypass grafting (CABG), two aortic valve replacement (AVR), one CABG and AVR) from September 1991 to September 1996. There were nine males and three females with a mean age of 68 years (41-81 years). Staging was assigned according to the Rai Classification. There were seven Stage 0, two Stage I, zero Stage II, one Stage III and two Stage IV patients. Cardiopulmonary bypass (CPB) was performed using standard techniques of cannulation, moderate hypothermia and antegrade/retrograde cardioplegia. RESULTS: Hospital mortality occurred in two (17%) patients. Both patients died of sepsis. Hospital morbidity occurred in seven (58%) patients. The most common complications were infections. Five patients were found to have other malignancies (basal cell, laryngeal, prostate, bladder and breast cancers). Transfusion of blood products was required in eight (67%) patients. The average length of stay was 15 days (7-50 days). Follow-up was complete. Late mortality occurred in four patients at a mean of 7 months (1-18 months). All deaths were non-cardiac related (ruptured AAA, kidney failure, respiratory failure and sepsis). Six patients remain alive at a mean of 25 months (1-48 months). CONCLUSION: Hospital mortality and morbidity in patients with chronic lymphocytic leukemia undergoing open heart surgery are high. Infection is the leading cause of hospital death, as well as the most common complication. The majority of patients receive blood products during the course of their hospitalization. Late mortality is high and non-cardiac related. Based on these findings, a re-definition of the aims, goals and expectations of open heart surgery in patients with chronic leukemia is necessary. Suggestions in management are presented.

Pharmacological criteria for ventricular assist device insertion following postcardiotomy shock: experience with the Abiomed BVS system.

BACKGROUND/AIM: The traditional approach to postcardiotomy shock includes inotropic support followed by the application of an intra-aortic balloon pump (IABP). Consideration toward insertion of a ventricular assist device (VAD) becomes necessary when these maneuvers fail to restore hemodynamic stability. The definition of maximal inotropic support, however, is lacking such that a standard formula for VAD insertion remains problematic. The purpose of this paper is to define the pharmacological thresholds for VAD implantation in the setting of postcardiotomy cardiogenic shock. METHODS: The medical records of all adult open-heart operations performed at Hahnemann University Hospital, Philadelphia, PA, from 1 July 1996 through 1 July 1999 were reviewed. Specific data were collected on the hemodynamics and inotrope levels upon separation from cardiopulmonary bypass (CPB). The hospital course was reviewed with attention toward documenting hospital mortality. Cardiogenic shock was defined as systolic blood pressure (SBP) < 100 mmHg, mean pulmonary artery blood pressure (mPAP) > 25 mmHg, central venous pressure (CVP) > 15 mmHg, and cardiac index (CI) < 2.0 L/min/per m2. Inotrope dosages were defined as low, moderate, and high according to assigned values. A formula for VAD insertion was established if cardiogenic shock parameters were present in the setting of two or more high dose inotropes. Early VAD insertion was defined as implantation within three hours of the first attempt to wean from CPB. The VAD recipients were divided into two groups. Group A were VADs placed in conjunction with the formula. Group B was VADs placed in violation (excess) of the formula. The results of these two groups were compared. [table: see text] RESULTS: From 1 July 1996 to 1 July 1999, there were 3462 adult open-heart operations performed at Hahnemann University Hospital, Philadelphia, Pa. The hospital mortality for patients successfully separating from CPB on no inotropes, low-dose, moderate-dose, one high-dose, two high-dose, and three high-dose inotropes were approximately 2.0%, 3.0%, 7.5%, 21%, 42%, and 80% respectively. During this time there were 29 patients supported with the Abiomed BVS (Danvers, Mass) system for postcardiotomy cardiogenic shock. For the entire group of VAD recipients, there were 18 (62%) who were successfully weaned and 8 (28%) who were discharged from the hospital. For the 20 VAD recipients in group A, there were 16 (80%) who were successfully weaned and 8 (40%) who were discharged from the hospital. For the nine VAD recipients in group B, there were two (22%) who were successfully weaned and zero (0%) who were discharged from the hospital. Multiple organ system failure occurred in three (15%) in group A versus seven (78%) in group B patients, respectively. Early VAD insertion was accomplished in 17 (85%) group A patients and 2 (22%) group B patients. CONCLUSIONS: Hospital mortality correlates with the number and level of inotropic support necessary to separate from CPB following adult open heart surgery. The application of a standard pharmacological formula together with hemodynamic criteria for VAD insertion after postcardiotomy cardiogenic shock results in earlier insertion, lower incidence of postoperative MOSF, and improved wean and discharge rates.

Amiodarone-associated hemoptysis.

Amiodarone is a benzofuran derivative with a chemical structure similar to thyroxine. Originally introduced to treat angina pectoris, amiodarone was found to have antiarrhythmic properties, and in 1985, was approved in the United States for treatment of life-threatening ventricular arrhythmias. It is now used for various ventricular and supraventricular arrhythmias refractory to conventional first-line medications, and as a result, side effects have been observed with increased frequency. The most severe and potentially life-threatening of these side effects is the development of pulmonary toxicity. Typically, amiodarone pulmonary toxicity (APT) is manifested by acute pneumonitis and chronic fibrosis. Amiodarone-associated hemoptysis (AAH) is a rare occurrence. The authors describe a case of AAH successfully treated with cessation of drug and steroid therapy.

Postpartum coronary artery dissection: emergency coronary artery bypass with ventricular assist device support.

Acute myocardial infarction during pregnancy and in the puerperium is a rare event: the incidence ranges from 1 per 10,000 to 1 per 30,000 deliveries. Although the etiology is unknown, the pathology may involve thrombosis, spasm, or dissection of the coronary artery. We present the case of a 34-year-old white woman who presented to our institution in cardiogenic shock after an acute myocardial infarction 2 weeks postpartum. This case reinforces the concept that postpartum coronary artery dissection is a fatal disorder. We were able to successfully support the myocardium and the end-organs with a ventricular assist device. We performed concomitant coronary artery bypass grafting in an attempt to salvage the remaining myocardium. Management with emergency coronary revascularization and ventricular assist device support is described.

Total simultaneous repair of coarctation and intracardiac pathology in adult patients.

BACKGROUND: Thoracic aortic coarctation accompanied by a second surgically reparable lesion is a rare combination in the adult patient. The simultaneous operative management of both lesions is desirable because of the higher morbidity and mortality that would occur with staged procedures. METHODS: We describe the simultaneous operative management in three adult patients with coarctation and a second cardiac lesion. All 3 patients had intrapericardial ascending aorta-descending aorta bypass and concomitant repair of a cardiac lesion. The attendant repairs in the 3 patients, respectively, were aortic valve replacement, orthotopic heart transplantation, and coronary artery bypass grafting. RESULTS: Double arterial cannulation, retrograde cardioplegia, large-bore aorto-aortic bypass grafts, and early use of alpha-agonists to stabilize systemic pressure were all key to ensuring safe conduct of the operation. Each patient had an essentially uneventful postoperative course. CONCLUSIONS: Thoracic coarctation and concomitant cardiac pathology can be safely and readily managed with a single-stage approach involving cardiac repair and extraanatomic ascending aorta-descending aorta bypass grafting. A review of the English-language literature of patients managed similarly is included.

Temporary epicardial atrial pacing electrodes: duration of effectiveness based on position.

BACKGROUND: To investigate the duration of effectiveness in the postoperative period of temporary epicardial atrial pacing electrodes on the right atrium, based on position. METHODS: The function of temporary epicardial atrial pacing electrodes were examined in 55 patients undergoing coronary artery bypass grafting from March 20, 1996, to July 31, 1996, at Allegheny University Hospitals, Hahnemann Division, Philadelphia, PA. There were 41 male and 14 female patients. The mean age was 71 years (range 35 to 86 years). Two atrial and two ventricular temporary epicardial pacing electrodes were placed at the termination of cardiopulmonary bypass. One atrial electrode was placed on the body of the right atrium at the junction of the superior vena cava (body electrode); the other was passed through the pursestring of the atrial cannulation site (appendage electrode). RESULTS: The mean thresholds for the atrial body electrodes on the operative day and postoperative days 1 and 2 were 4.96, 6.67, and 6.80 mA, respectively. The mean thresholds for the atrial appendage electrodes were 5.98, 7.50, and 8.59 mA, respectively. CONCLUSIONS: Temporary epicardial atrial pacing electrodes are more effective when the wires are placed in the atrial body of the right atrium than if they are wrapped within the pursestring of the right atrial appendage. As a result of these findings, the common practice of placing the pacing wire through pursestring tissue should be abandoned.

Coronary artery bypass grafting in patients with COPD.

OBJECTIVE: To more fully define the influence of COPD in patients undergoing coronary artery bypass grafting (CABG). METHODS: One hundred ninety-one patients with COPD underwent CABG from March 1, 1995, to June 21, 1996. There were 129 male and 62 female patients. The mean age was 69 years (45 to 86 years). Patients with COPD were defined according to the Summit Database definition: requires therapy for the treatment of chronic pulmonary compromise or has an FEV1 <75% of predicted value. RESULTS: Hospital mortality was 7%. Hospital morbidity was 50%. Statistically significant (p<0.05) morbidity included general pulmonary complications (12%) and atrial fibrillation (27%). Hospital mortality for COPD patients with postoperative pneumonia was 11%. Hospital mortality for patients with COPD receiving steroids was 19%. The hospital mortality for patients > or = 75 years of age was 17%. The combined mortality for patients with COPD who are > or = 75 years of age and receiving steroid therapy was 50%. The mean length of stay was 12 days. Late mortality was 1% at a mean of 1.5 years. CONCLUSIONS: Hospital mortality in most patients with mild-to-moderate COPD undergoing CABG is similar to those without COPD. In the minority of patients with severe COPD who are receiving steroids and > 75 years, the hospital mortality is exceptionally high. These findings support CABG in patients with mild-to-moderate COPD. Nonsurgical therapy should be considered for elderly COPD patients with severe disease taking steroids.

Diagnosis and management of traumatic aorto-right ventricular fistulas.

BACKGROUND: Traumatic aorto-right ventricular (Ao-RV) fistulas are rare lesions that result in congestive heart failure if left untreated. Early diagnosis and prompt surgical intervention are required to avoid the natural outcome of cardiac decompensation. METHODS: All cases of traumatic Ao-RV fistula described in the English literature since 1958 were reviewed. The clinical presentation, methods of diagnosis, and treatment strategies were assessed to determine the pathophysiology, natural history, and outcome of surgical intervention. RESULTS: Forty cases of traumatic Ao-RV fistulas were described in the English literature. There were 39 men and 1 woman, with a mean age of 28.3 years (range, 15 to 50 years). Twenty-two (55%) patients had isolated Ao-RV fistulas. Fourteen (35%) had Ao-RV fistulas with aortic insufficiency. Definitive surgical repair was performed in 38 patients. The associated aortic valve injuries were managed with repair techniques or replacement with prosthetic devices. The surgical outcomes in all patients were satisfactory. CONCLUSIONS: The pathophysiology and natural history of Ao-RV fistulas involves the development of congestive heart failure. Traumatic aortic insufficiency frequently is associated with this disorder. Early diagnosis and prompt treatment are necessary to avoid the natural outcome of cardiac decompensation. Definitive repair should be performed with the aid of cardiopulmonary bypass during the same hospitalization.

Absent pericardium during coronary bypass.

The importance of recognizing congenitally absent left pericardium in the setting of acquired cardiovascular disease was recently appreciated during a case of coronary artery bypass grafting. An associated defect in the left hemidiaphragm and an abnormal location of the left phrenic nerve were found. Careful dissection of the phrenic nerve from the surface of the heart and closure of the diaphragmatic defect were necessary to avoid injury to the former and prevent hernia through the latter structure. Absent left pericardium discovered during cardiac surgery requires attention to the location of the left phrenic nerve and recognition of associated defects in the diaphragm.

Management of infected implantable cardiac defibrillators.

BACKGROUND: The implantable cardiac defibrillator (ICD) was introduced clinically in 1980 for the management of ventricular arrhythmias. METHODS: From January 31, 1989, through May 29, 1996, 329 ICD devices were implanted at Allegheny University Hospital, Hahnemann Division, Philadelphia, Pennsylvania. All device-related infections were examined. RESULTS: Fifteen patients (5%) experienced infection of the generator component of the ICD. There were 14 male and 1 female patients with a mean age of 62 years (range, 38 to 79 years). All infections involved the generator with or without other component involvement. Complete removal of the system was performed in 7 patients, partial removal in 5, and the entire system was left intact in 3. In 4 patients (27%), further procedures were performed to remove additional infection. Three patients (20%) died during the hospital stay. CONCLUSIONS: Infection of ICD devices is a devastating event. We favor complete removal of the ICD generator and all the components when possible. Partial removal of the ICD unit (ie, generator only) is reserved for patients in whom the risk of complete removal is too high and infection is confined to the generator only.

Mycobacterium fortuitum infection of the sternum. Review of the literature and case illustration.

Sternal wound infection with atypical mycobacteria following open heart surgery is a rare occurrence. Previous reports have described infection by Mycobacterium fortuitum, an acid-fast bacillus and member of a larger family of rapidly growing mycobacteria. The source and mode of transmission have not been identified. Surgical debridement and the combination of aminoglycosides and quinolones have been shown to be effective methods of treatment. More recently, clarithromycin has been shown to be the drug of choice against rapidly growing mycobacteria. We describe a 49-year-old woman who underwent infundibular stenosis repair and in whom M fortuitum sternal osteomyelitis developed. Total sternectomy, muscle flap reconstruction, and antibiotic treatment successfully eradicated the infection.

Coronary artery bypass grafting in patients in their third decade of life.

BACKGROUND AND AIM: Coronary artery disease (CAD) and coronary artery bypass grafting (CABG) in young patients are different than their older counterparts. The purpose of this study is to more fully define the issues of CABG in patients in their third decade of life. METHODS: The medical records from all patients under forty years of age undergoing CABG at Allegheny University Hospital, Hahnemann Division, Philadelphia, PA from July 1990 to June 1995 were examined. Surgical outcome, psychosocial, and sexual issues were examined. Lipid analyses were compared perioperatively. RESULTS: There were 43 male and 9 female patients. The mean age was 35 years (23 to 39 years). Risk factors included 43 (83%) patients with a history of smoking, 34 (65%) with familial hypercholesterolemia, 25 (48%) with a family history of CAD, 23 (44%) with hypertension, and 11 (21%) with diabetes. The mean preoperative serum cholesterol was 241 mg/dL. There were no hospital mortalities. Morbidities were found in 18 (35%) patients, including 9 (17%) cardiac, 5 (10%) pulmonary, 3 (6%) infectious, and 1 (2%) renal. In follow-up, three cardiac-related mortalities occurred within five years of surgery. Sixteen patients were readmitted to a hospital for cardiac related causes. Thirty-two (62%) patients failed to return to work, twenty-five (48%) failed to engage in regular exercise, and twenty-four resumed smoking. Psychosocial changes were found postoperatively in thirty (58%) patients. Eight (15%) patients admitted to sexual changes following surgery. Postoperative lipid profiles were minimally altered from preoperative values. CONCLUSIONS: Surgical revascularization is successful in alleviating symptoms with minimal risk. Postoperatively, a number of cardiac related events occurred. A significant number of patients resume smoking, fail to engage in regular exercise, fail to resume work, and fail to take prescribed lipid-lowering agents. Psychosocial and sexual dysfunctions are prominent.

Internal thoracic artery for coronary artery grafting in octogenarians.

BACKGROUND: Use of the left internal thoracic artery as a bypass graft has been shown to result in better long-term patency and improved survival. In elderly patients, the internal thoracic artery has been used less often for coronary artery bypass grafts because of the belief that greater morbidity and mortality are associated with this procedure. This study was undertaken to test this premise in the octogenarian population. METHODS: Over an 8-year period, 474 consecutive patients 80 years of age and greater had coronary artery bypass grafting. The left internal thoracic artery was used in 188 patients (39.7%) (group 1) and saphenous vein grafts only (group 2), in 286 (60.3%). The mean age was 82.6 years (range, 80 to 95 years). There were 312 men (65.8%) and 162 women (34.2%). RESULTS: Use of the internal thoracic artery as a graft has risen steadily each year, as has the number of patients who are octogenarians. The hospital mortality rate was 7.8%. Patients in group 1 had a mortality rate of 9.0% and patients in group 2, a mortality rate of 7.0%. The mortality rate among survivors at 1 year was 6.7%. Long-term survival was significantly greater in group 1. CONCLUSIONS: On the basis of this study, we conclude that the internal thoracic artery is the bypass graft of choice, especially in regard to long-term mortality, and should not be denied to this high-risk group.

Cardiac surgery in nonagenarians.

OBJECTIVES AND BACKGROUND: The purpose of this study was to document our initial experience with patients 90 years of age and older and to determine whether cardiac surgery is justified in this age group. Cardiac surgery in octogenarians has proven to be a successful and worthwhile procedure. A small group of nonagenarians with severe coronary artery disease (CAD) and aortic valve disease refractory to medical therapy have been considered for surgery. METHODS: Fourteen patients aged 90 or more underwent cardiac surgery for symptomatic CAD or aortic valvular disease refractory to medical therapy. Eight patients underwent isolated coronary artery bypass grafting (CABG) and six patients underwent aortic valve replacement (AVR). All patients were in NYHA Class IV preoperatively. RESULTS: Hospital mortality occurred in one patient (7%). Hospital morbidity occurred in 10 patients (71%) and included 7 cardiac, 5 neurological, 1 gastrointestinal, 1 infectious, and 1 pulmonary event. All survivors left the hospital symptomatically improved. The mean length of stay was 26 days. Four CABG patients went on to die at a mean of 2 years and 2 months, and 3 remain alive at a mean of 2 years and 4 months. Three AVR patients expired at a mean of 3 years and 4 months, and 3 remain alive at 4 years and 1 month. CONCLUSIONS: Cardiac surgery in carefully selected nonagenarians is justified and can be performed with acceptable results.

Coronary artery bypass grafting in patients with chronic renal failure: A reappraisal.

BACKGROUND AND AIMS: Chronic renal failure (CRF) is known to increase the morbidity and mortality in patients undergoing cardiac operations. Successful outcome of coronary artery bypass grafting (CABG) in some patients with CRF has been reported, but remains controversial. METHODS: Forty-four patients with CRF who underwent CABG were examined. Two groups were analyzed. Group I consisted of 13 patients with end-stage renal disease on hemodialysis. Group II consisted of 31 patients with a creatinine > or = 1.6 gm/dL for a minimum of 6 months, but were not on dialysis. There were 36 male and 8 female patients, with a mean age of 71 years. RESULTS: The hospital mortality was 10 patients (23%) with 4 (31%) hospital deaths in Group I, and 6 (19%) in Group II. There was major morbidity in 35 (80%) patients. In Group II there were 8 (26%) patients who required permanent postoperative dialysis. A control group of 547 patients 70 years of age who underwent CABG had 30 hospital mortalities (5%) and 75 morbidities (13%). The average length of stay was 27 days. Fifteen patients died at a mean of 34 months after being discharged from the hospital. Nineteen of the original 44 patients remain alive at a mean of 32 months. The total mortality at 6 years and 4 months was 57%. CONCLUSIONS: Older and sicker patients with CRF who undergo CABG are at an exceptionally high risk for mortality and morbidity. For CRF patients not on dialysis with a creatinine 2.5 gm/dL, there is a strong likelihood of permanent postoperative dialysis. Long-term follow-up shows survival to be well below their non-CRF counterparts.

Theoretical and experimental analysis of right ventricular bypass and univentricular circulatory support.

In this paper we examine the dynamic coupling between cardiac pump events and vascular arterial-venous factors that regulate the rate of blood flow around the circulation. A series of experiments were designed to test the feasibility of maintaining vascular and pulmonary function in the absence of the right heart and to characterize the physiologic and hemodynamic consequence of such an exclusion. Theoretical analysis of the cardiovascular system (excluding neuro-humoral factors) using both lumped time invariant and distributed compartmental mathematical equivalent representations, demonstrated that a change in cardiac output (Q) has an inverse-linear effect on venous and direct-linear effect on arterial pressure. A single blood-pump, in a form of a mechanical substitute or the biologic left-heart, alone can support the circulation. Cardiac output reserve is limited (50 percent of normal) because of the rapidly diminishing pulmonary venous-pressure as outflow is increased, irrespective of the pump's specific characteristics. Experiments in animals combined with mock-circulatory studies and computer modeling confirm that near normal flow can be sustained by increasing the stressed blood volume or reducing selectively the systemic venous compliance (i.e., inflatable pressure suit, venous constriction, intra-abdominal compression maneuvers, etc.). The right heart is not essential for normal pulmonary circulation but serves to maintain low systemic venous pressure and relatively high left-heart flow reserve. Purely mechanical properties of the vascular system determine the control and stability of the circulation.

Model-based analysis of transmural vessel impedance and myocardial circulation dynamics.

The basic structure of a model of the coronary circulation has been developed to explain the relationship between transmural perfusion dynamics and intramyocardial mechanics. The model is in the form of a topologically isomorphic network representation and incorporates experimentally measured time-varying perfusion and intramyocardial pressure sources as driving inputs to the model. The intramyocardial vessels are treated as nonlinear impedance elements possessing regional external pressure-dependent resistance and capacitance. Three circuit branches, perfusing the epicardial, subepicardial, and subendocardial muscle layers, are mathematically modeled and are used to predict time-dependent flow within the left ventricular myocardium. The phasic coronary blood flow characteristics predicted by the model exhibit waveform patterns that correlate qualitatively with those patterns measured experimentally. In addition, the pressure-dependent vascular capacitance induces a sustained (out of phase with arterial inflow) venous systolic flow. The model also exhibits retrograde systolic subendocardial flow and stop-flow pressure, which are dependent on coronary resistive and capacitive properties and on the perfusion pressure decay time constant. Furthermore, the results predict an abrupt decrease in subendocardial flow with perturbation of either arteriolar or capillary bed compliance. The model describes time-dependent intramyocardial properties that have been confusing and controversial in the understanding of coronary circulation dynamics. Several steps are identified that are expected to improve and refine the model significantly.