Pulmonary hypertension secondary to neurofibromatosis: intimal fibrosis versus thromboembolism.

Neurofibromatosis has been known to involve blood vessels throughout the body. Pulmonary involvement with interstitial fibrosing alveolitis has been described but no case of pulmonary vascular involvement has been reported to date. A 51 year old patient with cutaneous neurofibromatosis is described who presented with severe pulmonary hypertension and radiographic, scintigraphic, and angiographic evidence of chronic thromboembolic pulmonary hypertension. Severe intimal fibrosis consistent with vascular involvement with neurofibromatosis was found on endarterectomy with no evidence of pulmonary thromboembolism. Neurofibromatosis of pulmonary arteries should be considered as a possible cause of pulmonary hypertension.

Coronary Artery Bypass Grafting without Cardiopulmonary Bypass: Improvement in Cardiac Function Following Enflurane Anaesthesia during Coronary Occlusion.

Severe adverse effects, especially neurologic complications after cardiopulmonary bypass have lead to the development of techniques for performing coronary artery bypass graft surgery without cardiopulmonary bypass. Laboratory and clinical studies confirmed the positive role of enflurane anaesthesia in preventing myocardial dysfunction following an ischaemic interval. The aim of this study was to evaluate the haemodynamic response to enflurane anaesthesia during single graft coronary bypass surgery without cardiopulmonary bypass. Twenty one patients were divided randomly into two groups: control and enflurane groups. Haemodynamic parameters and those derived from a pulmonary artery catheter were recorded and analysed. In the enflurane group, the amount of fentanyl administered was considerably less than in the control group: 25.7 +/- 3.8 microg/kg vs 36.8 +/- 1.6; p=0.03. The mean arterial pressure during enflurane administration was lower than in control group, but the difference was not significant. Despite a dearease in left ventricular function during the performance of the anastomosis in the enflurane group, a significant recovery was noted after 20 minutes of reperfusion: cardiac index increased from 1.4 +/- 0.1 to 1.85 +/- 0.1 L/min/m2 and left ventricular stroke work index from 15.8 +/- 1.1 to 27.7 +/- 6.7 g.m.m2 . In the control group, the deterioration in cardiac function observed during the graft anastomosis did not recover till the end of the surgical procedure. We conclude that enflurane anaesthesia may be a positive addition to fentanyl-based anaesthesia by improving myocardial function following CABG without bypass surgery.

Estrogen induces nitric oxide-mediated vasodilation of human mammary arteries in vitro.

Human internal mammary arteries (IMA) are relatively protected from atherosclerosis. Estrogen plays a protective role in cardiovascular disease. It causes in vitro and in vivo vasodilatation, but the mechanisms are contradictory. To investigate the in vitro vasomotor effect of estrogen on IMA and the role of endothelium, we studied 30 IMA segments harvested from 10 men during coronary artery bypass grafting surgery. Patients with diabetes mellitus, hypercholesterolemia, hypertension, and smoking were excluded. Twenty IMA rings had intact endothelium ((+)Endo) and 10 rings were denuded of endothelium ((-)Endo). Vasomotor response of each ring was expressed as the percentage of maximal response to norepinephrine (NE). Acetylcholine (10(-8)-10(-5) M) given to (+)Endo and (-)Endo rings induced vasorelaxation of 72 +/- 30.4% and vasoconstriction of 48.5 +/- 20.1%, respectively. 17-Beta-estradiol (10(-8)-10(-5) M) given after maximal precontraction with NE induced marked relaxation in (+)Endo (80.9 +/- 39.2%), but no significant vasomotor effect in (-)Endo rings (P < 0.0001). Vasorelaxation to 17-beta-estradiol (10(-6) M) in (+)Endo rings was 64.5 +/- 18.4 and 8.6 +/- 8.4%, before and after 15-min treatment with nitric oxide synthase inhibitor, L-nitroarginine methyl ester, respectively (n = 14, P < 0.0001). Tamoxifen (10(-6) M) decreased 17-beta-estradiol (10(-7) M)-induced relaxation by 71%. In conclusion, 17-beta-estradiol induces endothelium-dependent NO-mediated vasodilation of human mammary arteries in vitro. This response is mediated through estrogen receptors.

Cerebral protection using retrograde cerebral perfusion during hypothermic circulatory arrest.

BACKGROUND: Retrograde cerebral perfusion through the superior vena cava (SVC) has been proposed to protect the brain from ischaemic injury during profound hypothermic circulatory arrest (PHCA). Its contribution to cerebral protection is unclear. Furthermore, the addition of anaesthetic or vasodilating agents to the SVC perfusate to enhance brain protection, has never been described. METHODS: In three patients undergoing repair of the ascending aorta utilizing PHCA, the upper body was retrogradely perfused with cold (16 degrees C) blood through the SVC by the cardiopulmonary bypass pump. Electroencephalographic activity was monitored using a computerized electroencephalographic monitor (Cerebro Trac 2500, SRD). Perfusion pressure was measured at a port in the cannula connector. Etomidate or thiopentone was injected into the SVC perfusate to arrest reappearing electroencephalographic activity. Nitroglycerin or nitroprusside was injected into the perfusate to increase retrograde flow and maintain a constant perfusion pressure. RESULTS: During PHCA periods of up to 61 min, recurrent electroencephalographic activity was abolished by the retrograde administration of small boluses of etomidate (total 50 mg) or thiopentone (total 500 mg). Nitroprusside (100 micrograms) and nitroglycerin (2 micrograms.kg-1.min-1) increased retrograde flow from 220 to 550 and 660 ml.min-1, respectively, while maintaining perfusion pressure (25-26 mmHg). Recovery from anaesthesia and surgery was uneventful, with no adverse neurological sequelae. CONCLUSION: Injection of anaesthetic agents into the retrograde SVC perfusate during PHCA, can suppress reoccurring electroencephalographic activity and retrograde injection of vasodilators can facilitate an increase in perfusion. It is suggested that both may augment brain protection.

[Pulmonary thrombo-endarterectomy].

Chronic pulmonary thromboembolism is an underdiagnosed condition with major morbidity and mortality. Over the past year and a half, we diagnosed 6 new cases of which 3 underwent successful, pulmonary thrombo-endarterectomy (2 in San Diego, 1 in Jerusalem). All recovered fully and returned to normal, active life. We conclude that pulmonary thrombo-endarterectomy is a viable option for patients with chronic pulmonary thromboembolism.

Left ventricular free wall rupture as the presenting manifestation of acute myocardial infarction in diabetic patients.

We present 5 diabetic patients with acute myocardial infarction in whom left ventricular free wall rupture was the presenting manifestation. Echocardiography may be indicated in diabetic patients with acute myocardial infarction and in shock, prior to thrombolysis.

[Treatment of concomitant coronary and carotid disease].

The optimal surgical treatment for concomitant carotid and coronary artery disease is controversial. Between 1991 and 1995 we performed 34 procedures for combined disease of the carotid and coronary arteries. The first 8 operations were carotid endarterectomies followed by coronary artery bypass grafting (staged procedure). The next 26 operations were performed during a single anesthesia (combined procedure). The patients were 28 men and 6 women, aged 58-81 years (mean 68). 80% were in functional class III or IV. In 40% ventricular function was moderately or severely reduced. There was an average of 3.6 grafts per patient, and in all except 3 patients the left internal thoracic artery was used as a conduit for coronary artery bypass grafting. 30% had symptomatic carotid stenosis; there was no perioperative mortality. In the staged procedure group, 2 patients had postoperative cardiac complications: in 1 acute coronary insufficiency and acute myocardial infarction in the other. 1 had postoperative, transient, amaurosis fugax. In the combined procedure group, 1 had a myocardial infarction and 1 a minor occipital stroke. During follow-up, 1 patient died 4 months after operation of myocardial infarction, and 1 had a minor stroke. The results suggest that the combined procedure is safe and carries low risk of both mortality and morbidity. Whenever cardiac disease is stable and there is no main coronary artery disease, a staged procedure should be considered. In any other situation we continue to perform the combined procedure.

[Aortopulmonary window: influence of associated cardiovascular lesions on surgical management].

Aortopulmonary (AP) window is an uncommon cardiac anomaly which is frequently associated with other cardiac anomalies. Concomitant repair of all intra- and extracardiac anomalies is usually recommended. Between October 1993 and July 1994, 4 patients aged 37 days, 4 weeks, 3.5 and 1.5 years, respectively, underwent repair of AP window and associated malformations. The associated anomalies consisted of interrupted aortic arch (IAA), and atrial and ventricular septal defects in the 1st patient, patent ductus arteriosus in the 2nd, inlet ventricular septal defect in the 3rd and congenital narrowing of the right pulmonary artery and a patent foramen ovale in the 4th. Extreme metabolic acidosis after repair of IAA in the 1st, dictated ligation of the AP window before repair of the intracardiac anomalies at 2 months of age. In the 2nd and 3rd, repair of the window and associated anomalies was performed in a single stage. In the 4th, left pulmonary artery banding preceded complete repair. All patients are doing well at 18, 13, 12 and 11 months, respectively, of follow-up after their last operation. Surgical management of AP window may have to be staged according to the physiological influence of the associated anomalies in each patient, to minimize the cumulative risk of complete repair.

Normothermic continuous blood cardioplegia improves electrophysiologic recovery after open heart surgery.

BACKGROUND: Myocardial protection during open heart surgery is based on administration of oxygenated blood cardioplegia, the preferred temperature of which is still under debate. The current randomized study was designed to prospectively evaluate the quality of myocardial protection and the functional recovery of the heart with either normothermic (group N) or hypothermic (group H) oxygenated blood cardioplegia. METHODS: Under continuous electrocardiographic Holter monitoring, 42 patients were randomly scheduled to receive either normothermic (33.5 degrees C) or hypothermic (10 degrees C) cardioplegia solutions during coronary bypass grafting surgery. Blood samples for creatinine phosphokinase, creatinine phosphokinase-MB, lactate, epinephrine, and norepinephrine were withdrawn during cardiopulmonary bypass via a coronary sinus cannula. RESULTS: Active cooling in group H on initiation of cardiopulmonary bypass was characterized by transition through ventricular fibrillation in 75% of patients, whereas in group N atrial fibrillation occurred in 65% of patients. On myocardial reperfusion, sinus rhythm spontaneously resumed in 95% of group N patients compared to 25% in group H (P = 0.0003). In the latter, 75% of patients developed ventricular fibrillation often followed by complete atrioventricular block, which necessitated temporary pacing for a mean duration of 168 +/- 32 min. Both groups showed a similar incidence of intraventricular block and ST segment changes. However, the incidence of ventricular premature beats in the first 16 h after cardiopulmonary bypass was significantly greater in group H (P < 0.05), 20 +/- 26/h, compared to 3 +/- 5/h in group N. Blood concentrations of lactate, creatinine phosphokinase, epinephrine, and norepinephrine increased gradually during the operation, but the differences between the groups were not significant. CONCLUSIONS: The current prospective human study suggests that the increased susceptibility for ventricular fibrillation and dysrhythmia, and the delayed recovery of the conduction system after hypothermic myocardial protection, are related to temperature-induced changes in vital cellular functions of the conduction tissue in the postischemic period. Both cardioplegic methods provide adequate myocardial protection but normothermic oxygenated blood cardioplegia may accelerate recovery of the heart after cardiopulmonary bypass.

Early experience in lung transplantation.

Lung transplantation is becoming an acceptable mode of therapy worldwide for the end-stage lung disease. We present our initial experience with the first 10 consecutive lung transplant patients at Hadassah University Hospital. There were 5 males and 5 females with an age range 27 to 59 years. Eight patients underwent single lung transplantation, one patient had double lung transplantation and one had heart-lung transplantation. Indications were: pulmonary fibrosis in 4, emphysema in 4, cystic fibrosis in 1, and cystic bronchiectasis in 1. Two patients had primary graft failure (1 death). Nine patients had a serious infection after transplantation (1 death). Four patients developed airway complications including dehiscence of bronchial anastomosis (1 death), bronchial stenosis requiring placement of a stent in 2 patients, and pneumothorax in 1 patient. One patient required tracheostomy. One patient died of massive brain infarction secondary to pulmonary venous thrombosis and embolization. Six patients are intermediate-term survivors, with a follow-up period of 4-24 months. Four of them had at least one episode of rejection each. In all survivors pulmonary functions and quality of life improved and they do not need supplemental oxygen. We conclude that lung transplantation is a viable option for end-stage lung disease. Better selection of patients and perhaps improved immunosuppression agents will further improve outcome in lung transplantation. Shortage of donor supply is currently the limiting factor in successful lung transplantation in Israel.

[Successful single-lung transplantation in emphysema].

Lung transplantation is now considered acceptable therapy for end-stage lung disease. Until recently therapy for emphysema was disappointing, but lung transplantation has brought new hope for those terminally ill with the disease. We present our early experience with single-lung transplantation in 5 men and 1 woman with emphysema, 40-61 years old. All recovered following surgery, with remarkable improvement in lung function and functional capacity. They are now 6-20 months post-transplantation, do not need oxygen supplementation and are able to perform their normal daily activities. Shortage of donor organs is the limiting factor for single-lung transplantation in these patients.

Luke warm blood cardioplegia for CAB surgery in patients with severely impaired LV function. Improved results.

Ward blood cardioplegia (WBC) has recently been reported to improve myocardial protection in adult open heart surgery, especially in high risk cases. However, WBC has been reported to have some disadvantages including narrow safety margins concerning brain and kidney perfusion. We therefore modified our technique to utilize luke-warm blood cardioplegia (LWBC). We carried out 470 open heart procedures using luke-warm cardioplegia (anterograde + retrograde perfusion) from 1/2/1991 - 30/9/1992; 94 had LVEF < 30% and form the basis of this study. Other major risk factors in this group included: > 70 yrs - 26 patients, L main > 50% - 14 patients, emergencies - 11 patients, redo's - 3 patients. Eightyone patients underwent CAB only; 3 had additional MVR, 3 additional closure acute VSD of whom one underwent additional LV aneurysmectomy, one additional AVR; 4 patients underwent AVR only, and 2 MVR. Average number of grafts/patient for the 81 isolated CAB's was 4.5. IABP was necessary postbypass in 4 patients (9 emergencies were on IABP support at time of operation). Thirty day mortality was 3 patients (3.2%). Late mortality was 5 cases. These results are superior to those achieved using cold protection and warm blood cardioplegia. LWBC is a safe method for myocardial protection in patients undergoing CAB, particularly when LV function is severely compromised.

Tetralogy of Fallot, absent pulmonary valve, partial anomalous pulmonary venous return and coarctation of the aorta.

We describe a unique combination of tetralogy of Fallot, absent pulmonary valve, aortic coarctation with partial anomalous pulmonary venous connection and a retroaortic innominate vein. Surgical repair was successfully accomplished in two stages: coarctation repair preceded correction of the intracardiac anomalies.

[Endobronchial stenting in bronchial stenosis following lung transplantation].

Endobronchial stricture is not an uncommon complication following lung transplantation and may cause significant morbidity and mortality. We report our experience in a 36-year-old woman and a 39-year-old man who underwent lung transplantation and developed stenosis in the anastomotic area. Implantation of a silicone stent in 1 patient and an expandable metal stent in the other were successful. Both patients developed infections with Aspergillus fumigatus, 1 of whom died of fungal dissemination.

Aorto-atrial fistula following internal jugular vein catheterization.

A 48-year-old woman with giant haemangioma of the liver underwent percutaneous transjugular placement of a stent in the left hepatic vein for relief of an obstruction due to the compression of the benign liver tumour. Following the procedure, paroxysmal atrial fibrillation occurred and right-sided heart failure gradually appeared. Echocardiography and cardiac catheterization demonstrated a fistula between the aortic root and the right atrium, that was confirmed on surgery.

Warm continuous antegrade blood cardioplegia: applications in congenital heart disease.

UNLABELLED: Continuous warm blood cardioplegia is utilized by many surgeons as their method of choice for myocardial protection during operations for acquired heart disease. OBJECTIVE: this study was performed to determine the feasibility and safety of this method for intracardiac procedures through the right atrium and in particular, total cavopulmonary connection. MATERIALS AND METHODS: procedures included closure of an atrial septal defect (23), atrial septectomy (2) and total cavopulmonary connection (4). Antegrade blood cardioplegia was delivered continuously for an average of 27 +/- 21 minutes at an average flow of 130 +/- 60 cc/min to maintain the aortic root pressure between 60 and 80 mmHg (mean 74 +/- 5 mmHg). Perfusion with regular blood commenced in the last 2 to 8 minutes and complete de-airing procedure was performed on the beating heart before removal of the aortic cross-clamp. RESULTS: all patients resumed sinus rhythm and all but one had normal cardiac output postoperatively. In one patient after cavopulmonary connection the inferior vena-cava to pulmonary-artery connection was taken down because of increased pulmonary vascular resistance resulting in low output state. All patients made an uneventful recovery without neurological complications. CONCLUSIONS: this initial experience suggests that normothermic aerobic arrest can be used safely in the repair of congenital defects and may provide superior myocardial protection for complex procedures such as the Fontan procedure.

Value of dobutamine/nitrate radionuclide angiography in predicting revascularization effects on ventricular function.

OBJECTIVE: Dobutamine and Nitrate Radionuclide Angiography (RNA) may help to distinguish viable from nonviable myocardium and to predict revascularization effects on LV function. SETTING: Ambulatory. EXPERIMENTAL DESIGN: Prospective. PATIENTS AND METHODS: We studied 12 patients (11 male, 1 female; mean age 56 +/- 10 years) with three-vessel disease, severe LV dysfunction, and prior MI for a mean follow-up time of 10 +/- 3.4 months. Thallium-201 scintigraphy favored potential viability in all patients: inducible ischemia with satisfactory perfusion in more than one coronary arterial territory. Global and regional LVEF's were calculated from preoperative RNA (baseline rest study and with continuous dobutamine infusion with gradual rate increase plus oral nitrates) and postoperative RNA at 1 and 6 months. RESULTS: There was no operative mortality, but two late deaths occurred. Symptomatically, most patients showed improvement. Global LVEF increased during dobutamine and nitrates preoperatively (p < 0.01), but not at 1 and 6 months postoperatively (without pharmacological intervention). Mean LVED volume was not significantly changed postoperatively. Regional EF improvement was found in 4 out of 9 LV wall segments under dobutamine and nitrates, and this increase persisted postoperatively at 1 and 6 months. CONCLUSIONS: Mild but significant increase in global LVEF during dobutamine and nitrates administration is not predictive of postoperative LVEF improvement. However, regional EF improvement appears to be predictive of post-revascularization LV functional improvement.

Open heart operation after pneumonectomy.

A coronary artery bypass operation was performed successfully on a 70-year-old patient who had undergone left pneumonectomy 40 years earlier. This case, together with a search of the literature and a mail survey among 118 cardiothoracic surgeons worldwide, yielded data on 27 such patients for review. Two patients died perioperatively. Three patients had pneumothorax, and 1 patient had recurrent pleural effusion. Difficulty in exposing the circumflex marginal branches was reported in 2 patients after left pneumonectomy. We conclude that with attention to the specific features of the preoperative, intraoperative, and postoperative management, open heart procedures can be performed on patients after pneumonectomy with acceptable operative mortality and morbidity.