Surgical treatment for chronic pulmonary thromboembolism in a patient with protein C deficiency

Medical therapy for chronic pulmonary thromboembolism is limited, and surgical treatment has become more frequent recently. We have performed pulmonary thromboendarterectomy on a patient with chronic pulmonary thromboembolism accompanied by protein C deficiency. The patient was a woman aged 68 years who had protein C deficiency. The preoperative condition was New York Heart Association functional class IV. Hypoxemia, marked pulmonary hypertension, and low cardiac output were observed. After a median sternotomy, moderate hypothermia was induced using a cardiopulmonary bypass, and thromboendarterectomy in the pulmonary artery was performed. The arterial blood oxygen concentration improved, and the mean pulmonary pressure decreased. The cardiac output also increased, and New York Heart Association functional class improved to I. Pulmonary thromboendarterectomy under cardiopulmonary bypass was effective for chronic pulmonary thromboembolism accompanied by protein C deficiency.     

Radical resection of a pulmonary blastoma involving the pulmonary artery.

Pulmonary blastoma is a rare malignant lesion with a poor prognosis. We described a case of a 47-year-old woman with a large biphasic pulmonary blastoma, involving the left pulmonary artery. Under cardiopulmonary bypass, it was treated with radical left intrapericardial pneumonectomy and pulmonary thromboendarterectomy. Subsequent chemotherapy and radiotherapy was used. Three years postoperatively, the patient was clinically and radiologically free of tumor.     

Pulmonary thromboendarterectomy combined with other cardiac operations: indications, surgical approach, and outcome

BACKGROUND: Patients with pulmonary hypertension due to chronic thromboembolic disease benefit from pulmonary thromboendarterectomy. A subset of these patients present with concomitant coronary or valvular disease. METHODS: From July 1990 to July 2000, 90 patients (68 males, 22 females, mean age 68 years) with pulmonary vascular resistance (PVR) ranging from 297 to 2261 dynes x sec x cm(-5) underwent pulmonary thromboendarterectomy in conjunction with coronary bypass grafting (59 patients), coronary artery bypass grafting/foramen ovale closure (24 patients), tricuspid annuloplasty (3 patients), mitral valve repair (2 patients), and aortic valve replacement (2 patients). The perioperative and hemodynamic outcomes of these patients were compared with the cohort of 1,100 isolated pulmonary thromboendarterectomies performed at our institution during this time. RESULTS: Overall perioperative survival (93.3%; 84 of 90 patients) and mean diminution in PVR (521 dynes x sec x cm(-5)) for patients undergoing combined operations were similar to those undergoing pulmonary thromboendarterectomy alone (94.2% survival; 1034 of 1100 patients; 547 dynes x sec x cm(-5) mean PVR reduction). Although patients undergoing combined operations were older (mean age 68 vs 50 years, p < 0.0001), had longer hospital stays (median 14 vs 9 days), and had worse left ventricular function (mean preoperative cardiac output 3.1 vs 4.4, p < 0.0001), there was no difference in cross-clamp time, resolution of tricuspid regurgitation, or postoperative systolic function between these two groups. CONCLUSIONS: Pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension may be performed safely in conjunction with other cardiac operations. Older patients evaluated for pulmonary thromboendarterectomy should be screened for concomitant coronary and valvular disease.     

Risk factors for pulmonary thromboendarterectomy

Pulmonary thromboendarterectomy is being performed with increasing frequency for incapacitating pulmonary hypertension caused by chronic large-vessel pulmonary embolism. However, patient-related risk factors and procedural complications associated with morbidity and mortality have not been fully defined. From Oct. 1, 1984, to April 10, 1989, we performed pulmonary thromboendarterectomy using deep hypothermia and circulatory arrest in 127 consecutive patients (62.2% male, mean age 50 +/- 16 [standard deviation], range 20 to 82 years) in whom the exposure and dissection of the pulmonary arteries and methods for myocardial protection have been standardized. End points for univariate and multivariate analyses of risk factors were reperfusion pulmonary edema leading to respiratory insufficiency as defined by ventilator dependency (greater than or equal to 5 days) (31.5%, 39/124) and hospital mortality (12.6%, 16/127). Multivariate analyses showed that ascites and need for 4 units of blood or more predicted ventilator dependency (p less than 0.03). Increased cardiopulmonary bypass times predicted both end points (p less than 0.03 to less than 0.0001), and failure to achieve at least a 50% reduction in pulmonary vascular resistance strongly predicted hospital death (p less than 0.0001). However, other factors that exhibited trends for association with one of the end points may prove important with a larger sample size. A hospital mortality rate of 12.6% for pulmonary thromboendarterectomy is acceptable when compared with approximately 25% for heart-lung transplantation, which is the only therapeutic alternative. Increased ventilator dependency and hospital mortality can be anticipated with longer cardiopulmonary bypass times and inadequate reduction of pulmonary vascular resistance.     

Chronic pulmonary thromboendarterectomy complicated by antithrombin III deficiency and antiphospholipid syndrome

Pulmonary thromboendarterectomy was performed on two patients with chronic pulmonary thromboembolism showing thrombotic tendency. Patient 1 was a 25-year-old male with the disease complicated by congenital antithrombin III deficiency. Patient 2 was a 21-year-old male with the disease complicated by antiphospholipid syndrome. Both patients were admitted to the center upon showing dyspnea. Lung perfusion scintigraphy revealed multiple defects in the right and left lungs. Pulmonary arteriography showed occlusion and stenosis from lobar to segmental arteries. Cardiac catheterization showed marked pulmonary hypertension. Pulmonary angioscopy confirmed the presence of organized thrombi while an intravascular ultrasound revealed a thinkening of the pulmonary arterial walls in both lungs. After the insertion of an inferior vena cava filter in each patient, surgery was performed. Following a median sternotomy, a cardiopulmonary bypass was utilized to induce deep hypothermia at a pharyngeal temperature of 16 °C, after which a thromboendarterectomy of the bilateral pulmonary arteries was performed under intermittent circulatory arrest. A large amount of organized thrombi was extracted from these arteries. After surgery, both patients showed good postoperative outcome with improved blood flow in both lungs, reduced pulmonary arterial pressure and increased cardiac output.     

Operation for chronic pulmonary thromboembolism accompanied by thrombophilia in 8 patients

Background. Medical therapy for chronic pulmonary thromboembolism is limited, and surgical treatment has become more frequent recently. We have performed pulmonary thromboendarterectomy on 8 patients with chronic pulmonary thromboembolism accompanied by thrombophilia.

Methods. The patients were 6 men and 2 women aged 21 to 56 years (mean, 35 years). Five patients had antiphospholipid syndrome, 2 had protein C deficiency, and 1 had congenital antithrombin III deficiency. The preoperative condition was New York Heart Association functional class III in 5 and class IV in 3. Hypoxemia, marked pulmonary hypertension (mean pulmonary artery pressure, 47 ± 6.7 mm Hg), and low cardiac output were observed in all patients. After a median sternotomy, deep hypothermia was induced using a cardiopulmonary bypass, and pulmonary thromboendarterectomy in the bilateral pulmonary arteries was performed under intermittent circulatory arrest.

Results. There were no operative deaths. Long-term respiratory management was needed postoperatively by 3 patients. In the remaining 5 patients, no reperfusion injury was observed. The arterial blood oxygen concentration improved, and the mean pulmonary pressure decreased to 16 ± 5.5 mm Hg. The cardiac output also increased, and New York Heart Association functional class improved to I in 4 and II in 4 patients.

Conclusions. Pulmonary thromboendarterectomy under deep hypothermic intermittent circulatory arrest was effective for chronic pulmonary thromboembolism accompanied by thrombophilia for which medical treatment is of limited value.     

Pulmonary artery perfusion with protective solution reduces lung injury after cardiopulmonary bypass

BACKGROUND: The inflammatory response and higher temperature of lung tissue during cardiopulmonary bypass can result in lung injury. This study was to evaluate the protective effect of pulmonary perfusion with hypothermic antiinflammatory solution on lung function after cardiopulmonary bypass. METHODS: Twelve adult mongrel dogs were randomly divided into two groups. The procedure was carried out through a midline sternotomy, cardiopulmonary bypass was established using cannulas placed in the ascending aorta, superior vena cava, and right atrium near the entrance of the inferior vena cava. After the ascending aorta was clamped and cardioplegic solution infused, the right lung was perfused through a cannula placed in the right pulmonary artery with 4 degrees C lactated Ringer's solution in the control group (n = 6) and with 4 degrees C protective solution in the antiinflammation group (n = 6). Antiinflammatory solution consisted of anisodamine, L-arginine, aprotinin, glucose-insulin-potassium, and phosphate buffer. Plasma malondialdehyde, white blood cell counts, and lung function were measured at different time point before and after cardiopulmonary bypass; lung biopsies were also taken. RESULTS: Peak airway pressure increased dramatically in the control group after cardiopulmonary bypass when compared with the antiinflammation group at four different time points (24 +/- 1, 25 +/- 2, 26 +/- 2, 27 +/- 2 cm H2O versus 17 +/- 2, 18 +/- 1, 17 +/- 1, 18 +/- 1 cm H2O; all p < 0.01). Pulmonary vascular resistance increased significantly in the control group than in the antiinflammation group at 5 and 60 minutes after cardiopulmonary bypass (1,282 +/- 62 dynes x s x cm(-5) versus 845 +/- 86 dynes x s x cm(-5) and 1,269 +/- 124 dynes x s x cm(-5) versus 852 +/- 149 dynes x s x cm(-5), p < 0.05). Right pulmonary venous oxygen tension (PvO2) in the antiinflammation group was higher than in the control group at 60 minutes after cardiopulmonary bypass (628 +/- 33.3 mm Hg versus 393 +/- 85.9 mm Hg, p < 0.05). The ratio of white blood cells in the right atrial and the right pulmonary venous blood was lower in the antiinflammation group than in the control group at 5 minutes after the clamp was removed (p < 0.05). Malondialdehyde were lower in the antiinflammation group at 5 and 90 minutes after the clamp was removed (p < 0.01 and p < 0.05, respectively). Histologic examination revealed that the left lung from both groups had marked intraalveolar edema and abundant intraalveolar neutrophils, whereas the right lung in the control group showed moderate injury and the antiinflammation group had normal pulmonary parenchyma. CONCLUSIONS: Pulmonary artery perfusion using hypothermic protective solution can reduce lung injury after cardiopulmonary bypass.     

The evolution and the current state of the art of pulmonary thromboendarterectomy.

Optimal reduction in pulmonary vascular resistance caused by chronic pulmonary embolism is obtained by bilateral pulmonary thromboendarterectomy with removal of occlusive material in all bronchopulmonary segmental arteries that are partially or completely obstructed. The most effective way to obtain this goal is the use of median sternotomy with cardiopulmonary bypass, deep hypothermia, and intermittent periods of circulatory arrest. During circulatory arrest, thromboendarterectomy is performed by specially designed dissectors that allow simultaneous dissection and removal of blood from the surgical field. The operative mortality rate for pulmonary thromboendarterectomy at the University of California, San Diego, between 1990 and 1998 was 9.2% in 1,049 patients.     

Surgical treatment for pulmonary arterial injury caused by sewing needles]

A 41-year-old woman was found lying in her home, which was on fire, and was brought to our hospital by ambulance. Her complaint was severe dyspnea, and a respirator was needed. Contusion and abrasion were present on her anterior chest. A roentgenogram of her chest disclosed cardiac enlargement and two linear metallic shadows. A computed tomographic scan of the chest showed cardiac tamponade and a needle from the chest wall to the main pulmonary artery. Through a median sternotomy approach, the pericardium was opened. About 200 ml of blood was pooled in the pericardium cavity, and a needle was found in the main pulmonary artery. The needle was removed and the bleeding point was closed using suturing with 5-0 prolene without cardiopulmonary bypass.     

Thromboembolic obstruction of the pulmonary artery treated by endarterectomy

Endarterectomy of a totally occluded right pulmonary artery by median sternotomy with cardiopulmonary bypass and intermittent circulatory arrest is described. The nature of the thrombus encountered and brisk backbleeding from the endarterectomized vessels predicted the functional improvement seen in the patient postoperatively. Reperfusion edema, which often complicates pulmonary artery thromboendarterectomy, was not observed. Preoperative assessment, postoperative management, and technical aspects of the operative procedure used in treating patients with thromboembolic obstruction of the pulmonary arteries are discussed.     

Surgical treatment for chronic thromboembolic pulmonary hypertension under profound hypothermia and circulatory arrest in 24 patients

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is a serious disease that induces hypoxemia and pulmonary hypertension, eventually leading to respiratory failure and right heart failure. We evaluated the results of surgical treatment in patients undergoing circulatory arrest under profound hypothermia. METHODS: Between February 1995 and June 1999, 24 cases of CTEPH were surgically treated. The age of patients (11 males and 13 females) ranged from 21 to 71 years (mean 49+/-15 years). Because of hypoxemia, severe pulmonary hypertension (mean pulmonary artery pressure 45+/-7 mmHg ), and low cardiac output, the functional class of these patients was New York Heart Association (NYHA) III or IV. Following a median sternotomy, profound hypothermia was induced using cardiopulmonary bypass, and pulmonary thromboendarterectomy in the bilateral pulmonary arteries was performed under intermittent circulatory arrest. Surgery was performed emergently in four patients. RESULTS: Of these 24 patients, 2 of 20 patients who underwent elective surgery and 3 of 4 patients who underwent emergent surgery died in the hospital. Symptoms of CTEPH markedly improved in 18 patients who survived the surgery. Pulmonary arterial pressure was decreased to 16+/-6 mmHg, and cardiac output was increased. CONCLUSIONS: When CTEPH is resistant to medical treatment, surgical treatment is useful. When surgical indications are carefully selected, pulmonary thromboendarterectomy using intermittent circulatory arrest under profound hypothermia is quite effective for treating CTEPH.     

Resection of central primary pulmonary artery sarcoma.

Primary sarcomas of the pulmonary arteries are rare, and the diagnosis is in the majority of the reported cases established postmortem. Surgical resection of these centrally located tumors has been performed either by pneumonectomy and/or local tumor resection. We report on two patients with sarcomas of the central pulmonary arteries who underwent successful resection of the tumor and prosthetic replacement of the arteries under cardiopulmonary bypass. One patient required additional thromboendarterectomy of the right pulmonary artery branches because of secondary thrombus formation. As primary pulmonary artery sarcomas are refractory to both chemotherapy and radiation, surgical resection remains the only means of treatment. The prognosis depends entirely upon resectability, which, if necessary, should be performed with the aid of cardiopulmonary bypass. In this way, lung resection may be avoided.     

Peripheral pulmonary artery aneurysm in a patient with limited respiratory reserve: controlled resection using cardiopulmonary bypass

Pulmonary artery aneurysms are rare lesions for which operative management is not frequently undertaken. When operation is indicated, central lesions involving the pulmonary trunk, right main pulmonary artery, or left main pulmonary artery are repaired using cardiopulmonary bypass. Peripheral aneurysms in segmental intrapulmonary arteries have been managed most frequently by lobectomy, but occasionally by aneurysmectomy and pulmonary arterial repair. We used cardiopulmonary bypass for peripheral pulmonary aneurysmectomy in a patient with limited respiratory reserve because he had undergone prior contralateral bilobectomy; this allowed controlled resection while preserving a maximal amount of pulmonary parenchyma.     

Protective effect of antioxidants on pulmonary endothelial function after cardiopulmonary bypass

OBJECTIVES: Pulmonary endothelium-dependent vasodilation is impaired after cardiopulmonary bypass. One explanation might be the generation of reactive oxygen species during the period without flow in the pulmonary artery. The aim of the current study was to investigate if treatment with antioxidants could improve pulmonary endothelial function after cardiopulmonary bypass and influence the blood oxidative status. DESIGN: A prospective, randomized, double-blind study. SETTING: The operating room, intensive care unit, and the biochemistry laboratory in University Hospitals. PARTICIPANTS: Patients scheduled for cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: Treatment with vitamin E, vitamin C, allopurinol, and acetylcysteine (n = 12) or placebo (n = 10). MEASUREMENTS AND MAIN RESULTS: The pulmonary reactivity to an infusion of acetylcholine and markers of oxidative stress in blood were measured before and after cardiopulmonary bypass. Sixteen control patients received saline instead of acetylcholine. Before surgery the pulmonary vascular resistance index decreased during infusion of acetylcholine by 24% and 21% in the treatment and placebo groups. After surgery the decrease was 20% and 8%, respectively, (p = 0.422 and p = 0.026) compared with preoperative response. Pulmonary vasodilation induced by acetylcholine was better maintained in the group treated with antioxidants (p = 0.048). In the treatment group, the blood concentrations of early intermediates of lipid peroxidation were higher, but not that of the end products. Glutathione and oxidized glutathione increased after cardiopulmonary bypass in the treatment group. CONCLUSION: The better maintained endothelium-dependent vasodilation after cardiopulmonary bypass in the treatment group indicated that antioxidant therapy reduced endothelial dysfunction.     

Pulmonary embolectomy for a patient of chronic pulmonary embolism

Chronic pulmonary embolism is resistant to medicinal treatment. This is a report of the successful operation for chronic pulmonary embolism. A 29-year-old man suffered from dyspnea attack twice half a year in spite of intensive anticoagulant therapy. Cardiac catheterization showed pulmonary hypertension of 72/25 mmHg, mean 42 mmHg. Pulmonary angiogram demonstrated emboli in the right pulmonary artery and pulmonary perfusion scintigram revealed large perfusion defect in the right lung. The patient underwent pulmonary embolectomy after the total cardiopulmonary bypass. After surgery, blood gas showed an increased PaO2 from 65 to 77 mmHg. Pulmonary artery pressure decreased to 39/12 mmHg, mean 23 mmHg. Pulmonary arteriogram showed increased pulmonary vascular beds and pulmonary scintigram showed an increased perfusion in the right lung. The patient has been free from symptom and a half year after surgery.     

慢性肺动脉血栓栓塞的外科治疗

目的 探讨肺动脉切开取栓和肺动脉内膜剥脱术治疗慢性肺动脉栓塞的方法、围手术期处理及外科治疗的安全性。方法 回顾性总结1999年3月至2004年3月间12例慢性肺动脉血栓栓塞症患者的诊治过程和临床经验。均在深低温低流量停循环下行肺动脉切开取栓及内膜剥脱术,术中泵入前列腺素E1或吸入一氧化氮。结果 术后即刻6例患者肺动脉压下降20—40mmHg(1mmHg=0．133kPa);术后12例患者均有肺水肿表现,其中8例较重,采用呼吸机辅助呼吸治愈,1例术后19d死于严重的肺部感染和再次肺动脉栓塞,其余11例术后随访2个月-5年,平均43．5个月,临床症状均有减轻、活动能力均有明显提高。结论 肺动脉内膜剥脱是治疗慢性肺动脉栓塞的有效方法;围手术期应注意处理好肺再灌注损伤、肺水肿等并发症,术前正确的评估和适应证的选择是提高慢性肺动脉栓塞外科治疗安全性的关键。     

Pulmonary artery balloon counterpulsation for treatment of intraoperative right ventricular failure

Pulmonary artery balloon counterpulsation was used in 3 patients who underwent open-heart operation for the treatment of acquired cardiac lesions. This form of support was initiated because the patients could not be weaned from cardiopulmonary bypass even with intraaortic balloon counterpulsation and maximal pharmacological support. After pulmonary artery balloon pumping was instituted, cardiopulmonary bypass was successfully terminated in all 3 patients. One of them is alive and well one year after operation.     

Pulmonary artery sling with tracheal stenosis: primary one-stage repair in infancy.

Pulmonary artery sling is often associated with tracheal stenosis. In many cases repair of the vascular anomaly alone does not relieve dyspnea. Primary one-stage repair with long segment tracheal resection (2.4 cm) and relocation of the left pulmonary artery using cardiopulmonary bypass and deep hypothermic circulatory arrest is described in a 6.5-month-old girl weighing 6.5 kg. This technique resulted in normal ventilation and pulmonary flow distribution.     

OPCAB surgery after right pneumonectomy

Coronary artery bypass grafting was performed in a 58-year-old patient 3 years after right pneumonectomy for nonsmall cell lung cancer stage IIIa. The CT scan demonstrated a marked shift of the mediastinum into the right chest, but revealed a feasible access to the left coronary artery by median sternotomy. Pulmonary function was impaired. Off-pump coronary artery bypass grafting was performed to avoid cannulation under more difficult conditions and to prevent negative side effects of cardiopulmonary bypass to the pulmonary function. The postoperative recovery was uneventful. We discuss issues related to this special subgroup of patients.     

Regression of postobstructive vasculopathy after revascularization of chronically obstructed pulmonary artery

OBJECTIVES: Pulmonary vascular resistance decreases dramatically after pulmonary thromboendarterectomy and further improves in time. This may reflect the slow regression of postobstructive pulmonary vasculopathy. We hypothesized that postobstructive pulmonary vasculopathy may regress after reperfusion in a piglet model of chronic (5 weeks) left pulmonary artery obstruction. METHODS: The ligated left pulmonary artery was reimplanted into the pulmonary arterial trunk. Pulmonary artery blood flow and pressure were measured 2 days and 5 weeks after reperfusion. Pulmonary artery smooth muscle thickness, endothelium-dependent relaxation, and left lung endothelial nitric oxide synthase activity and expression were assessed 5 weeks after ligation (n = 10) and 5 weeks after reperfusion (n = 10), and compared with a sham group (n = 10). Patency of the anastomoses and systemic blood supply to the lung were assessed by pulmonary angiography and nonselective thoracic aortography, respectively. RESULTS: Angiography showed that pulmonary artery anastomoses were patent in all animals. Five weeks after reperfusion, left pulmonary blood flows were similar to those in the sham animals, and systemic blood supply to the left lung decreased. Left pulmonary vascular resistance decreased by 50% at 5 weeks after reperfusion compared with 2 days after reperfusion (P =.0009). Medial muscle thickness of the left pulmonary artery greater than 600 microm increased 5 weeks after ligation and regressed to sham values 5 weeks after reperfusion (P =.001). Endothelium-dependent relaxation was only partially restored 5 weeks after reperfusion, whereas left lung endothelial nitric oxide synthase expressions and activities returned to sham values. CONCLUSIONS: This study shows that postobstructive pulmonary vasculopathy induced by ligation of the pulmonary artery for 5 weeks regresses after reperfusion, accounting for the progressive improvement in hemodynamics after thromboendarterectomy.