The St Jude Medical symmetry aortic connector system for proximal vein graft anastomoses in coronary artery bypass grafting

OBJECTIVES

A new device designed to create proximal vein graft anastomoses to the aorta in coronary artery bypass grafting was recently developed by the St Jude Medical Anastomotic Technology Group (Minneapolis, Minn). This new anastomosis system consists of a nickel-titanium (nitinol) connector, an aortic cutter, and a delivery device.

METHODS

The loading of the vein on the aortic connector and its delivery to the aorta are described. In 43 consecutive patients (mean age 68 +/- 10 years, age range 33-91 years), 65 proximal vein graft anastomoses were performed with the new system. Intraoperative flow rates were assessed for all grafts according to the transit time principle.

RESULTS

All connector anastomoses were performed without the use of any aortic clamp. Times to complete these mechanical anastomoses were less than 10 seconds in all cases. Hemostasis was instantaneous in all cases, with only 3 system failures. These connectors were easily removed so that the anastomoses could be performed with standard suturing technique through the same aortotomy without complications. All vein grafts were patent at the end of the procedure, and there were no intraoperative or postoperative complications related to the device.

CONCLUSIONS

The aortic connector system was easy to handle and allowed quick creation of reliable, reproducible, and uniform anastomoses. In addition, anastomoses could be done without any clamping of the aorta, which is especially attractive for off-pump procedures, because aortic manipulation and therefore the risks of embolism and aortic dissection would be further minimized. In on-pump cases this technique would facilitate the single-clamp technique, again minimizing aortic manipulation.

Paravalvular leak and other events in silzone-coated mechanical heart valves: a report from AVERT

BACKGROUND

The Artificial Valve Endocarditis Reduction Trial (AVERT) was designed to compare endocarditis rates in Silzone versus conventional valves. Recruitment ended January 21, 2000, because of higher rates of paravalvular leakage in patients receiving the Silzone prosthesis. The present analysis determined late event rates that might be used in the management of approximately 36,000 patients who have received the Silzone prosthesis.

METHODS

A total of 807 patients in 19 centers in North America and Europe were randomized. Mean age was 61+/-11 years; 41% were women. Operations included aortic valve replacement in 59%, mitral valve replacement in 32%, and aortic and mitral valve replacements in 9%; 41% had concomitant operations (26% coronary artery bypass grafting).

RESULTS

Major paravalvular leakage (followed by repair, explant, or mortality) occurred in 18 of 403 patients receiving Silzone valves and 4 of 404 patients without Silzone valves (2-year event-free rates: 91.1% versus 98.9% conventional, p < 0.003). Similarly, 2-year freedom from any explant was lower in the Silzone arm (19 versus 2 events; 90.1% versus 99.4%, p = 0.0002). Rates of mortality and stroke were similar during follow-up.

CONCLUSIONS

Continued follow-up of AVERT supports the conclusion that the Silzone prosthesis has increased risk of paravalvular leakage requiring reoperation. Overall survival is similar in the two groups.

Quality of life after interventions on the thoracic aorta with deep hypothermic circulatory arrest

OBJECTIVE

Assessment of quality of life (QL) in patients undergoing major surgical procedures is of increasing interest. We focused on surgery of the thoracic aorta requiring deep hypothermic circulatory arrest (DHCA). Aim of this study was to assess QL after thoracic aortic surgery with DHCA, using the Short Form 36 Health Survey (SF-36) questionnaire.

METHODS

Between 01/94 and 12/99 212 (59.1%) out of a total of 359 interventions on the thoracic aorta were performed under DHCA, with an early mortality of 13.7% (28 patients). During an average follow-up of 3.2+/-1.3 years, 27 patients died (15.2%) and five patients (2.8%) were lost. A total of 145 patients (81.9%) had a complete follow-up.

RESULTS

125 of the 145 SF-36 questionnaire handed out were answered correctly (86.2%). In relation to a standard population (z=0), the most important deficits were found in physical function (z=-0.53) and role limitations because of physical health (z=-0.42). Good results were found regarding the aspect of pain (z=0.28), social functioning (z=0.02) and vitality (z=-0.02). Overall QL in patients having been operated for aortic aneurysm was better than for patients with acute type A-dissection.

CONCLUSION

Despite restrictions in physical functioning and role limitation because of physical health, QL in patients after interventions on the thoracic aorta with DHCA is fairly good and, for patients being operated for aortic aneurysm, comparable to an age-matched standard population. Patients having being operated electively for aortic aneurysm enjoyed a better QL than patients having been operated emergently for acute type A dissection.

Intracardiac resection of a metastatic choriocarcinoma

BACKGROUND

Postpartal choriocarcinoma is a rare complication of pregnancy, which usually responds well to chemotherapy, even in advanced stages. Metastatic heart involvement typically characterizes a widely advanced disease, requiring palliative treatment.

CASE

A 41-year-old woman with disseminated choriocarcinoma following a full-term pregnancy presented with clinical signs of severe dyspnea. Pulmonary hypertension and a floating left atrial tumor were diagnosed upon echocardiography. Tumor resection was performed by intracardiac surgery. Histological examination revealed a metastatic thrombus of a choriocarcinoma that had obstructed the right inferior pulmonary vein at the entrance to the left atrium. The patient was treated with high-dose chemotherapy. After a 1-year follow-up the patient continues to be in full remission.

CONCLUSION

Tumor reductive surgery followed by high-dose chemotherapy might be a useful approach in patients with metastatic choriocarcinoma even in cases of rare tumor sites.

Minimizing aortic manipulation during OPCAB using the symmetry aortic connector system for proximal vein graft anastomoses

BACKGROUND

Since minimal invasive techniques have become increasingly common in coronary artery bypass grafting (CABG), there has been renewed interest in facilitated mechanical anastomoses devices that might have the potential of replacing the standard suturing techniques in vascular anastomoses. We report our initial experience with the successful creation of mechanical proximal vein graft anastomoses in off-pump coronary artery bypass operations.

METHODS

From August to December 2000, we investigated the first 20 consecutive patients who underwent CABG on the beating heart without extracorporeal circulation and who received at least one mechanical proximal vein graft anastomosis with the St. Jude Medical Symmetry aortic connector system without side-clamping of the aorta. We evaluated the different components of the system, the feasibility of such anastomoses, and the intraoperative flow measurements of the grafts using transit time methods.

RESULTS

A total of 32 proximal vein graft anastomoses were performed with the aortic connector system. Hemostasis was instantaneous in all cases except one, in which the connector was removed and the anastomosis was hand-sewn without complications. All other vein grafts were patent at the end of the procedure; intraoperative flow measurements were 39 +/- 25 mL/min for single vein grafts (n = 20) and 69 +/- 25 mL/min for sequential grafts (n = 11).

CONCLUSIONS

The St. Jude Medical Symmetry aortic connector system is a user-friendly, effective, quick, and reliable device for sutureless proximal vein graft anastomosis in CABG. This system allows the construction of uniform and geometrically perfect anastomoses and does not require aortic side-biting. This technology is attractive for all CABG procedures because aortic manipulation is reduced. In off-pump surgical procedures the connector system allows aortic manipulation to be minimized, potentially reducing embolization from aortic wall debris.

Pneumonia after cardiac surgery is predictable by tracheal aspirates but cannot be prevented by prolonged antibiotic prophylaxis

BACKGROUND

The purpose of this study was to assess the value of tracheal aspirate as a predictor of pneumonia after coronary artery bypass grafting and to evaluate the efficacy of prolonged perioperative antibiotic prophylaxis.

METHODS

Tracheal aspirates of 500 patients undergoing coronary artery bypass grafting were taken immediately after intubation and analyzed for microorganisms by Gram stain and semiquantitative microbiologic cultures. All patients received 2 g ceftriaxone as a single-dose perioperative antibiotic prophylaxis before operation. Results of Gram stains were available before the patients were transferred to the intensive care unit. After the results were known, both groups of patients (positive Gram stain, group 1; negative Gram stain, group 2) were randomly assigned to either conventional antibiotic prophylaxis (A), consisting of ceftriaxone 2 g on postoperative day 1, or prolonged antibiotic prophylaxis (B), with ticarcillin + clavulanic acid 3 x 5.2 g during 72 hours.

RESULTS

From 500 patients, 91 had a positive Gram stain whereas 409 had a negative one. The incidence of pneumonia was significantly higher in patients with preoperative positive tracheal aspirates (15.3%) than in patients with a negative one (3.6%; p < 0.01). However, prolonged prophylaxis did not reduce the rate of postoperative pneumonia, which was as high as 13% in untreated positive patients versus 17% in treated positive patients, and 2% in untreated negative patients versus 4% in treated patients. In patients who had pneumonia, there was a high correlation between the microorganisms found in preoperative aspirates and those observed when aspirates were repeated (100% correlation in patients with conventional antibiotic prophylaxis and 87% in those with prolonged prophylaxis).

CONCLUSIONS

Early postoperative pneumonia (<7 days) is most likely caused by microorganisms that colonize the respiratory tract before operation. The risk of pulmonary infection after coronary artery bypass grafting can be predicted from the preoperative tracheal aspirates. Prolonged perioperative antibiotic prophylaxis has no efficacy in reducing the incidence of pulmonary infections.

Constrictive tuberculous pericarditis in a HIV-positive patient

Constrictive pericarditis is a relatively rare clinical manifestation nowadays. We present the case of an HIV-positive patient with constrictive calcified pericarditis due to an infection with Mycobacterium tuberculosis. Pericardectomy was performed. The therapeutical approach is discussed and the literature is reviewed.

Sutureless mechanical anastomosis of a saphenous vein graft to a coronary artery with a new connector device

Construction of vascular anastomoses by manual suturing is a highly skilled and time-consuming procedure. The St Jude Medical Anastomotic Technology Group has developed a sutureless mechanical anastomosis device, which, when tested in animals, produced anastomoses in less than 3 min and with little training. Here we present the results of the first clinical saphenous-vein to coronary-artery anastomosis by means of this device.

Acute and chronic effects of transmyocardial laser revascularization in the nonischemic pig myocardium by using three laser systems

BACKGROUND AND OBJECTIVE

Transmyocardial laser revascularization (TMLR) improves symptoms in patients with coronary heart disease. It is based on the hypothesis of direct perfusion of ischemic myocardium by means of laser-created channels. Three different lasers were used to study alternative effects on myocardium.

STUDY DESIGN/MATERIALS AND METHODS

The present study was conducted to evaluate comprehensively and compare the short and long-term tissue effects and the basic interaction mechanisms of CO2, Ho:YAG, and Er:YAG laser radiation with myocardium. The dynamics of laser-induced impacts in gel used as tissue phantom was visualized by time-resolved flash photography. Pressure measurements performed during perforation of myocardium in vitro revealed the explosive character of the ablation process. Channels made into the left ventricle of normal pig hearts were examined immediately and 6 weeks after creation.

RESULTS

Regardless of laser source, all channels became occluded within 6 weeks by scar. Minimal acute thermal damage by Er:YAG laser corresponded to smaller scars. Pulsed Ho:YAG caused stronger tissue tearing than continuous wave CO2 irradiation. An increased volume density of intramyocardial vessels was found about the scars 6 weeks after treatment with all lasers.

CONCLUSION

The laser sources permitted to study outcome of pressure effects and thermal damage in vivo. There were only minor differences between the three laser systems used. Rapid channel occlusion suggests that rather than revascularization, subsidiary physiologic tissue effects elicited by the thermal, oxidative, or mechanical action of the laser impact may contribute to the beneficial clinical effects of TMLR.

Modified repair of mixed total anomalous pulmonary venous connection

Mixed total anomalous pulmonary venous connection (TAPVC) is a rare condition, accounting for only 5% of diagnosed TAPVC. It is associated with a poor prognosis unless surgically corrected by connecting the pulmonary venous sinus to the left atrium and optionally dividing the abnormal connection to the systemic venous system. We report a modified technique of complete intracardiac repair of mixed supracardiac and cardiac TAPVC in a 3-year-old child without pulmonary venous sinus-to-left atrium anastomosis.

Thoracoabdominal aortic repair in a 190-kg patient: optimized perfusion with two oxygenators

A 190-kg patient was referred because of an acute type B aortic dissection. Conservative management was initially performed but the 34-year-old patient was shown to have an increasing aortic diameter 2 months later and was scheduled for elective repair of the thoracoabdominal aorta. To anticipate potential difficulties with perfusion and oxygenation the cardiopulmonary bypass circuit was constructed with two parallel oxygenators, which allowed an adequate oxygen supply through all phases of the intervention and accelerated the estimated rewarming time.

Atherosclerotic disruption of the aortic arch during coronary artery bypass operation

A 70-year-old-man presented with a symptomatic three vessel coronary artery disease and was scheduled for myocardial revascularization. During extracorporeal circulation an intrathoracal bleeding occurred and aortic rupture was suspected. An iatrogenic plaque rupture in the concavity of the aortic arch was found due to cannulation attempts. The aortic arch was grafted in the so-called elephant trunk technique. Thereafter bypass grafts were anastomosed to the stenosed coronary arteries. The patient was discharged from hospital after 2 weeks in good condition.

Outcome of thoracoabdominal aortic operations using deep hypothermia and distal exsanguination

BACKGROUND

Operation of the descending and thoracoabdominal aorta may be affected by a significant perioperative morbidity, mainly because of ischemic damage of the spinal cord and malperfusion of the abdominal organs.

METHODS

A comparative analysis was performed on two consecutive series of patients operated between 1982 and 1998. Group 1 consisted of 90 patients operated with moderate hypothermic left heart bypass. Group 2 included 38 patients operated using deep hypothermic cardiopulmonary bypass and a period of circulatory arrest while performing the proximal anastomosis and distal exsanguination during confection of the distal anastomosis.

RESULTS

Main demographic factors and causes of the aortic disease were similar in both groups. Early mortality was significantly higher in the group of patients with aortic cross-clamping (15 of 90, 16%) than in those operated with circulatory arrest (2 of 38, 5.2%), p < 0.001. Paraplegia occurred in 8 patients in the group operated with mild hypothermia (8.8%) but in only 1 patient (2.6%) when deep hypothermia had been used.

CONCLUSIONS

In our experience, deep hypothermia combined with distal exsanguination significantly improved the early postoperative outcome after operation of the descending and thoracoabdominal aorta. This technique allowed easy confection of proximal and distal anastomoses, and the duration of the operation was not prolonged significantly through this approach.

Age does not influence early and late tumor-related outcome for bronchogenic carcinoma

BACKGROUND

The influence of age on early and late outcome after surgical resection of bronchogenic carcinoma is unknown. In an attempt to clarify this issue, we reviewed the outcome of 212 consecutive patients with primary lung cancer who had surgical treatment for bronchogenic carcinoma.

METHODS

Ninety-two patients were younger than 50 years (group 1), and 120 patients were older than 70 years of age (group 2). Squamous cell carcinoma and adenocarcinoma were the most common histologic types in both groups. According to the new international staging classification, a similar proportion of stage I, II, and III were observed in both groups.

RESULTS

Only the rate of pneumonectomy was significantly higher in younger patients (41% versus 22%, p = 0.002). The overall operative mortality rate in group 1 was 2.2% and 2.6% after pneumonectomy. In group 2 the overall mortality rate was 2.5% and 3.8% after pneumonectomy. Advanced age did not affect operative mortality. The adjusted (tumor-related) survival rate at 5 years was 56% in group 1 and 53% in group 2 (p = 0.93). The adjusted survival rate for patients with stage I was 61% in group 1 and 65% in group 2 (p = 0.21), and for stage IIIa 39% in group 1 and 48% in group 2 (p = 0.43). The adjusted 5-year survival rate was 56% in group 1 and 59% in group 2 for squamous cell carcinoma (p = 0.53) and 49% in group 1 and 42% in group 2 for adenocarcinoma (p = 0.76).

CONCLUSIONS

Perioperative risk and midterm survival were similar in younger and older patients after surgical resection of bronchogenic carcinoma. We believe that this result is because surgical candidates constitute already a highly selected group of patients. From these data it is not possible to conclude that biologic behavior of lung cancer is more aggressive in younger patients.

Separate revascularization of the visceral arteries in thoracoabdominal aneurysm repair

We successfully repaired a ruptured aortic patch containing the visceral arteries after thoracoabdominal aneurysm repair in a young patient with Marfan syndrome. This unexpected and tricky situation was treated by separate revascularization of each visceral artery using small-caliber prosthetic grafts as interposition between the aortic prosthesis and the ostia of the visceral arteries.

Pediatric open heart operations without diagnostic cardiac catheterization

BACKGROUND

Echocardiography allows for an adequate noninvasive preoperative evaluation in an increasing proportion of pediatric patients before open heart operations. The present study assessed the diagnostic accuracy of both invasive and noninvasive preoperative evaluation in children with congenital heart disease.

METHODS

We prospectively evaluated the accuracy of preoperative noninvasive or invasive diagnostic methods. Preoperatively established diagnosis was compared with the intraoperative diagnosis made by surgical inspection and routine perioperative transesophageal echocardiography.

RESULTS

During the study period of 30 months (ending in December 1997) 209 open-heart procedures were performed. Eighty-one patients (39%) were in the first year of life at the time of surgery, and 43% of all patients had symptoms. Noninvasive preoperative diagnosis using echocardiography was done exclusively in 142 patients (68%). Of the 67 children who had preoperative catheterization, 4 (6%) showed an additional intraoperative finding that modified the surgical approach in 2 of them. In the 142 patients who had echocardiographic preoperative assessment, the surgeons were confronted with a previously undiagnosed finding in 12 patients (8.5%). The finding was considered significant (prolongation of cardiopulmonary bypass time) in 2 patients and might have affected the outcome in 1 of them, a neonate with transposition of the great arteries and a preoperatively undiagnosed intramural coronary artery, who died postoperatively despite a technically adequate repair.

CONCLUSIONS

In many infants and children, diagnostic work-up before open heart operations could be adequately based on an exclusively noninvasive basis by relying on echocardiography alone.

Perioperative bleeding and thromboembolic risk during non-cardiac surgery in patients with mechanical prosthetic heart valves: an institutional review

BACKGROUND AND AIMS OF THE STUDY

The study aim was to determine the risk of thromboembolic and bleeding complications in patients with mechanical heart valve prostheses who underwent non-cardiac surgery under different regimens of perioperative anticoagulation. Data were analyzed on the basis of surgery type and underlying disease.

METHODS

A series of 235 patients (mean age 63 +/- 4.5 years) with one or two mechanical heart valves underwent subsequent non-cardiac surgery comprising abdominal, vascular and thoracic, orthopedic, urologic, neurosurgery, ENT, plastic and reconstructive, and gynecologic operations. Mean interval between heart valve replacement and non-cardiac surgery was 3.9 +/- 3.3 years. Perioperative oral anticoagulation was managed by discontinuation of oral anticoagulation and intravenous heparin administration; or by discontinuation and early postoperative re-institution of oral anticoagulation without intravenous heparin; or by no withdrawal of oral anticoagulation. Patients with bioprostheses were excluded.

RESULTS

Overall hospital mortality during non-cardiac surgery was 2.9%. Thromboembolic events included cerebral embolism with transient deficit (n = 3), residual defect (n = 1) and irreversible defect (n = 1), as well as peripheral embolism (n = 11). Hemorrhagic complications included wound hematoma (n = 10) and increased postoperative bleeding (n = 8) with re-exploration in five patients. Thromboembolic complications occurred most often in patients with prosthetic mitral valve and atrial fibrillation; the lowest risk was in patients with sinus rhythm after aortic valve replacement. Most complications occurred after discharge and in patients with surgery for malignancy, within 10 days of instituting oral anticoagulation, and despite a therapeutic INR value.

CONCLUSIONS

Minor surgical procedures can be performed safely without discontinuing anticoagulation. When major non-cardiac surgery is planned, discontinuing oral anticoagulation and starting perioperative intravenous heparin minimizes bleeding and thromboembolic risks. Thromboembolic complications may occur within one month of surgery, despite adequate oral anticoagulation, though permanent morbidity is low.

Evaluation of coronary bypass flow with color-Doppler and magnetic resonance imaging techniques: comparison with intraoperative flow measurements

OBJECTIVES

After coronary artery bypass surgery, patency and flow assessment is based on invasive methods such as angiography and intravascular ultrasound or flow wire techniques. The aim of the study was to compare intraoperative transit time flow measurements of coronary bypass grafts with early postoperative color-Doppler and MR-imaging assessment.

METHODS

In 22 patients (62+/-8.5 years) undergoing elective coronary bypass surgery the flow was measured in all internal mammary artery grafts (IMA) and saphenous vein grafts using the transit time flow technique. Postoperatively (days 5-7) all patients had a color-Doppler IMA graft assessment followed by a MR-angiography and flow measurement (navigator echo phase contrast technique with and without contrast bolus application) to determine patency and graft flow.

RESULTS

Data are expressed as the mean +/- SD). (1) In all patients the left IMA graft to the left anterior descending coronary artery (LAD) could be identified and flow could be assessed with both color-Doppler and MRI. Venous grafts could only be visualized by MRI. The use of an intravenous contrast bolus enhanced the visualization of coronary artery bypass grafts. (2) The mean IMA to LAD flow was 33+/-17 ml/min intraoperatively by transit time and postoperatively 36+/-25 ml/min by MR respectively 66+/-54 ml/min by color-Doppler technique. (3) The systolic/diastolic flow ratio was 0.44+/-0.12 intraoperatively and 0.43+/-0.17 postoperatively by MR respectively 0.67+/-1.0 by color-Doppler. (4) A statistically significant correlation could be demonstrated between intraoperative transit time and postoperative MR flow measurements (r = 0.57; P < 0.04), whereas the correlations to color-Doppler flow were poor. Postoperatively MR and color-Doppler showed a good correlation of systolic/diastolic flow ratio (r = 0.88; P < 0.008).

CONCLUSIONS

The color-Doppler method during echocardiography and MR-imaging are useful non-invasive techniques to visualize postoperative IMA grafts for patency assessment. The quantification of IMA flow is still difficult with either technique, but MR flow measurements showed the best correlation to the intraoperatively measured transit time flow. The MR technique is the most promising non-invasive method for postoperative evaluation of coronary bypass grafts, since it allows visualization and reliable flow quantification.

Isolated fracture of the ventricular septum after blunt chest trauma

Isolated rupture of of the ventricular septum after blunt chest trauma is a very rare traumatic affection. A 21-year-old man was admitted to our hospital because of blunt chest trauma and a forearm fracture. Initial echocardiography did not show any intracardiac or extracardiac pathologic lesions, but 12 hours later this examination was repeated because of the onset of a holosystolic murmur. An unusual traumatic rupture of the ventricular septum was demonstrated. The hemodynamically stable condition of the patient allowed surgical repair to be performed 3 months later.

Comparison of troponin-I and troponin-T after pediatric cardiovascular operation

BACKGROUND

Although the diagnostic value of troponin-T in childhood is documented, little is known about the significance of troponin-I. It was the aim of this study to compare the diagnostic value of troponin-I and troponin-T in children and newborns to assess the perioperative potential myocardial damage.

METHODS

Forty-eight children, mean, 51+/-54 months (mean value +/-1 standard deviation) (range, 1 day to 204 months) undergoing cardiac operation were prospectively enrolled in the present study. Troponin-I, troponin-T, creatine kinase (CK), and the MB isoenzyme were measured before operation and postoperatively within 2 days.

RESULTS

Postoperative values of troponin-I for children undergoing extracardiac operation were in the normal range. In children with interventions through the right atrium (n = 10) the mean value increase to 6.5+/-6.1 microg/L (range, 1.8 to 24.3 microg/L) and even to a mean of 29.9+/-21.1 microg/L (range, 7.5 to 90 microg/L) (p<0.01) in children with atrial and additional ventricular surgical approach (n = 23). Troponin-I was of equal specificity and sensitivity compared to troponin-T, excepted in patients with postoperative renal failure in whom troponin-T raised to false pathological results.

CONCLUSIONS

For detection of perioperative myocardial damage troponin-I shows a higher specificity than CK-MB activity and CK-MB mass. The diagnostic value of troponin-I is similar to troponin-T, but compared with troponin-T, it has the advantage of not being influenced by renal failure.

Long-term remission after resection, chemotherapy, and irradiation of a metastatic myxoma

Malignant local or metastatic myxomatous tumors of the heart are rare and sometimes present with an unpredictable outcome. The present report demonstrates an unusual case of left atrial myxoma with a rather strange distribution of metastases that had long-term remission after combined surgical resection, chemotherapy, and irradiation of cerebral and pulmonary metastases.