Florian M. Wagner

Port-Access Coronary Artery Bypass Grafting With the Use of Cardiopulmonary Bypass and Cardioplegic Arrest ☆

BACKGROUNDnTo reduce surgical trauma, we performed minimally invasive Port-Access (Heartport Inc, Redwood City, CA) coronary artery bypass grafting with cardiopulmonary bypass and cardioplegic arrest.nnnMETHODSnThirty-six men and 6 women with a median age of 59 years (range, 31 to 75 years) and isolated lesions of the left anterior descending branch of the coronary artery underwent Port-Access coronary artery bypass grafting. A small (6- to 9-cm) incision was made parasternally on top of the fourth rib. The left internal thoracic (mammary) artery was dissected and taken down through the minithoracotomy either alone or using an additional thoracoscopic approach. Cardiopulmonary bypass was instituted through femoral cannulation, and an additional endoarterial balloon catheter (Heartport Inc) was introduced into the ascending aorta for aortic occlusion, aortic root venting, and the delivery of cold antegrade crystalloid cardioplegia. After cardioplegic arrest, the left internal mammary artery was anastomosed to the left anterior descending artery under direct vision.nnnRESULTSnThe median left internal mammary artery takedown time was 49.5 +/- 21.9 minutes, the duration of cardiopulmonary bypass was 59.5 +/- 32.8 minutes, the aortic occlusion time was 28.5 +/- 7.9 minutes, the intensive care unit stay was 1.0 +/- 3.2 days, and the total hospital stay was 5.0 +/- 2.5 days. Intraoperative angiograms were done in the first 10 patients and showed patent left internal mammary artery grafts without anastomotic complications in all cases. Two arterial dissections, including one aortic dissection, were observed in patients with preexisting peripheral vascular disease. The other complications were minor. All but 1 patient recovered well, with no major limitations in their daily activities.nnnCONCLUSIONSnUsing this minimally invasive method, sternotomy-related complications can be avoided, the hospital stay can be reduced, and a safe coronary artery bypass grafting procedure can be performed with the advantage of cardiopulmonary bypass and cardioplegic arrest as are used routinely in conventional coronary artery operations.

New telemetric system for daily pulmonary function surveillance of lung transplant recipients

BACKGROUNDnFollowing lung transplantation, prompt diagnosis and therapy of acute pulmonary rejection and infection episodes relies primarily upon changes in pulmonary function and determines long-term outcome. We tested a new system that allows daily monitoring of the patients pulmonary status even after discharge from the hospital.nnnMETHODSnSeven lung transplant recipients from our center were equipped with a telemetric monitoring device consisting of a portable flowmeter and a special modem unit. The flowmeter measures forced vital capacity (FVC), forced expiratory volume per second (FEV1), and mid expiratory flows (MEFs), encodes information like fever, cough, and dyspnea in a binary code form, and stores all values in a 32 kB memory unit. After its use, the patient positions the flowmeter onto the modem unit which automatically connects to a central computer at our center to transfer all saved data. The whole set can be used via any regular phone jack. The patients file in the computer can be checked every day.nnnRESULTSnAll patients learned to use the unit during their postoperative stay or during later follow-up, and were able to apply the system at home. In a mean follow-up period of 10.3+/-2.2 months, 15 episodes of significant deterioration in home pulmonary function tests (PFTs) (>10%) were registered in 6 patients, which were all confirmed by in-hospital body plethysmography. They resulted in diagnoses of 4 episodes of acute rejection, 6 cases of beginning bacterial pneumonia, and 5 cases of, most likely, viral tracheobronchitis. Only 1 patient had to be admitted to the hospital. All patients PFTs returned to previous values after treatment.nnnCONCLUSIONSnTelemetric monitoring of graft function in lung transplant recipients allows reliable early diagnosis and treatment of infection or rejection, which might help to prevent exacerbation of the pathology and reduce quantity of amounting graft dysfunction.

Minimally Invasive Surgical Technique for the Treatment of Multivessel Coronary Artery Disease

BACKGROUNDnTo avoid sternotomy-related complications after cardiac operations, we developed a minimally invasive surgical technique for the treatment of multivessel coronary artery disease.nnnMETHODSnFrom November 1996 to May 1997, 39 patients (age range, 50 to 78 years) with coronary artery disease were treated with the use of this technique. Through a small (6- to 9-cm) left lateral chest incision in the third intercostal space, the left internal mammary artery was harvested directly. With the use of cardiopulmonary bypass and cardioplegic arrest in all patients except 1, the left internal mammary artery was anastomosed to the left anterior descending artery. In addition, vein grafts and other arterial conduits were used for revascularization of the other coronary arteries.nnnRESULTSnThere were no intraoperative complications. All the patients survived the procedure and had an uneventful postoperative course. Wound complications occurred in 2 patients. The median (+/- standard error of the mean) hospital stay was 6 +/- 1 days.nnnCONCLUSIONSnThis technique combines minimally invasive surgical conditions with the safety standards of routine cardiac operations. With the use of this approach, even extensive coronary artery disease can be treated.

Do vitamins C and E attenuate the effects of reactive oxygen species during pulmonary reperfusion and thereby prevent injury

BACKGROUNDnWe established an in vivo pig model of standardized lung ischemia to analyze pulmonary reperfusion injury. Enhanced chemiluminescence measurement (CM) allowed immediate quantification of reactive oxygen species (ROS) and subsequent lipid peroxidation. In such model we analyzed efficacy of vitamins C and E to prevent reperfusion injury.nnnMETHODSnAfter left lateral thoracotomy in group I (n = 6), normothermic lung ischemia was maintained for 90 minutes followed by a 5-hour reperfusion period. In group II, animals (n = 6) underwent ischemia as in group I, but received vitamins (preoperative IV bolus C = 1 g, E = 0.75 g, then continuous infusion (125 mg/h) each throughout the study). In Group III, animals (n = 6) underwent sham surgery and served as controls. Hemodynamic variables and gas exchange were assessed. The CM was performed for injury quantification in blood samples and to determine activation of isolated PMNs. The Wilcox rank test was used for statistical analysis.nnnRESULTSnDuring reperfusion, all animals in group I developed significant pulmonary edema with significant loss of pulmonary function. The addition of vitamins (group II) improved oxygenation and almost abolished pulmonary inflammatory cell infiltration; however, as in group I, pulmonary compliance still tended to decline and the number of circulating leucocytes increased. The CM showed that, compared with group I, vitamins reduced O2- basic release by PMNs significantly (460% to 170%, p < 0.05; control 165%), but could not prevent an increase of free ROS in whole blood similar to group I (443% to 270%, p = ns, control 207%). With regard to lipid peroxidation only a trend of reduction was observed (117% to 105%, p = ns, control 100%).nnnCONCLUSIONSnDifferentiated analysis by CM demonstrated that vitamins C and E inhibited PMN activation but were not able to prevent radical production by other sources. This offers a potential explanation why radical scavengers like vitamins only attenuate but ultimately do not prevent reperfusion injury.

Clinical experiences with minimally invasive mitral valve surgery using a simplified port accessTM technique

OBJECTIVEnUsing the initial experiences with the Port-Access technique for the treatment of mitral valve disease some changes were made thus resulting in more simple and faster procedures.nnnMETHODSnTwenty-nine patients (13 male, 16 female, aged 30 to 75 years, median 62.5 +/- 11.0 years) underwent minimally invasive mitral valve surgery between May 1996 and December 1997. The underlying diseases were: mitral valve insufficiency (n = 16), mitral valve stenosis (n = 7) and combined mitral valve disease (n = 6). Through a small right thoracotomy (5-7 cm) access to the pericardium and the heart was gained. Cardiopulmonary bypass was instituted through femoral cannulation and an intraaortic balloon-catheter was introduced for aortic occlusion, aortic root venting and delivery of cold crystalloid cardioplegia. Mitral valve repair (five patients) or replacement (24 patients) was performed.nnnRESULTSnThere was no death during the whole follow-up period. There was no perivalvular leak and only minor residual mitral valve regurgitation was observed on intraoperative or postoperative (3 months) transesophageal echocardiography in three patients. There was no postoperative study-related complication. Time of ventilation and intensive care unit were comparable with the data of patients undergoing conventional mitral valve surgery but hospital stay was shorter in the last 10 consecutive cases.nnnCONCLUSIONSnThis simplified technique of mitral valve surgery combines the advantage of less invasive operative and good cosmetic results with the safety of conventional mitral valve surgery. At our institution this technique presents in well selected patients suffering from mitral valve disease the procedure of choice.

The Dresden approach for complete multivessel revascularization

BACKGROUNDnIn a prospective clinical trial, a group of patients receiving less invasive surgical procedure, including minithoracotomy in combination with cardiopulmonary bypass (group 1), was compared to a group of patients receiving conventional bypass surgery (group 2) for the treatment of coronary artery disease.nnnMETHODSnGroup 1 included 85 patients (71 men, 14 women, aged 39 to 82 years, median 61.1 +/- 9.0 years); group 2 included 53 patients (38 men, 15 women, aged 51 to 79 years, median 62.0 +/- 6.1 years).nnnRESULTSnThere were no perioperative deaths in the whole series of patients. Time of operation was 256 +/- 43 minutes in group 1 and 150.0 +/- 53.6 minutes in group 2. Hospitalization was 6.0 +/- 1.4 days and intensive care unit stay 1 day for both groups. Back pain assessment on postoperative day 3 showed less pain in group 1. Three-month follow-up revealed ischemia in stress electrocardiogram in 2 patients (2.5%) in group 1 and in 2 patients (4.1%) in group 2. Coronary angiograms confirmed the stress-electrocardiogram findings.nnnCONCLUSIONSnSurgical results are equal for both techniques. Even though time of operation is longer in patients receiving less invasive procedures, intensive care unit stay and hospital stays are the same length. Early postoperative back pain is less in group 1 and combined with faster convalescence.

Minimally invasive mitral valve surgery – clinical experiences with a PortAccess system

OBJECTIVEnThis is the initial experience with a new minimally invasive surgical technique for the treatment of mitral valve disease using a PortAccess system.nnnMETHODSnBetween May 1996 and May 1997, 21 patients (nine male, 12 female, aged 30-75 years, median 64 years) underwent minimally invasive mitral valve surgery. The underlying diseases were: mitral valve insufficiency (n = 11), mitral valve stenosis (n = 5) and combined mitral valve disease (n = 5). Through a small right thoracotomy (6-8 cm) access to the pericardium and the heart was gained. Cardiopulmonary bypass was instituted through femoral cannulation and an intraaortic balloon-catheter (Heartport Inc., Redwood City, CA) was introduced for aortic occlusion, aortic root venting and delivery of cold crystalloid cardioplegia. Mitral valve repair (four patients) or replacement (15 patients) was performed.nnnRESULTSnThere was no death during the whole follow-up period. There was no perivalvular leak and only minor residual mitral valve regurgitation was observed on intraoperative or postoperative (3 months) transesophageal echocardiography. There was no postoperative study-related complication. Time of ventilation, intensive care unit and hospital-stay were comparable with the data of patients undergoing conventional mitral valve surgery.nnnCONCLUSIONSnThis technique of PortAccess mitral valve surgery combines the advantage of less invasive operative trauma with the safety of conventional mitral valve surgery.

Clinical Experience with Minimally Invasive Coronary Artery and Mitral Valve Surgery with the Advantage of Cardiopulmonary Bypass and Cardioplegic Arrest Using the Port Access Technique

Abstract. To minimize surgical trauma, the use of Port Access cardiac surgery was initiated in patients (pts) with coronary artery disease (CAD) (42 pts) or mitral valve disease (MVD) (24 pts) in March 1996 at our institution. Altogether 42 pts (36 men, 6 women; age 31–75 years, median 59.0 years) with isolated lesions of the left anterior descending (LAD) artery underwent Port Access coronary artery surgery (PACAS). A small (5–9 cm) incision was done parasternally on top on the fourth rib. The left internal mammary artery (LIMA) was dissected through the minithoracotomy or by using an additional thoracoscopic approach. A total of 24 pts (12 men, 12 women; age 30–75 years, median 62 years) underwent Port Access mitral valve surgery (PAMVS). In these pts the procedure was performed through a small right thoracotomy (6–8 cm). In all cases, endovascular cardiopulmonary bypass (CPB) was instituted through femoral cannulation, and an additional endoaortic balloon catheter was introduced into the ascending aorta for aortic occlusion. In pts with PACAS the survival was 98% (41/42) and in the PAMVS group 100%. All pts but one survived the PACAS and are well today. There were no deaths in the PAMVS group. The hospital stay was reduced by 1 day on average after PACAS and 3 days after PAMVS. Thus in well selected patients Port Access cardiac surgery represents a safe and feasible minimally invasive surgical approach that avoids the potential complications of a sternotomy while offering the advantages and safety of CPB and cardioplegic arrest. This minimally invasive approach offers a shortened hospital stay and earlier rehabilitation.

New minimally invasive surgical technique using arterial T-grafts for treatment of double-vessel coronary artery disease: experimental study.

Abstract. Minimally invasive surgery has been used successfully in patients with single-vessel coronary artery disease (CAD), but there are no clinical reports of surgical techniques for the treatment of multivessel disease in this field using both internal mammary arteries (IMAs). Therefore a canine model has been established to demonstrate the feasibility of a minimally invasive surgical treatment of coronary artery double-vessel disease using both IMAs. Ten mongrel dogs underwent bilateral thoracoscopic preparation of both internal mammary arteries through small left lateral chest ports. Using the Port Access endovascular cardiopulmonary bypass system the right IMA (RIMA) was anastomosed as a free graft end-to-side to the left IMA (LIMA) as a T-graft. After induction of cardioplegic arrest the RIMA was anastomosed to the circumflex artery and the LIMA to the left anterior descending artery. All animals were weaned from cardiopulmonary bypass without inotropic support. The electrocardiogram showed sinus rhythm with no signs of ischemia. Intraoperative coronary angiography demonstrated patency of all anastomoses. The minimally invasive surgical treatment of double-vessel CAD using arterial T-grafts of both IMAs is thus feasible. Surgical trauma can be further reduced by harvesting the RIMA transmediastinally through the left lateral chest.

Minimal invasive chirurgische Versorgung der koronaren Zweigefäß-Erkrankung im Tiermodell — eine experimentelle Studie

Wie in anderen chirurgischen Disziplinen sind auch in der Herzchirurgie minimal invasive Verfahren zur Behandlung von einzelnen Herzerkrankungen erfolgreich eingefuhrt worden. Neben der Behandlung von Herzklappenerkrankungen ist die Chirurgie der koronaren Herzkrankheit ein Schwerpunkt der minimal invasiven Technik. Bisher ist es gelungen, die koronare Eingefas-Erkrankung erfolgreich zu behandeln. Ausgedehntere Krankheitsstadien, wie die Zweigefas- und die Dreigefas-Erkrankung sind bisher fur die minimal invasive Technik nicht erschlossen worden. In der vorliegenden experimentellen Studie wurde eine neuartige Technik entwickelt, bei der unter dem Schutz der extrakorporalen Zirkulation (EKZ) und unter Anwendung des kardioplegischen Herzstillstandes, den Standardbedingungen konventioneller Herzchirurgie, die koronare Zweigefas-Erkrankung behandelt wurde.