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H O Vetter

Publications and source records attributed to H O Vetter.

At least 19 recordsLinked to original sources
PubMed2003

Long-term effectiveness of operative procedures for Stanford type A aortic dissections.

BACKGROUND: To evaluate long-term effectiveness of strategies for managing the aortic root and distal aorta in type A dissections. METHODS: From 1990 to 1999, 50 patients (32 men, 64.07%; 18 women, 36.0%; mean age 57.4 y +/- 11.1) underwent operation for ascending aortic dissection. Surgical strategies included aortic root replacement with a composite graft (21/50; 42.0%), valve replacement with supracoronary ascending aortic graft (3/50, 6%), and valve preservation or repair (26/50; 52.0%). RESULTS: Overall hospital mortality rate was 18.0%. Follow-up was completed for 47 patients (94.0%) and ranged from 1 month to 10.5 years (mean 28.8 months). Actuarial survival for patients discharged from the hospital was 84% at 1 year, 75% at 5 years, and 66% at 10 years. There was no significant difference between the various procedures regarding mortality, neurological complications, long term survival and proximal re-operations. The ascending aorta alone was replaced in 8/50 patients (16%), ascending and hemiarch in 30/50 patients (60%) and arch and proximal descending aorta in 12/50 patients (24%) Hospital mortality (11.5, 20.0 and 16.7% respectively; p > 0.05) and 5- and 10-year survival (p > 0.05) were not statistically dependent on the extension of the resection distally. Residual distal dissection was not associated with a decrease in late survival. With regard to emergency surgery (36/50) there was no significant difference in hospital mortality (p > 0.05) and 5 year survival (p > 0.05) between those who had undergone coronary angiography (19/36; 52.8%) on the day of surgery with those who had not (17/36; 47.2%). CONCLUSIONS: Preservation or repair of the aortic valve can be recommended in the majority of patients with type A dissection. Distal extension of the resection does not increase surgical risk. Residual distal dissection does not decrease late survival. Preoperative coronary angiography may not affect survival in patients undergoing emergency surgery.

Adult↗
PubMed2002

Assessment of left mammary artery grafts (LIMA) to left anterior descending artery (LAD) after off-pump coronary artery bypass grafting by color Doppler.

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) on a beating heart with a LIMA graft to the LAD is established for patients with one vessel disease. The aim of the study was to assess the LIMA patency noninvasive by transcutaneous duplex ultrasound. METHODS: 25 patients (16 male, 9 female, mean age 58+/-13 yr) with LIMA grafts to LAD by OPCAB procedures were studied 7-20 days after surgery. Doppler velocity parameters were measured by use of a 7 MHz transducer placed in left intercostal space. The conventional coronary angiographies performed showed the LIMA graft patent. RESULTS: In all cases a typical biphasic pattern of blood flow was recorded with forward flow in both systole and diastole respectively. Under basal conditions the mean peak velocities in systole were 0.36 m/s and the mean peak velocities in diastole were 0.27 m/s with a mean systolic/diastolic ratio of 1.33. CONCLUSION: Transcutaneous Doppler ultrasound is useful in the detection of the LIMA graft flow. This non-invasive technique may find applications for routine postoperative follow-up of patients with LIMA grafts.

Aged↗
PubMed2001

Contrast-enhanced magnetic resonance angiography of mammary artery grafts after minimally invasive coronary bypass surgery.

BACKGROUND: The aim of the study was to investigate the application of the contrast-enhanced magnetic resonance angiography (CE-MRA) for the visualization of left internal mammary artery (LIMA) bypass. METHODS: A total of 30 patients with LIMA bypass (22 men, 8 women, 35 to 77 years) received a CE-MRA 4 to 20 days after surgery. The non-ECG-triggered CE-MRA was performed during expiration using a body array coil at a 1.5 Tesla scanner (Magnetom-Vision). A three-dimensional gradient-echo sequence with slice interpolation technique was applied. For the three-dimensional visualization, single coronal slices were postprocessed with maximal intensity projection. Of 30 patients 22 agreed to a comparative coronary angiography. RESULTS: Five bypasses were identified up to the end-to-side anastomosis. A total of 80% of the bypass course was detectable in 13 patients and 60% in 11 patients. In two LIMA bypasses only 30% of the proximal part could be viewed; one was found by conventional coronary angiography to be occluded. The other conventional coronary angiography showed the LIMA bypass to be patent. CONCLUSIONS: The complete course of the LIMA bypass to the left anterior descending coronary artery can be visualized by the MRA technique. The most reliable imaging of the distal anastomosis can be realized by reducing the negative influence of the beating heart.

Adult↗
PubMed2001

Surgical glove perforation in cardiac surgery.

BACKGROUND: Recently, concern for the protection of health care employees and health care recipients has led to increasing awareness of transmitted infections. Sterile surgical gloves were tested to determine the incidence of perforations after being worn during procedures commonly performed by cardiac surgeons. MATERIAL AND METHODS: In a prospective study conducted from January 15, 2000 through February 15, 2000, 953 gloves worn during cardiac surgery were evaluated for punctures. Pairs of sterile latex surgical gloves were collected over a period of one month. Routine tasks included mainly bypass and valve surgery. Impermeability was tested by means of a water retention test according to European standard EN 455 Part 1 performed on 954 (Manufix, Hartmann, Germany) latex gloves. A control group of 50 unused gloves was also evaluated for the presence of spontaneous leakage. Gloves were separated according to whether the wearer was an operator (254 gloves), first assistant (220 gloves), second assistant (272 gloves), or theatre nurse (207 gloves). Gloves with a known perforation occurring during the procedure were not included in the study. RESULTS: There were no punctures in the 50 unused gloves. Punctures were detected in 66 of 254 (26.0 %) gloves used by operators, 49 of 220 (22.3 %) used by first assistants, 25 of 272 (9.2 %) used by second assistants, and 78 of 207 (37.7 %) used by theatre nurses. Some gloves had more than one puncture, accounting for the 244 holes detected (operators 75/244 = 30.7 %; first assistants 54/244 = 22.1 %; second assistants 28/244 = 11.5 %; theatre nurses 87/244 = 35.7 %). Sites of scalpel and suture needle injuries were most commonly the thumb (27.3 %) and pointer finger (42.1 %) of the non-dominant hand, followed by, in descending order: middle finger (10.2 %), other fingers (15.7 %), palm (3.8 %) and back of the hand (0.9 %). CONCLUSION: The number of punctures that occur during cardiac operations is obviously higher than has so far been assumed. Therefore, cardiac surgeons should consider the incidence of unknown glove perforations when planning surgery in patients with infectious diseases.

Cardiac Surgical Procedures↗
PubMed2001

Cardiomyoplasty: long-term results in ischemic cardiomyopathy.

INTRODUCTION: Cardiomyoplasty was introduced into clinical practice in 1985 by Alain Carpentier. Since then, the procedure has been performed on more than 400 patients worldwide. The latissimus dorsi muscle is prepared maintaining the vascular supply, then the muscle flap is wrapped around the heart and connected to a cardiomyostimulator. The muscle is later stimulated synchronously with ventricular systole to augment the cardiac contractility. METHODS: To evaluate the long-term outcome of cardiomyoplasty, we investigated 3 patients electively undergoing this procedure in our hospital. All of these patients (2 male, 1 female) had severe chronic heart failure which did not respond to optimal medical treatment. The mean follow-up time was 42 months (range 24 - 60). All patients showed symptoms corresponding to NYHA class III, and one patient intermittently showed class IV despite conventional medical therapy. Patients were evaluated at 6-month intervals for 2 years with right heart catheterization, radionuclide scans, echocardiography, as well as questionnaires for assessing quality of life. RESULTS: There was no operative mortality. One patient experienced sudden death 2 years after operation. There were no significant changes in hemodynamic variables at 6, 12 or 24 months after surgery, respectively. Left ventricular ejection fraction increased from 20.0 ( 9.2 to 40.0 +/- 7.1 % (p = 0.05) 1 year after operation. Considerable improvement of symptoms was seen in all, and 1 patient returned to work. NYHA-class decreased from 3.1 to 2.0 (p = 0.02). CONCLUSIONS: Following cardiomyoplasty, patients may exhibit impressive clinical improvement with less striking changes of objective hemodynamic parameters. Thus, in our patients, dynamic cardiomyoplasty improves quality of life. We do not consider this treatment to be an alternative to heart transplantation. It does, however, provide a therapeutic option for patients for whom transplantation is contraindicated.

Cardiomyoplasty↗
PubMed1999

Evaluation of a new continuous thermodilution cardiac output monitor in cardiac surgical patients: a prospective criterion standard study.

OBJECTIVE: To evaluate the accuracy of a new continuous cardiac output monitor in critically ill patients. DESIGN: Criterion standard study. SETTING: Cardiac surgery intensive care unit in a university hospital. PATIENTS: Twenty cardiac surgical patients requiring intensive care treatment with pulmonary artery catheters after surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cardiac output was monitored continuously with a modified pulmonary artery catheter that has a heating filament on the outside of the catheter. Four modes of data processing with different response times ("Normal," "Fast," "FastFilter," and "Urgent" modes) used by the monitoring system. A total of 240 determinations of cardiac output were performed using conventional bolus thermodilution technique; these results were compared with those obtained using three of the four continuous measuring modes available ("Normal," "FastFilter," and "Urgent"). Cardiac output ranged from 3.47 to 15.77 L/min (bolus thermodilution). The mean (bias) +/- SD of differences (precision) for all measurements was 0.40+/-1.26 L/min in the Normal mode (cardiac output <10 L/min: 0.34+/-0.66 L/min), 0.53+/-1.27 L/min in the FastFilter-mode (cardiac output <10 L/min: 0.60+/-0.75 L/min), and 0.63+/-1.34 L/min in the Urgent mode (cardiac output <10 L/min: 0.57+/-0.82 L/min). CONCLUSIONS: Continuous cardiac output measurement using the thermodilution technique is reasonably accurate, reliable, and applicable in routine clinical practice. The values obtained using the Normal mode of the monitor agreed significantly better with the conventional thermodilution method than the results of the two other modes studied (FastFilter and Urgent). In addition, measurements in two patients with cardiac output values of >10 L/min did not agree with the results of the bolus thermodilution method.

Adult↗
PubMed1998

Procalcitonin as a marker of systemic inflammation after conventional or minimally invasive coronary artery bypass grafting.

Cardiac surgery using cardiopulmonary bypass (CPB) often induces a systemic inflammatory response syndrome (SIRS). The concept of minimally invasive direct coronary artery bypass (MIDCAB) eliminates cardiopulmonary bypass. We evaluated the perioperative time course of procalcitonin (PCT) to compare the inflammatory response due to these two different surgical procedures. 57 patients were studied: CABG with CPB (n = 30), MIDCAB without CPB (n = 27). The following data were measured preoperatively, after induction of anesthesia, after separation from CPB in the CABG group or after left internal mammary artery (LIMA)-to-left anterior descending artery (LAD) anastomosis in MIDCAB group, and every 3 hours for the first 42 hours in the ICU: PCT, C-reactive protein (CRP), body temperature, hemodynamic parameters, and the need for catecholamines. Leucocyte counts were measured daily. For statistical analyses the Friedmann, Wilcoxon, or Mann-Whitney U tests were used. PCT in the CABG group rose to a maximum of 2.0 ng/ml (median) at 15 hrs postoperatively. In the MIDCAB group maximal PCT concentration was 0.7ng/ml (median) (p < 0.05). CRP was elevated to 17.1 mg/dl in the CABG and 18.5mg/dl in the MIDCAB group (n.s.). The leucocyte counts were increased on day 2 in the CABG group (p < 0.05). In the CABG group about 25% of the patients needed noradrenaline, but in the MIDCAB group none (p < 0.05). Body temperature did not differ between both groups. The increase in PCT concentration was more pronounced after CABG, indicating a reduced inflammatory response after MIDCAB. CRP was increased after both procedures. PCT reflects the inflammatory response after cardiac bypass surgery with or without CPB.

Aged↗
PubMed1997

Improvement of heart-, lung-, and liver-performance during mechanical circulatory support by the Novacor-system.

OBJECTIVE: Since its clinical introduction, the Novacor left ventricular assist system (LVAS) has proved to be a reliable and safe method for bridging to cardiac transplantation. To find out whether univentricular assistance is sufficient in patients with severe global heart failure, multi organ monitoring using the COLD system was performed. METHODS: In seven patients (mean age 38.8 years), the wearable Novacor system N100 was implanted. Preoperatively, during the first 72 h thereafter and before heart transplantation right and left ventricular cardiac output, right ventricular ejection fraction, pulmonary-, intrathoracic-and total blood volume, extravascular lung water and excretory liver function were monitored by means of double indicator dilution technique with the COLD system. Conventional hemodynamic parameters have also been documented. RESULTS: During left ventricular assistance, both pulmonary and systemic arterial cardiac outputs increased significantly (Student's t-test, P < 0.05). Right ventricular ejection fraction rose from 17 to 26%, preoperatively elevated pulmonary and intrathoracic blood volumes and extravascular lung water fell significantly to normal ranges. Total blood volume remained constant, excretory liver function improved markedly. CONCLUSIONS: Pulmonary cardiac output improves due to the reduced right ventricular afterload by unloading the impaired left ventricle with the Novacor pump. The drop in pulmonary blood volume, intrathoracic blood volume and extravascular lung water also indicates a decrease of pulmonary congestion. Since total blood volume remains unchanged, a volume shift to the systemic circulation is suggested, resulting in an improved splanchnic perfusion as demonstrated by a better excretory liver function. In the absence of primary pulmonary hypertension, treatment of global heart failure with a left ventricular assist device is possible. The COLD system is a useful tool for managing this patient group during the postoperative period.

Adult↗
PubMed1997

Platelet morphology in patients with mechanical circulatory support.

OBJECTIVE: Mechanical circulatory support is a therapy for patients with end stage cardiac insufficiency. The thromboembolic events are feared complications during support, due to the surface thrombogenicity of the implanted device. Activated blood platelets play a major role in this context. Consequently the platelet morphology of patients was investigated. METHODS: Platelets of eight patients were observed by means of scanning electron microscopy during the period of support with the Novacor left ventricular assist system N100. Blood was collected preoperatively and daily during the first week as well as weekly during the first 3 months. Samples were fixed with cacodylic-acid buffered glutaraldehyde. Platelet alterations were classified as non-activated, activated and aggregated, based on the so-called 'shape change' morphology. In addition, blood coagulation parameters were evaluated (e.g. activated partial thromboplastin time, prothrombin time, antithrombin III). RESULTS: Preoperatively, 15.0 +/- 4.6% (overall mean values) of activated platelets were found. Within the first postoperative week, the mean level of activated platelets increased to 32.8 +/- 8.0% (P < 0.05). Comparing short- (< 30 days; n = 4) vs. long-period (> 30 days; n = 4) support, a significant difference of activated platelets was evaluated (24.3 +/- 3.3% vs. 34.8 +/- 3.4%, P = 0.004). A correlation was found between the values of activated clotting time and activated platelets. Specific platelet deformations and damages appeared during support, which could not be found preoperatively. CONCLUSIONS: The platelet morphology showed alterations in all patients probably most strongly induced by the surface activation of the implanted device. These observations should be taken into consideration in management of postoperative anticoagulation therapy.

Adult↗
PubMed1997

Surgical therapy for coronary artery disease in patients with a left ventricular ejection fraction of 25% or less.

BACKGROUND: In patients with advanced coronary artery disease (CAD) and markedly decreased left ventricular ejection fraction (EF) symptoms of myocardial ischemia and insufficiency may be complicated by ventricular arrhythmias. Appropriate surgical therapy must be tailored to the individual symptoms. The aim of this study was to compare the different current methods. METHODS: From 9/1990 to 9/1994 138 patients with coronary artery disease and a left ventricular EF of < or = 25% were operated. Patients with dominating Angina pectoris and vital myocardium were revascularized (ACB; n = 17); two of these patients were 12 and 37 months p.o. transplanted. Because of dominating dyspnea, diffuse CAD and missing AP heart transplantation seemed indicated (HTX; n = 102). In two of these patients ventricular assist devices were implanted as a bridge to transplantation; both patients survived. Patients with malign tachycardias received either an implantable cardio-defibrillator (ICD; n = 16) or had arrhythmia surgery (ARS; n = 3). Patients of the HTX-Group were younger (54 vs 60 years; p < 0.05), had more often previous surgery (28% vs 20%) and were in worse conditions (NYHA 3.5 vs 3.0; p < 0.05). RESULTS: The main cause of death after transplantation was multi-organ failure (MOF; 14/102; 13.8%). The best long-term survival (87% after 3.2 years, p < 0.01 vs HTX)-with low average functional classes (NYHA 2.9)-had the patients after ICD implantation. The best quality of live (NYHA 1.1; p < 0.01 vs ICD)-associated with a high mortality due to preoperatively impaired organ-systems (62% operative survival, 57% 4-years survival)-was achieved by transplantation. In patients with a history of ventricular arrhythmias, who are waiting for a transplantation, the implantation of an ICD should be considered. Bypass surgery as well as arrhythmia surgery showed good survival (1-year survival 82% and 66% respectively) and functional results (NYHA 1.7 and 1.5 respectively).

Arrhythmias, Cardiac↗
PubMed1996

Haemodynamic and echocardiographic characteristics of a stentless allograft mitral prosthesis: an in vitro study.

Poor long-term durability and impaired haemodynamic performance are known disadvantages of bioprosthetic heart valves when compared to valve replacement using aortic allografts. A new stentless allograft mitral implant was developed and tested in vitro in a left ventricular model and pulsatile flow system to evaluate hydrodynamic function. Mitral valves were excised from sheep hearts and the mitral annulus reinforced by a strip of ovine pericardium. A patch of expanded polytetrafluoroethylene (ePTFE) was placed above the tips of the remaining papillary muscles. For in vitro evaluation of a total of five valves were investigated in a pulse duplicator. Transvalvular pressure gradients (delta P) were measured over a flow range corresponding to a cardiac output of 5l/min, at a heart rate of 70 beats/min, with a systole accounting for approximately 35% of the cardiac cycle. The systolic ejection period and diastolic filling period in this model were 350 and 510 ms, respectively, and aortic pressure was 120/80 mmHg. The effective orifice area was calculated from measurements of mean pressure drop and root mean square flow. Additionally, valve performance was evaluated by Doppler echocardiography. Results of in vitro studies of a 25 mm stentless allograft mitral implant, which is similar to the valves implanted in a chronic weaning sheep model, revealed a mean(s.d.) delta P of 2.0(1.6) mmHg (range 1.0-4.9 mmHg). The mean calculated effective orifice area was 3.38(0.52) cm(2) (range 2.5-3.8 cm(2)). Doppler echocardiography showed excellent performance of the mitral valve components and valve competence could be achieved. During the in vitro studies no failure caused by tissue rupture was detected. The results of the in vitro studies revealed data for delta P and effective orifice area superior to data obtained for standard 25 mm porcine bioprostheses.

Animals↗
PubMed1995

Experience with the Novacor left ventricular assist system as a bridge to cardiac transplantation, including the new wearable system.

The three components of the Novacor left ventricular assist system, compact controller, battery, and back-up battery, have been miniaturized in the development of the wearable system. Therefore patients can be fully mobilized receiving mechanical circulatory support while awaiting heart transplantation. Between February 1992 and April 1994 a total of eight patients with decompensated heart failure (6 dilated cardiomyopathy, 1 acute myocarditis, 1 ischemic cardiomyopathy) were treated with the Novacor left ventricular assist systems. In the most recent four cases the wearable system (N100P) was used. Patients' ages ranged from 17 to 49 years. In five patients severe failure of the right side of the heart was present at the time of implantation. Hemodynamic stabilization was achieved in all patients during the 2 to 122 days (mean 30.8 +/- 42.5 days) of support. The following parameters were measured on average before and 24 hours after implantation of the left ventricular assist system: mean arterial pressure 70 +/- 11 versus 87 +/- 13 mm Hg (p < 0.05), cardiac index 1.71 +/- 0.42 versus 3.23 +/- 0.74 L/min/m2 (p < 0.05), pulmonary capillary wedge pressure 27.1 +/- 4.4 versus 9.9 +/- 5.2 mm Hg (p < 0.01), mean pulmonary pressure 41 +/- 9 versus 27 +/- 6 mm Hg (p < 0.05), and right ventricular ejection fraction 16.7% +/- 10.3% versus 22.0% +/- 11.6% (not significant). Patients who received the wearable system were capable of managing their own power supply during the bridging period and were able to walk to the hospital park and shopping area. One patient had a serious pulmonary infection, which was treated successfully, and two patients had a cerebrovascular accident, which resolved in one and resulted in a minor residual deficit in the other. All eight patients received a heart transplant. One patient died early after transplantation and seven patients are alive and well. In summary, the wearable Novacor left ventricular assist system provides major advantages regarding quality of life of patients during mechanical circulatory support. However, there is a remaining risk of thromboembolism despite anticoagulation therapy.

Adolescent↗
PubMed1995

Comparison of porcine biological valves with pericardial valves--a 12-year clinical experience with 1123 bio-prostheses.

In order to evaluate selective differences of biological porcine valves versus pericardial valves and to analyze various valve models, 8 different bioprostheses (4 porcine valves, 4 pericardial valves) were studied in a 12-year follow-up. From 1978 to 1990, 476 porcine bioprostheses (Carpentier-Edwards: n = 104, Carpentier Edwards Supraanular: n = 59, Hancock I: n = 41, Hancock II: n = 272) and 647 pericardial valves (Hancock-Extracorporeal: n = 479, Ionescu-Shiley: n = 76, Carpentier-Edwards: n = 57, Mitroflow: n = 35) were implanted. At time of implantation, the patient age ranged from 21-85 years, mean 57.1 +/- 12.4 years. 831 patients were analyzed in the long-term follow-up (62.3 +/- 18.6 months, cumulative follow-up of 6632 patient-years). The incidences of thromboembolic complications (TE), endocarditis (E), primary tissue failure (PTF), rate of reoperation (ReOp), and late mortality due to prosthesis dysfunction were analyzed, calculated, and compared within the different valve models (actuarial data, chi 2 test, log rank analysis). The incidences of TE and E were lower for pericardial valves when compared with porcine bioprostheses (TE: 0.88 vs. 1.8%/patient year; E: 0.24 vs. 0.5%/patient year); within the 2 groups, the different valve models did not show any major differences. However, the incidence of PTF was significantly higher in the pericardial valve group, being 36 +/- 6.5%, 68 +/- 10% and 86 +/- 19.5% after 6, 8, and 10 years; the respective figures for the porcine valves were 6 +/- 3.5%, 18 +/- 7.1%, and 60 +/- 13.1% (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Mitral allograft with chordal support: echocardiographic evaluation in sheep.

The in vivo echocardiographic behavior of a new mitral allograft design that incorporates ePTFE patches and chordae to enhance durability has been evaluated in sheep. A strip of pericardium was sewn around the anulus margin and an ePTFE patch of 0.4 mm thickness placed over the truncated papillary muscle tip. In four out of ten cases, 5/0 ePTFE sutures were used additionally to reinforce the native chordae of the anterior leaflet. The allografts were cold-stored at 4 degrees C after antibiotic treatment and implanted in weanling sheep. Valvular function was first examined intraoperatively by transesophageal echocardiography and again after a mean follow up of 153 +/- 8 days by epicardial echo. In all six long term survivors, valve motion was unimpaired and similar to that of the natural mitral valve. There was sufficient coaptation and concentric opening action of the leaflets. Ventricular contraction was enhanced by maintaining the annulo-ventricular connection of the native valve. Color and pulsed Doppler revealed a physiologic biphasic flow pattern and only minor regurgitation in one case. Mean transvalvular pressure gradient was 3.3 +/- 2.1 mmHg on average which correlates well with values obtained from subsequent cardiac catheterization. In conclusion, this new design of a mitral allograft shows excellent in vivo echocardiographic behavior after five months of implantation. Therefore, human allografts of this type could be recommended for clinical application.

Animals↗
PubMed1994

Heart-lung transplantation in a patient with pulmonary atresia and ventricular septal defect.

Operation for pulmonary atresia and ventricular septal defect is challenging, as in most patients the pulmonary arteries are hypoplastic, nonconfluent, or in part absent. In these cases, combined heart-lung transplantation may be the surgical treatment of choice. In the described case, the morphology of pulmonary atresia and ventricular septal defect was present in combination with completely atretic main, left, and right pulmonary arteries. In this patient, successful heart-lung transplantation was performed.

Adult↗