[Parameters of quality for aortic valve replacement]. / Qualitätsparameter für den Aortenklappenersatz.

Advantages and disadvantages of mechanical or biological heart valve prostheses in combination with complications during long-term follow-up are responsible for the quality of aortic valve replacement. Anatomical conditions like narrow aortic root, concomitant coronary artery disease or reduced left ventricular function impair the quite good surgical results necessitating surgical intervention or the use of stentless valve implants.

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.

[Atrial lead placement in cases of intraoperative atrial fibrillation]. / Vorhofsondenplatzierung bei Patienten mit Vorhofflimmern.

AIM: Evaluating the efficiency of a prescribed concept for atrial lead placement in cases of intraoperative atrial fibrillation (AF). METHODS: Over the period from 11/1998 to 5/2000, we carried out a prospective study on 40 patients with AF. After implantation of the screw electrode into the lateral wall of the atrium, an amplitude of the intracardial ECG of > or = 1.4 mV was arbitrarily defined as tolerable. At amplitudes of < 1.4 mV, atrial overdrive-stimulation occurred at 400 to 800 ppm in order to convert the AF to sinus rhythm (SR). Following successful overdrive-stimulation, the atrial electrode was positioned according to standard values (P-wave > 3 mV, pacing threshold < 0.5 V at 0.5 ms). In the case of unsuccessful intraoperative atrial stimulation, the electrode was repositioned until an amplitude of > or = 1.4 mV was reached. In all cases bipolar atrial screw electrodes (Model 4068, Medtronic Inc., Minneapolis, MN, USA) were implanted. The intraoperative measurements were carried out via the atrial channel of a 5311 PSA (Medtronic Inc., Minneapolis, MN, USA). In follow-up after 6 weeks, the atrial stimulation threshold was measured in [V] at 0.5 ms and the signal amplitude of the P-wave in [mV], or in the case of AF detection with successful mode switch activation. RESULTS: In 31/40 patients (77.5 %) with intraoperative persistent AF, fibrillation amplitudes of 1.4 to 3.1 mV (mean value 1.9 +/- 0.4 mV) were measured. In 9/40 patients (22.5 %) with intraoperative AF, 4 cases of conversion to SR using burst stimulation were documented. Atrial lead placement was performed using standard values. After 6 weeks, 33/40 patients (82.5 %) had SR, while intermittent AF episodes with successful mode switch activation were documented in 21 patients (52.5 %). The P-wave amplitude was 3.63 +/- 0.69 mV (range 1.8 to 4.9 mV), the atrial stimulation threshold was 1.3 +/- 0.4 mV (range 0.4 to 1.9 mV). Atrial lead adjustment due to sensing defects was not required for any patients. CONCLUSION: The results show that all atrial leads implanted in accordance with this concept demonstrate proper sensing at SR as well as under AF, with successful mode switch episodes and acceptable stimulation thresholds.

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.

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.

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.

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.

[Patient-controlled analgesia (PCA) for postoperative pain relief. A prospective observational study for evaluating the technology in a ward routine]. / Patientenkontrollierte Analgesie (PCA) zur postoperativen Schmerztherapie. Eine prospektive Beobachtungsstudie zur Technologiebewertung im Stationsbetrieb.

Patient-controlled analgesia (PCA) is rarely used on surgical wards despite described advantages of this method as compared to conventional techniques. Uncertainties in patient selection and insufficient evaluation of this technique may explain these circumstances. The aim of our study was to evaluate PCA on general surgery and traumatology wards by means of standardized criteria for technology assessment (i.e. safety, practicability, benefit for patients and medical staff) and the efficacy of pain relief. In a prospective study we investigated 120 patients. In phase I, we performed analgesic therapy with tramadol/metamizol (50 ASA status I-IV patients). In phase II, piritramid had been applied to 70 ASA status I-II patients after an intermediate analysis of phase I. In 7% of the patients technical problems led to an early interruption even at the end of the study period. There were, however, no incidents which caused vital problems for the patients. A mean postoperative pain level of 55 visual analogue scale points (0-100 point scale) was achieved with tramadol/metamizol. PCA was stopped in 16% of the patients due to the occurrence of nausea or vomiting and in two patients due to insufficient pain relief. The use of piritramid in phase II led to lower pain levels and no interruptions of PCA because of ineffectivity or nausea/vomiting.(ABSTRACT TRUNCATED AT 250 WORDS)