ICD implantation with and without combined myocardial revascularisation--incidence of ICD therapy and late survival.

BACKGROUND: Our aim was to evaluate the occurrence of implanted cardioverter-defibrillator (ICD) shock and antitachycardia pacing (ATP), the effect of ICD therapies on mortality and the impact of revascularisation strategies on arrhythmic events. PATIENTS AND METHODS: We investigated 130 CAD patients undergoing ICD implantation between 1984 and 1999. RESULTS: Freedom of shock was 66 +/- 7 %, 48 +/- 9 % and 48 +/- 9 % after 1, 3 and 5 years in patients with revascularisation and 62 +/- 8 %, 43 +/- 8 % and 23 +/- 11 % in patients without revascularisation, respectively; p = n. s. Freedom from ATP was similar in both groups - in patients with revascularisation, 64 +/- 6 %, 58 +/- 7 % and 58 +/- 7 % and without revascularisation 56 +/- 8 %, 51 +/- 9 % and 38 +/- 10 %, respectively; p = n. s. There were no significant differences in cumulative survival between patients with and without revascularisation; p = n. s. CONCLUSIONS: CAD patients with VT/VF and with implanted ICD have, despite successful revascularisation, the same rate of device therapy and mortality as patients without an indication of revascularisation. This implies that patients with chronic ischemic heart disease and ventricular tachyarrhythmias continue to be at risk of sudden death after CABG/PTCA; evaluation for ICD implantation is warranted.

Improving estimates of exposures for epidemiologic studies of plutonium workers.

Epidemiologic studies of nuclear facilities usually focus on relations between cancer and doses from external penetrating radiation, and describe these exposures with little detail on measurement error and missing data. We demonstrate ways to document complex exposures to nuclear workers with data on external and internal exposures to ionizing radiation and toxic chemicals. We describe methods for assessing internal exposures to plutonium and external doses from neutrons; the use of a job exposure matrix for estimating chemical exposures; and methods for imputing missing data for exposures and doses. For plutonium workers at Rocky Flats, errors in estimating neutron doses resulted in underestimating the total external dose for production workers by about 16%. Estimates of systemic deposition do not correlate well with estimates of organ doses. Only a small percentage of workers had exposures to toxic chemicals, making epidemiologic assessments of risk difficult.

Integrating workplace exposure databases for occupational medicine services and epidemiologic studies at a former nuclear weapons facility.

We outline methods for integrating epidemiologic and industrial hygiene data systems for the purpose of exposure estimation, exposure surveillance, worker notification, and occupational medicine practice. We present examples of these methods from our work at the Rocky Flats Plant--a former nuclear weapons facility that fabricated plutonium triggers for nuclear weapons and is now being decontaminated and decommissioned. The weapons production processes exposed workers to plutonium, gamma photons, neutrons, beryllium, asbestos, and several hazardous chemical agents, including chlorinated hydrocarbons and heavy metals. We developed a job exposure matrix (JEM) for estimating exposures to 10 chemical agents in 20 buildings for 120 different job categories over a production history spanning 34 years. With the JEM, we estimated lifetime chemical exposures for about 12,000 of the 16,000 former production workers. We show how the JEM database is used to estimate cumulative exposures over different time periods for epidemiological studies and to provide notification and determine eligibility for a medical screening program developed for former workers. We designed an industrial hygiene data system for maintaining exposure data for current cleanup workers. We describe how this system can be used for exposure surveillance and linked with the JEM and databases on radiation doses to develop lifetime exposure histories and to determine appropriate medical monitoring tests for current cleanup workers. We also present time-line-based graphical methods for reviewing and correcting exposure estimates and reporting them to individual workers.

Alternative to the transvenous approach in pediatric pacing - long-term experiences with bipolar epicardial pacing leads.

BACKGROUND: Cardiovascular anatomy and limited venous access may preclude the implantation of endocardial pacing systems in children as well as adults with congenital heart disease. Thus, the implantation of myo/epicardial pacing leads is required in these patients. The less favorable long-term results experienced in the past with myocardial screw-in leads are often used to justify the transvenous approach whenever possible, even in infants. However, encouraging preliminary results were reported from modern bipolar steroid eluting epicardial pacing leads. Further follow-up data are now warranted to obtain arguments for the dispute regarding the preferable or optimal pacing approach in infants and small children. Methods From January 1994 to November 2000 a total of 64 bipolar steroid-eluting epicardial pacing leads (Medtronic CapSure Epi 10366 and 4968, Medtronic, Inc, Minneapolis, MN, USA) were implanted in 52 children at our institutions (52 electrodes in ventricular and 12 in atrial position). The median age of the children was 25.5 months (range 0.03 to 193 months). As part of a prospective multicenter study these leads were continuously followed in combination with AutoCapture devices since December 1996. Results Telemetry data demonstrated at discharge low pacing thresholds both for the ventricular (0.8±0.37Volt @ 0.5ms) and the atrial leads (0.8±0.4Volt @ 0.5ms) as well as excellent sensing signals (P wave 2.9±1.4mV and R wave 10.6±5.5mV) without significant changes during follow-up up to 24 months. AutoCapture controlled pacing could be applied in 46/52 (88%) children rendering a calculated battery service life of 14.8±2.9 years with a VVIR device (Regency SR 5130, St. Jude Medical, Sylmar, CA, USA) and 10.8±1.1 years with a dual chamber device (Affinity DR 5330, St. Jude Medical, Sylmar, CA, USA). Apart from the necessity to reposition three leads in the immediate postoperative period no late lead related complications have been experienced during follow-up. Conclusions The new steroid-eluting bipolar epicardial pacing lead demonstrates a high reliability and consistent extraordinary pacing as well as sensing thresholds. AutoCapture controlled pacing is feasible in most patients and may result in marked battery service life extension. Hence epicardial pacing can now be highly recommended as the first choice for permanent pacing in infants and children.

Morphology discriminator feature for enhanced ventricular tachycardia discrimination in implantable cardioverter defibrillators.

The morphology discriminator (MD) feature is an electrogram template matching algorithm that intends to improve tachycardia discrimination in implantable cardioverter defibrillators (ICDs). The aim of this study was to evaluate the performance of this feature during spontaneously occurring ventricular and supraventricular tachyarrhythmias and exercise induced sinus tachycardia. Twenty-three patients (20 men, 3 women; mean age 54.3 +/- 13.8 years) with pectorally implanted Ventritex Contour MD, Angstrom MD, and Profile MD ICDs were studied. The stability of the acquired morphology template and performance of the algorithm during spontaneous tachyarrhythmias were evaluated at follow-up. A treadmill exercise test was performed in 16 patients along with continuous telemetric monitoring of matching scores. A satisfactory template could be acquired at baseline in 22 (96%) patients. Variations in electrogram morphology necessitated new template acquisition in seven (30%) patients at first follow-up (6-8 weeks postimplant). During a mean follow-up of 9.1 +/- 3.7 months, 56 ventricular tachycardia (VT) and 15 supraventricular tachycardia episodes (sinus tachycardia in two-thirds) in 11 patients were all appropriately discriminated by the MD feature. Exercise testing showed appropriate discrimination of sinus tachycardia in 15 (94%) of 16 patients. A common observation was postshock changes in electrogram morphology that resulted in transient mismatch with the template. In conclusion, the recently introduced MD feature in ICDs has a high sensitivity for detection of VT and high specificity for rejection of sinus tachycardia. Postshock changes in electrogram morphology have been observed that may cause inappropriate redetection. Marked variations of electrogram morphology over time may be a concern in some patients, especially during lead maturation.

Influence of acute exposure to high altitude and hypoxemia on ventricular stimulation thresholds in pacemaker patients.

Cardiac stimulation threshold of implanted pacemakers may be influenced by a variety of endogenous and exogenous factors. High altitude provokes hypoxemia, which may change stimulation thresholds, besides causing other important physiological changes. The aim of our study was to investigate the influence of high altitude on ventricular stimulation thresholds in pacemaker patients. Thirteen patients (10 men; aged 65.5 +/- 4.8 years) with implanted single chamber pacemakers (nine with Pacesetter Regency SR+ with the Autocapture feature) were exposed to an altitude of 4,000 m above sea level, as simulated in a hypobaric chamber. Stepwise ascension was performed with a speed of 5 m/s starting at 450 m above sea level. A 5-minute rest was performed every 500 m to measure stimulation threshold at each step. After a stay of 30 minutes at 4,000 m stimulation threshold was measured, followed by a stepwise descent. Pacemaker interrogation and arterial blood gas analysis were performed at 450 and at 4,000 m, and a strength-duration curve was determined. Blood pressure, heart rate, and oxygen saturation were monitored continuously during the study. Ascent to 4,000 m above sea level induced a significant decrease in arterial pO2 (10.7 +/- 1.1 vs 5.5 +/- 0.3 kPa), pCO2 (5.3 +/- 0.3 vs 4.7 +/- 0.4 kPa), oxygen saturation measured by arterial blood gas analysis (95.5% +/- 1.2% vs 79.1% +/- 2.5%), and increase in pH (7.39 +/- 0.02 vs 7.45 +/- 0.04) (P < 0.0001). Stimulation thresholds and the strength-duration curve remained unchanged in all patients throughout the study. In conclusion, exposure to an altitude of 4,000 m above sea level with resultant hypobaric hypoxemia has no impact on ventricular stimulation thresholds. Therefore, in regard to the safety of pacing, pacemaker patients can safely be exposed to this altitude.

DDD pacing mode survival in children with a dual-chamber pacemaker.

BACKGROUND: The persistence of DDD pacing is well documented in adults, however, in children survival of the DDD pacing mode is less clear. METHODS: We studied the survival of dual-chamber (DDD) pacing in 36 children aged 1 week to 16 years who underwent implantation of a dual-chamber pacing system between January 1986 and October 1998. The children were divided in the following two groups: 26 had epicardial pacing systems and 10 had endocardial pacing systems. RESULTS: During long-term follow-up 11 patients lost the DDD pacing mode. The DDD pacing survival rate at 3 months and 1, 2, and 5 years was 80%, 77%, 73%, and 69%, respectively. Age, weight, congenital heart disease, and epicardial pacing leads were not found to be risk factors for loss of DDD pacing mode. However, P-wave values of less than 2.5 mV at implantation of epicardial leads were associated with loss of the DDD pacing mode. CONCLUSIONS: The majority of children remain in the DDD pacing mode during long-term follow-up. A P-wave value of less than 2.5 mV at implantation of epicardial leads is a risk factor for loss of the DDD pacing mode.

Low-energy epicardial pacing in children: the benefit of autocapture.

BACKGROUND: Permanent cardiac pacing in children results commonly in augmented energy consumption because of the high pacing rates and the ample stimulation safety margin applied in children. Cardiovascular anatomy and limited venous access sometimes preclude the otherwise preferred endocardial approach. In this multicenter patient series, we studied the feasibility, safety, and energy saving obtained by a combination of steroid-eluting epicardial leads with autocapture devices capable of ongoing adjustment of the stimulation output to the prevailing threshold. METHODS: Autocapture devices (Pacesetter Microny SR+/- and Regency SR+/-; Pacesetter, Solna, Sweden) and steroid-eluting epicardial pacing leads (Medtronic CapSure Epi 10366; Medtronic, Inc, Minneapolis, MN) were implanted in 14 children. Thresholds, telemetry data, evoked response, and polarization signals were obtained at discharge and follow-up, and battery service life was calculated. RESULTS: During a median follow-up of 6.5 months, autocapture pacing was applied in 12 of 14 children. The automatically adjusted pulse amplitude of autocapture devices demonstrated low-energy pacing with no significant changes between discharge and 6 months follow-up (1.1 +/- 0.3 versus 0.9 +/- 0.3 V). Autocapture-programmed pacemakers had calculated life spans of 7.8 +/- 1.4 years (Microny) and 21.0 +/- 1.6 years (Regency). No adverse effects were noted. CONCLUSIONS: Autocapture-controlled pacing with bipolar epicardial pacing leads is feasible and safe in children. Autocapture programming results in substantial energy savings and extends battery life markedly.

The potential for inappropriate ventricular tachycardia confirmation using the Intracardiac Electrogram (EGM) Width Criterion.

The "Intracardiac Electrogram (EGM) Width Criterion," the first digital signal processing feature used in an implantable cardioverter defibrillator (ICD), is a detection enhancement algorithm that intends to improve ventricular tachycardia (VT) detection specificity by rejecting inappropriately detected supraventricular tachyarrhythmias. The algorithm may be activated after setting the optimal EGM source, slew, and width thresholds based on EGM width testing during sinus rhythm. This study evaluates the accuracy of the EGM width measurements during exercise testing. Twenty-one patients with Medtronic Micro Jewel II Model 7223 ICDs underwent treadmill exercise testing. EGM width testing was repeatedly performed during exercise and recovery to detect potential inappropriate measurements. In seven (33%) patients the EGM Width Criterion inappropriately confirmed VT detection. Eleven patients had inappropriately wide EGM width measurements, but did not satisfy the EGM Width Criterion. The causes of wide EGM width measurements were an actual increase in EGM width and/or inappropriate detection of the baseline irregularities as EGM onset or offset points. Based on our observations, we recommend to test the EGM Width Criterion during exercise testing for optimal ICD programming.

Acute hemodynamic effects of alternate and combined site pacing in patients after cardiac surgery.

We hypothesized that pacing at sites other than the right ventricular (RV) apex or at two or more ventricular sites would activate the myocardium more rapidly and improve cardiac function in patients undergoing coronary revascularization or aortic valve replacement. Epicardial electrodes were placed on the right atrium (A), RV paraseptal area close to the RV apex (B), RV outflow tract (C), LV apex (D), in patients undergoing bypass surgery. At constant rate and AV delay, we measured CO during A pacing, DVI pacing at B, C, D, and various combinations of sites in random order in ten patients with EF > 50% and 27 patients with EF < or = 50%. When pacing at two sites, we made one electrode a cathode and one an anode and noted two distinct thresholds by careful observation of the 12-lead ECG. There were no significant differences in CO, systemic vascular resistance, systolic, or mean arterial pressure. Significant differences were noted in QRS duration, which increased progressively going from AAI to 3-site, 2-site, and single site pacing (P < 0.05 each comparison). Thus: (1) QRS duration correlated inversely with the number of ventricular sites paced; (2) despite this, CO did not improve irrespective of baseline EF; (3) multisite pacing produced multiple distinct thresholds which appeared to be related to the number of sites paced, and (4) unique ECG patterns confirmed multisite pacing.

Long-term follow-up in hypertrophic obstructive cardiomyopathy after septal myectomy.

BACKGROUND: Controversy exists about the choice of treatment for patients with hypertrophic obstructive cardiomyopathy. The purpose of this study was to evaluate clinical and echocardiographic long-term results in patients with hypertrophic obstructive cardiomyopathy after septal myectomy and to determine predictors of event-free survival in these patients. METHODS: Between 1965 and 1995, 110 consecutive patients 2 to 66 years old (mean age, 37 +/- 15 years) with an invasively measured left ventricular outflow tract gradient of 86 +/- 39 mm Hg (81 +/- 42 mm Hg by Doppler echocardiography) underwent either septal myectomy only (n = 87) or myectomy combined with additional procedures (n = 23). Mean follow-up was 11.7 +/- 7.5 years. Predictors of late events were calculated using multivariate Cox regression analysis. RESULTS: The perioperative mortality rate was 3.6% (n = 4). The cumulative survival rate at 5, 10, and 15 years was 93%, 80%, and 72%, respectively, and symptom-free survival, 77%, 50%, and 33%, respectively. Predictors of late death were New York Heart Association class III or IV (p < 0.05), congestive heart failure (p < 0.05) and additional procedures (p < 0.05). The left ventricular outflow tract gradient was nearly eliminated in all patients, the left atrial dimension decreased significantly during the early years, and left ventricular dilatation occurred late in 17 patients. CONCLUSIONS: Septal myectomy is associated with a low perioperative mortality and a high late survival rate (72% at 15 years' follow-up). Septal myectomy is still an excellent modality in the treatment strategy for symptomatic patients with hypertrophic obstructive cardiomyopathy.

Temporary loss of cardiac autonomic innervation after the maze procedure.

OBJECTIVE: Blunted sinus node response to exercise has been reported after the maze operation. We suggested the autonomic vegetative function of the heart to be disturbed after the maze procedure. METHODS: 17 patients, mean age 63 +/- 15 years, with chronic atrial fibrillation for 49 +/- 46 months (range 5-65) underwent the maze procedure during mitral valve surgery. Bicycle stress test, 24-h electrocardiography and heart rate variability were analysed in 11 patients after three and in six after 14 +/- 3 months. Spectral analysis within two frequency bands, vector analysis of the main circular resultant and influence of orthostasis and Valsalva manoeuvre on different R-R intervals were calculated. RESULTS: One patient died from a perioperative ischaemic stroke. At follow-up, all patients were in sinus rhythm. Heart rate reached 84 +/- 14%, the mean circular resultant was 60 +/- 48%, the ratio of the longest to the shortest R-R interval during the Valsalva manoeuvre was 92 +/- 8% and the ratio of maximal to minimal R-R interval after orthostasis was 98 +/- 4% of the age-adjusted normal value. Maximal workload was 116 +/- 31 watts. All patients had abnormal heart rate variability. Heart rate variability was significantly more blunted after three months, than after 14 months (P < 0.05). The minimal heart rate and the difference between the maximal and the minimal heart rate during the 24-h electrocardiography were significantly correlated to the number of normal physiological tests (r = -0.52; P < 0.05; r = 0.71; P < 0.005); for the maximal heart rate, there was a positive trend only (r = 0.44; P = 0.07). CONCLUSIONS: Early after the maze procedure, a nearly total denervation of the sinus node is present, similar as seen after heart transplantation, with partial restoration of the autonomic function after one year. The exercise capacity of the patients was satisfactory.

[Severe aortic valve diseases and aortic isthmus stenosis in adults. Incidence, clinical aspects and long-term results of surgical treatment]. / Schwere Aortenvitien und Aortenisthmusstenose bei Erwachsenen. Häufigkeit, Klinik und Langzeitergebnisse der chirurgischen Behandlung.

Severe aortic valve disease is a rare complication of coarctation in adults. Between 1961 and 1990 aortic valve replacement was performed after or combined with the operation of coarctation in 24 adults (4% of entire population operated for coarctation). Bicuspid aortic valves were present in 2/3 of patients. In 10 patients (7/10 with aortic stenosis) coarctation was operated early (mean age 24 years) and aortic valve late (mean age 40 years): in 14 (10/14 with aortic regurgitation, mean age 40 years) aortic valve and coarctation were operated simultaneously (8 patients) or staged within 6 months (6 patients). Additional surgical interventions on the dilated aorta ascendens were performed in 8, mitral valve replacement in 2 and aorto-coronary bypass in 1 patients. Early mortality was 2/24 (8%) and was similar in simultaneously (1/8) and staged (1/14) operated cases: 10 year survival was lower than in an age-matched group of 72 patients with aortic valve disease of similar severity operated during the same period (70% vs 88%, p < 0.01): 6/7 late deaths were cardiac; 5/5 pts with preoperatively severely increased end-diastolic (> 199 ml/m2) and 4/4 with end-systolic (> 90 ml/m2) left ventricular volumes and 2/2 with ejection fraction < 41% died late postoperatively. Severe aortic valve disease arised in 4% of adults with coarctation or after coarctation resection. The results of valve replacement in these patients were less successful due to high late mortality in cases with severe preoperative left ventricular dilatation and/or decrease of ejection fraction. Thus, close surveillance of patients after coarctation surgery, especially those with bicuspid valves, is mandatory for early detection of valvular disease and appropriate timing of valve replacement before left ventricular function begins to deteriorate.

Aortic valve preservation in acute type A dissection: is it sound?

A series of 200 consecutive patients with acute Stanford type A dissection (157 men, 78%; 43 women, 22%) was analyzed to assess the validity of aortic valve preservation or repair. Indication for the operation in most cases was based on echocardiographic examination alone, to reduce the delay. In the majority of patients (111/200, 56%) the aortic valve was preserved or repaired if necessary. Aortic root replacement with a composite graft was performed in 66 of 200 patients (33%), mainly because of an enlarged aortic anulus and sinus. Replacement of the aortic valve and the supracoronary ascending aorta was performed in 23 of 200 patients (12%) with a diseased aortic valve (e.g., bicuspid valve) but an acceptable aortic sinus. Follow-up totaled 656 patient-years (maximum 14 years). Actuarial analyses as a function of type of repair and type of aortic valve provided the following probabilities plus or minus errors (95%): overall survival of the 200 patients was 78.3% +/- 2.9% after 30 days, 74.95% +/- 3.1% after 1 year, 67.9% +/- 3.6% after 5 years, and 48.5% +/- 6.1% after 10 years. Actuarial probability of freedom from reoperation for valve failure in the complete series was calculated as 100.0% +/- 0.0% after 30 days, 99.3% +/- 0.7% after 1 year, 97.5% +/- 1.5% after 5 years, and 95.1% +/- 2.8% after 10 years. During long-term follow-up, there was no significant difference among groups with regard to structural deterioration, valve thrombosis, thromboembolic complications, anticoagulant-induced hemorrhage, and endocarditis. Freedom from valve failure and valve-related complications are similar for preserved, repaired, mechanical, and biologic valves. Valve-related reoperations are rare during at least 5 years of follow-up. Hence preservation or repair of the aortic valve can be recommended in the majority of patients with acute type A dissection.

Surgery for ruptured thoracic and thoraco-abdominal aortic aneurysms.

OBJECTIVE: To assess the outcome of patients with ruptured descending thoracic and thoracoabdominal aortic aneurysms undergoing emergency repair, in comparison to elective surgery for chronic lesions. METHODS: A prospective study of 100 consecutive patients operated upon the descending aorta (1-8 segments) using proximal unloading and distal protection with partial cardiopulmonary bypass, heparin surface-coated perfusion equipment and low systemic heparinization (loading dose 100 IU/kg, activated coagulation time > 180 s), staged cross-clamping, sealed grafts and graft inclusion. RESULTS: Arteriosclerotic lesions were present in 53/100 patients (53%) for all, 30/53 (56%) for chronic, and 21/33 (63%) for ruptured, aneurysms (NS). Dissecting lesions were found in 38/100 patients (38%) for all, 20/53 (38%) for chronic, and 8/33 (24%) for ruptured aneurysms (NS). Preoperative hematocrit was 38 +/- 6% for all, 40 +/- 5% for chronic, and 33 +/- 5% for ruptured aneurysmal patients (P < 0.001 ruptured versus chronic). The extent of aortic repair (1-8 segments) was 3.3 +/- 1.6 for all, 3.5 +/- 1.5 for chronic, and 3.2 +/- 1.4 for ruptured, aneurysms (NS). Transdiaphragmatic repair was performed in 51/100 (51%) of all, 28/53 (53%) of chronic, and 17/33 (51%) of ruptured aneurysms (NS). Aortic cross-clamp time was 38 +/- 21 min for all, 39 +/- 24 min for chronic, and 38 +/- 17 min for ruptured, aneurysmal patients (NS). The amount of red cells washed and autotransfused was 2792 +/- 2239 ml in all, 3143 +/- 2531 ml in chronic, and 2074 +/- 1350 ml in ruptured, aneurysmal patients (P < 0.025). The amount of packed red cells required was 2181 +/- 1830 ml for all, 1736 +/- 1333 ml for chronic, and 2947 +/- 2395 ml for ruptured aneurysmal patients (P < 0.010). Thirty-day mortality was 9/100 (9%) for all, 3/53 (6%) for chronic, and 5/33 (15%) for ruptured aneurysmal patients (NS). Parapareses/plegias occurred in 9/100 (9%) of all, 6/53 (11%) of chronic, and 3/33 (9%) of ruptured, aneurysmal patients (NS). Stepwise regression analysis identified aortic cross-clamp time as a predictor of early mortality (P = 0.002) and parapareses and paraplegias (P = 0.001). Age (P = 0.001), extent of repair (P = 0.008) and preoperative hematocrit (P = 0.001) were predictors for homologous transfusion requirements. CONCLUSION: Emergency repair of ruptured descending thoracic and thoracoabdominal aortic aneurysms can be achieved with acceptable results.

[Surgical therapy in unstable angina pectoris]. / Chirurgische Therapie bei instabiler Angina pectoris.

In order to assess the value of surgical revascularization of coronary arteries in patients with unstable angina pectoris, a series of 551/3397 consecutive patients belonging to New York Heart Association (NYHA) class IV was investigated. Fulfillment of at least two of the following criteria is mandatory for diagnosis unstable angina pectoris: slightly increased CK (< 300 IU/l), modified ECG at rest (decreased ST-T, increased ST), therapy-resistant post-infarction angina, therapy-resistant angina at rest, increased severity, duration or frequency of angina attacks within the last three months, insufficient therapeutic response. Patients with acute myocardial infarction were excluded from analysis. 362/551 patients out of the investigated cohort fulfilled criteria of unstable angina pectoris NYHA class IV; in 189/551 patients, criteria of stable angina pectoris NYHA class IV were fulfilled (controls). The mean follow-up period for these patients was 72 +/- 33 months (24 +/- 144 months). There were no differences regarding age, percentage of patients with three vessel disease, ejection fraction of the left ventricle and of cardiogenic shock. The mean number of aortocoronary grafts was 3.8 +/- 1.3 in patients with unstable angina, compared to 3.4 +/- 1.5 in patients with stable angina pectoris (p < 0.05). An intra-aortic balloon pump had to be applied in 8% of patients with unstable angina compared to 3% in stable angina. A mortality of 2% within 30 days of surgery was registered in unstable compared to 3% in stable angina pectoris (n.s).(ABSTRACT TRUNCATED AT 250 WORDS)

[Occlusion of the distal aorta]. / Verschluss der distalen Aorta.

Between 1984 and 1992, 79 patients were operated for occlusion of the infrarenal abdominal aorta. 12/79 (15%) of the patients underwent emergency procedure for an acute Leriche syndrome. 67/79 (85%) of the patients with a chronic occlusion were treated electively. The surgical management includes in our series in 57/79 (72%) cases aortoiliac or aortofemoral prosthetic bypass, in 11/79 (14%) cases aortoiliac endarterectomy, in 6/79 (8%) cases embolectomy and in 5/79 (6%) extraanatomical axillofemoral bypass. For chronic total occlusion of the aorta the most common procedure was prosthetic bypass in anatomical position. For emergency cases embolectomy was performed in 42%. Early morbidity rate was 26% (21/79). The most frequent complications were thromboembolic events in 7 patients, myocardial infarction in 4 patients and renal insufficiency in 4 cases. The 30-day mortality 2.5% (2/79); the cause in both cases myocardial infarction. For atherosclerotic occlusive disease of the infrarenal abdominal aorta the prosthetic bypass is the first-choice surgical procedure. For embolic occlusions and for risk patients other less burdening procedures are available.

[Cardiovascular interventions in elderly patients]. / Kardiovaskuläre Eingriffe bei älteren Patienten.

From January 1981 to December 1990, 204 patients between 70 and 81 years of age underwent aortocoronary bypass-surgery, and 20 patients age 80 years or older underwent valvular surgery. The operative mortality rate (30-day mortality) of aortocoronary bypass-surgery was 6.8%; actuarial survival rate at 1 and 5 years was 92% and 86%, respectively. The operative mortality rate of valvular surgery was 15%; actuarial survival rate at 1 and 5 years was 78.5% and 67%, respectively. The mean follow-up was 25 months. Most patients undergoing myocardial revascularization (71%) and all the patients undergoing valvular surgery were preoperatively in New York Heart Association (NYHA) functional class III or IV, at the end of the follow-up in NYHA functional class I or II (95%). A rapid rise in the number of heart operations in the elderly is evident. It is associated with increased but acceptable operative risk. Longterm results and postoperative improvement of functional status are satisfactory.

[Surgery of endocarditis in the drug dependent and HIV patient. A prospective comparison with conservative treatment]. / Chirurgie der Endokarditis beim Drogensüchtigen und HIV-Patient. Ein prospektiver Vergleich mit der konservativen Behandlung.

The incidence of infective endocarditis in drug addicts is increasing with the spreading of intravenous drug abuse. The tricuspid valve is the most commonly involved valve followed by the mitral valve. We evaluated prospectively 22 patients with a mean age of 23 years, presenting with addiction-associated endocarditis endocarditis and referred to our institution during a three-year period. The tricuspid valve was involved in 13 instances, mitral valve in 4, mitral plus tricuspid valve in 5 patients and aortic valve in 1 case. Staphylococcus aureus was the most frequent infective organism (15x), followed by Streptococci (4x), Corynebacteria (2x) and one case with a mixed infection. Six patients were positive for an HIV-infection and 17 had evidence for a chronic viral hepatitis. Ten patients (3 of them HIV-seropositive) were treated surgically. Resection of the tricuspid valve with (1x) or without replacement (4x), resection of vegetations and valve repair (2x), mitral valve replacement (2x), aortic valve replacement (1x) were performed. In case of tricuspid endocarditis, the decision whether to proceed with resection, repair or replacement with a bioprosthesis was taken according to valve pathology and the psycho-social situation of the patient. When the vegetations involved only one leaflet and could be removed easily, vegetectomy with annuloplasty or with repair using autologous pericardium was performed. Valvulectomy without replacement was the chosen method for those where persistent or recurrent drug abuse could not be excluded. A bioprosthesis was inserted when the tricuspid valve was completely destroyed and there was a proven abstinence from drugs over a period of several weeks preoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)