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Complete atrioventricular block occurred during spinal and subsequent general anaesthesia in a 74-year-old patient with known arterial hypertension but without heart conduction abnormality. Drug therapy and intermittent transcutaneous pacing was successful. A decrease of arterial pressure by more than 40% preceded the heart blockade in the course of both events. Subsequent cardiologic examination revealed evidence of a discrete hypertensive heart disease. Relative ischemia of the atrioventricular region during anaesthesia was suggested as an aetiology. When the patient presented for the next operation, again general anaesthesia was applied, and invasive arterial blood pressure monitoring as well as catecholamine support were used and no further atrioventricular blockade occurred. The case demonstrates the possible recurrence of an intraoperative complete atrioventricular blockade in an older patient without pre-existing conduction abnormalities and only minor signs of heart disease, irrespective of the anaesthesia technique. Under these circumstances transcutaneous pacing should always be in place. Maintenance of coronary perfusion pressure is essential and invasive blood pressure monitoring is recommended.

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AIMS: The aim of this study was to assess quality of life (QoL) and exercise capacity during permanent ventricular stimulation (PVS) compared with intrinsic atrioventricular conduction (IAVC) in patients with dual chamber pacemakers (PMs) and an intrinsic PQ interval >210 ms. Dual chamber PMs in patients with atrioventricular (AV) block are usually programmed to PVS in VDD or DDD mode, although IAVC is preserved, but prolonged. This results in PVS, although long periods of IAVC may occur. METHODS AND RESULTS: Fourteen consecutive patients (age 76 +/- 6 years; intermittent high degree AV block in six patients, binodal disease in eight patients) were enroled in a prospective, randomized, single blind, crossover study of IAVC vs PVC. To permit IAVC, programmed AV delays were prolonged. At the end of each phase, QoL scores were assessed using a questionnaire and echocardiography and cardiopulmonary stress tests were performed. During the study period with IAVC, 95 +/- 10% of the beats were conducted intrinsically. QoL scores (28.3 +/- 11 vs 29.3 +/- 13; P = 0.68), peak exercise capacity (5.4 +/- 2.4 vs 5.2 +/- 2.9 METs; P = 0.35) and peak oxygen uptake (19.8 +/- 4.5 vs 18.8 +/- 5.2 ml/kg/min; P = 0.16) were comparable during IAVC and PVS, respectively. Similar echocardiographic values were found for left ventricular (LV) ejection fraction (50 +/- 9% vs 51 +/- 10%; P = 0.67) and velocity time integral at the left ventricular outflow tract (24 +/- 5 vs 22 +/- 6 cm; P = 0.20), respectively. CONCLUSIONS: We conclude that in patients with dual chamber PMs and intermittent high degree AV block neither PVS nor IAVC is superior with respect to QoL or exercise capacity. Therefore, pulse generators may be programmed to IAVC to extend their longevity.

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Until recently a general consensus existed for the clinical entity diagnosed as myocardial infarction using the world health organisation (WHO) definition. According to the WHO definition myocardial infarction was defined by a combination of two of three typical characteristics: typical symptoms, rise of cardiac enzymes (CK, CK-MB), and a typical ECG pattern involving the development of Q waves. New insights into the development of acute myocardial infarction, the superiority of the biochemical characteristics of cardiac troponin assays over CK and CK-MB measurements in blood, and new therapeutic concepts made a new definition of myocardial infarction, e.g. of the acute myocardial infarction, necessary. Timing of the diagnosis of myocardial necrosis is of outmost importance relative to the time of observation (acute, evolving, healing, healed MI), as is the classification of the extent of myocardial damage (microscopic, small, medium or large). The term "acute coronary syndrome" (ACS) has been established as a working diagnosis for choosing the appropriate therapeutic strategy. In patients with ACS and ST elevation ischemia (STEMI ACS, true posterior ischemia inclusive) as well as in patients with presumably new LBBB, immediate reperfusion therapy should be performed (primary PTCA or thrombolytic therapy), whereas in patients with ECG changes other than ST elevation or new LBBB (NSTEMIACS) additional antiplatlet therapy on top of aspirin and heparin is indicated. In contrast to the acute phase of infarction when troponin in blood often is not detectable yet, the diagnosis of definitive myocardial infarction is based primarily on troponin elevation. Hard criteria for established infarction are the development of pathologic Q waves or healing or healed myocardial necrosis in pathology; troponin may be normal then, depending of time relapsed.

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A patient with acute coronary syndrome scheduled for urgent coronary artery bypass grafting developed a profound thrombocytopenia during therapy with intravenous heparin and the glycoprotein IIb/IIIa inhibitor tirofiban. Heparin-induced thrombocytopenia and all other possible aetiologies were unlikely and the low platelet count had to be attributed to tirofiban. Anticoagulation during cardiopulmonary bypass was successfully managed with standard heparin. Implications for the diagnosis of coagulation disorders and the management of perioperative anticoagulation are discussed.

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A large coronary aneurysm, originating from a side branch of the right coronary artery, caused recurrent ischemia resulting in myocardial infarction. Successful surgical excision, without concomitant coronary artery bypass grafting, is described.

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BACKGROUND: Randomised trials have shown that primary percutaneous angioplasty (PTCA) may offer advantages over thrombolysis in treating acute myocardial infarction (vessel patency is achieved more often, mortality and reinfarction rate are lower, cerebrovascular accidents are less frequent). Data from several foreign registries have been less clear. Up to now no registry data have been available for Switzerland. Data from registries are very important in planning optimal treatment under "real world" conditions. METHOD: All patients receiving acute PTCA during the first 24 hours of acute myocardial infarction were prospectively included in a registry at a single centre. We assessed times until revascularisation, as well as clinical, angiographic and outcome data. RESULTS: 503 patients (age 59 +/- 12 years, 15% women) were included from 1. 1. 1995 to 30.6.2000. Primary PTCA was performed in 334 patients, and rescue PTCA in 169. Diabetes mellitus was present in 36% of the total. Multivessel disease was present in 61%, anterior infarction in 36%, and 16% were in cardiogenic shock before intervention. The pre-hospital delay was 2:12 h (median). In-hospital decision delay (hospital admission until contact to cardiologist) in patients with primary PTCA was 31 minutes (median). The time from vessel puncture to recanalisation was 19 minutes (median). 273 patients were transferred for coronary angiography and intervention by other hospitals (218 by ground ambulance, 55 per helicopter transfer). The total transfer time (calculated from time of decision to arrival in the catheterization laboratory) was 57 minutes (median). PTCA was successful angiographically in 97% and TIMI 3 flow was obtained in 93% of all patients. Hospital mortality was low in view of the high proportion of patients in cardiogenic shock prior to PTCA (mortality in shock patients was 33%). Mortality in patients without pre-existing cardiogenic shock was 2%. CONCLUSION: Patients with acute myocardial infarction, especially high-risk patients, can be treated successfully by acute PTCA around the clock in Switzerland, in accordance with the strict international recommendations for time delays. The treatment results are similar to those in randomised trials. Transfer of patients from referral hospital is safe, with acceptable delays. Optimisation of the decision process and transport logistics may further improve outcome by reducing the total ischaemia time.

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OBJECTIVE: To investigate the feasibility, safety, and associated time delays of interhospital transfer in patients with acute myocardial infarction for primary percutaneous transluminal coronary angioplasty (PTCA). DESIGN AND PATIENTS: Prospective observational study with group comparison in a single centre. 68 consecutive patients with acute myocardial infarction transferred for primary PTCA from other hospitals (group A) were compared with 78 patients admitted directly to the referral centre (group B). MAIN OUTCOME MEASURES: Patient groups were analysed with regard to baseline characteristics, time intervals from onset of chest pain to balloon angioplasty, hospital stay, and follow up outcome. RESULTS: Patients in group A presented with a higher rate of cardiogenic shock initially than patients in group B (25% v 6%, p = 0.01) and had been resuscitated more frequently before PTCA (22% v 5%, p = 0.01). No deaths or other serious complications occurred during interhospital transfer. Median transfer time was 63 (range 40-115) minutes for helicopter transport (median 42 (28-122) km, n = 14), and 50 (18-110) minutes by ground ambulance (median 8 (5-68) km, n = 54). The median time interval from the decision to perform coronary arteriography to balloon inflation was 96 (45-243) minutes in group A and 52 (17-214) minutes in group B (p = 0.0001). In transferred patients (group A) the transportation associated delay and the longer in-hospital median decision time (50 (10-1120) minutes in group A v 15 (0-210) minutes in group B, p = 0.002) concurred with a longer total period of ischaemia (239 (114-1307) minutes in group A v 182 (75-1025) minutes in group B, p = 0.02) since the beginning of chest pain. Success of PTCA (TIMI 3 flow in 95% of all patients), in-hospital mortality (7% v 9%, mortality for patients not in cardiogenic shock 0% v 4%), and follow up after median 235 days was similarly favourable in groups A and B, respectively. Only one hospital survivor (group A) died during follow up. CONCLUSION: Interhospital transport for primary PTCA in high risk patients with acute myocardial infarction is safe and feasible within a reasonable period of time. Short and medium term outcome is favourable. Optimising the decision process and transport logistics may further improve outcome by reducing the total time of ischaemia.

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The successful application of single-lead VDD pacing during the last few years has generated the idea of single-lead DDD pacing. Preliminary data from several single-lead VDD studies attempting to pace the atrium by a floating atrial dipole are unsatisfactory, causing an unacceptably high current drain of the device. We studied the feasibility as well as the short- and long-term stability of atrioventricular sequential pacing, using a new single-pass, tined DDD lead. In eight consecutive patients (age 73+/-16 years) with symptomatic higher degree AV block and intact sinus node function, this new single-pass DDD lead was implanted in combination with a DDDR pacemaker. Correct VDD and DDD function was studied at implantation; at discharge; and at 1, 3, and 6 months of follow-up. At implant, the atrial stimulation threshold was 0.6+/-0.1 V/0.5 ms. During follow-up, the atrial pacing thresholds in different every day positions averaged 2.1+/-0.5 V at discharge, 2.9+/-0.5 V at 1 month, 3.8+/-0.4 V at 3 months, and 3.4+/-0.4 V at 6 months (pulse width always 0.5 ms). The measured P wave amplitude at implantation was 4.5+/-2.2 mV; during follow-up the telemetered atrial sensitivity thresholds averaged 2.1+/-0.3 mV. Phrenic nerve stimulation at high output pacing (5.0 V/0.5 ms) was observed in three (38%) patients at discharge and in one (13%) patient during follow-up; an intermittent unmeasurable atrial lead impedance at 3 and 6 months follow-up was documented in one (13%) patient. This study confirms the possibility of short- and long-term DDD pacing using a single-pass DDD lead. Since atrial stimulation thresholds are still relatively high compared to conventional dual-lead DDD pacing, further improvements of the atrial electrodes are desirable, enabling lower pacing thresholds and optimizing energy requirements as well as minimizing the potential disadvantage of phrenic nerve stimulation.

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BACKGROUND: Patients with end-stage renal disease on regular hemodialysis have an increased prevalence of left ventricular (LV) hypertrophy that is associated with morbidity and mortality. Asymmetric septal hypertrophy and impairment of LV outflow can occur in these patients and may contribute to adverse outcomes. More insight into the prevalence, extent, geometry, and promoting factors of LV hypertrophy is important. METHODS: An unselected group of 62 patients (31 women), aged 55 +/- 14 years, on maintenance hemodialysis was investigated by Doppler echocardiography. Eight patients with valvular heart disease were excluded from further analysis. We assessed prevalence of LV hypertrophy and asymmetric septal hypertrophy, as well as parameters of LV geometry and LV filling and outflow dynamics. RESULTS: Prevalence of LV hypertrophy was 65%. Patients were analyzed according to LV mass and geometry. Mean LV mass index was normal (105 +/- 17 g/m2) in Group 1 without LV hypertrophy (n = 19); it was markedly elevated in Group 2 (symmetric hypertrophy, n = 22) and Group 3 (asymmetric hypertrophy with systolic anterior movement of mitral valve, n = 7), and highest (191 +/- 54 g/m2) in Group 4 (asymmetric hypertrophy without systolic anterior movement of mitral valve, n = 6, p < 0.001). Age, body mass index, and duration of hypertension were associated with LV hypertrophy and asymmetric septal hypertrophy (p = 0.01). Group 3 with systolic anterior motion of mitral valve had the smallest end-diastolic LV diameters (p = 0.02); increased heart rates, and increased ejection velocities in the LV outflow tract (p = 0.03, and p = 0.005, respectively, vs. Groups 1, 2, and 4) which pointed to an impairment of LV outflow. CONCLUSIONS: Symmetric LV hypertrophy and asymmetric septal hypertrophy are frequent in patients on maintenance hemodialysis. Predictors for LV hypertrophy were age and body mass index, and, particularly for asymmetric septal hypertrophy, age and hypertension duration. Volume withdrawal during hemodialysis may lead to symptomatic hypotension due to dynamic obstruction in some patients with severe asymmetric septal hypertrophy.

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Cardiogenic shock (CS), defined as forward failure combined with systolic blood pressure < 90 mm Hg and reduced organ perfusion despite adequate volume loading, still has a grim prognosis with mortality rates of 80-100% if the causes are left untreated. The most frequent conditions underlying CS are acute myocardial infarction, acute and severe aortic or mitral incompetence, rapidly progressive dilatative cardiomyopathy and hypertrophic obstructive cardiomyopathy. Whereas correct conservative management by drugs and pacing may be life saving in the latter, the other conditions require early invasive management. Indications for cardiac surgery and circulatory assistance are given for mechanical complications leading to CS. In CS complicating myocardial infarction, comprehensive management with early invasive revascularization and intraaortic balloon pumping may result in improved survival compared with the disappointing outcome of medical treatment, including fibrinolysis. This strategy can be offered to the majority of infarct patients in CS, who are primarily admitted to hospitals not equipped for interventional cardiology or cardiac surgery. Between-hospital transfer of these patients for PTCA (or surgery) and advanced intensive care has been shown to be feasible and safe.

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We report on a patient with a giant aneurysm arising from the right coronary artery leading to infarction due to a steal phenomenon. Emergency coronary angiography was performed. The orifice of the aneurysm was occluded by balloon catheter restoring blood flow and resolving ischemia. Aneurysmectomie was done subsequently. The patient recovered very soon, and the following course was uneventful. This case illustrates that occasionally causes other than usual coronary atherosclerosis may lead to acute coronary syndromes.

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Short- and long-term results for DDD pacing using a single-pass DDD lead are presented for 3 patients. Single-lead DDD pacing is feasible and may provide major advantages by eliminating the necessity of a second lead.

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The case of a 45-year-old woman with pheochromocytoma, who presented with severe abdominal pain and headache, diabetes mellitus, lactic acidosis and pulmonary edema, is described and discussed. Spleen infarction, not so far described as an ischemic complication of pheochromocytoma, was seen in computer tomography. After medical pretreatment with labetalol, a pheochromocytoma (2 x 2 cm) of the left adrenal gland was removed. The postoperative course was uneventful.

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We report on a boy with mosaic trisomy 15. The clinical manifestations are compared with those of the few cases reported up to now. A clinical syndrome is delineated consisting of a characteristic shape of the nose and other minor craniofacial anomalies, as well as typical deformities of the hands and feet. Different degrees of mosaicism may explain the more or less severe manifestations in individual patients.

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OBJECTIVE: To assess the risk of aortic valve replacement and long-term follow-up in elderly patients with dominant aortic stenosis. DESIGN: Retrospective analysis of patients who had aortic valve replacement over a 10 year period and were routinely seen in an outpatient clinic. SETTING: University hospital. PATIENTS: 93 patients aged > or = 60 and 47 patients > or = 70 years with symptomatic aortic stenosis undergoing aortic valve replacement. MAIN OUTCOME MEASURES: Early and late mortality in different age groups. Influence of preoperative signs and symptoms on overall outcome. RESULTS: The proportion of patients older than 70 years increased from 11% in 1978 to 54% in 1986. Perioperative mortality was 3.6% and mortality after 2 and 5 years was 9% and 13% respectively. Survival was similar (85% and 83%, respectively) in patients aged 60-69 years (group 1, n = 93, mean age 64.5 (2.7) and patients aged > or = 70 years (group 2, n = 47, mean age 72.6 (2.5)). Additional coronary artery disease and coronary bypass grafting did not significantly affect survival. The cardiothoracic ratio was inversely related to survival (Cox regression, p < 0.05). Preoperative symptoms (syncope, angina pectoris, and dyspnoea) were similar in both patient groups. After a mean (SD) follow up of 51 (33) months 96% of surviving patients were in NYHA functional class I or II with no difference between the two age groups. Similarly, the cardiothoracic ratio and Sokolow index decreased to near normal values in both age groups. CONCLUSION: The risk of aortic valve replacement in patients with dominant aortic stenosis is low and not significantly influenced by age. Therefore replacement may be performed without increased risk in elderly patients and with a good long-term outcome.

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OBJECTIVE: To identify valvar heart disease in patients with chronic uraemia by conventional and colour coded Doppler echocardiography. DESIGN: Case series of an unselected group of 62 patients with end stage renal failure. SETTING: Centre for haemodialysis in a referral hospital in Switzerland. PATIENTS: 62 patients on chronic haemodialysis. MAIN OUTCOME MEASURES: Frequency of structural and functional valve abnormalities and their relation to clinical findings. RESULTS: Structural changes were seen in 40 (64%) of 62 patients after 50 months (range 3-178 months) on haemodialysis. The mitral annulus and aortic cusps were thickened in 25 (40%) and in 34 (55%) patients respectively. Aortic stenosis was present in eight (mean (SD) age 60.5 (8.5) years), with a maximal instantaneous pressure gradient of 41 (14) mm Hg. Aortic regurgitation was seen in eight, mitral regurgitation in seven, and mitral stenosis in three patients. Patients with aortic stenosis had been on haemodialysis for significantly longer than the remaining patients (101 (43) v 46 (43) months, p = 0.01) and had significantly higher concentrations of serum alkaline phosphatase (176 (89) v 117 (47) IU/l, p less than 0.01) and of parathyroid hormone (54 (66) v 19 (29) ng/ml, p less than 0.02). CONCLUSIONS: Patients on long-term haemodialysis had an increased frequency of haemodynamically relevant changes in the aortic and mitral valves. The degenerative valve disease may be related in part to the duration of haemodialysis and to alterations in calcium metabolism as indicated by increased plasma concentrations of alkaline phosphatase and parathyroid hormone.

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The effects of acute pH changes on whole body leucine kinetics (1-13C-leucine infusion technique) were determined in normal subjects. Plasma insulin, glucagon, and growth hormone concentrations were kept constant by somatostatin and replacement infusions of the three hormones. When acidosis was produced by ingestion of NH4Cl (4 mmol kg-1 p.os; n = 8) arterialized pH decreased within 3 h from 7.39 +/- 0.01 to 7.31 +/- 0.01 (P less than 0.001) and leucine plasma appearance increased by 0.13 +/- 0.04 mumol kg-1 min-1 (P less than 0.02); in contrast, when alkalosis was produced by intravenous infusion of 4 mmol kg-1 NaHCO3 (n = 7, pH 7.47 +/- 0.01), leucine plasma appearance decreased by -0.09 +/- 0.04 mumol kg-1 min-1 (P less than 0.01 vs. acidosis). Whole body leucine flux also increased during acidosis compared to alkalosis (P less than 0.05), suggesting an increase in whole body protein breakdown during acidosis. Apparent leucine oxidation increased during acidosis compared to alkalosis (P = 0.05). Net forearm leucine exchange remained unaffected by acute pH changes. Plasma FFA concentrations decreased during acidosis by -107 +/- 67 mumol l-1 (P less than 0.05) and plasma glucose increased by 1.90 +/- 0.25 mmol l-1 (P less than 0.02); in contrast, alkalosis resulted in an increase in plasma FFA by 83 +/- 40 mumol l-1 (P less than 0.02; P less than 0.01 vs. acidosis), suggesting an increase in lipolysis; plasma glucose decreased compared to acidosis (P less than 0.01). The data demonstrate that acute metabolic acidosis and alkalosis, as they occur in clinical conditions, influence protein breakdown, and in the opposite direction, lipolysis.

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The course of left ventricular hypertrophy was investigated in anemic hemodialysis patients treated with recombinant human erythropoietin (r-huEPO). 12 patients, aged 60.8 +/- 9.9 years (mean +/- SD) were treated for 18.8 +/- 2.7 months. Left ventricular size was estimated by echocardiography performed before treatment and at least 12 months after relieving anemia. Patients had signs of left ventricular and/or asymmetric septal hypertrophy when compared with a nonanemic and normotensive control group matched for sex and age. At baseline, hemoglobin (Hb) was 8.6 +/- 0.7 g/dl; interventricular septum thickness (IVST) was 1.75 +/- 0.34 cm, left ventricular posterior wall thickness (LVPWT) 1.32 +/- 0.19 cm, left ventricular muscle mass index (LVMI) 222.7 +/- 41 g/m2 and blood pressure (BP) 146.4 +/- 10/81.6 +/- 6 mm Hg. Hb rose to 11.4 +/- 1.2 g/dl (p less than 0.001); IVST and LVMI decreased to 1.42 +/- 0.35 cm (p less than 0.02) and 155.4 +/- 25.1 g/m2 (p less than 0.001); LVPWT and BP remained unchanged (1.30 +/- 0.26 cm and 146.8 +/- 16.9/81.2 +/- 7.8 mm Hg) at the end of the study. During the observation period, two groups of 5 and 7 patients differed from each other. The group of 5 patients had higher BP values (158.9 +/- 9.8/86.5 +/- 5.3 vs. 140.0 +/- 9.5/79.2 +/- 6.8 mm Hg, p less than 0.01), and the period with Hb values above 10 g/dl was shorter (14.5 +/- 2.4 vs. 17.8 +/- 2.4 months, p less than 0.05). These 5 patients failed to show a significant decrease in IVST and LVMI.(ABSTRACT TRUNCATED AT 250 WORDS)

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This report describes the case of a 24-year-old female heroin addict with large tricuspid valve vegetation, recurrent septic pulmonary emboli, and renal failure, due to immune-complex nephritis. The clinical course was initially complicated by acute hepatitis A. Because of recurrent emboli and persistent fever despite adequate antibiotic therapy she underwent excision of the vegetation ("vegetectomy") and tricuspid valvuloplasty. She was well at follow-up 12 months later with trivial tricuspid regurgitation shown by doppler-echocardiography. Kidney and liver function were normal. Right-heart endocarditis in drug addiction and therapeutic approaches are discussed. In selected cases "vegetectomy" and valvuloplasty offer a promising therapeutic alternative.

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