Acute effects of nitroglycerin on the energetics of the human left ventricular myocardium

We analyzed performance and efficiency of the left ventricular myocardium on the basis of two new energetic parameters. The myocardial energy consumed during one cardiac cycle is related to performed work on the one hand (E1) and to the stress-time-integral on the other (E2). E1 was obtained by analysis of the pressure-volume integral divided by left ventricular muscle mass. E2 was obtained as follows: the stress-time integral was analyzed from pressure-volume data and wall thickness using an ellipsoidal calculation model. In order to transfer the stress-time integral into energy units, the value was multiplied by a constant factor which was obtained in experimental myothermal studies. In ten patients with coronary heart disease undergoing diagnostic heart catheterization, angiocardiography was performed before and after oral administration of nitroglycerin (1.6 mg). Total energy consumption (2E1 + E2) per gram myocardium per beat decreased from 6.1 +/- 1.3 mcal/g to 4.7 +/- 1.4 mcal/g (P less than 0.01), and myocardial efficiency (E1/[2E1 + E2]) increased from 27.0 +/- 3.1% to 28.4 +/- 4.3% (N.S.) on the average. This analysis explains quantitatively the beneficial effect of nitro-preparations on myocardial function and energetics.     

Peritoneal morphology in children treated by continuous ambulatory peritoneal dialysis

Fifty peritoneal biopsies (PB) from 35 patients with end-stage renal disease, treated by continuous ambulatory peritoneal dialysis (CAPD) and aged 2 months to 18 years, were examined by light microscopy (n=50) and/or scanning electron microscopy. PB were performed during surgical procedures immediately before the start of, during, or after the cessation of CAPD treatment. PB from 15 children without renal disease undergoing laparatomy were examined similarly. Before the start of CAPD, a scarcity and shortening of the mesothelial microvilli was observed by scanning electron microscopy. During and after CAPD, variable alterations of mesothelium, interstitium and capillaries were found. The mesothelial layer was absent in all 5 PB obtained during episodes of active peritonitis. In patients treated by CAPD for longer than 6 months, mesothelial denudation was observed more frequently (6/11) than in children treated for shorter periods (1/7) (P<0.08). Fibrosis of the peritoneal membrane was present in about 50% of patients during or after the cessation of CAPD without impairment of peritoneal function. No correlation was found between the presence of fibrosis and the frequency of peritonitis or the duration of CAPD treatment.     

Toxic drug-induced hyposmia with lovastatin]

We present the first case of hyposmia after application of lovastatin. Unclear disorders of smell should prompt a detailed drug anamnesis.     

Papillarmuskelri? w?hrend eines Belastungs-EKGs nach Myokardinfarkt

The case of a 57 year old patient is reported, who suffered from an acute myocardial infarction with maximum CK and CKMB values of 821 and 84 U/l, respectively. The patient underwent bicycle exercise testing 9 days after a myocardial infarction in 25 W steps every 2 min starting with 50 W. The ergometry was interrupted at 125 W because of ST segment depression of 0.28 mV in V6. Systolic blood pressure dropped to 55 mm Hg, combined with severe angina and shock. Volume substitution and catecholamines did not elevate blood pressure. Immediate M-mode and Doppler echo revealed a "stiletto"-shaped mitral regurgitation profile typical of acute mitral valve insufficiency. The transesophageal echocardiogram showed a distinct mass moving between the left ventricle and left atrium, diagnostic of papillary muscle rupture. Despite of shock, mitral valve replacement was performed successfully. To our knowledge, this is the first report of a papillary muscle rupture during exercise testing after myocardial infarction. Papillary muscle rupture can be induced by exercise. This fateful event may not be predicted by the course of the ergometry. In case of hypotension during exercise, papillary muscle rupture should be considered. The diagnosis is to be established by transesophageal echocardiography.     

Pulmonary artery pressure and left ventricular late diastolic pressure in rest and during dynamic load. Comparative studies on pressure transmission in the pulmonary circulation during simultaneous determination]

Left ventricular enddiastolic pressure (LVEDP), mean pulmonary artery pressure (PAPM) and enddiastolic pulmonary artery pressure (PADP) were simultaneously recorded in 19 subjects with normal left ventricular (LV) function, and in 109 patients with LV-dysfunction, 83 of whom were also studied during exercise. Patients with valvular heart disease or atrial fibrillation were excluded from this study. LVEDP and mean pulmonary capillary wedge (PCW) pressure were simultaneously recorded in 81 patients at rest, andin 16 patients also during exercise; the LV diastolic pressure prior to atrial contraction (LVPpreA) could accurately be identified in 45 patients at rest and in 23 patients with exercise. In contrast to the widely accepted opinion of others, the PADP (mean 8.2 +/- 2.2 mm Hg at rest and 12.3 +/- 3.4 mm Hg with exercise) showed a close approximation of LVEDP (10.0 +/- mm Hg at rest and 16.2 +/- 3.5 mm Hg with exercise) only in normal subjects at rest (p less than 0.05 and p less than 0.01 respectively). In patients with LV dysfunction there was no significant difference between PADP (11.7 +/- 4.5 mm Hg and 23.0 +/- 8.9 mm Hg), PCW (11.6 +/- 5.1 mm Hg and 24.1 +/- 11.9 mm Hg) and LVPpreA (12.5 +/- 5.5 and 21.5 +/- 7.7 mm Hg) at rest and during exercise. LVEDP could be estimated with sufficient accuracy only from the PAPM (18.9 +/- 6.5 and 35.7 +/- 10.8 mm Hg). The increase in LVEDP (14.7 +/- 7.7 mm Hg) with exercise was not significantly different from the increase in PAPM (16.8 +/- 7.1 mm Hg). There were highly significant correlations (p less than 0.001) between LVEDP and PADP (r = 0.85) as well as PAPM (r = 0.86) at rest and during exercise with the regressionline being closest to the line of identity for LVEDP and PAPM. The pressure gradient between LVEDP and PADP (LVEDP - PADP = 6.3 mm Hg with exercise) equaled the pressure increase in LV by atrial contraction (LVEDP - LVPpreA = 6.3 and 13.3 mm Hg). The pressure difference between PADP or PAPM and LVEDP remained constant despite marked variation of other hemodynamic parameters, e.g. stroke volume index (SVI), heart rate (HR) and cardiac index(CI). These data suggest that an elevated LVEDP is caused mainly by an augmented atrial contraction in patients with LV dysfunction at rest and with exercise. This mechanism precludes an enddiastolic pressure equilibrium between pulmonary artery and left ventricel. PAPM allows the best estimation of LVEDP independent from other hemodynamic variables.     

Calcium acetate versus calcium carbonate as oral phosphate binder in pediatric and adolescent hemodialysis patients

Calcium carbonate is widely used as an oral phosphorus binder to control hyperphosphatemia in children on maintenance hemodialysis. Intestinal calcium absorption may induce hypercalcemia, particularly if calcitriol is given simultaneously. In adults, calcium acetate binds phosphorus more effectively than calcium carbonate, while reducing the frequency of hypercalcemic events. We therefore compared calcium acetate with calcium carbonate in nine pediatric patients on long-term maintenance hemodialysis. Following a 1-week withdrawal of phosphorus binders, calcium carbonate was administered for 7 weeks; after a second withdrawal, calcium acetate was given for another 7 weeks. All patients received calcitriol regularly. Both agents lowered the serum phosphorus concentration significantly (calcium carbonate 5.7±1.4 vs. 7.7±2.1 mg/dl, P<0.005; calcium acetate 5.8±1.4 vs. 7.8±2.0 mg/dl, P<0.005). Significantly less elementary calcium was ingested with calcium acetate than with calcium carbonate: 750 (375 – 1,500) vs. 1,200 (0 – 3,000) mg calcium/day, P<0.0001. With calcium carbonate serum calcium increased significantly. The number of episodes of hyperphosphatemia or hypercalcemia did not differ between treatments. Intact plasma parathyroid hormone (PTH) decreased significantly with both phosphate binders, and serum 25-hydroxyvitamin D₃ increased. There was a close relationship between serum phosphorus and PTH in prepubertal but not in pubertal patients. We conclude that hyperphosphatemia can be controlled effectively by both calcium acetate and calcium carbonate in pediatric hemodialysis patients. The oral load of elementary calcium is reduced significantly by binding phosphorus with calcium acetate instead of calcium carbonate; nevertheless, hypercalcemic episodes remain equally frequent with both phosphate binders. Received May 9, 1995; received in revised form and accepted February 23, 1996     

Audit and quality control in angioplasty in Europe: procedural results of the AQUA Study 1997: assessment of 250 randomly selected coronary interventions performed in 25 centres of five European countries. AQUA Study Group, Nucleus Clinical Issues, Working Group Coronary Circulation, of the European Society of Cardiology.

AIMS: Percutaneous transluminal coronary angioplasty (PTCA) has become the most widely used major intervention in western medicine. However, there is disparate use of this technique among different European countries and the U.S.A. In an attempt at quality assurance, the working group Coronary Circulation of the European Society of Cardiology has carried out a study on appropriateness, necessity, and performance of PTCA in Europe. The present paper reports on the procedural results of this survey. METHODS: In a multicentre case-control study in Europe, 750 patients (544 men, 206 women) with documented vascular disease of the From the countries participating in the European Registry of Coronary Intervention, the three countries with the highest absolute PTCA volume (Germany, France, and the United Kingdom) and two randomly selected countries (Belgium and Italy) were chosen for investigation. In these countries, five centres were selected at random according to the following criteria: one centre with >1000, three centres with 300-1000, and one centre with <300 procedures per year. In each of these, 10 cases from the first half of 1997 were randomly identified and all pertinent documentation was collected. RESULTS: In 250 cases, 325 stenoses were addressed as target lesions. Single vessel disease was present in 41%. History included stable angina in 49%, unstable angina in 32%, atypical chest pain in 6%, no anginal pain in 12%, and acute/subacute myocardial infarction in 13%. The percentage of patients with either positive stress test and/or unstable angina, acute/subacute infarction, previous infarction (within 6 months) or coronary revascularization amounted to 98%. Single vessel intervention accounted for 90%. In 41% balloon-only angioplasty was performed and in 54% at least one stent was implanted with considerable variation among countries. The use of other new devices amounted to only 3%. In 92%, the operators documented a successful procedure. Major complications (myocardial infarction, emergency bypass surgery, or death) were found in 4.8%. CONCLUSIONS: Based on scrutinized hospital and operator data, the present study revealed a satisfactorily high percentage of justifiable indications, an adequate procedural success rate, and an acceptably low complication rate. Further analysis by an expert panel will address appropriateness, necessity, and procedural performance of the individual cases.     

Low-dose cyclosporin A therapy in cadaver renal transplantation in children

Abstract. Fifty-one pediatric patients undergoing a first cadaveric kidney transplantation were followed for at least 2 years after grafting. They were divided into two groups: those treated with methylprednisolone plus azathioprine (AZA) and those treated with methylprednisolone plus low-dose cyclosporin A (CyA; median dose 109 mg/m²per day ± 3. 4 mg/kg per day after 1 year). The steroid dosage given was significantly lower in the second group. The 4-year graft survival rate was 68% for the AZA group and 78% for the CyA group. Renal function did not differ significantly in the two groups; after 1, 2, and 3 years, the median 24-h creatinine clearance was 79, 69, and 51 ml/min/1. 73 m² respectively, for the AZA group and 78, 63, and 68 ml/min/1. 73 m² respectively, for the CyA group. Linear growth was similar in the two groups. We conclude that in pediatric patients the results of low-dose CyA immuno-suppression do not differ significantly from those obtained with AZA in terms of graft survival, renal function, or growth.     

Treatment of in-stent restenosis with sirolimus-eluting-stents: results from the prospective German Cypher stent registry

Aims  Drug-eluting stents have been reported to effectively reduce in-stent restenosis (ISR). However, the effectiveness and safety have yet been investigated only in small trials or case series. The aim of this prospective large scale registry was to show that treatment of ISR with sirolimus eluting stents (SES) is safe, effective and feasible in daily routine. Methods and results  The German Cypher registry prospectively enrolled 6,555 patients undergoing implantation with SES for various indications, including 1,533 patients treated for ISR. Follow-up data (median 6.6 months) of this cohort was available for 1,531 patients (99.8%). Of these patients 75.8% were male. Of these patients 36.5% (n = 552) presented with acute coronary syndromes. In total, 1,932 SES were used with successful implantation in 98.9%. MI during hospitalization was observed in 0.7% (n = 11) while in-hospital mortality was only 0.1% (n = 2). MACE-rate at follow-up was 13.8% (n = 211) including a mortality of 1.3% (n = 20) and MI in 1.9% (n = 29). Total revascularization procedures including CABG (1.7%) were necessary in 12.3% (n = 186). Target vessel revascularization (TVR) rate was 9.3% (n = 139) and thus similar to patients with de novo lesions (8.1%, P = 0.69). Ten patients (0.65%) suffered from subacute stent thrombosis Vs. 0.24% observed in patients with de novo lesions (P = 0.03). Conclusion  This large registry confirms that treatment of ISR with sirolimus-eluting-stents is effective and save with good clinical results at index procedure and follow-up. TVR was not different from de novo lesions.