Evaluation of ventricular arrhythmias late after coronary artery bypass graft surgery--relation to clinical variables

This study was undertaken to evaluate ventricular arrhythmias (VA) using ambulatory ECG monitoring in 150 patients 33 +/- 22 months (mean +/- SD) after successful CABG in relation to severity of coronary artery disease (LS: Leaman score, Circulation 1981), revascularization ratio (RI: preop. LS-postop.LS/preop.LS), preoperative myocardial infarct size (Selvester score: SQS, Circulation 1982), LV function and other variables. They were divided into two groups according to the Lown classification; 42 patients with serious VA (group A: grade 4 to 5), and 108 without them (group B: grade 0 to 3). Group A was older than group B (60 +/- 5 vs. 57 +/- 9; p less than 0.05). There were no significant differences in follow-up period, coronary risk factors, LS and RI between the groups. Group A had significantly higher SQS (7.5 +/- 3.2 vs. 2.6 +/- 1.9; p less than 0.01), LVEDP (preop.: 14 +/- 7 vs. 11 +/- 5 mmHg; p less than 0.05, postop.: 14 +/- 7 vs. 11 +/- 5 mmHg; p less than 0.05), LVESVI (preop.: 53 +/- 27 vs. 31 +/- 17 ml/M2; p less than 0.01, postop.: 53 +/- 35 vs. 30 +/- 14 ml/M2; p less than 0.01), LVEDVI (preop.: 93 +/- 28 vs. 72 +/- 22 ml/M2; p less than 0.01, postop.: 90 +/- 36 vs. 74 +/- 21 ml/M2; p less than 0.01), and lower LVEF (preop.: 44 +/- 15 vs. 58 +/- 11%; p less than 0.01, postop.: 44 +/- 15 vs. 60 +/- 10%; p less than 0.01) than group B.(ABSTRACT TRUNCATED AT 250 WORDS)     

Regression of left ventricular hypertrophy after partial correction of anemia with erythropoietin in patients on hemodialysis: a prospective study.

Myocardial effects of recombinant human erythropoietin (rhEPO) treatment were prospectively investigated in 15 hemodialysis (HD) patients with severe anemia (hematocrit [Ht] 19.7 +/- 2.5%). Echocardiographic studies were performed after a midweek HD session just before and after a year of rhEPO. At the end of the study period, Ht had improved to 32.2 +/- 3.5% and cardiac index significantly decreased (5.48 +/- 1.54 vs 3.97 +/- 0.94 l/min/m2, p less than 0.001). Left ventricular mass index (LVMi) decreased with rhEPO (210.7 +/- 48.3 vs 139 +/- 50 g/m2, p less than 0.05). This decrease was concomitant with a decrease of LV end-diastolic diameter (4.89 +/- 0.44 vs 4.57 +/- 0.64 cm, p less than 0.05), interventricular septum thickness (IVST, 1.42 +/- 0.33 vs 1.07 +/- 0.13 cm, p less than 0.01) and LV posterior wall thickness (LVPWT, 1.28 +/- 0.21 vs 1.01 +/- 0.11 cm, p less than 0.01). Eight patients were hypertensive well controlled with hypotensive drugs (group I) and 7 normotensive (group II). LVMi was higher in group I than in group II before rhEPO (235.2 +/- 40 vs 182.7 +/- 43.1 g/m2, p less than 0.05) and significantly decreased after rhEPO in both groups (28.5% and 41.4% respectively). LVMi remained higher in group I than in group II at the end of the study (168.5 +/- 0.9 vs 106.7 +/- 24 g/m2, p less than 0.025). A moderately elevated IVST/LVPWT was reduced with a year of rhEPO (1.14 +/- 0.40 vs 1.05 +/- 0.15, p less than 0.05), disclosing correction of asymmetric septal hypertrophy. We conclude that left ventricular hypertrophy (LVH) regression is obtained after partial correction of anemia with rhEPO. Previous hypertension with current need of antihypertensive treatment has also a significant effect in the development of LVH. Whether this regression would improve outcome in HD patients remains to be established.     

Efficacy of modified ultrafiltration in coronary artery bypass grafting]

We evaluated the efficacy of modified ultrafiltration (MUF) in coronary artery bypass grafting. Twenty patients were divide into two groups consisting of a control group (n = 11) and a MUF group (n = 9). MUF was carried out for fifteen minutes immediately after the completion of cardiopulmonary bypass. The blood flow through the ultrafilter was 300 ml/min and about 1,200 ml of water was removed. The hematocrit elevated significantly from 25% to 30% in the MUF group (p < 0.01). Postoperative blood loss in the first 24 hours in the MUF group was significantly less than that in the control group (8 +/- 2 ml/kg vs 12 +/- 4 ml/kg, p < 0.01). There was no statistical difference in the percentage of the increase in body weight after the operation, inflammatory reaction and pulmonary function (A-a DO2, PaO2/FIO2 and duration of intubation) between two groups. In conclusion, MUF is useful to hemoconcentrate and reduce postoperative blood loss in coronary artery bypass grafting.     

Erythropoietin deficiency after coronary artery bypass procedures

Erythropoietin is the primary regulator of erythropoiesis. Erythropoietin has been shown to increase exponentially in response to linear decreases in hematocrit in normal, unstressed animals. However, the effect of operation, with its attendant stress, on erythropoietin levels is unknown. The purpose of this study is to evaluate the effect of surgical stress on erythropoietin. Twenty otherwise healthy patients scheduled for elective surgical procedures were studied. The cholecystectomy group included 10 patients who underwent cholecystectomy for documented stone disease. Ten patients who underwent coronary artery bypass procedures constituted the coronary artery bypass grafting group. Patients were studied preoperatively as well as on the first and second postoperative days. The hematocrit and erythropoietin levels were similar in both groups preoperatively. The hematocrit in the coronary artery bypass grafting group was lower than that of the cholecystectomy group on postoperative day 1 (0.31 versus 0.36; p less than 0.003) and postoperative day 2 (0.30 versus 0.36; p less than 0.001). During the first two postoperative days the erythropoietin levels were similar between groups. The data show that postoperative erythropoietin levels are similar after coronary artery bypass grafting, despite more severe anemia, when compared with cholecystectomy. This suggests that after coronary artery bypass grafting there is a relative deficiency of erythropoietin. Administration of recombinant human erythropoietin to patients undergoing surgical procedures could correct the erythropoietin deficiency and accelerate postoperative erythropoiesis.     

Erythropoietin therapy in pre-dialysis patients with chronic renal failure: lack of need for parenteral iron

BACKGROUND: During erythropoietin therapy, scant information exists regarding the optimal target percent saturation of transferrin (TSAT), ferritin and the mode and amount of iron supplementation in pre-dialysis patients with anemia due to chronic kidney disease (CKD). HYPOTHESIS: Pre-dialysis CKD patients may have different needs for iron supplementation than end-stage renal disease subjects during erythropoietin therapy. METHODS: Retrospective analysis of pre-dialysis CKD subjects (n = 31) treated with erythropoietin at our institution. RESULTS: In this population our results showed that target hematocrit (33-36%) was achievable with erythropoietin (mean subcutaneous dose 86 +/- 17 [SD] units/kg/week) without parenteral iron therapy. The hematocrit increased from a mean baseline value of 28.4 +/- 2.7 to 33.6 +/- 3.4% at time 1 (4-9 weeks, p < 0.0001), and to 37.7 +/- 4.5% at time 2 (10-20 weeks, p < 0.0001). The hemoglobin concentration increased from 9 +/- 0.9 g/dl at baseline to 10.7 +/- 1.1 g/dl at time 1 (p < 0.0001) and to 12 +/- 1.5 g/dl at time 2 (p < 0.0001). Subgroup analyses of patients prescribed <200 mg oral elemental iron per day (n = 10), those with TSAT <20% and/or ferritin <100 ng/ml (n = 19), and those prescribed erythropoietin <80 units/kg/week (n = 12), all showed a significant increase in hematocrit and hemoglobin. CONCLUSIONS: Our data show that pre-dialysis CKD subjects respond adequately to erythropoietin at or lower than recommended erythropoietin doses without parenteral iron. This response extends even to subgroups with TSAT and/or ferritin levels deemed to indicate iron deficiency in CKD subjects, and may be due to lack of existence of functional iron deficiency in this group of patients.     

Vasoactive drug effects on blood flow in internal mammary artery and saphenous vein grafts

The internal mammary artery is a dynamic coronary graft, whereas the saphenous vein graft is passive. Therefore, potential exists not only for beneficial vasodilation but also for catastrophic spasm of the artery. The purpose of this study was to examine blood flow in the internal mammary and saphenous vein grafts during infusion of drugs that are commonly used after cardiac operations. A canine right heart bypass preparation allowed precise control of cardiac output, blood pressure, and heart rate, which were maintained constant during drug infusion. Both the internal mammary and saphenous vein grafts were constructed so that they perfused the same coronary bed: They were anastomosed in a Y fashion to a ligated anterior descending coronary artery. Electromagnetic flow probes measured graft flow (with the other graft occluded) before and after 15 minutes of drug infusion. The order of drug infusion was randomized and changes were compared by tests for paired differences. Phenylephrine (2 micrograms/kg/min) decreased flow in both the internal mammary and saphenous vein grafts, whereas norepinephrine (0.1 microgram/kg/min) increased flow in both grafts. Epinephrine (0.05 microgram/kg/min) increased mammary artery flow 16% +/- 6% but decreased saphenous vein graft flow 9% +/- 7%. Nitroglycerin (1 microgram/kg/min) significantly increased internal mammary flow (36% +/- 13%), from 47 +/- 7 to 59 +/- 7 ml/min (p less than 0.01), whereas flow decreased significantly in the saphenous vein graft 14% +/- 3%, from 64 +/- 9 to 59 +/- 8 ml/min (p less than 0.01). Nitroprusside (1 microgram/kg/min) decreased mammary artery flow 12% +/- 2%, from 50 +/- 7 to 44 +/- 7 ml/min (p less than 0.01), but increased saphenous vein graft flow 25% +/- 8%, from 64 +/- 9 to 77 +/- 7 ml/min (p less than 0.01). All hemodynamic variables were unchanged, except for norepinephrine, which significantly increased the first derivative of left ventricular pressure. The results suggest that flow through the canine internal mammary artery is changed by the drugs commonly used in perioperative management. Epinephrine and nitroglycerin increased internal mammary artery flow and decreased saphenous vein graft flow, whereas nitroprusside had the opposite effect. The vascular reactivity of the internal mammary artery must be considered when these drugs are used after coronary revascularization.     

Exercise response assessed by continuous monitoring of ventricular function in patients with coronary bypass operations.

The response of left ventricular function during exercise and recovery after exercise was assessed in 35 patients with coronary artery bypass grafting before and after the operation by means of a continuous ventricular function monitor, which records serial beat-to-beat radionuclide data and calculates left ventricular ejection fractions every 20 seconds. The mean ejection fraction decreased with graded bicycle exercise from 48% +/- 9% to 41% +/- 11% (p less than 0.001) before operation but increased with exercise from 50% +/- 9% to 55% +/- 11% (p less than 0.001) after operation. Cardiac response was divided into four types with respect to the profiles of the ejection fractions during exercise. Type A continued to increase; type B initially increased but then decreased in late exercise stages; type C did not change significantly; type D continued to decrease. Most patients had type C or D responses before operation but type A after operation. Seven patients with occluded grafts or ungrafted coronary arteries had type B or D responses. Three patients with complete revascularization, including an internal thoracic artery and saphenous vein grafts, had type B responses. Three patients with extensive infarction and poor left ventricular function showed type C. In the early recovery period after exercise, most patients had an "overshoot" elevation of ejection fraction. The mean value increased from 59% +/- 10% before operation to 64% +/- 11% after operation (p less than 0.01). The recovery time after exercise was reduced from 2.8 minutes before operation to 1.8 minutes after operation (p less than 0.001). The continuous ventricular function monitor elucidated changes in left ventricular function both during exercise and recovery after exercise, as well as unmasking abnormalities in left ventricular function after coronary bypass operation.     

Hemodialysis and continuous ambulatory peritoneal dialysis effects on erythropoiesis in renal failure

Parameters of erythropoiesis were studied in patients with endstage renal disease established on continuous ambulatory peritoneal dialysis (CAPD) and regular hemodialysis treatment (RDT). Serum erythropoietin was measured by radioimmunoassay, and erythroid progenitor cell (CFU-E) formation was assayed in fetal mouse liver cultures. Serum erythropoietin concentrations in both CAPD (35.3 +/- 4.0 mU/ml) and RDT (31.9 +/- 1.9 mU/ml) patients were significantly higher (P less than 0.01) than normal values (23.1 +/- 1.0 mU/ml). The serum erythropoietin concentration did not correlate with either hematocrit or inhibition of CFU-E formation in either group of dialysis patients. In both CAPD and RDT patients the hematocrit correlated significantly (P less than 0.001) with the degree of serum inhibition of CFU-E formation. CFU-E formation decreased from 74.5 +/- 2.5 to 62.5 +/- 3.5% of control with increasing concentrations of uremic serum in cell cultures from 5 to 20%. In RDT patients a single hemodialysis produced a decrease in the mean serum erythropoietin concentration from 31.8 +/- 2.1 to 27.4 +/- 1.8 mU/ml (P less than 0.01) but no significant change in CFU-E formation. In conclusion, although serum immunoreactive erythropoietin levels are elevated above the normal range in dialysis patients, the response remains inadequate for the severity of the anemia, and it is the degree of serum inhibition of erythropoiesis in both CAPD and RDT patients which correlates with and possibly determines the degree of anemia.     

Effect of erythropoietin treatment on physical exercise capacity and on renal function in predialytic uremic patients.

Anemia is already present in patients with moderate renal failure and is a major cause of the decline in exercise capacity seen in these patients. We examined the effects of erythropoietin (EPO) treatment in 12 predialytic uremic patients (EPO group: mean age 46 +/- 12 years; 6 men, 6 women) with a mean glomerular filtration rate (GFR) of 10 +/- 4 ml/min x 1.73 m2. These patients were compared to a control group of 8 patients (5 men, 3 women). The observation period was 3 months. The EPO group received 300 U/kg body weight i.v. once a week. The EPO group increased their total hemoglobin (THb) from 323 +/- 89 to 466 +/- 128 g (p less than 0.001) and their hemoglobin concentration from 86 +/- 8 to 117 +/- 11 milligrams (p less than 0.001). Their exercise capacity, measured by a standardized exercise test on a bicycle ergometer, increased from 128 +/- 45 to 147 +/- 57 W (p less than 0.01). The control group did not change their THb (349 +/- 124 and 357 +/- 131 g), hemoglobin (93 +/- 8 and 94 +/- 10 milligrams) or exercise capacity (98 +/- 49 and 101 +/- 50 W) during the observation period. There was a significant correlation between the increase in THb and the increase in exercise capacity in the EPO group (r = 0.81, p less than 0.005). The GFR was unchanged in both groups (EPO group: 10 +/- 4 and 10 +/- 6 ml/min x 1.73 m2; control group: 8 +/- 3 and 8 +/- 3 ml/min x 1.73 m2).(ABSTRACT TRUNCATED AT 250 WORDS)     

Chlamydia pneumoniae infection and accelerated development of coronary artery disease in patients with chronic renal failure.

AIMS: This study examined the relationship between Chlamydia pneumoniae (C. pneumoniae) infection and the accelerated development of coronary artery disease (CAD) in patients with chronic renal failure (CRF). METHODS: Two-hundred and fourteen patients undergoing coronary angiography, including 67 controls and 147 patients with CAD (97 without CRF and 50 with CRF), were enrolled in this study. Anti-C. pneumoniae specific IgG and IgA antibodies were measured using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Coronary artery disease (expressed as CAD score) was more severe in patients with than without CRF (14.9 +/- 6.0 vs. 11.3 +/- 6.0, p < 0.01). Seropositive rates of IgG and IgA antibodies against C. pneumoniae were higher in all CAD patients than in the controls (76.2% vs. 44.8%, p < 0.001 for IgG; 59.9% vs. 40.3%, p < 0.01 for IgA). In both CAD subgroups, IgG seropositive rates were similarly elevated (82.0% and 73.2% vs. 44.8% for control, p < 0.001, respectively), whereas those of IgA were significantly elevated only in CAD with CRF (68.0% vs. 55.7% for control, p < 0.01). The mean antibody index of IgG was elevated in all CAD patients compared with the controls (1.9 +/- 1.0 vs. 1.3 +/- 0.9, p < 0.0001), but that of IgA was not (1.5 +/- 1.0 vs. 1.2 +/- 0.9). Levels of IgG were elevated in all patients with CAD compared with the control (2.4 +/- 1.1 and 1.8 +/- 1.0 vs. 1.3 +/- 0.9, p < 0.001 and p < 0.001, respectively), whereas those of IgA were elevated only in CAD with CRF (1.8 +/- 1.1 vs. 1.2 +/- 0.9, p < 0.05). Stepwise logistic regression analysis revealed that the elevated IgG antibody index was an independent risk factor for CAD regardless of CRF (odds ratios 1.9, 1.8, and 2.3), whereas the IgA index was a risk factor only in CAD with CRF (odds ratio 1.7). CONCLUSIONS: Chlamydia pneumoniae infection may be related to the accelerated CAD in patients with CRF, which was specifically suggested by an elevated IgA level. In other words, the prevalence of active C. pneumoniae infection is higher in patients with CAD and CRF than that in those with CAD without CRF.     

Hemodynamic changes in hemodialyzed patients during treatment with recombinant human erythropoietin

Evolution of cardiac index in 12 patients with severe renal anemia on regular hemodialysis (hematocrit 19.9 +/- 2.8%) was studied during the first 4 months of treatment with recombinant human erythropoietin (rhEPO). At the end of the study period, hematocrit rose to 31.1 +/- 3.5% (p less than 0.001) and cardiac index significantly decreased (5.34 +/- 1.25 vs. 3.81 +/- 0.84 liters/min/m2, p less than 0.001). Cardiac index fell mainly because of reduction of stroke volume (108 +/- 27 vs. 81 +/- 25 ml, p less than 0.001), while heart rate did not change during the study period. Before starting rhEPO cardiac index was elevated in 11 out of the 12 patients, whereas after 4 months of treatment this was only maintained in 4 of them. We conclude that substitution with rhEPO in hemodialysis patients significantly decreases cardiac index, confirming anemia as the main factor for hyperdynamic circulatory state in these patients. Whether this reduction in cardiac index will ameliorate cardiac morbidity or not and hematocrit levels for achieving the major benefits require further studies.     

Effects of coronary revascularization on infarcted myocardial regions--evaluation on postoperative left ventricular regional wall motion during exercise

In order to determine the effects of coronary revascularization for infarcted regions on postoperative left ventricular function and regional wall motion, we studied first-pass radionuclide angiography at rest and during exercise before and after operation in 18 patients with previous myocardial infarction. Preoperative mean value of left ventricular ejection fraction (LVEF) was significantly decreased during exercise from 56.8 +/- 14.1% to 46.1 +/- 15.5% (p less than 0.01). Postoperatively, there was no change of the values between at rest and during exercise: 53.6 +/- 14.1% versus 51.9 +/- 15.7%. Postoperative mean LVEF during exercise was significantly higher, compared with that of preoperative LVEF (p less than 0.05). Mean regional ejection fraction of infarcted regions was significantly decreased during exercise from 66.0 +/- 15.0% to 56.1 +/- 15.8% (p less than 0.01) before operation. However, there was no significant change in values between at rest and during exercise after operation: 65.4 +/- 13.9% versus 61.8 +/- 14.5%. Mean postoperative regional ejection fraction during exercise was significantly higher, compared with preoperative regional ejection fraction after operation (p less than 0.05). These results might be indicated that regional wall motion of the infarcted regions with ischemia enhanced by exercise preoperatively can be definitely improved by coronary revascularization.     

Factors influencing physical working capacity in renal transplant patients

Clyne N, Jogestrand T, Lins L-E & Pehrsson SK. Division of Nephrology and Cardiology, Department of Medicine and Department of Clinical Physiology, Karolinska Hospital, Stockholm, Sweden. We have examined uraemic patients' exercise capacity, and the factors influencing this capacity, before and after successful renal transplantation. Eleven uraemic patients (mean age 41 +/- 10 years) with an average glomerular filtration rate (GFR) of 5 +/- 4 ml/min x 1.73 before and 45 +/- 19 ml/min x 1.73 after transplantation participated in the study. The maximal exercise capacity, measured by standardized exercise test on a bicycle ergometer, averaged 106 +/- 25 W before and 126 +/- 35 W (p less than 0.05) after transplantation. The patients interrupted the tests prior to and after transplantation because of general fatigue, leg tiredness or both. No patient experienced angina pectoris. All, but one, had a normal ECG reaction during exercise. Total haemoglobin (THb) was 55 +/- 8% of the expected normal before and 84 +/- 19% after transplantation (p less than 0.01). The increase in working capacity was linearly correlated to the increase in THb (r = 0.84, p less than 0.01), but not to the improvement in GFR nor to the decrease in parathyroid hormone. In conclusion, successful renal transplantation improves working capacity. The results indicate that an increased THb is a major determinant for this increase in working capacity.     

Prediction of perioperative cardiac complications by electrocardiographic monitoring during treadmill exercise testing before peripheral vascular surgery

ECG monitoring during treadmill exercise testing was performed in a prospective series of 105 consecutive patients with intermittent claudication scheduled for peripheral vascular surgery. ECG monitoring during the exercise test was useful in predicting perioperative cardiac complications. In 55 patients with evidence of coronary artery disease by history and ECG obtained at rest, a strong association (p less than 0.001) between an ischemic response to exercise testing and the occurrence of perioperative cardiac events was observed. ECG monitoring during the exercise test also revealed previously unsuspected ischemia or arrhythmias in six of the remaining 50 patients and predicted perioperative cardiac problems in four of these six. An ischemic response to low-level treadmill exercise testing probably indicates advanced coronary artery disease and offers valuable predictive information when a revascularization procedure is considered for the relief of intermittent claudication.     

Measurement of regional myocardial blood flow. Application of the electrolytic hydrogen clearance method in man

To assess myocardial perfusion intraoperatively and to evaluate the adequacy of coronary bypass grafting, we measured regional myocardial blood flow by the electrolytic hydrogen clearance method in 49 patients. Group I comprised 10 patients with nonischemic heart disease and group II, 39 patients with ischemic heart disease undergoing coronary bypass grafting. Group II was subdivided according to the percent stenosis of the coronary arteries supplying the ventricular regions: group IIa, less than 75% stenosis; group IIb, greater than or equal to 75% stenosis. Mean myocardial blood flows were 154 +/- 7, 145 +/- 5, and 98 +/- 9 ml/min/100 gm in groups I, IIa, and IIb, respectively (p less than 0.01, group IIb versus groups I and IIa). Mean blood flows were 161 +/- 19, 159 +/- 12, 78 +/- 12, and 59 +/- 15 ml/min/100 gm in areas of the left anterior descending coronary artery with less than 50%, 75%, 90%, and 99% stenosis in group II. In areas with a totally occluded left anterior descending coronary artery with collaterals, mean flow was 90 +/- 15 ml/min/100 gm. The mean myocardial blood flows were 40 +/- 7 and 100 +/- 14 ml/min/100 gm in areas with anterior Q wave and non-Q wave infarction, respectively (p less than 0.01). After cardiopulmonary bypass, the mean flow increased from 99 +/- 11 to 150 +/- 7 ml/min/100 gm in the grafted areas in group IIb (p less than 0.01), but it did not change in group I or IIa. The electrolytic hydrogen clearance method provided quantitative evaluation of myocardial perfusion and recovery from hypoperfusion by coronary bypass grafting. This method was especially useful in patients undergoing mammary artery grafting.     

Trends in invasive treatment of single-vessel and double-vessel coronary disease

We examined our practice of invasive therapy for one- and two-vessel coronary disease to assess the impact of the randomized trials of coronary surgery and the current use of angioplasty. We first reviewed our results with coronary artery bypass graft in equivalent patients in the Coronary Artery Surgery Study with one- and two-vessel disease between 1976 and 1981. Among 1376 patients, hospital mortality was 0.07%, and 5-year survival was 95.2% +/- 0.8%. To define trends in invasive therapy, which have since occurred, we compared 100 patients with one- and two-vessel disease in each of three groups: 1979 coronary artery bypass graft, 1984 coronary artery bypass graft, and 1984 percutaneous transluminal coronary angioplasty. Preoperative characteristics in the average 1979 and 1984 patients were similar; however, in 1984, patients who had a coronary artery bypass graft were older than patients who had percutaneous transluminal coronary angioplasty (61.5 versus 56.7 years, p less than 0.01), they required more heart medications (2.1 versus 1.5, p less than 0.01), had more previous infarctions (0.8 versus 0.5, p less than 0.01), and more patients had an ejection fraction of less than 50% (34% versus 7%, p less than 0.01). Patients who had angioplasty had a shorter postoperative stay (median number of days 7, 7, 2, p less than 0.01). Freedom from major complications was similar among the groups (91%, 87%, 85%). Unstable symptoms were the most frequent indication for invasive therapy (approximately 80%), whereas long-term symptoms, those considered in the randomized trials, occurred in relatively few patients. The number of patients without at least one definite indication for invasive therapy was 13%, 3%, and 11%, p less than 0.05, suggesting that the indications for the 1984 coronary artery bypass graft group have become more restrictive since the 1979 coronary artery bypass graft group. Indications for the 1984 percutaneous transluminal coronary angioplasty group remained less restrictive, being similar to those for the 1979 coronary artery bypass graft group. A continuing trend toward the use of percutaneous transluminal coronary angioplasty was evident, as 56% of the 1979 coronary artery bypass graft group of patients and 32% of the 1984 coronary bypass group of patients would be offered percutaneous transluminal coronary angioplasty rather than coronary artery bypass graft on the basis of 1986 percutaneous transluminal coronary angioplasty criteria. The p values were obtained with analysis of variance or chi 2 test.     

Comparison of intravenous ganciclovir and cytomegalovirus hyperimmune globulin pre-emptive treatment in cytomegalovirus-positive heart transplant recipients.

BACKGROUND: We compared the use of intravenous ganciclovir and cytomegalovirus hyperimmune globulin (CMVIG) as a pre-emptive treatment for cytomegalovirus (CMV)-positive heart transplant recipients. METHODS: Of 59 CMV-seropositive adult heart transplant recipients enrolled in Group 1, 37 tested positive for pp65 antigen within 12 weeks post-transplantation. These patients were randomized to receive either intravenous ganciclovir (n = 23) or CMVIG (n = 14). Group 2 included 133 CMV-seropositive heart transplant recipients who were not tested for CMV antigenemia and who received no anti-CMV therapy. RESULTS: CMV disease developed in 0 of 59 patients from Group 1, and in 27 of 133 patients (20%) in Group 2 (p = 0.0001). The incidence of superinfections was lower in Group 1 (0.28 +/- 0.46) than in Group 2 (1.10 +/- 1.33) (p = 0.01). The 2 groups did not differ with regard to incidence of rejection (0.7 +/- 0.9 in Group 1 vs 1.0 +/- 1.2 in Group 2; p = NS), transplant coronary artery disease at 1 year (14% in Group 1 vs 16% in Group 2; p = NS) or post-transplant lymphoproliferative disease (0% in Group 1 vs 2% in Group 2; p = NS). Ganciclovir and CMVIG therapies were associated with similar rates of rejection (0.52 +/- 0.6 with ganciclovir vs 0.50 +/- 0.60 with CMVIG; p = NS), superinfection (0.30 +/- 0.48 with ganciclovir vs 0.25 +/- 0.46 with CMVIG; p = NS), and transplant coronary artery disease at 1 year (13% with ganciclovir vs 14% with CMVIG, p = NS). CONCLUSIONS: The pre-emptive anti-CMV approach is superior to prophylaxis in CMV-seropositive heart transplant recipients. Both ganciclovir and CMVIG are equally effective.     

Long-term therapy for postrenal transplant erythrocytosis with ACE inhibitors: efficacy, safety and action mechanisms

SUBJECTS AND METHODS: Eleven patients with postrenal transplant erythrocytosis were treated with angiotensin-converting enzyme inhibitors for 18 months. RESULTS: Indices of red blood cell production and destruction, renal function and kalemia were followed-up during the treatment. Angiotensin-converting enzyme inhibitors (ACEi) led to a progressive and significant fall in hemoglobin and hematocrit compared to the basal values at every time interval considered with a maximum reduction at 12th month for hemoglobin ( 17.04 +/- 0.21 vs. 15.10 +/- 0.42 g/dl, p < 0.0001) and at the 6th month for hematocrit (53.74 +/- 0.56 vs. 45.7 +/- 1.19 %, p < 0.0001). Serum erythropoietin levels were reduced significantly after the first month of therapy (13.56 +/- 2.7 vs. 7.48 +/- 1.6 mUI/dl, p < 0.05) after which no further variations were recorded. In the course of ACEi therapy, there was an inverse correlation between percentage reduction in erythropoietin values and those of hemoglobin emerged (r = 0.24, p < 0.05) and hematocrit (r = 0.39, p < 0.01). Indices of red blood destruction including haptoglobin, bilirubin and lactic dehydrogenase, were unaffected by ACE inhibitors treatment, as was creatininemia and kalemia. Treatment was well tolerated by all patients who completed the study without major adverse side-effects. No patient required phlebotomy and no thromboembolic event occurred during angiotensin-converting enzyme therapy. CONCLUSIONS: Our results suggest that angiotensin-converting enzyme inhibitors are a safe and effective long-term therapy of postrenal transplant erythrocytosis. These agents decrease the erythropoietin synthesis but this effect is not the sole mechanism by which angiotensin-converting enzyme inhibitors act in postrenal renal transplant erythrocytosis.     

Should obese patients not undergo coronary artery surgery?

To assess the effect of obesity on the patient's recovery from coronary artery bypass surgery, a prospective study was performed on 200 patients. Group 1 comprised 101 nonobese patients and group 2, 99 obese patients. The mean percentage over the ideal weight was 8.2% in group 1 and 33.4% in group 2 (p less than 0.001). Preoperative assessment revealed no difference in age, sex, height, incidence of diabetes, family history or smoking habits between the two groups. Group 2 had a higher incidence of hypertension (p less than 0.01) and hyperlipidemia (p less than 0.02). The average number of grafts placed per patient was 3.4 +/- 0.8 in group 1 and 3.5 +/- 0.08 in group 2. Operative mortality was 2.9% and 2.0% in groups 1 and 2 respectively. Obesity was a predictive factor in postoperative hypertension (p less than 0.025), in the development of wound infection (p less than 0.01) and in an increased requirement of bronchodilators (p less than 0.01). The postoperative progression of physical activity and length of hospital stay was similar, being 10.9 +/- 5.8 days and 9.7 +/- 9.5 days in groups 1 and 2 respectively. The authors conclude that bypass grafting is an acceptable therapeutic option for obese patients with coronary artery disease.     

Long-term follow-up of exercise tolerance after coronary bypass grafting]

Six hundred forty-eight serial graded exercise tests were performed on 400 patients up to 10 years after coronary bypass graftings (CABG). The maximal attained exercise tolerance, over 10 METS, were observed in 60% of patients and the negative response to exercise test in 43% of patients. The positive response in various parameters were observed at the following rates: graft occlusion-30% vs graft patent-46% (p less than 0.01); incomplete revascularization-39% vs complete revascularization-22% (p less than 0.01); and less than or equal to 8 METS 4-45% vs greater than or equal to 10 METS-28% (p less than 0.01), respectively. However, no significant difference was observed among number of vessels diseased, number of graftings, and presence of old myocardial infarction. The maximal attained stage of exercise, over 10 METS, in various parameters were at the following rates: less than or equal to 59 years old-70% vs greater than or equal to 60 years old-44% (p less than 0.01); male-63% vs female-32% (p less than 0.01); and graft patent-63% vs graft occlusion-50% (p less than 0.05), respectively. The serial analysis of exercise test demonstrated that improved exercise tolerance appears to persist for at least 5 years after CABG. However, the patients in complete revascularization had a tendency to increase the rate of positive response. In conclusion, the completeness of revascularization as well as graft patency was the main factor limiting exercise tolerance, and correlates with the extent and the duration of improvement after CABG.