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F Pileggi

Publications and source records attributed to F Pileggi.

At least 55 records · Page 3Linked to original sources
PubMed1996

[Bacterial infections in 100 patients submitted to heart transplantation].

PURPOSE: To evaluate clinical findings and etiology of bacterial infections diagnosed in 100 consecutive heart transplantations. METHODS: One hundred consecutive heart transplant patients were studied. Follow-up after heart transplantation varied from 3 to 90 (mean 25.38 +/- SD 25.97) months. Etiology of bacterial infection was established using the Centers for Disease Control criteria. RESULTS: Bacterial infection was the most common cause of infection after heart transplantation; diagnosis was difficult. Infection sites were skin, mucous, membranes, soft tissue, surgical scar, pericardial and pleural spaces, soft tissue around heart pacing devices, urinary tract; bacteremias and endocarditis were also found. All bacterial agents recovered were fully identified. CONCLUSION: Bacterial infections are the most common infections in the first month after heart transplantation. They are important and also common after the treatment of the rejection episodes. Rapid diagnosis and adequate treatment are essential to prevent morbidity and death.

Adolescent↗
PubMed1996

Mid-term results of heart transplantation, cardiomyoplasty, and medical treatment of refractory heart failure caused by idiopathic dilated cardiomyopathy.

BACKGROUND: Heart transplantation is the surgical procedure of choice for treatment of refractory heart failure. However, it benefits a small number of patients because of the limited number of donors and selection criteria of recipients. Cardiomyoplasty is an alternative surgical procedure for heart failure. The aim of this investigation was to report our experience with heart transplantation, cardiomyoplasty, and clinical treatment of heart failure caused by idiopathic dilated cardiomyopathy. METHODS: Ninety patients with refractory heart failure caused by idiopathic dilated cardiomyopathy were observed from May 1988 to March 1993. The patients had New York Heart Association functional class III or IV symptoms. The patients were divided in three groups according to the treatment received: heart transplantation (33 patients), cardiomyoplasty (25 patients), or medical treatment (32 patients). We studied the event-free curve, the New York Heart Association functional class, the left ventricular ejection fraction, and the morbidity of the groups in the follow-up of 19 +/- 16 months. We considered as an event death or crossover to another group because of severe symptoms. RESULTS: The event-free rate in the cardiomyoplasty group was 92%, 88%, 79%, 74%, and 62% at 3, 9, 12, 18, and 24 months of follow-up, respectively. The event-free rate after heart transplantation was 82%, 78%, 82%, 75%, and 69% at 3, 9, 12, 18, and 24 months, respectively. The event-free rate in the medical treatment group was 78%, 65%, 61%, 48%, and 48% at 3, 9, 12, 18, and 24 months, respectively. All surviving patients in the heart transplantation group had functional class I symptoms. After cardiomyoplasty 90% of surviving patients had class I or II symptoms and 10% had class III symptoms. However, in the medical treatment group 27% of surviving patients had class I or II symptoms and 67% had class III or IV symptoms. In the cardiomyoplasty group left ventricular ejection fraction increased from 20% +/- 3% to 24.4% +/- 6.3% at 6 months (p < 0.05). In the heart transplantation group the left ventricular ejection fraction normalized, and the mean value of the left ventricular ejection fraction did not change in the medical treatment group. The need for endomyocardial biopsy and the incidence of rejection and infection were characteristics of the heart transplantation group. CONCLUSIONS: In properly selected patients, cardiomyoplasty and heart transplantation seem to be associated with improvement in survival and functional class at mid-term follow-up. Heart transplantation was more effective than cardiomyoplasty for functional class improvement.

Adult↗
PubMed1996

Arterial blood pressure and left ventricular hypertrophy in haemodialysis patients.

OBJECTIVE: To test the hypothesis that there is an association between arterial blood pressure and left ventricular hypertrophy and patterns of ventricular geometry, defined echocardiographically, in a group of stable haemodialysis patients with a low prevalence of extrarenal diseases. DESIGN AND METHODS: Patients with end-stage renal failure treated by regular haemodialysis (aged 44.3 +/- 12.9 years, n = 103, among whom 52 men and 23 blacks, dialysis duration 49.8 +/- 35.3 months) were subjected to echocardiographic evaluation (M-mode, bidimensional and Doppler) on the day preceding dialysis. The average of all predialysis blood pressure determinations during the 3 months preceding the tests (34-38 determinations in each patient) were used as baseline data. Univariate and multivariate tests were used to assess the main variables associated with echocardiographically defined cardiac alterations and with patterns of ventricular geometry. RESULTS: The systolic blood pressure was significantly associated with the left ventricular mass index and was significantly and independently correlated with left ventricular hypertrophy, posterior wall hypertrophy, left ventricle dilation and increased relative wall thickness. Other significant correlations were between the haematocrit level and left ventricular hypertrophy and between age and altered systolic and diastolic functions. Concentric ventricular hypertrophy was observed only in patients with a history of hypertension, whereas the prevalence of normal geometry was higher in patients without a history of hypertension. CONCLUSION: The systolic blood pressure is an important factor influencing the occurrence of left ventricular hypertrophy in haemodialysis patients and also affects the left ventricle geometry in this population.

Adult↗
PubMed1996

[Contraceptive use in women with heart disease].

PURPOSE: To analyse efficacy, tolerance and adverse events of reversible contraceptives in women with cardiac disease. METHODS: We studied prospectively during 24-39 (mean = 29) months, 89 women with heart disease with a mean age of 25.6 (16-42) years. Rheumatic heart disease was present in 73 (82%) cases, congenital heart disease in 11 (11%), coronary artery disease in 2 (2%) and cardiomyopathy in 3 (3%) case. The patients were divided in three groups: GCO--35 patients taking combined oral contraceptives (30 micrograms ethinyl estradiol and 75 micrograms gestodene--COs); GIT--27 using injectable progestagens (depot medroxyprogesterone acetate-DMPA) and GUID--27 with intrauterine device (IUD). RESULTS: In GCO occurred 4 (11.4%) cases of arterial hypertension, 1 (2.8%) of a transient cerebral isquemic attack, 3 (8.5%) of spotting, 1 (2.8%) of amnorrhea e 1 (2.8%) pregnancy. Interruption of this method occurred in 4 (11.4%) cases due to hypertension (2), pregnancy (1) and amenorrhea (1). In group GIT there were 2 (7.4%) cases of arterial hypertension, 18 (66.6%) of amenorrhea, and 3 (11.1%) of spotting. Interruption of use occurred in 5 (18.5%) due to amnorrhea (2), weight gain (2) and headache (1). In GUID there was 1 (3.7%) case of infeccion, 1 (3.7%) pregnancy and 1 (3.7%) spontaneous expulsion of IUD. Interruption of use took place in 3 (11.1%) cases due to infeccion, pregnancy and expulsion. The comparation between the groups demonstrated a difference in the incidence of amenorrhea (p < 0.005) and descontinuation of use of the method (p < 0.025). CONCLUSION: Use of reversible contraceptives in heart disease women was associated with an acceptable cardiovascular risk. Efficacy and side effects of the methods were comparable in the groups, however intolerance was more observed in GIT.

Adolescent↗
PubMed1996

[Left bundle branch block analysis by body surface mapping. Comparison with electrocardiographic and vectocardiographic findings].

PURPOSE: To compare the correlation between the departure areas (DA), negative or positive, in patients whose electrocardiogram showed left bundle branch block (LBBB) and association with left ventricular hipertrophy (LVH) and myocardial infarction (MI), to the electrocardiographic (ECG) and vectocardiographic (VCG) classic criteria. METHODS: The study was carried out with 46 patients (27 males) with LBBB. These patients had hypertension (19.5%), coronary heart disease (34.7%) and 21 patients with no heart disease (45.8%). RESULTS: The statistic analysis using the Cluster method divided the patients in two groups. Group I (22 patients) showed an average rate for the DA (-2 SD) of 1091 for QRS and of 640 for ST-T. For the DA (+2 SD), the average rate was 618 for QRS and 881 for ST-T; group II (24 patients) showed an averaged for the DA (-2 SD) of 1063 for QRS and of 225 for ST-T. For the DA (+2 SD), the averaged rate was 428 for QRS and 600 for ST-T. CONCLUSION: In general the current ECG/VCG findings, can not differentiate the presence of the association of LBBB to LVH and MI. The DA of ST-T, mainly negative was the most efficient to separate the two groups and help in the differential diagnosis.

Adult↗
PubMed1996

[Lipid profile changes during the late follow-up after heart transplantation].

PURPOSE: The aim of this study was to determine the lipid profile after heart transplantation. METHODS: We performed sequential analyses in serum (in mg/dL) of total cholesterol, HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol and triglycerides in patients who underwent orthotopic heart transplantation. These analyses were performed at one month (33 patients), six months (32), one year (26), two years (22) and three years (19) after the transplantation. RESULTS: After the heart transplantation there was a progressive elevation in the serum levels of total cholesterol (215 +/- 53 at the 1st month, 229 +/- 57 at the 6th month, 239 +/- 52 at the 1st year, 250 +/- 53 at the 2nd year and 278 +/- 63 at the 3rd year, p = 0.0006). LDL-cholesterol (137 +/- 46 at the 1st month, 152 +/- 47 at the 6th month, 156 +/- 45 at the 1st year, 164 +/- 43 at the 2nd year and 180 +/- 58 at the 3rd year, p = 0.03). VLDL-cholesterol (35 +/- 15 at the 1st month, 37 +/- 14 at the 6th month, 42 +/- 14 at the 1st year, 42 +/- 15 at the 2nd year and 45 +/- 17 at the 3rd year, p = 0.01) and triglycerides (169 +/- 75 at the 1st month, 188 +/- 75 at the 6th month, 216 +/- 70 at the 1st year, 218 +/- 89 at the 2nd year and 255 +/- 103 at the 3rd year, p = 0.001). There were no changes in HDL-cholesterol levels (44 +/- 15 at the 1st month, 41 +/- 12 at the 6th month, 40 +/- 12 at the 1st year, 44 +/- 14 at the 2nd year and 45 +/- 15 at the 3rd year, p = ns). CONCLUSION: We observed a progressive elevation in the levels of total cholesterol, LDL, VLDL and triglicerides during the 1st three years after heart transplantation.

Adult↗
PubMed1996

[Normal maximal functional capacity in patients with congestive heart failure due to Chagas' cardiomyopathy].

PURPOSE: To compare patients with heart failure due to Chagas' cardiomyopathy and maximal oxygen consumption greater than 20mL/kg-1/min-1 to normal individuals. METHODS: We studied 104 male patients with heart failure due to Chagas' cardiomyopathy, functional classe II-IV, age 18 to 65 years (40.3 +/- 9.0), and 23 normal sedentary male individuals (GI) age 17 to 51 years (35 +/- 8.7). Maximal oxygen consumption (VO2max) was obtained using a Beckman metabolic measurement cart, and left ventricular ejection fraction (EF) by conventional transthoracic echocardiography. Comparisons between means were made with t-test. RESULTS: Thirty seven patients (35.6%) presented VO2max above 20mL/kg-1/min-1 (G2), with values ranging from 20.5 to 30 (24.5 +/- 2.9) and EF between 19 and 63% (42 +/- 11.7). GI had VO2max between 21 and 42mL/kg-1/min-1 (33.3 +/- 5.6) and EF between 70 and 82% (75.1 +/- 3.2). Ages were not significantly different for the two groups (p = 0.1136). VO2max and EF were lower in G2, and this was statistically significant (p < 0.0001). CONCLUSION: These results indicate that patients with congestive heart failure due to Chagas disease may show values of VO2max, greater than 20mL/kg-1/min-1 which does not mean that they have normal maximal functional capacity.

Adolescent↗
PubMed1996

[Effects of rejection on the contractile reserve of the graft after heart transplantation].

PURPOSE: To test the hypothesis that rejection could affect the contractility and contractile reserve of left ventricle after heart transplantation. METHODS: Echocardiographic parameters and noninvasive blood pressure end-systolic pressure (ESP), heart rate (HR), end diastolic (EDV) and end-systolic (ESV) volumes, ejection fraction (EF), end-systolic stress (ESS) and the end-systolic relation (ESS/ESV) were recorded in 68 studies in 11 patients, seven days-12 months after heart transplantation. Accordingly with the endomyocardial biopsies results were divided into two groups: group A-with no rejection (53 studies), and group B-with rejection (15 studies). RESULTS: The nitroprusside infusion changed significantly and in the same way, all the parameters except the ESS/ESV ratio (A = 5.5 +/- 1.7 x B = 4.8 +/- 1.5 g/cm2/mL, p = NS); there was a decrease in ESP (A = 107 +/- 15 and B = 109 +/- 12 mmHg, p = NS), EDV (A = 68 +/- 19 and B = 81 +/- 12 mL, p = NS), ESV (A = 12 +/- 5 and B = 18 +/- 12 mL, p = NS) and ESS (A = 59 +/- 13 and B = 82 +/- 20g/cm2, p = NS); there was an increase in HR (A = 94 +/- 9 and B = 93 +/- 16bpm, p = NS) and EF (A = 83 +/- 5 and B = 79 +/- 8%, p = NS). In the dobutamine study it was observed differences for both groups, except for ESP (A = 156 +/- 26 and B = 149 +/- 26mmHg, p = NS). The increase in HR, EF and ESS/ESV ratio was greater in group A (HR-A = 117 +/- 19 and B = 102 +/- 25bpm, p < 0.05; EF-A = 91 +/- 4 and B = 78 +/- 11%, p < 0.05; ESS/ESV-A = 13.1 +/- 6 and B = 6.1 +/- 3.1 g/cm2/mL, p < 0.05). For group A it was smaller the EDV (57 +/- 18 x 94 +/- 35 mL, p < 0.05), ESV (5 +/- 3 x 24 +/- 20 mL, p < 0.05) and ESS (57 +/- 21 x 102 +/- 40 g/cm2, p < 0.05). CONCLUSION: Rejection may not induce changes in resting left ventricular contractility, however, the contractile reserve is depressed during an episode of moderate to severe rejection.

Adult↗
PubMed1996

[Acute effects of ibopamine on left ventricular mechanics and contractility in patients with idiopathic dilated cardiomyopathy].

PURPOSE: The effects of ibopamine (IBO) on left ventricular (LV) mechanics and contractility have not been described. The aim of this study was to test the hypothesis that IBO has a contractile effect at a dose of 200 mg. METHODS: Ten male patients (43 +/- 7 years) with refractory heart failure due to idiopathic dilated cardiomyopathy were studied. The patients were submitted to simultaneous echo-Doppler and hemodynamic (microtip catheter) studies, before (B) and after (20, 40 and 60 minutes) a dose of 200 mg of IBO. LV pressure/diameter and stress/strain relations were obtained. Subsequently, heart rate (HR-bpm), cardiac output (CO-L/m), end-diastolic pressure (EDP-mmHg); fractional shortening (FS-%); maximal elastance (Emax-mmHg/cm/s); end systolic (ESS-g/cm2) and end-diastolic (EDS-g/cm2) stress; chamber (Kp-mmHg/cm) and muscle (K(m)-g/cm2) stiffness, and the time of constant relaxation (Tau-ms) were analyzed. RESULTS: Results were presented as mean +/- standard deviation for conditions before and after IBO (20, 40 and 60 minutes) respectively. There was no change in HR (99 +/- 7; 100 +/- 7; 99 +/- 8; 99 +/- 10). Significant increases were observed in CO (4.13 +/- 1.28; 4.95 +/- 1.38; 5.13 +/- 1.86; 5.18 +/- 1.57), FS (13.7 +/- 2.4; 15.4 +/- 2.8; 15.9 +/- 1.8; 16.1 +/- 2.0), and Emax (14.8 +/- 3.2; 16 +/- 3.6; 17.7 +/- 4.2; 17.6 +/- 4.2). A transient (20 minutes) increase followed by a decrease (40 and 60 minutes) occurred in EDP (26.3 +/- 4.2; 30.6 +/- 6.4; 24.6 +/- 5.6; 22.3 +/- 4.6), EDS (79.7 +/- 22.8; 91.7 +/- 29.6; 79 +/- 31; 63 +/- 17.3), and Kp (27.2 +/- 12.6; 60 +/- 26.7; 27.9 +/- 11.7; 28.1 +/- 11). CONCLUSION: IBO has a beneficial effect on LV systolic and diastolic function as well as on contractility in patients with heart failure due to idiopathic dilated cardiomyopathy.

Adult↗
PubMed1996

[Risk factors in elderly patients selected by primary care physicians for hypolipemic treatment].

PURPOSE: To evaluate the influence of age on response to pravastatin treatment in patients treated by community physicians. METHODS: According to age, 873 patients were divided in three groups: group A with ages ranging from 45 to 59 years (n = 55), group B with ages from 60 to 64 years (n = 182) and group C with ages from 65 to 70 years (n = 143). After four weeks only with diet orientation, patients received 10 mg/day of pravastatin for 12 weeks. RESULTS: There was a greater prevalence of risk factors in elderly patients: hypertension (45.7%, 54.4% and 57.1% in groups A, B and C respectively p = 0.0165), diabetes mellitus (9.3%, 17.6% and 25.8% respectively in groups A, B and C p < 0.0001), and previous heart disease (23.1%, 34.3% and 34.7% in groups A, B and C respectively p < 0.001). During the period of diet orientation there was a similar total cholesterol reduction in the three groups (about 10.5%), the reduction reached 30.0% with the introduction of pravastatin for 12 weeks. Low density cholesterol level decreased during the diet period in the three groups (about 10.5%), pravastatin prescription induced further reduction (about 31.7%). The high density cholesterol level (HDL) increased significantly with pravastatin treatment (12.7%). After pravastatin treatment the increase in HDL levels was more significantly among those patients with initial low levels of HDL (< 35 mg/dL) in the three groups. CONCLUSION: In patients selected by community physicians to receive lipid lowering therapy, increased age was associated with greater prevalence of risk factors and heart disease. Regardless of age, there was a good response to pravastatin treatment, however less than half of patients had received treatment prior to the protocol.

Age Factors↗
PubMed1996

[When should we stop cardiopulmonary resuscitation in patients brought to the emergency room in cardiac arrest without pre-hospital care?].

PURPOSE: The decision of stopping cardiopulmonary resuscitation (CPR) in patients brought to emergency room in arrest remains a challenge. Such decision is even more difficult when someone is brought by bystanders, after an acute loss of consciousness without any out-of-hospital care. To evaluate the probability of survival of these patients we reviewed retrospectively charts in our institution, during a period of five years. METHODS: One hundred and one patients that fulfilled these characteristics came to our emergency in arrest. The time to arrival since symptoms started, cardiac rhythm at first electrocardiogram (EKG), age, gender, initial CPR success, late outcomes and previous diseases were obtained. Patients were divided in two groups regarding which cardiac rhythms they had at first EKG: A-patients arriving in asystole; and VF-patients arriving in ventricular fibrillation. To evaluate time to arrival, we arbitrarily choose 15 min as a reference point. RESULTS: In these 101 subjects the mean age was 62 +/- 13.7 years and 63 (62.3%) were men. Previous heart disease was documented in 74 [dilated cardiomyopathy in 22 (21.7%), coronary heart disease in 41 (40.6%), arterial hypertension in 25 (24.7%) and others in 6 (5.6%)]. In 66 episodes we were sure of the time patients spent before arrival (mean 2.5 +/- 11 min). Only in 63 subjects we had no doubts about the rhythm at entrance: VF in 37 (58.7%), A in 22 (34.9%) and an accelerated idioventricular rhythm (AIR) in four (6.3%). Time to arrival was 18.6 +/- 10.6 in VF vs 32.5 +/- 11.7 min in A (p = 0.012). Fourteen (13.8%) subjects resumed a supraventricular rhythm with systolic pressure > or = 90 mmHg after CPR and all of them were in VF (13) or AIR (one). Nine patients (8.9%) evolved in coma. Only five (4.9%) were discharged from the hospital without any neurological disturbance and their time to arrival ranged from one to 15 (9 +/- 5.8) min. CONCLUSION: Delayed arrival to the emergency room (> 15 min) associated with asystole were predictors of unsuccessful CPR, and both data are helpful in deciding when to stop CPR in subjects arriving at the emergency department with no out-of-hospital care.

Aged↗
PubMed1996

[Results of aortic stenosis surgery in patients with severe ventricular dysfunction].

PURPOSE: To study the short and long term clinical course of patients with severe aortic stenosis after surgical treatment of the valvular lesion. METHODS: Thirty survivors among 31 consecutive patients with severe left ventricular dysfunction (LVD) due to aortic stenosis (AS) were submitted to clinical and echocardiographic follow-up during a mean of 30 months after surgical treatment of the valvular lesion. Twenty five (83.3%) patients were male with a mean age of 50 years (25 to 74). Before operation the following parameters were obtained: diastolic left ventricular diameter (DLVD), shortening fraction (SF), left ventricular ejection fraction (LVEF), aortic valve area (AVA), left ventricular-aortic pressure gradient (PG) and NYHA functional class (FC). During the follow up, after the surgical procedure, FC, DLVD, LVEF and SF could be analysed and compared with previous data. RESULTS: A significant rise in SF (p = 0.001) and LVEF (p = 0.0001), as well as a decrease in DLVD (p = 0.001) were observed in the follow up. Symptoms lessened in severity in the majority of patients. Three of our patients died with progressive LVD and heart failure, after at least 36 months of follow-up. These results indicate that when operation is carried out in patients with AS and left ventricular failure, a significant improvement in left ventricular function and in symptoms takes place. Although the risk of surgical treatment is increased in this group of patients, LVD should not be considered a contraindication to the procedure. CONCLUSION: The left ventricular dysfunction is not a contraindiction for the surgical treatment of the aortic stenosis.

Adult↗
PubMed1996

[Effects of partial ventriculectomy on left ventricular mechanical properties, shape, and geometry in patients with dilated cardiomyopathy].

PURPOSE: To investigate the short-term effects of the partial ventriculectomy (resection of lateral wall associated to mitral annuloplasty) on cardiac mechanics, contractility, shape and geometry of the left ventricle (LV). METHODS: Eleven male patients with severe congestive heart failure due to dilated cardiomyopathy were studied. The mean age was 51 +/- 7 years and the functional class was III (five patients) or IV (six patients) before the surgery. Patients were evaluated before and at 17 +/- 4 days after the surgery by simultaneous LV pressure and echocardiographic data. End-diastolic pressure (EDP-mmHg), wall stress (EDS-g/cm2) and diameter (EDD-cm); endsystolic wall stress (ESS) and diameter (ESD), fractional shortening (FS-%) and maximal elastance (Emax-mmHg/ cm/s); the diastolic slope of the pressure-diameter (Kp-mmHg/cm) and stress-strain (Km-g/cm2) loops; shape (L/ EDD, adimensional, where L is the LV long axis) and geometry (Th/EDD, adimensional, where TH is the LV diastolic thickness) were obtained. RESULTS: 1) The ressected muscle fragments (diamond shape) were 10.8 +/- 1.3 cm in length and 5 +/- 0.6 cm in width; 2) all patients were discharged from hospital (15-29 days) in class I (eight cases), II (two), and III (one); 3) it was observed a decrease in EDP (24.3 +/- 7.7 x 17.5 +/- 3.2, p = 0.016); in EDD (8.0 +/- 0.7 x 7.2 +/- 0.8, p = 0.002); in EDS (57.9 +/- 26.8 x 37.4 +/- 19.2, p = 0.005); in ESS (199 +/- 46.9 x 102.8 +/- 33.1, p = 0.004); in ESD (7.1 +/- 0.7 x 5.7 +/- 0.8, p < 0.001); in Kp (22.3 +/- 15.9 x 11.5 +/- 6.9, p = 0.014); and in K(m) (467.4 +/- 212 x 214.6 +/- 87.4, p = 0.01); and, 4) it was noted an increase in FS (11.5 +/- 1.8 x 19.8 +/- 3.9, p < 0.001); in Emax (13.8 +/- 2.2 x 18.6 +/- 3.2, p < 0.001); and in L/EDD (1.32 +/- 0.1 x 1.47 +/- 0.13, p < 0.007) and Th/Dd (0.11 +/- 0.04 x 0.17 +/- 0.08, p < 0.038). CONCLUSION: The partial ventriculectomy showed multiple significant beneficial effects in these dilated myopathic hearts.

Adult↗
PubMed1995

Mechanism of adenosine-induced elevation of pulmonary capillary wedge pressure in humans.

BACKGROUND: Continuous intravenous administration of adenosine to humans often results in a paradoxical rise in pulmonary capillary wedge pressure (PCWP), whereas arterial resistance is lowered and cardiac output and heart rate increase. This is believed to be due to diastolic stiffening of the ventricle or to a negative inotropic effect. In the present study, we tested these and other mechanisms by using pressure-volume (PV) analysis and echocardiography. METHODS AND RESULTS: Fifteen patients with normal rest left ventricular function underwent cardiac catheterization and received adenosine at a rate of 140 micrograms/kg per minute IV for 6 to 10 minutes. PV relations were measured in 9 patients (without coronary artery disease) using the conductance catheter method. In 6 additional patients with coronary artery disease, echocardiograms were used to assess wall thickness and function, and aortic and coronary sinus blood, lactate, oxygen, and adenosine levels were measured. Adenosine increased PCWP by 19% (+2.6 mm Hg) in both patient groups while lowering arterial load by 30% and increasing cardiac output by 45% (all P < .001). There was no significant effect of adenosine on mean linear chamber compliance or monoexponential elastic stiffness, as the diastolic PV relation was unchanged in most patients. Diastolic wall thickness also was unaltered. Thus, the PCWP rise did not appear to be due to diastolic stiffening. Adenosine induced a rightward shift of the end-systolic PV relation (ESPVR) (+12.7 +/- 3.7 mL) without a slope change. This shift likely reflected effects of afterload reduction, as other indexes (stroke work-end-diastolic volume relation and dP/dtmax at matched preload) were either unchanged or increased. Furthermore, this modest shift in ESPVR was more than compensated for by vasodilation and tachycardia, so reduced systolic function could not explain the increase in PCWP. There also was no net lactate production to suggest ischemia. Rather than arising from direct myocardial effects, PCWP elevation was most easily explained by a change in vascular loading, as both left ventricular end-diastolic volume and right atrial pressure increased (P < .05). This suggests that adenosine induced a redistribution of blood volume toward the central thorax. CONCLUSIONS: PCWP elevation in response to adenosine primarily results from changes in vascular loading rather than from direct effects on cardiac diastolic or systolic function.

Adenosine↗
PubMed1995

Magnesium treatment of acute myocardial infarction: effects on necrosis in an occlusion/reperfusion dog model.

The effects of plasma magnesium elevation on myocardial necrosis were tested in anesthetized dogs submitted to left anterior descending coronary artery occlusion and reperfusion. Eighteen dogs were treated with magnesium sulfate soon after the coronary occlusion in order to treble the plasma concentration, while 18 others remained as controls. The treatment determined only slight reductions in the heart rate and in the arterial blood pressure, from the beginning to the end of the experiment. The percent necrosis of the ischemic myocardium was determined by staining and weighting the normal, the preserved and the necrotic areas. Necrosis was noticed in 63.7 +/- 16.8% and 44.2 +/- 20.8% of the risk area in the control and treated groups, respectively (P = 0.004). It is concluded that the treatment has protected the ischemic/reperfused myocardium reducing the final necrosis of the risk area by about 30%. This effect may be ascribed to the hemodynamic changes determined by magnesium sulfate infusion as well as to metabolic actions during ischemia and reperfusion.

Animals↗
PubMed1995

Importance of the time of onset of supraventricular tachyarrhythmias on prognosis of patients with acute myocardial infarction.

It is known that left ventricular (LV) function, severity of coronary artery disease, and the presence of ventricular arrhythmias are major determinants of prognosis in patients surviving an acute myocardial infarction (AMI). However, little is known about the relationship between the time of onset of supraventricular tachyarrhythmias (SVTs) and mortality. Therefore, this study was carried out in a 48-months period on 131 patients with AMI who presented with SVT during hospitalization. Of these, 53 patients (40.5%) had arrhythmia within < 12 h of MI, while 78 patients (59.5%) had arrhythmia between 12 h and 4 days. The arrhythmias studied were atrial fibrillation, atrial flutter, and paroxysmal supraventricular tachycardia. The patients were similar for age, gender, coronary risk factors, creatine kinase-MB peak, cardioversion and LV function. Angiographic features for patients with the < 12-h onset of arrhythmia were: 86.7% of the patients had uniarterial lesions, 8.9% had biarterial lesions, and 4.4% had triarterial lesions. Patients with the 12-h-4-day onset had 16.1%, 53.2%, and 30.6% (p < or = 0.05) of the respective lesions. Inferior wall myocardial infarction was more frequent among patients with the earlier onset (60.4%), while patients with the later onset presented more anterior wall infarctions (50.0%). Only 11.3% of the patients with the earlier onset presented with severe in-hospital congestive heart failure (Killip classes III-IV), versus 62.8% of the patients with the later onset (p < or = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗