Biomedical subjects

G Bellotti

Publications and source records attributed to G Bellotti.

At least 55 records · Page 3Linked to original sources

PubMed1996

[Evaluation of ischemic preconditioning on collateral circulation, ventricular function and clinical outcome in acute myocardial infarction].

PURPOSE: To evaluate the influence of ischemic preconditioning (IP) in collateral circulation (CC), early ventricular function and in hospital outcomes after myocardial infarction (MI). METHODS: We studied 97 patients with a 1st anterior MI within 6h of pain and isolated total proximal occlusion of the left anterior descending artery, divided in 2 groups: with (GA) or without (GB) angina before MI. Coronariography and ventriculography were performed prior to reperfusion. The left ventricular (LV) ejection fraction was measured by the area length method and anterior wall motion by the centerline method. RESULTS: There was no difference between the two groups in sex, age, CKMB level, treatment, reperfusion rate. Global LV ejection fraction and anterior wall motion were similar, respectively, 39 +/- 9% and -2.55 +/- 1.17 SD/chord for GA and 37 +/- 8% and -2.75 +/- 0.79 and -2.75 +/- 0.79 SD/chord for GB (p = ns). The incidence of visible CC to the infarct area was also similar (present in 6 GA vs 8 GB patients). However, GA patients fared significantly better during hospitalization: No GA patient presented Killip class > or = 2 compared to 8 GB patients (p = 0.007). CONCLUSION: Although collateral coronary circulation grades, global and regional LV function were similar between the two groups, the presence of angina pectoris preceding an acute myocardial infarction was associated with a better in hospital evolution, what could be partially explained by preconditioning phoenomena.

Collateral Circulation↗

PubMed1996

[Comparative study between verapamil and adenosine triphosphate in the treatment of paroxysmal supraventricular tachycardia].

PURPOSE: To evaluate the efficacy and safety of intravenous (IV) adenosine-triphosphate (ATP) and verapamil to convert acute episodes of paroxysmal supraventricular tachycardia (PSVT) to sinus rhythm. METHODS: Fifty patients with PSVT were randomized in two groups: A) 25 treated with IV bolus of ATP (10 or 20mg), and V) 25 treated with IV verapamil, up to 15mg, during 3min. We evaluated the time delay necessary to convert the arrhytmia, doses, and side-effects. Patients with acute ischemic syndromes (< 3 weeks), severe congestive heart failure, and treatment with dipyridamole or methylxanthine were excluded. RESULTS: There were no differences between the two groups regarding to age, sex, and success rate. The average time till reversal were respectively, 30s and 248s for ATP and verapamil. Ventricular ectopy and general discomfort were observed in 33% of patients receiving ATP, whereas no side-effects occurred in group V. CONCLUSION: ATP is a good option to convert rapidly PSVT to sinus rhythm and, probably, could be the first choice to treat PSVT patients with ventricular dysfunction.

Adenosine Triphosphate↗

PubMed1996

[Fungal infections in 100 patients subjected to heart transplantation].

PURPOSE: To evaluate prevalence, causes, clinical aspects, topography and deaths due to fungal infections diagnosed in a series of patients submitted to heart transplantation. METHODS: 100 consecutive patients submitted to heart transplantation were studied. Follow-up was three to 90 (mean 25.38 +/- 25.97) months. Fungal infections were diagnosed by the Centers for Disease Control criteria. RESULTS: Forty seven fungal infections were found, with three deaths caused mainly by fungal infection. The most common infection in this series was oral infection by Candida albicans, Acremonium sp, Aspergillus sp, Candida tropicalis, Histoplasma capsulatum and Pneumocystis carinii were also responsible for infections in this patient population. CONCLUSION: Fungal infections caused three deaths in this series, and were responsible for increased morbidity. The authors suggest prophylactic and therapeutic recommendations.

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

[Comparative study between inoue single balloon and double balloon in percutaneous mitral valvuloplasty. Immediate results and after 1 year follow-up].

PURPOSE: To compare early and 12 months results of mitral stenosis (MS) correction by percutaneous balloon valvuloplasty (PMBV) using Inoue's single-balloon or double balloon techniques. METHODS: We submitted 139 consecutive patients to PMBV using Inoue single-balloon (n = 56, GI) or the double balloon technique (n = 83, GII). The two groups were similar, in: age, sex, functional class (FC), echocardiographic (ECHO) score, mitral valve area (MVA), and gradient (G) or presence of regurgitation. Clinical and ECHO data were compared before (PRE), immediately after (POI) and one year following the procedure (PO12M). RESULTS: PMBV was successfully performed in 53 (95%) patients of GI and in 79 (96%) of GII. Statistical analyses showed that the groups were similar at POI but different at PO12M (p < 0.002). ECHO immediately after PMBV showed that: MVA increased from 0.99 +/- 0.23 to 2.01 +/- 0.44cm2 (p < 0.001) in GI and from 0.94 +/- 0.23 to 2.09 +/- 0.35cm2 (p < 0.001) in GII and G decreased from 11.58 +/- 5.02 to 5.16 +/- 2.23mmHg (p < 0.001) in GI and from 12.48 +/- 4.89 to 5.96 +/- 3.21mmHg (p < 0.001) in GII. After one year 36 (64%) patients in GI and 62 (74%) in GII underwent an ECHO study. A comparison between immediate and one year follow-up results showed that MVA decreased from 2.01 +/- 0.4 to 2.00 +/- 0.3cm2 (NS) in GI and from 2.09 +/- 0.3 to 1.74 +/- 0.4cm2 (p < 0.001) in GII and G decreased from 5.16 +/- 2.2 to 5.50 +/- 2.9mmHg (NS) in GI and from 5.96 +/- 3.2 to 8.61 +/- 4.8mmHg (p < 0.001) in GII. There was therefore a sustained improvement of MVA and G after one year in GI and a significant decrease in MVA and G in GII. The FC after one year was similar and satisfactory in both groups. CONCLUSION: Both techniques are equally effective in relieving MS immediately after PMBV, but after one year, despite similar FC, Inoue-balloon technique seems to be superior to maintain MVA and G.

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

Peak oxygen consumption and resting left ventricular ejection fraction changes after cardiomyoplasty at 6-month follow-up.

BACKGROUND: The effects of cardiomyoplasty on cardiopulmonary exercise test characteristics are not fully known. METHODS AND RESULTS: We determined in 19 patients who underwent cardiomyoplasty for treatment of refractory heart failure (New York Heart Association [NYHA] functional class III) before (pre) and at 6-month follow-up (post) maximum oxygen consumption (peak VO2), NYHA functional class, and resting left ventricular ejection fraction (LVEF) (MUGA). We analyzed the results according to pre peak VO2 < or > 14 mL/kg per minute and the correlation between the changes in absolute values of LVEF and peak VO2. Pre- and post-peak VO2 values were 15.9 +/- 4.4 and 18.6 +/- 6.4 mL/kg per minute, respectively (P = .059). In the subgroup with pre-peak VO2 < 14 mL/kg per minute, the peak VO2 increased from 11.1 +/- 1.9 to 16.4 +/- 6.2 mL/kg per minute (P = .02). The subgroup with peak VO2 > 14 mL/kg per minute showed pre- and post-peak VO2 of 19.2 +/- 2.6 and of 20.1 +/- 7 mL/kg per minute, respectively (P = .06). The pre-total exercise time of the entire group increased from 688.4 +/- 222.1 to 833.7 +/- 241.6 seconds (P < .04). For the subgroup with preoperative peak VO2 < 14 mL/kg per minute, exercise time improved from 585 +/- 76.9 to 825 +/- 186.3 seconds (P < .01). In the subgroup with preoperative VO2 > 14 mL/kg per minute, the preexercise and postexercise time was 763.6 +/- 264.4 and 840 +/- 282 seconds, respectively (P = .4). Pre-LVEF increased from 20.6 +/- 3.3% to 24.2 +/- 7.8% at 6 months of follow-up (P = .02). At 6 months of follow-up, 9 patients were in NYHA functional class I and 10 were in class II. There was no correlation between LVEF values and absolute values of peak VO2 before (r = .123, P = .6) and after (r = .27, P = .2) cardiomyoplasty. A weak correlation was observed between the changes in absolute values of peak VO2 and LVEF from the preoperative to the postoperative period (r = .48, P = .048). CONCLUSIONS: Cardiomyoplasty is a useful method for improving NYHA functional class and LVEF in patients with heart failure. Peak VO2 < 14 mL/kg per minute before cardiomyoplasty may be a selection criterion with which to determine improved exercise capacity after surgery. The effects of cardiomyoplasty on LVEF appear to be partially associated with maximum exercise capacity changes.

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

Autoimmunity in Chagas disease cardiopathy: biological relevance of a cardiac myosin-specific epitope crossreactive to an immunodominant Trypanosoma cruzi antigen.

Heart tissue destruction in chronic Chagas disease cardiopathy (CCC) may be caused by autoimmune recognition of heart tissue by a mononuclear cell infiltrate decades after Trypanosoma cruzi infection. Indirect evidence suggests that there is antigenic crossreactivity between T. cruzi and heart tissue. As there is evidence for immune recognition of cardiac myosin in CCC, we searched for a putative myosin-crossreactive T. cruzi antigen. T. cruzi lysate immunoblots were probed with anti-cardiac myosin heavy chain IgG antibodies (AMA) affinity-purified from CCC or asymptomatic Chagas disease patient-seropositive sera. A 140/116-kDa doublet was predominantly recognized by AMA from CCC sera. Further, recombinant T. cruzi protein B13--whose native protein is also a 140- and 116-kDa double band--was identified by crossreactive AMA. Among 28 sera tested in a dot-blot assay, AMA from 100% of CCC sera but only 14% of the asymptomatic Chagas disease sera recognized B13 protein (P = 2.3 x 10(-6)). Sequence homology to B13 protein was found at positions 8-13 and 1442-1447 of human cardiac myosin heavy chain. Competitive ELISA assays that used the correspondent myosin synthetic peptides to inhibit serum antibody binding to B13 protein identified the heart-specific AAALDK (1442-1447) sequence of human cardiac myosin heavy chain and the homologous AAAGDK B13 sequence as the respective crossreactive epitopes. The recognition of a heart-specific T. cruzi crossreactive epitope, in strong association with the presence of chronic heart lesions, suggests the involvement of crossreactivity between cardiac myosin and B13 in the pathogenesis of CCC.

Amino Acid Sequence↗

PubMed1995

The Medicine, Angioplasty or Surgery Study (MASS): a prospective, randomized trial of medical therapy, balloon angioplasty or bypass surgery for single proximal left anterior descending artery stenoses.

OBJECTIVES: This study sought to evaluate, in a prospective and randomized trial, the relative efficacies of three possible therapeutic strategies for patients with a single severe proximal stenosis of the left anterior descending coronary artery and stable angina. BACKGROUND: Although percutaneous transluminal coronary angioplasty and coronary artery bypass surgery are often performed in patients with a single proximal stenosis of the left anterior descending coronary artery, it is unclear whether revascularization offers greater clinical benefit than medical therapy alone. METHODS: At a single center, 214 patients with stable angina, normal ventricular function and a proximal stenosis of the left anterior descending coronary artery > 80% were randomly assigned to undergo mammary bypass surgery (n = 70), balloon angioplasty (n = 72) or medical therapy alone (n = 72). Angioplasty had to be considered technically feasible in every case. The predefined primary study end point was the combined incidence of cardiac death, myocardial infarction or refractory angina requiring revascularization. RESULTS: At an average follow-up period of 3 years, a primary end point had occurred in only 2 patients (3%) assigned to bypass surgery compared with 17 assigned to angioplasty (24%) and 12 assigned to medical therapy (17%) (p = 0.0002, angioplasty vs. bypass surgery; p = 0.006, bypass surgery vs. medical treatment; p = 0.28, angioplasty vs. medical treatment, all by log-rank test). There was no difference in mortality or infarction rates among the groups. However, no patient allocated to bypass surgery needed revascularization, compared with eight and seven patients assigned, respectively, to coronary angioplasty and medical treatment (p = 0.019). Both revascularization techniques resulted in greater symptomatic relief and a lower incidence of ischemia on the treadmill test; however, all three strategies eventually resulted in the abolition of limiting angina. CONCLUSIONS: The more aggressive therapeutic approach with initial bypass surgery for patients with a single severe proximal stenosis of the left anterior descending coronary artery is associated with a lower incidence of medium-term adverse events than coronary angioplasty or medical treatment. However, all three strategies resulted in a similar incidence of death and infarction during an average follow-up period of 3 years. This information should be taken into consideration when physicians and patients make therapeutic choices in this setting.

Angioplasty, Balloon, Coronary↗