Heart transplantation for chronic Chagas' heart disease

BACKGROUND

Chagas' disease has been considered a contraindication to heart transplantation as Trypanosoma cruzi infection could recur after immunosuppression.

METHODS

We report the follow-up of 22 patients who underwent orthotopic heart transplantation for treatment of end-stage chronic Chagas' heart disease, divided in two groups. Group 1 consisted of 9 patients operated on from September 1985 to June 1991, and group 2 patients underwent transplantation from July 1991 to June 1995. After our early experience with group 1, we attempted to use a lower cyclosporine dosage in group 2.

RESULTS

Total actuarial survival at 24 months was 60%, and it was better for group 2 (33% for group 1, 80% for group 2, p = 0.008). Parasitemia occurred similarly in both groups, but Chagas' disease reactivation was seen in 5 group 1 patients and in 1 group 2 member (p < 0.002). Neoplasia developed in 5 group 1 patients and 1 group 2 patient, and contributed to death in 3 of them.

CONCLUSIONS

These data demonstrate satisfactory outcome of cardiac transplantation in patients with end-stage Chagas' heart disease in the second phase of our experience. Further progress is necessary to improve the results and evaluate its proper role in the management of this disease.

[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.

Dynamic cardiomyoplasty in the treatment of dilated cardiomyopathy: current results and perspectives

BACKGROUND

The purpose of this article is to provide an overview of the current indications, results, and perspectives of dynamic cardiomyoplasty in the treatment of patients with dilated cardiomyopathy. Particular emphasis is placed on the clinical experience with 36 patients operated at the São Paulo Heart Institute between 1988 and 1995.

METHODS

Based on several clinical reports, the mechanisms of action of dynamic cardiomyoplasty in these patients include the enhancement of left ventricular systolic function, by the direct action of synchronized skeletal muscle flap contraction and the reversion of chamber remodeling. Moreover, both mechanisms seem to be responsible for improved diastolic function properties and for the decrease of ventricular wall stress. Besides the acceptable hospital mortality observed for patients with dilated cardiomyopathy ranging from 0% to 8% with this surgical procedure, clinical improvement after dynamic cardiomyoplasty has been demonstrated as a prevailing and significant outcome.

RESULTS

Nevertheless, the 1-year survival for these patients ranges from 82% to 86% and the 5-year survival on the order of 41% to 49%. In addition, the analysis of factors influencing the outcome showed that cardiomyoplasty long-term survival was significantly affected by the severity of preoperative clinical compromise and cardiac function impairment. On the other hand, patients with dilated cardiomyopathy who were operated in functional Class III or intermittent Class IV and with pulmonary vascular resistance below 4 Wood units, present survival rates on the order of 79% at 2 years and of 64% at 5 years of follow-up, which are similar to those reported after cardiac transplantation.

CONCLUSIONS

Furthermore, technological advances incorporated in the new cardiomyostimulators may ameliorate skeletal muscle flap performance at long term. Other developments are also discussed in this field.

[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.

[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.

[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.

Determinants of prognosis in 300 episodes of infective endocarditis

We studied 300 episodes of infective endocarditis in 287 patients to evaluate clinical and laboratory determinants of prognosis by estimating the probability of in-hospital death. The patients' ages ranged from 2 months to 78 (mean 30.76 +/- 16.06) years; 185 (62%) episodes occurred in male and 115 (38%) in female patients. A total of 386 complications occurred in 223 (74%) episodes of endocarditis. The infecting microorganisms were streptococci in 147 episodes, Staphylococcus aureus in 59, Staphylococcus epidermidis in 14, gram-negative bacteria in 16, other gram-positive bacteria in 8, fungi in 4. The causative microorganism was not identified in 52 episodes (negative blood cultures). The underlying cardiac disease was valvular in 119 episodes, congenital in 37, prosthetic heart valve in 69, and others in 6. No previous heart disease was identified in 69 episodes. Surgical treatment was carried out in 102 (34%) patients. Overall, 78 (26%) patients died. The probability of death was estimated with a logistic regression model (stepwise procedure). The model with best prediction included the cardiac status previous to the endocarditis, the causative microorganism, the occurrence of complications, and the blood leukocyte count. The most important variable in predicting in-hospital death was the occurrence of complications, followed by cardiac status (prosthetic valve endocarditis), the infecting microorganism, and leukocyte count. The model underestimated the severity of the disease in patients with acute endocarditis and overestimated in patients with prosthetic valve endocarditis submitted to surgical treatment.

In vivo detection of Trypanosoma cruzi antigens in hearts of patients with chronic Chagas' heart disease

The heart is the most commonly affected organ in chronic Chagas' disease, and lymphocytic myocarditis is often observed. However, the pathogenesis of chronic Chagas' heart disease is controversial. The purpose of this study was to determine whether in vivo T. cruzi antigens could be detected in hearts from patients with chronic Chagas' disease and to investigate whether a correlation between these antigens and the intensity of myocardial inflammation exists. We studied 16 patients with chronic Chagas' heart disease. Ten patients had severely impaired left ventricular function and refractory heart failure, and six had episodes of sustained ventricular tachycardia without severe left ventricular dysfunction. Eight patients underwent magnetic resonance imaging with gadolinium enhancement to guide endomyocardial and surgical biopsies to sites with more intense inflammatory processes. Myocardial specimens were studied with immunohistochemical techniques by using rabbit anti-T. cruzi immune serum to detect the presence of T. cruzi antigen. All patients had evidence of some myocarditis in at least one myocardial fragment. T. cruzi antigen was detected in 11 (69%) patients. T. cruzi antigens were detected in 10 (71%) of 14 regions with histopathologic evidence of moderate or severe myocarditis. In contrast, T. cruzi antigens were detected in 3 of 18 regions with only mild or absent myocarditis. There was a statistically significant correlation between the presence of T. cruzi antigens and moderate or severe myocarditis (chi-square = 5.169, p = 0.023). The results of this in vivo study demonstrate that T. cruzi antigens are frequently detected in chronic Chagas' heart disease. In addition, there is an association between the intensity of the inflammatory process and the presence of T. cruzi antigens. The presence of the T. cruzi antigen and its correlation with the severity of myocardial inflammatory process provide strong supportive evidence for the role of T. cruzi even in the chronic forms of Chagas' heart disease.

[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.

[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.

[Analysis of elastic retraction in the 1st 15 minutes after coronary balloon angioplasty]

PURPOSE

To determine the time course of elastic recoil (ER) in the first 15min after successful percutaneous transluminal coronary angioplasty (PTCA).

METHODS

One hundred and fifty four patients, with stable or unstable angina were successfully submitted to PTCA. Coronary angiography was undertaken shortly after balloon deflation and repeated 5, 10 and 15 min thereafter. Quantitative coronary angiography was performed with the aid of an eletronic caliper. We calculated the minimal luminal diameter (MLD) and elastic recoil in all angiograms.

RESULTS

The average artery's reference diameter was 3.09 +/- 0.61mm and the maximal balloon diameter was 2.95 +/- 0.52mm. MLD before the procedure was 0.65 +/- 0.42mm reaching 2.23 +/- 0.55mm immediately after dilatation (p < 0.0001), and decreasing to 2.09 +/- 0.47mm at 5min (p < 0.0001), 2.01 +/- 0.47 at 10min (p < 0.0001) and to 1.91 +/- 0.56mm at 15min (p < 0.0001). ER increased during the 1st 15min after PTCA, averaging 34.29 +/- 20.40%. In the group of patients whose balloon/artery relationship was < or = 1, the total ER was 0.90 +/- 0.74mm at 15min and 1.20 +/- 0.50mm when the ratio was > 1 (p < 0.0001). We noted that ER in the group of patients with residual stenosis ranging from 30 to 50% at the immediate angiogram after PTCA was greater than in the group whose residual stenosis was less than 30%.

CONCLUSION

ER is a dynamic and progressive phenomenon taking place within the 1st 15 min after a successful PTCA. Total ER was 34.29 +/- 20.40% at 15min and was greater when balloon/artery relationship was > 1. Residual stenosis ranging from 30 to 50% in the control immediately after the procedure is a predictive factor of greater ER in the 15min following PTCA.

[Infective endocarditis in 100 patients subjected to heart transplantation]

PURPOSE

An analysis of occurence, etiology, clinical aspects and death rate of infectious endocarditis cases involving patients who underwent heart transplantation.

METHODS

100 consecutive heart transplant patients were analysed; follow-up varied from three to 90 (medium of 25.38, SD +/- 27.97) months. Diagnostic criteria for endocarditis were those of the epidemiology and quality control service, Heart Institute, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, that agree with those of the Center for Disease Control. Diagnosis was established mostly by blood cultures, echocardiograms, either transthoracic or esophageal and autopsy.

RESULTS

Six cases of endocarditis were recognized, with four deaths; in three of those we found severe systemic compromise. All cases had fever as an important symptom.

CONCLUSION

Death risk seems high of infectious endocarditis after heart transplantation. The cause of this high risk appears to be linked to the bacteria themselves, to association with other clinical situations and to the use of immunosuppresive agents. We recommend a high index of suspition when risk factors are present in order to make a rapid diagnosis soon enough in the natural history of the disease; treatment has to be started as soon as possible.

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.

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.

[Magnetic resonance imaging in chronic Chagas cardiopathy. Correlation with endomyocardial biopsy findings]

PURPOSE

To study the correlation between magnetic resonance imaging of the heart and right ventricle endomyocardial biopsy results in chronic Chagas' heart disease.

METHODS

Ten patients with Chagas' disease, mean age 47 +/- 7 years, all males, in congestive heart failure with New York Heart Association class II (2 patients), III (6) and IV (2) were studied. Mean left ventricular ejection fraction was at echocardiogram 36 +/- 6%. The patients were submitted to right ventricular endomyocardial biopsy and magnetic resonance imaging of the heart. The results of this group were compared with a control group of patients with idiopathic dilated cardiomyopathy, with mean age of 46 +/- 10 years and left ventricular ejection fraction of 30 +/- 4%, in heart failure with functional class II (1 patient), III (5) and IV (1).

RESULTS

All patients with Chagas' heart disease presented an increase in magnetic ressonance imaging signal of the heart after gadolinium use. The septal signal intensity changed from 0.87 +/- 0.06 to 1.54 +/- 0.16 (p < 0.001). In the control group the mean septal signal intensity was 0.93 +/- 0.07 before and 0.89 +/- 0.06 after the gadolinium (p = ns). Eight patients of the Chagas' disease group had biopsy proven myocarditis and two had borderline myocarditis. However, only one patient of the control group had diagnosis of borderline myocarditis.

CONCLUSION

Myocarditis is frequently found in Chagas' heart disease patients and who unlike controls present a significant increase in myocardial signal intensity after gadolinium infusion. The magnetic resonance imaging of the heart seems a promising alternative method for the diagnosis of an inflammatory process in Chagas' heart disease.

[Evaluation of chronic morphological changes in the latissimus dorsi, after cardiomyoplasty, with magnetic resonance]

PURPOSE

Long term clinical and hemodynamic benefits of dynamic cardiomyoplasty (DC) have been reported. However, no information is available about long-term morphological changes in the wrapped latissimus dorsi (LD) muscle in humans.

METHODS

The latissimus dorsi muscle flap was evaluated by magnetic resonance imaging (MRI) in 5 patients submitted to DC for treatment of severe dilated cardiomyopathy. All patients were studied from 24 to 52 months after the surgical procedure at the time of the cardiomyostimulator replacement. In the interim, LD was stimulated with burst of 6 pulses (burst duration 185 msec, burst freq 30Hz) synchronized to every cardiac contraction with a maximum of 100 LD contractions/min. Images were acquired on a GE Sigma 1.5 T system (TE = 25ms, TR = R- Rx2, slice thickness 8mm).

RESULTS

The thickness of was 7.6 +/- 0.8mm. In addition, the signal intensity of the LD was compared with that of thoracic skeletal muscle and was found to be increased (2.19 +/- 0.42). The signal intensity was similar to that of subcutaneous fat in those images.

CONCLUSION

Morphologic changes in the wrapped LD muscle consistent with fatty degeneration occur after DC and can be detected by MRI. Further studies will be necessary to demonstrate the clinical significance of such LD muscle flap changes.

[Postoperative course of left ventricular function in aortic insufficiency]

PURPOSE

To analyze the follow-up of left ventricular function (LVF) after surgical correction of severe chronic aortic insufficiency (AI).

METHODS

Twenty-one out of 68 patients with AI, initially asymptomatic and that developed symptoms during the follow-up period of 24-36 months, were studied. Relationship between symptoms and LVF by echocardiogram and radioisotopic ventriculography at rest and in isotonic exercise were studied. Three clinical moments (CM) were assumed: CM-0- at the beginning of the study, when all patients were asymptomatic; CM-1- manifestation of the symptoms during 24-36 months; CM-2- corresponding to the late post-operative period of 8 months of 20 out of 21 patients (one refused the surgery). The analysis did not show any significant differences between the mean values of all echocardiographic variables (diastolic and systolic diameters, shortening fraction, final systolic stress, volume-mass ratio, contractility index) and the ejection fraction of the left ventricle (EF) obtained by the radioisotope ventriculography at rest and, including exercise, between clinical moments 0 and 1.

RESULTS

In the CM-2, involution was verified for functional class I/II in all cases and absence of expressive complications or immediate or late postoperative mortality. Comparison between CM-2 and 0 showed expressive regression of the diameters at rest in the postoperative period and with significant improvement in the means mainly the percentual variation of the EF and total time of effort.

CONCLUSION

Symptoms assembled patients with more advanced eccentric hypertrophy and did not coincide with any immediate change in findings studied at rest and at exercise. It represented a point of reference for surgical indication compatible with late postoperative involution of chronic adaptation of AI.

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.

[Infections in 100 heart transplantation patients]

PURPOSE

A prospective study of infective agents in diagnosed infections and deaths by specific agents in cardiac transplant patients.

METHODS

Infections occurring in a series of 100 consecutive cardiac transplant patients after transplantation with definite infectious diagnosis were studied; follow-up after transplantation was 3 to 90 (medium 25.38 +/- 25.97) months. Diagnostic criteria for defining infections were those used in the Epidemiology and Quality Control Division of the INCOR, that are the same published by the Centers for Disease Control. The following parameters were analysed: infections/patient/time, causes of infection and organs infected, clinical presentation and clinical aspects of infections, methods used for the infective diagnosis and relationship between rejection episodes and infection. Death caused by infections and survival rates per infection were also studied.

RESULTS

Bacterial infections were more frequent (56.3% of all infections), followed by viral infections (19.6%), fungal infections (18%) and protozoal infections (6.1%). Of all deaths after transplantation, 25% were caused by infections.

CONCLUSION

Infections are an important cause of mortality and morbidity in this patient population; our data are in accordance to the other reported series.

[Clinico-morphological dissociation in patients with mitral valve stenosis]

PURPOSE

To study characteristics of the natural history of mitral stenosis (MS) in patients that have no correlation between mitral valve areas (MVA) and symptoms.

METHODS

We studied 18 patients with MS, that presented no correlation between MVA and functional class (FC), 16 (89%) were female and two (11%) men, with age ranging from 16 to 54 (mean 33) years. Patients assigned to group A (8 cases) had FC III and MVA > or = 1.5 cm2 and group B (10 cases) FC I/II and MVA < 1.1 cm2. FC and MVA at the start (initial time-It) and after 12 months or before surgical correction (SC) or percutaneous mitral balloon valvuloplasty (PBV) (final time-Ft) were compared. All patients with predict O2 uptake (%PRED VO2) at It were evaluated.

RESULTS

Five (63%) patients of group A, that maintained MVA > or = 1.5 cm2, changed to FC I/II but three (38%) needed a SC or PBV (2 with lesser MVA at Ft). At group B, six (60%) patients needed SC or PBV.

CONCLUSION

MS patients with MVA > or = 1.5 and FC III, providing MVA do not decrease, improves their FC, becoming it more compatible with MVA %PRED VO2. The cases of group B presented the greatest probability of needing SC or PVB.

[Hospital outcome of patients with right ventricular infarction and the importance of right coronary artery patency]

PURPOSE

To evaluate the importance of the right coronary artery (RCA) patency in patients with right ventricular infarction.

METHODS

Fifty-two patients with inferior wall myocardial infarction and right ventricular involvement were studied and divided in two groups: group A (GA) included 35 patients in whom the RCA was patent at coronary angiography, and group B (GB), 17 who had an occluded RCA. They were prospectively evaluated for electrical and hemodynamic complications, as well as in-hospital mortality.

RESULTS

The mortality in GA was 11% and 29% in GB, p = 0.13; electrical complications were 11% in GA and 35% in GB, p = 0.06; hemodynamic complications were 8% in GA and 41% in GB, p = 0.009.

CONCLUSION

These findings suggest a trend towards reduction in mortality and electrical complications, and significant reduction of hemodynamic complications in patients with inferior wall myocardial infarction with involvement of the right ventricle who have the RCA patent. Thus, RCA patency appears to be important in determining in-hospital outcomes of these patients.

[Preoperative erythrocytopheresis in a patient with SC hemoglobinopathy and mitral stenosis]

Hemoglobinopathies are associated with thrombotic complications, when exposed to cardiopulmonary bypass. A 54-year old, black woman with hemoglobinopathy SC and severe mitral stenosis was submitted to eritrocytopheresis 48 hours before mitral commissurotomy surgery. The therapeutic determined appearance of the percentual hemoglobin A of 68% with reduction the hemoglobin S of 48% to 15% and the hemoglobin C of 51% to 17%. No complications occurred during postoperative period. To best of our knowledge, that is the first report about application the eritrocytopheresis in the pre operative extra corporeal circulation care in surgical treatment of patients with chronic rheumatic heart disease and hemoglobinopathy SC.

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.

Lipoprotein (a) in subjects with or without coronary artery disease: relation to clinical history and risk factors

Lipoprotein (a) [Lp(a)] is an atherogenic lipoprotein resembling low-density lipoprotein (LDL) but with an additional apoprotein (apo), apo(a). To determine whether plasma Lp(a) levels can influence the clinical presentation and extent of coronary artery disease (CAD), Lp(a), plasma lipids and apolipoproteins were determined in 203 Caucasian subjects with CAD and in 66 subjects without CAD, all confirmed by cinecoronariography. CAD patients were divided into groups according to their clinical history. The extent of the disease was evaluated by a scoring system. Lp(a) was elevated in CAD patients compared to subjects without CAD. However, there was no difference between patients that had myocardial infarction as the first manifestation of the disease and those who had only angina pectoris for at least two years. Plasma Lp(a) levels were correlated with extent of the disease. Among patients with CAD, Lp(a) was higher in females. Lp(a) was also studied separately in 29 Black subjects, 12 without CAD and 17 with CAD. In Black subjects, Lp(a) was higher than in Caucasians but there was no difference between subjects with and without CAD. Among the other risk factors studied, only plasma apo B levels and smoking were correlated with CAD.

Maternal and fetal outcome in pregnant women with Eisenmenger's syndrome

Interruption of pregnancy is usually recommended for pregnant women with Eisenmenger's syndrome. We studied 13 pregnancies in 12 women with this syndrome, who decided to carry on with their pregnancy despite recommendation for therapeutic abortion. The mean age was 27 years. Five patients had ventricular septal defect; two, persistent ductus arteriosus; one, a combination of both; two, atrial septal defect; one, atrioventricular septal defect and one patient a combination of ventricular and atrial septal defects. Mean systolic and diastolic arterial pulmonary pressures were 112.7 and 61.7, mmHg, respectively. There were three spontaneous abortions, one premature labour at 23 weeks of gestation and two maternal deaths during the 23 and 27 weeks of gestation. Seven patients who reached the end of the second trimester were hospitalized until delivery and received heparin (20,000 to 40,000 units per day) and oxygen therapy. Caesarean section was performed in all patients as a result of worsening maternal or fetal clinical condition during the third trimester of gestation. all the mothers were discharged from hospital but one of them died on the 30th day post-partum. Five of the eight infants were premature, three were small babies for gestational age and all were discharged from hospital with the exception of one who died 48 h after birth. In conclusion, although pregnancy should be discouraged in women with Eisenmenger's syndrome, it can be successful. In this study, prolonged bed rest, the use of heparin and oxygen therapy presumably positively influenced maternal and infant outcomes.

[The relationship between left ventricular function and the precipitation of symptoms in severe chronic aortic insufficiency]

PURPOSE

To study the relationship between symptoms and left ventricular function in 68 patients with severe chronic aortic regurgitation using echocardiogram and radionuclide left ventriculography at rest.

METHODS

Three stages of natural history are assumed: the 1st, at the beginning of the study, when all patients were asymptomatic (clinical stage 0); the 2nd, at the end of 36 month persistence of asymptomatic (clinical stage 1), consisting of 45 patients (group AA); the 3rd, on occasion of manifestation of the symptoms during this period of time (clinical stage 2), consisting of 21 patients (group AS-PRE), with two fatalities not related to valvopathy.

RESULTS

The comparison between the groups resulted in similarities in the mean ages, mean time of knowledge of the disease, predominance of males and rheumatic etiology. The profile analysis showed that the significant initial differences between the average of all echocardiographic variables (diastolic diameter, systolic diameter, shortening fraction, final systolic stress, volume-mass ratio, contractility index) and of the ejection fraction of the left ventricle obtained by the radionuclide ventriculography at rest, remained during the study.

CONCLUSION

Development of symptoms grouped patients with more advanced excentric hypertrophy, did not coincide with any immediate change in the laboratory markers studied at rest and it was used as a referential for surgical therapy.

Present trends in clinical experience with dynamic cardiomyoplasty

Dynamic cardiomyoplasty has been performed to reinforce the myocardium in the treatment of patients with severe cardiomyopathies. At the Heart Institute of São Paulo University Medical School, 36 patients were submitted to cardiomyoplasty between May 1988 and December 1993. The indications were idiopathic dilated cardiomyopathy in 31, ischemic cardiomyopathy in 3, and Chagas' disease cardiomyopathy in 2 patients. Twenty-eight patients were categorized in New York Heart Association (NYHA) Class III and 8 in Class IV despite the use of maximal medical therapy. There were no hospital deaths, and patients were followed up from 2 to 70 months (mean, 24 months). Besides the improvement of NYHA functional class from 3.2 +/- 0.6 to 1.6 +/- 0.9 at 6 months of follow-up, patients also presented significant changes in the left ventricular systolic and diastolic functions. Nevertheless, 16 patients died, and 2 patients were submitted to heart transplantation during late follow-up. Actuarial survival rates were 82.3% at 1 year, 61.5% at 2 years, and 38.8% at 5 years of follow-up. Otherwise, the analysis of factors influencing the outcome showed that long-term survival was significantly affected by preoperative functional class and by pulmonary vascular resistance. The 26 patients operated in NYHA functional Class III and with pulmonary vascular resistance below 4 Wood units presented survival rates of 72.7% at 2 years and of 63% at 5 years of follow-up. In conclusion dynamic cardiomyoplasty improves functional class and left ventricular function in patients with severe cardiomyopathies. However, the long-term survival after this surgical procedure may be limited by the patients' condition before the operation.

[Significance of the nuclear magnetic resonance in the detection of coronary artery patency after thrombolysis]

PURPOSE

To determine the value of magnetic resonance imaging (MRI) in the noninvasive detection of infarct related coronary artery patency after thrombolysis.

METHODS

We studied 26 patients with acute myocardial infarction submitted to thrombolysis underwent MRI studies before and after 0.1mmol/kg gadolinium-DTPA injection within the first 48 h of MI. Signal intensity was assessed by circumferential profile analysis techniques.

RESULTS

The average ratio of signal intensity of infarcted tissue over normal myocardium (I/N) was significantly higher in patients with patent arteries (1.3 +/- 0.13 vs 1.12 +/- 0.07, p < 0.02). Compared to coronariography MRI, sensitivity of 81% and specificity of 100% for the diagnosis of coronary patency.

CONCLUSION

Gadolinium infusion increased infarcted and normal myocardium differentiation. The study of gadolinium kinetics at MRI is a promising technique for noninvasive diagnosis of coronary patency.

[Mitral stenosis correction by double catheter-balloon valvuloplasty technique]

PURPOSE

To evaluate long-term efficacy of double balloon percutaneous mitral valvuloplasty technique (PMV2B).

METHODS

Sixty-eight patients (76% female), mean-age 32 (15-69) years who had been submitted to PMV2B, that completed clinical and echodopplercardiographic one year follow-up (PO12M). Admission criteria were: exertional dyspnoea, no thromboembolism antecedent up to three months before the procedure, absence of other cardiac disease requiring correction, an admissible echodopplercardiographic score, absence of intracavitary thrombus and mitral regurgitation absent or minor.

RESULTS

The patients were divided in two groups: group A of 7 (11%) patients that have a cardiac event in this period, and group B of 61 patients that completed the follow-up without a cardiac event. In group A three patients have had a severe mitral regurgitation, one case was unsuccessful and other one had a re-stenosis. There were two deaths, not related to the intervention. In group B, haemodynamic results before and immediately after PMV2B (POI) showed a significant improvement, except in relation to cardiac index. There was an increase in the grade of mitral regurgitation in 17 (28%) patients and in two cases this regurgitation became moderate. The mitral valvar area (MVA) variation between PRE x POI x PO12M presented, comparing MVA between POI and PO12M, a significant reduction. Two (3%) patients with a reduction greater than 50% of the initial increase, 33 (54%) between 10 and 50% and 26 (42%) less that 10% remained in functional class I/II.

CONCLUSION

PMV2B is an attractive treatment to select symptomatic mitral stenosis patients, with a low incidence of complications, symptomatic effective improvement that was maintained in one year follow-up, although there was a reduction in MVA.

[Acute atrial fibrillation in the emergency room. Which is the best drug for a rapid sinus rhythm conversion?]

PURPOSE

To evaluate differences between amiodarone, procainamide and quinidine in the time delay necessary to convert acute atrial fibrillation (AF) to sinus rhythm.

METHODS

Sixty patients with acute AF were randomized in three groups (G) and treated with: quinidine (QG)-(21 patients) i.v. digital + quinidine up to 600 mg; procainamide (PG)-(23 patients) i.v. digital + i.v. procainamide, 10 mg/kg; amiodarone (AG)-(16 patients) i.v. amiodarone, 5 mg/kg. To evaluate time delay to conversion, all patients have their rhythm recorded by Holter system during four hours. Statistics were done with x2, considering significant a p < 0.05.

RESULTS

There were no differences between groups regarding to age, gender and delay from symptoms initiation and medical assistance. Conversion to sinus rhythm occurred, in QG-71.4% cases; PG-47.8% and AG-50% (p > 0.05). Time delay in minutes to conversion were, respectively (media +/- SD): QG-112 +/- 43; PG-44.1 +/- 28; AG-20 +/- 13, significantly lower in PG and AG related to QG (p = 0.001). Although not significant, side effects were observed mostly in PG.

CONCLUSION

Amiodarone is a good choice to convert, very quickly, acute AF. Otherwise, quinidine has the best rate of conversion but with a longer time delay.

Survival and predictors of survival in patients with congestive heart failure due to Chagas' cardiomyopathy

BACKGROUND

The fundamental determinant of the natural history of Chagas' disease is cardiac involvement.

METHODS AND RESULTS

We studied 104 male patients with congestive heart failure due to Chagas' disease to estimate the survival distribution function and to evaluate age, functional class (FC), maximal oxygen consumption (VO2max), and ejection fraction (EF) as predictors of survival. Statistical evaluation was performed through univariate (Student's t test and chi 2 test) and multivariate analyses (Cox's regression model). Overall survival was 66% at 1 year, 56% at 3 years, and 48% at 5 years. Ages were not statistically different (P = .9811) between survivor (40.3 +/- 8.7) and nonsurvivor (40.3 +/- 9.4) groups. The ejection fraction(s) were statistically different (P = .0001) between survival (43.6 +/- 9.9) and nonsurvival (30.6 +/- 8.1) groups, as was VO2max (P = .0001) (21.0 +/- 4.7 and 15.0 +/- 4.9, respectively). Most of the surviving patients were in FC II and most of the nonsurvivors were in FC IV (P = .0001). VO2max (P = .0001) and EF (P = .0008) are highly associated with survival time in the multivariate analysis, but FC (P = .0578) is less important. Age (P = .9811) did not influence survival.

CONCLUSIONS

We conclude that 50% of the patients with heart failure due to Chagas' disease die in 47 months and that VO2max and EF are important indices of survival in this group.

[Chronic rheumatic cardiopathy in a patient with of hemophilia successfully treated with surgery]

A 52 year-old man, with rheumatic cardiopathy and hemophilia was admitted to the hospital for aortic valve replacement and mitral valve commisurotomy. He had a history of allergic reaction to cryoprecipitate, and to undergo to the cardiac surgery, the ideal level of factor VIII was estimated to be 100%. To reach this level he first received 2,500UI of the factor VIII:C increasing the factor VIII:C level from 20 to 58%. During the surgery he received an additional dose of 1,500UI of factor VIII plus 3,500,000UI of aprotinin (Trasylol), which was started at the beginning of the anaesthesia and maintained during the surgical procedure, increasing the factor VIII level to 220%. The patient was discharged 11 days after the surgery without any hemorrhagic complication.

[Comparative study between ibopamine and captopril in mild and moderate heart failure. A double-blind study]

PURPOSE

To evaluate the effect on symptoms, exercise capacity (stress test) and myocardial response (Echo, and Holter) of ibopamine or captopril in patients with congestive heart failure.

METHODS

Double-blind, parallel randomized study of 18 patients, 9 in each group, studied during three months at the outpatient clinic. Twelve were male, 6 female, all in heart failure functional class II or III. The age ranged from 27 to 67 year-old (mean 48.7 years). The patients received captopril 50 mg tid or ibopamine 100 mg tid.

RESULTS

The patients presented clinical improvement in both groups. At the stress test there was an increase of exercise time from 9 to 17 minutes and from 12 to 16 minutes with captopril and ibopamine respectively. The Echo study showed respectively to captopril and ibopamine groups a left ventricular and diastolic diameter increase from 72 to 74 and from 74 to 75mm and a increase from 0.35 to 0.38 and from 0.35 to 0.39 of the left ventricular ejection fraction. The incidence of ventricular arrhythmias was similar in both groups.

CONCLUSION

These data show that ibopamine improved cardiac function, increasing the cardiac output, ejection fraction and exercise time and did not increase the incidence of arrhythmias. This effect is similar to that observed with captopril.

[Transesophageal echocardiography in the study of vascular anastomosis in a patient with right lung transplantation]

A 46 years-old man was submitted to right orthotopic lung transplantation due to pulmonary emphysema. The transesophageal echocardiography was important in the evaluation of functional and morphological aspects of pulmonary vessels after this proceeding.

Arrhythmias and sudden death after dynamic cardiomyoplasty

BACKGROUND

The main causes of death in patients with severe cardiomyopathy are progressive heart failure and sudden death. The influence of cardiomyoplasty on the incidence of sudden death and arrhythmias in patients with cardiomyopathy remains unclear. The aim of this study was to investigate the occurrence of arrhythmias and sudden death after cardiomyoplasty.

METHODS AND RESULTS

We studied 32 patients (26 male, 6 female; mean age, 48 +/- 12 years) who submitted to cardiomyoplasty for treatment of heart failure in New York Heart Association (NYHA) class III (n = 24) or class IV (n = 8). The etiology was idiopathic dilated cardiomyopathy in 27 patients, ischemic heart disease in 3 patients, and Chagas' heart disease in 2 patients. Patients were routinely studied before and every 6 months after cardiomyoplasty by means of radioisotopic angiography and 24-hour Holter monitor recordings. There were no operative or immediate postoperative deaths. During the postoperative period, 5 patients presented with acute atrial fibrillation and 1 had an episode of sustained ventricular tachycardia. All episodes were successfully treated with intravenous antiarrhythmic drugs or cardioversion. During follow-up (from 2 to 66 months), 15 patients died from sudden death (n = 5) or progressive heart failure (n = 10). Survival rates at 1, 2, and 4 years were 79.9 +/- 7%, 62.5 +/- 9.7% and 35 +/- 12.1%, respectively. At 6-month follow-up, NYHA functional class improved from 3.2 +/- 0.4 to 1.7 +/- 0.6 (P = .001) and left ventricular ejection fraction increased from 19.8 +/- 3.3% to 24 +/- 8.2% (P = .004). The mean values per day of premature ventricular complexes (PVCs) and episodes of nonsustained ventricular tachycardia (NSVT) did not change statistically. The mean number of PVCs per 24 hours before and at 6, 12, 24, 36, and 48 months after surgery were 126 +/- 44, 96 +/- 33, 90 +/- 29, 81 +/- 35, 71 +/- 35, and 59 +/- 48. The mean number of episodes of NSVT per 24 hours before and at 6, 12, 24, 36, and 48 months after surgery were 3.3 +/- 1.3, 1.9 +/- 0.5, 1.3 +/- 0.5, 1 +/- 0.5, 1.5 +/- 1.1, and 0.6 +/- 0.5, respectively. With respect to analysis of the idiopathic dilated cardiomyopathy subgroup, there also were no significant differences in the incidences of pre- and postoperative arrhythmias.

CONCLUSIONS

Despite NYHA functional class and left ventricular function improvements observed after cardiomyoplasty, the incidence of arrhythmias did not change, and sudden death was an important finding mainly in late follow-up. The problem of sudden death after cardiomyoplasty, the mechanism that produces it, and the means to prevent it remain critical areas for future research.

Magnetic resonance imaging evaluation of chronic changes in latissimus dorsi cardiomyoplasty

BACKGROUND

Long-term clinical and hemodynamic benefits of dynamic cardiomyoplasty (DC) have been reported. However, no information is available about long-term morphological changes in the wrapped latissimus dorsi (LD) muscle in humans.

METHODS AND RESULTS

The LD muscle flap was evaluated by magnetic resonance imaging (MRI) in 13 patients submitted to dynamic cardiomyoplasty for treatment of severe dilated cardiomyopathy. Eight patients were studied 15 days after the surgery (group 1) and 5 patients were studied from 24 to 52 months after the surgical procedure at the time of the cardiomyostimulator replacement (group 2). In the interim, LD was stimulated with burst of 6 pulses (duration, 185 milliseconds; burst frequency, 30 Hz) synchronized to every cardiac contraction, with a maximum of 100 LD contractions per minute. Images were acquired on a GE Sigma 1.5-T system (echo time, 25 milliseconds; repetition time, R-R x 2; slice thickness, 8 mm). The thickness of the LD decreased from 19.6 +/- 7.3 mm for group 1 to 7.6 +/- 0.8 mm for group 2 (P < .01). In addition, the signal intensity of the LD was compared with that of thoracic skeletal muscle and was found to be significantly increased in group 2 (2.19 +/- 0.42) compared with group 1 (1.04 +/- 0.07, P < .001). The signal intensity for group 2 on the T1-weighted images was similar to that of subcutaneous fat in those images.

CONCLUSIONS

Morphological changes in the wrapped LD muscle consistent with fatty degeneration occur after DC and can be detected by MRI. Further studies will be necessary to demonstrate the clinical significance of such LD muscle flap changes.

Clinical and hormonal effects of the 5 alpha-reductase inhibitor finasteride in idiopathic hirsutism

Hyperactivity of 5 alpha-reductase in the skin is considered a major mechanism of excessive hair growth in hirsute women with normal levels of serum androgens (idiopathic hirsutism). Preventing the conversion of testosterone to dihydrotestosterone by inhibiting 5 alpha-reductase activity could thus be the most rational and effective treatment in this condition. The present study evaluated the effects of the oral administration of finasteride (5 mg once daily) for 6 months in 17 young women with idiopathic hirsutism, 5 of whom were also given an oral contraceptive. The degree of hirsutism (graded by a modified Ferriman-Gallwey score), serum sex hormone levels, and serum and urinary 5 alpha-metabolism steroid profiles were determined basally and periodically during the treatment period. The modified Ferriman-Gallwey score showed a remarkable reduction after 6 months of finasteride treatment (5.9 +/- 0.6 vs. 11.7 +/- 1.3; P < 0.01). Serum 5 alpha-dihydrotestosterone and 3 alpha-androstanediol glucuronide levels were decreased, and urinary C19 and C21 5 beta/5 alpha metabolite ratios were increased compared with pretreatment values. No significant adverse effect was reported. In women treated with finasteride and oral contraceptive, clinical efficacy was slightly more pronounced. In conclusion, the 5 alpha-reductase inhibitor finasteride is well tolerated and seems to be a useful tool in the treatment of idiopathic hirsutism.

[Aneurysms of the left and non coronary sinus of Valsalva associated to mitral and aortic rheumatic valves and obstructive coronary disease]

A 30 years old, male, patient with rare multiple aneurysms of sinus of Valsalva associated to mitral and aortic regurgitation and total occlusion of circumflex artery had the clinical diagnosis made accidentally. The multiple aneurysms were detected by transesophageal echodopplercardiography and hemodynamic study. The diagnosis were confirmed at surgery and the patient underwent correction of the aneurysms through the use of pericardial patches and mitral and aortic valve replacement.

[Radiofrequency catheter ablation of type I atrial flutter]

PURPOSE

To verify the efficacy and safety of the creation of a barrier with radiofrequency (RF) in the tricuspid annulus and the vena cava ostium (TA-IVC).

METHODS

Nine consecutive patients, 7 males, with age ranging from 36 to 76 years, with paroxysmal (7 patients) or permanent (2) type I atrial flutter (negative P wave in lead II, III and F) were submitted to RF ablation of TA-IVC istmo. One deflectable catheter with 4mm size tip was introduced into the right ventricle apex and pulled back to the inferior vena cava. When the atrial electrogram was detected the RF application was started. The RF was applied (20 watts during 60s) up to the proximity of inferior vena cava ostium. The end point was to stop atrial flutter. Then a vigorous atrial stimulation protocol, including isoproterenol infusion was used. In the next day, patients were submitted to transesophageal stimulation with the same protocol.

RESULTS

Atrial flutter was interrupted in all patients (100%) with 4 to 28 (mean 16.7 +/- 7.7) applications. Eight patients (88.8%) with one session and 1 (11.1%) with two sessions. The mean time spent to stop the atrial flutter with one application was 30.5 +/- 18.5s. There were no complications. After a mean follow up of 3 +/- 1.6 month all patients (100%) are asymptomatic. Two of them are taking propranolol to control symptomatic atrial and ventricular ectopic beats.

CONCLUSION

RF ablation of the TA-IVC istmo is efficient and safe in a short term follow up to interrupt and prevent re-induction and recurrence of type I atrial flutter.

[Acquired ventricular septal defect during infective endocarditis]

We studied five patients with acquired ventricular septal defect during the course of an infective endocarditis. All patients were male and had a previous aortic valve disease associated with an aortic ring abscess. Clinical examination was useful for the diagnosis of 4 cases, emphasizing the following findings: systolic murmur and/or left paraesternal thrill and right-heart failure. Incidence of congestive heart failure was 60%, while 40% of all patients died during the in-hospital course. No specific etiologic agent was detected. Therefore, acquired ventricular septal defect should be suspected in patients with infective endocarditis of the aortic valve that evolve with a systolic murmur and/or paraesternal thrill and right-heart failure. Immediate surgical treatment is mandatory in these cases.

[The pseudo-pacemaker syndrome]

We describe three cases of the pseudo-pacemaker syndrome. One of them due to selective fast pathway fulguration of atrioventricular nodal reentrant tachycardia and two others have occurred in spontaneous form. All cases were related with the presence of first-degree atrioventricular block and sinus node tachycardia. The treatment was done with complete atrioventricular block induction catheter ablation and permanent pacemaker implantation in two patients. In conclusion, the procedure of radiofrequency ablation to control AV nodal reentry tachycardia must preserve the fast nodal pathway in order to avoid the pseudo-pacemaker syndrome and this syndrome can spontaneously occur and must be considered during investigation of etiology of syncope.

[The role of hypertrophy and left ventricular function on the occurrence of ventricular arrhythmias in arterial hypertension]

PURPOSE

To evaluate the role of left ventricular hypertrophy (LVH), left ventricular systolic function an other clinical parameters on prevalence and complexity of ventricular arrhythmias in hypertension.

METHODS

Ventricular arrhythmias were studied in 39 hypertensives by 24 hours ambulatory electrocardiographic monitoring. Frequency and complexity of ventricular arrhythmias were compared among 3 groups: A and B, respectively without and with LVH, both with normal left ventricular function; and C with LVH and systolic dysfunction. LVH and systolic dysfunction were established echocardiographically. Linear regression analysis was performed in order to identify an independent correlation between clinical parameters and presence of arrhythmias.

RESULTS

Group C patients were older and had significantly higher systolic and diastolic blood pressures, greater mass index, diastolic posterior wall thickness and end-systolic stress and increased prevalence of electrocardiographic strain. Left ventricular diastolic diameter in C group patients was increased only when compared to A group. Frequencies of cases with more than 10 ectopic ventricular beats/hour, pairs and nonsustained ventricular tachycardia episodes were all significantly increased in C when compared to B and to A. However, only left ventricular mass index or diastolic posterior wall thickness identified independently patients with ventricular arrhythmias.

CONCLUSION

Left ventricular hypertrophy is the main predictor of potential high risk rhythm disturbances in hypertension.

[Role of blood pressure in rest and exercise conditions and importance of clinical factors in left ventricular hypertrophy in arterial hypertension]

PURPOSE

To evaluate the role of casual and exercise blood pressure as well as the importance of clinical factors on the presence and degree of left ventricular hypertrophy in hypertension.

METHODS

Fifteen normotensives (control group) and 30 hypertensives, 14 of them with and 16 without left ventricular hypertrophy (groups with LVH and without LVH, respectively) were studied. LVH diagnosis was established when mass index was higher than 2 standard-deviations of the mean values calculated for each sex in control group. Resting, casual determined, and bicycle exercise systolic and diastolic blood pressures along with age, body surface area, sex and race distribution were compared between groups. In addiction, their relation with mass index as independent variables were also tested.

RESULTS

Hypertensives in group with LVH had higher diastolic septal, posterior wall, and relative wall thicknesses. No significant statistical difference was observed neither in sex and race distribution, nor in age and body surface area between groups. Otherwise, there were significant differences in both resting and exercise blood pressure. In the entire population studied, left ventricular mass index significantly correlated with age (r=0,33, p=0,03) as well as with both casual (systolic - r=0,72, p=0,0001; diastolic - r=0,69, p=0,0001) and exercise (systolic - r=0,62, p=0,0001; diastolic - r=0,66, p=0,0001) blood pressures. However, linear regression analysis demonstrated that only resting systolic (p=0,0001) and exercise diastolic (p=0,0303) blood pressures were significant and independent determinants of mass index.

CONCLUSION

Resting and exercising blood pressures are the main determinants of left ventricular hypertrophy in hypertension.

Clinical and electrophysiologic features of syncope in chronic chagasic heart disease

INTRODUCTION

Syncope in patients with chronic Chagasic heart disease (CCHD) is a frequent but poorly studied problem.

METHODS AND RESULTS

Fifty-three patients with CCHD and recurrent syncope were followed for 2 to 127 months. They were classified into the following groups: G-I (n = 15) without inducible ventricular tachycardia (VT) and normal HV interval; G-II (n = 17) with only inducible VT; G-III (n = 11) with only an abnormal HV interval; and G-IV (n = 10) with both an inducible VT and an abnormal HV interval. Empiric pharmacologic therapy was given in G-I; pharmacologic therapy guided by electrophysiologic study in G-II; atrioventricular pacing in G-III; and empiric pharmacologic with atrioventricular pacing in G-IV. Age and sex were similar among groups; New York Heart Association Functional Class I symptoms were more prevalent (P = 0.0001) in G-I. The ejection fraction by echocardiography was higher in G-I (P = 0.0122). The density of premature ventricular complexes by Holter monitoring was similar among groups. The complexity of premature ventricular complexes by Holter was significantly higher in G-II (P = 0.0270); this variable, analyzed from the exercise electrocardiogram, was not different among groups. All deaths were sudden, prevalence was higher in G-II and absent in G-III, and recurrence of syncope was similar among groups.

CONCLUSION

The most probable causes of recurrent syncope were VT (43%) with poor prognosis, and paroxysmal atrioventricular block (21%) with a favorable prognosis. Absence of congestive heart failure, complexity of premature ventricular complexes by Holter, and absence of intraventricular heart block showed statistical correlation with normal electrophysiologic study, inducible VT, and normal HV interval, respectively.

[Value of computerized exercise stress test in the differential diagnosis of ischemic phenomena of obstructive versus nonobstructive origin]

PURPOSE

To describe groups of patients who have obstructive and non-obstructive coronary artery disease, through computadorized exercise stress test.

METHODS

The test was done in 121 patients, all male, divided into 3 groups: GN group, 50 patients with normal electrocardiographic response to exercise; GLO group, 40 patients with obstructive coronary artery disease and GNO group, 31 patients with normal coronary arteries, showing one or more of the following entities: intramural coronary traject, coronary tortuosity, slow flow, mitral valve prolapse or left ventricular hypertrophy. GLO and GNO groups presented with abnormal response of the ST segment during exercise. The quantitative variables registered by computer were particularly analyzed as follows: STL (point Y depression), slope, index and ST segment integral. The magnitude of ST vector was visually measured and quantified. The statistic study was made through ANOVA and multiples comparison by the Scheffe's method, Fisher's test, quisquare and sensibility, specificity and accuracy calculation.

RESULTS

There was a significant statistic difference among the 3 groups relative to slope and index (p < 0.05). The integral variable of ST segment did not allow us to differentiate the GLO and GNO groups. In the association study between the ST vector magnitude and abnormal T loop, there was an increase in sensibility of 15% in the exercise stress test.

CONCLUSION

The ST segment slope below zero values, define patients having obstructive disease, and the opposite, non-obstructive disease. Values of ST segment index lower than -2 are linked to obstructive disease and higher than -2 linked to non-obstructive. Values of ST segment lower than -7 microV. s separate individuals with normal exercise stress test from those with ischemic type response. The magnitude of ST vector equal to or lower than 0.20mV define normal vectorcardiographic response to the exercise.

[Cardiopulmonary exercise test in the evaluation of healthy elderly men]

PURPOSE

To study methodological aspects and results of cardiopulmonary exercise tests in elderly.

METHODS

Twenty-five men (mean age 65 +/- 5 years) performed a cardiopulmonary exercise test using a bicycle ergometer and a progressive continuous work load increase protocol was employed. A computadorized system (2001 CAD/Net System-MGC), which includes a gas analyser and a pneumotacograph, was used for on line monitoring of oxygen and carbon dioxide expired fraction and also of pulmonary flow.

RESULTS

We observed the following values of oxygen uptake, pulmonary ventilation and respiratory gas exchange: rest=4 +/- 1 ml/kg-1/min-1, 11 +/- 2 l/min-1 and 0.80 +/- 0,1, respectively: anaerobic threshold=12 +/- 3 ml/kg-1/min-1, 29 +/- 6 l/min-1 and 0.90 +/- 0.1, respectively: respiratory compensation point=18 +/- 4ml/kg-1/min-1, 47 +/- 1 l/min-1 and 1.07 +/- 0.1, respectively, and peak of exercise = 13 +/- 5 ml/kg-1/min-1, 76 +/- 18 l/min-1 and 1.21 +/- 0.2, respectively. The anaerobic threshold and the respiratory compensation point were achieved at 53 +/- 11 and 77 +/- 9% of peak oxygen uptake respectively. The elderly shown slightly increased values of the relation volume dead/tidal volume at rest with a slightly smaller decrease of its values during exercise in comparison to data obtained from young healthy untrained subjects. The heart rate prescription for exercise based on the heart rate reserve was higher than that based on the cardiorespiratory and metabolic responses (113-126bpm vs 96-114bpm).

CONCLUSION

The cardiorespiratory and metabolic responses pattern in the elderly is quite heterogeneous. The heart rate prescription for exercise based on conventional stress tests seems to overestimate cardiorespiratory and metabolic capacity in healthy elderly men. The determination of anaerobic threshold and respiratory compensation point from cardiopulmonary exercise test data optimize exercise prescription for healthy elderly men.

[Hemodynamic evaluation during isotonic exercise of patients with orthotopic heart transplantation]

PURPOSE

To evaluate the hemodynamic response of patients submitted to orthotopic heart transplantation during progressive isotonic exercise.

METHODS

Eight patients who underwent orthotopic heart transplantation have been evaluated through invasive hemodynamic study during isotonic exercise. The mean right atrial pressure (RAP), pulmonary artery pressure (PAP), pulmonary artery wedge pressure (PAWP), arterial blood pressure (ABP), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), heart rate (HR) and cardiac output (CO) have been determined in three distinct situations: at rest in the supine position (R), at rest with the legs up (RU) and during progressive isotonic exercise (E). The hemodynamic results at rest have been compared to the ones before transplantation. Phase RU and E results have been compared with each other.

RESULTS

Comparing to the phase before transplantation at the R phase we found normalization of mean PAP (34.9 +/- 14.0 to 17.0 +/- 3.5 mmHg), RAP (7.3 +/- 4.3 to 2.9 +/- 1.9 mmHg) and CO (2.9 +/- 0.98 to 5.7 +/- 0.99 l/min), otherwise there was an increase in HR (89 +/- 15 to 94 +/- 13 bpm) mean ABP (84 +/- 25 to 115 +/- 12 mmH) and SVR (30 +/- 15 to 22 +/- 7 units Wood), (p < 0.05). Comparing phase E to phase RU, there was a significant increase in RAP (3.1 +/- 1.8 to 9.4 +/- 3.9 mmHg), mean PAP (21.0 +/- 2.8 to 37.0 +/- 10.0 mmHg), PAWP (8.1 +/- 2.1 to 15.0 +/- 5.8 mmHg), CO (5.8 +/- 0.8 to 9.9 +/- 2.4 l/min), HR (93 +/- 8 to 116 +/- 18 bpm) and a decrease in SVR (22.0 +/- 3.0 to 13.3 +/- 3.8 units Wood), (p < 0.05), otherwise there was no statistically significant modifications in PVR (2.2 +/- 0.7 to 2.3 +/- 1.2 units Wood) and mean ABP (129 +/- 12 to 129 +/- 15 mmHg), (p = NS).

CONCLUSION

Patients submitted to heart transplantation may improve cardiac output mainly from increasing in stroke volume, associated with an increase in RAP and PAP. Nevertheless, the improvement increase in CO is compatible to exercise capacity after heart transplantation.