[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.