[Angina pectoris--particular aspects in the elderly]

The incidence of the coronary heart disease increases dramatically with age, representing in Portugal the second largest cause of death in patients older than 65 years. The cause of this high prevalence of the disease is not completely understood, but the pathogenic role of the cardiovascular risk factors has a singificative importance. It seems to be essential, even in elderly, to control these risk factors in order to limit the progression of the atherosclerotic disease. Regarding symptomatology, effort dyspneia appears to be one of the most frequent disease manifestations, differing from the typical chest pain presentation observed in the younger patients. Exercise stress testing can be used safely in the elderly and it is not just an important diagnostic tool, but it is also essential to the stratification of the patients to be more agressively treated. Concerning treatment, the search and correction of the precipitating factors are a key to success in the elderly patients. Pharmacologic therapy must be prescribed in agreement with the clinical pharmacologic principles, carefully adjusted to the elderly, in order to avoid adverse drug effects. In spite, coronary bypass surgery has some higher risk in the elderly. The results obtained are satisfactory, and the patients subset with ventricular disfunction, benefit the most. Percutaneous transluminal coronary angioplasty constitutes a very atractive therapeutic modality in the elderly. Cardiac reabilitation programe are very useful in the elderly, contributing to the desired psycosocial reintegration of these patients.

A minimal lentivirus Tat

Transcriptional regulatory mechanisms found in lentiviruses employ RNA enhancer elements called trans-activation responsive (TAR) elements. These nascent RNA stem-loops are cis-acting targets of virally encoded Tat effectors. Interactions between Tat and TAR increase the processivity of transcription complexes and lead to efficient copying of viral genomes. To study essential elements of this trans activation, peptide motifs from Tats of two distantly related lentiviruses, equine infectious anemia virus (EIAV) and human immunodeficiency virus type 1 (HIV-1), were fused to the coat protein of bacteriophage R17 and tested on the long terminal repeat of EIAV, where TAR was replaced by the R17 operator, the target of the coat protein. This independent RNA-tethering mechanism mapped activation domains of Tats from HIV-1 and EIAV to 47 and 15 amino acids and RNA-binding domains to 10 and 26 amino acids, respectively. Thus, a minimal lentivirus Tat consists of 25 amino acids, of which 15 modify viral transcription and 10 bind to the target RNA stem-loop.

[Myocardiopathy caused by Portuguese-type familial amyloidotic polyneuropathy. Sequential morphologic and functional study of 60 patients]

AIM OF THE STUDY

To assess the cardiac involvement of familial amyloidotic polyneuropathy--Portuguese type (FAP) in a prospective study.

INTRODUCTION

FAP is a sensitive, motor and autonomic familial polyneuropathy, due to amyloid deposits on nerve and vascular structures, related to abnormal transthyretin synthesis. FAP is a progressive systemic disease. The associated cardiomyopathy is well characterized in the Japanese form, but studies on FAP--Portuguese type cardiomyopathy remains controversial, regarding its occurrence and clinical and morphofunctional aspects.

POPULATION

The Authors studied 60 Portuguese caucasoid patients, belonging to 55 different families: 23 women from 27 to 67 years old (m = 40.78 +/- 18.4) and 37 men, from 31 to 60 years old (m = 40.8 +/- 12.8). The diagnosis was established by characteristic clinical aspects, electromyograms and nerve or gut biopsies, positive for amyloid. Patients were classified in phases from I to VI according to the severity of neurological involvement and disability.

METHODS

All the patients carried out clinical evaluation, thorax X-Ray, conventional EKG, Holter EKG (20-24 hours), M + 2D echocardiography and phonocardiography. Morphological and functional data were obtained from 85 echocardiographic recordings; special attention was paid to the evidence of structural abnormalities, evaluation of internal chamber dimension, left ventricular mass and systolic function indexes (left ventricular fractional shortening, left ventricular ejection fraction, left ventricular end-systolic stress index and Vcf).

CONCLUSIONS

Suggestive aspects of pericardial and myocardial amyloid infiltration were found even in the earliest phases of the disease; all the records of patients in advanced phases (III to VI) were abnormal. The most frequent abnormalities founded were: a bright sparkling pericardial and myocardial echo pattern and increased ventricular wall thickness, with increased left ventricular mass index in 85% of patients in phases III to VI. Vcf was abnormally increased when plotted together with left ventricular end-systolic stress index, which was normal or decreased, probably reflecting "excessive" inotropism, in 1/3 of patients in phases III to VI. Systolic function was never depressed; no cardiac chamber enlarged. So, this study points out the presence of an infiltrative and/or hypertrophic cardiomyopathy in FAP--Portuguese type; suggestive aspects of diastolic dysfunction and decrease in systolic function were recorded. However, in the clinical setting of FAP, symptoms and signs like dyspnea, fatigue, oedema, may not be diagnosis of congestive heart disease.

Plasma catecholamines and postural hypotension in familial amyloidotic polyneuropathy of the Portuguese type

Plasma adrenaline and noradrenaline levels were measured while supine and following head-up tilt to 45 degrees, in both normal controls and in patients with familial amyloidotic polyneuropathy of the Portuguese type. In nine patients systolic blood pressure fell by less than 15 mmHg, while in seven patients it fell by more than 15 mmHg. Plasma noradrenaline rose during tilt in the majority of patients, as in the controls. There was no correlation between levels of catecholamines and fall in blood pressure on head-up tilt. The data excludes widespread sympatho-neural failure as a cause for postural hypotension in familial amyloidotic polyneuropathy of the Portuguese type. The results are compatible with either segmental/patchy sympathetic denervation or dysfunction of the receptor/effector mechanisms in target organs such as the heart and blood vessels.

[Neurophysiologic study of the phrenic nerve]

Phrenic nerve conduction was studied in 19 volunteers using two different percutaneous methods of stimulation, mono and bipolar. A response was obtained in all nerves studied. The results are comparable using mono or bipolar stimulation method. No significant difference in latency, amplitude, or intensity stimulation applied was found between left and right sides. There was no correlation of age or height with the latency. Latencies above 10 ms or differences between right and left above 1.6 ms are abnormal values. We studied two patients with neurological disorders, one of them with Guillain-Barré syndrome and the other with a bulbar form of Amyotrophic Lateral Sclerosis and respiratory failure. Both of them had prolonged conduction time. This method permits reliable analysis of localized phrenic lesions and abnormalities induced in either the phrenic nerveor diaphragm by generalized disease processes.

Mutational analysis of the equine infectious anemia virus Tat-responsive element

A hairpinlike structure is predicted to exist at the 5' end of equine infectious anemia virus (EIAV) RNA which is similar in many ways to the human immunodeficiency type 1 (HIV-1) Tat-responsive element (TAR). In EIAV, this structure has a shorter stem than in HIV-1 and lacks the uridine bulge. Primer extension analysis of EIAV RNA was used to identify the transcriptional start site in the viral long terminal repeat. Premature termination of primer elongation at the predicted double-stranded RNA region was frequently observed and suggests that the inferred hairpin structure exists under these conditions. We have functionally characterized EIAV TAR by site-directed mutagenesis and transient gene expression analysis. It is demonstrated here that the secondary structure of this element is essential for Tat action. Mutations that disrupted base pairing abolished TAR function, and compensatory mutations that restored the stem structure resulted in Tat activation. The TAR loop appears to be closed by two U.G base pairs that are likely to provide a unique structural motif recognized by the Tat protein. With one exception, substitutions of nucleotides within the EIAV loop sequence decreased TAR function. All nucleotide substitutions of the cytidine at position +14 increased EIAV Tat responsiveness; however, its deletion abolished trans activation. Our results lead us to propose that the EIAV and HIV-1 Tat systems employ closely related cis- and trans-acting components that probably act by the same mechanism.

[Thrombolysis in acute myocardial infarction in the aged. A greater risk of cardiac rupture?]

OBJECTIVE

To evaluate age group and i.v. thrombolytic therapy (TT) influences on cardiac rupture complicating acute myocardial infarction (AMI). CONCEPTION: Retrospective analysis of patients (pts) admitted during 1988-89 to an Intensive Care Unit of a Terciary Hospital (UCIM) with AMI.

POPULATION

430 pts were admitted with AMI. During this period 89 pts were submitted to TT (25% age greater than or equal to 65 years). Eighty four pts died during hospital stay and 42 had autopsy study (50%). Only 7 of nonautopsied pts died of undetermined cause. Dead pts had age m +/- SD 72 +/- 11 years old (yo) (37% female, 63% male and 74% age greater than or equal to 65 yo).

RESULTS

Nineteen pts died of cardiac rupture (CR) (23%). CR prevalence was 1.4% (3/218) in pts less than 65 yo and 7.5% (16/212) in pts greater than or equal to 65 yo (p less than 0.01). CR prevalence in pts submitted to TT (4.5%) 4/89, was similar to pts not submitted to TT (4.4%) 15/341 (n.s.). Pts less than 65 yo had nonsignificant differences in CR wether submitted or not to TT (0% vs 2%). Elderly pts (greater than or equal to 65 yo) CR prevalence was 18% (4/22) in those submitted to TT vs 6% (12/190) in those not submitted to TT (p less than 0.05).

CONCLUSIONS

Thrombolytic therapy may carry an additional risk for cardiac rupture in elderly patients (greater than or equal to 65 yo).

[X syndrome: review of concepts]

Patients with syndrome X or microvascular angina present complains of effort angina associated with normal--appearing coronary arteries. Ischemia seems to be caused by myocardial perfusion abnormalities, related to microcirculatory disfunction, characterized by excessive vasoconstriction and/or inadequate vasodilation response. The intimal cause of this microcirculatory disfunction, located in the small pre-arteriolares arteries with 100-200 microns caliber, is still unknown. It seems that these patients present a generalized abnormality of the systemic smooth muscle, affecting territories other than the vascular. The diagnosis should be suspected whenever a patient presents effort angina, angiographically normal arteries and evidence of ischemia to exercise. As this syndrome is better understood some subsets of patients with different clinical characteristics and prognosis, are being identified. The calcium channel blockers seem to be the drug more effective in the control of ischemia and symptoms. The prognosis is, in general, better than in patients with coronary angiographic lesions.

[Value of the ergometric test after myocardial infarction]

Exercise stress testing (EST) after myocardial infarction helps to define the clinical subsets of patients at high and low risk. It should be performed before hospital discharge, unless a contraindication exists. In order to exclude false positives, EST must be repeated 4-6 weeks later. EST helps to recognize the presence of residual ischaemia. Significant ST segment depression during exercise, associated or not with angina, is the most important indicator of ischemia. These patients with ischaemia at distance i.e., those with ST segment changes in ECG leads without W waves, are at high risk. Some continuous exercise variables (degree of ST deviation, time of recovery and exercise duration) are related to cardiac mortality. Exercise induced complex ventricular arrhythmias seem to be related to left main or three vessels disease, and a greater likelihood of sudden death, particularly when coexist a low ejection fraction, important segmentar disturbances of contractility and ST segment depression. EST after myocardial infarction has great value to assess the results of medical therapy and/or coronary angioplasty or bypass grafting. EST also constitutes a valuable clinical tool to support a comprehensive rehabilitation programme.

Spinal cord compression secondary to idiopathic retroperitoneal fibrosis

Retroperitoneal fibrosis is a rare disorder in which the abnormal fibrotic tissue compresses retroperitoneal organs. In the majority of patients no obvious cause can be found, hence the name idiopathic retroperitoneal fibrosis. The process can also arise from other anatomic areas, suggesting a multifocal origin. We report a case of dorsal epidural compression in a 63-year-old patient harboring idiopathic retroperitoneal fibrosis. A magnetic resonance imaging scan revealed the precise location of the lesion. It is suggested that retroperitoneal fibrosis should be considered in the differential diagnosis of epidural spinal cord compression.

[Rhythm profile in patients with psoriatic arthritis]

OBJECTIVE

To analyze the rhythmic profile in patients with psoriatic arthritis (PA).

DESIGN

In order to evaluate the rhythmic profile of patients with PA, we have carried out ambulatory 24 hour ECG recordings in 22 patients presented consecutively to the Holter ECG laboratory.

SETTING

Patients followed in a specialised rheumatology consultation, in Santa Maria Hospital.

PATIENTS

We have studied 22 patients (pts), 10 male and 12 female, aged 49.8 +/- 8.4 years, presenting PA diagnosed in average 12.9 years before. A group of 36 individuals, 25 male and 11 female, aged 37 +/- 8 years and without disease, were used as control.

RESULTS

All patients were in sinus rhythm with a mean heart rate of 71 +/- 6 (min - 51.5 +/- 7.0 and max - 130.3 +/- 15.0). In 8 (36.6%) there were sinus bradycardia less than 50/min and sinus tachycardia (greater than 120/min) in 15 patients (68.1%). Two patients (9%) presented supraventricular tachycardia and one had AV block. There were premature atrial systoles in 14 pts (63.6%), and ventricular arrhythmias in 9 (40.9%). In control group, there were sinus bradycardia in 16.6%, sinus tachycardia in 33.3%, premature atrial systoles in 33.3% and ventricular arrhythmias in 25% of them; in 11% there were conduction disturbances.

CONCLUSIONS

a) Premature atrial systoles were the rhythm disturbance more prevalent. b) Patients with PA presented a significant higher incidence of sinus bradycardia and sinus tachycardia. c) Cardiac conduction disturbances were not frequent. d) Our results may suggest the presence of a subtle autonomic dysfunction in patients with psoriatic arthritis.

[Equilibrium radionuclide angiography in patients with previous myocardial infarct. Correlation with electrocardiogram and coronarography]

Fifty five patients with previous myocardial infarction (MI), 47 male and 8 female, mean age 55.5 +/- 8.9 years, have been studied in order to correlate the alterations found on the equilibrium (gated) radionuclide angiogram (RNA) with the location of the MI on the electrocardiogram of the obstructive lesions on coronary angiographies. Of the 55 patients studied, 22% showed no regional wall motion abnormalities (WMA). Both MI with and without Q wave may show WMA, which are significatively more frequent in patients with anterior MI on the ECG and with occlusive lesions (greater than 90%) on coronariographies. Regional localization of the WMA on the RNA does not identify the localization of the obstructive lesions. Hypokinesia was the most frequent type of WMA found both with occlusive (greater than 90%) and sub-occlusive (greater than 75%) lesions. Low values of the ejection fraction (less than 45%) were found in the presence of WMA and occlusive artery lesions.

[Maximal values of serum creatine phosphokinase and its myocardial fraction in acute myocardial infarct. Correlation with a previous history of ischemic cardiopathy]

OBJECTIVE

To evaluate the importance of preinfarction angina as a determinant of infarct size.

DESIGN

Retrospective study of patients (pts) with acute myocardial infarction (AMI).

SETTING

Patients admitted to an Intensive Care Unit of a University Hospital.

PATIENTS

The study concerns 224 pts, 161 men women, aged 63.09 +/- 11.92 years, who did not receive thrombolytic or intravenous beta-blocking therapy and in whom it was possible to establish the presence or absence, of previous ischemic heart disease.

METHODS

Patients, were divided in 2 groups: A (1st AMI, 172 dts - 123 M, 49 F) and B (2nd AMI, 52 dts - 38 M, 14 F). These groups were subdivided according the presence of preinfarction angina (A1, B1) or its absence (A2, B2). The infarct size was evaluated by peak values of CK/CKMB.

RESULTS

Group A: CK/CKMB--959/101; Group B: CK/CKMB--742/77 (p-NS). Subgroups--A1: CK/CKMB--1143/118; A2: CK/CKMB--725/78 (p less than 0.001); B1: CK/CKMB--635/59; B2: CK/CKMB--818/88 (p-NS). The analysis of CK/CKMB values distribution, according to the affected cardiac wall, has shown an identical correlation.

CONCLUSION

1--The larger infarct size in subgroup A1 (1st AMI without angina) suggests a protective effect by collateral circulation in subgroup A2 (1st AMI with angina). 2--The larger infarction (although not significantly) in group A (1st AMI), correlates with less viable muscle in group B (2nd AMI). 3--The higher values of CK/CKMB in group B2 (2nd AMI with angina) can be expected given the presence of residual ischemia. 4--The absence of the protective role by collateral circulation in patients of subgroup A1 (1st AMI without angina) suggests for them a stronger indication for thrombolytic therapy.

[Silent ischemia in patients with previous myocardial infarct. Correlation of Holter and coronarography]

OBJECTIVE

Our objective was to determine the presence of silent myocardial ischemia and the degree of coronary obstructions.

DESIGN

Successively patients with myocardial infarction.

SETTING

Patients admitted to the coronary intensive care, later followed in a specialised out-patients consultation.

PATIENTS

62 patients with previous myocardial infarction.

INTERVENTIONS

All the patients were submitted to Holter-monitoring and coronary angiography.

RESULTS

Silent ischemia was present in 14 (22,6%) of the patients. Seven of these (50%) had 3 vessels disease, 2 (14,3%) had 2 vessels disease, and 5 (35,7%) had 1 vessel disease. Twelve of the patients (86%) had occlusive lesions (greater than 90%), localised in 11 (79%) in the third proximal segment of the artery.

CONCLUSIONS

Our results showed that the presence of silent myocardial ischemia was predominantly associated with 3 vessels disease, and with lesions of more than 90% of occlusion, localised in the 1/3 proximal of the vessel. Patients with previous myocardial infarction and silent ischemia may belong to a subgroup with surgical indication. And so, Holter studies in these patients should be followed by angiographic studies for localization of the obstructive lesions.

Ultrasound-guided brain abscess aspiration in neonates

Four cases of brain abscess in neonates are described, diagnosed by ultrasonography and CT. All abscesses were confirmed surgically. One patient was operated on 5 weeks after diagnosis because of initial parental refusal. The etiology in all cases was meningitis superimposed on an hypoxic-ischemic insult. Two cases had a single abscess while the other two had multiple lesions. All cases were operated on with intraoperative ultrasound examination through the fontanelle. The case with delayed aspiration showed complete evolution from localized cerebritis to complete capsule formation with mass effect. One abscess was sterile, and in the others grew Klebsiella pneumoniae and Enterobacter aerogenes. The microorganism initially isolated from the lumbar CSF was also found in the abscess. Even after sterilization of the lumbar CSF, all abscesses were still present. Ultrasound examination and CT are compared.

Reflex increases in heart-rate induced by perfusing the hind leg of the rat with solutions containing lactic acid

The hypothesis that metabolic receptors in skeletal muscle influence heart-rate during exercise was tested by means of a perfused preparation of the rat's hind legs. The isolated leg was connected to the body only by nerve and bone and was perfused with tyrode solution. The humoral changes of exercise were simulated by perfusing with modified tyrode solutions in which concentration of K+, osmolality, concentrations of lactic acid, and inorganic phosphate were changed to reflect to those occurring during heavy exercise. Only perfusion with a solution enriched with lactic acid elicited a significant increase in heart-rate. The response disappeared when the nerve supply to the leg was cooled or sectioned. 20-60 s after the start of perfusion with solution of high [lactic acid] heart-rate began to increase reaching a maximum (delta HR +/- SE = 20.2 +/- 8.2, n = 7) after about 2 min. The effect on heart-rate increased when the venous concentration of lactic acid was increased the range from 3 to 10 mmol/l. In further experiments, we tried to separate the effects of pH and lactate. Heart-rate responses were induced only at low pH and at low pH the extent to which heart-rate changed increased with increases in lactate concentration.

Persistent dysarthria with apraxia associated with a combination of lithium carbonate and haloperidol

Reported is a 19-year-old manic-depressive patient who developed persistent dysarthria with coexisting apraxia while on a combination of high dose haloperidol and lithium carbonate. The speech disability occurred as a solitary symptom in a patient with normal serum lithium levels and no other signs or symptoms of lithium toxicity and persisted after lithium was discontinued and the neuroleptic changed. There were several factors which favored an association between the speech disability and the drug therapy. These included improvement during a drug-free trial: the absence of a prior history of a speech problem; the patient's marked psychotic state and anxiety: and the high dosage of haloperidol.