Complications of endomyocardial biopsy in heart transplant patients: a retrospective study of 2117 consecutive procedures

BACKGROUND

Endomyocardial biopsy (EMB) remains the gold standard for the diagnosis of graft rejection after heart transplantation (HT). Our purpose was to evaluate the rate of complications of this invasive procedure.

METHODS

This was a retrospective study of 175 patients, who were transplanted between November 2003 and October 2010 and survived more than 1 month after surgery. We evaluated the number of inconclusive EMB and described the incidence, nature, and subsequent management of several complications associated with this procedure.

RESULTS

Over a period of approximately 7 years, we performed 2217 EMB yielding 4972 specimens, namely, an average of 2.3 fragments per procedure. The majority of EMBs (95.3%) were performed by the femoral approach. Only 12 EMB (0.57%) were inconclusive. The overall complication rate was 0.71%. During puncture, one patient experienced a vasovagal reaction and another one, a femoral artery false aneurysm. During the biopsy, there was one case of cardiac perforation with tamponade, two cases of supraventricular tachycardia, and three atrioventricular conduction abnormalities. In 19 patients, histological analysis revealed chordal tissue, but only two patients developed mild tricuspid regurgitation. We observed five cases of coronary artery fistulae. The clinical outcomes were favorable in all cases.

CONCLUSION

EMB proved to be a suitable, safe method to monitor rejection after HT.

Carvedilol: just another Beta-blocker or a powerful cardioprotector?

Beta-blockers have been used to treat ischemic heart disease, due to negative chronotropic and inotropic properties, thus inducing a decrease in myocardial consumption of oxygen and nutrients, allowing a better balance between nutritional needs and the supply provided by the coronary blood flow. Recent developments in cell biology allowed us to understand that not all beta-blockers are equal, as their intracellular mechanisms of action can be very different. This paper will focus on carvedilol, a non-selective beta-blocker with alfa-blocker properties, currently used to treat hypertension, heart failure and coronary artery disease. Effects of carvedilol on cardiac mitochondria, their relation to its antioxidant properties, and how these can improve cardiomyocyte resistance to aggression and cardiac function will be discussed. We will begin by depicting the effect of carvedilol on mitochondrial parameters, namely oxidative phosphorylation, calcium homeostasis and energy production. Then we will focus on the mitochondrial permeability transition (MPT) and how the antioxidant properties of carvedilol can be used to minimize oxidative stress, a powerful inducer of MPT. Carvedilol will also be highlighted as an enzyme modulator, focusing on its importance to prevent doxorubicin (DOX) cardiotoxicity. The mitochondrial-related mechanism of cardioprotection involving carvedilol will also be addressed, as we will discuss some clinical pieces of evidence showing the importance of mechanisms previously depicted. In conclusion, based upon its molecular mechanisms of action, carvedilol seems to be a unique beta-blocker. These unique characteristics can help us understand the positive impact of carvedilol on the prognosis of patients with heart disease.

Biventricular pacing--early experience

INTRODUCTION

Biventricular pacing has been studied for the treatment of chronic heart failure (CHF). This technique seems to be able to improve symptoms and exercise tolerance, in patients with advanced CHF and prolonged QRS duration.

OBJECTIVE

To present our experience with biventricular pacing in the management of severe CHF.

METHODS

Between June 2000 and March 2001, 8 patients with dilated cardiomyopathy and left bundle branch block (LBBB) were selected for transvenous biventricular pacing system implantation. Mean age: 54.12 +/- 16.8 years; 5 males. The etiology was: idiopathic in 6 cases; operated congenital heart disease in 1, and ischemic in the other. Despite tailored treatment of CHF (with all patients taking diuretics and angiotensin-converting enzyme inhibitors), 7 patients remained in NYHA class III and 1 in IV. The quality of life score (assessed by the "Minnesota living with heart failure questionnaire") was 62.25 +/- 11.29. Seven patients had sinus rhythm and only one chronic atrial fibrillation; mean PQ duration--220 +/- 76.37 ms; mean QRS duration--168.75 +/- 20.31 ms.

RESULTS

Implant failure, due to coronary sinus dissection and to excessive fluoroscopy time, with no coronary sinus catheterization, occurred in 2 cases (success rate: 75%). Implant data: mean implant procedure duration: 122.5 +/- 47.82 min; mean fluoroscopy time: 35.66 +/- 22.06 min; QRS duration, after implant: 133.33 +/- 15.05 ms. Left ventricular lead final position: anterolateral in 2 patients and lateral in 4. Pacing thresholds: biventricular--1.36 +/- 0.6 V; right ventricle--0.28 +/- 0.04 V; right atrium--0.32 +/- 0.08 V. Pacing impedance (left ventricle): 1013.33 +/- 147.87 omega. Follow-up (1st and 3rd month): one patient died, suddenly, 15 days after the procedure. In the others, an improvement in the quality of life index and functional class was found. These results were independent of echocardiography data. There were no significant differences in the pacing threshold and impedance during the follow-up.

CONCLUSIONS

Patients with advanced CHF and widened QRS benefited from biventricular stimulation, in which improvement on the clinical status was evident.

[Mitral flow propagation velocity assessed with M-mode color Doppler in patients with dilated cardiomyopathy]

BACKGROUND

The role of diastolic disfunction in the setting of severe left ventricular (LV) disfunction is usually forgotten due to difficulties in quantification and interpretation. The propagation velocity (PV) of mitral inflow into the left ventricle has been proposed as a load independent indicator of LV diastolic function. Our aim was to correlate PV with age, body surface, chambers dimensions, wall thickness and with classic parameters of systolic and diastolic function. We had in mind the validation of this index in the quantification of LV filling and in risk stratification of patients with dilated cardiomyopathy (DC).

MATERIAL AND METHODS

We prospectively studied 32 consecutive patients, mean age 56.1 +/- 15.7 years, 22 (68.75%) male, mean ejection fraction 28.1 +/- 7.5%. All of them were in NYHA class < or = II and on ACE inhibitors. Eight (25%) were on beta-blockers. Patients without sinus rhythm, paced or with significant hypertensive, congenital or valvular heart disease were previously excluded. The following parameters of LV systolic function were assessed by echocardiography: fractional shortening, ejection fraction and cardiac output. LV filling was assessed by transmitral flow pulsed Doppler analysis: isovolumic relaxation time (IVRT), peak E and A wave velocities, E wave deceleration time (DT). We also evaluated a new Doppler index of combined systolic and diastolic myocardial performance (Tei index). PV (cm/s) was calculated by Color M-mode. Univariate regression analysis was performed (PV as dependent variable).

RESULTS

We detected a high prevalence of diastolic function disturbances: 25 (78.1%) patients with a delayed relaxation pattern and only 3 (9.4%) with a restrictive pattern. PV did not correlate with age, body surface and LV geometry. There was a significant correlation between PV and E/A ratio (r = 0.61; p < 0.0001), IVRT (r = -0.50; p = 0.006), DT (r = -0.41; p = 0.01) and Tei index (r = -0.36; p = 0.04).

CONCLUSIONS

Our results indicate that, in patients with a predominance of delayed relaxation, there is a strong relationship between PV and the classic parameters of LV filling. For similar levels of systolic impairment, PV could be an easy, fast and reproducible quantitative indicator of severity on DC.

Autonomic function in chronic liver disease assessed by Heart Rate Variability Study

BACKGROUND

Chronic liver disease is associated with cardiovascular changes, including hyperdynamic circulation with increased blood volume and cardiac output, and with reduced peripheral vascular resistance. Autonomic dysfunction is a common finding in these patients, being involved in the pathogenesis of the hyperdynamic condition. The aim of our study was to evaluate autonomic function in cirrhotic patients by using the 24 hour Heart Rate Variability study. We also sought to relate the degree of autonomic dysfunction with the severity of the liver disease.

MATERIAL AND METHODS

We studied 22 cirrhotic patients, 50% of whom were male, mean age 44.14 +/- 11.32 years. The etiology was alcohol related in 12 (54.6%), virus hepatitis in 6 (27.2%), autoimmune related in two (9.1%) and other in the remaining two (9.1%). In terms of severity liver disease 6 patients were in Child-Pugh's class A (27.3%), 9 in Child-Pugh's class B (40.9%) and 7 in Child-Pugh's class C (31.8%). Thirteen patients (59%) had ascites. Both patients and 20 age-sex matched healthy volunteers underwent 24 hour ECG Holter study with assessment of Heart Rate Variability (time and frequency domains).

RESULTS

The cirrhotic patients showed severe decrease in Heart Rate Variability when compared to healthy volunteers: SDNN (84.14 +/- 35.78 ms vs 148.9 +/- 33.97 ms; p < 0.0001), pNN50 (3.54 +/- 4.61 vs 11.17 +/- 9.88; p = 0.004). The spectral analysis revealed markedly decrease of average total power, with reduction of all components (VLF, LF, HF), in the absence of significant difference in LF/HF ratio (2.52 +/- 1.40 vs 2.98 +/- 1.57; p = NS). Ascites had relationship with more pronounced autonomic impairment: SDNN (70.31 +/- 30.32 ms vs 104.11 +/- 34.97 ms; p = 0.03). On the other hand, alcohol related etiology did not influence Heart Rate Variability parameters. Moreover, we found significant positive correlations between SDNN (dependent variable) and Prothrombin activity (r = 0.64; p = 0.001), as well as with Serum Albumin (r = 0.40; p = 0.05), but not with Total Bilirubin (r = -0.14; p = 0.51). Prothrombin activity was the only independent predictor of autonomic dysfunction.

CONCLUSION

Chronic liver disease is accompanied by a significant Heart Rate Variability decrease. Alcohol related etiology does not indicate further autonomic dysfunction. The greater the hepatopathy severity, the greater the Heart Rate Variability impairment. Hepatocellular dysfunction indicators have more accuracy to demonstrate autonomic disturbances than cholestasis indicators.

Permanent pacing in patients with congenital atrio-ventricular block--experience of 33 cases

OBJECTIVES

The authors review permanent pacing in patients with congenital atrioventricular block (CAVB) and present their experience in permanent pacing in this pathology.

STUDY POPULATION AND METHODS

In a population of 4,355 patients submitted to implantation of permanent pacing between January 1980 and January 1998, 33 (0.75%) had CAVB. The mean age of the patient population with CAVB was 16.7 years (aged from eleven days to 35 years); 33% were below 10 years of age; 16 patients were male. The majority of the patients had symptoms of brain hypoperfusion; two patients had concomitant malignant ventricular tachyarrythmias (one of these with Torsade de Pointes due to congenital long QT syndrome). Transvenous (endocardial) pacing was used in 32 patients (two with previous epicardial pacing and exit block) and epicardial pacing in one. The mode of stimulation used was VVI in three patients, DDD in eight patients, VVIR in 14 patients, DDDR in four patients and VDD in four. Smaller pulse generators were used in children of lower weight. In recent years single lead VDD systems have been preferred whenever technically possible. Vascular access was the left cephalic vein in 17 patients; the left subclavian vein in 14 patients and the right jugular vein in one patient. During a mean follow-up of 6.9 years, two patients with ventricular stimulation systems developed "Pacemaker Syndrome" and required a change of mode of stimulation. Lead fracture and posterior cutaneous necroses were observed in two other patients, who were accordingly submitted to surgical revision. It was deemed necessary, one year later, to increase the lead loop in a child with a permanent pacemaker implanted at eleven days of age. No other complications occurred with the other patients; replacement of the pulse generators was performed in an elective manner.

CONCLUSIONS

CAVB is a rare indication for the implantation of a permanent pacemaker. In children, in the majority of cases, endocardial stimulation is possible in spite of the obvious technical difficulties due to low weight. Sequential, more physiological, stimulation systems should be preferred. However, VVIR stimulation systems of smaller dimensions can be the first choice of mode of stimulation in smaller children, mainly due to anatomical and technical limitations.

[Isolated non-compaction of left ventricular myocardium]

Noncompaction of the ventricular myocardium, also known as "spongy myocardium", is a rare congenital abnormality resulting from an arrest in the normal endomyocardial embryogenesis. The echocardiographic findings consist of multiple, prominent myocardial trabeculations and deep intratrabecular recesses in communication with the left ventricular cavity. This entity is a not well known cause of dilated cardiomyopathy. Some cases were described as X-linked familial forms. We report the clinical case of a 13-year-old female patient with severe left ventricular disfunction, a very trabeculated left ventricle on echocardiography and two admissions in class IV heart failure.

Repolarization abnormalities after catheter ablation of differently located overt accessory pathways

PURPOSE

Electrical repolarization abnormalities are usually seen after radiofrequency catheter ablation in overt accessory atrio-ventricular pathways. These abnormalities have been recognised as "cardiac memory". The aim of this study was to assess the relationships between electrical repolarization abnormalities and the location of the accessory atrioventricular pathway in the atrio-ventricular junction. We also assessed the relationship between electrical repolarization abnormalities and the degree of ventricular preexcitation.

MATERIAL AND METHODS

Our group consisted of 45 patients with overt and persistent preexcitation who were successfully submitted to radiofrequency catheter ablation. Mean age was 38.9 +/- 14.9 years (14 to 64), 28 of whom (62.2%) were male and 17 (37.8%) female. The location of accessory pathways the was left lateral in 14 patients, right posteroseptal in 14 patients, right mesoseptal in eight patients, right anteroseptal in four patients and other locations in the remaining four. Surface electrocardiograms were performed immediately following ablation, 24 hours later and three or more months after the procedure.

RESULTS

T wave abnormalities (flattened, inverted or peaked) were detected on the first day in 51% of patients, being more frequent after right accessory pathway ablation (86.9% versus 13.1% in left accessory pathways). These electrocardiographic changes were particularly frequent in patients with right mesoseptal (5/8, 62.5%) and posteroseptal (13/14, 93.3%) pathways, of which 62.5% and 71.5%, respectively, showed marked preexcitation before ablation. These findings were significantly different from those observed in patients with left lateral pathways--only 35.7% showed marked preexcitation and only two of fourteen patients (14.3%) presented T wave abnormalities after ablation. After the third month, most of the patients that had undergone successful ablation presented completed electrocardiographic normalization.

CONCLUSIONS

Patients undergoing radiofrequency catheter ablation for right accessory pathways show more frequently repolarization abnormalities than those submitted to ablation of the left lateral accessory pathways. The occurrence of these changes after preexcitation resolution may depend on the degree of previous preexcitation.

Identification of an Arg403Gln beta myosin heavy chain gene mutation in a Portuguese family with hypertrophic cardiomyopathy

INTRODUCTION

The etiology of Familial Hypertrophic Cardiomyopathy (HCM) is attributed to the mutation of genes that encode sarcomeric proteins in the heart. Until now no gene mutations had been identified in Portuguese families with HCM.

OBJECTIVE

The main objective of this study is to describe a Portuguese family with HCM carrying an Arg403Gln mutation in the beta myosin heavy chain gene.

METHODS

With the help of several Molecular Biology tools, 40 families with HCM were studied. In all these families, one member was identified as carrying an Arg403Gln mutation in the beta myosin heavy chain gene. All family members were submitted to a physical exam, EKG and echocardiography. Those carrying a gene mutation were also submitted to Holter monitoring and to magnetic ressonance imaging.

RESULTS

Molecular biology techniques are extremely important for the diagnosis of HCM, particularly in healthy carriers.

CONCLUSION

The use of molecular diagnostic tools in HCM is very useful because it allows us to identify the healthy carriers and establish earlier clinical and prevention programs for these individuals.

Haemodynamics during liver transplantation in familial amyloidotic polyneuropathy: study of the intraoperative cardiocirculatory data of 50 patients

BACKGROUND

Circulatory instability frequently complicates liver transplantation for familial amyloidotic polyneuropathy (FAP) and may be a source of surgical morbidity and mortality.

OBJECTIVE

To evaluate FAP intraoperative haemodynamic data and their relation to the duration of surgery, and need for anaesthetic drugs. RBC and sympathomimetic amines.

SETTING

Clinical study during a four year period. PATIENTS (mean +/- SD): Group I included 50 consecutive FAP ATTR Met 30 recipients of first transplantation. Age was 35.3 +/- 7.1 years, neurological score 34.3 +/- 13 in 100 and time elapsed from first symptom 5.0 +/- 2.7 years. Group II (control), not different concerning age and sex, included 51 patients transplanted during the same period with other pathologies.

METHOD

Anaesthetic protocol, monitoring and surgical techniques were similar in both groups. Data of the two groups were compared either by the Student's t-test or Fisher's exact test.

RESULTS

Low values of systemic vascular resistance index were observed in both groups, with no differences between them. Systemic arterial pressures were usually lower in group I, because cardiac index and heart rate were also significantly lower, although within normal values. However, in group I, isoflurane (a vasodilator anaesthetic) was used during less time (p < 0.05) and in lower concentrations (p < 0.01) and phenylephrine was necessary in 26% of patients vs 0 patients in group II (p < 0.001).

CONCLUSION

FAP patients presented a different intraoperative behaviour when compared to other patients submitted to liver transplantation. From a clinical point of view, the authors stress: 1--As a result of autonomic dysfunction, the administration of anaesthetic drugs to FAP patients always presents the risk of producing significant hypotension; even the use of ketamine does not prevent hypotension; 2--Safety is ensured by beat-to-beat surveillance of arterial pressures and the capacity to act immediately to support circulation; 3--These patients seem to be very sensitive to decreases in the pre-load; 4--Hypotension is also frequent with an adequate pre-load, usually as the result of low SVR; an infusion of a vasoconstrictor drug emerges as the most frequent treatment requested and our experience supports it as an effective one.

Cardiac lymphatic dynamics after ischemia and reperfusion--experimental model

ABSTRACT. The aim of the present study was to investigate the lymphatic cardiac circulation in an experimental model of ischemia plus reperfusion in mongrel dogs (Canis familiaris L). As radiotracer we used 0.2-0.25 ml (111 MBq) of 99mTc-Re2S7 colloid (+/-10 microm), injected subcapsullary below the second diagonal of the descending anterior ligated coronary artery with a special needle. A gamma-camera/Starport + DecStation were used for data acquisition. Four experimental groups with five animals each were established: G I = controls; G II = immediately after acute myocardial infarction (AMI); G III = late infarction (5 days after AMI); G IV = ischemia (90 min) + reperfusion. Four regions of interest (ROIs) were chosen: injection area (ZA), above (ZB), near right (ZD), and far right (ZC) from ZA. Mean disappearance times in ZA and dynamic parameters in the other ROIs were determined from activity/time curves drawn in each area, using homemade software. The results obtained seem to indicate that the methodology is appropriate to a detailed study of lymphatic drainage in pathological situations in animal models.

[Changes in the geometry of the heart cavities in patients with cardiac tamponade undergoing pericardial drainage]

OBJECTIVES

The objective of our study was to evaluate the changes in cardiac chamber dimension--longitudinal and transversal axis--in patients with cardiac tamponade after drainage of the pericardial effusion.

STUDY DESIGN

This is a five year retrospective study (from 1991 to 1995 inclusive) which evaluates patients with cardiac tamponade from a clinical and electrocardiographic, as well as echocardiographic, point of view.

MATERIALS AND METHODS

Thirty-nine consecutive patients with cardiac tamponade were evaluated clinically and by ECG and two-dimensional echocardiography, before and after drainage of the pericardial effusion. The drainage was done by pericardiocentesis alone in 28 cases (72%), pericardiocentesis followed by surgery in seven cases (18%) and surgery alone in four cases (10%).

MAIN RESULTS

After drainage we observed a reduction in the diameter of the pericardial effusion from 30.1 +/- 8 to 8.1 +/- 7 mm; the occurrence of jugular vein turgescence decreased from 87% to 5% (p < 0.001) and heart rate also decreased from 100 +/- 20 beats/minute to 79 +/- 17 beats/minute (p < 0.001). Systolic blood pressure increased from 107.8 +/- 20.4 mmHg to 134.6 +/- 20.3 mmHg (p < 0.001). All longitudinal and transversal diameters of the cardiac chambers increased after drainage. The greatest increase was observed in the transversal diameters of the right chambers.

CONCLUSIONS

Cardiac tamponade affects both right and left cardiac chambers which are affected in their transversal as well as longitudinal diameters; the effect of compression was more marked in the right chambers and in the transversal diameters.

True double aortic lumen in tetralogy of Fallot

In an infant with tetralogy of Fallot submitted to angiographic study, a double aortic lumen was found. Although no particular complaints were related to the additional abnormality, we report this case to emphasize the possibility of occurrence of persistent embryonic fifth aortic arch.

[Left ventricular filling in young patients with systemic lupus erythematosus in stable phase]

OBJECTIVE

The aim of this study was to evaluate the left ventricle filling pattern in patients with stable systemic lupus erythematosus (SLE).

METHODS

This prospective study was performed in 22 healthy controls and in 24 patients with stable SLE. These two groups were submitted to a clinical, electrocardiographic and echocardiographic evaluation.

RESULTS

Gender distribution and mean age were similar in both groups (p = NS). Patients with SLE were more symptomatic (21%) than control patients (0%) (p < 0.01). Left ventricular dimensions, wall thickness, and systolic function were not significantly different between the two groups. However, pericardial effusion was more frequently found in patients with SLE (21%) when compared to the control group (0%) (p < 0.05). When compared to the control group, patients with SLE showed an abnormal left ventricular filling pattern. Peak late mitral flow velocity was 0.45 +/- 0.2 m/sec in SLE patients and 0.36 +/- 0.1 m/sec in the control group (p = 0.001).

CONCLUSION

These results demonstrate that patients with stable SLE, when compared to healthy controls, are frequently associated with cardiovascular symptoms, asymptomatic pericardial effusion, and an abnormal left ventricular filling pattern.

[Hypertrophic myocardiopathy: a sarcomere disease?]

The introduction of molecular biology in Cardiology opened a new era, in which the collaboration between geneticists, molecular biologists and cardiologists will allow the clinical application of Molecular Cardiology. In this review the new advances in the diagnosis and prognostic evaluation of patients with Hypertrophic Cardiomyopathy at the molecular level are discussed. We also present a summary of our current knowledge on the genetic bases and molecular mechanisms of this disease. Finally, some possibilities of the future clinical application of the data obtained by Genetic and Molecular Biology are shown. The Molecular Biology of Hypertrophic Cardiomyopathy expanded our horizons beyond the morphologic definitions, exposing the limitations of traditional concepts. However, we should not forget the potential drawbacks of these genetic tests, in order to anticipate and prevent the problems associated with their performance.

[Role of nitrates in pharmacologic modulation of reflected waves and their significance in the treatment of arterial hypertension in the elderly]

OBJECTIVE

To analyse the efficacy of a sustained release form of isosorbide mononitrate in the treatment of isolated systolic hypertension in the elderly.

PATIENTS

24 patients suffering from essential hypertension and with an average age of 68.5 +/- 1.1 years were studied: 20 male and four female patients, all with isolated systolic hypertension (systolic blood pressure (SBP) > 160 mmHg and diastolic blood pressure (DBP) < 90 mmHg). None of the patients had received pharmacological treatment for their hypertension. None were receiving other medication or displayed concomitant pathologies.

METHODS

Assessment of all the patients was made with the measurement of their occasional blood pressure, ambulatory measurement of blood pressure and the measurement of pulse wave velocity in two arterial zones (carotid-femural) by mecanography before and after thirty days of monotherapy with a single 50 mg dose of a sustained release form of isosorbide mononitrate. Four patients were withdrawn from tests due to signs of intolerance to the drug.

RESULTS

A fall in occasional blood pressure was recorded, with statistical significance in relation to SBP only: SBP-192 +/- 15.5-->164 +/- 10.2 mm Hg (p < 0.001); DBP-85 +/- 4.2-->83 +/- 5.4 mm Hg. Ambulatory blood pressure readings also showed a significant drop in average SBP readings over the 24 hours: SAP 152.6 +/- 13.6-->140.5 +/- 15.4 mm Hg (p < 0.03); DBP 77.2 +/- 8.7-->72.3 +/- 5.47 mm Hg. No significant changes in pulse wave velocity were recorded for the zones studied: carotid-femural -20.8 +/- 6.0-->21.7 +/- 5.1 m/sec; femural-foot -4.5 +/ -1.4-->4.4 +/- 2.6 m/sec; a marked alteration in the morphology of arterial pulse in the aortic zone was observed, however, with a clear levelling off and reduction of the systolic peak.

CONCLUSION

Treatment with nitrates may be a new and effective alternative for the treatment of the age group in question. It acts specifically on the pathophysiological mechanisms of isolated systolic arterial hypertension in the elderly. Changes in reflected wave velocity (retrogrades) seem to cause the significant reduction in SBP, observed in this group of patients.

[Correlation between aortic transvalvular gradient obtained with Doppler ultrasonography and with hemodynamics study. Role of the underlying etiology]

In aortic stenosis, a good correlation was found between the gradients obtained by catheterization and Echo-Doppler. However, the correlation of these two methods in subgroups of patients with different etiologies of aortic stenosis is unknown. The aim of this study was to evaluate, whether the correlation between catheterization and Echo-Doppler was similar in patients with different etiologies of aortic stenosis. Patients with concomitant valvular disease were excluded. Only patients with a clearly defined etiology (based on clinical history, echocardiography, angiography and/or pathology) were included in this study. We evaluated 106 patients with aortic stenosis. Forty-nine patients had degenerative aortic stenosis, 32 bicuspid aortic stenosis and 25 rheumatic aortic stenosis. The percentage of male patients in each group were as follows: 57.1% in the denerative aortic group; 62.5% in the bicuspid aortic stenosis group; and 76% in the rheumatic aortic stenosis group. Mean age (years) was 69 +/- 6.7 in the degenerative aortic stenosis group, 58.1 +/- 7.5 in the bicuspid aortic stenosis group, and 64 +/- 7.1 in the rheumatic aortic stenosis group. In our study we found different correlations between the gradients obtained by the two methods-catheterization and Eco-Doppler-among the patients with different etiologies of aortic stenosis. The correlation coefficient (r2) was 0.54 (p < 0.001) in the rheumatic aortic stenosis group, 0.37 (p < 0.001) in the bicuspid aortic stenosis group and 0.21 (p = 0.001) in the degenerative aortic stenosis group. In conclusion, a good overall correlation was found between the two methods in aortic stenosis, however, this correlation is different in the three etiologies of aortic stenosis. The correlation is better in rheumatic valves, intermediate in bicuspid valves, and worse in degenerative valves. Changes in aortic valve morphology in these subgroups of patients are probably responsible for these different results.

[Classical pacemaker syndrome. Report of 2 cases with severe clinical manifestations]

We report two cases of classic pacemaker syndrome. Both patients developed severe clinical manifestations after implantation of a VVI pacemaker. One patient presented syncopal episodes and the other one manifest cardiac heart failure. Additionally, we review the mechanisms responsible for this clinical entity.

[The Bland-White-Garland syndrome or an anomalous origin of the left coronary from the pulmonary artery. Apropos a case of a continuous murmur in an adult]

The authors report a case of anomalous origin of the left coronary artery from the trunk of pulmonary artery in an adult without significant symptoms, diagnosed by the presence of a continuous thoracic murmur. Because its low incidence and great mortality in the beginning of life, the appearance in the adult is extremely uncommon, especially without symptoms of cardiac failure, angina pectoris or myocardial infarction. In the present case, the patient was asymptomatic and was submitted to various echocardiograms before the diagnosis was suspected and confirmed with angiography. Surgical treatment was performed successfully with reimplantation of the anomalous vessel in the aorta.

[Auricular fibrillation. Antiarrhythmic treatment revisited]

Atrial fibrillation is one of the most common symptomatic sustained arrhythmias seen in clinical practice. Long-term control of heart rate and maintenance of sinus rhythm often require chronic antiarrhythmic therapy. For patients with disabling symptoms of atrial fibrillation that cannot be controlled with pharmacologic therapy, catheter ablation techniques of the atrioventricular junction and surgical procedures aimed at maintaining sinus rhythm have now been effectively used. The efficacy, risks and limitations of pharmacologic and non-pharmacologic therapies are presented in this review article.

[Pulse wave velocity as initial marker of atherosclerosis]

OBJECTIVE

To evaluate the influence of hypercholesterolaemia on arterial distensibility.

MATERIAL AND METHODS

43 male New Zealand White rabbits, with similar ages and weights, were included in the present study. The animals were divided in two groups: Group A (n = 15) was fed a normal diet; Group B (n = 28) was fed normal diet plus 0.1% cholesterol. at the beginning and after 6 and 9 months, blood samples were obtained for determination of serum cholesterol (total, esterified, LDL) and Triglyceride levels. Pulse wave velocity (PWV) was also evaluated, by mecanography, after 6 and 9 months of the beginning of the experiment. After 6 months (Group A = 4 and Group B = 7) and 9 months (Group A = 6 and Group B = 7) of the experiment, some animals were killed for anatomopathological studies.

RESULTS

Major differences were obtained between the two groups, specially in what concerns to LDL and cholesterol levels (p < 0.001). There was also a remarkable difference in PWV between the two groups (6.078 +/- 0.162/9.002 +/- 0.196 m/s at 6 months and 7.639 +/- 0.590/9.557 +/- 0.543 m/s at 9 months) from the rabbits fed normal or cholesterol diet, respectively. The anatomical lesions were only significant after 9 months. However there was a decrease in aorta internal diameters at thoracic and renal levels at 6 months (34% and 53%) and at 9 months (29% and 33%), without significant changes in their thickness. In the heart, the left ventricle (LV) had a significant thickness increase after 6 months (about 43%).

CONCLUSIONS

These data indicate that even before anatomical lesions had occurred, important functional changes are present, in the arterial wall. Then, the evaluation of the PWV could be a promising non-invasive diagnostic method of early atherosclerosis, with obvious implications concerning its prophylaxis and therapy.

[Hemodynamic effects of propafenone in dogs anesthesized with halothane or isoflurane]

OBJECTIVE

Several studies suggest that anaesthetic drugs influence the haemodynamic effects of the antiarrhythmic drugs. The aim of this study was to compare the haemodynamic effects of a standard dose of propafenone (1.5 mg/kg) on dogs anaesthetized with halothane or with isoflurane.

DESIGN

Randomized laboratory animal study.

MATERIAL AND METHODS

Six dogs were anaesthetized with 1% of halothane-Group I, and six dogs with an equianaesthetic dosage of isoflurane (1.5%)-Group II. Dogs breathed in spontaneous ventilation. Haemodynamic monitoring was performed with a femural arterial catheter and a flow-directed pulmonary artery catheter and cardiac output was measured by thermodilution. After a haemodynamic assessment considered as initial a bolus of 1.5 mg/kg of propafenone was given during a period of 30 seconds and similar assessments were made 5, 15, 30 and 60 minutes after.

RESULTS

Before propafenone, heart rate was significantly higher in Group II-isoflurane (p < 0.05). After propafenone we found: In both Groups, a decrease in the cardiac output (p < 0.05) with the mean arterial pressure maintained; in Group I (halothane) a decrease in the stroke volume (p < 0.05) which was not found in Group II (p = ns); In Group II (isoflurane) a decrease in heart rate (p < 0.05) not found in Group I (p = ns). All the changes were higher at the 5th minute values. 30th minute and 60th minute values were not significantly different from initial values.

CONCLUSION

In dogs anaesthetized with halothane 1.2 MAC a reduction in the stroke volume, resulting in a cardiac output decrease, was observed, suggesting that propafenone increases the negative inotropic action of halothane. In dogs anaesthetized with isoflurane 1.2 MAC the decrease in cardiac output was similar to the decrease in heart rate, and therefore no reduction in the stroke volume was observed. The decrease in the heart rate found in this group but not in the halothane group was probably related with the beta-blocker action of the propafenone. Looking to the systemic vascular resistances, our study suggested that propafenone didn't have any vasodilator effect during halogenated anaesthesia.

[Enalapril prevents myocardial remodeling in rats with arteriovenous fistula]

AIM OF THE STUDY

To evaluate the efficacy of enalapril in preventing cardiac myocyte remodelling in rats with arteriovenous fistulas.

EXPERIMENTAL DESIGN

We distributed thirty males Wistar rats in 3 groups: group A (control), group B (fistula) and group C (fistula + enalapril). An end to side fistula between the femoral artery and vein was produced in the right thighs of rats from groups B and C. Oral enalapril (0.07 mg/kg/day) was given to rats from group C. After 8 weeks the rats were sacrificed and their heart removed for pathologic study.

RESULTS

Body weight evolution was similar in all groups. Heart weight increased in group B (1.78 +/- 0.2 g) when compared to group A (1.55 +/- 0.11 g), (p < 0.02), and was similar (p = n.s.) in groups A and C (1.58 +/- 0.13 g). Heart weight/Body weight ratio was also increased in group B (4.4 +/- 0.55 mg/g) when compared to group A (3.6 +/- 0.5 mg/g), (p < 0.01), but was similar in groups A and C (3.66 +/- 0.4 mg/g) (p = n.s.). An increase in wall thickness was detected in group B in the right ventricle (p < 0.03), septum (p < 0.01) and left ventricle (p < 0.01) when compared to groups A and C. Myocytes cytoplasm volume fraction was increased in group B, when compared with group A, in all segments studied (right ventricle p = 0.011, septum p = 0.025, and left ventricle p = 0.031). Groups A and C were similar.

CONCLUSION

Enalapril prevents the structural remodelling of cardiac myocytes in this model of volume overload induced by an arteriovenous fistula.

[Isonitrile (sestamibi) as a valid alternative to thallium 201 for myocardial perfusion studies]

OBJECTIVE

SestaMIBI is a new technetium labeled radiopharmaceutical agent approved for myocardial perfusion studies. In the present work the authors analyzed the accuracy of this agent on the study of ischemic heart disease. CONCEPTION: The present paper was made considering the results of four previous studies around defined goals performed by the same research group.

SETTING

Cardiology and Nuclear Medicine departments in a general hospital.

RESULTS

Planar studies: global sensitivity for the diagnosis of ischemic heart disease was 100% and specificity of 67%. Tomocintigraphic studies and segmentary analysis of IHD: the accuracy for stenosis involving the left anterior descending artery was of 80%, 91% for the right coronary artery and 67.2% for left circumflex artery. Planar studies versus tomocintigraphy--SPECT (comparative study in the same population): global sensitivity of 86% for planar method and 97% for "SPECT". In patients with single vessel disease the results are also better with "SPECT" (75% vs 94%). In this series the presence of rest perfusion defects is frequent. In 75% was possible to correlate them with a significant lesion over the related coronary artery. The positive predictive value of this finding is of 92% for the lesions on the left coronary artery, 100% for left cincumflex and 59% for the right coronary artery.

CONCLUSIONS

1. The SestaMIBI is an excellent radiopharmaceutical agent for myocardial perfusion studies. 2. The accuracy of this agent for diagnosis of ischemic heart disease is quite good with a high sensitivity and specificity values. This conclusion is also valid for those patients with single vessel disease. 3. Scintigraphic studies performed with planar acquisition provide good quality images. Nevertheless tomoscintigraphy (SPECT) is more accurate namely in patients with single vessel disease. 4. In the present state of the art and regarding our results we can conclude that is too early for considering SestaMIBI like and agent for viability studies.

[Free thrombi in the left atrium. Report of a clinical case]

The authors describe a case of a floating thrombus in the left atrium, detected by a 2D echocardiography in a female patient suffering from dilated cardiomyopathy. At the follow-up, it was found that the mass was no longer detected inside the left atrium. This occurrence was not associated to any major embolic phenomena. A transesophageal echocardiographic study revealed the presence of a thrombus in the left atrial appendage.

[A follow-up by telephone of patients wearing a pacemaker--the experience of the Cardiac Pacing Center of the Hospitais de Universidade de Coimbra]

OBJECTIVE

To demonstrate the viability of the transtelephonic follow-up of paced patients, and its economical, human and practical consequences.

SETTING

Pacing center of a central university hospital and departments of cardiology in district hospitals.

INTERVENTIONS

400 patients under transtelephonic follow-up, between April 1983 and December 1992, with a total of 1200 transtelephonic consultations. Analysis of the parameters of the stimulation and of the ECG tracings transmitted by a Transmitter Receptor Medtronic Teletrace 9403.

RESULTS

No technical problems were found in the transtelephonic transmission and clear ECG tracings were recorded. A very substantial decrease in follow-up costs was so obtained.

CONCLUSION

The transtelephonic monitoring of paced patients is a possible, useful and accurate method of follow-up.

[Role of superoxide dismutase in the reduction of reperfusion injury of the ischemic myocardium. Lessons of the first experimental animal models]

Myocardial reperfusion is today the best alternative to save ischemic myocardium. However, reperfusion carries with him an aggressive potential that may mask its benefits. From a clinical point of view, it is necessary to create new complementary therapies to prevent such injury. One of such therapy in which a great deal of knowledge in experimental models has been accumulated is superoxide dismutase. In this work are presented some chemical, biological, and pharmacological characteristics of this enzyme. Several forms of reperfusion injury are discussed as well as the role of superoxide dismutase in their prevention. The experience gathered along the years is still small for prevention of cellular oedema, intramyocardial haemorrhage, and low/no-reflow. There is still some controversy about the role of superoxide dismutase in the reduction of myocardial necrosis. However, superoxide dismutase seems to be highly protective, as far as stunned myocardium and reperfusion arrhythmias are concerned.

[Pulse wave velocity as expression of arterial compliance and its importance in the evaluation of arterial hypertension]

STUDY OBJECTIVE

To determine the arterial compliance through the evaluation of pulse wave velocity.

DESIGN

Open study with direct comparison of different groups within a 12 week evaluation period.

PATIENTS

69 patients, 49 with hypertension and 20 normals individuals.

INTERVENTIONS

Different groups with the following treatments: Isradipine, Lisinopril, Dilevalol and no therapy.

MEASUREMENTS AND MAIN RESULTS

There is marked differences in the pulse wave velocity when hypertensive patients are compared with normal individuals (p < 0.001). In a 12 week therapeutic evaluation there is an improvement in the pulse wave velocity particularly when the arterial pressure was lowered to normal values in the hypertensive patients: Lisinopril (p < 0.005), Isradipine (p < 0.005), Dilevalol (p < 0.025).

CONCLUSIONS

It is very easy to evaluate the pulse wave velocity. Arterial compliance, which may be evaluated using the pulse wave velocity, is significantly reduced in hypertensive patients, compared with age-matched control subjects. The use of antihypertensive drugs is associated with changes in arterial compliance. There is a significant decrease in the pulse wave velocity after the administration of ACE inhibitors, calcium channel blockers and beta blockers for an equivalent fall in blood pressure. These observations emphasizes the potential importance of the changes in the large arteries, considered as either an associated factor or a consequence of elevated blood pressure, in the evaluation of the cardiovascular morbidity, and mortality of patients treated for hypertension.

[Relations between the levels of lipoprotein (a) and results of coronarography in patients with ischemic heart disease. Preliminary results]

The authors make a short revision about Lipoprotein(a) [Lp(a)], which has been referred as an independent risk factor for coronary disease. To confirm this results in a portuguese population, we studied serum Apo(a) [method IRMA.Kit Pharmacia.1 U/L Apo(a) = 1 mg/L Lp(a)], Apo A, Apo B, total cholesterol, HDL-cholesterol, triglycerides, calcium, uric acid, glucose, fibrinogen and ESR in 37 patients who were submitted to postmyocardial infarction coronarography (Judkins technic--Seldinger. Classic incidences. Significative lesions: greater than or equal to 75% in coronary vessels or greater than or equal to 50% in common main nk). The purpose was to search for changes on the plasmatic levels according to the results of the coronarography. The only change observed was in the Lp(a) levels, with important variations (p less than 0.05) between the defined groups: patients without significant coronary disease or disease on just one vessel [media (mean) = 30.1 mg/dl. Standard error (SE) = 7.9 mg/dl.n = 11] and another group of patients with coronary disease of two or three vessels [mean = 50.5 mg/dl.SE = 7.0 mg/dl.n = 26]; among the patients with two vessels disease were found significant changes (p less than 0.02) on Lp(a) levels according to the descending anterior coronary being [mean = 79.5 mg/dl.SE = 4.3 mg/dl.n = 8] or not [mean = 38.5 mg/dl.SE = 14.3 mg/dl.n = 7] implicated. These observations make the suggestion of Lp(a) as a risk factor for coronary disease, and a predictor for the gravity of the coronary disease in myocardial infarction.

[Assessment of the left ventricular function in patients with pacemakers VVI and DDD, using non-invasive methods (systolic time)]

OBJECTIVE

Determination of left ventricular function, in patients with ventricular inhibited (VVI) and atrioventricular universal (DDD) pacemakers, by measurement of systolic time intervals.

DESIGN

Twenty six patients were studied (six with DDD pacemakers and twenty with VVI pacemakers). In all of them systolic time intervals measurements were obtained the day before and one week after the implant.

PATIENTS

We have studied twenty six patients consecutively, and all of them completed the study.

INTERVENTIONS

The measurement of systolic time intervals was obtained, by the simultaneous recording of ECG, phonocardiogram and carotid arterial pulse. The recordings were obtained at a paper speed of 100 mm/sec.

MEASUREMENTS AND RESULTS

The values obtained before the implantation were similar in both groups, but one week after implantation they show a closer to normal ventricular function, in patients with DDD pacemakers.

CONCLUSIONS

The measurements of systolic time intervals, is a very easy method, to determine left ventricular function non invasively. In patients with DDD pacemakers, the left ventricular function, was better than in patients with VVI pacemakers.

[Non-invasive evaluation of left ventricular function (systolic time interval) in patients using double-chamber pacemakers programmed on DDD and VVI]

OBJECTIVE

To evaluate changes on left ventricular function as assessed by systolic time intervals (STI), by programming "physiological" pacemakers either on VVI or DDD mode.

STUDY DESIGN

Comparison of STI values--electromechanical systole (QS2); left ventricular ejection time (LVET); pre-ejection period (PEP); PEP/LVET--in patients submitted to double chamber pacing programmed in DDD or VVI mode.

SETTING

Cardiac Pacing Center in a Department of Cardiology at a University Hospital.

PATIENTS

We have studied 12 patients (3 men, 9 women), mean age 56.16 years (range 25-76 years) treated with double chamber pacing.

INTERVENTIONS

Initial measurements of STI in DDD or one week in VVI mode, and again after one week in DDD mode.

RESULTS

Significant changes were found after the first week in VVI pacing, versus baseline determination in DDD pacing, for LVET, PEP, and PEP/LVET (p less than 0.05). At the end of the second week (DDD pacing), there were also statistically significant differences for QS2 (P less than 0.05), LVET (P less than 0.01) and PEP/LVET (P less than 0.05) values when compared with the ones obtained in VVI pacing, at the end of the preceding week. No significant changes were found between the initial and the final STI determinations (both in DDD pacing).

CONCLUSION

We concluded for a better performance of the left ventricle at rest when "physiological" pacing is compared with VVI pacing.